process for the preparation of a polymer of a diene combines through polymerization in solution using a idrocar billitio as well as a triidrocar bilboro in catalytic system

摘要

1411579 Mixed organometallic compounds in diene polymerization SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ BV 22 Dec 1972 [21 Jan 1972] 59303/72 Heading C3P Conjugated dienes are polymerized using a mixture of a lithium hydrocarbon and a trihydrocarbyl boron compound in a liquid solvent for the catalyst components and for the resulting polymer, the catalyst components suitably being in part in the form of a complex with a conjugated diene or alkenyl aromatic hydrocarbon, and the following concentration criteria being obeyed, where Li(f) and B(f) are the final concentrations of the lithium and boron in gramatom/litre, the former concentration reduced by the quantity of lithium compound necessary to complex with all the initial contaminants in the monomer feed, and Li(c) is the quantity of lithium compound added to compensate for at least part of the lithium compound deactivated during polymerization. The concentration criteria are: Li(f)-Li(c) is between 10SP-5/SP and 10-1 g. at/1., B(f) : Li(f) is above 0.01 and below 1-00, Li(f)-Li(c)-B(f) is from 0.5.10SP-5/SP to 10.10SP-5/SP and B(f) : Li(f)-Li(c) is higher than 0.5. In examples isoprene or butadiene are polymerized in a C 5 alkane/alkene mixture and isooctane or a mixture of cyclohexane and nhexane, using sec-C 4 H 9 Li/B(C 2 H 5 ) 3 catalysts under the specified concentration conditions and in some cases with di-ethyl adipate coupling of the product.