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Inspired by the significant catalytic charring effect of metal–organic frameworks (MOFs), Cu‐MOF decorated ammonium polyphosphate (APP@Cu‐MOF) was prepared by coupling agents to improve the fire safety of epoxy resin (EP). After adding 9 wt% APP@Cu‐MOF, the fire performance of EP is significantly improved with limiting oxide index (LOI) value of 29.4 and UL‐94 V‐0 rating. The peak heat release rate (PHRR), total smoke production (TSP), CO production, and CO2 production of EP composite samples decreased by 34.6%, 54.7%, 24.6% and 30.0%, respectively. It is proposed that the synergistic effect among Cu‐MOF and APP promoted the char formation of EP. The dense carbon layers formed a barrier that prevented the transfer of heat and inhibited the release of toxic gases, thus acting as a flame retardant. This work provides a new strategy to develop a high‐efficient MOF‐decorated flame retardant with smoke inhibition, toxicity reduction, and catalytic carbonization effect. [ABSTRACT FROM AUTHOR]

The escalating threat of bacterial infections to human health necessitates innovative antibacterial strategies and materials. Despite this need, there is still a significant demand for materials that combine high mechanical and thermal properties with biocompatibility. To address these urgent issues, our study investigates the development of poly(vinyl alcohol) (PVA) composite with graphene flakes (GF) as fillers. The aim is to strengthen the unique properties of graphene to enhance antibacterial activity. Graphene oxide (GO) was used as a surfactant to achieve stable graphene dispersion in water, preserving its inherent properties while avoiding the drawbacks associated with common surfactants, such as property reduction and complex removal processes. In this study, the mechanical and thermal properties of PVA composites containing GO and GF are superior to those of pristine PVA. Especially, the PVA‐2 composite exhibited a notable enhancement in both tensile strength and elongation at break compared with the PVA composite, with increases of 7.8% and 15% respectively. Moreover, PVA‐2, 4, and 6 composites exhibit significant antibacterial efficacy, achieving 4.8 and 4.9 log CFU/cm2 for Staphylococcus aureus and Escherichia coli, respectively. These results indicate that the enhanced oxidative stress induced by GO as a surfactant, combined with the physical damage caused by the increased GF nanostructures. This study highlights the potential of PVA/GF/GO composites in biomedical and tissue engineering applications, providing a promising pathway for the development of new antibacterial materials. [ABSTRACT FROM AUTHOR]

Currently, flexible thermal interface materials (TIMs) containing hexagonal boron nitride (h‐BN) as thermal conductive fillers become a research hot spot. In this study, PDMS@BN composite films were prepared using spin‐coating technology, providing a facile and efficient method for the preparation of TIMs. The effects of spin‐coating speed and time on the thermal conductivity and the orientation degree of BN within composite films were investigated. Additionally, a theoretical model was established to calculate the thickness and thermal conductivity of PDMS@BN composite films under various spin‐coating conditions. The findings indicate that with an increase of spin‐coating speed and extension of spin‐coating time, the thickness of the composite films gradually decreases, while the in‐plane and through‐plane thermal conductivity gradually increases. When compared to a low spin‐coating speed of 500 rpm, the thermal conductivity of the films produced by a higher speed of 2500 rpm, exhibited an increase of 274%. The film achieves outstanding thermal conductivity (5.79 W m−1 K−1), extremely thin thickness (60 μm), high volume resistivity (1.22 × 1013 Ω cm) and excellent flexibility by incorporating 60 wt % h‐BN flakes. Overall, this study presents an efficiently and eco‐friendly approach for high‐performance TIMs. [ABSTRACT FROM AUTHOR]

This work uses pure polyvinyl chloride (PVC) with magnesium oxide (MgO) nanoparticles to enhance PVC's optical and shielding properties. The distribution of MgO nanoparticles in the PVC polymer was shown using a scanning electronic microscope, x‐ray diffraction, and Fourier transform infrared. The prepared samples' optical parameters and thermal analysis are investigated using ultraviolet (UV) spectroscopy and thermogravimetric analysis, respectively. The shielding characteristics parameters for the prepared samples were experimentally tested using a Cs‐137 point source with an energy of 0.662 MeV, and the outcomes were contrasted with what the XCOM software had calculated. Results indicated that optical constants were significantly affected by the addition of MgO wt% concentration. The linear attenuation coefficient was directly proportional to the weight concentration of MgO nanoparticle filler in the PVC matrix, and the ability to absorb UV increased. Adding MgO nanoparticle concentrations improved the PVC composite's radiation shielding behavior. It concluded that the PVC/MgO nanoparticle‐prepared samples are suitable for packaging for industrial applications and apron shielding for medical applications. [ABSTRACT FROM AUTHOR]

A range of new fluorine‐containing copolyarylates were successfully produced through interfacial polymerization using hexafluorobisphenol A (BPAF) featuring a symmetric trifluoromethyl group structure, bisphenol B (BPB), and two acyl chloride monomers as raw materials. The results indicated that the synthesized amorphous copolyarylates exhibited good solubility, with number average molecular weights (Mn) of 19,000–44,000 g/mol, weight average molecular weights (Mw) of 66,000–159,000 g/mol, and intrinsic viscosities of 0.66–1.19 dL/g. The thermal stability of copolyarylates increased with the increase of BPAF monomer content (0~100%), which was manifested by the linear increase of glass transition temperature (Tg) from 201.6 to 237.1°C, and the increase of 5% thermogravimetric weight loss temperature (T5%) from 474.1 to 491.5°C. The tensile strength of copolyarylates ranged from 52.63 to 59.93 MPa, the tensile modulus ranged from 1102.08 to 1502.84 MPa, and the elongation at break ranged from 32.0 to 75.5%. In addition, the copolyarylates had good dielectric properties with a dielectric constant of 2.58–3.75 at 107 Hz and a dielectric loss tangent of 0.021–0.028. [ABSTRACT FROM AUTHOR]

Highlights The bonding interface of carbon‐fiber‐reinforced polymer (CFRP)‐reinforced steel structure is a weak part, and nanomaterial‐modified adhesives are expected to improve its comprehensive performance. This paper investigates the micro‐modification mechanisms of nanomaterials on epoxy resin adhesives using molecular dynamics simulation method. It explores how the functionalized nano SiO2 and carbon nanotubes affects the thermal and mechanical properties of the epoxy resin adhesive. The models established using Materials Studio software include the pure epoxy resin adhesive model (EP) with varying degrees of crosslinking, the functionalized nano‐SiO2‐modified epoxy resin adhesive model (EP + SiO2/OH), the single‐walled carbon nanotube‐modified epoxy resin adhesive model (EP + SWNT), and the synergistic enhancements model of the epoxy resin adhesive with nano‐SiO2 and carbon nanotubes (EP + SWNT + SiO2/OH). Based on the aforementioned models, the Forcite module is used to calculate the free volume, glass transition temperature and mechanical properties of the adhesive. The results show that the degree of crosslinking effects significantly the mechanical performance of epoxy resin adhesive. A high degree of crosslinking restricts the movement of the molecular chain, enhancing the strength of the epoxy resin adhesive. Furthermore, the trend of the mechanical and thermal properties of the four models remains constant with the rise of temperature, and the properties decrease most significantly in the range of the glass transition temperature. Moreover, the epoxy resin adhesive doped with nanomaterials exhibits varying degrees of enhancement in mechanical and thermal properties. The epoxy resin adhesive reinforced with functionalized nano‐SiO2 and carbon nanotubes exhibits better properties compared to those with a single nanomaterial. The micro‐modification mechanism is revealed for nanomaterial modified epoxy resin adhesive. The degree of crosslinking effects significantly the mechanical performance of epoxy resin adhesive. The epoxy resin adhesive doped with nanomaterials exhibits varying degrees of enhancement in mechanical and thermal properties. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO) was prepared from waste plastic using the two steps pyrolysis method and subsequently functionalized with ethylene diamine (EDA) to develop amino‐functionalized rGO (EDA‐rGO). To make the thermal and mechanical properties more proficient, EDA‐rGO was further incorporated as a nanofiller into a low‐density polyethylene (LDPE) matrix using the melt mixing method followed by hot‐pressing. A variety of analytical methods, such as FT‐IR, XRD, XPS, DSC, TGA, DMA, Raman spectroscopy, and HRTEM, were used to characterize the elements and morphology of rGO and EDA‐rGO. The results showed that the addition of 5 wt% EDA‐rGO to LDPE polymers significantly improved the mechanical and thermal properties, such as storage modulus by 62%, loss modulus by 67%, young's modulus by 123%, tensile strength by 79.83%, respectively. The thermal decomposition temperatures of 5%, 10% and 50% were increased by 14.01, 9.34, and 4.8°C, respectively. This study provides a feasible and ecologically sustainable way of repurposing plastic waste concurrently enhancing the properties of polymer composites. Highlights: Synthesis & functionalization of rGO from waste plastic using EDA.EDA‐rGO used as a nanofiller to fabricate LDPE polymer nanocomposites.EDA‐rGO enhanced the thermal stability of LDPE nanocomposites.The tensile strength & modulus of the LDPE composites are greatly improved.The storage, loss modulus, Tm and Tc enhanced by 62%, 67%, 4.4°C & 2.6°C. [ABSTRACT FROM AUTHOR]

