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Poly(lactic acid) fiberwebs and multi‐ply assemblies of nettle woven reinforcement are used to develop a series of nettle/PLA biocomposites with different reinforcement orientations. The tensile strength, flexural strength, impact strength, and thermal properties of the biocomposites are found to improve by piling nettle fabrics and are also found to depend strongly on the piling architecture and the test direction. It is possible to obtain a biocomposite with higher degrees of isotropy and enhanced mechanical properties by using cross‐ply laminates. The three‐layered woven fabric reinforced PLA biocomposite with a reinforcement orientation 0°/45°/90° shows the best results among all the biocomposites developed in this study. The tensile strength, Young's (tensile) modulus, flexural strength, impact strength, storage modulus, and loss modulus of the biocomposite are found as 55.25 MPa, 6.30 GPa, 85.83 MPa, 63.74 J/m2, 10.08 GPa, and 0.75 GPa, respectively. In this biocomposite, a fair adhesion between matrix and reinforcement is noticed, and this is justified by retardation of crack propagation as well as by substantial energy dissipation. The thermal stability of the biocomposite does not get effected much, but the percent crystallinity increases by 25.84%. The degradation kinetics and the activation energy of the biocomposite are determined through a differential fitting of Arrhenius model. The soil burial test reveals 15.06% of weight loss and 50.56% strength loss for this biocomposite just after 20 days of burial under soil. Highlights: Multi‐ply architecture of woven fabric reinforcement in nettle/PLA biocomposites.Nearly isotropic biocomposite through angle‐ply orientation of reinforcement.Biocomposite with remarkable static and dynamic mechanical properties.Augmented kinetic parameters through model fitting of Arrhenius equation.Biocomposite with excellent thermo‐recyclability and biodegradability. [ABSTRACT FROM AUTHOR]

Summary: In frozen part‐baked bread technology, starch is influenced by various processing factors. This study aimed to investigate the effect of part‐baking time, freezing rate and frozen storage time on pasting, thermal and structural properties of part‐baked bread. Wheat dough was part‐baked for 0, 3 or 6 min and frozen at −20 °C using two freezing rates: slow (0.15 °C min−1) or fast (1.45 °C min−1). Next, samples were stored in frozen conditions for 56 days and analysed every 14 days for starch damage, pasting properties, thermal and X‐ray analysis. The level of damaged starch increased with 3 min (69.3%), and 6 min (88.8%) of part‐baking time for both freezing rates compared to no part‐baked. In pasting analyses, peak viscosity decreased 27.3% and 38.4% for 3 and 6 min of part‐baking time, respectively, at 0 days of frozen storage; however, this tendency was observed for all frozen storage time. The gelatinisation enthalpy (ΔHg) decreased as part‐baking time increased, showing the maximum reduction at 6 min of part‐baked (94.9%). In X‐ray diffraction analyses at 3 and 6 min of part‐baking, the intensity of the signal increased 4.4% and 10.9%, respectively, probably due to the starch gelatinisation. These results can serve as a valuable guide for developing strategies to enhance the quality of part‐baked bread and improve production performance. [ABSTRACT FROM AUTHOR]

1,3,5‐trinitroso‐1,3,5‐triazine (R‐Salt) is an insensitive energetic that has previously been used as an improvised explosive. The work presented here is a comprehensive study on the thermal properties and chemical characterization of R‐Salt. Thermal analysis was performed via differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) which found both crude and recrystallized R‐Salt have similar thermal properties but the selected lid impacted both the thermal profile and onset temperature. Chemical characterization performed via Raman, Fourier‐transform Infrared (FT‐IR), nuclear magnetic resonance (NMR) spectroscopy and high‐resolution mass spectrometry indicate that recrystallization does not quantitatively improve the purity of crude R‐Salt., The reported NMR 2D‐HSQC, FT‐IR, and Raman spectra are the first to be reported within the published literature, as to the authors' knowledge. [ABSTRACT FROM AUTHOR]

In this work, we have synthesized the zinc‐aluminum layered double hydroxide (ZnAl LDH) nanostructures using cost‐effective hydrothermal technique. The ZnAl LDH and graphene‐based poly(vinyl alcohol) (PVA) nanocomposites are fabricated. The crystal structure, morphology, thermal, and dielectric properties of pristine PVA and ZnAl LDH and graphene‐based PVA nanocomposites films were investigated using X‐ray diffraction, HR‐transmission electron microscopy, thermo gravimetric analysis, and impedance analyzer. HRTEM analysis reveals the hexagonal nanoplates shape‐like morphology of Zn‐Al layered double hydroxides with an average thickness of 40–50 nm and size of 400–600 nm. High thermal stability was observed from ZnAl LDH and graphene‐reinforced nanocomposite. Enhanced thermal stability of 250°C and low weight loss was observed from ZnAl LDH reinforced PVA‐based nanocomposites compared to pristine PVA. Zn‐Al LDH nanoplates‐graphene‐PVA based nanocomposites showed ultra‐high dielectric constant (ɛ′) of 794 as compared to the ZnAl LDH‐PVA nanocomposites (ɛ′ ~ 334) and pristine PVA sample (ɛ′ ~ 35). Low dielectric loss of 0.27, 0.18, 0.38 was observed for pristine PVA, ZnAl‐LDH‐PVA and ZnAl‐LDH‐graphene‐PVA nanocomposites. The large enhancement of the dielectric constant and thermal stability were discussed in terms of improved crystallinity, interfacial polarization and formation of nanodipoles in the matrix. This study reveals a significant role of LDH‐graphene‐based hybrid nanocomposites in optoelectronics, energy storage, sensors, energy conversion and thermally stable devices. Highlights: Growth of highly crystalline zinc‐aluminum layered double hydroxide nanostructures.Improved thermal stability for Zn‐Al LDH‐graphene‐PVA nanocomposites.High thermal stability from ZnAl LDH‐based PVA nanocomposites.Ultra‐high dielectric constant of 794 is observed from Zn‐Al LDH nanoplates‐graphene‐nanocomposites. [ABSTRACT FROM AUTHOR]

Prototype development nowadays can rarely be imagined without 3D printing. In the fast‐moving electronics industry, 3D printing is a good way to react quickly to changing developments, for example, when it comes to heat sinks made of thermally conductive material. 3D printing of thermally conducting plastics, which are also electrically insulating, is an ideal candidate for the rapid generation of heat sink. Nevertheless, 3D printing also shows some drawbacks in regard to properties of the printed parts, as porosities or layer adhesion, emerging from layer deposition in the process. Therefore, the aim of this work was to investigate the influence of the orientation of fillers on the thermal conductivity of filled polylactic acid (PLA). PLA was filled with amounts of 15–45 wt.% of boron nitride and aluminum granules and printed into heat sinks in two different orientations to investigate this influence on the thermal conductivity. The printed heat sinks were then placed on a heated aluminum block and the thermal transport was examined with an infrared camera. It could be shown that especially with platelet‐shaped fillers such as boron nitride, the orientation of these in the test specimen has a large influence on the thermal conductivity. Highlights: 3D printing of thermally conductive heat sinksThermal characterization of 3D printed heat sinksComputer tomography scans of heat sinks to evaluate the porosity [ABSTRACT FROM AUTHOR]

