Homo-and copolymerization of vinylcyclohexane with α-olefins in the presence of heterogeneous and homogeneous catalytic systems

Nucleation of Polypropylene Homo- and Copolymers

“…PVCH is known to be a very effective polymeric nucleating agent (Alcazar et al, 2006;Rishina et al, 2006) and can be synthesized in-situ on catalysts for the polymerization of isotactic PP (Vestberg and Leskinen, 2002), resulting in a fine dispersion in the polymer and very high nucleating activity even at lowest concentrations. Kaminsky et al (2006) demonstrated that nano-silica, MWNTs and PCC can be finely dispersed by in-situ polymerization when using these particles as catalyst support for metallocene activated with MAO.…”

Activation of rac‐Me2Si(ind)2ZrCl2 by Methylalumoxane Modified by Aluminum Alkyls: An EPR Spin‐Probe, 1H NMR, and Polymerization Study

“…Our polymerization data are in good agreement with the previous results on the effect of TIBA on the polymerization activity of various zirconocene/MAO systems. [13][14][15][16][17][18][19][20] …”

“…[17] The addition of TIBA increases the activity of several homogeneous zirconocene/MAO systems in the copolymerization of propylene with hex-1-ene. [18] For gas-phase ethene polymerization with the catalyst system ( n BuCp) 2 ZrCl 2 /MAO on various organic supports, additions of TIBA gave prolonged catalytic activities; at relatively low [Al] MAO /[Zr] ratios they also led to increased activities. [19] For the catalyst system Me 2 Si(Ind) 2 -ZrCl 2 /MAO on a silica gel support, the addition of TIBA has recently likewise been observed to cause a substantial increase of activities for ethene polymerization.…”

Effect of Different Aluminum Alkyls on the Metallocene/Methylaluminoxane Catalyzed Polymerization of Higher α‐Olefins and Styrene

“…One simple way to reduce the amount of MAO is to replace it partially by aluminum alkyls. [9][10][11][12] Among different trialkylaluminum tested, usually only triisobutylaluminum (TIBA) showed an activating effect in a metallocene/MAO catalytic system, whereas trimethylaluminum (TMA) or triethylaluminum (TEA) usually have a deactivating effect. [9][10][11]13,14] Normally, the addition of TIBA to the polymerization system leads to an increase in the molecular weight of the obtained polymers, while TMA or TEA decreases M n .…”

“…[9][10][11][12] Among different trialkylaluminum tested, usually only triisobutylaluminum (TIBA) showed an activating effect in a metallocene/MAO catalytic system, whereas trimethylaluminum (TMA) or triethylaluminum (TEA) usually have a deactivating effect. [9][10][11]13,14] Normally, the addition of TIBA to the polymerization system leads to an increase in the molecular weight of the obtained polymers, while TMA or TEA decreases M n . [10,14] The replacement of MAO by different aluminum alkyls in the polymerization of higher a-olefins catalyzed by rac-EtInd 2 ZrCl 2 and rac-(CH 3 ) 2 CInd 2 ZrCl 2 and in the syndiospecific polymerization of styrene with CpTiCl 3 as a catalyst was studied.…”