The continuous updating and iteration of electronic devices brings about a significant accumulation of heat. It is urgent to enhance the thermal properties of polymer‐based composites to alleviate the heat dissipation problem in the microelectronics industry. In this paper, the hot drawing process was introduced to increase the crystallinity of ultra‐high molecular weight polyethylene (UHMWPE) fiber and improve its thermal conductivity. The ultra‐high molecular weight polyethylene fiber/epoxy resin (UHMWPE fiber/Epoxy) composites with high thermal conductivity were prepared by compositing UHMWPE fiber with epoxy resin under vacuum conditions. Due to the good crystallinity of the UHMWPE fiber (86%), an efficient thermal conduction path is provided for phonons in the axial direction along the fibers. The results show that the thermal conductivity of the composites reaches a maximum of 3.51 W/mK (in‐plane), which is 17.47 times higher than that of the epoxy resin (0.19 W/mK). The thermography pictures indicate that the composites have better heat transfer capacity with an increase in the draw ratio (λ). In addition, the composites also have the characteristics of low density and low electrical conductivity. These researches will provide a new idea for the preparation of all‐polymer composites with high thermal properties. Highlights: A hot drawing process was introduced to increase the crystallinity of UHMWPE fiber for improving thermal conductivity.High crystallinity facilitates the reduction of phonon scattering and the transmission of thermal energy by phonons.The obtained polymer composites exhibit an ultra‐high in‐plane thermal conductivity. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced epoxy resin matrix composite is one of the most important composite materials in the world. Many researchers have conducted a lot of research on epoxy resin matrix systems in recent years, mainly to improve the problem with the short curing time of the matrix system and epoxy resin's high viscosity. The final aim is to enhance various aspects of composites' performance and optimize the production process. A new type of water dispersed epoxy resin matrix system is investigated in this paper and the target is to optimize the mechanical, thermal, and electrical performances of the composites with the water dispersed epoxy resin matrix by varying different doping particles and different resin/catalyst ratios. Through a series of experiments, it is evident that varying the ratio of resin to catalyst in the matrix system will not significantly improve the mechanical as well as thermal properties of the composites. However, increasing the amount of catalyst in the matrix system can greatly improve the electrical properties of its composite samples. In addition to this, the addition of doping particles to the matrix systems has the effect of slightly enhancing the tensile modulus, thermal conductivity, and electrical conductivity of their composites. Highlights: A new water‐dispersed epoxy resin matrix system improves processing technology.Increasing amount of catalyst in the matrix system improves electrical resistivity.Adding particles to matrix systems has a slight effect on different properties. [ABSTRACT FROM AUTHOR]

Nylon nanocomposites were prepared by in‐situ ring‐opening polymerization to overcome the problem of poor properties due to the uneven dispersion of the nanoparticles by the traditional melt blending. This high‐performance polyamide 6 (PA6) nanocomposites with high dispersion and strong interface was prepared by grafting PA6 onto the surface of cellulose nanocrystals (CNC). The micromorphology, mechanical, crystalline and thermal properties of the composites were also investigated. Firstly, the hydroxyl group on the surface of CNC reacted with the para isocyanate of toluene diisocyanate (TDI), and the remaining ortho isocyanate was blocked by caprolactam to prepare CNC grafted with caprolactam (CNC‐g‐CL). Then CNC‐g‐CL was used as an activator to prepare cellulose nanocrystal grafted with polyamide 6 (CNC‐g‐PA6) composites by the ring‐opening polymerization of caprolactam on the CNC. The effects of different reaction temperatures, solvent amounts and molar ratios on the grafting rate of CNC‐g‐CL were investigated. The results showed that the highest grafting rate of CNC‐g‐CL with 66.7% was achieved at a reaction temperature of 45°C, 0.1 g/mL CNC in toluene, and a molar ratio of 6 for TDI/CNC. Further, different CNC‐g‐PA6 composites prepared from different CNC content and activator content were explored. For CNC‐g‐PA6 composites, CNC was uniformly dispersed in the PA6 matrix and had a good compatibility with the matrix. CNC exhibited significant reinforcement in the composites with a tensile strength of up to 108 MPa. In addition, the glass transition temperature of CNC‐g‐PA6 was increased to 92°C, which significantly improved the heat resistance of the new composites. Highlights: Effects of reaction condition of CNC and TDI on DSTDI and DSCL were studied.Effects of CNC and activator content on CNC‐g‐PA6 properties were studied.CNC is uniformly dispersed in PA6 with average particle size less than 1 micron.The nylon matrix was significantly strengthened by the addition of CNC.The addition of CNC significantly improved the heat resistance of the composites. [ABSTRACT FROM AUTHOR]

The development of innovative composite materials through the amalgamation of thermoplastic polyurethane (TPU) with bismuth sodium titanate (BNT) and carbon nanotube (CNT) fillers was investigated. Before the composite fabrication, the fillers' surfaces were treated to enhance their compatibility with the TPU matrix. Hybrid fillers of BNT and CNTs were fabricated by mixing the two types of filler particles through ball milling and subsequently annealing the mixture at 250°C. Melt‐blending and injection molding were utilized to synthesize the composites at 210°C processing temperature. The prepared composites showed significantly enhanced thermal conductivity, dielectric constant, thermal stability, and thermomechanical properties compared with the neat TPU matrix. For instance, the dielectric constant was enhanced by 340% upon the inclusion of 40 wt.% BNT and CNT fillers compared to the neat TPU matrix (40CBNT‐TPU has 13.2). In particular, the inclusion of BNT‐CNT particles in the TPU matrix improved the thermal conductivity of the TPU matrix by 1180% tremendously as compared to neat TPU (40CBNT‐TPU has 2.6 W/(m.K)). Highlights: Crystalline bismuth sodium titanate (BNT) is fabricated.Degradation of 8 wt.% of the IPDI‐treated BNT proves surface treatment.Dielectric constant (DC) improved by 340% compared to neat TPU.Thermal conductivity (TC) enhanced 11.4 times compared to neat TPU.Improvement in TC and DC will make it applicable in electronic materials. [ABSTRACT FROM AUTHOR]

The matrix cracking of carbon fiber reinforced epoxy resin based composites (CFRPs) at cryogenics (such as liquid nitrogen temperature) is a major issue affecting the normal operation of deep space and deep‐sea detectors, as microcracks caused by the thermal residual stress of both can reduce the structural integrity of the devices. In this work, we report an epoxy (EP) nanofiller CuO nanorods (CuO NRs) with negative thermal expansion properties at cryogenics. Experiments showed that CuO NRs can effectively inhibit the shrinkage of EP at cryogenics and improve the mechanical properties of EP at cryogenics. A temperature dependent prediction model for the tensile strength of EP/CuO NRs was proposed, and the predicted results were in good agreement with experimental results. Finally, through a combination of experiments and theory, it was demonstrated that the tensile strength of EP/CuO NRs at cryogenics is jointly enhanced by the enhancement effect of the nanomaterials and the axial compressive thermal residual stress between EP and CuO NRs. Highlights: Successfully prepared CuO nanorods with negative expansion properties at low temperatures, and found that they can effectively inhibit the shrinkage of epoxy resin at cryogenics.At cryogenics, the expansion of CuO nanorods enhances their interface effect with epoxy resin and improves the tensile strength of epoxy resin composites.The theory of tensile strength of epoxy resin at cryogenics was proposed for the first time. Theoretical analysis shows that the low temperature residual thermal stress between CuO nanorods and epoxy resin is the main factor to improve its tensile strength. [ABSTRACT FROM AUTHOR]

