Linear low density polyethylene from ethylene as an o nly monomer was prepared by the combination catalyst system of Et(Ind) 2ZrCl 2 an d {2 [2 Me 4 Br C 6H 3NC(Me)] 2C 5H 3N}FeCl 2 activated with methy laluminoxane (...Linear low density polyethylene from ethylene as an o nly monomer was prepared by the combination catalyst system of Et(Ind) 2ZrCl 2 an d {2 [2 Me 4 Br C 6H 3NC(Me)] 2C 5H 3N}FeCl 2 activated with methy laluminoxane (MAO).The two catalysts were well matched in a single reactor and i t was observed that the “comonomer effect" appeared in the in situ copolymeriz ation of ethylene.The comonomer effect was some strongly influenced by the molar ratio of Al to (Fe+Zr) and the polymerization temperatures.At 60℃ and n(Al )/n(Fe+Zr)=2000,the maximum activity of the catalytic system(8 5×10\+6g/mo l·h) was 4\^25 times higher than that of homopolymerization of ethylene(2\^0×1 0\+6g/mol·h),and the value of n(Fe)/n(Zr) was 0 5.At n(Al)/n(F e+Zr)=1000,the maximum activity diminished.When polymerization temperatures incr eased,the maximum activity of the in situ copolymerization decreased and the co rresponding ratio of Fe to Zr also decayed.The copolymers made from this catalyt ic system had the characteristics of low melting point(from 132 34℃ to 70 97 ℃),low density(from 0 9467?g/cm\+3 to 0\^9283?g/cm\+3) and narrow molecular weight distribution(from 2\^29 to 1\^86).However,it’s no obvious influence of th e comonomer effect on the physical properties of the copolymers.展开更多
Reaction of the β diketimine compound (2,6 Me 2C 6H 3)NC(Me)CHC(Me)N(C 6H 3 2,6 Me 2)H (LH,1) with 1 equiv of n BuLi/hexane in THF,followed by crystallization from toluene,affords the β diketiminate lithium complex ...Reaction of the β diketimine compound (2,6 Me 2C 6H 3)NC(Me)CHC(Me)N(C 6H 3 2,6 Me 2)H (LH,1) with 1 equiv of n BuLi/hexane in THF,followed by crystallization from toluene,affords the β diketiminate lithium complex LLi(THF)(2)in high yields.The crystal structure of complex 2 was determined by X ray diffraction method.It crystallizes in monoclinic,space group P 2/(1)/ n with a =1 4036(5), b =1 3261(4), c =1 4248(5)nm, β =115 437(6)°, V =2 3950(13)nm 3,and D c =1 066Mg·m -3 for Z =4.In the structure,the metallacycle is almost fully planar,and the Li atom is coordinated by two nitrogen atoms of the β diketiminate ligand and one oxygen atom of THF molecule.展开更多
选用芴基胺基二甲基钛配合物为主催化剂,在改性烷基铝氧烷(MMAO)和2,6-二异丙基苯酚(BHT)的活化下,进行了乙烯与1-十二烯的共聚。结果表明:芴基上引入叔丁基、胺基上引入金刚烷基的芴基氨基二甲基钛配合物对乙烯/1-十二烯的共聚表现出...选用芴基胺基二甲基钛配合物为主催化剂,在改性烷基铝氧烷(MMAO)和2,6-二异丙基苯酚(BHT)的活化下,进行了乙烯与1-十二烯的共聚。结果表明:芴基上引入叔丁基、胺基上引入金刚烷基的芴基氨基二甲基钛配合物对乙烯/1-十二烯的共聚表现出高活性;共聚活性随着Al与Ti物质的量比的增大逐渐上升,当Al与Ti物质的量比为1000时,达到最高活性,为2600 kg Polymer/(mol Ti·h),所得共聚物的重均分子质量最高达到2.7×10~6g/mol,当1-十二烯添加量为6.8 mmol时,共聚物中1-十二烯的插入率达到0.34%,此时共聚物的熔点为124.6℃。展开更多
文摘Linear low density polyethylene from ethylene as an o nly monomer was prepared by the combination catalyst system of Et(Ind) 2ZrCl 2 an d {2 [2 Me 4 Br C 6H 3NC(Me)] 2C 5H 3N}FeCl 2 activated with methy laluminoxane (MAO).The two catalysts were well matched in a single reactor and i t was observed that the “comonomer effect" appeared in the in situ copolymeriz ation of ethylene.The comonomer effect was some strongly influenced by the molar ratio of Al to (Fe+Zr) and the polymerization temperatures.At 60℃ and n(Al )/n(Fe+Zr)=2000,the maximum activity of the catalytic system(8 5×10\+6g/mo l·h) was 4\^25 times higher than that of homopolymerization of ethylene(2\^0×1 0\+6g/mol·h),and the value of n(Fe)/n(Zr) was 0 5.At n(Al)/n(F e+Zr)=1000,the maximum activity diminished.When polymerization temperatures incr eased,the maximum activity of the in situ copolymerization decreased and the co rresponding ratio of Fe to Zr also decayed.The copolymers made from this catalyt ic system had the characteristics of low melting point(from 132 34℃ to 70 97 ℃),low density(from 0 9467?g/cm\+3 to 0\^9283?g/cm\+3) and narrow molecular weight distribution(from 2\^29 to 1\^86).However,it’s no obvious influence of th e comonomer effect on the physical properties of the copolymers.
文摘Reaction of the β diketimine compound (2,6 Me 2C 6H 3)NC(Me)CHC(Me)N(C 6H 3 2,6 Me 2)H (LH,1) with 1 equiv of n BuLi/hexane in THF,followed by crystallization from toluene,affords the β diketiminate lithium complex LLi(THF)(2)in high yields.The crystal structure of complex 2 was determined by X ray diffraction method.It crystallizes in monoclinic,space group P 2/(1)/ n with a =1 4036(5), b =1 3261(4), c =1 4248(5)nm, β =115 437(6)°, V =2 3950(13)nm 3,and D c =1 066Mg·m -3 for Z =4.In the structure,the metallacycle is almost fully planar,and the Li atom is coordinated by two nitrogen atoms of the β diketiminate ligand and one oxygen atom of THF molecule.
文摘选用芴基胺基二甲基钛配合物为主催化剂,在改性烷基铝氧烷(MMAO)和2,6-二异丙基苯酚(BHT)的活化下,进行了乙烯与1-十二烯的共聚。结果表明:芴基上引入叔丁基、胺基上引入金刚烷基的芴基氨基二甲基钛配合物对乙烯/1-十二烯的共聚表现出高活性;共聚活性随着Al与Ti物质的量比的增大逐渐上升,当Al与Ti物质的量比为1000时,达到最高活性,为2600 kg Polymer/(mol Ti·h),所得共聚物的重均分子质量最高达到2.7×10~6g/mol,当1-十二烯添加量为6.8 mmol时,共聚物中1-十二烯的插入率达到0.34%,此时共聚物的熔点为124.6℃。
