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Summary: The influence of the incorporation of hydrophobic nanosilica on morphological and mechanical properties of polyamide 6 (PA) and poly(propylene) (PP) blends has been investigated. Depending on the amount of silica nanoparticles in the blend and the melt mixing procedure, a strong refinement of PP (as minor dispersed phase) droplet size can be achieved thanks to the interfacial confinement of nanoparticles. The accumulation of nanoparticles at the interface allows the formation of an anti-coalescence rigid barrier around PP domains that prevents/refrains dispersed phase domains from coalescence as highlighted by transmission and scanning electron microscopies. The mechanical properties of the hybrid blends were also discussed and interpreted in relation with the blend morphology. [ABSTRACT FROM AUTHOR]

The textile industries are looking forward to sustainable textile products. The bio‐based products are very important for protecting the environment, reducing carbon emissions, eliminating chemical pollution, and preserving the resources. These products provide economic advantages and strengthen communities with customer expectations for environmentally friendly items. In addition, sustainable practices encourage innovation and contribute to a healthier and adaptable environment, making them an essential textile product. Here the natural flax fiber plays a vital role due to its eco‐friendly behavior. Cotton‐flax blended yarns are manufacturing for perfect use of natural fibers and getting the better quality yarn than single product yarn. Here in this work it was trying to find out the perfect blending ratio by using Design‐Expert software. Because different blended ratio contain different characteristics. So it was trying to find out a perfect blending solution from the thirteen different ratios by using Design‐Expert software. This software analyses the blended ratios through statistical analysis. This study focuses on the unevenness (U%), imperfection index (IPI), hairiness (H%), tenacity (cN/tex) and elongation at break of the blended yarn. During the analysis the actual and predicted values were checked and it shows good significance, the correlation and regression analysis highlight the results of the samples summary. The findings of the study have great impact on the quality of cotton‐flax blended yarn, which impact on the quality of textile products. This work not only helps to understand cotton‐flax blending using Design‐Expert software, but it also highlights the possibility of using the perfect blended ratio by giving a solution. Highlights: To identify the perfect blended ratio of flax and cotton fiber for producing blended yarn.Design‐Expert software has been used to find out the perfect response through yarn properties surface methodology.Thirteen experimental runs were trailed to find the perfect result. [ABSTRACT FROM AUTHOR]

This study aims to investigate the flame retardancy and mechanical properties of polypropylene (PP)‐based intumescent flame retardants (IFRs) consisting of melamine phosphate (MP) and pentaerythritol (PER), and different additives; boron phosphate (BP), antimony oxide (AO), and preceramic polymers, namely poly(dimethylsilane) (PDMS) and poly(methylsilsesquioxane) (PMSQ). The composites were produced by twin‐screw extrusion, and then molded by injection molding. Their characterizations were performed with limiting oxygen index (LOI), horizontal burning tests, thermogravimetric analysis (TGA), tensile and impact tests. The total amount of IFRs and the additives in polypropylene was kept constant at 20 wt%. The additive concentration was varied as 1, 3, and 5 wt% in the composites. The highest LOI value of 29% was obtained for PP/MP/PER composite with MP/PER ratio of 3/1. PP/IFR‐based composites with 1 wt% additive exhibited higher LOI and horizontal burning performance than the other composites with 3 and 5 wt% additives. It is revealed that tensile modulus and impact strength of neat PP were improved with the addition of IFRs, and for each type and amount of the additives used in the study. Highlights: Usage of IFRs, preceramic polymers, BP and AO in PP improved flame retardancy.Lower amount of additives (1%) in PP/IFR composites led to higher LOI values.Additive incorporation enhanced tensile modulus and impact strength of neat PP. [ABSTRACT FROM AUTHOR]

Grafting polymers with reactive maleic anhydride is a common approach for the synthesis of new material with the capability of acting as a compatibilizer in polymer blends. Accordingly, this research showed a new approach for grafting maleic anhydride onto renewable cellulose acetate using an initiator. The grafting process through extrusion showed good stability with continuous production of all grafted samples. Moreover, two different grafting processes, namely one‐step and two‐step processes, were shown to produce materials with very similar characteristics. Grafting of maleic anhydride onto cellulose acetate by reacting with its hydroxyl groups was confirmed by both Fourier transform infrared spectroscopy and nuclear magnetic resonance analysis. Rheological studies also demonstrated the enhanced flowability and lower viscosity of the grafted material in comparison to the plasticized cellulose acetate. Highlights: Grafting maleic anhydride onto plasticized cellulose acetate by reactive extrusion.Detection of grafted maleic anhydride onto cellulose acetate through NMR analysis.High thermal stability of grafted materials.Significant reduction in viscosity of plasticized cellulose acetate after grafting [ABSTRACT FROM AUTHOR]

In order to study the effect of curing temperature on the shape memory properties (SMPs) of GO‐CF hybrid‐reinforced SMPCs, eight sets of composites were prepared at different curing temperatures (60, 70, 80, 90, 100, 110, 120, and 130°C). The rheological and curing properties of the matrix, and the apparent density, porosity, microstructure, and SMPs of the composite were measured and analyzed, respectively. The results showed that at 100°C, the composite has the highest apparent density (1.52 g/cm3), the lowest porosity (0.47%), the best SMPs, the shape fixed rate of 99.13%, the shape recovery rate of 96.54%, and the maximum shape recovery force (5.15 N). The shape recovery speed and rate of shape recovery are also the fastest. This is because when the curing temperature is 100°C, the viscosity of the matrix can be kept at a low level, and the curing reaction rate is appropriate. This not only ensures that the matrix can be fully infiltrated into the fiber space but also obtains the matrix with appropriate crosslinking degree. Therefore, the microstructure of the prepared composite is ideal, which makes the matrix has a strong ability to restrain the expansion force of the fiber and a high efficiency of the transfer force and heat. Finally, in the test of SMPs, the composite showed higher SMPs. It was concluded that the SMPs of the composites were mainly affected by the infiltration effect of the matrix in the fiber. Highlights: The microstructure of the composite was more ideal at 100 °C.The composite with the lowest porosity has the best shape memory properties.The high porosity weakens the heat and force transfer ability of the matrix.The shape memory properties of composites are the best prepared at 100 °C. [ABSTRACT FROM AUTHOR]

