Influence of Chain architecture on high-pressure copolymer solution behavior: Experiments and modeling

Abstract

Publisher Summary This chapter describes the influence of chain architecture on high-pressure copolymer solution behavior. Phase behavior studies with poly(ethylene- co -methyl acrylate), poly (ethylene- co -butyl acrylate), poly(ethylene- co -acrylic acid), and poly(ethylene- co -methacrylic acid) are performed in the normal alkanes, their olefinic analogs, dimethyl ether, chlorodifluoromethane, and carbon dioxide up to 250 o C and 2,700 bar. The backbone architecture of the copolymers and the solvent quality greatly influences the solution behavior in supercritical fluids. As the amount of polar units in the backbone architecture is increased, copolymer–copolymer polar interactions increase and high temperatures are required to dissolve the copolymer in nonpolar solvents. If the copolymer has a comonomer capable of hydrogen bonding, the solubility in alkane and alkene solvents is dramatically reduced at lower temperatures, where copolymer–copolymer hydrogen bonding is much stronger than other intermolecular interactions. The solubility of copolymers greatly increases in the solvents that hydrogen bond with the copolymer. In addition, the solubility of a copolymer depends on the temperature that attenuates the specific interactions.