MISCIBILITY IN BINARY BLENDS OF POLY(VINYLPHENOL) AND AROMATIC POLYESTERS

The effect of polymer structure on blend miscibility with poly(vinylph enol) (PVPh) has been studied for a variety of polyesters that contain aromatic moieties in their backbone. In general, polyesters derived f rom aliphatic diols showed evidence of interaction and miscibility wit h PVPh. However, immiscibility was observed if the aromatic content of the polyester was very high. Polyesters derived from aromatic-contain ing diols generally showed little interaction and no miscibility with PVPh. Both solution-blending and melt-blending methods were utilized t o prepare the blends. Good correlation between the thermal behavior an d infrared results was observed. Miscibility of PVPh was observed with polyesters consisting of terephthalic acid and a mixture of ethylene glycol and 1,4-cyclohexanedimethanol moieties for copolymer compositio ns; containing at least 20 mol % ethylene glycol. Miscibility was obse rved with poly(ethylene terephthalate), poly(butylene terephthalate), poly(2,2-dimethylpropylene terephthalate), poly(ethylene 2,6-naphthale nedicarboxylate), and a copolymer of terephthalic and pentanedioic aci ds with 1,2-propanediol and glycerol as well as with several cyclic al iphatic copolyesters containing 1,4-cyclohexanedicarboxylic acid. Misc ibility of PVPh was not observed with poly(1,4-cyclohexylene dimethyle ne terephthalate), Ardel D100, Eastman Kodar copolyester A150, several other polyesters with high aromatic content, and two liquid crystalli ne polyesters.