| Your premier source for prepreg carbon fiber and graphite braid. |
How soon can I get the materials I ordered?
Most orders received by 3pm EST will be shipped out the same day, and can be shipped overnight upon request. Orders of prepreg
other than precut 6' sheets or whole rolls may require additional time to safely bring up to temperature for cutting & rolling. Prepregs
and resin sheets must be sent overnight.
What's the difference between Acrylic Wet Lamination & Prepreg?
Carbon Express uses both techniques. There are two ways to create a fiber reinforced laminate; "wet" layup and pre-impregnated
fiber layup. The "wet" laminate process has been used since the introduction of composites to create molded shapes from glass or
carbon fiber and resin. It is the easiest and least labor intensive method available for molding composites parts and is utilized
primarily to create product without large capital investment. It gives a really nice finish, and any color pigment or fabric print can be
added. Layups are easy, strong, and if done correctly, light weight.
The pre-impregnated (pre-preg) fiber method has been developed over the past 50 years to create stiffer, stronger laminates with
controlled, predictable results. The fiber is preimpregnated with resin and frozen to prevent the resin from curing prematurely. This
material is thawed and hand laid into a mold to the proper thickness and cured. The resulting laminate has a precisely controlled
resin volume and will be stiffer and stronger than a wet laminate of equivalent thickness. Initially developed for the aerospace
industry, prepregs are now used in a wide range of applications - from golf clubs to satellite arrays, and from wind turbine rotor
blades.
Prepregs are supplied to customers in roll form, to be stored frozen and defrosted before use. When cured at elevated
temperatures and under pressure, prepregs form molded components that are extremely strong and stiff. A broad range of
formulated resins are used to impregnate the woven and unidirectional reinforcements. Epoxy resins provide the highest levels of
toughness and good environmental resistance.
How is this material cured?
Depending upon the type of prepreg being cured, typical temperatures are between are 200oF and 300oF for one to three hours.
Prepreg also needs pressure to facilitate the commingling of materials. Standard types of pressure include vacuum bagging or
autoclave.
How are prepregs and adhesive film stored and handled?
Prepreg & adhesive films can be stored at room temperature for about 7 days, and up to 30 days in the refrigerator, or, it can be
kept frozen at 0oF for up to one year.
The prepregs and resins Carbon Express carries are b-staged epoxy resins (partially advanced thermosetting resins) which can
react with water and be detrimental to the final part performance. Moisture present in the epoxy resin during cure can result in voids,
depressed Tg and reduced mechanical performance.
Freezer (0°F) or Refrigerator (40°F) Storage:
For optimum performance and processability, prepreg should be stored and sealed in
plastic to prevent moisture absorption during storage as well as when the product is
brought out to stabilize to room temperature. Since condensation may form during
this stabilization period, the sealed plastic barrier prevents the condensation from
being absorbed by the prepreg. Do not remove the plastic from the prepreg until the
material has equilibrated to room temperature and no condensation is present.
Room Temperature storage:
Prepreg should be stored at room temperature (75°F) or lower. While refrigerated storage is best to retain product shelf life and out
time, prepregs should be stored at less than 55% humidity and used quickly when exposed to room temperature. Temperatures
above 75°F will shorten the useful working life of prepreg products.
Detrimental Effects of Moisture:
Moisture causes voids due to water vapor expansion during the molding cycle. Moisture absorbance can result in increasing resin
flow that affects the final retained resin content of the molded part, which may impact physical and mechanical performance and
properties of the final part. The use of a vacuum bag during the curing of prepreg(s) will not necessarily remove moisture at a rate
comparable to the removal of air.
Are prepregs hazardous? How are they shipped?
Carbon fiber and graphite braid are inert material. All of Carbon Express’s materials can be shipped overnight. Prepregs and epoxy
adhesive films are not considered hazardous, and are safe when used according to manufacturer specifications. Prepregs do
contain epoxy resins and amines, which may cause skin irritation. Nitrile gloves are recommended. If skin contact occurs, wash with
soap and water as soon as possible. If eye contact occurs, rinse with water for 15 minutes.
How or where can I learn more about the use of and handling of prepreg?
Part of our mission is to help you understand the practical application of using our materials. Michael B. Smith has been working with
these materials for several years, and will coach your team how to make orthotics and prosthetics from prepreg. Our commitment to
customer service includes supporting you through technical and practical use of prepreg techniques in your office, and
troubleshooting common reasons for product failure.
How are carbon fibers and graphite produced?
Carbon fiber is a long, thin strand of material with a diameter of 6-10um or about five times thinner than an average human hair, and
composed mostly of carbon atoms. The carbon atoms are bonded together in microscopic crystals that are aligned parallel to the
long axis of the fiber. The crystal alignment makes the fiber incredibly strong for its size. Several thousand carbon fibers are twisted
together to form a yarn, which may be used by itself or woven into a fabric. Yarn or fabric is combined with epoxy and molded into
shape to form various composite materials.
