U.S. patent application number 12/144105 was filed with the patent office on 2009-01-01 for nanoparticle-containing thermoplastic composites and methods of preparing same.
This patent application is currently assigned to U.S.A. as represented by the Administrator of the National Aeronautics and Space Administration. Invention is credited to Roberto J. Cano, Mark B. Gruber, Brian J. Jensen, Mark A. Lamontia.
Application Number | 20090004460 12/144105 |
Document ID | / |
Family ID | 40160918 |
Filed Date | 2009-01-01 |
United States Patent
Application |
20090004460 |
Kind Code |
A1 |
Gruber; Mark B. ; et
al. |
January 1, 2009 |
Nanoparticle-Containing Thermoplastic Composites and Methods of
Preparing Same
Abstract
High quality thermoplastic composites and composite laminates
containing nanoparticles and/or nanofibers, and methods of
producing such composites and laminates are disclosed. The
composites comprise a thermoplastic polymer and a plurality of
nanoparticles, and may include a fibrous structural reinforcement.
The composite laminates are formed from a plurality of
nanoparticle-containing composite layers and may be fused to one
another via an automated process.
Inventors: |
Gruber; Mark B.;
(Landenberg, PA) ; Lamontia; Mark A.; (Landenberg,
PA) ; Jensen; Brian J.; (Williamsburg, VA) ;
Cano; Roberto J.; (Yorktown, VA) |
Correspondence
Address: |
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION;LANGLEY RESEARCH CENTER
MAIL STOP 141
HAMPTON
VA
23681-2199
US
|
Assignee: |
U.S.A. as represented by the
Administrator of the National Aeronautics and Space
Administration
Washington
DC
|
Family ID: |
40160918 |
Appl. No.: |
12/144105 |
Filed: |
June 23, 2008 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
60946748 |
Jun 28, 2007 |
|
|
|
Current U.S.
Class: |
428/323 ; 156/60;
524/445; 524/496; 524/592; 524/606 |
Current CPC
Class: |
B32B 2262/14 20130101;
C08K 3/346 20130101; B32B 2262/06 20130101; B32B 2262/08 20130101;
C08G 2650/40 20130101; C08L 65/00 20130101; C08L 71/00 20130101;
B32B 27/20 20130101; B32B 2250/05 20130101; B32B 2605/00 20130101;
Y10T 156/10 20150115; C08K 7/24 20130101; C08K 2201/011 20130101;
B82Y 30/00 20130101; C08J 5/005 20130101; B32B 2262/101 20130101;
C08L 2666/20 20130101; B32B 2262/106 20130101; C08L 71/00 20130101;
C08J 2371/00 20130101; C08K 7/06 20130101; C08L 79/08 20130101;
B32B 27/08 20130101; C08J 2379/08 20130101; Y10T 428/25
20150115 |
Class at
Publication: |
428/323 ;
524/592; 524/606; 524/445; 524/496; 156/60 |
International
Class: |
B32B 5/16 20060101
B32B005/16; C08G 73/10 20060101 C08G073/10; C08K 3/04 20060101
C08K003/04 |
Goverment Interests
ORIGIN OF THE INVENTION
[0001] The invention described herein was made by employees of the
United States Government and may be manufactured and used by or for
the Government for Government purposes without payment of any
royalties thereon or therefore.
Claims
1. A nanoparticle-containing composite comprising a thermoplastic
polymer matrix resin and a plurality of nanoparticles.
2. The nanoparticle-containing composite according to claim 1
wherein said plurality of nanoparticles are substantially uniformly
dispersed in said thermoplastic polymer matrix resin.
3. The nanoparticle-containing composite according to claim 1
wherein said thermoplastic polymer matrix resin comprises a
thermoplastic polymer selected from thermoplastic polyetherketones
and thermoplastic polyimides.
4. The nanoparticle-containing composite according to claim 1
wherein said plurality of nanoparticles is selected from carbon
nanotubes, carbon nanofibers, inorganic nanoparticles, organic
nanoparticles, and clay nanoparticles.
5. The nanoparticle-containing composite according to claim 1
comprising from about 0.1 to about 40 weight percent of said
nanoparticles.