Nowadays, various types of biocomposites are being developed using different types of natural fibers and polymers to fulfill the requirement for sustainable products. Recently, the addition of fillers in biocomposites has been a useful approach to improve their performance and overwhelm their limitations. The hollow glass microspheres (HGMs) were uniformly distributed into epoxy using a magnetic stirrer and subsequently, a hand lay‐up technique was employed to produce the HGMs/coir/epoxy composites under a static loading condition. In the current study, the effect of varying weight percentages (i.e., 1, 3, and 5) of HGMs on the mechanical, dynamic mechanical, and thermal properties of coir/epoxy composites has been studied. Further, morphological analysis of fractured surfaces of samples was also performed. The results suggested that the addition of HGMs caused a significant improvement in the tensile and impact properties of the composites but could not extensively improve the flexural strength, thermal stability, storage modulus, and loss modulus. There was a significant improvement of 80.5% in tensile strength and 24.7% in impact strength of composites after the addition of 1 wt%. HGMs. Further, tensile and flexural moduli were found to be gradually improved with increased HGMs weight percentages in the composites. Highlights: Development of HGMs/coir/epoxy composites.Addition of HGMs increases tensile and impact strength of coir/epoxy composites.Microstructural analysis of HGMs/coir/epoxy composites. [ABSTRACT FROM AUTHOR]

Rheological and thermal properties are important parameters to understand the role of the numerous variables involved in manufacturing and to achieve a high‐quality final product. The composites were prepared by compounding polypropylene (PP) with treated (alkaline and silane) oil‐palm empty fruit bunch (EFB) fiber using a twin screw extruder. Generally, regardless of fiber loading, the thermal stability of EFBPP composites was increased after using alkaline and silane‐treated EFB fibers as reinforcement. DSC analysis shows that there is a change in the melting temperature (Tm) and the degree of crystallinity (Xc) values of the EFB composites. The melt flow rate (MFR) of the composites decreased while viscosity increased with an increase in fiber loading. Rheological analysis reveals the composites to have a viscoelastic solid behavior where storage modulus (G') is greater than loss modulus (G"). The composites exhibit predominantly viscous behaviour (G" > G') at lower frequencies, whereas at higher frequencies the composites exhibit elastic behavior (G' > G"). The decrement of complex viscosity (η*) with an increasing angular frequency (ω) shows the materials exhibit shear thinning behavior. The composites also show the ability for regeneration when analyzed using time‐dependent behavior. [ABSTRACT FROM AUTHOR]

Two azo dye ligands, bearing different substituents (chlorine atom or methoxy group) in the para‐position of the phenyl ring, were employed for the synthesis of two Cu(II) chelates. Full structural affirmation of complexes was assessed. X‐ray diffraction measurements revealed that the coordination geometry for Cu atoms in both complexes is square‐pyramidal with a ligand:metal ratio of 2:1 where dyes behave as monobasic bidentate ligands. Thermogravimetric analyses of the complexes and their starting dyes were performed to study their thermal stabilities and decomposition behavior confirming the thermal stability of both dyes and complexes. Antioxidative activity of the complexes has been assigned and compared with their parent ligands revealing that the presence of the electron–donor, methoxy group, in the phenyl ring, in both dye and complex, is responsible for the activity (IC50 values of 1.54 for the dye and 1.30 mM for the complex). It should be stated that the complexation of the methoxy‐substituted dye leads to enhanced antioxidative activity concurrent to a standard antioxidant molecule of ascorbic acid, making this molecule a promising antioxidant agent. Docking study with vascular endothelial growth factor receptor 2 and Aurora kinase A proteins indicate that complexes exhibit higher binding affinities to proteins than the starting ligand dyes. The most promising structure exhibiting the best docking potential toward both proteins is the complex‐bearing methoxy group. The presented results represent a promising start for further investigations of these compounds as potential therapeutic candidates for the treatment of various types of cancer. [ABSTRACT FROM AUTHOR]

Polyolefin copolymers have been an important commercial product since their invention. Hence, it is crucial to study their co‐ and terpolymers due to their extensive use. In this paper, in situ synthesis of ethylene‐propylene (EP) copolymer, its terpolymer with styrene, and composites with nickel‐chromium (NiCr) layered double hydroxide (LDH) has been reported along with their thermal properties. Styrene had a significant impact on the activity, increasing the yield by 195% and 235% with an addition of 0.5 and 1.0 mL styrene, respectively, compared to neat EP. The crystallinity, melting temperature, and thermal stability decreased due to styrene; nevertheless, it performed better compared to a similar work of terpolymer where α‐olefin was the third monomer. The incorporation of NiCr LDH as a drop‐in filler during in situ polymerization affected adversely the thermal stability of the terpolymer. However, the ultrasonication treatment improved the thermal stability of the final product. [ABSTRACT FROM AUTHOR]

Combining thermal conductivity with electrical isolation is a very interesting topic for electronic applications in order to transfer the generated heat. Typical approaches combine thermally conductive fillers with a thermoplastic matrix. The aim of this work was to investigate the influence of different fillers and matrices on the thermal conductivity of the polymer matrix composites. In this study, various inorganic fillers, including aluminum oxide (Al2O3), zinc oxide (ZnO), and boron nitride (BN) with different shapes and sizes, were used in matrix polymers, such as polyamide 6 (PA6), polypropylene (PP), polycarbonate (PC), thermoplastic polyurethane (TPU), and polysulfone (PSU), to produce thermally conductive polymer matrix composites by compounding and injection molding. Using simple mathematical models (e.g., Agari model, Lewis–Nielson model), a first attempt was made to predict thermal conductivity from constituent properties. The materials were characterized by tensile testing, density measurement, and thermal conductivity measurement. Contact angle measurements and the calculated surface energy can be used to evaluate the wetting behavior, which correlates directly with the elastic modulus. Based on the aforementioned evaluations, we found that besides the volume fraction, the particle shape in combination with the intrinsic thermal conductivity of the filler has the greatest influence on the thermal conductivity of the composite. [ABSTRACT FROM AUTHOR]

