Separation and Characterization of Block and Graft Copolymers by Thin-Layer Chromatography

Abstract

Abstract Feasibilities of thin-layer chromatography (TLC) and its combination with gel permeation chromatography in characterization of block and graft copolymers are discussed. The simplest application of TLC is to test the purity of block and graft samples having been subjected to purification treatment. TLC allows further to determine the compositional heterogeneity of block copolymers without interference of molecular weight, and to distinguish block samples by the difference in block sequence even on the same composition level. The latter applicability is illustrated for styrene-butadiene copolymers with different chain architecture. Finally two applications of TLC as a tool for characterization of graft systems are described: one is to isolate side-chain polymers truely grafted on mother polymer chains, and the other to isolate true graft copolymers from reaction products.