Study On Microemulsion Polymerization Of Acrylamide By Combined Initiator System Containing Functional Monomer

Polyacrylamide (PAM) is a functional water-soluble polymer, which is divided into cationic, anionic, amphoteric, non-ionic polyacrylamide. For its good performance on flocculation, sedimentation and thickening, PAM is widely used in water treatment, oil industry, and paper industry, et al.Among verious polymerization systems, the reverse microemulsion solves the problem of the products stability. The reaction rate and water-soluble ability are better than other systems. The combined initiator system, which combines the features of the lower temperature of redox initiator and the higher temperature of azo type initiator, makes the reaction smoothly and reduces the cross-linked of the products. The functional monomer has the dual function to initiate and participate in the reaction. Accordingly, it is conducive to synthesis of higher molecular weight polymer and enhance the degree of polymerization of polymers. For the reason that the factors relevant to the process of polymerization were complicated and unpredictable, thus the new method to predict or optimize the research is one of the means to solve the problems.The neural network was adopted to predict the experiments. Both of the results were very close t. It was showed that the neural network could better reflect the connection between the true value and the predictive value. And the neural network could play an important part in the guidance and forecast the experiments. Furthermore, the experiments and results were proved to be correct and scientific. The neural network applied in fine chemical industry had a good prospect.In this study, the combined-initiator system, which containing (NH4)2S2O8-NaHSO3-AIBN -functional monomer, was used to synthesize PAM. In the inverse microemulsion polymerization, the impact of the functional monomer DMAEMA and DMAPA was researched on the molecular weight of polyacrylamide, as well as different factors of the best experimental conditions. Under different factors, the optimal reaction conditions were obtained by orthogonal experiments. Ultimately, the best reaction conditions could be obtained when AM mass concentration, the temperature of the reaction, the pH of inverse microemulsion, the initiator mass concentration, m functional monomer/ m reductant in redox were 20%,45℃,8.0,0.25%,40% (DMAEMA),and 27%, 40℃, 9.0, 0.30%, 0.1 (DMAPA), respectively.PAM synthesized under the optimal reaction condition was examined by the instrumentality of the molecular, water-solubility, FT-IR, SEM. The molecular weight increased significantly, and the structures were fibrous or blocky-layer. The functional monomer enhanced the water soluble ability of the polymer, and the surface was smoother. The molecular weight of polyacrylamide containing functional monomer DMAEMA and DMAPA was 1.25×10~7 and 1.33×10~7, respectively. Each dissolution time was 6min. The addition of functional monomer DMAPA was more favorable to synthesize polyacrylamide with high molecular weight and water-soluble ability.