Antioxidant Emulsion And Coagulation Processing Application In ABS Polymer

Acrylonitrile-Butadiene-Styrene terpolymer (ABS) is a widely used enginnering thermo-plastic due to its good overall performance. However, ABS is easy to be degraded when suffering from external influence like heat, stress and so on. Because ABS resin contains rubber phase (butadiene) which has unsaturated double bond, so discoloration and mechanical property decreasing will happen. In this work, first we evaluated different kinds antioxidant emulsions properties which were made from different kinds of sufactants. At same time, we dosed these antioxidant emulsions into latex during coagulation processing and come to High Rubber Grafted-ABS (HRG-ABS). Only one kinds of coagulant was used during this period. We compared these HRG-ABS properties via thermol stability evaluations. Secondly, sevral kinds of coagulants were tried in producing HRG-ABS powder. In the part, only one kinds of antioxidant emulsion was used. These HRG-ABS with different coagulants were also evaluated by thermol stability testings. Through a series of experiments, we got the general idea for HRG-ABS thermol stability stabilization. This research could be a reference for the ABS industries choosing antioxidants and coagulants.Firstly, sodium oleate, potassium oleate, sodium stearate, potassium stearate and rosin soap were used as emulsifiers for preparing antioxidant emulsions. Paticle Size Distribution, pH value, viscosity, solid content, emulsion stability and Zeta potential were tested. The conclusion is that potassium oleate can be a suitable surfactant for making antioxidant (Wingstay L and DLTDP) emulsion. It’s no need to be added defoamer agent and thickener and can get appropriate particle size, narrow particle size distribution and good antioxidant emulsion stability. At same time, these antioxidant emulsions were applied into ABS latex. One kinds of coagulant was used into coagulation process. After HRG-ABS was prepared, GC, OIT, oven aging and dynamic stove aging were tested. It proved that compared to free antioxidant ABS, thermol stability of HRG-ABS with antioxidant was effectively improved. Emulsion type antioxidant was more evenly dispersed in HRG-ABS than powder type antioxidant. This also can help to improve the thermol stability of HRG-ABS. What’s more, after comparison, we learned that antioxidant emulsion made from potassium oleate not only contains good overall properties, but also can produce HRG-ABS containing more stable thermol stability. Secondly, five kinds of coagulants were applied in coagulation process, like hydrochloric acid, sulfuric acid, phosphoric acid, calcium chloride and magnesium sulfate. Same dosage of antioxidant emulsion made from potassium oleate was added into ABS latex. After HRG-ABS was prepared, GC, OIT, oven aging and dynamic stove aging were also evaluated. The results shew that using acid as coagulant was more helpful than salt as a coagulant for improving thermol stability of HRG-ABS. And phosphoric acid is more efficiant than hydrochloric acid and sulfate. On the other hand, salt as coagulant contributed better performance than that of acid in therms of HRG-ABS initial color. And magnesium sulphate as coagulant shew better result than that of calcium chloride.