Eight xanthates were synthesized to induce living free radical polymerization of vinyl acetate. Four compounds, methyl (4-methoxyphenoxy)carbonothioylsulfanyl acetate, methyl (methoxycarbonothioyl)sulfanyl acetate, methyl (ethoxycarbonothioyl)sulfanyl acetate and methyl (isopropoxycarbonothioyl)sulfanyl acetate were identified as suitable MADIX/RAFT agents, yielding low polydispersity (PDI < 1.2)poly(vinyl acetate) of molecular weights exceeding 5 x 10(4) g.mol(-1). All suitable MADIX/RAFT agents exhibited extended periods of inhibition (0.3 h < t(inh) < 10 h) and moderate rate retardation. The ability of these compounds to control vinyl acetate polymerization can be correlated with the electron density on the central carbon atom of the xanthate. Electrospray ionizaiton mass spectrometric analysis was performed to complete the investigation on the new MADIX/RAFT agents.

中文翻译：

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黄药介导的醋酸乙烯酯活性聚合：MADIX/RAFT 试剂结构的系统变化

合成了八种黄原酸盐以诱导乙酸乙烯酯的活性自由基聚合。四种化合物，甲基（4-甲氧基苯氧基）硫代硫烷基乙酸酯、甲基（甲氧基硫代硫酰）乙酸酯、甲基（乙氧基硫代硫酰）乙酸甲酯和甲基（异丙氧基硫代硫烷基）乙酸酯被确定为合适的 MADIX/RAFT 试剂，产生低多分散性 (PDI < 1.2)poly （醋酸乙烯酯），分子量超过 5 x 10(4) g.mol(-1)。所有合适的 MADIX/RAFT 试剂都表现出延长的抑制期 (0.3 h < t(inh) < 10 h) 和中等速率延迟。这些化合物控制乙酸乙烯酯聚合的能力可以与黄药中心碳原子上的电子密度相关。