SIDE-CHAIN CRYSTALLIZATION INDUCED IN AMORPHOUS POLYMERS BY CHARGE-TRANSFER INTERACTION

It is shown that crystallization of side-chains of amorphous polymers can be induced by charge-transfer interaction. This is illustrated for the 1:1 D/A blend of the donor poly[4-(9-carbazolyl)butyl methacrylat e] with the low molecular crystalline rod-like biacceptor 4,4'-di(brom obutoxy)-3,3',5,5'-tetranitrobiphenyl. It is supposed that the charge- transfer interaction results in a self assembling in the 1:1 D/A blend between the low molecular biacceptor and the donor carbazoyl side gro ups, discoupled by alkyl spacers from the amorphous methacrylic backbo ne. The crystallization in the D/A blend is illustrated by optical mic roscopy, DSC and by the WAXS, the latter confirming the new crystallin e structure of the 1:1 D/A blend, different from the crystalline struc ture of the low molecular biacceptor. Comparative molecular simulation of the most probable conformation of respective 10 repeating units in dicates an extension of the backbone in the D/A blend, expressed by an substantial increase of the end-to-end distance. At the same time the tendency for a helicoidal arrangement and stacking of the D/A complex ed side-groups is suggested by the simulation, using the amorphous bui lder modul of Cerius(2) 1.5.