Process for producing articles formed with biodegradable materials and strength characteristics of the same

Abstract

Described herein are strength characteristics and biodegradation of articles produced using one or more petrochemical-based polymers and one or more carbohydrate-based polymers. A compatibilizer can optionally be included in the article. In some cases, the article can include a film or bag.

1 . A process comprising:
 providing one or more polymeric materials;   providing one or more starch-based polymeric materials formed from a mixture of starches including a first starch and a second starch;   mixing the one or more polymeric materials and the one or more starch-based polymeric materials to produce a mixture of materials;   heating the mixture of materials; and   producing an article using the mixture of materials, the article having a strength value that is greater than: (i) a strength value of a first article including the polymeric material and a first starch-based polymeric material formed from a single starch that is the first starch, and (ii) a second strength value of a second article including the polymeric material and a second starch-based polymeric material formed from a single starch that is the second starch.   
     
     
         2 . The process of  claim 1 , wherein producing the article using the mixture of materials includes extruding the mixture of materials to produce an extruded object. 
     
     
         3 . The process of  claim 2 , wherein the process further includes injecting a gas into the extruded object, the object comprising a film, wherein the film has a dart drop impact test value of at least 200 g for a 1 mil thick film. 
     
     
         4 . The process of  claim 3 , wherein the film has a dart drop impact test value of at least 225 g for a 1 mil thick film. 
     
     
         5 . The process of  claim 3 , wherein the film has a dart drop impact test value from about 245 g to about 350 g for a 1 mil thick film. 
     
     
         6 . The process of  claim 1 , wherein:
 the mixture of materials further comprises one or more compatibilizers; and   the mixture of materials includes:
 from about 10% by weight to about 40% by weight of the one or more starch-based polymeric materials, from about 60% by weight to about 89% by weight of the one or more polymeric materials; and 
 from about 1% by weight to about 9% by weight of the one or more compatibilizers. 
   
     
     
         7 . The process of  claim 1 , wherein the article includes a film having a thickness from about 0.8 mil to about 2 mils. 
     
     
         8 . The process of  claim 1 , wherein the polymeric material comprises a polyolefin-based polymeric material. 
     
     
         9 . The process of  claim 1 , wherein the polymeric material comprises at least one of polyethylene, polypropylene, polystyrene, high impact polystyrene, nylon, polymethylpentene, or polybutene. 
     
     
         10 . The process of  claim 9 , wherein the polymeric material comprises a polyethylene, the polyethylene comprising at least one of ultra-high-molecular-weight polyethylene, ultra-low-molecular-weight polyethylene, high-molecular-weight polyethylene, high-density polyethylene, high-density cross-linked polyethylene, cross-linked polyethylene, medium-density polyethylene, linear low-density polyethylene, low-density polyethylene, or very-low-density polyethylene. 
     
     
         11 . The process of  claim 1 , wherein the heating is to a temperature in a range from about 120° C. to about 180° C. 
     
     
         12 . The process of  claim 1 , wherein the starch-based polymeric material is formed from the first starch, the second starch, and one or more plasticizers. 
     
     
         13 . The process of  claim 1 , wherein the mixture of the one or more polymeric materials and the one or more starch-based polymeric materials further comprises a compatibilizer. 
     
     
         14 . The process of  claim 13 , wherein the compatibilizer is present in an amount of about 3% by weight to about 7% by weight of the mixture. 
     
     
         15 . The process of  claim 1 , wherein the first starch is derived from one of potato, corn, or tapioca; and the second starch is derived from a different one of potato, corn, or tapioca. 
     
     
         16 . The process of  claim 1 , wherein the starch-based polymeric material is present in an amount from about 20% by weight to about 30% by weight of the article and the polymeric material is a polyolefin-based polymeric material that is present in an amount from about 65% by weight to about 75% by weight of the article. 
     
     
         17 . The process of  claim 1 , wherein the first starch comprises at least about 50% by weight of the mixture of starches, and the second starch comprises at least 5% by weight of the mixture of starches. 
     
     
         18 . The process of  claim 1 , wherein the second starch comprises about 10% by weight of the mixture of starches. 
     
     
         19 . The process of  claim 1 , wherein:
 the starch-based polymeric material is formed from a mixture of the first starch, the second starch and a third starch;   the third starch comprises at least about 5% by weight of the mixture of starches.   
     
     
         20 . The process of  claim 1 , wherein the article has a tensile elongation at break value in a machine direction that is greater than a tensile elongation at break value in the machine direction of a comparative article formed from the polymeric material alone that is free of starch-based polymeric materials.