Morphology and Properties of Model Block and Graft Copolymers

摘要

For this project a number of new polymer materials were synthesized including trifunctional, tetrafunctional and hexafunctional regular graft copolymers. Additionally, a range of poly(cyclohexadiene) (PCHD) homopolymers and block copolymers containing PCHD blocks were prepared. The morphologies of the regular graft copolymers, and PCHD containing block copolymers were determined by TEM and SAXS. Additionally, the morphologies of cyclic block copolymers were studied and compared to their linear analogs. The tensile mechanical properties of the regular multigraft materials were studied and related to molecular architecture. It was found that increasing junction point functionality and increasing number of junction points per molecule increased strength and toughness, and decreased hysterysis. A series of block double graft (BDG) copolymers of unique molecular architecture were studied to relate molecular architecture to morphology and mechanical properties. The mechanical properties of some BDG materials compared favorably to commercial thermoplastic elastomers.