Second order non-linear optical interpenetrating polymer networks based onpolyurethane or poly(methyl methacrylate) and epoxy polymer

Two interpenetrating polymer networks (IPNs), tone pseudo-IPN consisting of a linear polyurethane/epoxy-based polymer network and one full-IPN consist ing of a poly(methyl methacrylate)/epoxy-based polymer network) have been s ynthesized and characterized. Both IPNs showed only one T-g; hence a homoge neous phase morphology is suggested. The second-order non-linear optical co efficients (d(33)) of the pseudo-IPN and the full-IPN were measured and fou nd to be 2.78 x 10(-7) esu and 1.86 x 10(7) esu, respectively. The study of temporal stability at room temperature and elevated temperature (120 degre es C) indicates that the full-IPN is more efficient at improving the orient ational stability of the non-linear optical chromophores than the pseudo-IP N, because of the permanent entanglements of the two component networks in the full-IPN. (C) 1999 Society of Chemical Industry.