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该文合成了一种双官能团的RAFT试剂——S,S’-二(α,α’-二甲基-α″-乙酸)三硫代碳酸酯(BDAT)。以其为链转移剂,在微乳液体系中进行了甲基丙烯酸甲酯的RAFT聚合。分别讨论了聚合反应温度和链转移剂浓度对聚合反应的影响,并对相关的聚合反应动力学常数进行了计算。研究结果表明,在微乳液中进行的RAFT聚合具有显著的活性聚合的特征。聚合产物的相对分子质量(简称分子量,下同)随着转化率的提高而线性增加,同时聚合产物具有较窄的分子量分布,聚合过程随着链转移剂浓度的增加而逐渐可控。另外,利用透射电子显微镜对链转移剂浓度对微乳液粒子尺寸的影响也进行了考察,扫描电镜照片表明,微乳液聚合所得乳液粒子呈现单分散性状态,并且粒子尺寸随着链转移剂浓度的增加而逐渐增加。
In this paper, a bifunctional RAFT reagent, S, S’-bis (α, α’-dimethyl- α "-acetic acid) trithiocarbonate (BDAT) The RAFT polymerization of methyl methacrylate was carried out in the microemulsion system.The effects of polymerization temperature and chain transfer agent concentration on the polymerization reaction were discussed respectively.The kinetic constants of the polymerization reaction were calculated.The results show that, The RAFT polymerization carried out in microemulsion has the characteristic of active polymerization.The relative molecular mass (molecular weight, the same applies hereinafter) of the polymerization product increases linearly with the increase of the conversion, and the polymerization product has a narrower molecular weight distribution. The polymerization The process can be gradually controlled with the increase of the concentration of chain transfer agent.In addition, the effect of chain transfer agent concentration on the particle size of microemulsion was also investigated by transmission electron microscopy. The SEM images show that the emulsion particles obtained by microemulsion polymerization showed single Dispersion state, and the particle size increases gradually with the increase of chain transfer agent concentration.