Moldable uncured nonwoven composite and molded cured composite

Patent metadata

Field	Value
Publication number	US-10239234-B2
Application number	US-201615165473-A
Country	US
Kind code	B2
Filing date	May 26, 2016
Priority date	May 26, 2016
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

A process for forming a moldable, uncured nonwoven composite containing forming a structural nonwoven layer, at least partially impregnating the structural nonwoven layer with an uncured, water-based thermosetting resin having a cure temperature of at least about 160° C., and at least partially drying the uncured, wet nonwoven composite such that the temperature at the inner plane is less than about 130° C. forming an moldable, uncured composite. The structural nonwoven layer contains a plurality of bi-component binder fibers and a plurality of reinforcing fibers, the bi-component fibers containing a core and a sheath. The core contains a polymer having a melting temperature of at least about 180° C. and the sheath contains a polymer having a melting temperature less than about 180 ° C. A process for forming a molded, cured composite containing forming a structural nonwoven layer and a molded cured nonwoven composite are also disclosed.

First claim

What is claimed is:

1. A process for forming a moldable, uncured nonwoven composite comprising:
forming a structural nonwoven layer having a first side, a second side, and an inner plane located at the mid-plane between the first and second side, wherein the structural nonwoven layer comprises a plurality of bi-component binder fibers and a plurality of reinforcing fibers, wherein the bi-component fibers comprise a core and a sheath, wherein the core comprises a polymer having a melting temperature of at least about 180° C. and the sheath comprises a polymer having a melting temperature less than about 180° C.;
at least partially impregnating the structural nonwoven layer with an uncured, water-based thermosetting resin having a cure temperature of at least about 160° C. forming an uncured, wet nonwoven composite;
at least partially drying the uncured, wet nonwoven composite such that the temperature at the inner plane is less than about 130° C. forming an moldable, uncured composite.

2. The process of claim 1 , wherein the structural nonwoven layer before at least partially impregnating with a water-based thermosetting resin comprises between about 5 and 50% by weight binder fibers.

3. The process of claim 1 , wherein the structural nonwoven layer before at least partially impregnating with a water-based thermosetting resin comprises between about 50 and 95% by weight reinforcing fibers.

4. The process of claim 1 , wherein drying the uncured, wet nonwoven layer comprises using superheated steam.

5. The process of claim 1 , wherein the moldable, uncured nonwoven composite is able to be folded 180 degrees.

6. The process of claim 1 , wherein the moldable uncured composite comprises between about 5 and 25% by weight of the water-based thermosetting resin.

7. The process of claim 1 , wherein the reinforcing fibers comprise a fiber selected from the group consisting of bast fiber, a kenaf fiber, a fiberglass fiber, and mixtures thereof.

8. The moldable, uncured nonwoven composite formed by the process of claim 1 .

9. A process for forming a molded, cured composite comprising:
forming a structural nonwoven layer having a first side, a second side, and an inner plane located at the mid-plane between the first and second side, wherein the structural nonwoven layer comprises a plurality of bi-component binder fibers and a plurality of reinforcing fibers, wherein the bi-component binder fibers and a plurality of reinforcing fibers, wherein the bi-component fibers comprise a core and a sheath, wherein the core comprises a polymer having a melting temperature of at least about 180° C. and the sheath comprises a polymer having a melting temperature less than about 180° C.;
at least partially impregnating the structural nonwoven layer with an uncured, water-based thermosetting resin having a cure temperature of at least about 160° C. forming an uncured, wet nonwoven composite;
at least partially drying the uncured, wet nonwoven composite such that the temperature at the inner plane is less than about 130° C. forming an moldable, uncured composite;
cutting the moldable, uncured nonwoven composite;
applying heat and pressure to the moldable, uncured composite to a temperature of at least about 160° C. at least melting the sheath polymer of the binder fibers, bonding at least a portion of the reinforcing fibers to other reinforcing fibers, at least a portion of the reinforcing fibers to the cores of the bi-component binder fibers and at least a portion of the cores of the bi-component binder fibers to other cores of the bi-component binder together, and at least partially curing the thermosetting resin forming the molded, cured composite.

10. The process of claim 9 , wherein the structural nonwoven layer before at least partially impregnating with a water-based thermosetting resin comprises between about 5 and 50% by weight binder fibers.

11. The process of claim 9 , wherein drying the uncured, wet nonwoven composite comprises using superheated steam.

12. The process of claim 9 , wherein the moldable, uncured composite comprises between about 5 and 25% by weight of the water-based thermosetting resin.

13. The process of claim 9 , wherein the reinforcing fibers comprise a fiber selected from the group consisting of bast fiber, a kenaf fiber, a fiberglass fiber, and mixtures thereof.

14. The process of claim 9 , wherein the molded, cured nonwoven composite has a maximum flexural load of at least 28 N.

Assignees

• Milliken & Co

Inventors

• Vogt Kirkland W
• Bahukudumbi Pradipkumar

Classifications

• B32B17/067

  of fibres or filaments · CPC title

• B32B2307/546

  Flexural strength; Flexion stiffness · CPC title

• B32B2262/0269

  Aromatic polyamide fibres · CPC title

• B29B13/023

  Half-products, e.g. films, plates · CPC title

• B32B13/045

  of foam · CPC title