FUNCTIONAL-GROUP ACCESSIBILITY IN HYDROGEN-BONDED POLYMER BLENDS .2. MISCIBILITY MAP OF 2,3-DIMETHYLBUTADIENE-STAT-VINYLPHENOL BLENDS WITH ETHYLENE-STAT-VINYL ACETATE

An experimental miscibility map for 2,3-dimethylbutadiene-stat-4-vinyl phenol (DMBVPh) blends with ethylene-stat-vinyl acetate (EVA) is obtai ned and compared to theoretical calculations. The number of hydrogen-b onded carbonyl groups in these systems is measured by FTIR spectroscop y and some systematic trends are apparent. It is shown that the miscib ility of DMBVPh/EVA blends is much more sensitive to the difference in solubility parameters than to the degree of hydrogen bonding. However , the contribution from hydrogen bonding in these mixtures is importan t and is significantly influenced by screening effects. A simple corre lation for the dependence of the screening effect on the average spaci ng of functional groups in a chain is proposed and tested.