Specific interactions in binary and ternary blends of poly(vinyl chloride) with poly(methyl methacrylate- co-acrylic acid) and poly( n-butyl methacrylate- co-4-vinylpyridine)

Abstract

The miscibility of binary blends of poly(methyl methacrylate- co-acrylic acid) (MMAA) with poly( n-butyl methacrylate- co-4-vinylpyridine) (BM4VP) and of ternary blends of each of these copolymers with poly(vinyl chloride) (PVC) has been studied by Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). As a result of specific interactions of various strengths, BM4VP-26 (containing 26 mol% of 4-vinylpyridine) was found to be miscible with PVC and with MMAA-22 (containing 22 mol% of acrylic acid), while MMAA copolymers were immiscible in all proportions with PVC. There are two possible BM4VP sites for hydrogen bonding to either MMAA or PVC. This copolymer was then used to solubilize the PVC and MMAA in ternary PVC/MMAA/BM4VP blends. This effect was also studied by FTIR spectroscopy and DSC. The results indicate that ternary blends containing an equal amount of PVC and MMAA-22 and more than 50% by weight of BM4VP-26 are miscible.