Interpenetrating polymer networks of poly(2,6-dimethyl-1,4 phenylene oxide) and poly(urethane acrylate). II

The synthesis and characterization of full interpenetrating polymer networks (IPNs) of poly(2,6-dimethyl-1,4 phenylene oxide) (PPO) and poly(urethane acrylate) (PUA) using ethylenediamine as the crosslinker for the PPO and styrene-divinyl benzene as the crosslinking agent for the PUA is described. The resulting IPNs are single phase at all compositions (80, 60, 50, and 40 wt.% PPO). The stress/strain data reveal a maximum at the 20 wt.% PUA composition and a fairly weak minimum at the 60 wt.% PUA composition. Previous measurements suggest that at this maximum the interpenetration of the constituent networks is at a maximum for these compositions. The maximum in tensile strength exhibited at the 20 wt.% composition PUA is significantly higher than that of the constituent networks. In general, as expected, the glass transition temperatures, ultimate strength data, etc., are essentially the same as those found for IPNs in which the PPO was crosslinked with hexamethylene diamine. 8 ref.--AA