Membrane‐based CO2 separation is vital for various applications such as biogas upgradation. Polymer membranes are employed for CO2 separation in the industry. Polymer membranes have a trade‐off between selectivity and permeability. Blending polymers is an emerging approach for altering the gas transport in the membranes. This work investigates the fabrication and characterization of blended biodegradable cellulose acetate (CA) with polyimide (PI). Thermal stability was characterized using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), and functional groups were analyzed using Fourier transform infrared spectroscopy (FTIR). The morphology of membranes is analyzed using field‐emission scanning electron microscope (FESEM). The blend membranes were tested for separation of CO2 from model biogas (CO2/CH4) at room temperature and a low feed pressure (∼1.5 bar). The CA:PI blend membrane composed of 93% CA and 7% PI showed CO2 permeability of 19.71 Barrer, approximately 206% greater than pure CA, and CO2/CH4 selectivity was 9.42. Experimental results are compared with literature on CA‐based membranes. Highlights: Blend membrane of cellulose acetate (CA) and polyimide (PI)CO2/CH4 gas permeation testing of membranes using a model biogas mixtureBlend membranes exhibit 206% higher CO2 permeability than pure CA membranesBlend membranes demonstrated enhanced CO2/CH4 selectivity of 9.42. [ABSTRACT FROM AUTHOR]

Fuel cells are gaining increasing importance as a promising alternative to traditional energy sources, primarily due to their exceptional efficiency and environmental advantages. The electrical performance of proton exchange membrane fuel cells (PEMFCs) largely depends on the effectiveness of proton and electron transport within the cell components. A critical factor impacting this efficiency is the electrical conductivity of polymer‐based bipolar plates (BPPs), which play a fundamental role as current collectors. BPPs in PEMFCs can be made from various materials including coated metallic materials, graphitic materials, and polymer composites. This review exclusively concentrates on polymer composite BPPs. Enhancing the overall cell performance is achievable through the integration of electrically conductive additives into the polymer matrix of these plates. Graphite (GR), carbon black (CB), carbon fibers (CF), carbon nanotubes (CNT), and graphene (Gr) all emerge as highly promising functional materials capable of substantially elevating BPPs performance. This study, among its various objectives, delves into the synergistic effects of these electrically conductive additives and their capacity to enhance the electrical conductivity within polymeric matrices. Furthermore, this review article thoroughly explores the influence of the polymeric matrix, encompassing co‐continuous morphology and processing conditions. In essence, it focuses on the improvement of BPPs electrical conductivity through innovative designs of their polymer‐based composites and nanocomposites and the particular selection of the electrically conductive fillers. The insights derived from this study significantly contribute to a more profound understanding of how to effectively harness the potential of this vital PEMFC component. [ABSTRACT FROM AUTHOR]

Shapeable and flexible pressure sensors with superior mechanical and electrical properties are of major interest as they can be employed in a wide range of applications. In this regard, elastomer‐based composites incorporating carbon nanomaterials in the insulating matrix embody an appealing solution for designing flexible pressure sensors with specific properties. In this study, PDMS chains of different molecular weight were successfully functionalized with benzoxazine moieties in order to thermally cure them without adding a second component, nor a catalyst or an initiator. These precursors were then blended with 1 weight percent of multi‐walled carbon nanotubes (CNTs) using an ultrasound probe, which induced a transition from a liquid‐like to a gel‐like behavior as CNTs generate an interconnected network within the matrix. After curing, the resulting nanocomposites exhibit mechanical and electrical properties making them highly promising materials for pressure‐sensing applications. [ABSTRACT FROM AUTHOR]

A portable lab scale test setup (1 × 1 × 0.72 m3) with apparatus and procedure has been illustrated to test the fire extinguishability of fire retardant materials (FRMs) as water additives on class A fires. The main objective was to use selected commercial, eco‐friendly FRM powders such as hydroxides, carbonates, and clays as water additive‐based fire extinguishing agents for suppressing solid fires. FRM powders, namely, Mg(OH)2, Ca(OH)2, CaCO3, and MMT‐Clay were added to water and were mist sprayed on a wooden fire (class A) to test their fire‐suppressing ability. A comparison involving tests with only water (without any additives) was also recorded. The solutions made with FRM additives in water showed promising results in suppressing the fire in comparison to systems with only water as an extinguishing agent. Heat sink materials, such as hydroxides and clays depicted commendable performances in retarding the burning process and almost doubled the capability of fire suppression with low loading. Their heat‐absorbing nature resisted the increase in temperature and slowed down the burning process causing an increase in the total burning time of the crib and avoiding reignition. Whereas, carbonates (CaCO3) showed a faster flame out by the release of CO2 gas, which diluted the oxygen content in the surroundings. The article concludes with a discussion of the requirements for the ideal water mist additive‐based fire extinguishing agent and a recommendation that future work include validation of the laboratory‐scale method based on a comparison with full‐scale suppression data for the same additives. [ABSTRACT FROM AUTHOR]

This study aimed to reveal the effect of expanded perlite (EP) additive as a flame retardant for acrylonitrile‐butadiene‐styrene (ABS) copolymer based composites. Before composite preparation, fine powdered EP was characterized by Fourier transform infrared spectroscopy, x‐ray diffraction, thermogravimetric analysis, and scanning electron microscopic analyses. Also, maleic anhydride grafted ABS (MAH‐g‐ABS) with a grafting degree of 3.9 wt% was synthesized and used as a polymeric compatibilizer. ABS/EP composites with different ratios of EP were prepared by a continuous one‐step melt mixing method. Thermogravimetric and morphological analysis, tensile tests, limiting oxygen index (LOI) and UL‐94 vertical burning tests of the composite materials were investigated. EP significantly decreased the decomposition rate of ABS and promoted char formation. EP provided a UL‐94 V‐1 flammability rating with great fire resistance and self‐extinguishing properties to the ABS matrix without any melt dripping. The LOI of ABS was greatly improved, reaching a value of 28.5% by adding only 5 phr EP. Zinc borate (ZB) also played a significant role in enhancing thermal stability and flame retardancy by creating a good synergism with EP. The composite containing 5 phr ZB showed a flame retardant grade of UL‐94 V‐0 and an LOI value of 27.5%. Highlights: Flame retardant ABS/EP composites were successfully prepared by melt mixing.The EP ratio of 10 phr provided the highest resistance to flammability.ZB showed good synergy with EP in enhancing the flame retardancy of ABS.ABS/EP10/ZB‐5 composite had a UL‐94 V‐0 rating with an LOI value of 27.0%.This study proved the potential use of natural EP as a flame retardant filler. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA)‐based thermoplastic vulcanizates (TPVs) were fabricated using dynamic and static vulcanization in the presence of untreated and surface‐treated zinc oxide (ZnO). Initially, the effect of chloroprene rubber (CR) as the elastomeric phase in the PLA‐based thermoplastic elastomer (TPE) was tailored. The CR content varied from 20 to 40 wt%, leading to 46%–70% and 19%–76% decrement in tensile strength and modulus, respectively, while elongation at break increased up to 9–13 times, highlighting the soft rubber phase's impact on ductility. Impact resistance testing showed improved toughness with CR addition, peaking at 20 wt% CR. Scanning electron microscopy (SEM) revealed matrix‐dispersed morphology with increasing CR droplet size, and co‐continuous morphology at 40 wt% rubber in BP6R4. In the next step, the optimized TPE was selected, and the focus shifted to investigate the effect of dynamic/static vulcanization on mechanical properties. It is revealed that adding modified ZnO (ZnO60) increased melt torque, but it decreased after 1.5 min. All vulcanized samples exhibited lower tensile strength and elongation at break but higher elastic modulus due to metallic particle reinforcement. ZnO particle agglomerates and rubber aggregations led to lower mechanical properties. These findings offer quantitative insights into vulcanization's influence on PLA‐based TPVs, informing partially biobased TPEs development and addressing vulcanization limitations. Highlights: Fabrication of biobased thermoplastic elastomer (TPE) and thermoplastic vulcanizate (TPV) based on polylactic acid/chloroprene rubber (PLA/CR) shows the sustainable material prospect.The effects of dynamic/static vulcanization on TPE's behavior are investigated.Micro‐morphology analysis showed dispersed CR phase in TPEs when PLA content is <40 wt%.The addition of modified ZnO through static vulcanization minimized degradation.ZnO Agglomeration and CR aggregations caused subpar TPV mechanical properties. [ABSTRACT FROM AUTHOR]

