Catalyst and process for the preparation of polyethylenes having a narrow molecular-weight distribution

Claim 2

The catalyst of claim 1 wherein said hydrogen-polysiloxane is methylhydrogenpolysiloxane having a viscosity of from 20 to 40 cSt (25*C).

Claim 3

The catalyst of claim 3 wherein said methylhydrogensiloxane has a viscosity of from 25 to 35 cSt (25*C) and is substantially endblocked with trimethylsilyl groups and has a hydroxy content of from 0.05 to 0.2 pErcent by weight.

Claim 4

The catalyst of claim 3 wherein said component B is a compound selected from the group consisting of 1) esters of halotitanic acids having the formulae TiX''3(OR'''') and TiX''2(OR'''')2 wherein X'' is a halide selected from the group consisting of chlorine and bromine, and R'''' is an alkyl having two to six carbon atoms and 2) mixtures of TiX''4 and Ti(OR'''')4 and 3) mixtures of TiX''4 and TiX(OR'''')3 where X'' and R'''' have the above-assigned values, in such ratios that the amount of OR'''' group is at least 0.7 mols and not more than 2 mols, per mol of titanium.

Claim 5

In a process for the production of polyethylene or modified polyethylene with a narrow molecular-weight distribution which comprises polymerizing monomers selected from the group consisting of ethylene and mixtures of ethylene with up to 10 mol percent of Alpha -olefins having three to eight carbon atoms at a temperature of from 50*C to 120*C and a pressure of from 1 to 100 atmospheres in the presence of a polymerization catalyst prepared from (a) polymeric organo-silicon compounds containing hydrogen bonded to silicon, (b) compounds of heavy metals of the IV to VI sub-groups of the Periodic System, and (c) organo-aluminum compounds, the improvement which consists of utilizing as said polymerization catalyst, the reaction product prepared at a temperature of from -50*C to 100*C of (A) a reaction product prepared at a temperature of from 0* to 120*C of one mol of trialkyl aluminum having from two to eight carbon atoms in each of the alkyls with from one to two mols of a hydrogenpolysiloxane having a viscosity of from 5 to 100 cSt (25*C) and monomer units having the formula

Claim 6

The process of claim 6 wherein said trialkyl aluminum is triethyl aluminum.

Claim 7

The process of claim 6 wherein said hydrogen-polysiloxane is methylhydrogenpolysiloxane having a viscosity of from 20 to 40 cSt (25*C).

Claim 8

The process of claim 6 wherein said methylhydrogensiloxane has a viscosity of from 25 to 35 cSt (25*C) and is substantially endblocked with trimethylsilyl groups and has a hydroxy content of from 0.05 to 0.2 percent by weight.

Claim 9

The process of claim 6 wherein said component B is a compound selected from the group consisting of (1) esters of halotitanic acids having the formulae TiX''3(OR'''') and TiX''2(OR'''')2 wherein X'' is a halide selected from the group consisting of chlorine and bromine, and R'''' is an alkyl having two to six carbon atoms and (2) mixtures of TiX''4 and Ti(OR'''')4 and 3) mixtures of TiX''4 and TiX(OR'''')3 where X'' and R'''' have the above-assiGned values, in such ratios that the amount of OR'''' group is at least 0.7 mols and not more than 2 mols, per mol of titanium.

Claim 10

The process of claim 6 wherein said polymerizing is conducted in the presence of up to 10 percent by volume of hydrogen, based on the ethylene charged.

Claim 11

The process of claim 6 wherein said polymerizing is conducted in the presence of a saturated hydrocarbon solvent having five to nine carbon atoms.