Cellulose-fiber-dispersing polyolefin resin composite material, pellet and formed body using same, and production method for cellulose-fiber-dispersing polyolefin resin composite material

Patent metadata

Field	Value
Publication number	US-11261318-B2
Application number	US-202016797654-A
Country	US
Kind code	B2
Filing date	Feb 21, 2020
Priority date	Aug 23, 2017
Publication date	Mar 1, 2022
Grant date	Mar 1, 2022

Abstract

A cellulose-fiber-dispersing polyolefin resin composite material, containing a polyolefin resin containing a polypropylene resin, and a cellulose fiber dispersed in the polyolefin resin, in which a proportion of the cellulose fiber is 1 mass part or more and 70 mass parts or less in a total content of 100 mass parts of the polyolefin resin and the cellulose fiber, and the polyolefin resin satisfies the expression: Mz/Mw≥4, which is a ratio of Z-average molecular weight Mz to weight-average molecular weight Mw to be obtained by a gel permeation chromatography measurement;
a pellet or a formed body using this composite material; and a production method for the composite material.

First claim

The invention claimed is:

1. A cellulose-fiber-dispersing polyolefin resin composite material, comprising:
a polyolefin resin containing a polypropylene resin; and
a cellulose fiber dispersed in the polyolefin resin,
wherein a proportion of the cellulose fiber is 5 mass part or more and less than 50 mass parts in a total content of 100 mass parts of the polyolefin resin and the cellulose fiber,
wherein the polyolefin resin satisfies the expression: Mz/Mw≥4, which is a ratio of Z-average molecular weight Mz to weight-average molecular weight Mw to be obtained by a gel permeation chromatography measurement, and
wherein the weight average molecular weight Mw is in the range of 400,000 or more and 1,000,000 or less.

2. A cellulose-fiber-dispersing polyolefin resin composite material, comprising:
a polyolefin resin containing a polypropylene resin; and
a cellulose fiber dispersed in the polyolefin resin,
wherein a proportion of the cellulose fiber is 5 mass part or more and less than 50 mass parts in a total content of 100 mass parts of the polyolefin resin and the cellulose fiber,
wherein the polyolefin resin satisfies the expression: Mz/Mw≥4, which is a ratio of Z-average molecular weight Mz to weight-average molecular weight Mw to be obtained by a gel permeation chromatography measurement, and

wherein a melt flow rate (MFR) at a temperature of 230° C. and a load of 5 kgf is 0.05 to 50.0 g/10 min.

3. A cellulose-fiber-dispersing polyolefin resin composite material, comprising:
a polyolefin resin containing a polypropylene resin; and
a cellulose fiber dispersed in the polyolefin resin,
wherein a proportion of the cellulose fiber is 5 mass part or more and less than 50 mass parts in a total content of 100 mass parts of the polyolefin resin and the cellulose fiber,
wherein the polyolefin resin satisfies the expression: Mz/Mw≥4, which is a ratio of Z-average molecular weight Mz to weight-average molecular weight Mw to be obtained by a gel permeation chromatography measurement, and

comprising aluminum dispersed in the polyolefin resin,
wherein a content of the aluminum is 1 mass part or more and 40 mass parts or less based on a total content of 100 mass parts of the polyolefin resin and the cellulose fiber.

4. The cellulose-fiber-dispersing polyolefin resin composite material according to claim 3 , wherein a proportion of the number of aluminum having an X-Y maximum length of 1 mm or more in the number of aluminum having an X-Y maximum length of 0.005 mm or more is less than 1%.

5. The cellulose-fiber-dispersing polyolefin resin composite material according to claim 1 , comprising a cellulose fiber having a fiber length of 1 mm or more.

6. The cellulose-fiber-dispersing polyolefin resin composite material according to claim 1 , wherein a proportion occupied by the polypropylene resin in the polyolefin resin is 50 mass % or more.

7. The cellulose-fiber-dispersing polyolefin resin composite material according to claim 1 , wherein the cellulose-fiber-dispersing polyolefin resin composite material comprises an inorganic material, and a content of the inorganic material is 1 mass part or more and 100 mass parts or less based on 100 mass parts of the polyolefin resin.

