Phase behavior and interactions in blends of poly[(butylene adipate)-co-poly(butylene terephthalate)] copolyester with poly(4-vinyl phenol)

摘要

Miscibility with a linear T_g-composition relationship was proven for blend of poly(butylene adipate-co-butylene terephthalate) [P(BA-co-BT)] with poly(4-vinyl phenol) (PVPh). In comparison to the blends of PBA/PVPh and poly(butylene terephthalate) (PBT)/PVPh, the Kwei's T_g model fitting on data for the P(BA-co-BT)/PVPh blend yields a q value between those for the PBA/PVPh and PBT/ PVPh blends. The q values suggest that the interaction strength in the P(BA-co-BT)/PVPh blend is not as strong as that in the PBT/PVPh blend. Upon mixing the PVPh into the immiscible blend of PBA and PBT, the ternary PBA/ PBT/PVPh blends only exhibits partial miscibility. Full-scale ternary miscibility in whole compositions is not possible owing to the significant Δχ effect (χ_(ij)-χ_(ik)). The wavenumber shifts of the hydroxyl IR absorbance band indicates that the H-bonding strength is in decreasing order-PBT/PVPh > P(BA-co-BT)/PVPh > PBA/PVPh- and shows that the BA segment in the copolymer tends to defray interactions between P(BA-co-BT) and PVPh in blends.