Process for the preparation of biodegradable plastic films

Patent metadata

Field	Value
Publication number	US-11242437-B2
Application number	US-201816477041-A
Country	US
Kind code	B2
Filing date	Jan 10, 2018
Priority date	Jan 17, 2017
Publication date	Feb 8, 2022
Grant date	Feb 8, 2022

Abstract

A process for the manufacture of biodegradable plastic films in aqueous environment, starting from vegetal wastes in powder form includes dissolution at a temperature lower than 50° C. of waste material in form of a powder in an aqueous solution of hydrochloric acid, and transfer of the aqueous solution in a casting mould and evaporation of the aqueous solution, to yield the biodegradable plastic film. The total concentration of the hydrochloric acid is equal to or lower than 5% by weight. The aqueous solution may include acetic acid. The aqueous solution may also be filtered or centrifuged and/or subjected to dialysis against pure water.

First claim

The invention claimed is:

1. A process for preparing a biodegradable plastic film starting from a vegetal waste material, said process comprising the following steps:
i) dissolution at a temperature lower than 50° C. of said vegetal waste material in a form of a powder in an aqueous solution of hydrochloric acid, optionally added with acetic acid, wherein the total concentration of acid is equal to or lower than 5% by weight; and
ii) transfer the solution obtained in step i), optionally filtered or centrifuged and/or subjected to dialysis against pure water, in a casting mold and evaporation of said aqueous solution, to yield said biodegradable plastic film.

2. The process according to claim 1 , wherein said dissolution in step i) is completed in a time ranging between 1 and 18 hours.

3. The process according to claim 1 , wherein said dissolution is carried out at a temperature ranging between 15° C. and 40° C.

4. The process according to claim 1 , wherein said powder consists of particles with average size ranging between 10 and 500 micrometres.

5. The process according to claim 1 , wherein said powder is dried before said dissolution.

6. The process according to claim 1 , wherein said vegetal waste material is selected from the group consisting of wastes of carrot, radicchio, parsley stems and cauliflower stems.

7. The process according to claim 1 , wherein said vegetal waste material is dissolved in said aqueous solution in step i) in a concentration ranging between 4 and 10% by weight with respect to the weight of the aqueous solution.

8. The process according to claim 1 , wherein the biodegradable plastic film obtained in step ii) is subjected to washing with water.

Assignees

• Fondazione St Italiano Tecnologia

Inventors

• Perotto Giovanni
• Bayer Ilker
• Athanasiou Athanasia

Classifications

• C08H8/00

  Macromolecular compounds derived from lignocellulosic materials {(pretreatment thereof B27N)} · CPC title

• C08L97/02

  Lignocellulosic material, e.g. wood, straw or bagasse {(manufacture of articles made from lignocellulosic material by dry processes B27N)} · CPC title

• C08J2497/02

  Lignocellulosic material, e.g. wood, straw or bagasse · CPC title

• C08J2399/00

  Characterised by the use of natural macromolecular compounds or of derivatives thereof not provided for in groups C08J2301/00 - C08J2307/00 or C08J2389/00 - C08J2397/00 · CPC title

• C08J5/18 Primary

  Manufacture of films or sheets · CPC title