Poly(lactic acid) resin composition and molded product comprising same

Patent metadata

Field	Value
Publication number	US-11118051-B2
Application number	US-201716081998-A
Country	US
Kind code	B2
Filing date	Jan 24, 2017
Priority date	Mar 24, 2016
Publication date	Sep 14, 2021
Grant date	Sep 14, 2021

Abstract

The present invention relates to a polylactic acid resin composition and a molded product using same. Since the polylactic acid resin composition according to the present invention has excellent environmental friendliness and biodegradability, has excellent heat resistance characteristics due to high heat deformation temperature (HDT), and may be injection molded within a commercially reasonable cycle time due to high crystallinity and crystallization rate, it is suitable for the preparation of a molded product.

First claim

The invention claimed is:

1. A polylactic acid resin composition comprising:
a polylactic acid resin which includes a hard segment including a polylactic acid repeating unit of the following Formula 1, and a soft segment including a polyurethane polyol repeating unit in which polyether-based polyol repeating units of the following Formula 2 are linearly linked via a urethane bond;
a poly-D-lactic acid (PDLA) resin as a nucleating agent; and
talc:

wherein, in Formula 1, n is an integer of 700 to 5,000; and
in Formula 2, A is a linear or branched alkylene group having 2 to 5 carbon atoms, and m is an integer of 10 to 100;
wherein the polylactic acid resin composition has a heat deformation temperature (HDT) of 100° C. or more; and
wherein the polylactic acid resin is a block copolymer in which a terminal carboxyl group of the polylactic acid repeating unit included in the hard segment and a terminal hydroxyl group of the polyurethane polyol repeating unit are linked via an ester bond.

2. The polylactic acid resin composition of claim 1 , wherein the polylactic acid resin composition comprises 60 wt % to 95 wt % of the polylactic acid resin, 1 wt % to 20 wt % of the poly-D-lactic acid resin, and 1 wt % to 20 wt % of the talc.

3. The polylactic acid resin composition of claim 2 , wherein the polylactic acid resin composition comprises 80 wt % to 95 wt % of the polylactic acid resin, 1 wt % to 10 wt % of the poly-D-lactic acid resin, and 1 wt % to 15 wt % of the talc.

4. The polylactic acid resin composition of claim 1 , wherein the polylactic acid resin has a number-average molecular weight of 50,000 to 200,000 and a weight-average molecular weight of 100,000 to 400,000.

5. The polylactic acid resin composition of claim 1 , wherein the polylactic acid resin has a glass transition temperature (Tg) of 20° C. to 80° C. and a melting temperature (Tm) of 150° C. to 180° C.

6. The polylactic acid resin composition of claim 1 , wherein the polylactic acid resin comprises 65 wt % to 95 wt % of the hard segment and 5 wt % to 35 wt % of the soft segment.

7. The polylactic acid resin composition of claim 1 , wherein the polylactic acid repeating unit is a poly-L-lactic acid repeating unit.

8. The polylactic acid resin composition of claim 1 , wherein the polyurethane polyol repeating units are linearly linked via a urethane bond which is formed by a reaction of a terminal hydroxyl group of the polyether-based polyol repeating unit with an isocyanate group of a diisocyanate compound.

9. The polylactic acid resin composition of claim 8 , wherein a reaction molar ratio of the terminal hydroxyl group of the polyether-based polyol repeating unit to the isocyanate group of the diisocyanate compound is in a range of 1:0.50 to 1:0.99.

10. The polylactic acid resin composition of claim 1 , wherein the poly-D-lactic acid resin has a weight-average molecular weight of 100,000 to 400,000.

11. A molded product comprising the polylactic acid resin composition of claim 1 .

12. The molded product of claim 11 , wherein the molded product is automatically injection molded by being cooled at a temperature of 100° C. to 150° C. for 10 seconds to 35 seconds.

13. The molded product of claim 11 , wherein the molded product has a heat deformation temperature of 100° C. to 150° C.

Assignees

• Sk Chemicals Co Ltd

Inventors

• Kim Min-Young
• Kim Tae-Young
• Hwang Jeoung-Jun
• Chung Jae-Il

Classifications

• Y02W90/10

  Bio-packaging, e.g. packing containers made from renewable resources or bio-plastics · CPC title

• C08G63/08 Primary

  Lactones or lactides · CPC title

• C08L2205/025

  containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure · CPC title

• C08L67/04 Primary

  Polyesters derived from hydroxycarboxylic acids, e.g. lactones (C08L67/06 takes precedence) · CPC title

• B29K2067/046

  PLA, i.e. polylactic acid or polylactide · CPC title