POLYMER COMPOSITION WITH ENHANCED GAS BARRIER, ARTICLES AND METHODS
The present invention relates to a thermoplastic polymer composition with enhanced gas barrier properties comprising a thermoplastic polymer, an antiplasticizer and a chain extender. Suitable antiplasticizers and suitable chain extenders are disclosed herein. Other embodiments of the present invention include a method to produce such a thermoplastic composition, an article comprising such a thermoplastic composition, and a method for making such an article.
1 . A thermoplastic composition comprising: a thermoplastic polymer, an antiplasticizer, and a chain extender.
2 . The composition of claim 1 wherein said thermoplastic polymer is a polyester or copolyester.
3 . The composition of claim 2 wherein said thermoplastic polymer is selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate, polyethylene isophthalate, copolymers of polyethylene terephthalate, copolymers of polyethylene naphthalate, and copolymers of polyethylene isophthalate.
4 . The composition of claim 3 wherein said thermoplastic polymer is a copolymer of polyethylene terephthalate.
5 . The composition of claim 1 wherein said antiplasticizer is selected from the group consisting of:
R 1 O—Ar—OR 2 , R 1 OOC—Ar—COOR 2
HO—Ar—COOR, HO—Ar—COOR 1 COO—Ar—OH, HO—Ar—CONHR,
HO—Ar—CO—NHR 3 —COO—Ar—OH, and HO—Ar—CONHR 2 NHCO—AR—OH;
wherein Ar is selected from the group consisting of substituted phenylene, unsubstituted phenylene, substituted naphthalene, and unsubstituted naphthalene; R 1 , R 2 , and R 3 are selected from the group consisting of hydrogen, C 1 to C 6 alkyl groups, a phenyl group, and a naphthyl group.
6 . The composition of claim 5 wherein said antiplasticizer is dimethyl naphthalate.
7 . The composition of claim 1 wherein said chain extender is selected from the group consisting of bisanhydrides, bisoxazolines, bisepoxides and carbonyl bis caprolactams.
8 . The composition of claim 7 wherein said chain extender is carbonyl bis caprolactam.
9 . A composition comprising a polyester or copolyester, dimethyl naphthalate and carbonyl his caprolactam.
10 . The composition of claim 1 wherein said antiplasticizer is present in an amount of about 1 to about 10 weight % of the total composition.
11 . The composition of claim 1 wherein the chain extender is present in an amount of about 0.02 to about 2 weight % of the total composition
12 . A method of reducing gas permeability of shaped thermoplastic polymer articles wherein said thermoplastic polymer is the composition of claim 1 comprising:
a) incorporating into said thermoplastic polymer said antiplasticizer and said chain extender,
b) heating the mixture to melt the said thermoplastic polymer, and
c) forming the shaped thermoplastic polymer article.
13 . A shaped thermoplastic polymer article comprising the composition of claim 1 .
14 . A method of making a shaped thermoplastic polymer container comprising the thermoplastic composition of claim 1 comprising:
a) blending said thermoplastic polymer, said antiplasticizer and said chain extender to form a resin;
b) extruding said resin to form a perform; and
c) stretch blow molding said preform into the shaped thermoplastic polymer container.
15 . A method of making a thermoplastic polymer article comprising the thermoplastic composition of claim 1 comprising:
a) blending said thermoplastic polymer, said antiplasticizer and said chain extender to form a resin; and
b) extruding said resin to form the thermoplastic polymer article.