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The molecular chain of the acrylic rubber is a saturated carbon chain, and containing polar ester group on the second carbon atom at the same time, this special structure given its many excellent characteristics such as heat resistance, aging resistance, oil resistance, and resistance to ozone, UV resistance and other properties, and mechanical properties and processing performance than fluorine rubber and silicone rubber, heat resistance, oil resistance and aging properties superior to nitrile rubber is widely used in the automotive industry and other fields, in recent years, the automotive industry focused on promotion rubber material. The far high concentration solution polymerization method to prepare acrylic rubber studies have not been reported. Therefore, this paper take intermittent the solution polymerization synthesis process, the investigated polymerization conditions change the polymerization reaction, the product of nature, to seek the best test recipes, and lay the theoretical foundation for the ultimate realization of continuous solution polymerization of acrylate rubber. In this experiment, the butyl acrylate (BA) based monomer, benzoyl peroxide (BPO) initiator, and glycidyl methacrylate (GMA) as the cure site monomer, acrylic acid, methyl (MA), acrylic acid ethyl acrylate (EA) as the comonomer, toluene, ethyl acetate as solvent, and by changing the polymerization temperature, initiator concentration, the polymerized monomer concentration and the kind of solvent, and other factors investigated on the polymerization rate of the solution, the monomer conversion, the viscosity of the polymerization system and the molecular weight of the acrylate rubber (ACM) and the molecular weight distribution of the width of the impact, while the degree of crosslinking of the ACM, internal structure and thermal stability to do the appropriate test. The results are found in the use of toluene as the experiment of a solvent, the polymerization rate with the lead to the increase of the amount of the agent BPO significantly improved, BPO concentration higher than 0.08% after the monomer conversion rate is not very different; monomer polymerization rate increased rapidly with increases in temperature. monomer conversion, after the temperature reached 70 ° C the difference is small; increase in monomer concentration conducive to the improvement of the polymerization rate and conversion. With ethyl acetate as the solvent, we found that the polymerization rate over BPO content increased with the increase after BPO concentrations above 0.15%, the polymerization rate changes little, the monomer conversion ratio is not very different; monomer polymerization rate increases in temperature and rapid increase in the monomer conversion rate difference is small after the temperature reached 70 ° C, 60 ° C, the highest rate of monomer conversion; comonomer causes the monomer conversion rate, little effect on the polymerization rate of polymerization of methyl acrylate (MA) slightly better than the ethyl acrylate (EA); percentage change comonomer experimental results, the increased percentage methacrylate monomer conversion. ACM rubber prepared to conduct the performance test. The crosslinking test results show that during the heat treatment with the increase of the MA content of the ACM, ACM prone crosslinked, the degree of crosslinking with the temperature increase; this experiment ACM a molecular weight of up to 1,990,000, the distribution width of 1.05, in U.S. DuPont emulsion products, Japanese solution polymerization ACM indicators; thermal gravimetric analysis results showed that, ACM of MA introduced to cause the thermal decomposition temperature is increased, the improved heat resistance; NMR test results showed that the the MA monomer content of 0%, 20%, 30% BA and MA copolymerization composition and the feed ratio consistent, when the comonomer is increased to 40%, the copolymerization composition of the deviation occurs.
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