Carbon fibers are made from organic polymers such as poly(acrylonitrile). To make carbon fibers, the polymer is stretched into
alignment parallel with the axis of the fiber. Then, an oxidation treatment in air between 200- 300oC transforms the polymer into a
nonmeltable precursor fiber. This precursor fiber is then heated in a nitrogen environment. As the temperature is raised, volatile
products are given off until the carbon fiber is composed of at least 92% carbon. The temperature used to treat the fibers varies
between 1000oC and 2500oC depending on the desired properties of the carbon fiber. When carbon fibers are used in industry,
they are woven into sheets, tubes, or other desired shapes. Epoxy resins or other binders are often added to the carbon fibers. The
resulting composite of epoxy and carbon fibers is stronger than either component individually.
If during the treatment process the temperature is raised over 2500oC, graphite will form instead of carbon fibers. Most of the
graphite used in industry is manufactured by heating petroleum byproducts to about 2800oC. The petroleum byproducts are similar
to the polymers used in the carbon fiber process. Both graphite and carbon fibers are rigid materials resistant to stretching and
compression. They are chemically inert, or unreactive. This is critical because it means that carbon fibers don't react with the outer
part of a tennis racket, and graphite pencil leads don't react with paper. The inertness of carbon fibers makes them suitable for
medical applications.
Carbon fibers are classified by the tensile modulus of the fiber. Tensile modulus is a measure of how much pulling force a certain
diameter fiber can exert without breaking. The English unit of measurement is pounds of force per square inch of cross-sectional
area, or psi. Carbon fibers classified as "low modulus" have a tensile modulus below 34.8 million psi (240 million kPa). Other
classifications, in ascending order of tensile modulus, include "standard modulus," "intermediate modulus," "high modulus," and
"ultrahigh modulus." Ultrahigh modulus carbon fibers have a tensile modulus of 72.5 -145.0 million psi (500 million-1.0 billion kPa). As
a comparison, steel has a tensile modulus of about 29 million psi (200 million kPa). Thus, the strongest carbon fibers are ten times
stronger than steel and eight times that of aluminum, not to mention much lighter than both materials, 5 and 1.5 times, respectively.
Additionally, their fatigue properties are superior to all known metallic structures, and they are one of the most corrosion-resistant
materials available, when coupled with the proper resins.
Does Carbon Express have employment opportunities?
Yes, we are looking for orthotists and prosthetists to join our team, as well as technical assistance. We are willing to train the right
individual.
Most orders received by 3pm EST will be shipped out the same day, and can be shipped overnight upon request. Orders of prepreg
other than precut 6' sheets or whole rolls may require additional time to safely bring up to temperature for cutting & rolling. Prepregs
and resin sheets must be sent overnight.
What's the difference between Acrylic Wet Lamination & Prepreg?
Carbon Express uses both techniques. There are two ways to create a fiber reinforced laminate; "wet" layup and pre-impregnated
fiber layup. The "wet" laminate process has been used since the introduction of composites to create molded shapes from glass or
carbon fiber and resin. It is the easiest and least labor intensive method available for molding composites parts and is utilized
primarily to create product without large capital investment. It gives a really nice finish, and any color pigment or fabric print can be
added. Layups are easy, strong, and if done correctly, light weight.
The pre-impregnated (pre-preg) fiber method has been developed over the past 50 years to create stiffer, stronger laminates with
controlled, predictable results. The fiber is preimpregnated with resin and frozen to prevent the resin from curing prematurely. This
material is thawed and hand laid into a mold to the proper thickness and cured. The resulting laminate has a precisely controlled
resin volume and will be stiffer and stronger than a wet laminate of equivalent thickness. Initially developed for the aerospace
industry, prepregs are now used in a wide range of applications - from golf clubs to satellite arrays, and from wind turbine rotor
blades.
Prepregs are supplied to customers in roll form, to be stored frozen and defrosted before use. When cured at elevated
temperatures and under pressure, prepregs form molded components that are extremely strong and stiff. A broad range of
formulated resins are used to impregnate the woven and unidirectional reinforcements. Epoxy resins provide the highest levels of
toughness and good environmental resistance.
How is this material cured?
Depending upon the type of prepreg being cured, typical temperatures are between are 200oF and 300oF for one to three hours.
Prepreg also needs pressure to facilitate the commingling of materials. Standard types of pressure include vacuum bagging or
autoclave.
How are prepregs and adhesive film stored and handled?
Prepreg & adhesive films can be stored at room temperature for about 7 days, and up to 30 days in the refrigerator, or, it can be
kept frozen at 0oF for up to one year.
The prepregs and resins Carbon Express carries are b-staged epoxy resins (partially advanced thermosetting resins) which can
react with water and be detrimental to the final part performance. Moisture present in the epoxy resin during cure can result in voids,
depressed Tg and reduced mechanical performance.
