Temperature-dependent self-assembly and rheological behavior of a thermoreversible pmma–PnBA–PMMA triblock copolymer gel
Temperature-dependent self-assembly and rheological behavior of a thermoreversible pmma–PnBA–PMMA triblock copolymer gel
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热可逆 pmma-PnBA-PMMA 三嵌段共聚物凝胶的温度依赖性自组装和流变行为
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发表时间：
2017
期刊：
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通讯作者：
S. Kundu
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作者：
M. Zabet;Satish Mishra;Ramiz Boy;K. Walters;A. Naskar;S. Kundu
三嵌段共聚物在中间嵌段选择性溶剂中的自组装和力学性能具有广泛的应用前景。在这里，我们报道了一种ABA三嵌段共聚物[PMMA-PnBA-PMMA]在两种不同的中间嵌段选择性溶剂正丁醇和2-乙基-1-己醇中的物理组装。在−80°C到60°C的温度范围内，从溶剂熔点附近到凝胶温度以上，研究了末端嵌段缔合导致的凝胶形成和相应的机械性能变化。剪切流变仪、热分析和小角中子散射数据揭示了随着温度的降低，这些体系中结构的形成和从液态到凝胶态再到渗流团簇网络的转变。聚集态PMMA端块具有玻璃化转变温度。我们的结果为理解自组装三嵌段共聚物凝胶在大长度尺度和宽温度范围内的结构变化提供了新的理解。©2017威利期刊公司J.Polym。科学，B部分：多晶硅。太棒了。2017年，55,877-887
Self-assembly and mechanical properties of triblock copolymers in a mid-block selective solvent are of interest in many applications. Herein, we report physical assembly of an ABA triblock copolymer, [PMMA–PnBA–PMMA] in two different mid-block selective solvents, n-butanol and 2-ethyl-1-hexanol. Gel formation resulting from end-block associations and the corresponding changes in mechanical properties have been investigated over a temperature range of −80 °C to 60 °C, from near the solvent melting points to above the gelation temperature. Shear-rheometry, thermal analysis, and small-angle neutron scattering data reveal formation and transition of structure in these systems from a liquid state to a gel state to a percolated cluster network with decrease in temperature. The aggregated PMMA end-blocks display a glass transition temperature. Our results provide new understanding into the structural changes of a self-assembled triblock copolymer gel over a large length scale and wide temperature range. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 877–887