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以新戊二醇为核,2,2-二羟甲基丙酸为支化单体,通过准一步熔融缩聚法合成了不同代数的脂肪族超支化聚酯.采用FT-IR、1H NMR、GPC及TGA方法对所合成的超支化聚酯的结构与性能进行了表征和分析.对第三代超支化聚酯而言,GPC分析测得重均分子量为2615g/mol,质均分子量为1536 g/mol,分子量分布为1.41;1H NMR分析测得其支化度为0.49,热重分析表明温度高达300℃该聚酯才失重5wt%.此外还讨论了第三代脂肪族超支化聚酯熔融缩聚过程羧基的变化,结果表明,由于反应生成的水不能完全除去,羧基的最终转化率不可能达到100%.
Using neopentyl glycol as nucleus and 2,2-dimethylolpropionic acid as the branched monomer, different algebraic aliphatic hyperbranched polyesters were synthesized via quasi-one-step melt polycondensation. FT-IR, 1H NMR, GPC and TGA were used to characterize and analyze the structure and properties of the synthesized hyperbranched polyesters. For the third generation of hyperbranched polyesters, GPC analysis showed that the weight average molecular weight was 2615 g / mol and the weight average molecular weight was 1536 g / mol and a molecular weight distribution of 1.41. The degree of branching was found to be 0.49 by 1 H NMR analysis and thermogravimetric analysis showed that the polyester lost 5 wt% at temperatures up to 300 ° C. In addition, the third generation aliphatic hyperbranched polyesters The results showed that the final conversion of carboxyl groups could not reach 100% due to the incomplete removal of water from the reaction.