Method for reinforcing a thermoplastic resin composition

Patent metadata

Field	Value
Publication number	US-9902813-B2
Application number	US-201615386883-A
Country	US
Kind code	B2
Filing date	Dec 21, 2016
Priority date	Oct 10, 2012
Publication date	Feb 27, 2018
Grant date	Feb 27, 2018

Abstract

The present invention is directed to plant fiber-reinforced thermoplastic compositions and a method for reinforcing thermoplastic resins. The present invention provides a use for the cellulose portion of a plant material, which is the portion left over after processing the selected plant materials to separate the hemi-cellulose and lignin from the cellulose.

First claim

We claim:

1. A method for reinforcing a thermoplastic resin composition comprising:
a) providing an amount of cellulose fibers obtained by the separation of the cellulose fiber fraction from hemi-cellulose and lignin fractions of a natural plant material; and
b) blending from about 1 to about 60 weight percent of the cellulose fibers based on the weight of the composition with a thermoplastic resin, the cellulose fibers having a porous surface obtained by the mechanical shearing and subsequent chemical separation of the cellulose fiber fraction from hemi-cellulose and lignin fractions of a natural plant material.

2. The method of claim 1 wherein the natural plant material is selected from the group consisting of natural fibrous plant materials including a) seed fiber plants, linters, cotton, kapok and poplar down, b) bast fiber plants, sclerenchyma fiber plants, bamboo fiber plants, (stinging) nettles, hemp, jute, linen or flax, and ramie, c) hard fiber plants, sisal, kenaf and manila, d) coir, and e) grasses.

3. The method of claim 1 wherein the cellulose fibers are formed of at least 95% pure cellulose fibers.

4. The method of claim 1 wherein the thermoplastic resin is selected from the group consisting of polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyacryl nitrite, polyamides, polyesters, polyacrylates and mixtures thereof.

5. The method of claim 1 wherein the step of providing the cellulose fibers comprises:
a) mechanically separating core tissue fibers from outer plant fibers; and
b) chemically separating the cellulose fibers from hemi-cellulose and lignin fractions of the core tissue fibers.

6. The method of claim 5 wherein the step of mechanically separating the outer plant fibers from the core tissue fibers comprises shearing the outer plant fibers from the core tissue fibers to minimize damage to the core tissue fibers.

7. The method of claim 1 wherein the step of blending the cellulose fibers with the thermoplastic resin comprises mixing the cellulose fibers and the thermoplastic resin in parallel screw mixing device to minimize breakage of the cellulose fibers and the residence time of the fibers and resin in the mixing device.

8. The method of claim 1 wherein the step of blending the cellulose fibers with the thermoplastic resin comprises forming molecular bonds between the cellulose fibers and the thermoplastic resin.

Assignees

• Cnh Ind Canada Ltd

Inventors

• Henry James
• Panigrahi Satyanarayan
• Kushwaha Radhey Lal

Classifications

• C08G81/02 Primary

  at least one of the polymers being obtained by reactions involving only carbon-to-carbon unsaturated bonds · CPC title

• C08L1/02 Primary

  Cellulose; Modified cellulose · CPC title

• C08L97/02

  Lignocellulosic material, e.g. wood, straw or bagasse {(manufacture of articles made from lignocellulosic material by dry processes B27N)} · CPC title

• C08L77/00

  Compositions of polyamides obtained by reactions forming a carboxylic amide link in the main chain (of polyhydrazides C08L79/06; of polyamideimides or polyamide acids C08L79/08); Compositions of derivatives of such polymers · CPC title

• C08L67/00

  Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain (of polyester-amides C08L77/12; of polyester-imides C08L79/08); Compositions of derivatives of such polymers · CPC title