Homopolymerization of 4-vinyl pyridine（4-VP） and copolymerization of 4-VP with styrene（St） were performed by catalyst systems composed of calix[4]arene-neodymium complex 2,di-n-butylmagnesium and hexamethyl phosph...Homopolymerization of 4-vinyl pyridine（4-VP） and copolymerization of 4-VP with styrene（St） were performed by catalyst systems composed of calix[4]arene-neodymium complex 2,di-n-butylmagnesium and hexamethyl phosphoramide. The molecular weight of P（4-VP） was greatly affected by adding calix[4]arene-neodymium complex,and high molecular weight of P（4-VP） was got by using calix[4]arene-neodymium complex.The highest molecular weight of P（4-VP） was as high as 4.65×106 obtained by using a catalyst system with 2.0×10-4?mol/L of calix[4]arene-neodymium complex,while the molecular weight of P（4-VP） was only 5.62×105 without calix[4]arene-neodymium complex. In addition,4-VP-St copolymers with different 4-VP contents were obtained in good yield.When styrene was polymerized first for a time period,and then 4-VP was added,4-VP-St copolymers with 4.85?mol%～23.3?mol% of 4-VP units were obtained,but when 4-VP and styrene were added at the same time the resultant 4-VP-St copolymers had 44.0?mol%～66.3?mol% of 4-VP units.展开更多
To obtain a novel support with practical value for metallocene catalyst(\%η\%\|C\-5H\-5)TiCl\-3(CpTiCl\-3), poly(styrene\|co\|4\|vinylpyridine)/SiO\-2 nanoscale hybrid material(SrP/SiO\-2) was firstly produced as sup...To obtain a novel support with practical value for metallocene catalyst(\%η\%\|C\-5H\-5)TiCl\-3(CpTiCl\-3), poly(styrene\|co\|4\|vinylpyridine)/SiO\-2 nanoscale hybrid material(SrP/SiO\-2) was firstly produced as support. After pretreatment by methylaluminoxane(MAO), the hybrid materials reacted with CpTiCl\-3. The results from SAXS, SEM and TEM indicated the morphology and structure of organic/inorganic hybrid materials, and the size of inorganic particle in hybrid was nanoscale. The results from IR and XPS showed that there were two possible cationic active species in the hybrid\|supported catalyst, the polymerization results of styrene proved this possibility.展开更多
文摘Homopolymerization of 4-vinyl pyridine（4-VP） and copolymerization of 4-VP with styrene（St） were performed by catalyst systems composed of calix[4]arene-neodymium complex 2,di-n-butylmagnesium and hexamethyl phosphoramide. The molecular weight of P（4-VP） was greatly affected by adding calix[4]arene-neodymium complex,and high molecular weight of P（4-VP） was got by using calix[4]arene-neodymium complex.The highest molecular weight of P（4-VP） was as high as 4.65×106 obtained by using a catalyst system with 2.0×10-4?mol/L of calix[4]arene-neodymium complex,while the molecular weight of P（4-VP） was only 5.62×105 without calix[4]arene-neodymium complex. In addition,4-VP-St copolymers with different 4-VP contents were obtained in good yield.When styrene was polymerized first for a time period,and then 4-VP was added,4-VP-St copolymers with 4.85?mol%～23.3?mol% of 4-VP units were obtained,but when 4-VP and styrene were added at the same time the resultant 4-VP-St copolymers had 44.0?mol%～66.3?mol% of 4-VP units.
文摘To obtain a novel support with practical value for metallocene catalyst(\%η\%\|C\-5H\-5)TiCl\-3(CpTiCl\-3), poly(styrene\|co\|4\|vinylpyridine)/SiO\-2 nanoscale hybrid material(SrP/SiO\-2) was firstly produced as support. After pretreatment by methylaluminoxane(MAO), the hybrid materials reacted with CpTiCl\-3. The results from SAXS, SEM and TEM indicated the morphology and structure of organic/inorganic hybrid materials, and the size of inorganic particle in hybrid was nanoscale. The results from IR and XPS showed that there were two possible cationic active species in the hybrid\|supported catalyst, the polymerization results of styrene proved this possibility.
基金supported by the National Natural Science Foundation of China(21773215,J1210060)the Innovative Research Grant for Undergraduate Students of National/Zhengzhou University(201710459008)~~
