Room temperature and low temperature toughness improvement in SAN/ASA blends by blending with CPE, HNBR, and BR

Abstract

Styrene-acrylonitrile copolymer (SAN)/acrylonitrile-styrene-acrylate terpolymer (ASA) blends (75/25, wt/wt) was toughened by blending with impact modifiers including chlorinated polyethylene (CPE), hydrogenated nitrile butadiene rubber (HNBR), and butadiene rubber (BR) and the impact property was tested at four temperatures (-30, 215, 0, and 25 8C). The combination of CPE and HNBR was imported to toughen the SAN/ASA blends, indicating that CPE and HNBR had similar toughening effect at room temperature but HNBR exhibited a better performance at low temperature. When a little HNBR was substituted by BR, the impact strength improved dramatically with the total content of impact modifiers keeping at 30 phr. After 15 phr CPE, 10 phr HNBR and 5 phr BR were employed into blends together, the impact strength reached to a peak of 14 kJ/m 2 at 230 8C while the impact strength of the blends individually toughened by 30 phr CPE or 30 phr HNBR was 5 or 12 kJ/m 2 , respectively. The toughening mechanism showed that the low glass-transition temperature (-108 8C) of BR and the compatibilization between BR and matrix accounted for the improvement of toughness. Simultaneously, scanning electron microscopy, dynamic mechanical analysis, flexural and tensile properties, heat distortion temperature, and Fourier transform infrared spectroscopy were measured. V C 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45364.

Improvement in Low Temperature Izod Impact Strength of SAN/ASA/HNBR Ternary Blends Considering Competing Effects of Glass Transition Temperature and Compatibility

“…Those T g s shift to low temperature about 4°C ~ 5°C than that of pure HNBRs. The same phenomenon has taken place constantly in the system of elastomer toughened polymers . It results from the mismatch of thermal expansion coefficients between elastomer and polymer matrix .…”

“…The peaks at 1,602, 1,495, and 1,454/cm are ascribed to the vibration of benzene skeletal ring, 762 and 702/cm belonging to the single substituted phenyl ring . The bands at 3,060 and 3,030/cm are attributed to the C‐H stretching vibration of H–C=C in phenyl ring . The asymmetric stretching of C–O–C is at 1,165/cm .…”

“…In a previous work, several methods have been devised to enhance the low‐temperature toughness of ASA resin with favorable results. It demonstrated that when 15 phr chlorinated polyethylene (CPE), 10 phr hydrogenated nitrile butadiene rubber (HNBR), and 5 phr butadiene rubber (BR) were used into SAN/ASA (75/25, w/w) blends simultaneously, the Izod impact strength increased from 2 kJ/m 2 to a peak of 14 kJ/m 2 at −30°C .…”