Reactive blending of commercial PET and PC with freshly added catalysts

Reactive blending of commercial poly(ethylene terephthalate) (PET) and bisphenol A polycarbonate (PC), with catalysts added in the form of powder dispersed on the polymers just before melt mixing, was performed in a Brabender Plasticord 2000 apparatus at 275 degrees C. Catalytic activity of the catalysts freshly added to polymers was found to be much higher as compared with that of the residues of the same type of catalysts remaining in PET after its synthesis. Furthermore, the catalytic activity appeared to be strongly dependent on the structure of the ligand that influences the catalyst solubility in the polymer melt. N.m.r. spectroscopy, selective degradation of PC fragments, solubility tests in methylene chloride and d.s.c. measurements made it possible to range the catalysts studied according to their catalytic activity. Copyrigh

PET/PC blends and copolymers by one-step extrusion .1. Chemical structure and physical properties of 50/50 blends

Reactive blending of poly(ethylene terephthalate) (PET) and bisphenol A polycarbonate (PC) with a catalyst mechanically dispersed on polymers was performed by one-step extrusion for about 1 min at 275 degrees C. The product appeared to be a transparent amorphous plastic with a single glass transition temperature. This approach provides a possibility to produce PET/PC block copolymers directly by extrusion of homopolymers or to create their compatible blends during one-step extrusion by varying the type and concentration of the catalyst. Copyrigh