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论文类型：期刊论文

发表时间：2013-03-15

发表刊物：JOURNAL OF APPLIED POLYMER SCIENCE

收录刊物：SCIE、EI、Scopus

卷号：127

期号：6

页面范围：4280-4287

ISSN号：0021-8995

关键字：poly(N-isopropylacrylamide); hydrogen bonding; hydrophobic interaction; hydrodynamic diameter; lower critical solution temperature; dynamic light scattering

摘要：A novel copolymer, poly(N-isopropylacrylamide-co-hydroxypropyl methacrylate-co-3-trimethoxysilypropyl methacrylate) has been synthesized and the hydrodynamic diameters in various aqueous solutions under different temperatures are determined by dynamic light scattering. The results show that the hydrodynamic diameters of copolymers have no obvious change in each working solution below lower critical solution temperature (LCST); across LCST, the diameters increased suddenly at different initial temperature in various aqueous solutions; above LCST, they decreased slightly as the temperature increased in UHQ water, and increased continuously with increasing temperature or salt concentration in saline solutions, and reduced with the rising of pH value in pH buffer. These are attributed to different intermolecular and intramolecular forces leading to disparity in dimension, conformation, and LCST of copolymers. The hydrogen bonding between water molecules and copolymer chains could maintain size and conformation of copolymer single chain; the hydrogen bonding between amide linkages and hydrophobic interactions between isopropyl groups result in intramolecular collapse and intermolecular aggregation; the electrostatic repulsion weakens aggregation extent of copolymers. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013