U.S. patent application number 14/298597 was filed with the patent office on 2014-09-25 for method of recycling fiber composite materials.
The applicant listed for this patent is Ramazan Asmatulu. Invention is credited to Ramazan Asmatulu.
Application Number | 20140283348 14/298597 |
Document ID | / |
Family ID | 51568062 |
Filed Date | 2014-09-25 |
United States Patent
Application |
20140283348 |
Kind Code |
A1 |
Asmatulu; Ramazan |
September 25, 2014 |
Method of Recycling Fiber Composite Materials
Abstract
A method for recycling a fiber laminae, the fiber laminae being
impregnated with a partially cured resin, the partially cured resin
being expired, the method comprising steps of jetting a solvent
toward the fiber laminae; extracting the partially cured resin from
the fiber laminae, said extraction being effected by impingements
of the solvent jet against the fiber laminae's impregnated
partially cured resin; and drying the fiber laminae.
Inventors: |
Asmatulu; Ramazan; (Wichita,
KS) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Asmatulu; Ramazan |
Wichita |
KS |
US |
|
|
Family ID: |
51568062 |
Appl. No.: |
14/298597 |
Filed: |
June 6, 2014 |
Current U.S.
Class: |
28/168 ;
28/171 |
Current CPC
Class: |
B29K 2105/0872 20130101;
Y02W 30/622 20150501; B29B 17/02 20130101; B29K 2063/00 20130101;
B29K 2105/06 20130101; Y02W 30/62 20150501; B29B 2017/0293
20130101 |
Class at
Publication: |
28/168 ;
28/171 |
International
Class: |
D06B 9/06 20060101
D06B009/06; D06B 1/02 20060101 D06B001/02; D06B 3/18 20060101
D06B003/18 |
Claims
1. A method for recycling a fiber laminae, the fiber laminae being
impregnated with a partially cured resin, the partially cured resin
being expired, the method comprising steps of: (a) jetting a
solvent toward the fiber laminae; (b) extracting the partially
cured resin from the fiber laminae, said extraction being effected
by impingements of the solvent jet against the fiber laminae's
impregnated partially cured resin; and (c) drying the fiber
laminae.
2. The method for recycling the fiber laminae of claim 1 further
comprising a step of providing a tank and a step of conveying the
fiber laminae into the tank, wherein the jetting the solvent toward
the fiber laminae step is performed within the tank.
3. The method for recycling the fiber laminae of claim 2 comprising
a step of further conveying the fiber laminae out of the tank.
4. The method for recycling the fiber laminae of claim 3 wherein
the extracting the partially cured resin step comprises a step of
recovering the partially cured resin from the tank.
5. The method for recycling the fiber laminae of claim 4 further
comprising a step of mixing the solvent and the partially cured
resin within the tank, said mixing step commencing upon performance
of the step of conveying the fiber laminae into the tank, wherein
the recovering the partially cured resin form the tank comprises
evaporative distillation of the solvent and partially cured resin
mixture.
6. The method for recycling the fiber laminae of claim 5 wherein
the evaporative distillation step comprises condensing the solvent,
and further comprising a step of recovering the solvent, said
solvent recovering step comprising collecting the condensed solvent
within the tank or collecting the condensed solvent within a second
container.
7. The method for recycling the fiber laminae of claim 6 further
comprising a step of preliminarily rolling the fiber laminae, and
wherein the conveying the fiber laminae step comprises a roll
dispensing step.
8. The method for recycling the fiber laminae of claim 7 wherein
the solvent recovering step comprises a step of squeezing portions
of the solvent and partially cured resin mixture out of the fiber
laminae, said squeezing step being performed after performance of
the further conveying the fiber laminae out of the tank step and
prior to performance of the drying step.
9. The method for recycling the fiber laminae of claim 8 further
comprising a re-rolling step, said step being performed after
performance of the drying step.
10. The method for recycling the fiber laminae of claim 1 wherein
the solvent is selected from the group consisting of acetone,
toluene, acetonitrile, dimethyl 1 fonnamide, hexane and
tetrahydrofuran.
11. The method for recycling the fiber laminae of claim 10 wherein
the fiber laminae is selected from the group consisting of woven
fiberglass fibers, unidirectional fiberglass fibers, woven carbon
fibers, unidirectional carbon fibers, woven polyaramid fibers, and
unidirectional polyaramid fibers.
Description
CLAIM OF PRIORITY FROM PREVIOUSLY FILED PROVISIONAL PATENT
APPLICATION
[0001] This non-provisional patent application claims the benefit
of and priority from U.S. provisional patent application No.
61/833,442 filed Jun. 10, 2013. The inventor disclosed in and
applicant of said provisional application is the same person as the
person who is disclosed as the inventor in and applicant of the
instant application. The applicant asserts that method and process
steps disclosed and described in the instant application are
substantially identical to those disclosed in said provisional
application.
FIELD OF THE INVENTION
[0002] This invention relates to fiber composites. More
specifically, it relates to the recycling of composite material
comprising fabric or sheets having fibers that have been
pre-impregnated with an epoxy resin.
BACKGROUND OF THE INVENTION
[0003] Fiber reinforced polymer (also called fiber reinforced
plastic) has become a popular material for the fabrication of
various products due to its strength, durability and relative light
weight. Fiber reinforced polymer (FRP) is a composite material
comprising a polymer material reinforced by glass, carbon, aramid
or other types of fibers. Products constructed from FRP are
fabricated using a variety of manufacturing methods including the
use of fabric comprising fibers that have been pre-impregnated with
a resin. This pre-impregnated fabric, or "pre-preg," is typically
produced in the form of sheets or rolls of woven or uni-directional
fibers bound together by a partially cured resin, which is usually
an epoxy. The resin is only partially cured so that the pre-preg
maintains a solid but flexible shape.