The present research is based on the thermal and flow properties of the viscoelastic Oldroyd 8 constant fluid in an upright microchannel. The energy and momentum equations were solved with the support of temperature Jump and velocity slip boundary conditions. To measure the irreversibility rate of the flow system, the acquired results of velocity and thermal equations were used. To crack the current mathematical model problem, the numerical Runge–Kutta–Fehlberg method was used. With the aid of graphs, the effect of physical parameters such as thermal radiation, thermal‐dependent heat source, Joule heating, fluid parameters, velocity slip, and temperature Jump parameters on the fluid flow, thermal energy, and system entropy generation was discussed. Fluid parameters have different effects on the velocity profile. The Grashof and Hartmann numbers demonstrate opposite effects on the momentum field. The thermal energy of the system reduces with thermal radiation and temperature Jump factor. The thermal radiation, Hartmann number, and temperature Jump parameters reduce the system's irreversibility rate. With the Brinkman number and temperature Jump parameter, the irreversibility ratio increases. [ABSTRACT FROM AUTHOR]

The present study focuses on the numerical modeling of the thermal buckling behavior of tapered laminated composite beams validated by experimentation. Lagrange's energy‐based governing differential expression was derived utilizing classical laminated plate theory and higher‐order shear deformation theory to analyze the tapered composite beam's thermal buckling property. The uniform temperature rise environment is employed to estimate the critical buckling temperature of the tapered laminated composite beam. The obtained results from the numerical approaches were validated with the experimental results and the previous results obtained from the literature associated with the fundamental frequencies of the structure and critical buckling temperature. The parametric study was incorporated in this present work to investigate the influence of the structural parameters and the geometrical parameters like taper angle, ply orientation, aspect ratio, and boundary constraints of the beam. [ABSTRACT FROM AUTHOR]

A “self-permeation” method was used to fabricate a Ca0.9La0.067TiO3-0.01Al2O3 (CLT)-reinforced polysilylaryl-enyne/fiber multilayer board with different volume fractions of CLT (0–40 vol%). The microstructure, dielectric, mechanical, and thermal properties were fully studied. The results showed that the composite with optimal dielectric properties (εr∼8.75, tanδ∼0.0043) could be obtained when the volume fraction of CLT reached 30 vol%. Meanwhile, the thermal conductivity reached a high level of 0.644 W/(m⋅K) and 0.762 W/(m⋅K) at Z and X/Y directions, respectively. Due to the high decomposition temperature of PSAE, Td5 (the temperature corresponding to 5% weight loss) of composite loading with 30 vol% CLT was higher than 900°C, which indicates an excellent thermal resistance. And the bending strength could reach 115.3 MPa indicating excellent mechanical property. The novel polysilylaryl-enyne/fiber/Ca0.9La0.067TiO3-0.01Al2O3 multilayer board with excellent performance is expected to be a candidate material for print circuit boards and widely used in the microwave communication field. [ABSTRACT FROM AUTHOR]

A “self-permeation” method was used to fabricate a Ca0.9La0.067TiO3-0.01Al2O3 (CLT)-reinforced polysilylaryl-enyne/fiber multilayer board with different volume fractions of CLT (0–40 vol%). The microstructure, dielectric, mechanical, and thermal properties were fully studied. The results showed that the composite with optimal dielectric properties (εr∼8.75, tanδ∼0.0043) could be obtained when the volume fraction of CLT reached 30 vol%. Meanwhile, the thermal conductivity reached a high level of 0.644 W/(m⋅K) and 0.762 W/(m⋅K) at Z and X/Y directions, respectively. Due to the high decomposition temperature of PSAE, Td5 (the temperature corresponding to 5% weight loss) of composite loading with 30 vol% CLT was higher than 900°C, which indicates an excellent thermal resistance. And the bending strength could reach 115.3 MPa indicating excellent mechanical property. The novel polysilylaryl-enyne/fiber/Ca0.9La0.067TiO3-0.01Al2O3 multilayer board with excellent performance is expected to be a candidate material for print circuit boards and widely used in the microwave communication field. [ABSTRACT FROM AUTHOR]

Three new ytterbium complexes of the general formula [YbL2Cl3] with expanded aromatic N‐donor based ligands based on 1,10‐phenanthroline (dipyrido‐[3,2‐f : 2′,3′‐h]‐quinoxaline (DPQ), 2‐methyldipyrido‐[3,2‐f : 2′,3′‐h]‐quinoxaline (MeDPQ) and 1,10‐phenanthroline (Phen)) were synthesized and characterized using different structural analysis, simultaneous thermal analysis, and photoluminescence, and UV‐Vis‐NIR spectroscopy. The compounds were obtained by the reaction of ytterbium(III) chloride hexahydrate and the corresponding aromatic N‐donor through substitution of water from the coordination sphere with the organic ligand. Photoluminescence studies revealed Yb3+‐based NIR emission of the corresponding compounds with following luminescence lifetimes [Yb(DPQ)2Cl3] (1) – 7.8(1) μs, [Yb(MeDPQ)2Cl3] (2) – 9.3(1) μs, [Yb(Phen)2Cl3] (3) – 8.7(1) μs. The resulting complexes are stable under atmospheric conditions, exhibit good thermal stability, and start to oxidize only at sufficiently high temperatures: (1) at 470 °C, (2) at 430 °C, and (3) at 395 °C. [ABSTRACT FROM AUTHOR]

In the present study, the influence of numerical analysis involves the transfer of heat for moving fin under convection and radiation with fluid properties depending on internal heat generation is considered. The temperature field for the fin is derived based on the defined geometry. This is transformed into a linear model as per the boundary conditions. The dimensionless analysis is performed, and the equations obtained are solved by Runge–Kutta Fehlberg fourth‐order method coupled with the shooting method. The effects of the relative parameters are studied and depicted graphically. Finally, the computational observation indicates that there is an enhancement of temperature variation under the influence of thermal conductivity gradient, heat generation, and opposite behavior results. In understanding the thermal characteristics of various effects, it was seen that thermo geometric film, radiation conduction, and Peclet number were very useful for many industrial applications. To validate the numerical scheme, a comparative study has been done with an earlier result on a few nondimensional parameters and was found in good agreement. [ABSTRACT FROM AUTHOR]

The current study focuses on treated and untreated Musa acuminate peduncles fiber (MAPFs) reinforced polyester composites for lightweight application. For the first time, the impact of alkali treatment and fiber weight fraction on the mechanical, thermal, and morphological characteristics of MAPFs bonded polyester composites have been examined. The fiber from 0 to 25 wt% (alkali‐treated and raw) was reinforced with polyester matrix in compression/hand lay method. At 20 wt% of fiber, significant improvements in tensile strength (40.97 MPa), tensile modulus (1.18 GPa), impact (72.68 J/m), flexural strength (63.54 MPa) and flexural modulus (2.16 GPa) were recorded, whereas beyond reduces the properties. Following tensile testing, the fractured cross‐sections of the composite were investigated using scanning electron microscope, which demonstrated that the alkali‐treated MAPFs reinforced polyester composite had fewer voids and better fiber bonding. Thermogravimetric and atomic force microscopy analysis show that alkali‐treated MAPFs are a viable reinforcement for polyester matrix due to higher degradation temperature and surface roughness observations. [ABSTRACT FROM AUTHOR]

