Synthesis And Character Of Double-side Acrylate Liquid Crystallines Used In Brightness Enhancement Film

Liquid crystals used in brightness enhancement film, is a new style function materials in these years. Double-side acrylate liquid crystallines with good photo-electricity performance is one important materials of BEF. It has good application potentiality in the field of information storage and mixed liquid crystals. Two double-side chain liquid crystal acrylates, one with three carbon spacers and the other with four carbon spacers, were prepared in different processes.In the first process, liquid crystal double-side acrylate with three carbon alkoxy chain was synthesized, which is divided into three steps: firstly, 4-(3-Hydroxypropoxy) benzoic acid was made by p-hydroxybenzoic acid with 3-Chloropropanol, and the flexible spaces were added into p-hydroxybenzoic acid; secondly, 4-(3-Acryloyl oxypropyloxy) benzoic acid was produced by the product with acryloyl chloride; thirdly, it was esterificated with o-hydroquinone in the DCC and DMAP-catalyzed, in order to generate the double-side acrylate liquid crystal with three carbon alkoxy chain mesogenic unit.In the second process, liquid crystal double-side acrylate with four carbon alkoxy chain was synthesized, which is divided into three steps: firstly, 4-Chlorobutyl acetate was made by Tetrahydrofuran and Acetic chloride with ZnCl2 as a catalyst; sencondly, the synthesis of 4-(4-Hydroxybutoxy) benzoic acid as mesogenic unit, was produced by 4-Chlorobutyl acetate with ethyl p-hydroxybenzoate in DMF, then hydrolysis under alkaline condition, and acidification with hydrochloric acid; secondly, 4-(4-Acryloyl oxybutoxy) benzoic acid was produced by the product with acryloyl chloride; thirdly, it was esterificated with o-hydroquinone in the DCC and DMAP-catalyzed, in order to generate the double-side acrylate liquid crystal with three carbon alkoxy chain mesogenic unit.Result of performance measurement of the two double-side acrylate liquid crystallines by melting point apparatus,IR and DSC shows that they are of perfect liquid crystal performance, the two are all nematic liquid crystals, and their liquid crystal performance is very stable.