Synthesis of graft copolymer and compatibilization of polycarbonate/polystyrene blend

Abstract

This thesis was studied about compatibilization of Polycarbobnate (PC)/Polystyrene (PS) blend. Two kinds of compatibilization methods for the immiscible PC/PS blend were suggested and investigated the effect of compatibilization. First part of thesis is devoted to the reactive compatibilization using reactive components. Anhydride terminated PC (PC-anh) was prepared from the polymerization by a conventional condensation polymerization reactor with vacuum. The formation of PC-anh was examined by FT-IR and NMR technique. On the other hand, oxazoline containing PS (RPS) in the PS phase was chosen as a counterpart functional group. Torque observation and FT-IR spectroscopy confirm that the reaction between PC-anh and RPS occurs. These reactive components were introduced when PC/PS was blended as a reactive compatibilizer. Fine morphologies were successively observed with addition of these components. Izod impact strength, tensile strength and elongation enhanced accordingly as the reactive components increased. Rheological properties were also measured. At the low frequency, plateau moduli increased with increasing amount of reactive components. Interfacial tension was predicted using by Palierne emulsion model. Predicted interfacial tension value was lowered with increasing amount of reactive components. The second part of the thesis is concerning a new compatibilizer for PC/PS blend. The PBT/RPS graft copolymer was prepared through melt blending in order to test the compatibilizing capability in PC/PS blend. FT-IR analysis revealed the formation of such graft copolymer. Very fine morphologies were observed with the increasing amount of this compatibilizer. Izod impact strength was also improved with addition of this compatibilizer. Rheological properties were measured for these blends. At around 1 rad/sec frequency, pronounced elasticity appeared with addition of compatibilizer. Interfacial tension for these blends was predicted by using Palierne emulsion model....