The utilization of natural fibers rather than engineered filaments has turned into a subject of conversation in the composite industries. In this research, one of the natural fibers was synthesized from Pennisetum orientale grass and the surfaces were modified using sodium hydroxide (NaOH) chemically. Then they were used as reinforcement in vinyl ester polymer by different weight percentage (0, 5, 10, 15, 20, 25, and 30 wt%) for fabrication of composites. At different filler loading various mechanical properties were evaluated and discussed. The mechanical properties of the composites were observed to increase at beginning phase with increase in filler content till optimum (25 wt%) fiber loading and from there on declines. The composite at optimum fiber loading were characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, thermogravimetric analysis and compared with untreated composites. The findings give manufactures and engineer a general idea to use this composite for weight reduction especially in automotive applications. [ABSTRACT FROM AUTHOR]

Glass fiber reinforced epoxy matrix is modified with a hybrid combination of fillers, and composites were fabricated using the advanced pultrusion technique. The focus of the investigation was to comprehensively understand the synergy between the carbon nanofillers and the role of aluminum trihydride on the thermal characteristics. A ratio of 2 wt% of multiwalled carbon nanotubes and 3 wt% of graphene is established by prior optimization technique for improved thermal properties. Using X‐ray diffraction analysis, the presence of the two carbon fillers was confirmed. Aluminum trihydrate was incorporated in the epoxy matrix with the objective of improving the thermal properties. By thermogravimetric analysis and differential scanning calorimetry, assessment of the thermal properties of the composites has been undertaken. The use of the two carbon fillers leads to enhancement of the thermal properties and contrary to expectations, the composites with hybrid fillers undergo minimal degradation due to pyrolysis. Uniform dispersion of the nanoparticles and good interfacial bonding of fillers with the epoxy are observed to be critical for the enhancement of thermal properties. The ratio of the two carbon fillers used helps in their preferential alignment and hence significant improvements in thermal properties are observed. Glass transition temperature reveals a 13°C increase increases due to the inclusion of carbon nanofillers and aluminum trihydride. [ABSTRACT FROM AUTHOR]

The formation, and subsequent structural, thermal and adsorptive properties of single‐component metal–organic framework crystal‐glass composites (MOF‐CGCs) are investigated. A series of novel materials exhibiting chemically identical glassy and crystalline phases within the same material were produced, where crystalline ZIF‐62(Zn) was incorporated within an agZIF‐62(Zn) matrix. X‐ray diffraction showed that the crystalline phase was still present after heating to above the glass transition temperature of agZIF‐62(Zn), and interfacial compatibility between the crystalline and glassy phases was investigated using a mixed‐metal (ZIF‐62(Co))0.5(agZIF‐62(Zn))0.5 analogue. CO2 gas adsorption measurements showed that the CO2 uptakes of the MOF‐CGCs were between those of the crystalline and glassy phases. [ABSTRACT FROM AUTHOR]

Fusion bonding is understood to be the decisive mechanism for the interlayer strength in extrusion additive manufacturing. This study links the characteristic temperatures of semicrystalline thermoplastics, namely, PA6 with 40% carbon fibers, to the bond formation in respect to real‐world processing conditions. Based on theoretical investigations, a process window is proposed for bonding to occur without polymer degradation. This range from the glass transition to the initial degradation temperature was determined through differential scanning calorimetry and thermogravimetric analysis. A second process window for optimal bonding is proposed from the extrapolated onset crystallization temperature, Teic, to the melt temperature, Tm. The validation of these process windows was conducted by bending tests according to DIN EN 178. Tm was confirmed as the upper limit, with the part's geometric integrity compromised at higher temperatures. Teic had to be refuted as lower limit as no discrete reduction in bond strength was determined in alignment with Teic. Authors suggest the lower limit is defined by the lowest substrate temperature to lead to interface temperatures above the onset of melt temperature. By utilizing thermal analyses, less time and resources are required to detemine a suitable process window for extrusion additive manufacturing. [ABSTRACT FROM AUTHOR]

A 12.3 inch FHD flexible AMOLED display module for vehicle application was produced and the heat dissipation was studied. Passive thermal management technology was investigated and a simplified steady heat transfer model was established to analysis the thermal properties of the vehicle AMOLED display module. The simulation results were good consistent with the measured data. By optimizing the structure and materials of heat dissipation, the surface temperature of the AMOLED display module with the luminance of 800 cd/m2 at full white pattern can be decreased to 42.5 °C which was 4.1 °C lower than that of without any dissipation films. [ABSTRACT FROM AUTHOR]

BACKGROUND: Fruit mousses are products with a relatively low amount of dietary fiber in a single portion, but with additional portions of soluble fiber they may be good alternative to fiber‐rich snacks as take‐away food. In the present study, the properties of new soluble dextrin fiber (SDexF) from potato starch were assessed to establish whether it could be used to enrich fruit mousses. The properties of SDexF that can affect processing and storage stability of enriched mousses were studied and compared with those of native potato starch and semiproducts (resulting from various drying temperatures). The effect of the addition of SDexF on the pasting properties of mousse was also analyzed. RESULTS: The application of food‐grade hydrochloric and citric acids as catalysts in the dextrinization of food‐grade potato starch allowed to SDexF to be obtained. Despite the differences in characteristics of the semiproducts, the final SDexF preparations were very similar in the meaning of solubility, dextrose equivalent (DE), retrogradation, and pasting properties. SDexF preparations were characterized by a significantly lower retrogradation tendency, peak viscosity, final viscosity, and gelatinization enthalpy in comparison with both native starch and semiproducts. Soluble dextrin fiber was successfully added to banana‐apple mousse. The addition of SDexF to mousse did not cause any undesirable changes to the viscosity of the product, and surprisingly even resulted in mousse with lower viscosity. Turbidity and RVA studies revealed that SDexF was stable and retrogradation processes can be negligible during storage. CONCLUSION: The SDexF obtained from potato starch can be a novel functional substance to increase the dietary fiber content of fruit or fruit and vegetable mousses. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this work, high‐density lithium disilicate (LS2) vitreous systems were produced by melting and quenching under high pressure (7.7 GPa) following two distinct experimental routes. In the first case, LS2 glass was remelted at 7.7 GPa and 1600°C and, then, quenched. In the second case, a stoichiometric mixture of precursor oxides (Li2O and SiO2) was melted at 1600°C and 7.7 GPa before quenching. A reference LS2 glass sample was produced at atmospheric pressure using conventional melting and quenching procedure. The samples were characterized by X‐ray diffraction, differential thermal analysis, and instrumented ultramicro hardness measurements. X‐ray diffraction confirmed that all samples were amorphous and thermal analysis suggests that different glassy structures were produced depending on the route of synthesis. Hardness and elastic modulus of the glasses produced under high pressure were higher than those of the reference glass, reflecting the irreversible densification effect induced by the high‐pressure processing. [ABSTRACT FROM AUTHOR]

