MISCIBILITY AND SPECIFIC INTERACTIONS IN BLENDS OF POLY(2-ETHYL-2-OXAZOLINE) WITH HYDROXYLATED POLYMETHACRYLATES

The compatibility of blends of poly(2-ethyl-2-oxazoline) (PEOX) with p oly(2-hydroxy-ethyl methacrylate) (PHEMA) and poly(2-hydroxypropyl met hacrylate) (PHPMA) was investigated by means of differential thermal a nalysis and infrared spectroscopy. Calorimetric results show single gl ass transition temperatures in the entire range of compositions for bo th systems. S-shaped curves are obtained when plotting the glass trans ition temperatures vs. blend compositions. IR analysis of blends revea ls the existence of specific interactions via hydrogen bonding between the carbonyl and hydroxyl groups of PHEMA and PHPMA. The association phenomena were quantitatively studied from room temperature up to 180 degrees C with the aid of spectral subtraction techniques.