Acrylate Rubber Solution Polymerization Legal Research

Acrylate rubber (ACM) molecular chain belongs to saturated carbon chain, and the second carbon atom contains the polar ester group. The special structure gives many excellent characters of ACM, such as heat, aging, oil, and ozone resistance. ACM shows much better mechanical properties and processing performance than fluorine rubber and silicone rubber, and much better heat, oil and oxygen aging performance than nitrile rubber, which is widely used in the automotive industry in recent years. According to the literature so far, the preparation of ACM with high concentration solution polymerization method had not been found. In the present paper, batch solution polymerization method was used to prepare ACM and the influence of polymerization conditions on the reaction and product properties was investigated. The aim of this paper is to find the optimum conditions of ACM preparation and try to set up the theory foundation for the continuous polymerization of ACM.In this paper, butyl acrylate (BA) was used as the major monomer, benzoyl peroxide (BPO) as initiator, glycidyl methacrylate (GMA) as the curing point of monomer, methyl acrylate (MA) and ethyl acrylate (EA) as comonomers, toluene and ethyl acetate as solvents. The effect of polymerization temperature, initiator concentration, monomer concentration and solvent types on the polymerization rate, monomer conversion and solution viscosity were studied. At the same time, the molecular weight and molecular weight distribution, cross-linking degree, structure and thermal stability of ACM were measured.When toluene was used as solvent, result showed the reaction rate of polymerization improved with the increase of BPO and when the concentration of BPO was beyond 0.08%, the difference between the conversion was not obvious. The increase of temperature was beneficial to the improvement of reactive rate, and the difference between the conversion was not obvious when the temperature beyond 70℃. The reactive rate and conversion increased with the monomer concentration.When ethyl acetate was used as solvent, result showed the reaction rate increased with the BPO content. When the concentration of BPO was higher than 0.15%, the change of reaction rate was not obvious and the difference between the monomer conversion was small. The reaction rate increased with the temperature and the difference between the monomer conversion was small when the temperature was beyond 70℃and the reaction showed maximum conversion when the temperature was 60℃。The introduction of comonomers induced the decrease of monomer conversion and had no obvious influence on the reaction rate. The monomer conversion had no marked change when the copolymerization ratio was modified.The properties of ACM product were measured. The crosslinking test showed that crosslinking could take place during the heat treatment with the increase of MA content and the crosslinking degree increased with the temperature. ACM with maximum molecular weight of 1.99×106 and molecular weight distribution of 1.05 was obtained which showed better character than the product of Dupont and Japan. NMR test showed the constitution of the ACM copolymer was consistent with the rate of charge when the MA content was lower 40%, otherwise, the constitution deviated form the rate of charge.