Method to make single-layer pet bottles with high barrier and improved clarity

• US 7,943,216 B2
• Filed: 04/27/2010
• Issued: 05/17/2011
• Est. Priority Date: 08/26/2003
• Status: Expired due to Fees

• Current Assignee: Trevira Holdings GmbH (Indorama Group)
• Original Assignee: Invista North America Sarl (Invista)
• Inventors: Huang, Xiaoyan, Mehta, Sanja, Schiraldi, David A, Liu, Zhenguo
• Primary Examiner(s): WOODWARD, ANA LUCRECIA
• Application Number:
  US12/768,541
• Publication Number:
  US 20100209641A1
• Time in Patent Office: 385 Days
• Field of Search: 525/425, 524/413, 524/435, 524/538, 428/34.1, 428/35.7, 428/36.9
• US Class Current: 428/34.1
• CPC Class Codes: B29C 2049/7879 Stretching, e.g. stretch rod
• CPC Class Codes: B29C 2949/0715 the preform having one end closed
• CPC Class Codes: B29C 2949/22 at neck portion
• CPC Class Codes: B29C 2949/24 at flange portion
• CPC Class Codes: B29C 2949/26 at body portion
• CPC Class Codes: B29C 2949/28 at bottom portion
• CPC Class Codes: B29C 2949/3024 characterised by the number of components or by the manufacturing technique
• CPC Class Codes: B29C 2949/3032 having components being injected
• CPC Class Codes: B29C 2949/3041 having components being extruded
• CPC Class Codes: B29C 49/0005 characterised by the material
• CPC Class Codes: B29C 49/06 Injection blow-moulding
• CPC Class Codes: B29C 49/087 Means for providing controlled or limited stretch ratio
• CPC Class Codes: B29K 2067/00 Use of polyesters or derivatives thereof, as moulding material
• CPC Class Codes: B65D 1/0207 characterised by material, e.g. composition, physical features
• CPC Class Codes: C08G 63/6886 Dicarboxylic acids and dihydroxy compounds
• CPC Class Codes: C08K 3/24 Acids; Salts thereof C08K3/16 takes precedence
• CPC Class Codes: C08K 5/098 Metal salts of carboxylic acids
• CPC Class Codes: C08K 5/42 Sulfonic acids; Derivatives thereof
• CPC Class Codes: C08L 2666/20 Macromolecular compounds having nitrogen in the main chain according to C08L75/00 - C08L79/00; Derivatives thereof
• CPC Class Codes: C08L 67/02 Polyesters derived from dicarboxylic acids and dihydroxy compounds C08L67/06 takes precedence
• CPC Class Codes: C08L 77/06 : Polyamides derived from polyamines and polycarboxylic acids C08L77/10 takes precedence
• CPC Class Codes: Y10T 428/13 : Hollow or container type article [e.g., tube, vase, etc.]
• CPC Class Codes: Y10T 428/1352 : Polymer or resin containing [i.e., natural or synthetic]
• CPC Class Codes: Y10T 428/139 : Open-ended, self-supporting conduit, cylinder, or tube-type article
• CPC Class Codes: Y10T 428/1397 : Single layer [continuous layer]

Abstract

The present invention comprises a blend of polyester and a partially aromatic polyamide with an ionic compatibilizer and a cobalt salt. This blend can be processed into a container that has both active and passive oxygen barrier and carbon dioxide barrier properties at an improved color and clarity than containers known in the art. The partially aromatic polyamide is preferably meta-xylylene adipamide. The ionic compatibilizer is preferably 5-sodiumsulfoisophthalic acid or 5-zincsulfoisophthalic acid, or their dialkyl esters such as the dimethyl ester (SIM) and glycol ester (SIPEG). The cobalt salt is selected form the class of cobalt acetate, cobalt carbonate, cobalt chloride, cobalt hydroxide, cobalt naphthenate, cobalt oleate, cobalt linoleate, cobalt octoate, cobalt stearate, cobalt nitrate, cobalt phosphate, cobalt sulfate, cobalt (ethylene glycolate), or mixtures of two or more of these. The partially aromatic polyamide is present in a range from about 1 to about 10 wt. % of said composition. The ionic compatibilizer is present in a range from about 0.1 to about 2.0 mol-% of said composition. The cobalt salt is present in a range from about 20 to about 500 ppm of said composition.

Claims

1. A composition for containers comprising:

a copolyester comprising a metal sulfonate salt;

a partially aromatic polyamide;

and a cobalt salt.

2. The composition of claim 1, wherein said partially aromatic polyamide is present in a range from about 1 to about 10 wt. % of said composition.

3. The composition of claim 2, wherein said metal sulfonate salt is present in a range from about 0.1 to about 2.0 mole % of said composition.

4. The composition of claim 1, wherein said cobalt salt is present in a range from about 20 to about 500 ppm of said composition.

5. The composition of claim 1, wherein said partially aromatic polyamide is meta-xylylene adipamide.

6. The composition of claim 1, wherein said partially aromatic polyamide is selected from the group consisting of poly(hexamethylene isophthalamide), poly(hexamethylene adipamide-co-isophthalamide), poly(hexamethylene adipamide-co-terephthalamide), poly(hexamethylene isophthalamide-co-terephthalamide), and mixtures of two or more of these.

7. The composition of claim 1, wherein said cobalt salt is selected from the group consisting of cobalt acetate, cobalt carbonate, cobalt chloride, cobalt hydroxide, cobalt naphthenate, cobalt oleate, cobalt linoleate, cobalt octoate, cobalt stearate, cobalt nitrate, cobalt phosphate, cobalt sulfate, cobalt (ethylene glycolate), and mixtures of two or more of these.

8. The composition of claim 1, wherein the metal ion of the metal sulfonate salt is selected from the group consisting of Na+, Li+, K+, Zn++, Mn++, and Ca++.

9. The composition of claim 8, wherein said metal sulfonate salt is attached to an aromatic acid nucleus selected from the group consisting of sulfophthalic acid, sulfoterephthalic acid, sulfoisophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, and esters of each.

10. The composition of claim 1, wherein said metal sulfonate salt is 5-sodiumsulfoisophthalic acid, 5-zincsulfoisophthalic acid, or dialkyl esters thereof.

11. The composition of claim 10, wherein the dialkyl ester is a dimethyl ester (SIM) or a glycol ester (SIPEG).

12. An article comprising the composition of any one of claims 1-11;

wherein said article is a preform or a container.

13. The article of claim 12, wherein the article is a container having an oxygen permeation rate of <

0.01 cc(STP)-cm/m²-atm-day after 100 hours in oxygen.

14. The container of claim 13, having a yellowness value (b*) of less than 2.5.

15. The article of claim 12, wherein the article is a container that has a carbon dioxide transmission rate of less than 7 cc/bottle/day, based on a 0.59 liter bottle.