Biomaterials Research Group, Manchester Materials Science Centre, School of Materials, The University of Manchester, Grosvenor Street, Manchester M1 7HS, UK.
J Colloid Interface Sci. 2014 Feb 1;415:151-8. doi: 10.1016/j.jcis.2013.09.030. Epub 2013 Sep 21.
Microgels are swollen crosslinked polymer colloid particles. We used non-aqueous dispersion polymerisation to prepare new water-swellable microgels containing N-vinylformamide (NVF), glycidylmethacrylate (GMA) and an alkali-stable crosslinker, 2-(N-vinylformamido)ethyl ether (NVE). The microgel particles had a core that was rich in NVF. The shell contained GMA and NVF. In order to expose the amine functionality, alkaline hydrolysis was used, transforming the NVF groups in the shell to vinylamine (VAM) while leaving most NVF in the core untouched. The hydrolysed microgels (H-NVF-GMA-NVE) were cationic at low pH and were shown to have polyampholyte behaviour. Inclusion of NVE had the beneficial effects of preventing microphase separation at the microgel surface and stabilising the polyampholyte structure against excessive fragmentation during hydrolysis. These new water-swellable core-shell microgels were prepared using scalable methods and may enable future preparation of functionalised core-shell microgels and composites.
微凝胶是溶胀的交联聚合物胶体颗粒。我们使用非水相分散聚合制备了新的可溶胀水的微凝胶，其中含有 N-乙烯基甲酰胺（NVF）、甲基丙烯酸缩水甘油酯（GMA）和一种碱稳定的交联剂 2-（N-乙烯基甲酰胺基）乙醚（NVE）。微凝胶颗粒的核富含 NVF。壳层含有 GMA 和 NVF。为了暴露胺官能团，我们使用碱性水解，将壳层中的 NVF 基团转化为乙烯胺（VAM），而核心中的大多数 NVF 保持不变。水解后的微凝胶（H-NVF-GMA-NVE）在低 pH 值下呈阳离子性，并表现出聚两性电解质行为。NVE 的加入具有防止微凝胶表面微相分离和稳定聚两性电解质结构的有益效果，防止在水解过程中过度碎片化。这些新的可溶胀的核壳微凝胶是通过可扩展的方法制备的，可能会为未来制备功能化的核壳微凝胶和复合材料提供帮助。
