Reinforced organic natural fiber composites

Patent metadata

Field	Value
Publication number	US-9988504-B2
Application number	US-201415126311-A
Country	US
Kind code	B2
Filing date	Dec 11, 2014
Priority date	Mar 28, 2014
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

A reinforced organic natural fiber composite material having a lambda value in the range 15-35 mW/m·K is disclosed which comprises 25-85% by weight hydrophobic nanoporous particles calculated on the total weight of the composite material, at least 10% by weight organic natural fibers having isocyanate reactive groups calculated on the total weight of the composite material and 1-15% by weight binder selected from a polyurea/polyurethane comprising binder made from emulsifiable polyisocyanate, water and surfactants.

First claim

The invention claimed is:

1. A reinforced organic natural fiber composite material having a lambda value in the range 15-35 mW/mK, said composite material comprising:
25-85% by weight of hydrophobic nanoporous particles calculated on the total weight of the composite material, and
at least 10% by weight of organic natural fibers having isocyanate reactive groups calculated on the total weight of the composite material, and
1-15% by weight of binder calculated on the total weight of the composite material,
wherein, the binder is a polyurea/polyurethane binder made from emulsifiable polyisocyanate, water, and surfactants.

2. The reinforced organic natural fiber composite material according to claim 1 wherein the composite material comprises 10-70% by weight of organic natural fibers having isocyanate reactive groups calculated on the total weight of the composite material.

3. The reinforced organic natural fiber composite material according to claim 1 wherein the hydrophobic nanoporous particles are aerogel particles based on oxides and/or metal oxides wherein the metal of the metal oxides is selected from the group consisting of alumina, titanium, and/or zirconium oxides.

4. The reinforced organic natural fiber composite material according to claim 1 wherein the hydrophobic nanoporous particles have the following parameters:
Porosity: 50 to 99%,
Density: lower than 300 kg/m 3 ,
Particle diameter: from 0.001 to 10 mm,
Pore diameter: 0.1 to 500 nm.

5. The reinforced organic natural fiber composite material according to claim 1 wherein the hydrophobic nanoporous particles are aerogel particles which are organo-modified with hydrophobic groups, are based on silicon dioxide (SiO 2 ) and have lambda values under atmospheric pressure in the range 9-12 mW/mK at 25° C. together with a low density around 140 kg/m 3 .

6. The reinforced organic natural fiber composite material according to claim 1 wherein the hydrophobic nanoporous particles have hydrophobic groups on their pore surface selected from trisubstituted silyl groups of general formula —Si(R) 3 where each R is independently a nonreactive organic moiety selected from the group consisting of such as C1-C18 alkyl, C6-C14 aryl, methyl, ethyl, cyclohexyl, or phenyl, and wherein such moiety may be additionally substituted with functional groups.

7. The reinforced organic natural fiber composite material according to claim 1 wherein the organic natural fibers comprise wood or bamboo fibers.

8. The reinforced organic natural fiber composite material according to claim 1 wherein the binder comprises emulsifiable polyisocyanate which is a reaction product of >95 wt % polyisocyanates and <5 wt % of monoalkyl ethers and/or polyethylene glycols calculated on the total weight of the emulsifiable polyisocyanate.

9. The reinforced organic natural fiber composite material according to claim 1 wherein the binder comprises up to maximum 5 weight % surfactants calculated on the total weight of surfactant and water.

10. A process for making the reinforced organic natural fiber composite material according to claim 1 , said process comprising the following steps:
a) providing the binder comprising water, emulsifiable polyisocyanate, and surfactants, and
b) providing the organic natural fibers, and then
c) mixing the binder and organic natural fibers to obtain a mixture comprising the organic natural fibers and the binder, and then
d) adding the hydrophobic nanoporous particles to the mixture obtained in c) and mixing to obtain a homogenous mixture comprising the hydrophobic nanoporous particles, the organic natural fibers and the binder, and then
e) curing and drying the mixture in a compression mold to obtain the reinforced organic natural fiber composite material.

11. The process according to claim 10 wherein the step of curing and drying is performed by a thermal treatment at temperatures of at least 50° C. and/or via microwave radiation.

12. The process according to claim 11 wherein the step of curing and drying is performed in a compression mold suitable for encapsulating 3D shaped objects.

13. The reinforced organic natural fiber composite material according to claim 3 wherein the alumina, titanium, and/or zirconium oxides are organo-modified.

Assignees

• Huntsman Int Llc

Inventors

• Joncheray Thomas Julien
• Vandenbroeck Jan

Classifications

• C08J2375/02

  Polyureas · CPC title

• C08G18/80

  Masked polyisocyanates · CPC title

• C08J2475/04

  Polyurethanes · CPC title

• C08G18/283

  Compounds containing ether groups, e.g. oxyalkylated monohydroxy compounds · CPC title

• C08L75/04

  Polyurethanes · CPC title