The ring-opening polymerization of 1,4-dioxan-2-one （PDO） was carried out by lanthanum tris（2,6-di-tert-butyl-4- methylphenolate） （La（OAr）3） as novel single component initiaLor. The influences of polymerizatio...The ring-opening polymerization of 1,4-dioxan-2-one （PDO） was carried out by lanthanum tris（2,6-di-tert-butyl-4- methylphenolate） （La（OAr）3） as novel single component initiaLor. The influences of polymerization reaction temperature and the molar ratio of monomer to initiator on the monomer conversion and molecular weight of poly（1,4-dioxan-2-one） （PPDO） were explored. PPDO with high viscosity average molecular weight of 1.95×10^5 can be prepared at 40℃ when [PDO]/ [La（OAr）3] molar ratio was 800. Mechanism investigation shows that the polymerization proceeds through a ＂coordination- insertion＂ mechanism with selective rupture of acyl-oxygen be,nd of PDO.展开更多
The polymerization of n-hexyl isocyanate(HNCO) was carried out in the presence of a novel single initiator, rare earth tris(2,6-di-tert-butyl-4-methylphenolate)[Ln(OAr)_3]. The influences of reaction conditions such a...The polymerization of n-hexyl isocyanate(HNCO) was carried out in the presence of a novel single initiator, rare earth tris(2,6-di-tert-butyl-4-methylphenolate)[Ln(OAr)_3]. The influences of reaction conditions such as the monomer concentration, the polymerization temperature and time, and the types of solvents on the polymerization of HNCO were studied. Polymerizations of phenyl, i-propyl, p-tolyl, n-butyl and n-octyl isocyanates with La(OAr)_3 were also examined.展开更多
Phenyl isocyanate was for the first time successfully polymerized by divalent samarium complex (ArO)2Sm(THF)4. The monomer concentration and temperatur affected the polymerization greatly.
The ring opening polymerization of 2,2-dimethyltrimethylene carbonate (DTC) initiated by single component of tris(2,6-di-tert-butyl-4-methylphenoxo) lanthanide (Ln(OAr)(3)) is reported. The initiators are highly activ...The ring opening polymerization of 2,2-dimethyltrimethylene carbonate (DTC) initiated by single component of tris(2,6-di-tert-butyl-4-methylphenoxo) lanthanide (Ln(OAr)(3)) is reported. The initiators are highly active to the polymerization and give high molecular weight polymers. (HNMR)-H-1 spectra and DSC measurement suggest the polymerization is free of decarboxylation. Mechanism study shows that the monomer insertion is via the break of acyl-oxygen bond of DTC.展开更多
A green and highly efficient strategy for the preparation of bridged spirocyclic compounds via visible-light-induced cyclization of 2-(2-(arylethynyl)benzylidene)malononitrile derivatives with 2,6-di(tert-butyl)-4-met...A green and highly efficient strategy for the preparation of bridged spirocyclic compounds via visible-light-induced cyclization of 2-(2-(arylethynyl)benzylidene)malononitrile derivatives with 2,6-di(tert-butyl)-4-methylphenol(BHT)at room temperature was developed.The photoinduced radical reactions generated the corresponding products in good yields under simple and mild reaction conditions.展开更多
探究了抗氧化剂的种类、抗氧化剂2,6-二叔丁基-4-甲基苯酚(BHT)的用量及其添加方式对乙烯-醋酸乙烯共聚物(EVA )/线型低密度聚乙烯(LLDPE)硅烷交联材料的接枝率、吸光比( R )、耐热性能和力学性能的影响。结果表明,不同的抗氧化剂会降低...探究了抗氧化剂的种类、抗氧化剂2,6-二叔丁基-4-甲基苯酚(BHT)的用量及其添加方式对乙烯-醋酸乙烯共聚物(EVA )/线型低密度聚乙烯(LLDPE)硅烷交联材料的接枝率、吸光比( R )、耐热性能和力学性能的影响。结果表明,不同的抗氧化剂会降低EVA/LLDPE硅烷交联材料的吸光比和维卡软化温度,但提高其拉伸强度和断裂伸长率。适量的BHT能较好保持EVA/LLDPE硅烷交联材料的性能,当BHT用量为0.22%,吸光比和拉伸强度最大,而且把BHT添加到B料中,使得样品各项性能保持最佳。展开更多
基金This work was financially supported by the financial support of National Natural Science Foundation of China (No. 20434020)
文摘The ring-opening polymerization of 1,4-dioxan-2-one （PDO） was carried out by lanthanum tris（2,6-di-tert-butyl-4- methylphenolate） （La（OAr）3） as novel single component initiaLor. The influences of polymerization reaction temperature and the molar ratio of monomer to initiator on the monomer conversion and molecular weight of poly（1,4-dioxan-2-one） （PPDO） were explored. PPDO with high viscosity average molecular weight of 1.95×10^5 can be prepared at 40℃ when [PDO]/ [La（OAr）3] molar ratio was 800. Mechanism investigation shows that the polymerization proceeds through a ＂coordination- insertion＂ mechanism with selective rupture of acyl-oxygen be,nd of PDO.
文摘The polymerization of n-hexyl isocyanate(HNCO) was carried out in the presence of a novel single initiator, rare earth tris(2,6-di-tert-butyl-4-methylphenolate)[Ln(OAr)_3]. The influences of reaction conditions such as the monomer concentration, the polymerization temperature and time, and the types of solvents on the polymerization of HNCO were studied. Polymerizations of phenyl, i-propyl, p-tolyl, n-butyl and n-octyl isocyanates with La(OAr)_3 were also examined.
文摘Phenyl isocyanate was for the first time successfully polymerized by divalent samarium complex (ArO)2Sm(THF)4. The monomer concentration and temperatur affected the polymerization greatly.
文摘The ring opening polymerization of 2,2-dimethyltrimethylene carbonate (DTC) initiated by single component of tris(2,6-di-tert-butyl-4-methylphenoxo) lanthanide (Ln(OAr)(3)) is reported. The initiators are highly active to the polymerization and give high molecular weight polymers. (HNMR)-H-1 spectra and DSC measurement suggest the polymerization is free of decarboxylation. Mechanism study shows that the monomer insertion is via the break of acyl-oxygen bond of DTC.
基金the National Natural Science Foundation of China (No. 22071171)the Natural Science Foundation of Zhejiang Province (No. LZ22B020003)
文摘A green and highly efficient strategy for the preparation of bridged spirocyclic compounds via visible-light-induced cyclization of 2-(2-(arylethynyl)benzylidene)malononitrile derivatives with 2,6-di(tert-butyl)-4-methylphenol(BHT)at room temperature was developed.The photoinduced radical reactions generated the corresponding products in good yields under simple and mild reaction conditions.
文摘探究了抗氧化剂的种类、抗氧化剂2,6-二叔丁基-4-甲基苯酚(BHT)的用量及其添加方式对乙烯-醋酸乙烯共聚物(EVA )/线型低密度聚乙烯(LLDPE)硅烷交联材料的接枝率、吸光比( R )、耐热性能和力学性能的影响。结果表明,不同的抗氧化剂会降低EVA/LLDPE硅烷交联材料的吸光比和维卡软化温度,但提高其拉伸强度和断裂伸长率。适量的BHT能较好保持EVA/LLDPE硅烷交联材料的性能,当BHT用量为0.22%,吸光比和拉伸强度最大,而且把BHT添加到B料中,使得样品各项性能保持最佳。