The main scope of this comprehensive study is to investigate the effects of poly(p‐benzophenoneoxycarbonylphenyl acrylate), poly(BPOCPA), which presenting as only graft units or both graft and ungrafted units in the matrix, on the fundamental features of isotactic polypropylene (IPP). The graft copolymerization of BPOCPA onto IPP was performed with the aid of bulk melt polymerization at varying monomer content levels ranging from 5% to 40%. The thermal behavior, crystal quality, mechanical performance, and surface morphology of the samples were investigated by means of differential scanning calorimeter, X‐ray diffractometer (XRD), universal mechanical test, and scanning electron microscope (SEM) techniques. Thermal analyses depicted that there existed the noteworthy enhancements in both crystalline melting temperatures and percent crystallinities of matrix polymers. Furthermore, according to XRD results, a and b parameters increased significantly at low percentages of the graft units, while the parameter c decreased in all products in consistence with the content. As for the mechanical characterization, the grafting led to remarkable improvements in modulus, tensile and impact strength of the products. SEM micrographs indicated that the samples were completely homogeneous without any phase separation and the products exhibited brittle nature with some ductility. [ABSTRACT FROM AUTHOR]

Expanded polystyrene (EPS) is a commonly used polymer in the packaging industry and for the thermal insulation of buildings. It has poor mechanical properties, which limit its application in some areas. A heat treatment was carried out on a sample of EPS, in order to improve its mechanical properties. The treatment consists of operations that combine the heating and cooling of the material. It is executed to improve the characteristics of the treated polymer and make it more favorable for use in new applications. In the case of EPS, this process changes the behavior of the polymer in a beneficial manner and maximizes its density and hardness. Indeed, the treated version shows interesting mechanical, tribological, and hygroscopic properties. This improvement was obtained mainly due to the morphological modification of the structure of EPS. Indeed, heat treatment leads to the creation of a polystyrene crust, which covers every EPS bead. This crust protects the cell structure of each bead against stretching and supports most of the load applied to the treated version of EPS. Thus, the treated EPS can be used not only for packaging and thermal insulation but also for more structural applications. [ABSTRACT FROM AUTHOR]

There are many coolants frequently used in the industry for controlling not only heat transfer, but also temperature distribution in a confined domain. However, little is known on the thermal properties of sodium droplets. The qualitative analysis of differential equations that model the thermal explosion, nonlinear dynamic of sodium droplet with variable thermophysical properties when thermal radiations are considered as suggested by Cogley et al, Sohrab et al, and P‐1 approximation Sazhin et al is deliberated upon in this study. The governing equations, first‐order nonlinear ordinary differential equations, are nondimensionalized using the appropriate similarity variables. The existence and uniqueness of the solutions, concavity, and convexity of the temperature distribution, and positivity nature of the solutions of the dimensionless governing equations are established. It is concluded that there exists a solution for a certain range of the admissible parameters and when the reduced activation energy is negative and temperature distribution fits concavity. More so, the major criteria to obtain a positive solution are outlined in this study. [ABSTRACT FROM AUTHOR]

A series of new mono‐ and bis‐terpyridine complexes [Mn(tpyOH)Cl2] (1), [Ni(tpyOH)2](PF6)2 (2) and [Zn(tpyO)(η1‐OCOCH3)(H2O)]⋅3H2O (4) containing 4′‐hydroxy‐2,2′:6′,2″‐terpyridine (tpyOH) were synthesized and structurally characterized using elemental analysis, infrared spectroscopy and single‐crystal X‐ray diffraction. The reaction of MnCl2 with tpyOH in a mixture of methanol and CH2Cl2 resulted in the formation of 1. The X‐ray crystal structure of 1 reveals that Mn(II) is penta‐coordinated by three nitrogen atoms from tpyOH and two Cl− in a slightly distorted trigonal bipyramidal geometry. Complex 2 was also prepared by the reaction of nickel(II) chloride with tpyOH in a methanolic medium in the presence of NH4PF6. Notably, the complex [Ni(tpyOH)(tpyO)]PF6 (3), obtained during the crystallization of 2 from dichloromethane, was characterized using X‐ray crystallography which shows that six nitrogen atoms from terpyridine ligands occupy the coordination sites around the Ni(II) centre in a distorted octahedral geometry with four longer bonds and two shorter NiN bonds. The reaction of zinc(II) acetate with tpyOH in a mixture of methanol and CH2Cl2 led to the formation of 4. The crystal structure of 4 reveals the formation of penta‐coordinated Zn(II) complex containing three nitrogen atoms from tpyO, a monodentate acetate ligand and one coordinated water molecule. Hirshfeld surface analyses and two‐dimensional fingerprint plots show that the main interactions are O...H/H...O contacts in 1, 3 and 4. The thermal decomposition reactions of 1, 2 and 4 were studied using thermogravimetric analysis in detail due to their different structures. The solution luminescence features of 1, 2 and 4 include high‐energy intense π → π* intraligand and low‐energy metal‐to‐ligand charge transfer transitions at room temperature. The calcination of the coordination complexes led to the formation of corresponding nano metal oxides. The products were structurally characterized using infrared spectroscopy, scanning electron microscopy and energy‐dispersive X‐ray spectroscopy. The average particle size using Scherrer's equation was calculated to be below 50 nm. [ABSTRACT FROM AUTHOR]

Two thermoset systems based on maleimides and diglycidyl ether of bisphenol A (DGEBA) cured with p‐aminobenzoic acid were characterized in terms of thermal and electrical behavior. Thermal characterization has been undertaken by means of thermogravimetric analysis in nitrogen atmosphere up to 600°C using simultaneous thermogravimetric/Fourier transform infrared/mass spectrometry (TG/FT‐IR/MS) analysis. In the first stage of thermal degradation, the global kinetic parameters [activation energy (Ea) and preexponential factor (log A1 (s−1))] were calculated using the isoconversional method of Friedman. The energies variation as well as the shape of the differential thermal analysis curves suggests that the thermal decomposition process occurred in multiple stages. The evolved gases analysis was conducted by simultaneous TG/FT‐IR/MS coupled techniques. Dielectric relaxation spectroscopy characterization was also made. [ABSTRACT FROM AUTHOR]