In the past few years, epoxy resins utilization has gained much significant recognition from researchers worldwide as a result of its advantages in different sectors such as automotive, aerospace, electronic systems, constructions, and other related fields because of its outstanding mechanical performance, corrosion protection, and dielectric properties. The nanomaterials incorporation into the matrix has been duly examined to be the most productive route to enhance polymer composite's mechanical properties. Despite that, the inherent brittleness, relatively low fracture toughness, cross‐linking ability, poor electrical, and thermal properties of epoxy render it weak to growth and initiation of cracks, limiting its utilization in state‐of‐the‐art structural applications. Especially, epoxy is flammable while releasing a considerable amount of gases and smoke, thus, extending a potential risk to lives. Consequently, several nanofiller materials like graphene (Gr), transition metal dichalcogenides, MXene, and hexagonal boron nitride (h‐BN) produce extensive chances to equip multi‐functional characteristics and then reinforce the epoxy resins for the state‐of‐the‐art application. With this current review, the present literature investigation of epoxy filled with nano‐sized material has been examined thoroughly. Current advances in the approach of integrating nanosized materials in the epoxy matrices have been also introduced. Most significantly, anti‐corrosion, mechanical, and flame‐retardant properties of nanomaterials reinforced epoxy nanocomposites have also been reviewed in particular. Ultimately, the present statuses of the field in addition to the future approach have been considered concerning the usefulness of numerous nanofillers toward reinforcement of epoxy in construction and building materials. The expectation in this extensive review could produce a valuable reference, ingenuity, and guidance for researchers in this area of study. [ABSTRACT FROM AUTHOR]

Fire retardancy for textiles is important to prevent the rapid spread of fire and minimize damage to property and harm to human life. To infer fire‐resistance on textile materials such as cotton or nylon, chemical coatings are often used. These chemicals are usually toxic, and economically and environmentally unsustainable, however, some naturally produced protein‐based fire retardants could be an alternative. A biofilm protein from Bacillus subtilis (BslA) was identified and recombinantly expressed in Escherichia coli with a double cellulose binding domain. It was then applied to a range of natural and synthetic fabric materials. A flame retardancy test found that use of BslA reduced fire damage by up to 51% and would pass fire retardancy testing according to British standards. It is therefore a viable and sustainable alternative to current industrial fire‐retardant coatings. [ABSTRACT FROM AUTHOR]

Since the advent of supporting matrices for biological applications, many types of drugs have been administered via various forms of conventional drug delivery preparations, such as pills, solutions, creams, suppositories, injected gels and so on. Key parameters to all these systems for effective drug delivery are controlled release for sustained periods, targeted delivery, and enhancements of drug stability and efficacy, all of which can be manipulated by using polymers. Given the important impact of the structures of the polymers on these parameters, this mini‐review gives a simple introduction to the requirements of drug delivery systems and surveys the synthetic pathways to a key polymer in this field, namely poly(lactic acid). We also review the preparation of block copolymers that incorporate poly(lactic acid), to expand and further develop its properties for drug delivery systems. It is hoped that this short teacherly and introductory review will provide a basic stepping‐stone to more in‐depth reviews and papers and enable an easy access to this fast growing field. © 2023 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

The properties including combustibility, rigidity, thermal conductivity, and the color of the fiber sample influence the flammability characteristics of composite materials. Although the influence of phosphorus‐based fire retardants on the flammability characteristics of glass fiber‐based composite materials has been well studied, there is a need to better understand the effects of these fire retardants on the flammability characteristics of carbon fiber‐based composites. In the current study, four different commercially available phosphorus compounds (melamine polyphosphate (MPP), 9, 10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene10‐oxide (DOPO), aluminum diethyl phosphinate (AlPi), and zinc diethyl phosphinate (ZnPi)) are used. The flammability test results indicate that UL‐94 V rating maintains to burn to clamp with the addition of MPP, DOPO, and ZnPi in all concentrations. The highest UL94 V rating of V0 is obtained with the addition 10 wt% AlPi. An increase in LOI value is observed in samples containing MPP, AlPi, and DOPO. The highest LOI value of 41.5% is observed with the addition of 20 wt% AlPi. According to the MLC results, the lower peak heat release rate (pHRR) and total heat evolved (THE) values are obtained with the addition of all studied phosphorus compounds. The lowest pHRR (157 ± 10 kW/m2) and THE (44 ± 5 MJ/m2) values are obtained with the use of 20 wt% MPP and DOPO, respectively. The highest fire performance index (FPI) is achieved with the use of AlPi. Apart from DOPO which shows its effect predominantly in the gas phase, the studied phosphorus compounds exert flame retardant action both in the condensed and gas phases. [ABSTRACT FROM AUTHOR]

Improving the flame retardancy and lightweight of fluorosilicone rubber (FSR) foam is important for its application in aerospace, rail transportation, petrochemical equipment, etc. In this work, ammonium polyphosphate (APP) and expandable graphite (EG) were used as synergistic flame retardants, and the lightweight FSR composite foam with flame retardancy was prepared by supercritical N2 foaming. When there were 12.5 phr APP and 7.5 phr EG, the composite foam with density of 0.254 g/cm3 showed superiority in foaming performance and flame retardancy, and the limit oxygen index was 36.4%, the UL‐94 grade reached V‐0, the ignition time was 12 s and the fire performance index was 0.071 s·m2/kW. In addition, the aging, oil and solvent resistance of FSR foam was not affected. This work provided data support for the production and application of the flame retardant FSR foam. [ABSTRACT FROM AUTHOR]

