Polylactic acid composition

Patent metadata

Field	Value
Publication number	US-10626246-B2
Application number	US-201515124749-A
Country	US
Kind code	B2
Filing date	Feb 17, 2015
Priority date	Mar 11, 2014
Publication date	Apr 21, 2020
Grant date	Apr 21, 2020

Abstract

A polylactic acid composition of a dispersion structure using, as a matrix, a lowly crystalline or amorphous polylactic acid having a crystallinity of not more than 40%, the matrix containing, as a pulverization promotor dispersed therein, an organically modified polysaccharide or a lamellar silicate that is swollen or that is treated to be swollen.
The polylactic acid composition has excellent hydrolysable capability and property of being mechanically pulverized.

First claim

The invention claimed is:

1. A mechanically pulverized material of a polylactic acid composition using, as a matrix, a polylactic acid having a crystallinity of not more than 40%, the matrix containing a pulverization promotor dispersed therein, wherein:
said pulverized material is a granular material having a grain size of not more than 300 μm, the granules therein having ratios of the smallest diameter/largest diameter of not less than 0.5,
said pulverization promotor is a lamellar silicate that is swollen or that is treated to be swollen, and is contained in an amount of 1 to 10 parts by weight per 100 parts by weight of said polylactic acid,
said polylactic acid composition is a melt-kneaded product of the polylactic acid and the pulverization promotor,
said polylactic acid has a crystallinity of not less than 5%, and
a surface of said lamellar silicate that is swollen or that is treated to be swollen is treated with a salt of a fatty acid selected from the group consisting of a Ca salt, a Zn salt, a Mg salt or a Ba salt of a fatty acid.

2. The mechanically pulverized material of a polylactic acid composition as claimed in claim 1 , wherein as the polylactic acid, use is made of a DL-isomer in which an L-isomer and a D-isomer are contained at a weight ratio (L/D) in a range of 98/2 to 2/98.

3. The mechanically pulverized material of a polylactic acid composition as claimed in claim 1 , wherein the lamellar silicate that is the pulverization promotor is a montmorillonite in which organic cations are introduced.

4. The mechanically pulverized material of a polylactic acid composition as claimed in claim 1 , wherein the polylactic acid composition is used for the preparation of an aqueous dispersion solution for drilling.

5. The mechanically pulverized material of a polylactic acid composition as claimed in claim 1 , wherein the polylactic acid and the pulverization promotor are melt-kneaded at a temperature not lower than a melting point of the polylactic acid.

6. The mechanically pulverized material of a polylactic acid composition as claimed in claim 1 , wherein said polylactic acid has a crystallinity of from 5 to 38%.

7. The mechanically pulverized material of a polylactic acid composition as claimed in claim 1 , wherein a surface of said lamellar silicate that is swollen or that is treated to be swollen is treated with a salt of a fatty acid selected from the group consisting of a Ca salt, a Zn salt, a Mg salt or a Ba salt of stearic acid, palmitic acid or lauric acid.

8. The mechanically pulverized material of a polylactic acid composition as claimed in claim 1 , wherein the pulverization promotor comprises a lamellar silicate that is treated to be swollen.

9. The mechanically pulverized material of a polylactic acid composition as claimed in claim 8 , wherein a surface of said lamellar silicate that is treated to be swollen is treated with a salt of a fatty acid selected from the group consisting of a Ca salt, a Zn salt, a Mg salt or a Ba salt of stearic acid, palmitic acid or lauric acid.

Assignees

• Toyo Seikan Group Holdings Ltd

Inventors

• Yoshikawa Seishi
• Yamada Toshiki
• Katayama Tsutaki

Classifications

• C08L2201/06

  Biodegradable · CPC title

• C08L1/02

  Cellulose; Modified cellulose · CPC title

• C08K3/346

  Clay · CPC title

• C08K9/04 Primary

  Ingredients treated with organic substances {(treated with macromolecular compounds C08K9/08)} · CPC title

• C08K9/00

  Use of pretreated ingredients · CPC title