Calorimetric Study of Gradient Block-copolymers of Poly(butylacrylate) and Poly(methylmethacrylate)
Abstract
The miscibility and phase separation in the diblock (AB) and triblock (ABA) copolymers consisting of poly(butyl acrylate) (block B) and gradient copolymers of butyl acrylate and methyl methacrylate (block A) were investigated by means of conventional DSC as a function of the composition of the blocks A. In all copolymers studied, both blocks are presented by two separate glass transition temperatures. The low-temperature transition corresponds to devitrification of block B and is independent of composition and temperature is close to that of pure poly(butyl acrylate), while the higher transition corresponds to glass transition of the copolymeric block A, which decreases and broadens with increasing methylmethacrylate content in block A. The immiscible polymers are connected by chemical bonds, so that the mobilities of the phases influence each other. Shifts in the glass transition temperature and the broadening of the transitions as well as their asymmetry are discussed. --- Supported by NSF, Polymers Program, DMR-9703692, and the Div. of Mat. Sci., BES, DOE at ORNL, managed by UT-Batelle, LLC, for the U.S. Department of Energy, under contract number DOE-AC05-00OR22725.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2002
- Bibcode:
- 2002APS..MARB33022B