Nederberg Fredrik, Trang Vivian, Pratt Russell C, Mason Andrew F, Frank Curtis W, Waymouth Robert M, Hedrick James L
IBM Almaden Research Center, 650 Harry Road, San Jose, CA 95120, USA.
Biomacromolecules. 2007 Nov;8(11):3294-7. doi: 10.1021/bm700895d.
Herein, we describe an organocatalytic living polymerization approach to network and subsequent hydrogel formation. Cyclic carbonate-functionalized macromolecules were ring-opened using an alcoholic initiator in the presence of an organic catalyst, amidine 1,8-diazabicyclo[5.4.0]undec-7-ene. A model reaction for the cross-linking identified monomer concentration-dependent reaction regimes, and enhanced kinetic control was demonstrated by introducing a co-monomer, trimethylene carbonate. The addition of the co-monomer facilitated near-quantitative conversion of monomer to polymer (>96%). Resulting poly(ethylene glycol) networks swell significantly in water, and an open co-continuous (water-gel) porous structure was observed by scanning electron microscopy. The organocatalytic ring-opening polymerization of cyclic carbonate functional macromonomers using alcoholic initiators provides a simple, efficient, and versatile approach to hydrogel networks.
在此，我们描述了一种用于形成网络及后续水凝胶的有机催化活性聚合方法。在有机催化剂1,8 - 二氮杂双环[5.4.0]十一碳-7-烯（DBU）存在下，使用醇类引发剂使环状碳酸酯官能化的大分子发生开环反应。交联的模型反应确定了单体浓度依赖性反应体系，并且通过引入共聚单体碳酸三亚甲酯证明了动力学控制得到增强。共聚单体的加入促进了单体向聚合物的近定量转化（>96%）。所得聚乙二醇网络在水中显著溶胀，通过扫描电子显微镜观察到开放的共连续（水-凝胶）多孔结构。使用醇类引发剂对环状碳酸酯官能化大分子单体进行有机催化开环聚合，为水凝胶网络提供了一种简单、高效且通用的方法。
