Thioethers having a high sulfur content and method therefor

Claim 1

A liquid polythioether containing no oxygen in the polymeric backbone which is non-crystallizing and water and fuel resistant having the following formula: ##STR20## wherein each of R 2 and R 3 is hydrogen or lower alkyl, each of R 1 and R 4 is lower alkyl, R is lower alkylene or lower alkyl thioether, p is 0 to 3, n is from about 8 to 200, r is 0 or 1, a is 0 or 1, m is 1, 3 or 4, the sum of a and r being 1, when m is 1, r is 1 and when m is 3 or 4, a is 1, R' is an organic divalent radical having no chemically reactive groups of an organic primary dimercaptan having the formula R'--(SH) 2 , each mercaptan group being primary and R" is a tri- or tetravalent organic fragment having no chemically reactive groups of the organic compound having the formula R"--(Z) q wherein Z is a secondary hydroxyl located beta to a sulfur atom or a primary mercaptan group and q is 3 or 4.

Claim 21

A method for producing a liquid polythioether which is non-crystallizing, is water and fuel resistant and has a molecular weight of between about 900 to about 25,000 which comprises forming a reaction admixture of (i) a di-secondary beta thioether diol reactant having the formula: ##STR23## wherein each of R 2 and R 3 is hydrogen or lower alkyl, each of R 1 and R 4 is lower alkyl, R is lower alkylene or lower alkyl thioether and p is 0 to 3, (ii) an organic primary dimercaptan reactant having the formula: R'--(SH).sub.2 wherein R' is a divalent organic radical and the mercaptan groups are primary, (iii) a catalytic effective amount of a non-oxidizing, strong acid dehydration catalyst in a sufficient amount of water to prevent said catalyst from oxidizing the reactants; and (iv) a branching agent reactant of the formula: R"--(Z).sub.q wherein q is 3 or 4 and R" is a tri- or tetravalent organic radical having no chemically reactive groups, Z is a secondary hydroxyl located beta to a sulfur atom or a primary mercaptan group; heating said reactants to a temperature of between about 90° C. and 140° C. to react substantially only the primary mercaptan group with the hydroxyl group and removing a sufficient amount of the water formed by the reaction to prevent the reaction from terminating until a liquid polythioether is formed having a molecular weight of between about 900 to about 25,000.

Claim 22

A method for producing a liquid polythioether which is non-crystallizing, is water and fuel resistant and has a molecular weight of between about 900 to about 25,000 which comprises forming a reaction admixture of (i) a di-secondary beta thioether diol reactant having the formula: ##STR23## wherein each of R 2 and R 3 is hydrogen or lower alkyl, each of R 1 and R 4 is lower alkyl, R is lower alkylene or lower alkyl thioether and p is 0 to 3, (ii) an organic primary dimercaptan reactant having the formula: R'--(SH).sub.2 wherein R' is a divalent organic radical and the mercaptan groups are primary, (iii) a catalytic effective amount of a non-oxidizing, strong acid dehydration catalyst in a sufficient amount of water to prevent said catalyst from oxidizing the reactants; and (iv) a branching agent reactant of the formula: R"--(Z).sub.q wherein q is 3 or 4 and R" is a tri- or tetravalent organic radical having no chemically reactive groups, Z is a secondary hydroxyl located beta to a sulfur atom or a primary mercaptan group; heating said reactants to a temperature of between about 90° C. and 140° C. to react substantially only the primary mercaptan group with the hydroxyl group and removing a sufficient amount of the water formed by the reaction to prevent the reaction from terminating until a liquid polythioether is formed having a molecular weight of between about 900 to about 25,000.

Claim 30

A method for producing a liquid polythioether which is non-crystallizing, is water and fuel resistant and has a molecular weight of between about 900 to about 25,000, which comprises forming a reaction admixture of (i) a secondary beta-hydroxy mercaptan reactant having the formula: ##STR24## wherein --SH is primary, R 5 is lower alkyl, R 6 is hydrogen or lower alkyl, t and u are each 0 or 1 the sum of u and t being 1, when t is 1, R 6 is hydrogen, and R'" is divalent organic radical; (ii) a catalytic effective amount of a non-oxidizing, strong acid dehydration catalyst in a sufficient amount of water to prevent said catalyst from oxidizing the reactants; and (iii) a polyhydroxy initiator reactant having the formula: R.sup.iv --(OH).sub.s wherein R iv is a di-, tri- or tetravalent organic compound having no chemically reactive groups, s is 2, 3 or 4 and each of the --OH groups are secondary and beta to a sulfur atom; or (iv) a polymercaptan initiator reactant having the formula: R.sup.v --(SH).sub.w wherein R v is an organic radical having no chemically reactive groups, the --(SH) groups are primary and w is 2, 3 or 4; heating said reactants to a temperature of between about 90° C. and 140° C. to react substantially only the primary mercaptan group with the hydroxyl group and removing a sufficient amount of the water formed by the reaction to prevent the reaction from terminating until a liquid polythioether is formed having a molecular weight of between about 900 to about 25,000.

Claim 31

A method for producing a liquid polythioether which is non-crystallizing, is water and fuel resistant and has a molecular weight of between about 900 to about 25,000, which comprises forming a reaction admixture of (i) a secondary beta-hydroxy mercaptan reactant having the formula: ##STR24## wherein --SH is primary, R 5 is lower alkyl, R 6 is hydrogen or lower alkyl, t and u are each 0 or 1 the sum of u and t being 1, when t is 1, R 6 is hydrogen, and R'" is divalent organic radical; (ii) a catalytic effective amount of a non-oxidizing, strong acid dehydration catalyst in a sufficient amount of water to prevent said catalyst from oxidizing the reactants; and (iii) a polyhydroxy initiator reactant having the formula: R.sup.iv --(OH).sub.s wherein R iv is a di-, tri- or tetravalent organic compound having no chemically reactive groups, s is 2, 3 or 4 and each of the --OH groups are secondary and beta to a sulfur atom; or (iv) a polymercaptan initiator reactant having the formula: R.sup.v --(SH).sub.w wherein R v is an organic radical having no chemically reactive groups, the --(SH) groups are primary and w is 2, 3 or 4; heating said reactants to a temperature of between about 90° C. and 140° C. to react substantially only the primary mercaptan group with the hydroxyl group and removing a sufficient amount of the water formed by the reaction to prevent the reaction from terminating until a liquid polythioether is formed having a molecular weight of between about 900 to about 25,000.