Antioxidants can effectively protect vegetable‐oil‐based lubricants against oxidative degradation and prolong their service life. A novel compound, (E)‐4‐({3,5‐di‐tert‐butyl‐2‐[(diphenylboranyl)oxy]benzylidene}amino)‐N‐phenylaniline (BSPD) or {2‐[(4‐anilinophenyl)iminomethyl‐κN]‐4,6‐di‐tert‐butylphenolato‐κO}diphenylboron, C39H41BN2O, was synthesized by a one‐pot reaction of the Schiff base bridged phenolic diphenylamine 2,4‐di‐tert‐butyl‐6‐{N‐[4‐(phenylamino)phenyl]carboximidoyl}phenol (SPD) with phenylboronic acid. The corresponding single‐crystal X‐ray study revealed that the B atom in BSPD has a typical tetrahedral geometry, and the N,O‐chelated six‐membered ring adopts a chair conformation. According to thermogravimetric analysis, the 5% weight‐loss temperature of BSPD increases to 328 °C and the 95% weight‐loss temperature is up to 414 °C. More importantly, the antioxidant capability of BSPD in vegetable oil is much better than that of commercial antioxidants [diphenylamine (DPA) and 2,6‐di‐tert‐butyl‐4‐methylphenol (BHT)] and unmodified SPD. [ABSTRACT FROM AUTHOR]

In this work, 3‐amino phenyl boronic acid (AB) was used as an aniline derivative in the preparation of polybenzoxazine based on phenol. In order to investigate the effect of boronic acid on thermal characteristics, polybenzoxazines based on pure aniline and 50% aniline and AB mixture were also prepared and analyzed. Significant improvements in thermal characteristics, increase in thermal stability and char yield, was recorded for the polymers based on AB or its mixture. This behavior was associated with crosslinked structures generated by condensation reactions of BOH groups. Morphologic and thermal characteristics of polybenzoxazines samples were investigated by NMR, FTIR, DSC, TGA, and direct pyrolysis mass spectrometry (DP‐MS) techniques. Application of DP‐MS technique also supplied additional information on crosslinked structures produced by boronic acid units. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1711–1716 [ABSTRACT FROM AUTHOR]

Carbon nanoparticles (CNPs) are isolated from chimney soot and characterised by various tools such as X‐ray diffraction, scanning electron microscopy, transmission electron microscopy and ultraviolet–visible spectroscopy. The X‐ray diffraction studies confirm the presence of C60 nanoparticles in the isolated sample. The thermal properties of the prepared CNPs are recorded using thermogravimetric analysis and differential thermal analysis. The analysis of the antibacterial activity of the synthesised CNPs against selected Gram‐positive and Gram‐negative bacterial strains is also investigated. The systematic study confirms that CNPs collected from chimney soot exhibit good antibacterial potency against Staphylococcus aureus, Streptococcus pyogenes, Klebsiella pneumoniae, and Proteus mirabilis. [ABSTRACT FROM AUTHOR]

Polyamide‐6 (PA‐6)/boehmite alumina (BA) nanocomposites were prepared via direct melt compounding. Structural, thermal and dielectric properties of 'as‐received' (including moisture) and 'dried' (thermally treated) specimens were examined. The BA nanofiller was homogeneously dispersed in the PA‐6 matrix. XRD and FTIR revealed that crystallization of PA‐6 in the γ phase was favoured over α phase with increasing BA content. The crystallinity index (CI) and the percentage of α and γ phases were also evaluated. Dried specimens exhibited a lower CI than as‐received specimens while the CI decreased with the addition of filler. Broadband dielectric spectroscopy revealed the presence of γ, β and α relaxations, the Maxwell–Wagner–Sillars effect and the contribution of conductivity relaxation in the as‐received samples. The drying procedure unmasked a double feature of both β and α modes. The results of the complementary techniques were analysed and the effects of moisture and/or the incorporation of BA nanofiller on the microstructure of the PA‐6 matrix are disclosed. © 2019 Society of Chemical Industry Polyamide‐6/boehmite alumina nanocomposites were produced and investigated by SEM, XRD, DSC and broadband dielectric spectroscopy techniques. Dielectric relaxations were assigned and interpreted in connection with the results of the complementary techniques. [ABSTRACT FROM AUTHOR]

Herein we report the discovery of the intrinsic mechanochemical reactivity of vinyl‐addition polynorbornene (VA‐PNB), which has strained bicyclic ring repeat units along the polymer backbone. VA‐PNBs with three different side chains were found to undergo ring‐opening olefination upon sonication in dilute solutions. The sonicated polymers exhibited spectroscopic signatures consistent with conversion of the bicyclic norbornane repeat units into the ring‐open isomer typical of polynorbornene made by ring‐opening metathesis polymerization (ROMP‐PNB). Thermal analysis and evaluation of chain‐scission kinetics suggest that sonication of VA‐PNB results in chain segments containing a statistical mixture of vinyl‐added and ROMP‐type repeat units. Cracking under the strain: Upon mechanochemical activation, repeat units in vinyl‐addition polynorbornenes (VA‐PNBs) underwent ring‐opening olefination to give repeat units typically obtained by ring‐opening metathesis polymerization (see scheme). The activated polymers and the parent polymers exhibited drastically different thermal properties. VA‐PNBs have significant potential as functional materials owing to their ready availability. [ABSTRACT FROM AUTHOR]

It is interesting to compare the residual strength of laminated carbon fiber reinforced polymer under thermal environments with finite heating rate, and laser irradiation with rapid heating rate. In these two conditions, heating rates are varied in two orders of magnitude, and thermally‐induced damage mechanisms are quite different, which may influence the performance of residual strength. Systematic experiments are performed to obtain the tensile failure behavior of laminated carbon fiber reinforced epoxy composites at different temperatures with a heating rate of about 102°C/min. In comparison, composite samples are subjected to laser irradiations of different power densities and then tested for residual strengths, the laser induced heating rate is above 104°C/min. Experimental results indicate that the residual strength decreases with the increase of heating temperatures and laser power densities, however the damage mechanisms for conventional heating are thermal pyrolysis, oxidation and delamination, whereas the main damage mechanisms for laser irradiation are thermal pyrolysis and fiber ablation. The experimentally obtained residual strength and modulus are also compared with those predicted by theoretical model. POLYM. ENG. SCI., 58:2311–2319, 2018. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Polyurethane elastomers (PUR) are used for the production of components subjected to abrasion. In many of these applications, the strength of polyurethane elastomers is not sufficient in spite of their modifications. In use PUR deteriorate as a result of mechanical and/or thermal degradation due to high loads and heat accumulation. To increase the strength properties of PUR and limit the accumulation of energy in the deformable material it is proposed to introduce to the PUR hollow glass spheres (HGSs). As part of the study the effect of these fillers on the properties of ureaurethanes was assessed. The resulting composites were characterized using thermal analysis techniques (DSC, TGA, and DMA), the chemical constitution was described via FTIR and the structure with use of SEM. The results of investigations of strength and tribological properties were presented. The filler is combined with the matrix by hydrogen bonding forming an additional cross‐linking of the macromolecules. Introduction of HGSs reduces the ability of the composites to suppress vibrations. POLYM. COMPOS., 39:2019–2028, 2018. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Dispersions of chemically modified multi‐walled carbon nanotubes (MWCNTs) are investigated by interacting of near‐infrared (NIR) laser irradiation power of 500 mW to determine the efficiency of heating. The resulting dispersions with modified CNTs are fed into the larva of Drosophila melanogaster, containing green fluorescent protein (GFP) reporter whose expression (synthesis of protein) is activated by hsp70 promoter. After NIR irradiation, it is found that organs of larvae gave GFP signal. The presence of a signal is associated with heating of organs to the heat shock temperature due to CNTs penetration. Thus, the experiment provides validation that nanotubes can penetrate into living Drosophila body. It is shown that the CNTs length and modification affect the penetration efficiency. [ABSTRACT FROM AUTHOR]