8. The cellulose-fiber-dispersing polyolefin resin composite material according to claim 1 , wherein, in the cellulose-fiber-dispersing polyolefin resin composite material, water absorption ratio after the cellulose-fiber-dispersing polyolefin resin composite material is immersed into water at 23° C. for 20 days is 0.1 to 10%, and impact resistance after the cellulose-fiber-dispersing polyolefin resin composite material is immersed into water at 23° C. for 20 days is higher than impact resistance before the cellulose-fiber-dispersing polyolefin resin composite material is immersed thereinto.

9. The cellulose-fiber-dispersing polyolefin resin composite material according to claim 1 , wherein a moisture content is less than 1 mass %.

10. A pellet, which is produced by using the cellulose-fiber-dispersing polyolefin resin composite material according to claim 1 .

11. A formed body, which is produced by using the cellulose-fiber-dispersing polyolefin resin composite material according to claim 1 .

12. A method for producing the cellulose-fiber-dispersing polyolefin resin composite material according to claim 1 , the method comprising any of the following steps (I) to (V);
(I) melt-kneading a cellulose-fiber-adhering polyolefin thin film piece in the presence of water, subsequently mixing this melt-kneaded product with a polypropylene resin, and kneading the mixture, with the proviso that, in the cellulose-fiber-adhering polyolefin thin film piece, the amount of the cellulose fiber is smaller than the amount of the polyolefin resin as an average of the dry mass ratio;
(II) mixing a cellulose-fiber-adhering polyolefin thin film piece and a polypropylene resin, and melt-kneading the mixture in the presence of water, with the proviso that, in the cellulose-fiber-adhering polyolefin thin film piece, the amount of the cellulose fiber is smaller than the amount of the polyolefin resin as an average of the dry mass ratio;
(III) melt-kneading a polyolefin laminated paper and/or a beverage/food pack formed from this polyolefin laminated paper in the presence of water, subsequently mixing this melt-kneaded product with a polypropylene resin, and kneading the mixture;
(IV) mixing a polyolefin laminated paper and/or a beverage/food pack formed from this polyolefin laminated paper with a polypropylene resin, and melt-kneading the mixture in the presence of water; and
(V) mixing paper with a polypropylene resin, and melt-kneading the mixture in the presence of water;
wherein the melt-kneading in the steps (I) to (V) is carried out using a batch type closed kneading device having a stirring blade while satisfying the following condition (i) and/or condition (ii):
(i) the highest end-point temperature of melt-kneading is 280° C. or lower; and
(ii) the ratio of the Z average molecular weight Mz with respect to the weight average molecular weight Mw of the resulting composite material satisfies the expression: Mz/Mw≥4.

13. The production method for a cellulose-fiber-dispersing polyolefin resin composite material according to claim 12 , wherein the cellulose-fiber-adhering polyolefin thin film piece is a polyolefin thin film piece formed by cellulose fibers and aluminum adhering thereto, and the polyolefin laminated paper has an aluminum thin film layer.

14. The production method for a cellulose-fiber-dispersing polyolefin resin composite material according to claim 12 , wherein the melt kneading is performed in the presence of water in a subcritical state.

15. The production method for a cellulose-fiber-dispersing polyolefin resin composite material according to claim 12 , wherein the cellulose-fiber-dispersing polyolefin resin composite material comprises aluminum dispersed therein, and wherein, in the cellulose-fiber-dispersing polyolefin resin composite material, a proportion of the number of aluminum having an X-Y maximum length of 1 mm or more in the number of aluminum having an X-Y maximum length of 0.005 mm or more is less than 1%.

16. A pellet, which is produced by using the cellulose-fiber-dispersing polyolefin resin composite material according to claim 2 .

17. A pellet, which is produced by using the cellulose-fiber-dispersing polyolefin resin composite material according to claim 3 .

18. A formed body, which is produced by using the cellulose-fiber-dispersing polyolefin resin composit

Assignees

• Furukawa Electric Co Ltd

Inventors

• Sawada Yuka
• Hara Hidekazu
• Hiroishi Jirou
• Tazuke Masami
• Suzuki Toshihiro

Classifications

• C08L23/12 Primary

  Polypropene · CPC title

• C08L1/02

  Cellulose; Modified cellulose · CPC title

• C08J3/20

  Compounding polymers with additives, e.g. colouring · CPC title

• C08J2401/02

  Cellulose; Modified cellulose · CPC title

• B29B9/14

  fibre-reinforced · CPC title