In this study, a series of styrene-b-ethylene-co-butylene-b-styrene copolymer (SEBS)/polypropylene (PP)/oil blends with different kinds of oil composition was developed through melt blending. The effect of oil with different composition and properties on its phase equilibrium and "redistribution" in multiphasic SEBS elastomer was systematically studied for the first time. Moreover, an integral influencing mechanism of oil composition on the structure and properties of SEBS/PP/oil blends was also put forward. The mineral oil was mainly distributed in ethylene/butylene (EB)/PP phase, which greatly enhanced the processing flowability of SEBS/PP/oil blends. With increasing oil C N content, a redistribution of oil appeared and excess naphthenic oil (NO) entered the interphase of soft and hard phases. The dynamic mechanical thermal analysis (DMTA) analysis indicated that the polystyrene (PS) phase was plasticized, which also helped to improve the processing fluidity of blends. However, the plasticizing of physical cross-linking point PS resulted in a decrease in mechanical strength and thermal stability. Small-angle X-ray scattering (SAXS) and transmission electron microscope (TEM) results showed that PS phase (45 nm to 55 nm) cylindrically distributed in EB/PP/oil matrix, the excess NO in the interphase enlarged the distance between PS phase and widen the escape channel for oil migration. At over 45% oil C N content, the electron density difference between soft and hard phases reduced to the minimum, same as T gPS , indicating a deeper plasticizing effect. The PS phase swelled and exhibited elastic behavior; thus, the force could be uniformly transferred between two phases. Importantly, a recover in strength and thermal stability was observed in O-5 blend.This work significantly filled the gap of studies in oil-extended thermoplastic elastomers (TPEs), exhibiting great theoretical guiding significance and application value.
In the past few decades, considerable attention has been paid to the thermoplastic elastomer (TPE). Among them, hydrogenated styrenic block copolymers (HSBCs) have attracted extensive interest because of outstanding ozone resistance, remarkable aging properties, and environmental friendliness. Therefore, theoretical and experimental investigations on the HSBCs/PP/oil composites have been reported many times, but the influence of molecular structure on the structure and properties of composites has yet to be identified. In this study, three HSBCs with different molecular structures were used as the research object to systematically study the effects of their molecular structural differences on the aggregate structure, microstructural, mechanical, and thermal properties of HSBCs/PP/oil composites. It was found thatthe content of side groups in the molecular chain was the main factor affecting the structure and performance of the HSBCs/PP/oil composites. This research can provide theoretical guidance for the molecular design and structural control of the new HSBC, so it has obvious theoretical significance and practical value.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.