ABSTRACT Statistical copolymers of N-vinylpyrrolidone (NVP) with 2-(dimethylamino)ethyl methacrylate (DMAEMA) were prepared by Reversible Addition-Fragmentation chain Transfer Polymerization (RAFT), employing three different RAFT agents: [( O-ethylxanthyl)methyl]benzene, [1-( O-ethylxanthyl)ethyl]benzene, and O-ethyl S-(phthalimidylmethyl) xanthate. The reactivity ratios were estimated using the Fineman-Ross, inverted Fineman-Ross, Kelen-Tüdos, and extended Kelen-Tüdos graphical methods, along with the computer program COPOINT. Structural parameters of the copolymers were obtained by calculating the dyad sequence fractions and the mean sequence length. All the methods indicate that the DMAEMA reactivity ratio is much greater than the one of NVP, thus, the statistical copolymers are in fact pseudo-diblocks. The glass-transition temperature ( Tg) values of the copolymers were measured by Differential Scanning Calorimetry. Furthermore, a systematic and detailed investigation has been done, on the thermal degradation of the copolymers compared with the respective homopolymers, by Thermogravimetric Analysis, within the framework of the Ozawa-Flynn-Wall and Kissinger methodologies. Apparently, the thermal stability of the copolymers is influenced by both monomers and by the structure of the thiocarbonylthio end groups due to the RAFT agents. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3776-3787 [ABSTRACT FROM AUTHOR]

Low-density polyethylene was flame retarded by combinations of expandable graphite with either ethylenediamine phosphate or 3,5-diaminobenzoic acid phosphate. Cone calorimeter, laser pyrolysis, and open flame exposure tests (supported by video and infrared camera data capture and analysis) were conducted to assess ignition and burn behavior. Cone calorimeter results indicated substantial reductions in the peak heat release rates for all flame-retarded samples but with reduced ignition times and increased flame out times. Smoke generation was suppressed in the presence of expandable graphite. Infrared and video data from open flame fire tests indicated cohesive bonding of expanded strings and thermal shielding properties in all binary systems. All binary systems delivered fire retardation exceeding any of the single fire retardant compounds. They were also able to withstand higher temperatures before ignition, burn through, or sag occurred. All ethylenediamine phosphate-containing binary systems prevented sample burn through, maintaining structural integrity of samples until eventual melting of the polymer media occurred. Thermogravimetric analysis laser pyrolysis results confirmed the good thermal shielding imparted by the intumescent additives. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The SR-1, SR-2, Jhelum, and Pusa rice starches were extracted by the alkaline method and acetylated by using acetic anhydride to make modified food starches with high contents of type 4 resistant starch (RS4). The results revealed 6-10-fold increase in the RS4 content of rice starches via acetylation. The acetyl % and degree of substitution values (DS) of rice starches ranged from 1.83 to 2.31, and 0.05 to 0.10, respectively. The introduction of acetyl groups in starch chains was confirmed via Fourier transform infrared spectroscopy (FTIR). Acetylation was found to increase water absorption capacity, oil absorption capacity, bile-acid binding, swelling power, solubility index, light transmittance (%), and freeze-thaw stability, whereas amylose content, syneresis, pasting parameters, and thermal properties decreased with acetylation. The SEM micrographs of the acetylated rice starch revealed the presence of polyhedral granules with rough surfaces. Also fissures and deformed depressed zones were observed in some granules. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, flexible polyurethane foam samples were prepared using concentrations of up to 50% of two novel polycarbonate polyols, Polyol D 251-20 and Polyol D 351-30, derived from the copolymerization of carbon dioxide (CO2) and epoxides, to determine whether the final foam products meet automotive standards for use in seating applications. In other words, CO2-based polyols were substituted for a portion of petroleum-based polyols in the foam formulations. Characterization of the foam samples was carried out by mechanical, physical, and thermal analysis. Overall, inclusion of both types of CO2-based polyol led to an increase in wet compression set, compression modulus, compression stress at various strain levels, maximum tensile strength, Young's modulus, and tear resistance properties in the flexible polyurethane foams. Density, SAG factors, and elongation properties remained relatively constant compared to petroleum-based control samples. Dynamic mechanical thermal analysis showed increasing storage modulus with increasing concentrations of CO2-based polyol at temperatures below 0 °C. Thermogravimetric analysis showed that the thermal stability of the foam decreases with an increase in the concentration of CO2-based polyol. Images of foam samples were taken using a Keyence VHX digital microscope. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44086. [ABSTRACT FROM AUTHOR]

SUMMARY Organoclay glass fibre reinforced polymer (GFRP) nanocomposites are fabricated using the vacuum assisted resin transfer moulding. The unsaturated polyester resin is prepared with and without organoclay involving mechanical mixing, sonication, dilution solvent and heat treatment. Three levels of organophilic clay content are added, and its influences on the fire performance of composite samples are investigated. A novel numerical procedure combining pyrolysis analysis of the organoclay-composites and the fire dynamic simulation of the combustion process are developed to validate the thermal responses obtained from the cone calorimetry experiments. Kinetic parameters obtained from the TGA tests and pyrolysis analyses are used as inputs for the models measuring the fire growth index and total heat release. To account for multilayer composite structure and organoclay distribution, three numerical models are proposed including composite (CPS), component (CPN) and CPN-layer models. While CPS model assumes the homogeneity of the composite, later models consider multilayer effects with uniform (CPN model) or concentrated (CPN-layer model) distribution of organoclay. Numerical results are compared with experimental ones in terms of total heat release, fire growth index. Finally, the fire resistance and total smoke release of the polyester/glass composites with the addition of organoclay will be evaluated taking into account influences of the fabrication processes. [ABSTRACT FROM AUTHOR]

