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EP-4045320-B1 - ELASTOMER CONTAINING MULTILAYER FILM AND METHOD OF MANUFACTURE

EP4045320B1EP 4045320 B1EP4045320 B1EP 4045320B1EP-4045320-B1

Inventors

  • BERGEN SMITH, Angelica
  • SATTERWHITE, PAUL
  • MYERS, JOHN
  • GEER, Sarah Lynn

Dates

Publication Date
20260513
Application Date
20201015

Claims (15)

  1. A multilayer film comprising: at least one outer layer comprising at least 70% by weight of one or more of an ethylene/alpha-olefin copolymer; and at least one inner layer being an abuse layer comprising a blend of: at least 1% by weight of an anhydride grafted elastomer selected from the group consisting of ethylene propylene diene monomer, ethylene propylene copolymer, styrene-ethylene-butylene-styrene, ethylene/octene copolymer and blends thereof, the anhydride grafted elastomer having a grafting level between 0.1-3.0 wt%.; and at least 25% by weight one or more polyamides; wherein at least 5%, 10%, 20%, 30%, 40% or 50% by weight of the multilayer film being of one or more polyamides; the multilayer film having a haze measured according to ASTM D1003 not higher than 20%, and/or a gloss measured according to ASTM D 2457 of at least 90.
  2. The multilayer film according to claim 1 wherein the outer layer is a sealant layer comprising at least 50% by weight of a linear low density polyethylene.
  3. The multilayer film according to any one of the preceding claims, wherein the abuse layer comprises at least 3% or 5% of an anhydride grafted elastomer selected from the group consisting of ethylene propylene diene monomer, ethylene propylene copolymer, styrene-ethylene-butylene-styrene, ethylene/octene copolymer and blends thereof.
  4. The multilayer film according to any one of the preceding claims, wherein the anhydride grafted elastomer of the abuse layer is maleic anhydride grafted ethylene/octene copolymer.
  5. The multilayer film according to any one of the preceding claims, wherein the multilayer film further comprises and inner layer being a barrier layer disposed between the outer layer and the abuse layer, the multilayer film have an oxygen transmission rate of no more than 150 cubic centimeters (at standard temperature and pressure) per square meter per day per 1 atmosphere of oxygen pressure differential measured at 0% relative humidity and 23 □C as measured according to ASTM D-3985.
  6. The multilayer film according to any one of the preceding claims, wherein the one or more polyamides of the abuse layer comprises at least 50%, or at least 70% by weight of nylon-4; nylon-6; nylon-7; nylon-8; and blends thereof.
  7. The multilayer film according to any one of the preceding claims, wherein the multilayer film has a free shrink of less than 30% in any directions measured in accordance with ASTM D 2732.
  8. The multilayer film according to any one of the preceding claims further comprising a tie layer disposed between the outer layer and the abuse layer, the tie layer comprising at least 80% by weight of a maleic anhydride grafted linear low density polyethylene.
  9. The multilayer film according to any one of the preceding claims wherein the anhydride grafted elastomer is dispersed in the abuse layer as distinct spheroidal shaped particles having a mean domain size of less than 3.00 microns according to the formula: Domain size = 4 / π d mean diameter is measured by taking mean diameter (d mean ) of the domains across either the major or minor axis.
  10. The multilayer film according any one of the preceding claims wherein the multilayer film comprises: i. the at least one outer layer being a first outer layer comprising a blend of a linear low density polyethylene and a low density polyethylene; ii. a first tie layer directly adhered to the at least one outer layer on one side and the abuse layer on the other side, the first tie layer comprising a maleic anhydride modified linear low density polyethylene; iii. an inner layer directly adhered to the abuse layer on one side a second abuse layer on the other side; iv. the second abuse layer comprising a blend of: at least 1% by weight of a maleic anhydride grafted elastomer selected from the group consisting of ethylene propylene diene monomer, ethylene propylene copolymer, styrene-ethylene-butylene-styrene, ethylene/octene copolymer and blends thereof; and at least 25% by weight one or more polyamides; v. a second tie layer directly adhered to the second abuse layer on one side and a second outer layer on the other side, the second tie layer comprising a maleic anhydride modified linear low density polyethylene; and vi. the second outer layer comprising a blend of a linear low density polyethylene and a low density polyethylene.
