Processes for recycling carpet and products of such processes

Patent metadata

Field	Value
Publication number	US-9757875-B2
Application number	US-201414485175-A
Country	US
Kind code	B2
Filing date	Sep 12, 2014
Priority date	Nov 4, 2011
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

Methods for the recycling of carpet are disclosed that produce clean face fiber suitable for industrial use. The methods allow the recovery of face fiber material, for example a polyester or a polyamide, from carpets that includes a face fiber material and a backing material, and include the steps of heating the carpet to a temperature lower than the melting point of the face fiber material, but higher than the initial thermal decomposition temperature of the backing material, for a time and at a temperature sufficient to thermally decompose, pyrolyze, or oxidize at least a portion of the backing material, rendering the backing material friable, that is more friable than the untreated backing; and applying mechanical force to the carpet so as to liberate the friable backing material from the face fiber material.

First claim

We claim:

1. A method of separating entangled carpet fibers, the method comprising:
a) providing a carpet comprising two or more different fibers that are entangled, wherein the second fiber has a lower thermal decomposition temperature than the first fiber;
b) heating the entangled fibers to a temperature lower than the melting point of the first fiber, but higher than the thermal decomposition temperature of the second fiber, for a time and at a temperature sufficient to thermally decompose at least a portion of the second fiber, rendering the second fiber friable; and
c) applying mechanical force to the entangled fibers so as to liberate the first fiber from the friable second fiber.

Assignees

• Shaw Ind Group Inc

Inventors

• Bork Joseph E
• Paspek Sr Stephen C
• Schroeder Alan F
• Heise William H

Classifications

• C08J2377/06

  Polyamides derived from polyamines and polycarboxylic acids (C08J2377/10 takes precedence) · CPC title

• D01B9/00

  Other mechanical treatment of natural fibrous or filamentary material to obtain fibres or filaments · CPC title

• B29B17/02 Primary

  Separating plastics from other materials · CPC title

• B29K2077/00

  Use of {PA, i.e.} polyamides, e.g. polyesteramides {or derivatives thereof}, as moulding material · CPC title

• B29K2105/06

  containing reinforcements, fillers or inserts · CPC title