Polymer compositions for the production of articles of biodegradable plastics material and methods of their preparation
AssigneeNovamont S.p.A.
InventorsCatia Bastioli, Vittorio Bellotti, Luciano Del Guidice, Roberto Lombi
Life of this patent
Estimating the term…
Abstract
Polymer compositions useful for the production of articles of biodegradable plastics material with improved biodegradability include destructed starch and a polymer selected from the group consisting of ethylene-vinyl alcohol, polyvinyl alcohol and mixtures thereof wherein at least a portion of the said polymer is modified by the substitution of from 0.1 to 5 molar % of the functional alcohol groups in the polymer chain by X groups in which X is an oxo or an alkyl carbonyl group in which the alkyl group contains from 1 to 4 carbon atoms.
Claims18
A polymer composition useful for the production of articles of biodegradable plastics material, including a destructured starch and a synthetic polymer selected from the group consisting of ethylene-vinyl alcohol, and polyvinyl alcohol and mixtures thereof, wherein at least a portion of said polymers is modified by the substitution of from 0.1 to 5 molar % of the functional alcohol groups in the polymer chain by X groups in which X is an oxo group or an alkyl carbonyl group in which the alkyl group contains from 1 to 4 carbon atoms.
A method for the preparation of a polymer composition usable for the production of articles of biodegradable plastics material, comprising the step of:
- mixing starch and a synthetic polymer selected from the group consisting of ethylene-vinyl alcohol, polyvinyl alcohol and mixtures thereof, wherein at least a portion of said polymers is modified by the substitution of from 0.1 to 5 molar % of the functional alcohol groups in the polymer chain by X groups in which X is an oxo group or an alkyl carbonyl group in which the alkyl group contains from 1 to 4 carbon atoms, wherein the weight ratio between the starch and total amount of synthetic polymer is of from 19:1 to 1:19, with a quantity of a high-boiling plasticizer of from 0.05 to 100% of the weight of the starch, optional in the presence of a destructuring agent selected from the group consisting of urea, alkaline-earth and alkali metal hydroxides, in an extruder which is heated to a temperature and for a period of time sufficient to bring about the destructuring of the starch.
Dependencies are inferred from the claim text.