Poly(ethyl Acrylate) and Poly(Gamma-Benzyl-L-Glutamate): An Interpenetrating Polymer System

摘要

The rigid rod polymer poly(gamma-benzyl-L-glutamate) (PBLG) dissolves in ethyl acrylate (EA) at elevated temperatures. Upon cooling to room temperature, a gel is formed. Phase separation occurs on a submicron level. The PBLG forms a continuous submicron network. The sample is homogeneous to the eye. With the addition of an initiator to the EA, the vinyl monomer may be polymerized to form poly(ethyl acrylate) (PEA). When the polymerization initiated by photochemical initiator occurs from the EA-PBLG gel state, no gross change in the PBLG network occurs. A polymer film of linear PEA and PBLG is formed. With the addition of an initiator and crosslinker to the EA, EA may be crosslinked upon polymerization from the EA-PBLG gel state. An interpenetrating polymer network (IPN) of crosslinked PEA and PBLG is formed. Rheologically, the storage and loss moduli variations due to changes in frequency, strain, and PBLG concentration are examined for each type of sample. Additionally, the effects of crosslinker concentration is examined for IPN's. The characteristics of the PEA made in the laboratory are compared to commercial PEA samples by nuclear magnetic resonance (NMR) spectroscopy and gel permeation chromatography (GPC). The swelling and leaching traits of the PEA-PBLG samples are investigated using methanol. Methanol is a good solvent for PEA but a non-solvent for PBLG. (aw)