The crystallization properties of polypropylene (PP), a widely used polymer in industry, can be modified to overcome its mechanical limitations. In the current work, we investigated the effect of ethylene octene copolymer (EOC), blend morphology, nanoclay loading, nano‐localization, and component ratios on PP/EOC crystallization behavior in various aspects, including crystallization rate, degree of crystallinity, nucleation state, and crystalline phases. The results revealed that adding EOC with varying ratios can decrease PP crystallinity both in degree and rate due to the partial miscibility of components through grafting. Furthermore, it was found that the effect of the nanoclay on the crystallization behavior of PP is dependent on the nanoclay loading and its localization in the blend. The nanoclay, therefore, served as a nucleation agent at low nanoparticle contents, accelerating the crystallization rate regardless of the blend's microstructure. However, the crystallization rate of the blend samples at high nanoclay contents (above the rheological percolation threshold) was strongly influenced by the type of morphology. Accordingly, high nanoclay concentrations in blends with matrix‐dispersed morphologies reduced crystallization rates (increasing half‐time from 164 to 216 and 186 s), primarily because PP chains slowed down due to their interactions with nanoparticles and nanoclay hindrance. In contrast, in a blend with a co‐continues‐type morphology, the crystallization rates increased (decreasing half‐time from 624 to 270 and 236 s) due to nano‐localization at the interface and morphology transformation to the matrix‐dispersed one. The blends and nanocomposites based on PP/EOC were also investigated to determine the relationship between the crystallization behavior and mechanical properties. [ABSTRACT FROM AUTHOR]

In this study, we presented a one‐step melt‐blending method to fabricate polypropylene (PP)/polycarbonate (PC) light‐diffusing materials. A promising balance between haze and transmittance was obtained by the addition of small amount of PC to the matrix. On the basis of Mie scattering theory and morphology analysis, the correlation between processing conditions and light‐diffusing properties was built. Low rotor speed and high viscosity ratio were beneficial to optical properties of PP/PC composites. To extend the advanced application, two general anti‐ultraviolet additives nanoscale titanium dioxide (Nano‐TiO2) and 2‐(2‐hydroxy‐5‐methylphenyl) benzotriazole (UV‐P) were added to impart UV‐shielding property to the composites. Their specific influences on the morphology and comprehensive properties of PP/PC composites were studied. It was found that the introduction of Rayleigh scattering raised by Nano‐TiO2 could strengthen the scattering effect and cause a significant reduction in light transmittance, while UV‐P had little effect on the optical properties of the light‐diffusing composites. In summary, this study prepared the PP/PC composites with high‐performance light scattering and UV‐shielding properties applying a facile blending method, which showed a potential application in flexible lightings and LCD displays. [ABSTRACT FROM AUTHOR]

Six acrylamide resins, derived from l‐phenylalanine and l‐leucine, are designed for application in digital light processing (DLP) printers to obtain biodegradable thermoset polymers. The acrylamide copolymers are prepared under light irradiation at 405 nm and thermal post‐curing processes. Low molecular weight poly(ethylene glycol)diacrylate (PEGDA) and N,N‐dimethylacrylamide (DMAM), both liquid resins, are used as co‐monomers and diluents for the amino acid‐derived acrylamide solubilization. The presence of two phenylalanine units and two ester groups in the acrylamide monomer accuses a fast degradation rate in hydrolytic medium in 90 days. The residual products leached in the aqueous media prove to be non‐cytotoxic, when 3D‐printed samples are cultured with osteoblast cells (MG63), which represents an advantage for the safe disposal of printer waste materials. The scaled‐up pieces derived from l‐phenylalanine and diethylene glycol, as amino acid‐derived acrylamide (named compound C), PEGDA and DMAM, present high dimensional stability after DLP printing of complex structures used as testing samples. Layers of 50 µm of thickness are well cohesive having isotropic behavior, as demonstrated with tensile‐strain measurements performed in X–Y–Z (plane) directions. The compound C, which contains phenylalanine amino acid, reveals a promising potential to replace non‐biodegradable acrylate polymers used in prototyping systems. [ABSTRACT FROM AUTHOR]

In order to explore effective strategies to fabricate main‐chain polybenzoxazine (PBZ) thermosetting resin for structural material applications, here, five PBZ with different molecular structures, that is, poly(Co‐ddm), poly(Co‐BPA‐ddm‐Co)main, poly(Ph‐BPA‐ddm‐Co)main, poly(Ph‐BPA‐ddm‐Ph)main and poly(Ph‐ddm) were designed, synthesized and compared by introducing unsaturated fatty chains through the Mannich reaction with cardanol. The structure and properties of five PBZ with different structure were systematically investigated by using Fourier transform infrared (FTIR), NMR, water absorption and mechanical tests. FTIR and NMR tests indicated that five PBZ with different molecular structures were successfully synthesized. The mechanical tests indicated that the impact strength of the double‐capped cardanol‐based main‐chain PBZ was 243% higher than that of the traditional PBZ. The water absorption of main‐chain PBZ was higher than that of diamine PBZ, and the water absorption of poly(Ph‐BPA‐ddm‐Co)main was the lowest in the main‐chain PBZ. Based on the experimental results, five PBZ amorphous cells with different structures were successfully established. It indicated that the main chain PBZ showed better thermomechanical properties than the traditional diamine PBZ due to high crosslinking conversion and hydrogen bond density. Moreover, the modulus and glass transition temperature of the main chain structure containing unsaturated fatty chains did not decrease significantly. [ABSTRACT FROM AUTHOR]

To what extent do ministries dominate a particular policy domain? The policy dictator model and many principle‐agent models of governmental control that followed suit assume that governments create ministries with clear and exclusive policy responsibilities. We test this assertion using data from parliamentary bills from Denmark, Germany, and the Netherlands. For each bill, we observe its substantial policy content and the responsible ministry. The data show that bills on similar issues regularly are drafted by different ministries in parliamentary democracies. About 40 per cent of policy issues cannot be ascribed to one dominant ministry. The regularities elucidate that ministerial division of labour within governments is considerably more complex than commonly assumed. The variegated level of ministerial dominance across policy domains calls for a new research agenda on how governments assign responsibility for legislative action in parliamentary democracies. [ABSTRACT FROM AUTHOR]

