Abstract

Merging the characteristics of thermoresponsive and stimuli-degradable polymers yields so-called transiently thermoresponsive polymers, which can find application for the design of injectable gels, nanoparticles, etc. within a biomedical context. Among these polymers, only a limited number is reported which shows selective degradation under mild acidic conditions. However, extension of the library of transiently thermoresponsive polymers is desired to broadening the biomaterials toolbox to suit specific needs. Three monomers were developed by modification of 2-hydroxyethylacrylamide (HEAm) via tetrahydropyranylation or -furanylation with 3,4-dihydro-2H-pyran (DHP), 2,3-dihydrofuran (DHF) or 2,3-dihydro-5-methylfuran (MeDHF). The presence of an acetal or ketal bond provided the monomers a pH-dependent hydrolysis behavior ranging from minutes to days. RAFT polymerisation allowed for the construction of homopolymers with temperature responsive behavior and pH-dependent hydrolysis which was strongly influenced by nature of the monomeric repeating units.

中文翻译：

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用环状缩醛重复单元调节瞬态热敏聚丙烯酰胺的酸敏感性

摘要

融合热响应性和刺激降解性聚合物的特性，可以得到所谓的瞬态热响应性聚合物，该瞬态热响应性聚合物可以在生物医学领域内用于可注射凝胶，纳米颗粒等的设计。在这些聚合物中，仅报道了有限数量的聚合物，其在温和的酸性条件下表现出选择性降解。但是，需要扩展瞬态热响应性聚合物库以扩展生物材料工具箱以适应特定需求。通过用3,4-二氢-2 H进行四氢吡喃基化或-呋喃基化反应对2-羟乙基丙烯酰胺（HEAm）进行修饰来开发三种单体-吡喃（DHP），2,3-二氢呋喃（DHF）或2,3-二氢-5-甲基呋喃（MeDHF）。缩醛或缩酮键的存在为单体提供了数分钟至数天的pH依赖性水解行为。RAFT聚合可构建具有温度响应行为和pH依赖性水解的均聚物，而该单体受单体重复单元的性质影响很大。