Facile synthesis,high thermal stability,and unique optical properties of hyperbranched polyarylenes

摘要

New hyperbranched polyarylenes of high molecular weights are synthesized in high yields by copolycyclotrimerizations of diynes 1,4-diethynylbenzene,4,4'-diethynylbiphenyl,2,7-diethynylfluorene and 2,5-diethynylthiophene with monoynes 1-heptyne,1-octyne and 1-dodecyne catalyzed by TaCl_5-Ph_4Sn in toluene.All the polymers show good solubility in common organic solvents,possess excellent thermal stability,and emit strong deep-blue lights of~400 nm with quantum efficiencies up to 98%.The polyarylenes effectively limit 532 nm lasers light,some of which show optical limiting performances superior to that of C_(60),a well-known optical limiter.