Risk expertise is characterised by procedures that emphasise scientific and technical aspects of risk management and downplay citizens' concerns and lay knowledge. In this paper, we aim at accounting for some of the reasons why technocracy is persistent in industrial risk expertise. Using the conceptual tools provided by the political sociology of expertise and based on empirical research conducted with mixed qualitative techniques, we study different types of expertise about industrial risk in the petrochemical area of Porto Marghera (Venice, Italy). The first one is performed by the Agenzia Regionale per la Protezione Ambientale del Veneto (ARPAV, Regional Agency of Veneto for Environmental Protection), which is responsible for chemical risk management, and the plants of the area. The second one is performed by the Assemblea permanente contro il pericolo chimico (APCPC, Permanent Assembly Against Industrial Risk), a citizens' association of the neighbouring community of Marghera. In this case study, we show that technocratic procedures are persistent in industrial risk due to strategic relationships between the public administration in charge of risk regulation enforcement and private chemical companies, the absence of Italian laws on inclusive participatory arenas about industrial risk, and the characteristics of the citizens' mobilisation, which focuses on plants' delocalisation rather than challenging the ARPAV's and plants' technocracy. [ABSTRACT FROM AUTHOR]

In this work, a series of multi‐component intumescent PBS formulations were elaborated by the combination of intumescent flame retardant (IFR) system (consisting of ethylenediamine phosphate and melamine poly(aluminum phosphate), 7:3, wt:wt) and synergists. Three boron/zinc‐containing compounds (i.e., melamine borate, zinc oxide, zinc carbonate) were examined as potential synergists to improve the fire behavior and fire retardancy of PBS. The MLC results showed that the incorporation of all of these compounds enhanced the fire retardancy of PBS to some extent. Among them, zinc oxide exhibited the best fire retardant performances in terms of reduction of the peak heat release rate (pHRR, −61%), fire growth rate index (FIGRA, −19%), maximum average rate of heat emission (MARHE, −55%), and increase of the time to pHRR (+370 s) and to flameout (+650 s) as compared to PBS/IFR10%. Furthermore, the effect of zinc oxide loading on the fire retardancy of PBS was also investigated, the results showed that 2 wt.% loading exhibited the best performances. Solid‐state NMR characterization indicated that the presence of ZnO resulted in the formation of a crack‐free and dense intumescent char layer reinforced by complex aluminum‐zinc‐phosphates glassy species. The intumescent char layer provided a protective physical barrier with improved flexibility and cohesion, which effectively limits the heat and mass transfer between condensed and gas phases and hence, improving the fire retardancy of PBS. [ABSTRACT FROM AUTHOR]

A silane coupling agent was used to modify the surface of expanded graphite (EG), which was subsequently used as a thermally conductive filler to fabricate diglycidylether of bisphenol‐A (DGEBA)/EG composites with high thermal conductivity via hot blending and compression‐curing processes. The surface characteristics of silane coupling agent‐modified EG (Si@EG) were characterized by a variety of analytical techniques. The effects of the Si@EG content on the thermal conductivity, thermal stability, impact strength, and morphology of the DGEBA/Si@EG composites were investigated. The results revealed that the addition of 80 wt.% Si@EG increased the thermal conductivity of the composites from 0.17 to 10.56 W/m K, which was 61.1 times higher than that of pristine DGEBA. The initial decomposition temperature of the composite containing 80 wt.% Si@EG was 60.6°C higher than that of pristine DGEBA. The impact strength of the composites decreased from 2.0 to 0.87 kJ/m2 when the Si@EG content increased from 0 to 80 wt.%. The scanning electron microscopy images of the fractured surfaces revealed that the EG sheets in the DGEBA matrix formed a continuous thermally conductive path at high Si@EG contents. [ABSTRACT FROM AUTHOR]

Polyimide (PI) composite films with hybrid fillers containing hBN (hexagonal boron nitride) sheets and rGO (reduced graphene oxide) were successfully fabricated by in‐situ polymerization. Herein, hBN sheets and rGO were obtained by ball milling and chemical reduction, respectively. In PI composite films, hBN can be tightly attached onto the surface of rGO via π‐π interaction, which can benefit the construction of heat‐conduction pathways and reduce boundary of heat resistance. The results show that the addition of rGO and hBN could enhance the thermal conductivity by synergistic effects. Specially, hBN and rGO are at the weight ratio of 1:1 and at the total loading of 33 wt%, thermal conductivity of PI composites can reach up to 1.19 Wm−1 K−1, which is 5.61 times higher than that of pure PI. Thermal property and dynamic mechanical property of composite films were also investigated. Besides, compared with pure PI, mixed fillers have obvious surface‐enhanced Raman scattering signals, indicating the synergistic effect of the mixed fillers. Overall, this study gives insights into heat dissipative and high sensitivity analysis components which may be used in the field of high‐temperature micro fabrication. [ABSTRACT FROM AUTHOR]

Benzoxazines have been widely used in many fields, such as the aerospace, electronics, and automotive industries; however, these resins exhibit nonrecyclable nature and limited strength (for their brittleness). Introducing reversible covalent bonds in benzoxazines is expected to address these issues. Herein, two‐benzene‐ring‐conjugated Schiff‐base benzoxazine was successfully synthesized using a designed strategy. Using this strategy, possible side reactions, such as the transimination of the Schiff‐base, were prevented when preparing the target product via the traditional Mannich reaction. The cured benzoxazine could chemically degrade under acidic conditions and it undergoes controllable degradation when the temperature, acidity, and solvent are changed. The synthesized benzoxazine forms noticeable liquid crystals when heated to its melting point. Its glass transition temperature also reaches 265°C and the char yield at 800°C is 60.8%, considerably higher than that of traditional bisphenol A‐aniline based benzoxazine (BA‐a). Upon blending with epoxy (EP), the mechanical properties of the copolymers are significantly improved. With increasing benzoxazine content, the tensile strength of the copolymers increases from 63.6 to 95.2 MPa, an increase of ~50%. The rigid Schiff‐base structure is uniformly incorporated into the crosslinked network of EP and the EP curing agent via a transimination reaction during curing, thereby significantly improving the tensile modulus and strength of the composite material. [ABSTRACT FROM AUTHOR]

Until recently, food packaging has been used as a barrier to unfavorable environmental and microbial conditions, but new technologies are arising aimed at upgrading the protective nature of these materials. Cases of bacterial and viral transmission through food and surfaces have shown the vulnerabilities of the food packaging distribution systems over the years, creating awareness about new methods to prevent the proliferation of pathogens. This has been highlighted by safety concerns due to the COVID‐19 pandemic. This work reviews the state‐of‐the‐art biobased technologies tailored for antiviral applications on surfaces, focusing on packaging materials. A survey and selection tool of essential oils (EOs) and nanoparticles that have been proven effective in reducing the proliferation or transmission of viruses through surfaces is presented. Additionally, the use of essential oil formulations or nanoparticle‐functionalized biobased materials that can be deployed to prevent virus transmission through food produce and surfaces is reviewed, including environmental and safety concerns around the use of metal nanoparticles and EOs in packaging materials. Finally, an assessment of the available technologies, challenges, opportunities and the potential role of biobased antiviral surfaces in future viral outbreaks is presented. [ABSTRACT FROM AUTHOR]