Freezer (0°F) or Refrigerator (40°F) Storage:
For optimum performance and processability, prepreg should be stored and sealed in
plastic to prevent moisture absorption during storage as well as when the product is
brought out to stabilize to room temperature. Since condensation may form during
this stabilization period, the sealed plastic barrier prevents the condensation from
being absorbed by the prepreg. Do not remove the plastic from the prepreg until the
material has equilibrated to room temperature and no condensation is present.
Room Temperature storage:
Prepreg should be stored at room temperature (75°F) or lower. While refrigerated storage is best to retain product shelf life and out
time, prepregs should be stored at less than 55% humidity and used quickly when exposed to room temperature. Temperatures
above 75°F will shorten the useful working life of prepreg products.
Detrimental Effects of Moisture:
Moisture causes voids due to water vapor expansion during the molding cycle. Moisture absorbance can result in increasing resin
flow that affects the final retained resin content of the molded part, which may impact physical and mechanical performance and
properties of the final part. The use of a vacuum bag during the curing of prepreg(s) will not necessarily remove moisture at a rate
comparable to the removal of air.
Are prepregs hazardous? How are they shipped?
Carbon fiber and graphite braid are inert material. All of Carbon Express’s materials can be shipped overnight. Prepregs and epoxy
adhesive films are not considered hazardous, and are safe when used according to manufacturer specifications. Prepregs do
contain epoxy resins and amines, which may cause skin irritation. Nitrile gloves are recommended. If skin contact occurs, wash with
soap and water as soon as possible. If eye contact occurs, rinse with water for 15 minutes.
How or where can I learn more about the use of and handling of prepreg?
Part of our mission is to help you understand the practical application of using our materials. Michael B. Smith has been working with
these materials for several years, and will coach your team how to make orthotics and prosthetics from prepreg. Our commitment to
customer service includes supporting you through technical and practical use of prepreg techniques in your office, and
troubleshooting common reasons for product failure.
How are carbon fibers and graphite produced?
Carbon fiber is a long, thin strand of material with a diameter of 6-10um or about five times thinner than an average human hair, and
composed mostly of carbon atoms. The carbon atoms are bonded together in microscopic crystals that are aligned parallel to the
long axis of the fiber. The crystal alignment makes the fiber incredibly strong for its size. Several thousand carbon fibers are twisted
together to form a yarn, which may be used by itself or woven into a fabric. Yarn or fabric is combined with epoxy and molded into
shape to form various composite materials.
Carbon fibers are made from organic polymers such as poly(acrylonitrile). To make carbon fibers, the polymer is stretched into
alignment parallel with the axis of the fiber. Then, an oxidation treatment in air between 200- 300oC transforms the polymer into a
nonmeltable precursor fiber. This precursor fiber is then heated in a nitrogen environment. As the temperature is raised, volatile
products are given off until the carbon fiber is composed of at least 92% carbon. The temperature used to treat the fibers varies
between 1000oC and 2500oC depending on the desired properties of the carbon fiber. When carbon fibers are used in industry,
they are woven into sheets, tubes, or other desired shapes. Epoxy resins or other binders are often added to the carbon fibers. The
resulting composite of epoxy and carbon fibers is stronger than either component individually.
If during the treatment process the temperature is raised over 2500oC, graphite will form instead of carbon fibers. Most of the
graphite used in industry is manufactured by heating petroleum byproducts to about 2800oC. The petroleum byproducts are similar
to the polymers used in the carbon fiber process. Both graphite and carbon fibers are rigid materials resistant to stretching and
compression. They are chemically inert, or unreactive. This is critical because it means that carbon fibers don't react with the outer
part of a tennis racket, and graphite pencil leads don't react with paper. The inertness of carbon fibers makes them suitable for
medical applications.
Carbon fibers are classified by the tensile modulus of the fiber. Tensile modulus is a measure of how much pulling force a certain
diameter fiber can exert without breaking. The English unit of measurement is pounds of force per square inch of cross-sectional
area, or psi. Carbon fibers classified as "low modulus" have a tensile modulus below 34.8 million psi (240 million kPa). Other
classifications, in ascending order of tensile modulus, include "standard modulus," "intermediate modulus," "high modulus," and
"ultrahigh modulus." Ultrahigh modulus carbon fibers have a tensile modulus of 72.5 -145.0 million psi (500 million-1.0 billion kPa). As
a comparison, steel has a tensile modulus of about 29 million psi (200 million kPa). Thus, the strongest carbon fibers are ten times
stronger than steel and eight times that of aluminum, not to mention much lighter than both materials, 5 and 1.5 times, respectively.
Additionally, their fatigue properties are superior to all known metallic structures, and they are one of the most corrosion-resistant
materials available, when coupled with the proper resins.
Does Carbon Express have employment opportunities?
Yes, we are looking for orthotists and prosthetists to join our team, as well as technical assistance. We are willing to train the right
individual.
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |