Copolymerization of ethylene with propylene and higher α-olefins catalyzed by (imido)vanadium(iv) dichloride complexes

Abstract

We have synthesized and characterized a series of (imido)V(iv) complexes bearing different imido groups and coligands, to be used, in combination with an aluminum alkyl, as catalysts for the (co)polymerization of ethylene with propylene.

Semibatch Terpolymerization of Ethylene, Propylene, and 5-Ethylidene-2-norbornene: Heterogeneous High-Ethylene EPDM Thermoplastic Elastomers

“…40 All the investigated catalysts show a preference for incorporating ENB to propylene, which is consistent with the fact that they are more active in the ethylene copolymerization with cyclic olefins, 36 than with α-olefins. 35 The comonomer incorporation was affected by the ligand set: it increases in the order 1a (P = 2.5 mol%; ENB = 5.0 mol%) « 2a (P = 6.4 mol%; ENB = 10.0 mol%) < 2b (P = 6.5 mol%; ENB = 13.2 mol%), the effect of coligand being dominant over the effect of imido substituents.…”

“…These catalytic systems are derived from a combination of vanadium compounds (e.g., VCl 4 , VOCl 3 , VO(OR) 3 , V(acac) 3 , R = alkyl group, acac = acetylacetonate) and alkyl aluminum halide (typically Et 2 AlCl) or aluminum hydride derivatives, and a Lewis base (e.g., anisole). 29−34 Herein, we report the terpolymerization of ethylene with propylene and ENB catalyzed by known imido vanadium(IV) complexes, 35,36 differing in the ligand substitution, in combination with Et 2 AlCl and Cl 3 CCO 2 Et (ETA). The polymerizations have been carried out in a semi-batch mode where ethylene is continuously supplied to the polymerization mixture and its pressure is kept constant, while liquid propylene and ENB are added only at the beginning.…”

Progress in vanadium complex catalysts and their catalytic behavior toward copolymerization of ethylene with &alpha;-olefins

“…27(图4) [45] , 配合物27/Et 3 Al 2 Cl 3 催化体系催化乙烯与丙 烯共聚(Al/V = 50, P/E = 5, T = 30°C, t = 20 min)的催 . 在助催化剂Et 3 Al 2 Cl 3 作用下, 图4所示的含V=N双 键的亚胺钒(IV)配合物28~32催化乙烯与丙烯共聚(助 催化剂: Et 2 AlCl, Al/V = 500, ETA/V = 10, P/E = 4, T = 20°C), 催化活性为400~2100 kg mol -1 h -1 [46] . 在P/E单体 摩尔比为4时, 共聚产物中丙烯结构单元含量仅为4.2% [46] .…”

“…在助催化剂Et 3 Al 2 Cl 3 作用下, 图4所示的含V=N双 键的亚胺钒(IV)配合物28~32催化乙烯与丙烯共聚(助 催化剂: Et 2 AlCl, Al/V = 500, ETA/V = 10, P/E = 4, T = 20°C), 催化活性为400~2100 kg mol -1 h -1 [46] . 在P/E单体 摩尔比为4时, 共聚产物中丙烯结构单元含量仅为4.2% [46] . 钒(IV)配合 物29~31也可以催化乙烯与1-辛烯共聚(助催化剂: Al/V = 500, ETA/V = 10, 1-辛烯/E = 4, T = 20°C, t = 2~4 min), 催化活性在840~1160 kg mol -1 h -1 范围内, 得到的共聚 物中1-辛烯结构单元含量为6.5%(mol)~9.0%(mol), M w 为64~97 kg mol -1 , PDI为2.1~2.6 [46] .…”

SSA fractionation of thermoplastic polyurethanes

“…[5] Such size distribution can be estimated, in some cases, e.g., multiblock copolymers. [6] In the case of polyolefins, in which the SSA technique has been widely used, the SSA has been recently used to perform branching analysis [7,8] and photodegradation studies, [9] among others. Besides the application of the SSA on polyolefins, the SSA can also be employed for elucidating the impact on the layer/lamellar thickness distribution of additives, grafted fillers or even other components within a particular polymer matrix, such as in the case of lignin inclusion within a polycaprolactone matrix, [10] and in blends, [11] respectively.…”