Preparation And Properties Of PA6/ABS Blends Used For Automotive

In this work the impact of formulae and process methods on mechanical properties, odour, anti-aging property, anti-scrape property and as well as dimensional stability of polyamide6/acrylonitrile butadiene styrene (PA6/ABS) was investigated. Through the formulation, process optimization, the blends which can satisfy the usage for automotive trim was successfully produced.Comparing mechanical properties, we draw the conclusion that the optimum injection temperature and the mold temperature were 240℃and 80℃, respectively. It is found that Styrene maleic anhydride copolymer (SMA) with the content of 22% maleic anhydride (MA) was good compatibilizer for the PA6/ABS blends. The hindered phenol 1098 and phosphite S-9228 mixture (content of 0.2 and 0.3 per, respectively) gave the blends excellent anti-oxidation performance. After 5 times extrusion the yellowing index was only 26.0. With respect to the selection of base resin, it was found that PA6 with viscosity of 2.5 gave composite good mechanical properties. With the increase of molecular weight of ABS powder, the mechanical strength and heat resistance were improved. The higher of the rubber content, the better of the impact property was achived. For a blend of PA6/ABS/SMA=65/29/6, the brittle-ductile transition took place at the rubber content of 15.7%-17.4%. Impact strength and Vicat softening temperature of the blends could satify the requirements of automotive interior material at the PA6 content of 30%-75%.The odor study of the blends showed that a longer lead screw combination, higher extrusion temperatures, and a higher degree of vacuum, the better of the odor performance. The blends showed improved toughness and odor property when partially replaced emulsion polymerized ABS with the bimodal distribution bulk polymerized ABS.When UV absorber Tinuvin 234 and the light stabilizer Chimassorb 119 mixed together at a ratio of 0.25/0.25, the best long-term light stability would achieve. Replaced ABS in PA6/ABS blends with the ASA or AES, which has no double bond in the macromolecular chain, the weathering resistance of alloy significantly enhanced. The weatherability of alloy was improved with added inorganic toner such as titanium dioxide, nickel titanate yellow or carbon black. Among these inorganic toners, the carbon black was the most effective one.