ABSTRACT The syntheses of a series of substituted polyphosphonates of the type [OP(X)(Ar)O(CH2)12] n (X = O, S, Se; Ar = phenyl, 2,2′-bithienyl-5-yl) are reported. The [ABSTRACT FROM AUTHOR]

ABSTRACT The thermal aging behavior of poly(3,3,3-trifluoropropyl)methylsiloxane was investigated by thermal gravimetric analysis and isothermal aging tests, and the results indicated the degradation mechanism II, oxidation scission of the side groups, played a more important role when the temperature was below 350 °C. The addition of ceria had significantly improved the thermal stability of fluorosilicone rubber (FSR) by inhibiting the oxidation scission. Moreover, two types of ceria including laminar-structure ceria (LS-CeO2) and nanoparticle ceria (N-CeO2) were prepared and surface was modified by KH570 and characterized by scanning electron microscopy, transmission electron microscope, and X-ray diffractometer. FSR incorporated with modified LS-CeO2 and N-CeO2 revealed a significant improvement on the heat resistant properties. In particular, after having been thermal oxidative aged for 70 h at 250 °C, FSR containing 2 wt % of modified N-CeO2 maintained 72.6% of tensile strength and 63.9% of elongation at break, respectively, while FSR without ceria completely failed. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44117. [ABSTRACT FROM AUTHOR]

A two-step solid-state reaction is proposed to synthesize monophasic cobalt tellurate Co3TeO6 (CTO), a type II multiferroic, using Co3O4 and TeO2 as the starting reagents. First step of the reaction results in the secondary monoclinic (P21/c) CoTeO4 compound, which on further calcination (second step) leads to the primary monoclinic (C2/c) Co3TeO6 phase. Highresolution synchrotron X-ray diffraction and the subsequent Rietveld analysis are used to probe different phases present in the synthesized CTO and to achieve its single phase. X-ray absorption near-edge structure studies at Co K and Te L edges reveal mixed oxidation states (Co2+/3+) of Co and hexavalent Te, respectively. Charge imbalance due to mixed valence Co ions has been attributed to cations vacancies. Enhanced multiferroic properties, such as effective magnetic moment, spin phonon coupling, etc., have been attributed to the aforementioned observations in grown ceramic CTO via proposed synthesis route. [ABSTRACT FROM AUTHOR]

ABSTRACT New flexible aliphatic oxazolidone-isocyanurate networks (AISOX) are obtained by reacting a low molecular weight diisocyanate (4,4′-methylene dicyclohexyl diisocyanate, H12MDI) and a macro-diepoxyde (poly(ethylene glycol) diglycidyl ether, Mn = 526, PEGDGE) in different molar ratio. The curing reaction, carried out from 25 °C to 200 °C, is studied by using DSC and FTIR. The effect of the molar ratio of the two monomers on thermal and mechanical properties of AISOX resins is investigated by DSC, thermogravimetric analysis, stress−strain measurements and optical microscopy. Independently from the feed composition, it is observed that the reaction steps are: (i) partial hydrolysis of isocyanate caused by water traces, (ii) incomplete trimerization of isocyanate to give isocyanurate, and (iii) formation of oxazolidone and complete conversion of isocyanate. At the highest concentration of the soft macrodiepoxyde (PEGDGE), the AISOX resin is in the rubbery state at room temperature and shows an elastomeric behavior. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43404. [ABSTRACT FROM AUTHOR]

The new flame-retardant plywood was manufactured by adding expanded vermiculite (EVMT) in the adhesive and by surface treatment as a flame-retardant coating. The study discussed the effect of EVMT to the limited oxygen index values of samples. The thermal degradation process of plywood samples has been investigated by thermal analysis. The result showed that EVMT increased all the limited oxygen index values of the treated samples and decreased the thermal activation energy at a high degree of degradation. Scanning electron microscope (FEI, Holland, The Netherlands) images showed that EVMT could form a protective coating, which improved the flame retardancy of plywood. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT High performance polymer blend of poly(ether ether ketone) (PEEK) and poly(ether imide) (PEI) was examined for their free volume behavior at different compositions of PEI using positron annihilation lifetime spectroscopy (PALS). The damping property of the blend was studied using tan-δ obtained from dynamic mechanical thermal analysis (DMTA). The dependence of tan-δ on temperature revealed that the blend is miscible in all compositions, in agreement with earlier studies. The tan-δ peak height is found to increase with increase in free volume fraction for the entire blend composition signifying that the free volume plays an imperative role in understanding the damping property. Using DMTA, master curves were obtained at a reference temperature T0 by applying the time-temperature-superposition (TTS) using Williams-Landel-Ferry (WLF) relationship. From the shift factor aT, the WLF coefficients [ABSTRACT FROM AUTHOR]

Epoxy hybrid composites fabricated by reinforcing 2-hydroxy ethyl acrylate (2-HEA) treated oil palm empty fruit bunch (EFB) and jute fibers. It assume that chemical modification of jute and oil palm EFB fibers increased fiber/matrix interfacial bonding and it results in enhanced thermal properties of hybrid composites. Dynamic mechanical and thermal analysis of treated hybrid composites was carried out. Results indicated that chemical modification of oil palm EFB and jute fibers affect the dynamic mechanical and thermal properties of hybrid composites. The storage modulus values of hybrid composites increases with chemical treatment and loss modulus increased with fiber treatment in hybrid composites. Damping factor peak values of treated hybrid composites shifted toward the lower temperature compared to both untreated hybrid composites. Cole-Cole analysis was made to understand the phase behaviour of the hybrid composites. Thermogravimetric analysis indicated an increased in thermal stability of hybrid composite with the incorporation of chemically modified fibers. POLYM. COMPOS., 36:1669-1674, 2015. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

ABSTRACT Composites comprising of polycrystalline triglycine sulphate (TGS) or its deuterated analog (DTGS) in powder form dispersed in polyurethane (PU) are synthesized for pyroelectric sensor applications. TGS and DTGS have high pyroelectric coefficients, but are susceptible to humidity, and PU is inherently electroactive. So composites made of TGS or DTGS dispersed in PU can be expected to have high pyroelectric coefficient as well as immunity to humidity. Composites with inclusion volume fraction between 0 and 0.25 are prepared, and their dielectric, pyroelectric, and thermal properties measured. In general, deuteration leads to decrease in dielectric constant and specific heat, but increase in thermal conductivity. The pyroelectric coefficient and figures of merit get enhanced significantly with deuteration as well as inclusion volume fraction. Comparison with similar composites shows that these samples have the highest values for figures of merit, indicating their potential use as thermal/infrared detectors that are immune to humidity. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42250. [ABSTRACT FROM AUTHOR]