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The exploration of new natural fibers in the field of polymer composites can contribute to increase the invention of natural reinforcements and expand their use in possible applications. In the present work, the physico-chemical, thermal, tensile and morphological properties of Furcraea foetida (FF) fiber are presented for the first time. Chemical analysis results shows that FF has relatively higher cellulose (68.35%) with lower hemicelluloses (11.46%) and lignin (12.32%). Structural analysis of FF was conducted by Fourier transform infrared and 13 C (CP-MAS) nuclear magnetic resonance spectroscopy. X-ray diffraction (XRD) analysis evidenced that FF has crystallinity index of 52.6% with crystalline size of 28.36 nmThe surface morphology of FF was investigated by scanning electron microscopy (SEM), energy dispersive X-ray micro analyzer (EDX) and atomic force microscopy (AFM). The thermogravimetric analysis (TGA) reveals thermal constancy of the fiber upto 320.5 °C with the kinetic activation energy of 66.64 kJ/mol, which can be used as reinforcements in thermoplastic green composite whose working temperatures is below 300 °C. The FF results were compared with those of other natural fibers, and indicated as a suitable alternative source for composite manufacture. [ABSTRACT FROM AUTHOR]

Highlights: [•] Amylose content was the main factor influencing the banana starch properties. [•] All the starches exhibited Type III behaviour (G″ overshoot). [•] Lixiviated amylose formed a complex gel reinforced by swollen starch granules. [ABSTRACT FROM AUTHOR]

Highlights: [•] Cellulose/SiC nanobiocomposites were prepared by green technique. [•] Tensile property of cellulose was improved due to reinforcement of nano SiC. [•] Thermal stability of cellulose was enhanced dispersion of nano SiC. [•] Oxygen permeability of nanobiocomposites was reduced by three times. [ABSTRACT FROM AUTHOR]

Abstract: Organic modification of starch nanoparticles was carried out at room temperature to obtain nanosized hydrophobic derivatives. The particle size of the modified starch nanoparticles obtained by transmission electron microscopy (TEM) and X-ray diffraction (XRD) was found out to be around 50nm. The hydrophobic starch derivatives were used to prepare bionanocomposites of natural rubber by mastication process. The properties were compared with composites obtained from untreated starch nanoparticles and carbon black. Up to 30phr of the fillers were successfully incorporated leading to an enhancement in mechanical as well as thermal properties. Scanning electron microscopy (SEM) revealed single phase morphology of nanobiocomposites indicating compatibility of the filler and matrix. Dynamic mechanical properties were seen as a broad tan delta peak over a large range of temperature. It was observed that modified starch nanoparticles could be a potential substitute for carbon black as reinforcing agents and as promising materials for vibration damping applications. [Copyright &y& Elsevier]

Abstract: Physically crosslinked hydrogels composed of different amounts of dextran in PVA matrix were prepared by applying freeze–thaw cycles to their aqueous solutions. Morphology, thermal properties and FTIR spectra of the resulting blend xerogels were examined by SEM, DSC, TGA and FTIR spectroscopy. Blend xerogels containing 10% (w/w) dextran showed more compatibility/miscibility according to SEM and DSC results. The T g of the xerogels did not show any significant changes with increased dextran content. Introducing dextran into the freeze–thawed PVA structure affected crystal size distribution of PVA; and hence thermal degradation behavior of the xerogels. An increase in dextran content resulted in broader crystal size distribution; better and still lower thermal stability in comparison to virgin PVA and freeze–thawed PVA, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Shape memory polyurethanes (SMPUs) are playing a prominent role in biomedical, self repairing, aerospace and smart materials. Shape memory polyurethanes (SMPUs) were prepared from polycaprolactone diol 4000 (PCL4000), 1-4-butanediol (BDO), chitin, dimethylol propionic acid (DMPA), triethylamine (TEA), and 4, 4′-diphenylmethane diisocyanate (MDI). Trifunctional characteristics of chitin enhanced the thermal and mechanical properties of SMPUs. DMPA was used to obtain higher recovery and lower residual strain. The morphology, microstructure, mechanical, thermo-mechanical, and shape memory properties of synthesized SMPUs were investigated using Fourier transform infrared (FT-IR), differential scanning calorimetry (DSC), dynamic mechanical thermal analyzer (DMTA) and tensile testing techniques. The results showed that crosslinked SMPUs have better thermal and thermo-mechanical properties, and a good shape memory effect. [Copyright &y& Elsevier]

Abstract: The biodegradable poly(propylene carbonate) (PPC)/glycerol-plasticized thermoplastic dried starch (GPTPS) composites are prepared in a screw extruder. The dried starch is used, because the moisture in native starch easily induces the degradation of PPC during the processing. The effects of succinic anhydride (SA) on the morphology, thermal properties, dynamic mechanical thermal analysis, as well as mechanical properties of PPC/GPTPS composites, are investigated. Scanning Electron Microscope (SEM) shows that SA improves interfacial adhesion between PPC and GPTPS. Fourier Transform Infrared (FTIR) Spectroscopy reveals that SA can improve the interaction between PPC and GPTPS. Thermogravimetric Analysis (TGA) results show that SA leads a significant improvement of thermal stability for PPC/GPTPS composites. Mechanical testing illustrates that SA can increase mechanical properties of PPC/GPTPS composites. The tensile strength and elongation at break of PPC/GPTPS/SA(75/25/1) composite can reach 19.4MPa and 88.5%, respectively. [Copyright &y& Elsevier]

Abstract: Blends of thermoplastic acetylated starch (TPAS) and poly(ethylene-co-vinyl alcohol) (EVOH) were prepared with different components by melt blending method and the mechanical and thermal properties of these blends were investigated. Tensile testing shows that with the increasing of EVOH content, the mechanical properties of TPAS/EVOH blends are improved significantly. Dynamic mechanical analysis (DMA) indicates that there is a good miscibility between TPAS and EVOH, and the molecular interactions of TPAS/EVOH blends become stronger with the increasing of EVOH content. Differential scanning calorimetry (DSC) results also reveal that there are some interactions between TPAS and EVOH that can interrupt the crystallization of EVOH. It can be inferred from thermogravimetry analysis (TGA) that EVOH can increase the thermal stability of TPAS. [Copyright &y& Elsevier]