Abstract We demonstrated that the dimeric 1- tert -butyl-2,2,4,4,4-pentakis(dimethylamino)-2Λ 5 , 4Λ 5 -catenadi(phosphazene) supported on polystyrene ( PS- t -BuP 2 ) was an efficient and recyclable catalyst for the ring-opening polymerization (ROP) of δ -valerolactone ( δ -VL). The heterogeneous catalyst PS- t -BuP 2 could be recycled and reused for five consecutive cycles without significant decrease of catalytic activity. The monomer conversions maintained between 79% and 85% for five cycles. Using BnOH as initiator, the produced polyvalerolactones (PVLs) had controlled molecular weights (MWs) and narrow MW distributions ( Đ ), and the products were free of catalyst by simple filtration. The 1 H NMR and MALDI-TOF characterizations of the obtained PVLs clearly indicated the presence of the initiator residue at the chain end.

中文翻译：

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聚苯乙烯珠负载磷腈超强碱作为可回收有机催化剂用于 δ-戊内酯的开环聚合

摘要 我们证明了负载在聚苯乙烯上的二聚体 1-叔丁基-2,2,4,4,4-pentakis(二甲氨基)-2Λ 5 , 4Λ 5 -catenadi(phosphazene) (PS-t-BuP 2 ) 是一种用于δ-戊内酯（δ-VL）开环聚合（ROP）的高效且可回收的催化剂。多相催化剂PS-t-BuP 2 可以回收并重复使用五个连续循环而催化活性没有显着降低。单体转化率在五个循环中保持在 79% 和 85% 之间。使用 BnOH 作为引发剂，生产的聚戊内酯 (PVL) 具有可控的分子量 (MW) 和窄的 MW 分布 (Đ)，并且通过简单的过滤，产物不含催化剂。所得 PVL 的 1 H NMR 和 MALDI-TOF 表征清楚地表明链端存在引发剂残基。