Biodegradable starch-based blown films
AssigneeThe United States of America as represented by the Secretary of Agriculture
InventorsFelix H. Otey, Richard P. Westhoff
Life of this patent
Estimating the term…
Abstract
Film-forming formulations comprising starch, ethylene acrylic acid copolymer, and optionally polyethylene, can be blown into films upon neutralization of a portion of the copolymer acid functionality. The resultant biodegradable films have potential application as agricultural mulch, garbage bags, and various types of packaging.
Claims10
In a method of producing a flexible, self-supporting, and biodegradable film wherein a mixture comprising a partially or completely gelatinized starchy material in an amount up to 60% by weight and an ethylene acrylic acid copolymer is converted into a plasticized matrix and then shaped into said film, the improvement comprising the following steps:
- a. incorporating into said matrix a neutralizing agent selected from the group of aqueous ammonia and anhydrous ammonia;
- b. adjusting the moisture content of said matrix to within the range of about 2-10% based on the weight of the matrix;
- and
- c. extrusion blowing said ammoniated and moisture-adjusted matrix into a film.
Dependencies are inferred from the claim text.