Impact strength elastomer composites based on polystyrene components separated from waste electrical and electronic equipment

The reuse of plastic components of waste electrical and electronic equipment (WEEE) is an important concern both for environmental issues and to preserve the material resources, with minimum energy consumption. Considering that polystyrene fraction was reported as approximate 80% of the total amount of WEEE plastic, this article aims to evaluate the recycling of this fraction, without separation by components, by melt compounding with styrene-butadiene block-copolymer (SBS) and hydrogenated and maleinized SBS, the blend of the two elastomers acting both as an impact modifier and compatibilizer. The composites are characterized by mechanical analysis, impact tests, dynamic mechanical analysis, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, energy dispersive X-ray analysis, and X-ray diffraction. The recycling conditions of the polystyrene fraction as composites without eliminating the WEEE additives for improved UV and flame resistance, with physical mechanical properties comparable to those of high-impact polystyrene resulted from the study. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48329.     

Mechanical Properties of Nylon 6,6/Polyvinyl Butyral Blends

The mechanical properties of Nylon 6,6 blended with recycled scrap material, polyvinyl butyral (PVB), using maleated styrene-ethylene-butylene-styrene block copolymer (SEBS-g-MA) as a compatibilizer are discussed. Control samples of Nylon 6,6/PVB blends and Nylon 6,6/SEBS-g-MA blends were also compared. The results show Nylon 6,6/PVB blends give higher tensile strength than Nylon 6,6/SEBS-g-MA blends. As for Nylon 6,6/SEBS-g-MA/PVB blends, impact strength increases with increasing the dosage of SEBS-g-MA. PVB improves flexural and tensile properties but sacrifices impact strength of the blends. Meanwhile, the ductile-brittle transition temperature (DBTT) increases with increasing PVB content. Through morphology observation, hole sizes are smaller with increasing SEBS-g-MA content. In summary, suitable amounts of PVB scrap are vital to balance both rigidity and toughness of blends. This study helps to understand the role of PVB in Nylon 6,6 blend systems, which allows PVB to find a practical application based on economic and environmental concerns.     

Effects of electron beam irradiation on the structure–property behavior of blends based on low density polyethylene and styrene-ethylene-butylene-styrene-block copolymers

Low density polyethylene (LDPE) blends with different additives were exposed to various doses of electron beam irradiation. The additives used were styrene-ethylene-butylene-styrene-block copolymers (SEBS), styrene-ethylene-butylene-styrene-block copolymer grafted with maleic anhydride (SEBS-g-MA) and mineral compounds. The structure–property behavior of electron beam irradiated blends was characterized in terms of mechanical, thermal, and electrical resistivity properties. The results indicated that the unirradiated LDPE blends with the different compositions showed improved mechanical properties, thermal and volume resistivity properties than pure LDPE. However, the improvement in properties of unirradiated blends by using SEBS-g-MA was higher than using SEBS copolymer. Further improvement in the mechanical, thermal and electrical properties of the LDPE blends was achieved after electron beam irradiation. The limited oxygen index (LOI) data revealed that the LDPE/SEBS-g-MA/ATH blend was changed from combustible to self-extinguishing material after electron beam irradiation to a dose of 100 kGy. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

SEBS-g-MA橡胶颗粒及有机纳米黏土增强尼龙66复合材料的摩擦磨损性能

采用M-200环-块接触型磨损实验机,分别考察了尼龙66(PA66)和SEBS-g-MA橡胶颗粒或有机纳米黏土或两者增强尼龙66在干摩擦及水润滑条件下的摩擦学性能,利用扫描电子显微镜和差示扫描量热仪对材料的磨损表面和碎片进行了观察与分析。结果表明,干摩擦条件下,PA 66+(SEBS-g-MA+organoclay)纳米复合材料的摩擦系数和磨损质量最低;当摩擦表面的温度在玻璃化转变温度T_g附近时,试样整体由于软化或者熔融而发生粘着磨损。     

Mechanical,Morphological and Thermal Properties of Polycarbonate/SEBS-G-MA/Montmorillonite Nanocomposites

Nanocomposites based on polycarbonate (PC) containing sodium montmorillonite (NaMMT) and maleic anhydride grafted styrene-ethylene/butylene-styrene (SEBS-g-MA) were prepared by melt compounding method followed by injection molding. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results revealed the formation of intercalated nanocomposites. Incorporation of SEBS-g-MA into the PC/MMT nanocomposites enhanced ductility and impact strength but slightly reduced tensile strength and stiffness. The glass transition temperature (T _g – detected from DMTA) and onset temperature (T _onset – detected from TGA) of the PC nanocomposites was increased in the presence of SEBS-g-MA. For this PC/NaMMT system, SEBS-g-MA could act as an effective toughening agent.     

Effects of SEBS-g-MA on tribological behaviour of nylon 66/organoclay nanocomposites

The tribological behaviour of nylon 66, nylon 66/organoclay nanocomposites and nylon 66/(SEBS-g-MA+organoclay) nanocomposites was studied by means of a pin-on-disk apparatus. The morphologies of the transfer films and the worn surfaces of specimens were observed with an optical microscope and a scanning electron microscopy (SEM). Wear of all of the specimens increases with increasing load; meanwhile the coefficient of friction almost linearly decreases. Wear of nylon 66/organoclay is larger than that of nylon 66. Adding SEBS-g-MA to the nylon 66/organoclay improves the wear resistance. The coefficient of friction of nylon 66/organoclay is slightly less than that of nylon 66 at various loads. The coefficient of friction of nylon 66/(SEBS-g-MA+organoclay) is the lowest at every load. If the transfer film is thin, uniform and continuous, the wear loss and the coefficient of friction are low.     

Unraveling the Potential of Innovative Eco-friendly Thermoplastic Starch/SEBS-g-MA/Graphene Oxide Bionanocomposites

The increasing focus on bionanocomposites as environmentally friendly solutions for sustainable applications forms the crux of this study. This study explores the influence of incorporating 2% graphene oxide (GO) on the mechanical and thermal characteristics of blends containing glycerol plasticized thermoplastic starch (TPS) and polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene-graft-maleic anhydride (SEBS-g-MA), based matrix films through a solution casting method. Starch is successfully obtained from three varied sources: corn, cassava, and potato, with confirmation via fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. The authors formulate and examine varying proportions of TPS/SEBS-g-MA (ranging from 10 to 50 wt.%), focusing on their biodegradability, and find that a 10 wt.% SEBS-g-MA concentration yields optimal degradation rates, thus this is kept constant. The bionanocomposite films are probed using techniques such as FTIR, XRD, mechanical strength testing, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), water absorption, and biodegradability studies. These results indicate that GO incorporation results in a robust hydrogen bonding network within the cassava starch-based bionanocomposite films, enhancing their mechanical strength while decreasing their moisture absorption. Upgraded thermal properties of these films are also evident from the results. Consequently, these materials show promising utility, particularly in the realm of food packaging.