MISCIBILITY AND SPECIFIC INTERACTIONS IN BLENDS OF POLY(HYDROXY METHACRYLATES) WITH POLY(VINYLPYRIDINES)

Poly(4-vinylpyridine) and poly(2-vinylpyridine) were found to be misci ble with poly(2-hydroxyethyl methacrylate) and poly(3-hydroxypropyl me thacrylate). This miscibility is proved by calorimetric studies in con junction with infrared analysis of the blends. All blends show a singl e glass transition which is of a higher value than the glass transitio ns of the blends calculated on the basis of additive behavior. Further more, the variation of the glass transitions of the blends follows the Jenckel-Heusch equation. Infrared studies show that carbonyl, hydroxy l, and pyridine ring peaks undergo important changes which were attrib uted to hydrogen bonding between the hydroxyl groups in both methacryl ates and the basic nitrogen atom present within the pyridine ring. The se interactions were observed to be of greater relevance for poly(4-vi nylpyridine) than for poly(2-vinylpyridine). Finally, phase transition s were also studied. No phase separation was found for blends having p oly(4-vinylpyridine), whereas blends including poly(2-vinylpyridine) s how a low critical solution temperature at 140-175-degrees-C.