Organo-titanate catalysts for preparing pure macrocyclic oligoesters
AssigneeCyclics Corporation
InventorsPeter D. Phelps, Timothy A. Thompson, Yi-Feng Wang, Donald G. Le Grand
Life of this patent
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Abstract
Organo-titanate catalysts are prepared that are useful to catalyze depolymerization of a polyester to produce macrocyclic oligoesters substantially free from macrocyclic co-oligoesters.
Claims33
A mixture of reaction products of
- x(Ti—(OR1)4)+y(HO—R2—OH)+z((HO)—C(R3)(R4)—W—C(R5)(R6)—(OH)),
- the mixture being substantially free from di-functional diols other than HO—R2—OH,
- wherein
- each R1is independently a C1-C10 alkyl group;
- R2 is a C2-C6 alkylene group;
- each of R3, R4, R5, and R6 is independently a hydrogen atom or a C1-C4 alkyl group except that
- at least one of R3 and R4 is a C1-C4 alkyl group, and
- at least one of R5 and R6 is a C1-C4 alkyl group;
- W is an oxygen atom, a sulfur atom, a nitrogen-containing group, a phosphorus-containing group, or a C 1-C4 alkylene group;
- each of x and y is greater than 0;
- and
- y>z.
A mixture of reaction products of
- n(Ti—(OR1)4)+(2n−m)((HO—R2—OH)+m((HO) —C(R3)(R4)—W—C(R5)(R6)—(OH)),
- the mixture being substantially free from di-functional dials, wherein
- each R1 is independently a C1-C10 alkyl group;
- R2 is a C2-C6 alkylene group;
- each of R3, R4, R5, and R6 is independently a hydrogen atom or a C1-C4 alkyl group except that
- at least one of R3 and R4 is a C1-C4 alkyl group, and
- at least one of R5 and R6 is a C1-C4 alkyl group;
- W is an oxygen atom, a sulfur atom, a nitrogen-containing group, a phosphorus-containing group, or a C1-C4 alkylene group;
- and
- each of m and n is greater than 0.
A method for depolymerizing a polyester to produce macrocyclic oligoesters substantially free from macrocyclic co-oligoesters, the method comprising the step of contacting, in the presence of heat, a mixture comprising:
- a polyester, an organic solvent which is substantially free of oxygen and water, and a mixture of reaction products of:
- n(Ti—(OR1)4)+m(HO—R2—OH),
- wherein
- each R1 is independently a C1-C,10 alkyl group;
- R2 is an unbranched C2-C6 alkylene group;
- and
- each of m and n is greater than 0, and m/n>2.
A method for depolymerizing a polyester comprising the step of contacting, in the presence of heat, a polyester, an organic solvent, and a mixture of reaction products of
- x(Ti—(OR1)4)+y(HO—R2—OH)+z((HO)—C(R3)(R4)—W—C(R5)(R6)—(OH)),
- wherein
- each R1 is independently a C1-C10 alkyl group;
- R2 is a C2-C6 alkylene group;
- each of R3, R4, R5 and R6 is independently a hydrogen atom or a C1-C4 alkyl group;
- W is an oxygen atom, a sulfur atom, a nitrogen-containing group, a phosphorus-containing group, or a C1-C4 alkylene group;
- each of x and y is greater than 0;
- and
- y>z.
A method for depolymerizing a polyester comprising the step of contacting, in the presence of heat, a polyester, an organic solvent, and a mixture of reaction products of
- n(Ti—(OR1)4)+m(HO—R2—OH),
- wherein
- each R1 is independently a C1-C10 alkyl group;
- R2 is a C2-C6 alkylene group;
- and
- each of m and n is greater than 0, and m/n>2.
Dependencies are inferred from the claim text.