A series of six symmetric pentablock terpolymers were synthesised using group transfer polymerisation (GTP). The chemical composition of these terpolymers comprises 45 wt% of oligo(ethylene glycol) methyl ether methacrylate (molar mass = 300 g mol⁻¹, OEGMA300, block A), 30 wt% of n-butyl methacrylate (BuMA, block B), and 25 wt% of di(ethylene glycol) methyl ether methacrylate (DEGMA, block C), aiming at a total molar mass (MM) of 9200 g mol⁻¹ with varied architectures, including ABCBA, CBABC, BCACB, ACBCA, BACAB, and CABAC. The impact of the polymer architecture (specifically the block number and sequence) was evaluated by comparing the properties of these pentablock terpolymers in aqueous solution, including micellisation, thermo-induced phase transition and gelation, and rheological properties, with each other and the triblock controls (ABC, ACB, and CAB). It was found that the cloud point temperature (T_cp) of the pentablock terpolymer solution is related to the corresponding micelle conformation, which is dependent on the architecture of the polymer chain. Moreover, the BCACB pentablock terpolymer demonstrated enhanced gelation performance, exhibiting a broader gelation range in terms of both concentration and temperature as well as higher storage modulus (G′), compared to other pentablock and triblock counterparts.

中文翻译：

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构型对甲基丙烯酸酯基对称五嵌段三元共聚物热诱导相变的影响


使用基团转移聚合 （GTP） 合成了一系列六种对称的五嵌段三元共聚物。这些三元共聚物的化学成分包括 45 wt% 的低聚（乙二醇）甲基丙烯酸甲醚（摩尔质量 = 300 g ^{mol-1，OEGMA300，Block} A），30 wt% 的甲基丙烯酸正丁酯（BuMA，Block B）和 25 wt% 的二（乙二醇）甲基醚甲基丙烯酸酯（DEGMA，Block C），目标是总摩尔质量 （MM） 为 9200 g ^mol-1具有不同的架构，包括 ABCBA、CBABC、BCACB、ACBCA、BACAB 和 CABAC。通过比较这些五嵌段三元共聚物在水溶液中的特性（包括胶束化、热诱导相变和凝胶化以及流变特性）以及三嵌段对照（ABC、ACB 和 CAB）来评估聚合物结构（特别是嵌段编号和序列）的影响。研究发现，五嵌段三元共聚物溶液的浊点温度 （T_cp） 与相应的胶束构象有关，而胶束构象则取决于聚合物链的结构。此外，BCACB 五嵌段三元共聚物表现出增强的凝胶化性能，与其他五嵌段和三嵌段共聚物相比，在浓度和温度方面表现出更宽的凝胶化范围以及更高的储能模量 （G′）。