Alkex® Para-Aramid

Often to referred to as Kevlar®, Alkex® is another para-aramid fiber manufactured by Hyosung Advanced Materials in South Korea.  Alkex® offers the same exceptional strength, flexibility, and durability as Kevlar®.

Alkex® fiber from Rocket-Fibers is supplied in a continuous multifilament configuration and precision wound on a cardboard tube for convenient handling and continued processing.  Full sized factory spools and larger volumes are also available.  Additionally, each order includes product certification, guaranteeing the authenticity of your fiber purchase.  

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Denier (g/9000m)
Length (ft)

About This Item

Alkex® Para-Aramid Fibers Properties

PROPERTY 400 Denier 1000 Denier1420 Denier 1500 Denier3000 Denier
Break Strength 20 lbs 50 lbs68 lbs 75 lbs150 lbs
Diameter 0.233mm (0.0093") 0.369mm (0.0178")0.415mm (0.0163") 0.452mm (0.0178")0.603mm (0.0237")
Elongation  ~3.2% ~3.5%~2.7% ~3.6%~3.9%
Filament Count267665100010002000
Spool Size (lbs)715121515
Filament Count267665100010001000

Alkex® Para-Aramid Physical Properties

Para-Aramid fibers such as Alkex® & Kevlar®,  offer a multitude of properties that make them an excellent choice for various applications. Their exceptional strength-to-weight ratio and high break strength provides high tensile strength and modulus, making them ideal for applications requiring robust and durable materials. Para-aramid fibers are great solution for applications where the fiber will be under constant load or a high cycle count, taking advantage of low elongation and creep properties.

Alkex® Para-Aramid Resistance Guide

Para-aramid fibers, such as Alkex® & Kevlar®, exhibit excellent resistance to high temperatures, maintaining their mechanical properties even at elevated temperatures. This heat resistance makes them suitable for applications in thermal insulation and protective clothing. Additionally, para-aramid fibers demonstrate good chemical resistance, enabling them to withstand exposure to acids, alkalis, and many organic solvents without significant degradation. 

This fiber will degrade with prolonged UV light exposure. These fibers will brown and weaken over time.  Please keep this fiber stored away in a dark room and in the UV protective bag the fiber was shipped in.

This fiber will absorb atmospheric moisture up to 5-7% in weight. This fiber should be stored in a cool, dry room with low humidity. A desiccant bag was included with this fiber to prevent regain during transit and short-term storage at your facility.

Acid: Prolonged exposure to concentrated strong acids will cause degradation
Alkali: Degrades with prolonged exposure to Sodium Hypochlorite
Organic Solvent: Moderate degradation in Carbon Tetrachloride and Ethylene Glycol

Continuous Operating Temperature Range (°C): -40 to 170
Short Term Exposure (°C): 420
Degradation Temperature (°C): 480

Alkex® Para-Aramid Property Guide

The table below represents the nominal mechanical properties of Para-aramid fibers.  Alkex® fibers are sold in standard and high-modulus formats tailored for specific applications. 

AF 1000: Standard Modulus  AF 3000: High Modulus

Property Unit of Measure Standard Modulus High Modulus
Tenacity g/d 23.0 23.6
Tensile Modulus g/d 600875
Specific Gravity ratio
Avg. Elongation % 3.5 2.7
Moisture Regain1 % 4.5 3.5
Melt Point °C
Decomp. Temp °C
Creep2 %
< 0.03
Shrinkage3 %
< 0.02

1 Equilibrium moisture regain @ 55% RH

2 Creep @ 40%-58% ultimate tensile strength

3 Shrinkage in dry air @ 177°C for 30 minutes

Alkex® Para-Aramid Performance Properties

  • High strength: Alkex® fibers exhibit very good tensile strength, making them stronger than steel of the same weight.
  • Durability: These fibers are very high modulus, making them very resistant to impact, puncture, and abrasion.
  • Lightweight: Para-aramid fibers offer very good strength-to-weight ratios, enabling the creation of lightweight products without compromising on durability.
  • Heat resistance: Para-aramids like Alkex® possess very good to excellent resistance to heat, allowing them to maintain their strength and integrity in high-temperature environments.
  • Chemical resistance: These fibers exhibit good to very good resistance to various chemicals, including acids and solvents, making Para-aramid suitable for applications with chemical exposure.  Does not do well high highly concentrated acids or bases.
  • Flame resistance: Para-aramids offer excellent flame resistance, providing flame protection and self extinguishing properties. 
  • Dimensional stability: Alkex® fibers maintain their shape and structural integrity even under prolonged stress, ensuring long-term dimensional stability in applications like composites.
  • Energy absorption: These fibers have the ability to absorb and disperse energy, making them effective in reducing the impact force in applications such as ropes and cables.
  • Design flexibility: Para-aramid fibers like Alkex® can be woven, knitted, braided, or incorporated into infinite composite applications, offering design flexibility for manufacturers to create tailored solutions for specific needs.
  • Low Electrical Conductivity: Para-aramids also have high dielectric strength making them well suited for applications in electrical insulation and protective gear.

Additional Information

Type Performance Manufactured Sizes (Denier) Country of MFG
AF1000 Standard Modulus 200, 400, 1000, 1500, 2250, 3000 South Korea
AF3000 High Modulus 1420, 2840 South Korea

Tube Size (Cardboard)
Wardwell 5/8" x 4"
500 FT, 5000 FT
3.7" x 8.5"
1 Spool

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