  11. A food package comprising: a food product; a pouch containing the food product, the pouch being made from a multilayer film comprising: at least one outer layer comprising at least 70% by weight of one or more of an ethylene/alpha-olefin copolymer; and at least one inner layer being an abuse layer comprising a blend of: at least 1% by weight of an anhydride grafted elastomer selected from the group consisting of ethylene propylene diene monomer, ethylene propylene copolymer, styrene-ethylene-butylene-styrene, ethylene/octene copolymer and blends thereof, the anhydride grafted elastomer having a grafting level between 0.1-3.0 wt%.; and at least 25% by weight one or more polyamides; wherein at least 5%, 10%, 20%, 30%, 40% or 50% by weight of the multilayer film being of one or more polyamides; the multilayer film having a haze measured according to ASTM D1003 not higher than 20%, and/or a gloss measured according to ASTM D 2457 of at least 90.
  12. A method of forming a packaged article comprising the steps of: a. providing a multilayer film, the multilayer film comprising: i. at least one outer layer comprising at least 70% by weight of one or more of an ethylene/alpha-olefin copolymer; ii. and at least one inner layer being an abuse layer comprising a blend of: at least 1% by weight of an anhydride grafted elastomer selected from the group consisting of ethylene propylene diene monomer, ethylene propylene copolymer, styrene-ethylene-butylene-styrene, ethylene/octene copolymer and blends thereof, the anhydride grafted elastomer having a grafting level between 0.1-3.0 wt%.; and at least 25% by weight one or more polyamides; iii. at least 5%, 10%, 20%, 30%, 40% or 50% by weight of the multilayer film being of one or more polyamides; the multilayer film having a haze measured according to ASTM D1003 not higher than 20%, and/or a gloss measured according to ASTM D 2457 of at least 90; b. forming the film into a tube in a vertical form fill and seal apparatus; c. filling the tube with a food product; and d. closing the tube to form a sealed pouch containing the food product.
  13. A multilayer film comprising: a. a first inner layer; b. two abuse layers disposed on opposite surfaces of the first inner layer, the two abuse layers comprising a blend of: i. at least 1% by weight of a maleic anhydride grafted elastomer selected from the group consisting of ethylene propylene diene monomer, ethylene propylene copolymer, styrene-ethylene-butylene-styrene, ethylene/octene copolymer and blends thereof, the anhydride grafted elastomer having a grafting level between 0.1-3.0 wt%.; and ii. at least 25% by weight one or more polyamides; c. two tie layers each disposed on a surface of the respective abuse layer, each tie layer comprising a maleic anhydride modified ethylene/alpha-olefin copolymer; and d. two outer layers, each disposed on a surface of a respective tie layer, each outer layer comprising at least 70% by weight of one or more of an ethylene/alpha-olefin copolymer; at least 5%, 10%, 20%, 30%, 40% or 50% by weight of the multilayer film being of one or more polyamides; the multilayer film having a haze measured according to ASTM D1003 not higher than 20%, and/or a gloss measured according to ASTM D 2457 of at least 90.
  14. The multilayer film of claim 13, wherein the first inner layer is a barrier layer, the multilayer film have an oxygen transmission rate of no more than 150 cubic centimeters (at standard temperature and pressure) per square meter per day per 1 atmosphere of oxygen pressure differential measured at 0% relative humidity and 23 □ C as measured according to ASTM D-3985.
  15. The multilayer film of claim 13 wherein the two abuse layers comprising: i. at between 1-50%, 2-40%, 3-30%, 4-20% or 5-15% % by weight of an anhydride grafted elastomer selected from the group consisting of ethylene propylene diene monomer, ethylene propylene copolymer, styrene-ethylene-butylene-styrene, ethylene/octene copolymer and blends thereof; and ii. at least 50%, 60%, 70% or 80% by weight one or more polyamides.