Polyurethane, as a rubber material, can relieve the load on the ground and provide seismic design for the venue, which is of great significance for sports venues. In order to improve the seismic resistance and abrasion resistance of materials for sports fields and reduce accidents in sports, this article has carried out research on the polyurethane elastomer layered nanocomposites for sports fields and their preparation. Today's world is a challenging era of science and technology. The fields of biotechnology, information, medicine, energy, environment, and national defense and security are closely related to the development of high tech, and the requirements for materials are becoming increasingly diversified. Polymer nanocomposite coating has the dual characteristics of organic and inorganic components. It not only retains the advantages of a polymer but also endows it with versatility. It meets the current application needs. It is a hot spot in today's research. Among them, there are two major problems in the composite process of nanomaterials and polymers: dispersion and compatibility. How to improve the dispersion of nanoparticles and enhance the compatibility between nanoparticles and polymers is an urgent problem to be solved. In the method part, this article introduces a small amount of polyurethane and polyurethane elastomers formed after polyurethane modification and introduces layered compounds and nanocomposites and introduces several models involved in nanomaterials in terms of algorithms. In the analysis part, this paper conducts a comprehensive analysis of the hard segment mass fraction, mechanical properties, thermal decomposition behavior, degradation mechanism, and dynamic mechanical properties. With the increase of GO content, the tensile strength increases significantly and the elongation at break becomes smaller and smaller. When the GO content increases from 0% to 2%, the tensile properties of the WPU film increase from 2.6 MPa to 7.9 MPa and the fracture of the elongation decreased from 201.7% to 62.8%. This shows that the increase in GO content will make the composite material harder and brittle. It can be seen from the experimental results that the preparation of the polyurethane elastomer layered nanocomposite material designed in this paper has a good application effect on sports venues. [ABSTRACT FROM AUTHOR]

Cyclosiloxanes possessing organic functional moieties are reactive organic–inorganic hybrids as effective building blocks for preparation of organic–inorganic nanocomposites. In this work, a tetra‐functional benzoxazine compound (cD4‐4Bz) with a cyclosiloxane core has been synthesized, cD4‐4Bz could be considered as a self‐crosslinkable benzoxazine compound and has been utilize in preparation of the corresponding polybenzoxazine‐cyclosiloxane thermosetting resins. The obtained crosslinked polybenzoxazines exhibit good film formability and attractive thermal properties including a thermal stability above 390°C, a glass transition temperature above 400°C, and a char yield of 64.5 wt% at 800°C, and low dielectric constant of 2.74 and a dissipation factor of 0.18 at 10 GHz. The hig char yield also indicates its high flame retardancy with a calculated limited oxygen index of 44. Moreover, cD4‐4Bz is a suitable agent for polymer modification through cocuring reactions with a tetrafunctional cyclosiloxane‐phenol compound, a main‐chain benzoxazine, and a bifunctional benzoxazine compound. One prepared sample has exhibited a high thermal stability above 435°C and a char yield of 72.9 wt%. The high flexibility and variety in the fabrication of high‐performance thermosetting resin have been demonstrated. [ABSTRACT FROM AUTHOR]

BACKGROUND: Membrane technology has attracted increasing interest in the field of separation and purification. Unfortunately, conventional membrane materials are usually derived from non‐renewable fossil resources that are difficult to degrade at the end of their life. In this work, as a sustainable alternative to the conventional polymer membrane, the biobased ploy (L‐lactic acid) (PLLA) hybrid membrane was successfully fabricated through the incorporation of modified natural halloysite nanotubes (HNTs). RESULTS: The PLLA/HNT hybrid membranes were analysed by attenuated total reflectance‐Fourier transform infrared spectroscopy (ATR‐FTIR), X‐ray diffraction (XRD), scanning electron microscopy (SEM), X‐ray diffraction (XRD), and contact angle measurement. The pure water flux of the hybrid membrane increased from 140.3 to 329.7 L.m−3.h−1, while the bovine serum albumin (BSA) rejection ratio decreased from 94.3 to 82.7% with increasing HNT loading content from 0 to 1 wt%. Moreover, the addition of HNTs could also enhance the antifouling performance of the hybrid membrane. CONCLUSION: The green PLLA/HNT hybrid membrane was successfully made from the recoverable and biodegradable PLLA and naturally occurring HNTs. Compared with the PLLA‐based membranes reported in the literature, the PLLA/HNT hybrid membranes presented relatively high permeability, moderate BSA rejection, and good antifouling performance. The green poly (L‐lactic acid) hybrid membranes hold great promise for practical application as they can contribute to a circular economy and sustainable development. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Catecholaminergic neurons are abundant in molluscs and are involved in a variety of behaviors such as feeding, respiration, learning, and locomotion. However, previous identification of these neurons has relied almost exclusively on immunohistochemistry using antibodies, which have not been fully validated for use in molluscs. We employed tissue‐specific quantitative PCR in adults of Lymnaea stagnalis (a pulmonate gastropod) and whole‐mount in situ hybridization in larvae to both quantify and visualize messenger RNA of the catecholamine synthesis enzyme, tyrosine hydroxylase (TH). TH messenger RNA was found to localize primarily in the foot and the central nervous system, with smaller quantities present in the cephalic sensory organs. Additionally, we performed western blots that validated a popular antibody used as a marker for catecholaminergic neurons in molluscs. Taken together, these data indicate that TH messenger RNA is present in the central and peripheral nervous system of L. stagnalis and support the specificity of past immunohistochemical labeling of the TH protein. These findings have potentially broad implications, given the wide range of biological processes that have been studied in L. stagnalis. [ABSTRACT FROM AUTHOR]

In this work, electro‐responsive shape‐memory actuators were developed by incorporating a conductive heater in a dual‐curing thiol‐acrylate‐epoxy shape‐memory polymer (SMP). A conductive heater, consisting of an electrically conductive silver‐ink track printed on Kapton® substrate, was assembled to the SMP, taking advantage of the dual‐curing processing. The shape‐memory effect (SME) was activated by the heat dissipated by the Joule effect in the conductive track. Boron nitride agglomerates were dispersed in the thiol‐acrylate‐epoxy layers to increase thermal conductivity and achieve faster shape‐recovery. A thermoelectric control unit was developed to control the shape recovery of the electro‐responsive actuators and provide different activation strategies. The electrically activated SME was investigated and compared to a traditional SME based on an external heating source given by the dynamic mechanical analyzer (DMA) apparatus. Electro‐responsive actuators were found extremely faster than the conventional SMPs based on external heating. The fastest recovery was obtained by the 15% boron nitride actuator, which recovered the 100% of the original shape in only 8 s. The thermoelectric controlling device provided an optimal control of the shape recovery speed based on the pulse width modulation of the heating current under the application of a low voltage (5 V). [ABSTRACT FROM AUTHOR]

