Polyglycolic acid-based resin composition and shaped product thereof
A polyglycolic acid-based resin composition is formed by adding a relatively small amount of aromatic polyester resin to a polyglycolic acid resin. The thus-formed composition is provided with remarkably improved moisture resistance stability and hot-melt processability, and further improved stretchability, while retaining the excellent properties as represented by gas barrier property of the polyglycolic acid resin. As a result of stretching by utilizing the improved stretchability, a shaped product having an improved transparency can be obtained.
1. A polyglycolic acid-based resin composition, comprising: 99 to 60 wt. % of a polyglycolic acid resin and 1 to 40 wt. % of an aromatic polyester resin.
2. A resin composition according to claim 1 , comprising 90–70 wt. % of the polyglycolic acid resin and 10–30 wt. % of the aromatic polyester resin.
3. A resin composition according to claim 1 , containing a thermal stabilizer of the polyglycolic acid resin.
4. A resin composition according to claim 3 , wherein the thermal stabilizer is at least one compound selected from the group consisting of heavy metal-deactivating agents, phosphoric acid esters including a pentaerythritol skeleton, phosphor compounds having at least one hydroxyl group and at least one alkyl ester group, and metal carbonate salts.
5. A resin composition according claim 3 , including the polyglycolic acid resin preliminarily melt-mixed with the thermal stabilizer.
6. A resin composition according to claim 1 , wherein the aromatic polyester resin is an aromatic polyester copolymer.
7. A shaped product comprising a polyglycolic acid-based resin composition according to claim 1 .
8. A shaped product according to claim 7 , having a multi-layer structure.
9. A shaped product according to claim 7 , having a form of film.
10. A shaped product according to claim 9 , having a multi-layer structure including at least one stretched layer.
11. A shaped product according to claim 10 , including two or more co-extruded layers.
12. A shaped product according to claim 10 , wherein the stretched layer has been stretched at a stretching ratio of at least 2 times in at least one direction.
13. A shaped product according to claim 12 , wherein the stretched layer has been stretched at an weal stretching ratio of at least 4 times.
14. A shaped product according to claim 12 , wherein the stretched layer has been stretched at a stretching ratio of ca. 3–4 times in at least one direction.
15. A shaped product according to claim 13 , wherein the stretched layer has been stretched at an weal stretching ratio of ca. 9–16 times.