Production of polyisobutylene copolymers
AssigneeExxonMobil Chemical Patents Inc.
InventorsRobert N. Webb, Kenneth W. Powers, Michael F. McDonald, Ralph Howard Schatz
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Abstract
The invention relates to a new improved catalyst to produce random copolymers of one or more iso-olefin monomers and one or more para-alkylstyrene monomers. The invention also relates to an improved continuous slurry polymerization process to produce random copolymers using the improved catalyst system. The process is carried out in an anhydrous polymerization system containing a mixture of the monomers in a polar solvent along with a Lewis acid and a stabilizing initiator.
Claims51
A catalyst composition for polymerizing copolymers of isobutylene comprising:
- (a) a Lewis Acid based on a metal selected from boron, aluminum, gallium, indium, titanium, zirconium, tin, vanadium, arsenic, antimony, and bismuth;
- and
- (b) an initiator having the formula:
- 3
- wherein R1 is an alkyl, alkenyl, aryl, arylalkyl, or arylalkenyl group containing up to 30 carbon atoms but not less than 3 carbon atoms unless R1 contains at least one olefinic unsaturation;
- R2 and R3 are alkyl, aryl, or arylalkyl groups containing up to 30 carbon atoms and can be the same or different;
- X is a halogen or carboxy, hydroxyl, or alkoxyl group;
- and n is a positive whole number;
- wherein the catalyst efficiency based on Lewis Acid of the catalyst composition in a butyl type reactor in polymerizing copolymers of isobutylene is from 10,000 lb polymer/lb. catalyst to 300 lb. polymer/lb. catalyst.
A polymerization process for preparing isobutylene copolymers comprising combining monomers comprising isobutylene, at least one polar solvent, at least one Lewis Acid, and an initiator, the initiator having the formula:
- 4
- wherein R1 is an alkyl, alkenyl, aryl, arylalkyl, or arylalkenyl group containing up to 30 carbon atoms but not less than 3 carbon atoms unless R1 contains at least one olefinic unsaturation;
- R2 and R3 are alkyl, aryl, or arylalkyl groups containing up to 30 carbon atoms and can be the same or different;
- X is a halogen or a carboxy, hydroxyl, or alkoxyl group;
- and n is a positive whole number.
A polymerization process for preparing isobutylene copolymers in a reactor comprising:
- combining monomers comprising isobutylene;
- at least one polar solvent;
- and
- (a) at least one Lewis Acid selected from aluminum chloride, aluminum bromide, boron trifluoride, boron trichloride, ethyl aluminum dichloride (EtAlCl2 or EADC), diethyl aluminum chloride (Et2AlCl or DEAC), ethyl aluminum sesquichloride (Et1.5AlCl1.5 or EASC), trimethyl aluminum, and triethyl aluminum, or mixtures thereof;
- and
- (b) an initiator comprising 2-chloro-2-phenylpropane;
- 1,4-di(2-chloro-2-propyl)benzene;
- 1,3,5-tri(2-chloro-2-propyl)benzene;
- 3-tert-butyl-1,5-di(2-chloro-2-propyl)benzene;
- 2-chloro-2,4,4-trimethylpentane;
- or 2,6-dichloro-2,4,4,6-tetramethylheptane;
- wherein the mole ratio of Lewis Acid to initiator is from 1/1 to 20/1;
- and the mole ratio of Lewis Acid to monomer is from 1/60,000 to 1/50;
- and wherein the polymerization is performed at a temperature of between −10° C. and the freezing point of the polymerization system;
- and at a pressure of from 200 kPa to 1600 kPa in a butyl type reactor;
- and wherein the catalyst efficiency based on Lewis Acid of the catalyst composition in a butyl type reactor in polymerizing copolymers of isobutylene is from 10,000 lb polymer/lb. catalyst to 300 lb. polymer/lb. catalyst.
Dependencies are inferred from the claim text.