Details
Carbon Chopped Strands (also called chopped carbon fiber) are short, discontinuous carbon fiber segments that can range in length from 3 to 50 mm. They are made by cutting continuous carbon fiber tows (bundles of filaments) into precise lengths and are either dry or surface-sized to work with different resin systems.
Unlike continuous fibers, carbon chopped strands provide isotropic reinforcement, which increases strength, stiffness, and conductivity in all directions. Carbon chopped strands are commonly used to strengthen thermoplastics, thermosets, concrete, adhesives, and composites, as well as to reduce weight and enhance material functioning.
What are the key features of carbon fiber chopped strands?
High Strength-to-Weight Ratio: Retains 70–90% of the strength of continuous carbon fibers.
Isotropic Reinforcement: Uniformly distributes strength in all directions.
Good dispersion in matrix materials
Lightweight & low density: Density of 1.75–1.85 g/cm³ (lighter than glass fibers).
Thermal & Electrical Conductivity: Enhances material properties when added to polymers or coatings.
Chemically inert and corrosion-resistant: Immune to corrosion, moisture, and solvents.
Customizable: Available in varied lengths, diameters, and surface treatments.
Surface treatment (sizing) available for resin compatibility
How many types of carbon chopped stands?
By Fiber Type:
oPAN-Based Chopped Carbon Fiber: High tensile strength (3,000–7,000 MPa) for structural applications.
oPitch-Based Chopped Carbon Fiber: Higher thermal conductivity (500–1,000 W/m·K) for heat management. Extremely high modulus; used in thermal & EMI shielding
By Surface Treatment:
oSized Carbon Chopped Strands: Coated with epoxy, polyester, or thermoplastic-compatible sizing. for specific resin compatibility (epoxy, PA, PP, etc.)
oUnsized (Dry) Carbon Chopped Strands: Raw fibers for custom surface treatments. best for friction materials, concrete, and high-temp composites.
What are the benefits of using carbon chopped strands?
Thermal Resistance: Retains integrity at high processing temperatures
Uniform Dispersion: Allows consistent mixing into compounds
Cost-Effective: Cheaper than continuous carbon fiber fabrics.
Ease of Processing: Compatible with injection molding, extrusion, and 3D printing.
Versatility: Enhances mechanical, thermal, and electrical properties of host materials.
Weight Reduction: Replaces metal or glass fibers in lightweight composites.
Design Flexibility: Uniform dispersion in polymers, coatings, and concrete.
Product Parameter：
Property | Typical Value / Range |
Fiber Length | 3 mm, 6 mm, 9 mm, 10mm, 12 mm (customizable) |
Fiber Diameter | 5 – 10 μm (standard: 7 μm) |
Tensile Strength | 3.5 – 4.8 GPa |
Tensile Modulus | 230 – 290 GPa |
Density | 1.76 – 1.85 g/cm³ |
Electrical Conductivity | 10⁴ – 10⁵ S/m |
Thermal Conductivity | ~10–100 W/m·K (depends on type) |
Aspect Ratio | 300 – 1200 (length/diameter) |
Sizings Available | Epoxy, polyester, nylon, PP, PEI, PF, thermoplastics |
Note: Exact values depend on fiber type, length, sizing, and base tow.
What applications are carbon chopped strands used in:
Thermoplastic & Thermoset Composites
Reinforcement for polypropylene (PP), polyamide (PA), PEEK, PEI, epoxy, etc.
Used in injection molding, extrusion, and compound formulations
Construction & Civil Engineering
Added to cement, concrete, mortar, and grouts for crack resistance and strength
Automotive
Used in lightweight composite auto parts, brackets, housings, and under-the-hood components
Electronics & EMI Shielding
Electrically conductive plastics, anti-static enclosures, and thermal management materials
Friction & Wear Components
Brake pads, clutches, carbon composites, gaskets
Printing & Additive Manufacturing
Mixed with resins or filaments to make high-performance, reinforced printables
How to store and handle carbon chopped strands?
Environment: Store in a cool, dry place (15–25°C) with <60% humidity.
Packaging: Keep sealed in moisture-proof bags to prevent sizing degradation.
Handling: Use gloves and masks to avoid skin irritation and inhalation.
Shelf Life: 12–24 months (sized strands) / 6–12 months (unsized strands).
FAQ
Q: What’s the difference between chopped carbon fibers and milled carbon fibers?
A: Chopped fibers are longer (usually 3-50 mm), preserve their original structure, and provide greater reinforcing efficiency. Milled fibers are shorter (0.1-1 mm), more randomly oriented, and commonly used as fillers.
Q: Can I use chopped carbon fiber with thermoplastics?
A: Yes. Sized chopped carbon fibers are available for polyamide (PA), polypropylene (PP), PBT, PC, PEI, PEEK, etc., enabling efficient compounding and molding.
Q: How does chopped carbon fiber affect resin viscosity?
A: It may increase the viscosity depending on the loading percentage and fiber length. Use dispersing agents or pre-compounded masterbatches to improve flowability.
Q: Can chopped carbon fibers be used in concrete?
A: Yes. They are used to improve tensile strength, impact resistance, and crack control in concrete, grouts, and cementitious materials.
Q: Are carbon chopped strands conductive?
A: Yes. They are electrically conductive and commonly used in EMI shielding, ESD-safe materials, and thermally conductive plastics.
Q: Can carbon chopped strands be customized?
A: Yes. Custom fiber lengths, diameters, sizings, and even hybrid chopped fibers (carbon + aramid or glass) can be produced for specific applications.
Q: Can Carbon chopped strands be mixed with other fibers (e.g., glass or aramid)?
A: Yes, hybridizing with glass/aramid would improve impact resistance and reduces cost.
Q: How to ensure uniform dispersion in polymers when using carbon chopped strands?
A: Use high-shear mixing or twin-screw extrusion to prevent clumping.
Q: Do carbon chopped fibers affect mold wear during processing?
A: Yes, abrasive fibers can wear molds; use hardened steel or coatings for longevity.
Q: How to choose between PAN and pitch-based carbon strands?
A: PAN for strength/stiffness; pitch for thermal/electrical conductivity.