Description

BACKGROUND The subject matter disclosed herein relates to multilayer films. More particularly, to multilayer films for food packaging. Nylon has been added to multilayer films to improve abuse and impact properties and to resist failures and leaking during packaging and distribution of food packaging. However, even with the inclusion of nylon into the multilayer film, failures of packaging are still evident. Failures can case body, seal, and pinhole failures that lead to leaking packages. In addition, nylon may become brittle, especially in cold and dry environments, which causes the film to crack when strained. WO2019/081175A1 discloses tough, flexible and non-heat shrinkable barrier laminate structures having a plurality of alternating extruded polymeric layers for food applications. The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter. BRIEF DESCRIPTION A multilayer film including at least one abuse layer. The abuse layer being a blend of one or more polyamides and an anhydride grafted elastomer. Anhydride grafted elastomers include ethylene propylene diene monomer, ethylene propylene copolymer, styrene-ethylene-butylene-styrene, ethylene/octene copolymer and blends thereof. A pouch for made from the multilayer film, a method for packaging a food product with the multilayer film are also disclosed. An advantage that may be realized in the practice of some disclosed embodiments of the multilayer film are reduced impact failure. The multilayer film comprises at least one outer layer comprising at least 70% by weight of one or more of an ethylene/alpha-olefin copolymer, and at least one inner layer being an abuse layer comprising a blend of: at least 1% by weight of an anhydride grafted elastomer selected from the group consisting of ethylene propylene diene monomer, ethylene propylene copolymer, styrene-ethylene-butylene-styrene, ethylene/octene copolymer and blends thereof, the anhydride grafted elastomer having a grafting level between 0.1-3.0 wt%; and at least 25% by weight one or more polyamides; at least 5%, 10%, 20%, 30%, 40% or 50% by weight of the multilayer film being of one or more polyamides, the multilayer film having a haze measured according to ASTM D1003 not higher than 20%, and/or a gloss measured according to ASTM D 2457 of at least 90. In another exemplary embodiment, a food package is disclosed. The food package comprises a food product; a pouch containing the food product, the pouch being made from a multilayer film comprising: at least one outer layer comprising at least 70% by weight of one or more of an ethylene/alpha-olefin copolymer; and at least one inner layer being an abuse layer comprising a blend of: at least 1% by weight of an anhydride grafted elastomer selected from the group consisting of ethylene propylene diene monomer, ethylene propylene copolymer, styrene-ethylene-butylene-styrene, ethylene/octene copolymer and blends thereof, the anhydride grafted elastomer having a grafting level between 0.1-3.0 wt%; and at least 25% by weight one or more polyamides; at least 5%, 10%, 20%, 30%, 40% or 50% by weight of the multilayer film being of one or more polyamides, the multilayer film having a haze measured according to ASTM D1003 not higher than 20%, and/or a gloss measured according to ASTM D 2457 of at least 90. In another exemplary embodiment, a method of forming a packaged article is disclosed. The method comprises the steps of a. providing a multilayer film, the multilayer film comprising: at least one outer layer comprising at least 70% by weight of one or more of an ethylene/alpha-olefin copolymer; and at least one inner layer being an abuse layer comprising a blend of: at least 1% by weight of an anhydride grafted elastomer selected from the group consisting of ethylene propylene diene monomer, ethylene propylene copolymer, styrene-ethylene-butylene-styrene, ethylene/octene copolymer and blends thereof, the anhydride grafted elastomer having a grafting level between 0.1-3.0 wt%; and at least 25% by weight one or more polyamides; at least 5%, 10%, 20%, 30%, 40% or 50% by weight of the multilayer film being of one or more polyamides, the multilayer film having a haze measured according to ASTM D1003 not higher than 20%, and/or a gloss measured according to ASTM D 2457 of at least 90. b. forming the film into a tube in a vertical form fill and seal apparatus; c. filling the tube with a food product; and d. closing the tube to form a sealed pouch containing the food product. In another exemplary embodiment a multilayer film is disclosed. The multilayer film comprises a first inner layer; two abuse layers disposed on opposite surfaces of the first inner layer, the two abuse layers comprising a blend of: at least 1% by weight of an anhydride grafted elastomer selected from the group consisting of ethylene propylene diene monomer, ethylene propylene copolymer,