Toughening modification of (Acrylonitrile-styrene-acrylic copolymer)/(α-Methylstyrene-acrylonitrile copolymer) binary blend via using different impact modifiers

In this work, different impact modifiers such as acrylic resin impact modifier, chlorinated polyethylene (CPE), nitrile rubber, powdered nitrile rubber, and hydrogenated nitrile rubber, were chosen to improve the toughness of (acrylonitrile-styrene-acrylic copolymer)/(α-methylstyrene-acrylonitrile copolymer) (ASA/α-MSAN) binary blend. The blend ratios of the ASA/(α-MSAN)/(impact modifier) ternary system were 30/70/20 and 70/30/20 by mass, respectively. The results showed that the impact strength significantly increased, nearly 30 times (22.59 kJ·m⁻², 22.26 kJ·m⁻², and 25.24 kJ·m⁻²) compared with that of control samples (0.80 kJ·m⁻²) when nitrile rubber, powdered nitrile rubber, or hydrogenated nitrile rubber was added to the ASA/(α-MSAN) (30/70) matrix, respectively. Moreover, the impact strength of ASA/(α-MSAN) (70/30) was dramatically enhanced to 46 kJ·m⁻² with the addition of 20 parts by weight per hundred parts of resin of chlorinated polyethylene. The toughness of ASA/(α-MSAN) with or without impact modifiers was also characterized via fracture energy calculated from stress-strain curves. The results were perfectly consistent with that of impact strength. The results of dynamic mechanical analysis demonstrated the existence of α-MSAN (glass transition temperature at approximately 140°C). The heat distortion temperature was barely changed, indicating the addition of impact modifiers barely affects the heat resistance. J. VINYL ADDIT. TECHNOL., 22:326–335, 2016.