Poor interfacial adhesion between carbon fibers (CF) and the resin matrix has been a limiting factor in advancing the properties of composites. To address this challenge, this study employs the sizing method to coat carbon nanotubes (CNTs) and hexagonal boron nitride nanosheets (h‐BN) onto the CF surface. The 3D structures formed by strategic of combination 1D and 2D nanomaterials, markedly enhances the mechanical, thermal and frictional properties of CF composites. The results reveal a significant boost in the flexural strength, flexural modulus, interlaminar shear strength and interfacial shear strength of the prepared CF composites, registering increases of 53.96%, 60.41%, 55.58% and 55.35%, respectively. These advancements stem from the heightened surface reactivity and roughness of the fibers, facilitated by the synergistic interactions between CNTs and BN. Furthermore, the thermal conductivity of the composites exhibits a remarkable increase of 63.56%, attributed to the synergistic coupling between CF and BN, establishing an efficient thermal conductivity pathway within the composites. This research provides a highly effective approach for crafting high‐performance CF composites. Highlights: Construction of 3D network structures on CF surfaces by the sizing method.Synergistic coupling between BN and CNT enhances composite properties.Synergistic enhancement of friction and thermal properties of CF composites. [ABSTRACT FROM AUTHOR]

The high‐performance PPS/PEEK blends/composites were prepared with different mass ratios using polyphenylene sulphide (Solvey, Ryton®‐R‐4‐230 NA) and polyetherether ketone (Victrex, PEEK450 GL 30). All the blend samples had a single Tg, which revealed good compatibility between PPS and PEEK. The Tm was increased from 279.6 to 339.9°C due to addition of PEEK into PPS. Also, addition of PEEK into the blend increased the impact and tensile strength of the PPS material. The impact strength of the blend, PPS/PEEK (20/80) exhibited the maximum value of 113.64 J/m which was higher than that of PPS (70.66 J/m). The tensile strength of the blend was increased continuously with increasing the content of PEEK from 20 to 80 wt. % and reached the maximum value of 160.64 MPa. Additionally, milled carbon fiber (MCF) was also incorporated in order to obtain high strength PPS/PEEK blends/composites with good dielectric property. The dielectric performance of the composites was observed to increase with MCF content (in the frequency range 5.8 to 18 GHz). Highlights: This investigation relates to high‐performance PPS/PEEK blends and composites.Incorporation of milled carbon fiber resulted promising dielectric properties.Such composites may have Advanced structural EMI shielding electronics and/or aerospace applications. [ABSTRACT FROM AUTHOR]

Three‐dimensional molybdenum disulfide (MoS2) functionalized MWCNTs hybrid nanoparticles were synthesized using in‐situ hydrothermal reaction. Two types of hybrids, MoS2/MWCNTs‐1 and MoS2/MWCNTs‐2 with MWCNTs to MoS2 precursor weight ratios 1:2 and 1:1 respectively were prepared with varying degrees of hybridization and the effects of their incorporation on tensile strength and fracture toughness properties of epoxies were investigated. Epoxy/MoS2/MWCNTs‐2 nanocomposites showed exceptional mechanical properties due to their improved dispersion, constrained chain mobility and excellent interfacial interactions. MoS2/MWCNTs‐2 nanocomposites showed maximum improvement of tensile strength by 28.52% at 0.5 wt% nanofiller concentration and the highest improvements in fracture toughness by 172% at 0.2 wt% nanofiller concentration. The excellent enhancement of fracture toughness properties was due to the synergic effect of MoS2/MWCNTs hybrid nanoparticles due to the crack pinning and bifurcation properties of MoS2 nanoparticles along with the pull‐out and crack bridging mechanisms of MWCNTs as observed in morphological analysis of fractures nanocomposites. The incorporation of 0.2 wt% of MoS2/MWCNTs‐2 increased the degradation temperatures of epoxy from 591 to 796°C at 95% weight loss due to the improved physical barrier effect. Highlights: MoS2/MWCNTs nanoparticles were synthesized using in‐situ hydrothermal reaction0.5 wt% MoS2/MWCNTs‐2 incorporated epoxies showed highest tensile strength0.2 wt% MoS2/MWCNTs‐2 incorporated epoxy composites show improved K1c valueIncorporation of MoS2/MWCNTs improved the thermal stability of epoxySynergistic effect of nanocomposite due to crack pinning, bifurcation & bridging [ABSTRACT FROM AUTHOR]

Fluorine rubber (FKM) stands as a pivotal sealing material extensively employed in aerospace and nuclear industries. However, its efficacy will be seriously affected by ionizing radiation. Enhancing its radiation resistance becomes imperative to uphold the stability and safety of associated equipment. This study introduced hexagonal boron nitride (h‐BN) into the FKM as radioprotective fillers through mechanical blending. The interfacial interaction between matrix and h‐BN, the mechanical performances, thermal properties, and radiation stability of composites were systematically examined. Noteworthy findings highlight the presence of robust interaction forces between h‐BN and the matrix, leading to increased crosslink density and improved mechanical properties. The tensile strength of composite with 10 phr fillers (BN/FKM‐10) increased by 30% compared to that of pure FKM. Simultaneously, the introduction of h‐BN greatly enhanced thermal conductivity and radiation stability. The absorbed dose required to achieve a 50% reduction in elongation at break of BN/FKM‐10 surpassed that of FKM by 1.69 times. These results underscore the potential of incorporating h‐BN to simultaneously enhance the mechanical performance, thermal property, and radiation resistance of fluorine rubber. Highlights: The chemical interaction force between h‐BN and FKM was confirmed.FKM composites tensile strength was enhanced by h‐BN as an additive crosslinker.The incorporation of h‐BN improves FKM composites thermal conductivity.The radiation resistance of FKM composites has been improved with h‐BN. [ABSTRACT FROM AUTHOR]

Organic–inorganic composites have attracted great interest, due to their remarkable impact, causing improvements in the mechanical properties of polymers when compared with their pure forms. Hence, this study has been attempted to investigate and compare the various properties of high‐density polyethylene (HDPE), separately doped with two different types of clay minerals using melt‐mixing and compression‐molding techniques. The fourier transform infrared spectroscopy (FT‐IR), x‐ray diffraction (XRD), and scanning electron microscope (SEM) were used to characterize the structural and morphological properties of the resulting composites, while, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were employed to characterize their thermal properties. Morphological investigations indicated homogeneous dispersion of both clay materials in the HDPE matrix. Moreover, an investigation was conducted on the mechanical properties of composites, including elastic modulus, yield stress, tensile strain at break, tensile strain at yield, tensile stress at break, and ultimate tensile strength. According to the mechanical data, adding 6.0 wt% of bentonite or dolomite to HDPE led to an increase in the elastic modulus up to 125% and 116% increments, respectively. An increase in the filler content in the composite from 2.0 to 8.0 wt% resulted in a slight decrease in tensile stress at break, yield stress, tensile strain at break, and tensile strain at yield. [ABSTRACT FROM AUTHOR]

Laminated polymer composites are widely used in ballistic barriers where polyethylene can be applied. The mechanical properties of polymers can be improved with the addition of nanofillers. Therefore, this work evaluates the effect of the combination of montmorillonite Cloisite 30B (OMt) and graphene (Gr) on the dynamics compression properties obtained from a split‐Hopkinson pressure bar (SHPB) test for nanostructured maleinized high‐density polyethylene (HDPE). The nanofillers are incorporated into the polymeric matrix in its molten state, and their dispersion is evaluated through x‐ray diffraction and transmission electron microscopy analyses. Thermal analysis, including differential scanning calorimetry and thermogravimetric analysis are performed. Additionally, the viscoelastic behavior of the materials is studied from the results of storage and loss modulus obtained by dynamic‐mechanical analysis. Under the SHPB test conditions, it is possible to evaluate the material stress–strain curve, identifying its yield point, compressive strength, and deformations to calculate the elastic stiffness and toughness of the material. The nanocomposite with 3% OMt and 0.75% Gr (wt.%) shows the highest average compressive strength and toughness values. Furthermore, this sample shows similar Tpeak temperature, improved crystallinity index, storage, and loss modulus, with similar glass transition temperature compared to the HDPE sample. [ABSTRACT FROM AUTHOR]