[0004] A pre-preg sheet is usually tacky or sticky, which is a
characteristic of the uncured resin. Pre-preg sheets often have
backing film on both sides of the sheets to facilitate easy
handling and storage of the tacky material. Because a pre-preg
comprises resin that has already undergone some curing, the
material has a limited shelf life and may require cold storage to
prevent complete curing, since complete polymerization is most
commonly achieved by heating the pre-preg. Composite structures
built of pre-preg typically require an oven or autoclave to
complete polymerization. Typically, pre-preg material is sold with
a guarantee shelf life of approximately twelve months when stored
at specified cool temperatures.
[0005] After the pre-preg is considered to be expired, it cannot be
used for any primary structural applications. Expired pre-preg
material is currently disposed after expiration of the pre-preg
resin. The pre-preg expires because the resin begins to oxidize,
but the fibers do not usually lose their mechanical strength.
Pre-preg material may be made from fiberglass, carbon and/or
para-aramid synthetic fibers (e.g. Kevlar.RTM.) with different
fiber orientations (unidirectional or woven). Composite laminates
are assemblies of layers of fibrous pre-preg materials, which can
be joined to provide required engineering properties.
BRIEF SUMMARY OF THE INVENTION
[0006] The present invention is directed to a method and apparatus
for recycling expired pre-preg material by dissolving expired resin
from the material using solvent and recovering solvent, resin and
pre-preg fiber for later use.
[0007] Other and further objects, benefits, and advantages of the
present invention will become known to those skilled in the art
upon review of the Detailed Description which follows.
APPLICANT'S STATEMENT REGARDING DRAWINGS
[0008] The Applicant respectfully asserts that the following
written Specification fully facilitates an understanding of the
method steps of the invention; that as a result of such
facilitation of understanding, no finding should be made under MPEP
608.02, 6.23, 6.2301, or PCT Art. 7(2)(ii); that the subject matter
admits of illustration for such facilitation; and that no drawing
submission requirement should be imposed.
DETAILED DESCRIPTION OF PREFERRED MODES OF PERFORMANCE OF THE
METHOD
[0009] The invention comprises methods and materials that allow
expired pre-preg material to be recycled. In an embodiment of the
invention, the expired pre-preg materials are sprayed with a jet of
solvent at room temperature to remove the resin. Solvents that may
be used to remove various types of resin include acetone, toluene,
acetonitrile, dimethylformamid, hexane and tetrahydrofuran. Using a
method according to the present invention, the orientations of the
fibers remain intact and no damage is caused to the fibers.
Different types of fibers typically used to construct resin
impregnated materials, e.g. fiberglass, carbon, and polyaramid
synthetic fibers, with different fiber orientations, can be
recovered with minimal loss of the fiber strength. This method can
be employed for all known pre-pregs and resin systems. The
recovered fibers may be recycled and reused to manufacture a
pre-preg material with a desired resin system with no or minimal
loss in strength and other desired properties when compared to new
material of the same type. The resin and solvent are collected
after treatment of pre-preg material according to the present
invention. Substantially all of the solvent used in the method or
process is recovered by an evaporation and condensation process and
the collected resin can also be reused. Therefore, this invention
provides a technology that may be characterized as "Green" and
environmentally friendly compared to other existing recycling
techniques.
[0010] In another embodiment of the invention, expired pre-preg
material is loaded into an intake of a solvent tank, typically via
rollers. The pre-preg material is conveyed through the solvent tank
for a specified/pre-determined amount of time as required to remove
a substantial amount of resin from the pre-preg fibers. The fibers
are conveyed from the tank, again, typically via rollers. Excess
solvent is squeezed from the fibers and may return to the solvent
tank or to another container. If required or desired, the fibers
may be conveyed for another pass through the same solvent tank, or
through a subsequent solvent tank, in order to further remove
traces of resin. Solvent tanks may be formed from solvent resistant
materials such as stainless steel, glass, polytetrafluoroethylene
or other operable materials. Typically, the fibers are then washed
with water and dried using pressured air, heat or a combination
thereof. The fibers are then typically roller and stored until
required for shipping or use.
[0011] Fluid remaining in a solvent tank after extraction of resin
from pre-preg material contains a mixture of solvent and resin. A
solvent tank may be provided with an outlet proximate the bottom of
the tank to allow the fluid mixture to flow through the outlet to a
collection container, such as a flask. Either a simple distillation
method and apparatus or a rotary evaporator apparatus and method
may be used to separate the solvent from the resin. With either
method, fluid in a collection container is typically heated at
least to the boiling temperature of the solvent. Solvent vapor is
channeled into a condenser where solvent vapors are condensed to
liquid state and collected for recycling. Following separation of
the solvent through evaporation, the collection container contains
substantially only recovered resin which may also be recycled for
further use.
[0012] While the principles of the method of the invention have
been made clear in the above Detailed Description, those skilled in
the art may make modifications to the method steps including their
identity, character, and sequence of performance without departing
from those principles. Accordingly, it is intended that the
description be interpreted as exemplary and not in the limiting
sense, and that the invention be given a scope commensurate with
the appended claims.
* * * * *