Filler effect on formation and properties of reinforced interpenetrating polymer networks

The formation processes of unfilled and filled interpenetrating polymer net works (IPNs) and some of their physico-mechanical properties have been inve stigated. The formation kinetics and constituent network curing rates deter mine the rate and degree of microphase separation, This in turn determines the boundary layer composition and structure. Introduction of filler into t he IPN during formation affects greatly the crosslinking reaction and the m icrophase segregation of homopolymers. It has been shown that the degree of phase segregation in filled IPNs differs from that in unfilled ones. All t he fillers were found to shorten the time of internal stress appearance and to increase its value for IPNs with predominantly high-modulus component c ontent. Some filled IPNs were shown to have greater thermodynamic stability than unfilled ones.