Understanding how dangling fragments of polyurethanes (PU) affect its microphase separation structure and damping properties can provide insights for designing desired materials at the molecular scale. By varying the types of diol extenders (such as 1,2‐ethyleneglycol, 1,2‐propanediol, and 1,2‐butanediol), PU samples with different dangling residues were successfully synthesized. Using atomic force microscopy and small‐angle x‐ray scattering, we confirmed that the introduction of dangling chains disrupts microphase separation and demonstrated a correlation between the degree of suppressed microphase separation and the size of the dangling residues. Fourier transform infrared spectroscopy and molecular dynamics simulations confirmed that dangling chains reduce the hydrogen bonding index while increasing the phase compatibility between soft and hard segments. Differential scanning calorimetry (DSC) measurements revealed an increased glass transition temperature (Tg), indicating hindered movement of backbone segments due to dangling chains. Moreover, lengthening the dangling chains further decreased Tg. Dynamic mechanical analysis (DMA) demonstrated improved damping properties with the introduction of dangling chains, although increasing chain length led to deteriorating damping properties, consistent with observations from DSC. These findings suggest that the variations in macroscopic properties of PU induced by dangling chains are linked to hydrogen bonding interactions and micromorphology at the molecular level. [ABSTRACT FROM AUTHOR]

In this work, a novel approach is taken to enhance the thermal conductivity and mechanical properties of composites by developing highly efficient thermally conductive PVDF‐based composites. This is developed by incorporating tetra‐pod zinc oxide whiskers (T‐ZnOw) in conjunction with multiwalled carbon nanotubes (MWCNT) to form binary hybrid fillers within a polyvinylidene fluoride (PVDF) matrix. Polydopamine (PDA), characterized by physical adsorption, is selected for surface coating on T‐ZnOw since T‐ZnOw is easy to self‐agglomerate and difficult to modify by physical and chemical methods. The coating aims to improve the dispersibility of T‐ZnOw and reduce the interfacial thermal resistance with the substrate. MWCNT is oxidized to improve its dispersion ability while strengthening the interaction with the matrix, due to the absence of interaction between MWCNTs and polymer matrix and poor dispersibility with the matrix. The dispersity of PDA@T‐ZnOw and o‐MWCNT is improved, and the three‐dimensional hybrid network structure can be better constructed to improve the thermal conductivity of the composite membrane. At a filler content of 25 wt%, the thermal conductivity reaches 0.302 W m−1 K−1 for T‐ZnOw–MWCNT–PVDF and 0.222 W m−1 K−1 for PDA@T‐ZnOw–o‐MWCNT–PVDF. [ABSTRACT FROM AUTHOR]

Highlights Increasing miniaturization and integration of microelectronic devices have led to an unprecedented attention on heat dissipation and signal transmission of electronic equipment. However, the mostly used method to enhance the thermal conductivity of polymers by adding thermally conductive fillers usually results in the increase of dielectric constant (Dk). It was still challenging to synergistically achieve low Dk and high thermal conductivity of polymer‐matrix composites. Herein, hydroxylated boron nitride nanosheet (BNNS‐OH) with a high yield of 35.67% was prepared by the liquid ultrasonic exfoliation under the assistance of sodium cholate (SC), and grafted with (1H,1H,2H,2H‐perfluorodecyl) trimethoxy silane to prepare fluorinated boron nitride nanosheets (F‐BNNS), which can uniformly disperse in liquid silicone rubber (LSR) and reduce the Dk of LSR composites. The thermal conductivity of LSR composites with 20 wt% F‐BNNS reached 0.489 W·m−1·K−1, showing an increase of 307.35% in comparison with pure LSR (0.12 W·m−1·K−1). Meantime, the Dk of as‐obtained LSR/F‐BNNS (20 wt%) composites is reduced from 3.4 to 2.6, and the dielectric loss (Df) is less than 0.012. The facile and rational design of fluorinated BNNS offers a new insight for the high‐end electronic packaging materials. A new method of exfoliation and fluorinated treatment of h‐BN was proposed. The LSR composites achieved an ultralow Dk of 2.63 via fluorinated BNNS. Thermal conductivity of LSR composites increased by 307.35% than pure LSR. [ABSTRACT FROM AUTHOR]

Highlights Thermal expansion of materials is a critical factor influencing their dimensional stability. This study explores the regulation of thermal expansion in composite materials through the incorporation of carbon fibers and zirconium tungstate particles. The influence of fiber length on the thermal expansion behavior of these composites was investigated. The investigation reveal that the variation in the relative elongation ratio (dl/L0) of the carbon fiber‐reinforced zirconium tungstate composites is nonlinear, characterized by an initial increase, subsequent decrease, and a final resurgence. Notably, an increase in fiber length results in a mitigated rate of increase in the (dl/L0) ratio. Furthermore, composites fabricated with shorter fibers exhibit a higher coefficient of thermal expansion (CTE). Upon elevating the temperature to 250°C, the CTE for composites reinforced with 100 and 500 mesh carbon fibers escalate to 24.5 × 10−6/K and 74.6 × 10−6/K, respectively. These values represent an 8% and 116% enhancement relative to those measured at 50°C. The thermal expansion properties are improved by adding carbon fiber and ZrW2O8 nanoparticles. Utilizing fiber lengths ranging from 100 to 500 mesh effectively diminishes the CTE. The Cf‐ZrW2O8/9621 composite exhibits non‐linear behavior in its dl/L0 ratio. Within the range, longer fibers are more beneficial for reducing the CTE. [ABSTRACT FROM AUTHOR]

In order to suppress the damage of cable insulation caused by water tree structure formed by micro‐droplets at insulation defects in low density polyethylene (LDPE) materials under AC electric field. In this paper, the siloxane group is grafted onto LDPE by melt grafting method, and different content of comonomer styrene (St) is added to improve the grafting rate of siloxane group grafted polyethylene. The effect of St on the microscopic characteristics of LDPE grafted KH570 is studied. In order to verify the accuracy and timeliness of water tree self‐healing of grafted polymer insulation materials, the microstructure characteristics of LDPE ungrafted and grafted polymer samples are analyzed by Fourier transform infrared spectroscopy, gel content test, and differential scanning calorimeter. Second, the AC dielectric properties of LDPE ungrafted and grafted polymer samples are studied by AC breakdown experiment and space charge test. Finally, the water tree length, micropore defects, and self‐healing of the samples are observed by optical microscopy and polarization and depolarization current method, and the changes of chemical composition in the water tree area before and after aging are analyzed by infrared spectroscopy. The principle and mechanism of repairing water tree defects with grafted monomers are explained. This paper not only combines the previous research results of self‐healing materials, but also provides a new method for the preparation process of LDPE grafted polymer, which has a good research prospect in practical application. [ABSTRACT FROM AUTHOR]

Allyl ether naphthol resin (ANPF) was synthesized by introducing 1,5‐dihydroxynaphthalene and 2,7‐dihydroxynaphthalene into phenolic resin and was copolymerized with 4,4′‐bismaleimidodiphenylmethane resin (BDM) to obtain allyl ether naphthol‐modified bismaleimide resins (15‐ANPF‐BDM and 27‐ANPF‐BDM). The resulting thermal stability and glass transition temperature (Tg) were explored by thermogravimetric and dynamic mechanical analyses. The char yield of 15‐ANPF‐BDM at a temperature of 800°C was 46.0%. Additionally, the Tg of 15‐ANPF‐BDM was measured as 311°C, which is an increase of 44°C compared to that of c. The mechanical properties of the ANPF‐BDM/quartz fiber (Qf) composites were also investigated. The results reveal that ANPF‐BDM/Qf composites exhibit similar mechanical strength to APF‐BDM/Qf composites at room temperature. In addition, the mechanical properties of the ANPF‐BDM/ Qf composites demonstrated significant improvement in mechanical properties retained significantly improved at 200°C, with a 68% flexural strength retention and a 96% interlaminar shear retention of 15‐ANPF‐BDM/Qf composites. Thus, ANPF‐BDM/Qf composites exhibit outstanding mechanical properties at 200°C. [ABSTRACT FROM AUTHOR]

To improve the comprehensive properties of polybutylene furandicarboxylate (PBF), 2,5‐furandicarboxylic acid (2,5‐FDCA), and aliphatic chain diol 1,8‐octanediol and 1,4‐butanediol were used as monomers to synthesize a series of bio‐based polybutylene glycol‐octanediol 2,5‐furandicarboxylate (PBOF). The results showed that the chemical composition of PBOF could be controlled through the molar ratio of monomers. Compared with PBF, as the proportion of octanediol segments gradually increased, PBOF could gradually transform from semi‐crystalline thermoplastic to amorphous form, and the glass transition temperature (Tg) gradually decreased. The crystallization ability reduced but a part of the crystal area was still retained. The copolyesters still has a decomposition temperature above 370°C, indicating excellent thermal stability. The introduction of the octanediol segment significantly improved the tensile mechanical properties and flexibility of the POBF copolyester. These meet the requirements for the preparation of bio‐based engineering plastics. The water absorption rate of PBOF showed that it may have certain degradable potential. PBOF copolyesters have potential application prospects in bio‐based medical plastics and biodegradable packaging polymer materials after copolymerization modification. [ABSTRACT FROM AUTHOR]

