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US4966949A
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Process for increasing the molecular weight of a polyamide with p containing catalyst
Assignee: Invista North America LLC
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Filing: 1988-10-20
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Granted: 1990-10-30
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Expires: 2008-10-20
Abstract
Abstract This invention relates to an improved process for increasing the molecular weight of a polyamide.
Inventors
- 👤 Robert C. Wheland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:22
CPC Classifications
C; C08; C08G; C08G69/00; C08G69/02; C08G69/04; C08G69/08; C08G69/14; C08G69/16; C08G69/18; C08G69/20; C08G69/26; C08G69/28
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
218 words
In a process for increasing the molecular weight of a polyamide, consisting essentially of heating the polyamide in the presence of a catalyst, for a sufficient reaction time, to effect a desired increase in molecular weight, wherein the improvement consists essentially of employing, as the catalyst, at least one compound of the formulae selected from A or B: ##STR3## wherein R 2 , R 4 , and R 6 are independently selected from the group H, R 2 N--, RO--, RS--, or R--, wherein R is C x H 2x1 with x=1 to 10, C 6 H5 or C 6 H5CH 2 -- with the proviso that R 2 , R 4 or R 6 be other than hydrogen when any two of R 2 , R 4 and R 6 are H simultaneously and R 3 and R 5 are independently selected from the group H, R 2 N--, RO--, RS--, or R, wherein R is C x H 2x+1 with x=1 to 10, C 6 H 5 -- or C 6 H 5 CH 2 -- with the further proviso that when R 2 , R 3 , R 4 , R 5 , and R 6 are H or R, then at least one of R 2 or R 6 must be an R group.
Claim 2
Dependent Claim
218 words
In a process for increasing the molecular weight of a polyamide, consisting essentially of heating the polyamide in the presence of a catalyst, for a sufficient reaction time, to effect a desired increase in molecular weight, wherein the improvement consists essentially of employing, as the catalyst, at least one compound of the formulae selected from A or B: ##STR3## wherein R 2 , R 4 , and R 6 are independently selected from the group H, R 2 N--, RO--, RS--, or R--, wherein R is C x H 2x1 with x=1 to 10, C 6 H5 or C 6 H5CH 2 -- with the proviso that R 2 , R 4 or R 6 be other than hydrogen when any two of R 2 , R 4 and R 6 are H simultaneously and R 3 and R 5 are independently selected from the group H, R 2 N--, RO--, RS--, or R, wherein R is C x H 2x+1 with x=1 to 10, C 6 H 5 -- or C 6 H 5 CH 2 -- with the further proviso that when R 2 , R 3 , R 4 , R 5 , and R 6 are H or R, then at least one of R 2 or R 6 must be an R group.
Claim 3
Dependent Claim
91 words
The process of claim 1 wherein R 2 and R 4 are CH 3 O-- and R 3 , R 5 , and R 6 are H; R 2 is CH 3 O-- and R 3 , R 4 , R 5 , and R 6 are H; R 4 is CH 3 O-- and R 2 , R 3 , R 5 , and R 6 are H; R 2 and R 5 are CH 3 --, and R 3 , R 4 , and R 6 , are H.
Claim 4
Dependent Claim
28 words
The process of claim 1 wherein the catalysts are selected from 2-methoxyphenylphosphonic acid, 2,4-dimethoxyphenylphosphinic acid, 4-methoxyphenylphosphinic acid, 2,4-dimethoxyphenylphosphonic acid, 2,6-dimethylphenylphosphonic acid, 2-benzyloxyphenylphosphonic acid, 2-methylphenylphosphonic acid, or 4-methoxyphenylphosphonic acid.
Claim 5
Dependent Claim
77 words
The process of claim 1 wherein the polyamide is selected from H.sub.2 N--R'--NH--[C(═O)--R"--C(═O)--NH--R'--NH].sub.n --C(═O)--R"--COOH or H.sub.2 N--R'--C(═O)--[NH--R'--C(═O)].sub.n --NH--R'--COOH where R' is from the group consisting of linear or branched alkylene groups containing from 2 to 12 carbon atoms and aromatic groups and R" is from the group consisting of linear and branched alkylene groups containing from 2 to 12 carbons and n represents the degree of polymerization or the number of recurring groups in the polymer chain.
Claim 6
Dependent Claim
10 words
The process of claim 4 wherein the polyamide is nylon-6,6.
Claim 7
Dependent Claim
53 words
The process of claim 5 wherein the value of n is such that the molecular weight as measured by the change in relative viscosity is about 15,000 and the relative viscosity as measured in an 8.5% by weight solution of 6,6-nylon in 90% formic acid in water at 25 C. is about 40.
Claim 8
Dependent Claim
28 words
The process of claim 4 consisting of reacting the catalyst and the polyamide in a liquid phase reaction for a reaction time of about 1 to 60 minutes.
Claim 9
Dependent Claim
25 words
The process of claim 4 consisting of reacting the catalyst and the polyamide in a solid state reaction for a reaction time of >15 minutes.
References Cited (Backward Citations)
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