Influence of composition on properties of nylon 6/EVOH blends

In this work, the relationships between composition and properties of Ny6/E VOH system were examined by means of several techniques and the results wer e interpreted in terms of level of compatibility. Blends of different ratio n of Ny6 and EVOH have been processed in a laboratory-based film blowing ex trusion apparatus. Rheological measurements, FTIR and morphological analysi s, and thermal and mechanical properties were carried out. Peculiar rheolog ical, thermal, and mechanical behaviors were observed for the blend contain ing 25% by weight of EVOH. At this composition, FTIR analysis has pointed o ut that a minimum in molecular motion is achieved as a consequence of a max imum interaction of the polar groups (amide group if Ny6 and hydroxyl group s of EVOH) involved. Moreover, gas permeability measurements on the blown f ilms have been performed at T = 30 degrees C. (C) 1999 John Wiley & Sons, I nc.