6. The nanoparticle-containing composite according to claim 1
wherein said nanoparticles have a particle size of less than about
999 nm.
7. The nanoparticle-containing composite according to claim 6
wherein said nanoparticles have a particle size of less than about
200 nm.
8. The nanoparticle-containing composite according to claim 1
further comprising a fibrous structural reinforcement.
9. The nanoparticle-containing composite according to claim 8
wherein said fibrous structural reinforcement comprises fibers
selected from continuous fibers, long-discontinuous fibers,
discontinuous fibers, and mixtures thereof.
10. The nanoparticle-containing composite according to claim 9
wherein said fibers are selected carbon fibers, glass fibers,
organic fibers, and mixtures thereof.
11. The nanoparticle-containing composite according to claim 8
comprising from about 20 to about 80 volume percent of said fibrous
structural reinforcement.
12. The nanoparticle-containing composite according to claim 8
wherein said plurality of nanoparticles is selected from carbon
nanotubes, carbon nanofibers, inorganic nanoparticles, organic
nanoparticles, and clay nanoparticles, and said composite comprises
from about 0.1 to about 25 weight percent of said plurality of
nanoparticles.
13. The nanoparticle-containing composite according to claim 9
wherein said continuous fibers comprise one of uniformly disposed,
parallel filaments of continuous fibers and cloth woven from
continuous fibers.
14. A nanoparticle-containing composite laminate comprising a
plurality of fused layers of nanoparticle-containing
composites.
15. The nanoparticle-containing composite laminate according to
claim 14 wherein said nanoparticle-containing composites comprise
thermoplastic polymer matrix resin and a plurality of
nanoparticles.
16. The nanoparticle-containing composite laminate according to
claim 15 wherein said nanoparticle-containing composites further
comprise fibrous structural reinforcements,
17. The nanoparticle-containing composite laminate according to
claim 14 wherein said plurality of fused layers comprises from
about 2 layers to about 400 layers of nanoparticle-containing
composites.
18. A method of producing a nanoparticle-containing composite
laminate comprising combining a thermoplastic polymer matrix resin
with a plurality of nanoparticles to form a plurality of
nanoparticle-containing composites, layering the plurality of
nanoparticle-containing composites, and applying heat and/or
pressure to the layered composites to fuse the composites.
19. The method of producing a nanoparticle-containing composite
laminate according to claim 18 further comprising contacting a
fibrous structural reinforcement with the thermoplastic polymer
matrix resin and the plurality of nanoparticles to form the
plurality of composite layers.
20. The method of producing a nanoparticle-containing composite
laminate according to claim 19 wherein the thermoplastic polymer
matrix resin and plurality of nanoparticles are combined and the
fibrous structural reinforcement is contacted with the combination
of thermoplastic polymer resin and plurality of nanoparticles.
21. The method of producing a nanoparticle-containing composite
laminate according to claim 18 wherein applying heat and/or
pressure to the layered nanoparticle-containing composites
comprises an automated process.
22. The method of producing a nanoparticle-containing composite
laminate according to claim 21 wherein the automated process is
selected from automated heated head tape placement, automated
heated head tow placement, automated heated head fiber placement,
and automated heated head tape laying.
Description
FIELD OF THE INVENTION
[0002] The present disclosure relates to high quality thermoplastic
composites containing nanoparticles and/or nanofibers, and to
methods of producing such composites. The present disclosure also
relates to methods of producing high quality
nanoparticle-containing composite laminates.
BACKGROUND OF THE INVENTION
[0003] Thermoplastic composites are high strength material systems
which are finding wide spread application in a variety of fields
including aero structures, non-aero military structures, such as
tanks and armored vehicles, and non-military structures such as
automotive components, sporting goods, and industrial and medical
devices. Typically, the composites comprise fiber reinforcements
embedded in a resin matrix. Fiber reinforcements which have been
contacted, e.g., coated and/or impregnated, with a resin are
layered and joined to one another to form a composite laminate.