This study aims to assess the effect of physical modification techniques on the properties of millet starch. The starch isolated from barnyard millet (Echinochloa frumentacea) is subjected to ultrasonication (20 kHz; 30 and 60 min) and gamma irradiation (5 and 10 kGy). The protein content decreases slightly (by 2.5–3.8%) with gamma irradiation and significantly (by 5.7–6.9%) with ultrasonication. As compared to the native starch (20.56%), the amylose content of ultrasonicated starch is significantly higher (21.42% and 21.88%), while it is significantly lower (19.73% and 19.18%) for gamma‐irradiated starch. The swelling power of the native starch (13.57%) increases significantly with ultrasonication (14.21% and 14.33%) treatment; while it decreases significantly with gamma irradiation (13.17% and 12.25%) treatment. The solubility increases to 11.23%, 11.19%, 12.09%, and 13.31% from 10.45%, with both modifications. The peak viscosity of modified starches decreases significantly (2872 and 2700 cP) as compared to the native starch (3832 cP). The starches exhibit a greater value for storage modulus (G′) as compared to loss modulus (G″), reflecting their elastic nature. These transformations in the microstructure, gelatinization, and physicochemical properties of native starch can further be explored for food and textile industrial applications. [ABSTRACT FROM AUTHOR]

Summary: The present study investigates the impact of germination (72 h) on physicochemical, protein solubility, in vitro protein digestibility, antinutrient, antioxidant, and structural properties of sorghum flour. Germination resulted in a reduction of crude protein, fat, fibre, and ash. However, it significantly improved the DPPH (58.42%–69.44%), total phenolic content (1.31–3.58 mg GAE g−1), and total flavonoid content (57.66–80.16 mg QE g−1). Germination also increased in vitro protein digestibility (50.12%–75.52%) and Fe2+ chelating activity (11.18%–48.06%), while reducing antinutrients such as phytic acid (176 to 86 mg/100 g) and tannin (3.53–2.16 mg/100 g). Structural analyses (XRD and FTIR) revealed modifications in crystalline and molecular structures, while scanning electron microscopy showed disrupted starch granules in germinated flour. These findings suggest that germination enhances the functional and nutritional properties of sorghum flour, making it more suitable for various applications in food products. [ABSTRACT FROM AUTHOR]

The susceptibility of either oxidation into Sn(IV) or disproportionation into Sn(IV) and Sn(0) limits the study of metal tin‐(II)‐borate ceramics. We report mullite‐type SnCrBO4 and SnVBO4 synthesized in sealed quartz tubes by conventional solid‐state method. X‐ray powder diffraction data Rietveld refinements confirm that both compounds are isostructural to PbMBO4 phases for M = Al, Ga, Cr, Mn, and Fe. The end‐members show a complete miscibility within the Sn(Cr1−xVx)BO4 solid solution. Both the microstructural (average crystallite size, microstrain, and degree of crystallinity) and crystal structural (metric parameters, bond lengths, polyhedral volume, and polyhedral distortion) parameters are observed with respect to the compositional x‐value. The stereochemical activity of the 5 s2 lone electron pairs of Sn2+ cations has been measured by using the Wang–Liebau eccentricity parameter. The structural features are complemented by 119Sn Mössbauer, Raman, and Fourier‐transformed infrared spectroscopy. The 119Sn Mössbauer isomer shifts and the quadrupole splitting values confirm the SnO4 coordination and an Sn(II) valence state. The electronic band gap has been calculated from the UV/Vis diffuse reflectance spectra, which slightly increases with successive decrease of the cationic radius from V to Cr. Temperature‐dependent inverse DC magnetic susceptibility suggests that SnCrBO4 and SnVBO4 are antiferromagnetic and ferromagnetic (FM) with a Néel temperature of 17.2(1) K and a Curie temperature of 29.8(1) K, respectively. Alike the end‐member SnVBO4, Sn(Cr0.5V0.5)BO4 is also found to be a rare FM insulator. The thermal stability decreases with increasing vanadium content in the solid solution. [ABSTRACT FROM AUTHOR]

Thermal and electrical properties were investigated for five nominally phase‐pure high entropy carbide ceramics. The compositions (Hf0.2Nb0.2Ta0.2Ti0.2Zr0.2)C, (Cr0.2Hf0.2Ta0.2Ti0.2Zr0.2)C, (Hf0.2Mo0.2Ta0.2Ti0.2Zr0.2)C, (Hf0.2Ta0.2Ti0.2W0.2Zr0.2)C, and (Hf0.2Mo0.2Ti0.2W0.2Zr0.2)C were synthesized by carbothermal reduction of oxides. The thermal diffusivity and heat capacity were measured from room temperature to 1800°C. The room temperature thermal conductivity ranged from 5.1 W/mK for (Hf0.2Mo0.2Ti0.2W0.2Zr0.2)C to 9.0 W/mK for (Cr0.2Hf0.2Ta0.2Ti0.2Zr0.2)C. The thermal conductivity increased over the temperature range with maximum conductivities of 19.6 W/mK measured for (Hf0.2Mo0.2Ta0.2Ti0.2Zr0.2)C to 29.7 W/mK for (Cr0.2Hf0.2Ta0.2Ti0.2Zr0.2)C at 1800°C. The electron contribution to thermal conductivity calculated from measured electrical resistivity varied from 41% to 52% of the total thermal conductivity. The tungsten and molybdenum containing compositions had higher phonon contributions while the niobium and chromium containing compositions had nearly equal electron and phonon contributions to thermal conductivity. [ABSTRACT FROM AUTHOR]

Filler components play a crucial role as thermo‐mechanical reinforcement to the epoxy‐based solder mask, ensuring effective insulation and passivation. This study investigates the impact of different inorganic filler types (talc, silica (SiO2), boron nitride (BN) and barium sulfate (BaSO4)) and loadings (5 and 15 wt%) on the tensile and thermal properties of the epoxy composites. The composites were blended, cast and thermally cured. Of these composites, only 15 wt% SiO2/epoxy composite exhibits notable increments in both tensile strength and modulus, surpassing unfilled epoxy by 11.65% and 31.9%, respectively. It also displays the highest elongation at break, supported by small particle size, high specific surface area and minimal void volume fraction. For thermal tests, the addition of all fillers increases the storage modulus in both glassy and rubbery regions, especially 15 wt% talc/epoxy composite with 30.09% increment at 25 °C. Additionally, all fillers raise the glass transition temperature (Tg), notably improving it by 9 °C in the 15 wt% BN/epoxy composite. Moreover, their inclusion generally enhances the onset decomposition temperature (Tonset) and reduces weight loss during decomposition. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The segment character of polyurethanes (PUs) determines the micromorphology and properties. The effective segment regulation can customize the favorable performance of PUs. Herein, silicon covalent‐modified polyurethanes (MPUs) were prepared by incorporating diphenylmethane diisocyanate (MDI) and diphenyl silanediol (DPSD) into PU molecules as hard segments via a two‐step method. Distinctive microphase separation structures from sheet morphology to radial sheet or withered flower‐like microdomain were formed by adjusting hydrogen bonding of hard segments and post‐treatment techniques. Thus, with the addition of DPSD in hard segments, the thermo‐optic responses for MPUs occurred due to the different microphase evolution under thermal effect. And with the further addition of DPSD, the effect of thermal stimuli on the transmittance gradually weakened. It was very clear that with increasing the temperature, the transmittance of MPUs showed a gradual increase owing to melting the microcrystals or destroying the ordered accumulation of hard segments. Meanwhile, the high mechanical properties were obtained, higher 15 times tensile strength and more than 100 times elastic modulus than those of pure PU as well as the excellent thermal stability. In sum, this study was of great significance for developing new functionalized PU materials. Highlights: Polyurethanes were prepared by inducing modified silicon functionality.The distinctive microphase separation evolution of MPUs was found.Thermal stimuli responses showed a gradual decrease due to different structure.High mechanical properties and thermal stability were also obtained. [ABSTRACT FROM AUTHOR]

