Ethyl aluminum sesquichloride

Using a solution process, the choice of catalyst system is determined, among other things, by the nature of the third monomer and factors such as the width of the mol wt distribution to be realised in the product. A number of articles review the induence of catalyst systems on the stmctural features of the products obtained (3,5—7). The catalyst comprises two main components first, a transition-metal haHde, such as TiCl, VCl, VOCl, etc, of which VOCl is the most widely used second, a metal alkyl component such as (C2H )2A1C1 diethylalurninum chloride, or monoethyl aluminum dichloride, (C2H )AlCl2, or most commonly a mixture of the two, ie, ethyl aluminum sesquichloride, [(C2H )2Al2Cl2]. 

Most recent work is in accord with mechanism (b). In an effort to distinguish these mechanisms studies on model propagating species have been carried out.IS6 liW For S-MMA polymerization initiated by AIBMe- -13C (Scheme 8.13) it has been established by end group analysis that extremely small amounts of ethyl aluminum sesquichloride (<10 3M with 1.75 M monomers) are sufficient to cause a substantial enhancement in specificity for adding S in the initiation step. This result suggests that complexation of the propagating radical may be sufficient to induce alternating copolymerization but does not rule out other hypotheses. 

Aluminum, ichloroethyl-, mixt with chlorodiethyl-aluminum Aluminum, trichlorotriethyidi- EINECS 235-137-7 Ethyl aluminum sesquichloride HSDB 2013 Sesquiethylaluminum chloride ... 

Ethyl aluminum sesquichloride Methylcyclopentadlenyl manganese 1612 237-335-9 4-((4-Morpholinylthio)thioxomethyi)- morpholine 2582... 

Alternating Copolymers. The reactivity of polar monomers, e.g. acrylonitrile, methyl methacrylate or maleic anhydride can be enhanced by com-plexing them with a metal halide e.g., zinc or vanadium chloride) or an organo-aluminum halide (ethyl aluminum sesquichloride). These complexed monomers participate in a one-electron transfer reaction with either an uncom-plexed monomer or another electron-donor monomer, e.g. olefin, diene, or styrene, forming alternating copolymers with free-radical initiators. 

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