Star‐shaped 1‐vinyl‐2‐pyrrolidone (VP)‐based polymers having four pendant arms were produced via high‐pressure RAFT using the trithiocarbonate‐functionalized core. The use of compression (p = 250 MPa) significantly reduced or eliminated star‐star/star‐chain coupling side reactions and termination process characteristics the for “core‐first” R‐type approach, still allowing for a “pseudo‐living” reaction course up to very high monomer conversion (>98%). Consequently, tailored and highly living star‐shaped poly(1‐vinyl‐2‐pyrrolidone)s (PVP) in a wide range of molecular weights M _n = 2.0–175.6 kg/mol (Đ = 1.18–1.80) have been obtained. The chain extension of the produced polymer was carried out with methyl methacrylate (MMA) via photo‐induced RAFT (λ = 365 nm) in the presence of tertiary amine catalyst, yielding well‐defined amphiphilic star‐shaped block copolymers. DSC measurements showed that synthesized star‐shaped PVP homopolymers revealed much lower glass transition temperature values compared to their commercially supplied linear analogs.

中文翻译：

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基于压力的策略合成基于乙烯基吡咯烷酮的巨星光引发剂。星形嵌段共聚物的途径

使用三硫代碳酸酯官能化的核通过高压RAFT生产具有四个侧链的星形1乙烯基2吡咯烷酮（VP）基聚合物。压缩（p = 250 MPa）的使用显着减少或消除了“核优先” R型方法的星形-星形/星形链偶联副反应和终止过程特征，但仍允许“拟活性”反应当然可以达到很高的单体转化率（> 98％）。因此，定制的高活性星形聚（1-乙烯基-2-吡咯烷酮）（PVP）的分子量范围为M _n = 2.0–175.6 kg / mol（Đ = 1.18–1.80）。在叔胺催化剂的存在下，通过光诱导的RAFT（λ = 365 nm），用甲基丙烯酸甲酯（MMA）进行了聚合物的扩链，生成了定义明确的两亲星形嵌段共聚物。DSC测量表明，合成的星形PVP均聚物与其商业提供的线性类似物相比，玻璃化转变温度值低得多。