Bismaleimide (BMI) resins is widely used in the aerospace field because of its excellent properties, but its poor toughness limits the possibility of its application in a wider range of fields. Therefore, a novel bio‐compound, 4‐(allyloxy)‐3‐methoxy‐N‐(3‐(triethoxysilyl)propyl)benzamide (AMTPM), was designed and synthesized from renewable vanillin, which has Schiff‐base structure, silico‐oxygen bond structure, and allyl structure. The chemical structure of AMTPM has been characterized and validated by Fourier transform infrared (FTIR) and hydrogen nuclear magnetic resonance (1H NMR). It was found that the addition of AMTPM can effectively promote the curing behavior of BD resins (BMI and diallyl bisphenol A (DBA) was mixed and cured at the ratio of 1:0.87, named BD resins). AMTPM can affect the thermal stability and improve the mechanical properties of BD‐AMTPM resins (BD resins modified by AMTPM in different addition), and the detailed discussion was conducted. With the increase of AMTPM content, the thermal stability of BD‐AMTPM resins was deteriorated while the residual weight percentage at 800°C (Yc) was increased. When the content of AMTPM reached 12 wt%, the results showed that Yc achieved the values at a magnitude of 37.57%. Meanwhile, the glass transition temperature (Tg) achieved 320°C. Among the BD‐AMTPM resins system, the BD‐6 wt% AMTPM has the best toughness and mechanical properties. The impact strength was increased by 29.2%, the tensile strength was increased by 22.1% and the elongation at break was increased by 44%. The fracture morphology of BD‐AMTPM resins was also studied by scanning electron microscopy (SEM) to support the mechanical experimental conclusions. This study provides a more environmentally friendly and convenient modifier, which is of great significance for expanding the application of bismaleimide resin. Highlights: A bio‐based modifying agent (AMTPM) was designed and successfully synthesized.AMTPM has both Si‐O and Schiff‐base structures.AMTPM can effectively improve the toughness of BD‐AMTPM resins through impact and tensile tests. [ABSTRACT FROM AUTHOR]

Highlights To improve the subpar lubricating performance of epoxy resin, this paper presents the preparation of a novel bimetallic phyllosilicate featuring a distinctive rice‐granular morphology, which incorporates nickel and iron metal cations through a facile hydrothermal process. These phyllosilicates were then integrated into the epoxy matrix to form composites. A comprehensive analysis of the target product validates the rationality of the synthesis strategy for the as‐prepared rice‐granular bimetallic nickel/iron phyllosilicate, demonstrating a homogeneous hierarchical structure with numerous tiny nanosheets of nickel/iron phyllosilicate grown in situ on the flat surfaces of the rice‐granular metal–organic frameworks. An adequate addition of nickel/iron phyllosilicates allows for excellent dispersion within the matrix and establishes strongly bonded interfaces, steadily increasing the elastic modulus and hardness. Notably, the average friction coefficients decrease from 0.515 for the pure resin to 0.450 for the composites when the filler content reaches 7%, indicating a significant solid lubrication effect. In contrast, adding just 1% nickel/iron phyllosilicate moderately improves wear resistance, elongation at break, and tensile strength. Furthermore, it was found that as the filler content increased, the weight loss rate was reduced by approximately 43.8%, while the residual char increased by 74.2%, significantly enhancing the thermal stability of epoxy composites at high temperatures. This study offers a promising approach to preparing self‐lubricated epoxy composites with favorable mechanical and thermal properties. NiFePS was successfully synthesized via a facile two‐step self‐polymerization. Excellent mechanical properties of composites could be achieved with low content of NiFePS. The friction coefficient and wear rate were lowered remarkably. The friction mechanism was solid lubrication. [ABSTRACT FROM AUTHOR]

A high‐power white laser source is prepared by using a 455 nm blue laser to excite YAG:Ce ceramics. To achieve high‐power output, a water‐cooling device is used to reduce the operating temperature of ceramics. The luminescence properties of laser‐excited phosphor ceramics are studied under different blue excitation power and different irradiation time. The experimental results show that the luminous flux of phosphor ceramics excited by the blue laser increases linearly with the increase of blue laser power, depending on the heat dissipation of the water‐cooling device. When the blue laser power increases to 73.1 W, the phosphor ceramics do not reach the luminescence saturation state. The luminous flux of phosphor ceramics excited by 73.1 W blue laser is stable within 60 min. The maximum luminous flux is 8094 lm, and the maximum working temperature of the ceramics is 110 °C. The experimental results show that water‐cooling packages are an effective means to realize high‐power white laser sources. [ABSTRACT FROM AUTHOR]

Aim is to explore the breadmaking potential for gluten‐free goods of non‐conventional starches from Andean crops ahipa, oca, and arracacha. Their characteristics and performance in breadmaking are compared with those of cassava, taken as a reference for conventional gluten‐free root starch. Physicochemical properties of breads are studied along with the pasting and thermal properties, composition, and α‐amylase hydrolysis of starches. Arracacha starch has the lowest amylose content (2.4%) and the highest water hydration (1.4 g g−1). Its batter shows adequate proofing, but the bread is highly adhesive, with dense crumb. Ahipa starch paste has the lowest peak, trough and final viscosities determined by rapid visco analyzer, and the highest hydrolysis rate (kRVA = 2.30 min−1). Its batter exhibits, along with oca, the highest volume increase during fermentation (193–197%), but structure collapses in the oven and no alveoli are observed in the crumb. Conversely, oca forms a crumb structure similar to cassava, but with higher cell density (131 alveoli cm−2), cohesiveness (0.95), and resilience (0.65) than the latter (71 alveoli cm−2, 0.88, and 0.45, respectively). Oca starch has lower pasting temperature (64 °C) and the starch paste has similar hydrolysis rate (kRVA = 1.92 min−1) compared to cassava (71.9 °C and 2.08 min−1, respectively), making it a suitable option for providing gluten‐free yeast‐leavened breads with improved technological properties and a comparable glycemic index. [ABSTRACT FROM AUTHOR]

Highlights This study investigated the effect of multi‐walled carbon nanotubes (MWCNTs) and reclaimed gypsum of varying contents on the mechanical properties and thermal stability of polypropylene (PP) composite materials. The results indicated that the incorporation of reclaimed gypsum and MWCNTs powder into PP composites could enhance the tensile strength, impact strength, and bending modulus of PP to a certain extent. The above properties of AGY/MWCNTs/PP composites were increased by 14.6%, 131.8%, and 36.2%, respectively, with the impact properties being significantly affected. Univariate analysis of variance revealed that MWCNTs powder and recycled gypsum exerted a significant impact on the mechanical properties of polypropylene composites. Moreover, the initial weight loss temperature of AGY/MWCNTs/PP demonstrated a notable increase, from 318.71 to 398.48°C, while the maximum weight loss temperature exhibited a comparable rise, from 406.85 to 461.54°C. The impact performance and thermal stability of polypropylene composite materials have been demonstrably augmented. A synergistic effect between reclaimed gypsum and multi‐walled carbon nanotubes in the reinforcement of polypropylene composites was demonstrated. This provides a theoretical framework and practical guidance for the design and preparation of high‐performance and recyclable polymer composites. [ABSTRACT FROM AUTHOR]

Silicene has recently been revisited as a 2D material with potential thermoelectric applications. Here, the thermal properties of supported silicene are determined by optothermal Raman spectroscopy. Single and multilayer silicene is grown either directly on silver (Ag) substrates or on an intermediate tin (Sn) monolayer, introduced to reduce the influence of the substrate on the physical properties of silicene. Experimental values of an effective cross‐plane thermal conductivity of 0.5 W/mK are obtained for silicene on Ag and 0.3 W/mK for silicene on stanene‐Ag. The values of the interfacial thermal conductance, on the other hand, are 0.3 and 0.5 GW/m2K, respectively. Heterostack engineering is confirmed as a versatile strategy for extracting relevant physical parameters in silicene and for modulating the thermal response in the 2D limit. [ABSTRACT FROM AUTHOR]

Levoglucosenone (LGO), a renewable compound obtained from cellulose biomass, has been utilized to prepare novel monomers bearing alkene functional groups. These monomer derivatives of LGO were subsequently cured via ultraviolet (UV)‐initiated radical thiol‐ene “click” chemistry with commercially available multifunctional thiols to obtain colourless, optically transparent cross‐linked thermosets. The monomers prepared in this work are unique due to utilising the internal double bond of the LGO ring during polymerization as part of the cross‐linked network. The thermal and mechanical properties along with the degradation of thermosets containing both ether and ester linkages within the LGO monomers were studied. These thermosets had tensile strengths of 1.3–3.3 MPa, glass transition temperatures between 23.2 and 27.2 °C, and good thermal stability of up to 300 °C. [ABSTRACT FROM AUTHOR]

