Search

In this study, almond shell waste (ASW) as filling material, pure (ER), and waste polystyrene modified bisphenol-A type epoxy resin (ER-PS) were used to obtain biobased composite materials. The modification of ASW was carried out with NaOH and linoleic acid (LnA). Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Particle size distribution analyses were used in the characterization of ASW. Composites were prepared at filling ratios of 10-20-30-40-50% by mass using the casting technique. The morphology of the composites was characterized by SEM. The effects of epoxy matrix type and BK filling ratio on composites' mechanical, thermal, and water sorption properties were investigated. Tensile strength and modulus of elasticity (e-modulus) values of ERPS/ASW composites were lower, and tensile elongation values were higher than ER/ASW composites. The highest tensile strength values of 95-129 MPa were obtained for LnA modified ASW composites. The order of the tensile strength of the prepared ER matrix composites according to the filler type is: linoleic acid-modified ASW (LnA-ASW)>NaOH treated ASW (NaOH-ASW) > unmodified ASW. The most suitable ASW ratio was found as 30% by mass. e-modulus values of all modified ASW composites were higher than the epoxy matrix. According to the hardness test results, there was no significant difference between the composites. The water sorption of the composites increased depending on the ASW ratio and had a weakening effect on the mechanical properties. [ABSTRACT FROM AUTHOR]

In this study, it was aimed to investigate the effect of zinc borate additive of thermal properties on nanofiber textile surfaces produced by doping different amounts of zinc borate into polyacrylonitrile-co-vinyl acetate (P(AN-VAc)). For this purpose, nanofiber textile surfaces were produced from the zinc borate doped and undoped P(AN-VAc) solutions prepared with a 10% concentration in dimethylformamide by electrospinning method. Some analyzes and tests were carried out to determine the structural, morphological, physical, mechanical and thermal properties of the zinc borate doped and undoped nanofiber textile surfaces produced. The presence of zinc borate was detected on zinc borate doped nanofiber surfaces produced as a result of Fourier transform infrared spectroscopy (FTIR) and energy dispersive X-ray spectroscopy (EDX) analyses. The morphological properties of the produced surfaces were investigated by scanning electron microscopy (SEM) and it was observed that uniform nanofiber structure was formed in all samples. As a result of tensile strength tests, it was determined that the zinc borate additive reduces values of tensile strength and elongation of nanofiber surfaces. The thermal properties of all the produced nanofiber textile surfaces were examined by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), limit oxygen index (LOI) and vertical flammability tests. As a result of the thermal analyses and tests, it was determined that the zinc borate additives improve the thermal properties of the P(AN-VAc) nanofiber textile surfaces and the thermal resistances of them increases with the increase of the zinc borate additive. [ABSTRACT FROM AUTHOR]