Oligomers and homopolymers of meta- or para-isopropenyl-α,α-dimethylbenzylisocyanate

Claim 3

A method according to claim 1 wherein said solvent is methylene chloride.

Claim 4

A method according to claim 1 of forming oligomers wherein said polymerization catalyst is anhydrous p-toluenesulfonic acid, said temperature in step (a) is from about -25° C. to about 0° C. and said temperature in step (b) is from about -25° C. to about 5° C.

Claim 5

A method according to claim 3 wherein said catalyst is neutralized by contacting polymerization solution from step (a) with neutral alumina.

Claim 6

A method according to claim 4 wherein said contacting is conducted by flowing said polymerization solution through a column of neutral alumina.

Claim 7

A method according to claim 1 wherein said catalyst is neutralized by addition of a neutralizingly effective amount of pyridine to the polymerization solution from step (a).

Claim 8

A method according to claim 1 wherein: (i) said polymerization catalyst is stannic chloride; (ii) said temperature in step (a) is from about -80° C. to about -20° C.; (iii) said temperature in step (b) is from about -80° C. to -20° C.; (iv) said polymerization catalyst is neutralized by addition of a neutralizingly effective amount of pyridine to the polymerization solution from step (a); and (v) polymerization in step (a) is conducted for a reaction time of from about 3 to about 30 minutes.

Claim 9

A method according to claim 7 of forming homopolymers of peak molecular weight in the range of from about 2,000 to about 12,000, wherein polymerization in step (a) is conducted in the presence of a chain transferringly effective amount of a tertiary benzylic chloride compound.

Claim 10

A method according to claim 8 wherein said polymerization in step (a) is conducted for a reaction time of from about 3 to about 15 minutes.

Claim 11

A method according to claim 8 wherein said tertiary benzylic chloride compound is α-chlorocumene.

Claim 12

A method according to claim 8 wherein said tertiary benzylic chloride compound is tetramethylxylylenedichloride.

Claim 13

A process for forming homopolymers of meta- or para-isopropenyl-α,α-dimethylbenzylisocyanate, comprising: (a) passing a first stream comprising a methylene chloride solution of meta- or para-isopropenyl-α,α-dimethylbenzylisocyanateinto a first reaction zone; (b) concurrently with step (a), passing a second stream comprising a methylene chloride solution of a catalytically effective amount of stannic chloride into said first reaction zone to form therein with said first stream a reaction volume; (c) maintaining said reaction volume under mixing conditions in said first reaction zone at a temperature from about -80° C. to about -25° C. for a time sufficient to polymerize said meta- or para-isopropenyl-α,α-dimethylbenzylisocyanate therein to a predetermined extent; (d) passing a stream of the polymerized reaction volume from said first reaction zone to a second reaction zone; (e) concurrently with step (d) passing to said second reaction zone a third stream comprising a methylene chloride solution containing pyridine in sufficient concentration and at sufficient flow rate of said third stream to neutralize said stannic chloride by complexing of pyridine therewith; (f) discharging neutralized homopolymer-containing solution from said second reaction zone; and (g) recovering said homopolymer from said discharged homopolymer-containing solution.

Claim 14

A process for forming homopolymers of meta- or para-isopropenyl-α,α-dimethylbenzylisocyanate, comprising: (a) passing a first stream comprising a methylene chloride solution of meta- or para-isopropenyl-α,α-dimethylbenzylisocyanateinto a first reaction zone; (b) concurrently with step (a), passing a second stream comprising a methylene chloride solution of a catalytically effective amount of stannic chloride into said first reaction zone to form therein with said first stream a reaction volume; (c) maintaining said reaction volume under mixing conditions in said first reaction zone at a temperature from about -80° C. to about -25° C. for a time sufficient to polymerize said meta- or para-isopropenyl-α,α-dimethylbenzylisocyanate therein to a predetermined extent; (d) passing a stream of the polymerized reaction volume from said first reaction zone to a second reaction zone; (e) concurrently with step (d) passing to said second reaction zone a third stream comprising a methylene chloride solution containing pyridine in sufficient concentration and at sufficient flow rate of said third stream to neutralize said stannic chloride by complexing of pyridine therewith; (f) discharging neutralized homopolymer-containing solution from said second reaction zone; and (g) recovering said homopolymer from said discharged homopolymer-containing solution.

Claim 15

A process according to claim 12 wherein said recovering step (g) comprises: (i) heating said discharged homopolymer-containing solution to a temperature of from about 80° C. to about 120° C. (ii) filtering said heated solution from step (i); and (iii) recovering said homopolymer from the filtered homopolymer solution.

Claim 16

A process according to claim 13 wherein said recovering step (iii) comprises evaporating said filtered homopolymer solution to recover said homopolymer as a residual solid.

Claim 17

A process according to claim 12 wherein said methylene chloride solution of meta- or para-isopropenyl-α,α-dimethylbenzylisocyanate contains a chain transferringly effective amount of α-chlorocumene.