Transparent poly(phenylene ether) compositions, their methods of manufacture, and food packaging films and containers derived therefrom

Patent metadata

Field	Value
Publication number	US-9845388-B2
Application number	US-201515532415-A
Country	US
Kind code	B2
Filing date	Sep 30, 2015
Priority date	Dec 5, 2014
Publication date	Dec 19, 2017
Grant date	Dec 19, 2017

Abstract

This invention generally relates to transparent compositions containing a blend of poly(phenylene ether) and styrenic polymer, methods for their manufacture, and food packaging films and containers derived therefrom.

First claim

The invention claimed is:

1. A microwavable food package or food wrapping film fabricated from a polymer composition which comprises a blend of 13 to 94 percent by weight of master batch and 87 to 6 percent by weight of styrenic polymer, wherein the master batch comprises:
(a) 40 to 75 percent by weight of a poly(phenylene ether);
(b) 25 to 60 percent by weight of a styrenic polymer;
(c) 0.01 to 2.5 percent by weight of an optical enhancing additive; wherein the optical enhancing additive is an alpha-hydroxyketone selected from the group consisting of hydroxyacetone (1-hydroxy-2-propanone); acetoin (3-hydroxy-2-butanone); 2-hydroxyacetophenone; benzoin (2-hydroxy-2-phenylacetophenone); and 2-hydroxy-1-phenyl-2-p-tolyl-ethanone;
(d) 0.003 to 0.012 percent by weight of a colorant;
(e) 0.01 to 2 percent by weight of a di- or trifunctional carboxylic acid selected from the group consisting of citric acid, fumaric acid, itaconic acid, and malic acid, and mixtures thereof; and wherein:
the master batch is characterized by:
(i) a heat deflection temperature that is 92° C. to 146° C. as measured according to ASTM D648 on 6.4 mm thick bars at 1.82 MPa;
(ii) a Haze value of less than 5; and

and the blend is characterized by:
(i) a heat deflection temperature that is 92° C. to 146° C. as measured according to ASTM D648 on 6.4 mm thick bars at 1.82 MPa; and
(ii) a Haze value of less than 3 as measured according to; and
(iii) a Yellowness index for films that are 200 micrometers thick of between −5 and 2.5; and provided:
when di- or trifunctional carboxylic acid is present, the microwavable food package or wrapping film contains 1250 or less specks that are 200 μm in size or larger in 1 m 2 as measured according to film surface analyzer; and further provided:
when there is 0.009 to 0.012 percent by weight of colorant present in the composition, the amount of di- or trifunctional carboxylic acid is greater than 0 percent by weight.

2. The microwavable food package or food wrapping film of claim 1 , wherein a film that is fabricated from the composition contains 300 or less specks that are 200 μm in size or larger in 1 m 2 of the film.

3. The microwavable food package or food wrapping film of claim 1 , wherein the poly(phenylene ether) is poly(2,6-dimethyl-1,4-phenylene ether) having an intrinsic viscosity of approximately 0.29-0.49 dL/g as measured in chloroform at 25° C.

4. The microwavable food package or food wrapping film of claim 1 , wherein the styrenic polymer is a general purpose polystyrene.

5. The microwavable food package or food wrapping film of claim 1 , wherein the optical enhancing additive is benzoin.

6. The microwavable food package or food wrapping film of claim 1 , wherein 0.008 to 0.012 percent by weight of colorant is present in the master batch.

7. The microwavable food package or food wrapping film of claim 1 , wherein the di- or trifunctional carboxylic acid is fumaric acid, citric acid, or a mixture thereof.

8. The microwavable food package or food wrapping film of claim 1 , wherein the master batch comprises:
(a) 40 to 60 percent by weight of a poly(phenylene ether);
(b) 40 to 60 percent by weight of a styrenic polymer;
(c) 0.25 to 2.40 percent by weight of benzoin;
(d) 0.004 to 0.012 percent by weight of a colorant;
(e) 0.01 to 2 percent by weight of a carboxylic acid which is fumaric acid, citric acid, or a mixture thereof
wherein the master batch is characterized by:
(i) a heat deflection temperature that is 105° C. to 140° C. as measured according to ASTM D648 on 6.4 mm thick bars at 1.82 MPa;
(ii) a Notched Izod Impact of 1.5 to 3.5 kg cm/cm as measured according to ASTM D256;
(iii) a Haze value of less than 3;
(iv) a melt flow rate of 10 to 100 g/10 min at 300° C., 5 kg loading as measured according to ASTM D1238;

and the blend comprises 16 to 94 percent by weight of master batch and 6 to 84 percent by weight of styrenic polymer, wherein the blend is characterized by:
(i) a heat deflection temperature that is 105° C. to 138° C. as measured according to ASTM D648 on 6.4 mm thick bars at 1.82 MPa.

9. A process for preparing a polymer composition for microwavable food container and film fabrication, comprising:
compounding to form a master batch comprising:
(a) 40 to 75 percent by weight of a poly(phenylene ether);
(b) 25 to 60 percent by weight of a styrenic polymer;
(c) 0.01 to 2.5 percent by weight of an optical enhancing additive; wherein the optical enhancing additive is an alpha-hydroxyketone selected from the group consisting of hydroxyacetone (1-hydroxy-2-propanone); acetoin (3-hydroxy-2-butanone); 2-hydroxyacetophenone; benzoin (2-hydroxy-2-phenylacetophenone); and 2-hydroxy-1-phenyl-2-p-tolyl-ethanone;
(d) 0.003 to 0.012 percent by weight of a colorant;
(e) 0.01 to 2 percent by weight of a di- or trifunctional carboxylic acid selected from the group consisting of citric acid, fumaric acid, itaconic acid, and malic acid, and mixtures thereof; and wherein:
the master batch is characterized by:
(i) a heat deflection temperature that is 92° C. to 146° C. as measured according to ASTM D648 on 6.4 mm thick bars at 1.82 MPa;
(ii) a Haze value of less than 5; and

blending the master batch with additional styrenic polymer to form a blend comprising 13 to 94 percent by weight of master batch and 87 to 6 percent by weight of styrenic polymer, wherein the blend is characterized by:
(i) a heat deflection temperature that is 92° C. to 146° C. as measured according to ASTM D648 on 6.4 mm thick bars at 1.82 MPa; and
(ii) a Haze value of less than 3 as measured according to; and
(iii) a Yellowness index for films that are 200 micrometer in thick of between −5 and 2.5; and provided:
when di- or trifunctional carboxylic acid is present, the microwavable food package or wrapping film contains 1250 or less specks that are 200 μm in size or larger in 1 m 2 as measured according to film surface analyzer; and further provided:
when there is 0.009 to 0.012 percent by weight of colorant present in the composition, the amount of di- or trifunctional carboxylic acid is greater than 0 percent by weight.

10. The process of claim 9 , wherein the master batch is compounded in an extruder at high temperature and the master batch is blended with the styrenic polymer in an extruder.

Assignees

• Sabic Global Technologies Bv

Inventors

• Takamura Norihiro

Classifications

• C08J2371/12

  Polyphenylene oxides · CPC title

• B29C47/0021

  Operations & Transport · mapped topic

• B65D81/3461

  Flexible containers, e.g. bags, pouches, envelopes · CPC title

• C08J2325/06

  Polystyrene · CPC title

• B65D65/02

  Wrappers or flexible covers · CPC title