Monte Carlo simulation of phase behavior of polymer blends with special interactions

Full Paper: The phase, behavior of A-B-random copolymer/C-homopolymer, blen ds with special interaction was studied by a. Monte, Carlo simulation in tw o dimensions. The interaction between I segment A and segment C was repulsi ve, whereas it was attractive between segment B and segment C. The simulati on results showed that the blend became two large co-continuous phase domai ns at lower segment-B component compositions, indicating that the blend sho wed spinodal decomposition. With an increase of the segment-B component, th e miscibility between the copolymer,and the polymer was gradually improved up to being miscible. In addition, it was found that segment B tended to mo ve to the surface of the copolymer phase in the case of a lower component o f segment B. On the other hand, if was observed that the average, end-to-en d distances ((h) over bar) for both copolymer and polymer changed slowly wi th increasing segment-B component of the copolymer up to 40%, thereafter th ey increased considerably with increasing segment B component. Moreover, it was found that the (h) over bar of the copolymer was obviously shorter tha n that of the homopolymer for the segment-B composition, region from 0% to 80%. Finally, a, phase diagram showing I phase and - II phase regions under the condition of constant-temperature is presented.