Recently, automated lay-up of fiber-reinforced resin composites has
replaced hand lay-up as a more economical and efficient method of
producing composite laminates. Automated composite lay-up, such as
heated head tape placement, filament winding, etc. requires the
fiber-reinforced composites to have certain processing
characteristics to produce high quality laminates. Additionally,
there is an ongoing desire to improve the functional and mechanical
properties of the laminates and to tailor these properties to
specific applications.
SUMMARY OF THE INVENTION
[0004] In accordance with an embodiment, a nanoparticle-containing
composite comprises a thermoplastic polymer matrix resin and a
plurality of nanoparticles. In some embodiments, the composite may
also include a fibrous structural reinforcement.
[0005] In accordance with another embodiment, a
nanoparticle-containing composite laminate comprises a plurality of
fused layers of nanoparticle-containing composites.
[0006] In accordance with yet another embodiment, a method of
producing a nanoparticle-containing composite laminate comprises
combining a thermoplastic polymer matrix resin with a plurality of
nanoparticles to form a plurality of nanoparticle-containing
composites, layering the plurality of nanoparticle-containing
composites, and applying heat and/or pressure to the layered
composites to fuse the composites. In some embodiments, the method
may also include contacting a fibrous structural reinforcement with
the thermoplastic polymer matrix resin and plurality of
nanoparticles to form the plurality of nanoparticle-containing
composites. Advantageously, in some embodiments the application of
heat and/or pressure may be via an automated process.
[0007] Nanoparticle-containing thermoplastic composites and
composite laminates, and methods of producing
nanoparticle-containing thermoplastic composites and composite
laminates provide numerous advantages in the art. For example,
thermoplastic composites that are suitable for automated placement
e.g., non-autoclave fabrication, provide an economical method to
prepare high quality composite laminates cost effectively.
Additionally, the size constraints imposed by autoclave fabrication
may be eliminated allowing the nanoparticle-containing
thermoplastic composite laminates to be utilized in a multitude of
new applications.
[0008] Nanoparticle-containing thermoplastic composites and
composite laminates may possess a variety of improved mechanical
and functional properties. For example, thermoplastic composites
having improved strength, modulus, impact resistance, toughness,
conductivity, permeation resistance, and radiation absorption may
be prepared according to the present embodiments. The disclosed
nanoparticle-containing thermoplastic composites may have improved
thermal and flame resistance, improved moisture and chemical
resistance, increased hydrophobicity or oleophobicity, increased
hydrophilicity or oleophilicity, and improved charge dissipation,
and thermal/electrical conductivity. Additionally, the
nanoparticle-containing thermoplastic composites may have unique
and advantageous crystalline and/or amorphous properties. As an
additional advantage, the presently disclosed
nanoparticle-containing composite laminates may be particularly
well-suited for automated processing. Automated processing, such as
heated head placement and filament winding offer a low cost
alternative to autoclave and press fabrication, and produce
composites having properties that cannot be achieved using other
processing methods. For example, automated tape laying processing
provides extremely fast heat-up and cool down rates, and may allow
unique crystalline and/or amorphous composite laminates to be
formed.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0009] Nanoparticle-containing composites, according to an
embodiment, may comprise a thermoplastic polymer matrix resin and a
plurality of nanoparticles. In some embodiments, the composites may
further include a fibrous structural reinforcement.
[0010] The thermoplastic polymer matrix resin may comprise any of a
multitude of thermoplastic polymers including those commonly used
in the composites art. For example, thermoplastic polymers may
include, but are not limited to: thermoplastic polyketones,
including polyetherketones, such as PEEK and PEKK; polyethylene;
polypropylene; polyimides, such as the ULTEM family of products
available from G.E. Plastics, and the family of products available
from IMITEC based on a license from NASA Langley Research Center;
polyarylene ethers; polysulfones; polyamides, such as nylon;
polyesters; polystyrene; acrylonitrile butadiene styrene (ABS);
acrylic; celluloid; cellulose acetate; ethylene vinyl acetate
(EVA); ethylene vinyl alcohol (EVAL); fluoroplastics, such as PTFE,
FEP, PFA, CTFE, ECTFE, and ETFE; ionomers; liquid crystal polymers
(LCP); polyacetal (POM or acrylonitrile); polyamide-imide (PAI);
polyaryletherketone (PAEK); polybutadiene (PBD); polybutylenes;
polybutylene terephthalate (PBT); polyethylene terephthalate (PET);
polycyclohexylene dimethylene terephthalate (PCT); polycarbonate,
polyhydroxyalkanoates (PHAs); polyester polyetherimide (PEI);
polysulfones, including polyethersulfone; polyethylenechlorinates;
polylactic acid; polymethylpentene; polyphenylene oxide;
polyphenylene sulfide; polyphthalamide; polyvinyl chloride;
polyvinylidene chloride; and mixtures thereof may be utilized in
embodiments. Additional thermoplastic polymers which may be used
include those which are suitable for carrying mechanical loads,
resisting degradation at elevated temperatures, and/or resisting
dissolution in solvents. The particular selection of a
thermoplastic polymer depends on the desired end use for the
composite, and is well within the ordinary skill of those in the
art.
