摘要
合成了三(4-异丙基芳氧基)稀土[Ln(OPIP)3],并用于催化ε-己内酯开环聚合。研究结果表明,在不同稀土元素的化合物中,三(4-异丙基芳氧基)镧[La(OPIP)3]具有较高的催化活性,在非极性溶剂中,ε-己内酯的转化率和聚己内酯的分子量较高。La(OPIP)3催化ε-己内酯聚合的适宜条件为:ε-已内酯浓度为2.5 mol·L-1,n(ε-己内酯):n(La)=1 000,60℃,60 min,甲苯作溶剂。在此条件下,聚己内酯的数均分子量为11.40×104,分子量分布为1.31。利用1HNMR分析聚合物端基表明,该反应按"配位-插入"机理进行。
Rare earth tris(4-isopropylphenolate)s [ Ln (OPIP)3 ] was synthesized and used as the catalyst for ring-opening polymerization of e-caprolactone. The results indicated that rare earth tris (4-iso- propylphenolate)s doped with lanthanum [La( OPIP)3 ] exhibited higher activity in non-polar solvents, with higher monomer conversion and higher molecular weight of palycaprolactone. The optimum condition for ring-opening polymerization of e-caprolactone over lanthanum tris(4-isopropylphenolate)s was as follows : e-caprolactone concentration 2.5 mol · L - 1, n (e-caprolactone) : n (La) = 1 000,60 ℃, 60 rain, toluene as the solvent. Number-average molecular weight of 11.40 × 104 and molecular weight distribution of 1.31 for polycaprolactone was obtained under the optimum condition. 1 HNMR analysis indicated that mechanism for the polymerization over lanthanum tris (4-isopropylphenolate) followed a monomer inserting into the growing chains and acyl-oxygen bond scission path.
出处
《工业催化》
CAS
2009年第12期63-67,共5页
Industrial Catalysis
关键词
催化化学
三(4-异丙基芳氧基)稀土
Ε-己内酯
开环聚合
catalytic chemistry
rare earth tris (4-isopropylphenolate) s
ε-caprolactone
ring-openingpolymerization