Copolymerizable phenolic antioxidant

Claim 2

An antioxidant having the structural formula: ##STR11## where R 1 is hydrogen or a lower alkyl radical; R 2 is a monovalent radical containing carbon, hydrogen, and oxygen, free of ethylenic or acetylenic unsaturation, and having a molecular weight between about 99-300 and, further, containing two carboxyl groups or their ester-forming equivalents; R 3 and R 4 are tertiary alkyl radicals each containing not more than 8 carbon atoms; and x is an integer of from 0-4.

Claim 3

An antioxidant of claim 1 wherein R 1 is hydrogen.

Claim 4

An antioxidant of claim 1 wherein R 2 contains two carboalkoxy groups.

Claim 5

An antioxidant of claim 1 wherein R 3 and R 4 are t-butyl.

Claim 6

An antioxidant of claim 1 wherein x equals 2.

Claim 7

An antioxidant of claim 1 wherein the carbon atom in R 2 which is linked to the amide nitrogen is saturated.

Claim 8

An antioxidant of claim 1 having the formula: ##STR12##

Claim 9

An antioxidant of claim 1 having the formula: ##STR13##

Claim 10

An antioxidant of claim 1 having the formula: ##STR14##

Claim 11

In a stabilized copolyetherester composition consisting essentially of a multiplicity of recurring long chain ester units and short chain ester units joined head-to-tail through ester linkages, said long chain ester units being represented by the formula ##STR15## and said short chain ester units being represented by the formula ##STR16## where G is a divalent radical remaining after the removal of terminal hydroxyl groups from a poly(alkylene oxide) glycol having a number average molecular weight of about 400-6000 and a carbon to oxygen atomic ratio of about 2.0-4.3; R is a divalent radical remaining after removal of carboxyl groups from a dicarboxylic acid having a molecular weight less than about 300, and D is a divalent radical remaining after removal of hydroxyl groups from a diol having a molecular weight less than about 250; provided said short chain ester units amount to about 15-95 percent by weight of said copolyetherester and characterized in that said copolyetherester is stabilized against oxidative degradation due to the presence in the backbone of the copolyetherester of an effective concentration of antioxidant units derived from: ##STR17## where R 1 is hydrogen or a lower alkyl radical; R 2 is a monovalent radical containing carbon, hydrogen, and oxygen, free of ethylenic or acetylenic unsaturation, and having a molecular weight between about 99-300 and, further, containing two carboxyl groups or their ester-forming equivalents; R 3 and R 4 are tertiary alkyl radicals each containing not more than 8 carbon atoms; and x is an integer of from 0-4, said antioxidant units being connected to ester units in the copolyetherester through ester linkages.

Claim 12

In a stabilized copolyetherester composition consisting essentially of a multiplicity of recurring long chain ester units and short chain ester units joined head-to-tail through ester linkages, said long chain ester units being represented by the formula ##STR15## and said short chain ester units being represented by the formula ##STR16## where G is a divalent radical remaining after the removal of terminal hydroxyl groups from a poly(alkylene oxide) glycol having a number average molecular weight of about 400-6000 and a carbon to oxygen atomic ratio of about 2.0-4.3; R is a divalent radical remaining after removal of carboxyl groups from a dicarboxylic acid having a molecular weight less than about 300, and D is a divalent radical remaining after removal of hydroxyl groups from a diol having a molecular weight less than about 250; provided said short chain ester units amount to about 15-95 percent by weight of said copolyetherester and characterized in that said copolyetherester is stabilized against oxidative degradation due to the presence in the backbone of the copolyetherester of an effective concentration of antioxidant units derived from: ##STR17## where R 1 is hydrogen or a lower alkyl radical; R 2 is a monovalent radical containing carbon, hydrogen, and oxygen, free of ethylenic or acetylenic unsaturation, and having a molecular weight between about 99-300 and, further, containing two carboxyl groups or their ester-forming equivalents; R 3 and R 4 are tertiary alkyl radicals each containing not more than 8 carbon atoms; and x is an integer of from 0-4, said antioxidant units being connected to ester units in the copolyetherester through ester linkages.

Claim 13

The composition of claim 10 wherein the concentration of said antioxidant units is about 0.2-10 percent by weight based on the weight of the copolyetherester.

Claim 14

The composition of claim 10 additionally containing an uncopolymerizable antioxidant.

Claim 15

The composition of claim 12 wherein said uncopolymerizable antioxidant is an arylamine or a hindered phenol.

Claim 16

The composition of claim 10 wherein R 1 is hydrogen.

Claim 17

The composition of claim 10 wherein R 2 contains two carboalkoxy groups.

Claim 18

The composition of claim 10 wherein R 3 and R 4 are t-butyl.

Claim 19

The composition of claim 10 wherein x equals 2.

Claim 20

The composition of claim 10 wherein the carbon atom in R 2 which is linked to the amide nitrogen is saturated.

Claim 21

The composition of claim 10 wherein said antioxidant has the formula: ##STR18##

Claim 22

The composition of claim 10 wherein said antioxidant has the formula: ##STR19##

Claim 23

The composition of claim 10 wherein said antioxidant has the formula: ##STR20##

Claim 24

The composition of claim 10 wherein said poly(alkylene oxide) glycol is poly(tetramethylene oxide) glycol having a number average molecular weight of 600-2000, the diol is 1,4-butanediol and the dicarboxylic acid is terephthalic acid containing up to 30 mole % isophthalic or phthalic acid.

Claim 25

A process for producing the composition of claim 10 which comprises reacting said poly(alkylene oxide) glycol, said dicarboxylic acid and said diol in the presence of a copolymerizable antioxidant having the formula: ##STR21## where R 1 is hydrogen or a lower alkyl radical; R 2 is a monovalent radical containing carbon, hydrogen, and oxygen, free of ethylenic or acetylenic unsaturation, and having a molecular weight between about 99-300 and, further, containing two carboxyl groups or their ester-forming equivalents; R 3 and R 4 are tertiary alkyl groups each containing not more than 8 carbon atoms; and x is an integer of from 0-4.

Claim 26

The process of claim 23 wherein said antioxidant is added in amounts of about 0.2-10 percent by weight based on the weight of the copolyetherester.

Claim 27

The process of claim 23 wherein R 1 is hydrogen.

Claim 28

The process of claim 23 wherein R 2 contains two carboalkoxy groups.

Claim 29

The process of claim 23 wherein R 3 and R 4 are t-butyl.

Claim 30

The process of claim 23 wherein x equals 2.

Claim 31

The process of claim 23 wherein the carbon atom in R 2 which is linked to the amide nitrogen is saturated.