[0011] Thermoplastics are designed to melt, flow, and consolidate
and are typically non-reactive. Thus, thermoplastics generally do
not undergo a chemical reaction during processing and do not
require additives such as curing agents, accelerators and
hardeners. However, in some embodiments, one or more additives may
be utilized to tailor the properties of the thermoplastic to the
processing parameters. For example, in some embodiments, a flow
modifier may be added to the thermoplastic polymer to adjust the
melt viscosity of the polymer. The particular selection of a flow
modifier may depend on the thermoplastic polymer being used and the
method of processing, and is well within the ordinary skill of
those in the art.
[0012] According to the present disclosure, the composite also
includes a plurality of nanoparticles. The nanoparticles may be
formed from any of a variety of materials. In many embodiments, the
nanoparticles resist being melted, compressed or flattened when
exposed to the pressures and temperatures encountered during
processing, e.g., the nanoparticles remain rigid. Some exemplary
materials from which the nanoparticles may be formed include, but
are not limited to, inorganic materials, such as ceramics,
silicons, and clays, and organic materials, such as carbon,
including carbon nanotubes and carbon nanofibers. The particular
selection of material may depend on the desired end use for the
composite and the property enhancement desired. For example, in
some embodiments, nanoparticles comprising carbon nanotubes may
improve mechanical properties of a composite, such as strength,
modulus, and toughness, and functional properties including
conductivity and static discharge. A variety of nanoparticles are
commercially available and the particular selection of
nanoparticles for a particular application is well within the
ordinary skill of those in the art.
[0013] The nanoparticles, according to embodiments, may have a
multitude of configurations, including but not limited to:
bead-like spheres, oblate spheroids, tubes, fibers, and/or one or
more irregular shapes. The nanoparticles may have any size that
does not adversely affect the melt flow of the thermoplastic
polymer matrix resin. For example, the nanoparticles may have a
particle size of less than about 999 nm, or less than about 700 nm,
or less than about 500 nm, or as a further example, a particle size
of less than about 200 nm.
[0014] The composites may include varying amounts of nanoparticles.
For example, in some embodiments the nanoparticles may comprise
from about 0.1 to about 40 wt % of the total composite, or from
about 0.1 to about 25 wt %, or from about 0.1 to about 10 wt %, or
as yet another example, from about 0.5 to about 5 wt % of the total
composite. The particular amount may depend on a variety of
factors, including for example, the property enhancement desired
for the composite. For example, in some embodiments, one or more
functional properties of a fiber reinforced composite may be
improved by including carbon nanotubes in an amount ranging from
about 0.1 to about 3 wt % of the total composite, while structural
properties, such as tensile strength, may be improved by including
carbon nanotubes in an amount ranging from about 3 to about 15 wt %
of the total composite, and permeation in a composite may be
reduced by including clay nanoparticles in an amount ranging from
about 3 to about 15 wt % of the total composite. Another factor
which may be considered in determining the amount of nanoparticles
in the composite is whether the composite includes a fibrous
structural reinforcement. For example, in some embodiments which do
not include a fibrous structural reinforcement, the amount of
nanoparticles may be greater than the amount in composites which do
include a fibrous structural reinforcement.
