TUNABLE HIGH GLASS-TRANSITION ELECTRO-OPTICAL POLYMERS BY RING OPENING METATHESIS POLYMERIZATION

2E-O properties arise from the non-centrosymmetric alignment of non-linear optical (NLO) chromophores during application of an electric field. One of the challenges in preparing materials for practical applications involves preventing decay of the poling-induced order during device operation. 3 This can be achieved by incorporating the E-O chromophores into high glass-transition (Tg) polymers either as a guest or by covalent attachment. Covalent attachment is generally preferred as the motion of the chromophores is more restricted and phase separation from the matrix is not an issue. 4 Many of the materials prepared in this regard require either demanding reaction conditions unsuitable for the E-O chromophores, post-polymerization modification or are not easily processed. 5,6 Preparation of thermally stable EO materials via direct polymerization of chromophore containing monomers under mild reaction conditions is highly desirable. Ring opening metathesis polymerization (ROMP) is an attractive alternative to other modes of polymerization because well-defined, high molecular weight polymers can be obtained under mild reaction conditions with excellent functional group tolerance. 7 Thus ROMP would be a viable route to directly produce E-O polymers where the desired chromophore is incompatible with other polymerization methods. Herein, we report the synthesis of tunable high Tg EO polymers by ROMP. Experimental General Methods and Materials. All solvents and reagents were purchased from Aldrich and used as received. Compounds 2, 3, 4, 4(dimethylamino) pyridinium 4-toluene sulfonate (DPTS) and cis-5norbornene-exo-2,3-carboxylic anhydride were prepared according to the literature.