In this study, a phosphorous‐containing benzoxazine was synthesized using a bio‐based primary amine, vanillin diamine true sample 2 (VDTS2, IUPAC name: 4‐(([3‐aminopropyl] imino) methyl)‐2‐methoxyphenyl(4‐(([3‐aminopropyl] imino) methyl)‐2‐methoxyphenyl) phenylphosphonate), paraformaldehyde and vanillin and tested for its use as a flame‐retardant. The molecular structure of the synthesized benzoxazines was characterized by FTIR spectroscopy and 1H NMR spectroscopy. Polybenzoxazine was obtained through the ring‐opening polymerization of the benzoxazine monomer, and the formation of the same was confirmed through FTIR spectroscopy. The polymerization mechanism of the benzoxazine was investigated using thermogravimetric analysis (TGA). The thermal properties of the benzoxazine were studied using differential scanning calorimetry and TGA. The flame‐retardant properties of the polybenzoxazine films obtained were investigated by the LOI. Due to the highly brittle nature of the polybenzoxazine, the synthesized polybenzoxazine was further crushed and incorporated into an epoxy system to investigate its use as a flame‐retardant additive. The thermal property and flame‐retardant property of the epoxy films were then studied. The flame‐retardant and thermal stability test results of the epoxy‐pbz films showed that the epoxy‐pbz films showed improved thermal stability and achieved a UL‐94 V‐0 rating and an LOI of 28% at 15% by weight of the polybenzoxazine concentration. SEM analysis was also conducted to study the surface morphology of the polybenzoxazine and epoxy‐pbz films pre and post the flame test. FTIR analysis was carried out to study the flame retardant mechanism of the polybenzoxazine and the epoxy‐pbz film. The respective films' mechanical properties were also investigated to study the film‐forming capability of the films. [ABSTRACT FROM AUTHOR]

Summary: Flame‐retarded sorbitol‐based bioepoxy resins cured with cycloaliphatic amine hardener and containing different commercially available additive‐type flame retardants (FRs) have been prepared. Three different oxidation states of phosphorus, aluminium diethyl phosphinate (AlPi) (+1), phosphonate polyol (+3), ethyl ethylene glycol phosphate and ammonium polyphosphate (APP) (+5), have been studied. The effect of using melamine cyanurate with APP and AlPi has been assessed. The self‐extinguishing V‐0 rating according to UL‐94 flammability standard tests and very good limiting oxygen index for combustion are displayed for most flame‐retarded samples at 3 wt% phosphorus content. The flame retardancy effect for the additives was confirmed using cone calorimetry. The samples containing MC with APP at 3%P content showed a dramatic reduction of the total heat release by 60% and reduction of the peak of heat release rate by 70% compared to the reference epoxy matrix. The addition of these FRs together did not decrease the glass transition temperature significantly. [ABSTRACT FROM AUTHOR]

The wide application range and ascending demand for platinum group metals combined with the progressive depletion of their natural resources renders their efficient recycling a very important and pressing matter. Primarily environmental considerations associated with state‐of‐the‐art recovery processes have shifted the focus of the scientific community toward the investigation of alternative recycling approaches. Within this context, ionic liquids have gained considerable attention in the last two decades chiefly sparked by properties such as tunabilty, low‐volatility, and relatively easy recyclability. In this review an understanding of the state‐of‐the‐art processes, including their drawbacks and limitations, is provided. The core of the discussion is focused on platinum group metal recovery with ionic liquid‐based systems. A brief insight in some environmental considerations related to ionic liquids is also provided while some discussion on research gaps, common misconceptions related to ionic liquids and outlook on unresolved issues could not be absent from this review. [ABSTRACT FROM AUTHOR]

Recycled polymeric materials recovered from E‐waste, have gained importance in the recent years, due to the value addition of properties in the recycled materials. In the current work, a polymeric blends formulated from keyboard waste plastics was value added using a flame retardant (FR), and these plastics are not incorporated with FR during its processing. This work was carried out to enhance the FR property of polymers recovered from keyboard waste, and to study the effects of these additives on the mechanical properties of the polymeric blends. The FR tri phenyl phosphate (TPP), and a hybrid FR combining TPP with sepiolite, was added in different proportions to the blend. The FR blends were analyzed with UL‐94 and LOI and it was observed that the blends with hybrid FR showed higher FR properties, as the results of UL‐94 and LOI showed V‐1 and 29%, respectively. The cone calorimetry results showed that the peak heat release rate of the blends was improved from 704 to 533 KJ/m2. The gas and condensed phase reaction has been explained with an illustration. FTIR and TGA with and without the FR were performed. The mechanical properties of the blends drastically reduced after the addition of FRs, hence an impact modifier was added in order to regain the lost mechanical properties, and a morphological analysis was carried out to compare the influence of impact modifier in the polymeric blend. [ABSTRACT FROM AUTHOR]

Ocean deoxygenation events are intensifying worldwide and can rapidly drive adult corals into a state of metabolic crisis and bleaching‐induced mortality, but whether coral larvae are subject to similar stress remains untested. We experimentally exposed apo‐symbiotic coral larvae of Acropora selago to deoxygenation stress with subsequent reoxygenation aligned to their night‐day light cycle, and followed their gene expression using RNA‐Seq. After 12 h of deoxygenation stress (~2 mg O2/L), coral planulae demonstrated a low expression of HIF‐targeted hypoxia response genes concomitant with a significantly high expression of PHD2 (a promoter of HIFα proteasomal degradation), similar to corresponding adult corals. Despite exhibiting a consistent swimming phenotype compared to control samples, the differential gene expression observed in planulae exposed to deoxygenation‐reoxygenation suggests a disruption of pathways involved in developmental regulation, mitochondrial activity, lipid metabolism, and O2‐sensitive epigenetic regulators. Importantly, we found that treated larvae exhibited a disruption in the expression of conserved HIF‐targeted developmental regulators, for example, Homeobox (HOX) genes, corroborating how changes in external oxygen levels can affect animal development. We discuss how the observed deoxygenation responses may be indicative of a possible acclimation response or alternatively may imply negative latent impacts for coral larval fitness. [ABSTRACT FROM AUTHOR]