[0015] In some embodiments, the nanoparticle-containing composite
may include a fibrous structural reinforcement. A fibrous
structural reinforcement may comprise fibers of varying lengths,
including: continuous fibers, e.g., fibers having a length of
greater than about 4 inches; long-discontinuous fibers, e.g.,
fibers having a length of from about 0.5 to about 4 inches; and
discontinuous fibers, e.g., fibers having a length of less than
about 0.5 inches. Continuous fiber structural reinforcements may
have a variety of configurations including, for example, tapes or
tows comprising uniformly disposed, parallel filaments and/or cloth
woven from continuous fiber tow. Long-discontinuous fiber
reinforcements may also have a variety of configurations including,
for example, uniformly disposed, parallel filaments or cloth woven
from long-discontinuous fiber tow. Similarly, a variety of
discontinuous fiber structural reinforcements may be utilized,
including, for example, random mats of discontinuous fibers.
[0016] Fibrous structural reinforcements, e.g., those comprising
continuous fibers, long-discontinuous fibers, and/or discontinuous
fibers, may comprise any of numerous kinds of fibers including
synthetic and/or natural fibers. For example, in some embodiments,
fibrous structural reinforcements may comprise one or more of:
glass fibers and/or fibers formed of silicon carbide; alumina;
titania; boron and the like; carbon and/or graphite fibers; as well
as fibers formed from organic polymers, such as aromatic
polyamides, polyethylenes, polyolefins, polyarylates, and polyaryl
ethers. In an exemplary embodiment, the continuous fibrous
structural reinforcement may comprise glass fibers, carbon fibers
and/or aramid fibers such as the fibers sold by the DuPont Company
under the tradename KEVLAR.RTM. or fibers sold by Tiejin under the
tradename TWARON.RTM..
[0017] The fibrous structural reinforcement, when present, may
comprise varying proportions of the final composite. The proportion
may be dependent on the end use envisioned, as well as the
particular resin, fiber and processing method utilized. In some
embodiments, the fibrous structural reinforcement may comprise from
about 20 vol % or less to about 80 vol % or more of the total
composite. For example, the fibrous structural reinforcement, when
present, may comprise about 20, 25, 30, 35, 40, 45, 50, 55, 60, 65,
70, 75 or 80 vol % of the final composite, including any and all
values and ranges therebetween.
[0018] Nanoparticle-containing composites may be produced, in some
embodiments, by combining a plurality of nanoparticles with a
thermoplastic polymer matrix resin. The plurality of nanoparticles
may be combined with the thermoplastic polymer in a variety of
ways, and preferably the method of combining achieves a
substantially uniform dispersion of nanoparticles in the polymer.
For example, the method of combining preferably results in the
nanoparticles forming a substantially homogenous dispersion
throughout the thickness of the polymer. In many embodiments, the
nanoparticles may be combined with a thermoplastic polymer in a
liquid state, such as a molten liquid state. Alternatively, the
nanoparticles may be combined with a thermoplastic polymer matrix
resin solution. In other embodiments, the nanoparticles may be
combined with a thermoplastic polymer in a solid state, for
example, the particles may be combined with a thermoplastic polymer
in a powder form. In some embodiments, the nanoparticles may be
sprayed or dispersed on the surface of the thermoplastic polymer.
However, these embodiments do not typically achieve a substantially
uniform dispersion of nanoparticles through the thickness of the
polymer, but may be used in applications wherein a surface coating
of particles achieves a desired property enhancement.
[0019] In some embodiments, the method of producing a
nanoparticle-containing composite may also include contacting,
e.g., impregnating, a fibrous structural reinforcement with the
thermoplastic polymer matrix resin and the plurality of
nanoparticles. In many embodiments, the thermoplastic polymer
matrix resin and plurality of nanoparticles may be combined prior
to contacting the fibrous structural reinforcement. However, in
some embodiments, the fibrous structural reinforcement may be
contacted with the thermoplastic polymer matrix resin and
nanoparticles separately, e.g., prior to their being combined. For
example, the fibrous structural reinforcement may be first
contacted with the polymer matrix resin and subsequently contacted
with the nanoparticles or alternatively, the fibrous structural
reinforcement may be contacted with the nanoparticles and
subsequently contacted with the polymer matrix resin.
