Effect of PS Blends on Microstructure of PIPSPLA Thin Film

Polystyrene (PS) homopolymer and polyisoprenepolystyrenepolylactide (PIPSPLA) triblock copolymer were blended at certain mole ratios for preparing thin films, and the microstructures of thin film samples were investigated by AFM. Results showed that when n(PS)∶n(PIPSPLA) was 1∶2 and 1∶1, ordered cylinders appeared and the dimension of the cylinders were different from that of the unblended PIPSPLA thin film. When n(PS)∶n(PIPSPLA) was 2∶1, microislands of PS appeared, due to the segregation of PS chain from the PIPSPLA molecular chain.