Lg. Parada et al., MISCIBILITY IN BLENDS OF POLY(VINYL ACETATE-CO-VINYL ALCOHOL) WITH POLY(N,N-DIMETHYLACRYLAMIDE), Polymer, 39(5), 1998, pp. 1019-1024
Miscibility of poly(N,N-dimethylacrylamide) (PDMA) with poly(vinyl ace
tate) (PVAC), poly(vinyl alcohol) (PVAL) and poly(vinyl acetate-co-vin
yl alcohol) (ACAL copolymers) has been investigated over a wide compos
ition range. Differential scanning calorimetry (DSC) results indicate
that PDMA is immiscible with PVAC, but is miscible with PVAL and ACAL
copolymers in certain range of compositions. The ACAL/PDMA phase diagr
am for different copolymer compositions has been determined. The varia
tion of the glass transition temperature with blend composition for mi
scible systems was found to follow the Kwei equation. Infrared spectro
scopy studies of blends reveal the existence of specific interactions
via hydrogen bonding between hydroxyl groups in vinyl alcohol units an
d the carbonyl group in the tertiary amide, which appear to be decisiv
e for miscibility. (C) 1997 Published by Elsevier Science Ltd. All rig
hts reserved.