Effect of block sequence on responsive behavior of core-shell diblock polymer brushes
writer：Cao, Lan; Chen, Kaimin; Qin, Xue; Zhang, Ying; Li, Kai; Guo, Xuhong
keywords：nanoparticles, structural, stimulus-response
source：期刊
specific source：Materials Letters, 2018, 223(13), 116-119
Issue time：2018年
In this work, two kinds of core-shell diblock polymer brushes, i.e., poly(acrylic acid)-b-poly(N-isopropylacrylamide) and poly(N-isopropylacrylamide)-b-poly(acrylic acid) diblock polymer brushes with polystyrene cores (PSV@PAA-b-PNIPA and PSV@PNIPA-b-PAA), were prepared by surface-initiated photoiniferter-mediated polymerization (SI-PIMP). Both of them are demonstrated to be dually responsive to pH and temperature. Compared to brushes with random polymer chains of PAA and PNIPA, the control of PAA and PNIPA block sequence not only affects the responsive behavior, but also changes the competition between intermolecular and intramolecular forces which results in remarkable conformation variation. The “inverse” temperature response of PSV@PAA-b-PNIPA could shine light on structure design of polymer brushes for applications such as protein separation.