Articles Having Improved Gas Barrier Properties

The method of manufacturing sulfo-modified copolyester, comprising the steps of:

• a) reacting terephthalic acid (TA) or C1-C4-dialkyl terephthalate;
• and ethylene glycol (EG);
• and at least 2.0 but not more than 15 mole % isophthalic acid (IPA) or C1-C4-dialkyl isophthalate;
• and at least 0.5, but not more than 5.0 mol % of a compound according to formula (II):
• wherein R is hydrogen, a C1-C4-alkyl or a C1-C4-hydroxyalkyl and M is an alkali metal ion, earth alkali metal ion, phosphonium ion or ammonium ion;
• and
• wherein
• wherein n is an integer from 3 to 10.

The method of manufacturing a blend of sulfo-modified copolyester and polyglycolic acid, comprising the steps of

• a) preparing a master batch of sulfo-modified copolyester by reacting isophthalic acid or C1-C4-dialkyl isophthalate or 1,4-cyclohexanedimethanol, and a compound according to formula (II):
• wherein R is hydrogen, a C1-C4-alkyl or a C1-C4-hydroxyalkyl, and wherein
• wherein n is an integer from 3 to 10 and
• wherein M is an alkali metal ion, earth alkali metal ion, phosphonium ion or ammonium ion;
• and
• b) melt blending to the master batch of step a) polyglycolic acid and a polyester resin, thereby forming said blend of sulfo-modified copolyester and polyglycolic acid having at least 2.0 but not more than 15 mole % isophthalic acid (IPA) or C1-C4-dialkyl isophthalate or 1,4 cyclohexanedimethanol;
• and at least 0.5, but not more than 5.0 mol % of the compound of formula (II);
• and about 1 to about 10 wt. % of polyglycolic acid, based on the weight of the blend of sulfo-modified copolyester and polyglycolic acid.

The method of manufacturing a blend of sulfo-modified copolyester and polyglycolic acid, comprising the steps of

• a) preparing a master batch of sulfo-modified copolyester by reacting isophthalic acid or C1-C4-dialkyl isophthalate or 1,4 cyclohexanedimethanol, and a compound according to formula (II):
• wherein R is hydrogen, a C1-C4-alkyl or a C1-C4-hydroxyalkyl, and wherein
• wherein n is an integer from 3 to 10 and
• wherein M is an alkali metal ion, earth alkali metal ion, phosphonium ion or ammonium ion;
• and
• b) melt blending to the master batch of step a) polyglycolic acid to form a master batch resin, and
• c) melt blending to the master batch resin of step b) polyester resin, thereby forming a blend of sulfo-modified copolyester and polyglycolic acid having at least 2.0 but not more than 15 mole % isophthalic acid or 1,4 cyclohexanedimethanol, or C1-C4-dialkyl isophthalate;
• and at least 0.5, but not more than 5.0 mol % of the compound of formula (II);
• and about 1 to about 10 wt. % of polyglycolic acid, based on the weight of the sulfo-modified copolyester and polyglycolic acid.

A master batch resin comprising:

• the reaction product of isophthalic acid or C1-C4-dialkyl isophthalate or 1,4-cyclohexanedimethanol, and a compound according to formula (II):
• wherein R is hydrogen, a C1-C4-alkyl or a C1-C4-hydroxyalkyl, and wherein
• wherein n is an integer from 3 to 10 and
• wherein M is an alkali metal ion, earth alkali metal ion, phosphonium ion or ammonium ion.

A master batch resin comprising:

• the reacted product of isophthalic acid or C1-C4-dialkyl isophthalate or 1,4 cyclohexanedimethanol, and a compound according to formula (II):
• wherein R is hydrogen, a C1-C4-alkyl or a C1-C4-hydroxyalkyl, and wherein
• wherein n is an integer from 3 to 10 and
• wherein M is an alkali metal ion, earth alkali metal ion, phosphonium ion or ammonium ion;
• and polyglycolic acid to form said master batch resin.