Armstrong Daniel P, Mineart Kenneth P, Lee Byeongdu, Spontak Richard J
Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States.
ACS Macro Lett. 2016 Nov 15;5(11):1273-1277. doi: 10.1021/acsmacrolett.6b00677. Epub 2016 Nov 1.
Since selectively swollen thermoplastic elastomer gels (TPEGs) afford a wide range of beneficial properties that open new doors to developing elastomer-based technologies, we examine the unique structure-property behavior of TPEGs composed of olefinic block copolymers (OBCs) in this study. Unlike their styrenic counterparts typically possessing two chemically different blocks, this class of multiblock copolymers consists of linear polyethylene hard blocks and poly(ethylene--α-octene) soft blocks, in which case, microphase separation between the hard and the soft blocks is accompanied by crystallization of the hard blocks. Here, we prepare olefinic TPEGs (OTPEGs) through the incorporation of a primarily aliphatic oil that selectively swells the soft block and investigate the resultant morphological features through the use of polarized light microscopy and small-/wide-angle X-ray scattering. These features are correlated with thermal and mechanical property measurements from calorimetry, rheology, and extensiometry to elucidate the roles of crystallization and self-assembly on gel characteristics and establish useful structure-property relationships.
由于选择性溶胀的热塑性弹性体凝胶（TPEG）具有广泛的有益特性，为开发基于弹性体的技术打开了新的大门，因此在本研究中，我们研究了由烯烃嵌段共聚物（OBC）组成的TPEG的独特结构-性能行为。与通常具有两个化学性质不同嵌段的苯乙烯类对应物不同，这类多嵌段共聚物由线性聚乙烯硬段和聚（乙烯-α-辛烯）软段组成，在这种情况下，硬段和软段之间的微相分离伴随着硬段的结晶。在这里，我们通过加入一种主要的脂肪族油来制备烯烃TPEG（OTPEG），这种油会选择性地溶胀软段，并通过偏光显微镜和小角/广角X射线散射来研究由此产生的形态特征。这些特征与量热法、流变学和拉伸测量法的热性能和机械性能测量结果相关，以阐明结晶和自组装对凝胶特性的作用，并建立有用的结构-性能关系。