Highlights Nowadays, non‐timber sources are of greater interest as they avoid deforestation and the pollution which occurs with cellulose obtention. An emerging alternative is using weeds such as windmill grass (Chloris spp.) to isolate cellulose since the plant grows in large quantities near crops or landfills used for farming. The present study aims to explore windmill grass as an alternative source of cellulose for applications as reinforcement in biopolymeric matrices. Treatment was conducted using the peroxyformic pulping method, varying the formic acid (FA) and hydrogen peroxide (HP) concentration to obtain an optimum cellulose extraction condition. The isolated celluloses were analyzed for chemical composition, yield, chemical functionality, crystallinity, and morphology. The optimum pulping condition (FA = 87.5%, HP = 3%) shows the gradual removal of non‐cellulosic components by microscopy. X‐ray diffraction analysis revealed a high crystallinity index (89.63%) with a characteristic cellulose type I pattern. To evaluate the reinforced effect of Chloris spp. celluloses, film formulations were made using sweet potato starch, glycerol, and cellulose at different concentrations (2.5, 5.0, and 7.5% w/w). The films' mechanical, physicochemical, and thermal properties were measured, and results indicate that adding cellulose fibers significantly improves these properties of sweet potato starch films, revealing further applications and non‐wood windmill grass added value with potential applications in the packaging sector. Windmill grass (Chloris spp.) is presented as a non‐wood source of cellulose. The peroxyformic method is reported as a less polluting cellulose extraction process. Optimal cellulose pulp presents enhanced physicochemical properties after bleaching. Cellulose‐reinforced sweet potato starch films exhibit a stable biopolymeric matrix. The films produced show enhanced water barrier and mechanical/thermal properties. [ABSTRACT FROM AUTHOR]

Carbon materials comprise a wide range of microstructures and excellent electrical and thermal properties while being cost‐effective and readily available. They can be obtained through carbothermal processes at high temperatures, starting from cellulose. Catalytically active compounds, for example, iron salts, strongly influence the carbon microstructure during the graphitization process. Different degrees of structural order can, therefore, be achieved by adjusting the concentration of the iron salts. An infusion withdrawal impregnation approach is used on filter paper to prepare a continuous gradient of the carbon microstructure. This structural change is accompanied by a continuous variation of the closely related electrical and thermal transport properties. Even more, the synergistic interplay of local sheet resistance and thermal diffusivity results in the formation of switchable temperature gradients when an external current is applied. Steady state temperature differences of up to 80 °C are observed along the centimeter‐scaled samples. The controllable temperature gradient formation will be of great interest for applications requiring a fast temperature screening. Furthermore, the temperature gradient can be imposed onto other materials, which will be particularly relevant for advanced thin film characterization applications. [ABSTRACT FROM AUTHOR]

Background Results Conclusion Fried dough sticks, widely enjoyed in southeast Asia, are made by frying a mixture of wheat flour and water at high‐temperature. With the move towards industrial production, there is an increasing demand for healthier versions. Understanding the key properties of fried dough sticks and how the ingredients interact is crucial for meeting these health‐focused consumer preferences.In this study, the connections between the dough's rheological and thermal properties, alongside the interactions between gluten proteins and the oil content in fried dough sticks, were examined and analyzed at varying gliadin to glutenin mass ratios (Gli/Glu). The results indicated that a general decrease in the viscoelastic properties of the dough was associated with an increase in the Gli/Glu ratio. Furthermore, a heightened concentration of gliadin was observed to augment the mass loss of gluten proteins, thereby engendering a spatially sparse network structure. Additionally, this excessive presence of gliadin precipitated the thermal instability within the dough, necessitating an augmented chemical force to preserve the stability of the gluten network structure.At the Gli/Glu ratio of 5:5, the gluten protein exhibited enhanced thermal stability and minimal mass loss. At this specific ratio, the gluten network was characterized by a comparatively high prevalence of extended gluten films and short‐chain structures, which resulted in the production of fried dough sticks possessing minimal structural oil content. The study provided a theoretical basis for identifying the Gli/Glu ratio as an effective approach to modulate the oil content in fried dough sticks. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Halide perovskites emerge as promising candidates for thermoelectrics due to their ultralow thermal conductivity. The conventional theory based on the phonon gas model, which treats thermal transport as particle‐like behavior, shows limitations to describe the unusual thermal transport property in some halide perovskites with strong anharmonicity. Here, the significance of phonon coherence effect on thermal transport of bismuth‐halide perovskite Cs3Bi2Br9 is reported by inelastic neutron scattering and simulations including density functional theory and machine‐learning potential based molecular dynamics. This study shows that the restrictive low‐energy acoustic phonons lead to the limited particle‐like thermal conductivity, which seriously underestimates the lattice thermal conductivity of Cs3Bi2Br9. The significant contribution of wave‐like optical phonon modes, driven by the coherence effect, accounts for an additional ≈50% wave‐like thermal conductivity. Besides, the experimental weak temperature dependence of thermal conductivity along z direction (κ ≈T−0.35) is well reproduced by calculation (κ ≈T−0.37) when including phonon coherence. This work highlights the critical role of phonon coherence in Cs3Bi2Br9 and enhances understanding on the unusual thermal transport properties in halide perovskites and other related materials with strong anharmonicity. [ABSTRACT FROM AUTHOR]

While improving the thermal conductivity of composites, single‐size carbon nanotubes (CNT) often degrade their mechanical properties due to the agglomerates. To overcome this limitation, this study reported thermoplastic resin matrix composites synergistically reinforced with small, medium, and large‐size carbon nanotubes (S‐CNT, M‐CNT, and L‐CNT). Using the thermal conductivity (λ) and mechanical properties (flexural strength [F], compressive strength [C] and tensile strength [T]) as the response values, we conducted 21 sets of mixing design experiments and developed the associated quadratic term models. Further multi‐objective optimization was carried out for the above response values. Optimized multiscale CNT synergistically modified composites (S‐CNT, M‐CNT, and L‐CNT contents of 1.25, 7.02, and 2.56 wt%) exhibited a λ value of 1.168 W/mK, which was 121% higher than that of pure composite and also superior to the same content of S‐CNT‐ (1.031 W/mK), M‐CNT‐ (1.016 W/mK), and L‐CNT‐modified composites (0.983 W/mK). Additionally, the optimized composite demonstrated excellent mechanical properties (F = 1482 MPa, C = 848 MPa, and T = 1759 MPa), which were 13%, 11%, and 13% higher than those of the pure composites, respectively, and also surpassed those of the S‐CNT‐, M‐CNT‐and L‐CNT‐modified composites. Highlights: Using three different scales of carbon nanotubes modified CF/PPBESK composites.Polynomial modeling of composite's thermal conductivity and mechanical properties.Synergistic interactions between carbon nanotubes to improve the composite's thermal conductivity and mechanical properties. [ABSTRACT FROM AUTHOR]

The relationship between interfacial structure and thermal conductivity in epoxy resin/Al2O3 composite is important but is still elusive. Here, we illuminate this issue by investigating the role of four silane coupling agents in thermal conductivity for epoxy resin/Al2O3 composites. The results show that 3‐glycidoxypropyltrimethoxysilane (KH560) is the best silane coupling agent to modify Al2O3, resulting in the lowest viscosity and the highest thermal conductivity of the epoxy resin/Al2O3‐KH560 composite compared with alternative systems. This is attributed to the strong interfacial interaction between Al2O3‐KH560 and epoxy resin, as confirmed by the Fowkes model and broadband dielectric spectroscopy. The interfacial thermal resistance between the epoxy resin and Al2O3 is also quantitatively measured via a photothermal radiometry technique. The epoxy resin/Al2O3‐KH560 also has the lowest interfacial thermal resistance (1.50 ± 0.02 × 10−6 m2 K W−1), compared with the other three systems. This study advances the understanding of the relationship between interfacial structure and thermal conductivity in polymer composites. Highlights: The relationship between interfacial structure and thermal conductivity in epoxy resin/Al2O3 composite is understood.The interfacial structure is characterized by broadband dielectric spectroscopy.The interfacial thermal resistance is quantitatively measured via a photothermal radiometry technique. [ABSTRACT FROM AUTHOR]

