Poly(3-hydroxyalkanoate) resin composition

Patent metadata

Field	Value
Publication number	US-11053386-B2
Application number	US-202016740572-A
Country	US
Kind code	B2
Filing date	Jan 13, 2020
Priority date	Jul 24, 2017
Publication date	Jul 6, 2021
Grant date	Jul 6, 2021

Abstract

Provided are a resin composition containing poly(3-hydroxyalkanoate), the resin composition enabling a film or a sheet to be stably produced under practical processing conditions by inflation molding; and a method for producing the resin composition. The resin composition includes 100 parts by weight of poly(3-hydroxyalkanoate) and 5 to 15 parts by weight of an ester compound, and having a ratio of 3.5×10 −2 to 4.8×10 −2 (sec/[Pa·s]) between a melt viscosity (Pa·s) and a drawdown time (sec).

First claim

The invention claimed is:

1. A resin composition, comprising:
100 parts by weight of poly(3-hydroxyalkanoate); and
5 to 15 parts by weight of an ester compound,
wherein a ratio of a melt viscosity (Pa·s) to a drawdown time (sec) of the resin composition is from 4.0×10 −2 to 4.7×10 −2 (sec/[Pa·s]),
wherein the melt viscosity is an apparent melt viscosity (η) calculated from the following formula (1), wherein F is a load measured with a capillary rheometer in extrusion of the resin composition molten at a volume flow rate (Q) of 0.716 cm 3 /ruin and a shear rate of 122 sec −1 from an orifice having a radius (d) of 0.05 cm and a capillary length (l) of 1 cm and connected to the tip of a barrel having a barrel set temperature of 170° C. and a radius (D) of 0.4775 cm, and the drawdown time is a time required for the resin composition to fall by 20 cm after being discharged from the orifice in measurement of the melt viscosity:

η
=

π
⁡

(

F
/
π

⁢

⁢

D
2

)

⁢

d
4

8
⁢

⁢
Ql

.

Formula
⁢

⁢
1

2. The resin composition according to claim 1 , wherein the melt viscosity is from 800 to 1600 (Pa·s).

3. The resin composition according to claim 1 , wherein the drawdown time is from 30 to 60 (sec).

4. The resin composition according to claim 1 , wherein the ester compound has no radical-reactive functional group.

5. The resin composition according to claim 1 , wherein the poly(3-hydroxyalkanoate) is at least one selected from the group consisting of poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(3-hydroxybutyrate-co-3-hydroxyhexanoate, poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-3-hydroxyhexanoate), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyoctanoate) and poly(3-hydroxybutyrate-co-3-hydroxydecanoate).

6. The resin composition according to claim 1 , wherein the ester compound is at least one selected from the group consisting of a glycerin ester-based compound, a dibasic acid ester-based compound, an adipate ester-based compound, a polyether ester-based compound and an isosorbide ester-based compound.

7. A molded article obtained by molding the resin composition of claim 1 .

8. The molded article according to claim 7 , wherein the molded article is a film or a sheet.

9. The molded article according to claim 7 , wherein the molded article is a film having a thickness of 30 μm or less.

10. A method for producing the resin composition of claim 1 , the method comprising:
melting and kneading 100 parts by weight of poly(3-hydroxyalkanoate) from 5 to 15 parts by weight of an ester compound having no radical-reactive functional group and from 0.01 to 0.6 parts by weight of an organic peroxide at a resin temperature of from 155° C. to 175° C.

11. The method according to claim 10 , wherein the melting and kneading is performed such that the mixture is retained in an extruder for 60 seconds to 300 seconds.

12. A method for producing a film or a sheet, comprising:
forming a film or a sheet by subjecting the resin composition of claim 1 to inflation molding.

13. The resin composition according to claim 1 , wherein the poly(3-hydroxyalkanoate) has a weight average molecular weight of from 50,000 to 3,000,000.

14. The resin composition according to claim 1 , further comprising:
250 parts by weight or less of a biodegradable resin other than the poly(3-hydroxyalkanoate).

15. The resin composition according to claim 1 , comprising from 8 to 11 parts by weight of the ester compound.

16. The resin composition according to claim 1 , which is obtained by melting and kneading 100 parts by weight of the poly(3-hydroxyalkanoate), from 0.01 to 0.6 parts by weight of an organic peroxide and from 5 to 15 parts by weight of the ester compound in an extruder.

Assignees

• Kaneka Corp

Inventors

• Koyama Ryohei
• Okura Tetsuo

Classifications

• B29C49/0005

  characterised by the material · CPC title

• B29C49/0691

  using sheet like material, e.g. sheet blow-moulding from joined sheets · CPC title

• C08G63/06

  derived from hydroxycarboxylic acids · CPC title

• C08K5/11

  of acyclic polycarboxylic acids · CPC title

• C08L2203/16

  used for films · CPC title