Conformatoinal changes coupled changes coupled with teh isotropic-anisotropic transition Part 2.Effect of the external orientational field

摘要

A series of poly((sf oplY)-t-butyl acrylate) (S-tBA)copolymers was prepared and characterized. The S-tBA copolymers containing less , , a. 23 mol0/" t-butyl acrylate were fourid to be miscible with poly(2.6-dimethyl-I,4-phenylene oxide) (PPO) at all composition ranges 'ding to differential scanning calorimetry studies. The same S-tBA copolymer series was hydrolyzed and subsequently neutralized toe potassium salts of poly(styrene-ran-acrylic acid). Miscibility of the ionic copolymers with PPO was found to reduce to below ca. , 'mol% of the ionic content. A qualitativeX-ray analysis on the ionic blend indicated that the line of demarcation for incompatibility was :..d to the phenomenon of onset of ion-pair association. Interaction parameter for the above miscible blends was calculated using _Iished semi.empirical relationships. The styrene and tEA moieties were found to have strong "repulsive"type interaction leading to '. i~ ~ven more negative interaction parameter for the S-tEA/PPO blends at higher tEA contents. The combined favorable (S/ppO) and lIIf~vorable (S/tBA) interaction, however. did not improve miscibility for the ionic polymer blends.