Synthesis of polyol bis(allyl carbonate) utilizing reagent recovery and recycle

Claim 2

In a method of forming bis(allyl carbonate) monomer represented by the formula: ##STR5## where R 1 and R 3 are allyl groups represented by the formula: ##STR6## where R' is chosen from the group consisting of H, a halogen, and a 1 to 4 carbon alkyl group, and R 2 is chosen from the group consisting of alkylene groups, alkylene ether groups, and alkylene polyether groups, comprising: (a) forming a first reaction solution of bis(chloroformate) and allyl alcohol; (b) adding aqueous alkali metal hydroxide to the reaction solution whereby to form bis(allyl carbonate); and (c) recovering (1) an organic phase containing bis(allyl carbonate) monomer, and (2) an aqueous phase containing water soluble organics and unreacted allyl alcohol reagent: the improvement comprising: (a) distilling said aqueous phase into a high-boiling residue and a low-boiling distillate, wherein said distillate contains a water-allyl alcohol azeotrope; and (b) feeding said distillate to a second reaction solution containing bis(chloroformate).

Claim 3

The method of claim 1 comprising first separating said aqueous phase into an organic portion and an aqueous portion, and thereafter distilling said aqueous portion into the high-boiling residue and the low-boiling distillate.

Claim 4

The method of claim 1 wherein the bis(allyl carbonate) is diethylene glycol bis(allyl carbonate).

Claim 5

The method of claim 1 wherein the alkali metal hydroxide is chosen from the group consisting of sodium hydroxide and potassium hydroxide.

Claim 6

The method of claim 1 further comprising adding the aqueous alkali metal hydroxide to the second reaction mixture subsequent to adding the water-allyl alcohol azeotrope thereto.

Claim 7

The method of claim 1 further comprising adding excess alkali metal hydroxide to the second reaction mixture.

Claim 8

The method of claim 1 comprising: (a) washing said organic phase with clean water, and recovering return wash water and cleaned organic phase; (b) contacting the product of said first reaction solution with said return wash water from (a) whereby to wash said product; (c) thereafter separating the said product of the first reaction solution into the said organic phase and the said aqueous phase, said aqueous phase further containing the wash water; (d) distilling said aqueous phase into an aqueous portion and an organic portion; and (e) feeding said organic portion to said second reaction solution.

Claim 9

In a method of forming bis(allyl carbonate) monomer represented by the formula: ##STR7## where R 1 and R 3 are allyl groups represented by the formula: ##STR8## where R' is chosen from the group consisting of H, a halogen, and a 1 to 4 carbon alkyl group, and R 2 is chosen from the group consisting of alkylene groups, and alkylene polyether groups, comprising: I. (a) forming a first reaction solution of bis(chloroformate) and allyl alcohol; (b) adding aqueous alkali metal hydroxide to the reaction solution whereby to form bis(allyl carbonate); and (c) recovering (1) an organic phase containing bis(allyl carbonate); and (2) an aqueous phase containing water soluble organics and unreacted allyl alcohol; the improvement comprising: II. (a) washing the organic phase from step I.-(c)-(1) with clean water, and recovering cleaned organic phase and recycle wash water; (b) contacting the reaction product of a first subsequent reaction solution with said recycle wash water recovered from II.-(a); (c) separating the reaction product of the first reaction solution, washed in step II.-(a), into the organic phase and the aqueous phase; (d) distilling the aqueous phase into an organic portion and an aqueous portion; and (e) feeding the organic portion to a subsequent reaction solution comprising allyl alcohol and chloroformate.

Claim 10

In a method of forming bis(allyl carbonate) monomer represented by the formula: ##STR7## where R 1 and R 3 are allyl groups represented by the formula: ##STR8## where R' is chosen from the group consisting of H, a halogen, and a 1 to 4 carbon alkyl group, and R 2 is chosen from the group consisting of alkylene groups, and alkylene polyether groups, comprising: I. (a) forming a first reaction solution of bis(chloroformate) and allyl alcohol; (b) adding aqueous alkali metal hydroxide to the reaction solution whereby to form bis(allyl carbonate); and (c) recovering (1) an organic phase containing bis(allyl carbonate); and (2) an aqueous phase containing water soluble organics and unreacted allyl alcohol; the improvement comprising: II. (a) washing the organic phase from step I.-(c)-(1) with clean water, and recovering cleaned organic phase and recycle wash water; (b) contacting the reaction product of a first subsequent reaction solution with said recycle wash water recovered from II.-(a); (c) separating the reaction product of the first reaction solution, washed in step II.-(a), into the organic phase and the aqueous phase; (d) distilling the aqueous phase into an organic portion and an aqueous portion; and (e) feeding the organic portion to a subsequent reaction solution comprising allyl alcohol and chloroformate.

Claim 11

The method of claim 8 comprising distilling the aqueous portion of said aqueous phase into a high-boiling residue and a low-boiling distillate, said low-boiling distillate comprising a water-allyl alcohol azeotrope, and feeding said water-allyl alcohol azeotrope distillate to a subsequent reaction solution.

Claim 12

The method of claim 9 comprising adding the aqueous alkali metal hydroxide to the subsequent reaction mixture prior to adding the water-allyl alcohol azeotrope thereto.

Claim 13

The method of claim 8 comprising adding excess alkali metal hydroxide to the second reaction mixture.

Claim 14

The method of claim 8 wherein the bis(allyl carbonate) is diethylene glycol bis(allyl carbonate).

Claim 15

The method of claim 8 wherein the alkali metal hydroxide is chosen from the group consisting of sodium hydroxide and potassium hydroxide.