Changes in the interfacial properties of PC/SAN blends with compatibilizer

Abstract

Block copolymers of polycarbonate-b-poly-(methyl methacrylate) (PC-b-PMMA) and tetramethyl poly-(carbonate)-b-poly(methyl methacrylate) (TMPC-b-PMMA) were examined as compatibilizers for blends of polycarbonate (PC) with styrene-co-acrylonitrile (SAN) copolymer. To explore the effects of block copolymers on the compatibility of PC/SAN blends, the average diameter of the dispersed particles in the blend was measured with an image analyzer, and the interfacial properties of the blends were analyzed with an imbedded fiber retraction (IFR) technique and an asymmetric double cantilever beam fracture test. The average diameter of dispersed particles and interfacial tension of the PC/SAN blends were reduced by adding compatibilizer to the PC/SAN blends. Fracture toughness of the blends was also improved by enhancing interfacial adhesion with compatibilizer. TMPC-b-PMMA copolymer was more effective than PC-b-PMMA copolymer as a compatibilizer for the PC/SAN blends.

Polycarbonate/acrylonitrile–styrene–acrylic elastomer terpolymer blends with enhanced interfacial adhesion and surface gloss

“…The procedure for the synthesis of TMPC-b-PMMA has been described in detail elsewhere. 14,15 Blends of PC with the SAN copolymer were prepared via melt mixing or solution casting. PC/SAN mixtures were mixed in a Haake Rheomix torque rheometer (Karlsruhe, Germany) for 15 min at 60 rpm and 240°C.…”

“…In this study, PMMA was also explored as an interfacial agent for PC/SAN blends, and the results were compared with those of the TMPC-b-PMMA block copolymer, which was the most efficient compatibilizer of the block copolymers examined previously. 15 PC does not form a miscible blend with PMMA when both components have high molecular weights. However, PC and PMMA do form a miscible blend of the molecular weight of one or both components is reduced because of the small positive interaction energy, that is, 0.03 cal/cm 3 .…”

“…The application of blends with phase-separated structures is often limited because of their poor adhesion at the weld. [11][12][13][14][15] Other problems stem from the physical (or chemical) aging of butadiene rubber. Butadiene rubber, containing a double bond in its repeat unit, undergoes physical (or chemical) aging caused by ultraviolet (UV) radiation in outdoor applications.…”

“…In previous studies, 14,15 we explored block copolymers, such as PC-b-PMMA [where PMMA is poly(methyl methacrylate)], PC-b-SAN, TMPC-b-PMMA (where TMPC is tetramethyl polycarbonate), and TMPC-b-SAN, as interfacial agents for PC/SAN blends. In this study, PMMA was also explored as an interfacial agent for PC/SAN blends, and the results were compared with those of the TMPC-b-PMMA block copolymer, which was the most efficient compatibilizer of the block copolymers examined previously.…”

“…However, the AN content of the SAN copolymer was fixed at approximately 24 wt % because the PC/ SAN blend exhibited maximum interfacial adhesion at this AN concentration. 14,15 To enhance the surface gloss of the blend, we controlled the particle size of the rubber, the rubber shape, the viscosity ratio of PC to ASA, and the type of compatibilizer and its concentration.…”