Highlights In this electronic era, there is a demand to switch from conventional polymers to conducting biopolymers. We developed conducting biopolymer nanocomposites of cashew gum (CG) and polypyrrole (PPy) with zinc oxide (ZnO) nanofillers [CG/PPy/ZnO] via in‐situ oxidative polymerization using a sustainable solvent. These nanocomposites were characterized using Fourier‐transform infrared spectroscopy (FTIR), UV–visible spectroscopy, field emission scanning electron microscope (FE‐SEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The FTIR signal at 855 cm−1 confirms the successful inclusion of ZnO nanofillers into the biopolymer. UV–vis absorption of the blend nanocomposite increases with the nanoparticle doses. Among the various blend nanocomposites, the least bandgap energy was observed for 7 wt% ZnO loading. FE‐SEM revealed homogeneous dispersion of ZnO nanofillers in the CG/PPy blend at 7 wt% ZnO. TGA and DSC demonstrated that the CG/PPy/ZnO nanocomposites have better thermal stability and glass transition temperature than the pure polymer blend, indicating enhanced thermal properties. The CG/PPy/7 wt% ZnO showed the highest conductivity, 4.62 times greater than the pristine blend at 100 Hz. Dielectric constant, activation energy, AC conductivity and dielectric loss measurements demonstrated that the nanocomposites outperformed the pure polymer blend. Complex impedance analysis revealed increased impedance with rising temperature. Overall, CG/PPy/ZnO nanocomposites exhibit superior optical, morphological, thermal, electrical, and dielectric properties, making them promising for energy storage and optoelectronic applications. Ecofriendly synthesis of CG/PPy/ZnO nanocomposites Enhancement in optical, structural, and thermal properties of CG/PPy/ZnO Dielectric properties and temperature‐dependent AC conductivity are summarized. Blend nanocomposite shows higher AC conductivity and dielectric constant CG/PPy/ZnO nanocomposites are suitable for energy storage applications [ABSTRACT FROM AUTHOR]

Whey protein hydrolysates, derived from enzymatic hydrolysis of whey protein isolates or concentrates, offer enhanced bioavailability and solubility compared to intact whey protein. In this study, whey protein hydrolysates (WPHs) having different hydrolysis degrees (5%, 10%, and 15%) were produced and muffin cakes were enriched with the addition of WPHs. In general, the addition of WPHs showed a significant effect on oil and protein content while the emulsion activity was improved with the increased hydrolysis degree (HD). The degree of hydrolysis increment resulted in a significant increase in both antioxidant power and antiradical activity of the WPHs. Ferric‐reducing antioxidant power and ABTS radical scavenging activity ranged between 18.83–87.27 mg TE/100 g and 211.8–5063.1 mg TE/100 g, respectively. The highest FRAP and ABTS values were recorded for the 15% HD while the lowest was for the native whey protein isolate (WPI). The induction periods giving a clear information for the oxidative stability were 1593 min for the control muffins, and it was 1654 for the muffin added with WPI. Rheological data revealed that all cake batter samples including WPHs showed viscoelastic behavior. WPHs could be efficiently used in muffin formulation to increase the biofunctional effects of the final products. [ABSTRACT FROM AUTHOR]

Liner materials have extensive applications in automobile industry, packaging, and aeronautics. One of the specific uses of such materials is in thermal barrier, coating rockets, missile, and other systems used in space and defense. Each liner material exhibits different properties according to their chemical structure and composition. In this study, accelerated thermal aging of the liner material, silicone‐hollow glass microsphere composite (SHGC) has been studied along with the determination of its life span. The effect of such aging on the thermal properties of SHGC has been studied using thermogravimetry. Activation energy of the process has been determined to be in the range of 45–55 KJmol−1. The results have been compared with already reported silicon polymers. Shelf‐life of SHGC composite has also been determined using Arrhenius model. Stochastic model has been applied to determine the lower and upper limits of shelf‐life. Shelf‐life of SHGC is found to be 24 years with 28 and 18 years of upper and lower error limits. [ABSTRACT FROM AUTHOR]

In this study, graphene nanoplatelets were applied to polyester fabrics using the knife‐coating method at different concentrations (50, 100, and 150 g/kg). SEM, DSC, and TGA/DTG analyses were performed. The influence of graphene coating on hydrophobicity and surface roughness was examined by water contact angle (WCA) measurement and root mean square roughness, respectively. Abrasion resistance and tear strength tests were also performed. The effect of graphene used as a filler on the flammability of polyester fabric was evaluated for the first time according to the BS 5852 standard. No significant weight loss (only in the range of 0.4%–1.5%) was observed in the graphene‐coated samples even after 100,000 cycles. While the WCA value was 0 for the uncoated fabric, the blind coating and maximum graphene‐coated sample measured 86° and 95°, respectively. The coating process reduced the roughness of the base fabric, and the decrease continued with the increasing graphene ratio. The tear strength values that were 45.5 N in the warp and 53.6 N in the weft direction in the blind coating, increased to 52.2 and 59.1 N, respectively, at the maximum graphene concentration. Graphene coating enhanced thermal stability, increased hydrophobicity, and improved flame retardancy in the test using a smoldering cigarette. [ABSTRACT FROM AUTHOR]

Highlights By applying an electric field, the thermal conductivity(λ) of composites can be enhanced through the induced orientation of high λ fillers within the matrix. As far as the DC electric field is concerned, the pattern of the electric field application time on the λ of the composites is not clear. In this work, a 400 V/mm DC electric field was selected to prompt the alignment of boron nitride (h‐BN) within the epoxy resin (EP) matrix, with an in‐depth analysis of how the timing of the electric field application influences the λ of the composites. Results demonstrate that the λ of h‐BN/EP composites exhibits a pattern of increasing, decreasing, then increasing and finally stabilizing when the electric field application time is 0–480 min. When the electric field was applied for 20 min, the composites exhibited a maximum λ of 0.544 W/(m K), a value that is 3.88 times of pure EP, and 2.32 times of that of the composites without electric field under the same filling content. In addition, the composite exhibits an AC breakdown field strength (Eb) that is slightly elevated compared to the pure EP. Boron nitride (h‐BN) was successfully oriented in epoxy resin (EP) matrix by electric field induction. λ of the composite is proportional to orientation Angle of h‐BN in the matrix. λ of composite can be increased by electric field induced fillers orientation. Electric field induction does not damage the insulation properties of composite. The excellent in‐plane λ and insulation properties of h‐BN are fully utilized. [ABSTRACT FROM AUTHOR]

Difunctional glycidyl azide polymer (GAP) is an energetic binder promising for propellant formulations. The multifunctional fluorine‐containing GAP has been synthesized to enhance its mechanical properties. This work outlined multifunctional GAP partially grafted with 1,2,3‐triazole‐5‐(α‐hydroxyl)‐fluorinated polyether (GAP‐g‐3F) synthesized by thermal and catalyst‐free azide‐alkyne cycloaddition reaction, in which the azide groups were from GAP and electron‐deficient alkynes from β‐propargyl‐α‐hydroxyl poly (tri‐fluoropropane glycidyl ether) (PHP3F). PHP3F was synthesized via the typical cationic ring‐opening polymerization of 2‐((2,2,2‐trifluoroethoxy) methyl) oxirane and propargyl alcohol as the initiator. The chemical structures, molecular weight, and thermal properties were characterized by FTIR, NMR, GPC, DSC, and TGA, respectively. HNMR results showed that 8 % of total azide groups in GAP were grafted. GAP‐g‐3F had a slightly higher glass transition temperature than that of GAP. The results of TGA showed that GAP‐g‐3F had suitable thermal decomposition resistance up to 200 °C. The thermal properties, mechanical properties, cross‐linking network structures, and microstructures of the polyurethane networks cured with hexamethylene diisocyanate trimer as a crosslinking agent were determined and compared by TGA, universal tensile test, swelling measurement, and SEM, respectively. The initial decomposition temperature of GAP‐g‐3F‐based polyurethane networks (GAP‐g‐3F‐PU) was around 220 °C, thus meeting the requirements for propellants. In addition, GAP‐g‐3F‐PU exhibited superior mechanical properties, showing an almost twelvefold increase in tensile strength to 16.9 MPa compared with difunctional GAP‐PU with 1.4 MPa tensile strength. The results of the swelling measurement revealed that the GAP‐g‐3F‐PU sample showed a higher crosslinking density in comparison to the GAP‐PU sample. SEM results indicated that the multifunctional fluorine‐containing GAP could enhance compatibility between the soft and hard segments of polyurethanes, leading to a decrease in their separation degree. This finding showed that the synthesis of a multifunctional GAP partially grafted with fluorinated polyether via a triazole ring may be a promising solution to decrease the separation degree increase of PUs, thereby improving the mechanical properties. [ABSTRACT FROM AUTHOR]