The nautilus, commonly known as a "living fossil," is endangered and may be at risk of extinction. The lack of genomic information hinders a thorough understanding of its biology and evolution, which can shed light on the conservation of this endangered species. Here, we report the first high‐quality chromosome‐level genome assembly of Nautiluspompilius. The assembled genome size comprised 785.15 Mb. Comparative genomic analyses indicated that transposable elements (TEs) and large‐scale genome reorganizations may have driven lineage‐specific evolution in the cephalopods. Remarkably, evolving conserved genes and recent TE insertion activities were identified in N. pompilius, and we speculate that these findings reflect the strong adaptability and long‐term survival of the nautilus. We also identified gene families that are potentially responsible for specific adaptation and evolution events. Our study provides unprecedented insights into the specialized biology and evolution of N. pompilius, and the results serve as an important resource for future conservation genomics of the nautilus and closely related species. see also the Perspective by Gustavo Sanchez, Oleg Simakov and Daniel S. Rokhsar. [ABSTRACT FROM AUTHOR]

This article advances scholarship on comparative regulation by moving beyond the conventional focus on formal law and EU comitology to assess the extent of 'practice convergence' in the implementation of EU regulation. Drawing on 50 key informant interviews, a survey, and policy document analysis, we compare how regulators in England, Germany, France and the Netherlands have implemented EU requirements that food safety inspections be 'risk‐based'. Focusing on a clear dependent variable – risk‐scoring methods – we find important differences in the conception and targeting of risk‐based inspections; with starkly different implications for what kind of food businesses they need to target to ensure safety within an ostensibly harmonized single market. We attribute variation in the implementation of risk‐based inspection to the ways that EU requirements were filtered through long‐entrenched regulatory styles and modes of food business organization in each country, reinforcing preexisting inspection practices in the design of new risk‐based tools. [ABSTRACT FROM AUTHOR]

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High loadings of fillers are usually needed to achieve high‐thermal conductivity (TC) of polymer‐based composites, which inevitably sacrifices processability and meanwhile causes high‐cost. Therefore, it is of great significance to achieve high‐TC composites under low‐filler loading. Here, a novel p‐phenylenediamine (PPD) modified expanded graphite (EG‐PPD)/epoxy (EP) composite with high TC and low‐filler content was successfully prepared via pre‐dispersion and vacuum assisted mixing strategy. With the improved interfacial compatibility between EG and EP by PPD, the prepared EG‐PPD/EP composite exhibited excellent thermal management performance, resulting in the TC of which reached 4.00 W·m−1·K−1 with only 10 wt% (5.59 vol%) of EG‐PPD, which is approximately 19 times higher than that of pure EP. Meantime, the interface thermal resistance of EG‐PPD/EP composite between EG‐PPD and EP is reduced by 33% compared with EG/EP composite. This composite with excellent TC property is expected to be used in thermal management field. [ABSTRACT FROM AUTHOR]

We report the toughness improvement of epoxy thermosets by the use of cellulose nanocrystals (CNCs). Pristine CNCs were functionalized via surface‐initiated reversible addition–fragmentation chain transfer/macromolecular design via interchange of xanthates (RAFT/MADIX) polymerization. The pristine CNCs were first surface‐treated with 4‐cyano‐4‐(isopropoxycarbonothioylthio)pentanoic chloride and then poly(N‐vinylpyrrolidone)‐grafted CNCs (CNC‐PVPy) were synthesized with the xanthate‐functionalized CNCs as chain transfer agent. Notably, the as‐obtained CNC‐PVPy can be dispersed into epoxy thermosets in the form of single fibrous nano‐objects, i.e. the nanocomposites of epoxy with CNCs were successfully obtained. The uniform dispersion of CNCs in epoxy matrix is attributable to the compatibilizing effect of PVPy chains. The introduction of CNCs markedly improved the toughness of epoxy thermosets. When the mass fraction of CNC‐PVPy was 30 wt%, the nanocomposites displayed the maximum critical stress intensity factor (K1C) and critical fracture energy (G1C) of 1.76 MN m−3/2 and 0.66 kJ m−2, respectively. The toughening of epoxy thermosets is mainly attributed to the plastic deformation of epoxy matrix, which is initiated from CNCs. © 2021 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Nature is blessed with self-healing properties. Mimicking nature is a traditional practice to innovate new classes of materials for researchers. In this practice, researchers made a revolutionary approach to innovate self-healing polymer (SHP) that can be used to treat damage-related losses. Different SHPs with various properties have been developed for a wide range of applications. SHPs unlocked the key to the taste of real life through their application and versatility in the sectors close to our day-by-day life of this age and the near future. In this study, we reviewed the scopes and prospects of the application of SHPs owing to different properties. Varieties of amazing properties made SHPs fit in different sectors such as construction, paint and coat, electronics, healthcare, textile, and automotive and aerospace. Similarly, due to having suitable functionality, SHPs can also be used in different industries. Therefore, it is high time to generalize the production of SHPs by suitable research and make sure the easy application for the welfare of human civilization and other living creatures. [ABSTRACT FROM AUTHOR]

The effect of silylation of microfibrillated cellulose (MFC) surfaces on β‐phase formation in poly(vinylidene difluoride) (PVDF) and the resulting viscoelastic and dielectric performance of MFC‐PVDF composites is investigated. Two different organosilanes, namely aminated (A) and fluorinated (F), were used. Composites of PVDF and MFC at concentrations up to 10 wt%, both untreated and silylated, were prepared by solvent casting. The two different surface modifications did not markedly change the melting and crystallization enthalpy of the polymer. However, only A‐MFC was found to promote β‐phase compared to the untreated MFC and the F‐MFC, which was attributed to the formation of hydrogen bonds at the interface between the amine groups of A‐MFC and the fluorine groups of PVDF. The elastic modulus and the permittivity of all composites increased with the amount of MFC up to a maximum value, depending on the MFC modification, and then decreased. This effect was due to the formation of MFC aggregates and porosity, as further confirmed by a comparison of experimental moduli with a classical composite mechanical model. The highest elastic modulus and highest permittivity were obtained for the untreated MFC and A‐MFC composites with 5 and 1 wt%. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Linear low-density polyethylene (LLDPE), biaxially oriented polypropylene (BOPP), polyethylene terephthalate (PET) and Nylon 6 films used for food packaging application were subjected to e-beam (EB) irradiation at different doses in the range of 0 to 80 kGy. The mechanical, barrier, optical and thermal properties of the irradiated films were evaluated and compared with the non-irradiated films. A notable decrease in oxygen transmission rate (OTR) was observed for BOPP and Nylon 6 specimens after irradiation, whereas for PET samples, no significant change was noticed. Water vapour transmission rate (WVTR) was found to exhibit a decreasing trend for PET and Nylon 6 samples but remains unchanged for BOPP after EB irradiation. Tensile strength (TS) of Nylon 6 and LLDPE films was found to increase upon irradiation up to 20 kGy, whereas for BOPP, a clear decreasing trend was observed. No significant change in TS and elongation at break was observed for PET film after irradiation. The melting temperature (Tm) and enthalpy of melting (ΔHm) were decreased with EB dose as revealed by differential scanning calorimetry (DSC) studies. [ABSTRACT FROM AUTHOR]