[0020] The fibrous structural reinforcement may be impregnated with
the thermoplastic polymer matrix resin or the combination of
thermoplastic polymer matrix resin and nanoparticles using any of
numerous methods ordinarily used for impregnating fiber
reinforcements. For example, exemplary methods may include melt
coating, calendaring, dip impregnation with a resin solution or
molten resin, melt pressing the tape or fabric in a film of the
nanoparticle-containing thermoplastic polymer or the like. A
variety of factors may affect the choice of which method to utilize
including, for example, the solubility of the thermoplastic polymer
in a particular solvent and/or the viscosity of the polymer, and
the particular selection is well within the ordinary skill of those
in the field.
[0021] The nanoparticle-containing composites, according to the
present disclosure, may be used to form multi-ply composite
laminates. For example, a multi-ply composite laminate may comprise
a plurality of nanoparticle-containing composites layered over one
another. For example, a multi-ply composite laminate may include as
few as two layers or as many as several hundreds of layers, e.g.,
about 200, 300, 400 or even more layers, depending on the desired
end use. Individual layers may be from about 1 mil to about 20 mils
thick. For example, layers formed using unidirectional tapes may be
about 5 mils thick, while layers formed from woven fabrics may have
a thickness greater than about 5 mils.
[0022] In many embodiments, the multi-ply composite laminate may
comprise a plurality of layers of nanoparticle-containing
composites that have been joined or fused to one another. For
example, the layers may be fused to one another by the application
of heat and/or pressure using any of the variety of methods and
conventional processing devices and equipment ordinarily used for
the production of layered composites. Advantageously, in many
embodiments, the composite laminates may be formed using an
automated process. However, in other embodiments, non-automated
processes may be utilized. Some exemplary processing methods may
include, but are not limited to: automated heated head tape
placement; automated heated head tow placement; automated heated
head fiber placement; automated heated head tape laying; automated
fast tacking with automated heated head tape, tow, or fiber
placement; automated fast tacking with autoclave post curing;
automated fast tacking with automated tape laying or autoclave post
curing; filament winding; roll forming; stretch forming;
superforming; matched die forming; hydroforming; wet laying; panel
thermoforming; in-line thermoforming; diaphragm forming; extrusion;
pultrusion, sheet extrusion; injection molding; compression
molding; resin transfer molding (RTM); rotation molding; blow
molding; film casting; tow impregnation and consolidation; tape
impregnation and consolidation; calendaring; foam processing;
thermoplastic adhesive bonding; thermoplastic induction welding;
thermoplastic resistance welding; thermoplastic focused infrared
welding; thermoplastic ultrasonic welding; thermoplastic hot plate
welding; thermoplastic vibration welding; thermoplastic laser
welding; and/or thermoplastic microwave welding.
[0023] The use of the terms "a" and "an" and "the" and similar
referents in the context of describing the invention (especially in
the context of the following claims) are to be construed to cover
both the singular and the plural, unless otherwise indicated herein
or clearly contradicted by context. The terms "comprising",
"having", "including", and "containing" are to be construed as
open-ended terms (i.e., meaning "including, but not limited to,")
unless otherwise noted. The use of any and all exemplary language
(e.g., "such as") provided herein, is intended merely to better
illuminate the invention and does not pose a limitation on the
scope of the invention unless otherwise claimed. No language in the
specification should be construed as indicating any non-element
claimed element as essential to the practice of the invention.
[0024] Preferred embodiments of this invention are described
herein, including the best mode known to the inventors for carrying
out the invention. Variations of those preferred embodiments may
become apparent to those of ordinary skill in the art upon reading
the foregoing description. The inventors expect skilled artisans to
employ such variations as appropriate, and the inventors intend for
the invention to be practiced otherwise than as specifically
described herein. Accordingly, the invention includes all
modifications and equivalents of the subject matter recited in the
claims appended hereto as permitted by applicable law. Moreover,
any combination of the above-described elements in all possible
variations thereof is encompassed by the invention unless otherwise
indicated herein or otherwise clearly contradicted by context.
* * * * *