Twaron® high performance yarn
Twaron® para-aramid yarn is suitable for use across a wide range of challenging applications and industries, from ballistic protection to heat and cut protection, and from oil and gas to the automotive and telecommunications industries. The unique characteristics of Twaron® are the result of a 100% Para crystalline structure with molecular chains preferentially oriented along the yarn filament axis.
Twaron® combines the following characteristics, which distinguishes it from other synthetic yarns:
- High strength: excellent strength-to-weight ratio
- High modulus
- High dimensional stability: very low creep, small negative thermal expansion coefficient
- Excellent thermal stability: usable across a wide temperature range, no melting point, high heat stability, low heat conductivity
- High cut resistance
- Good chemical resistance
- Low flammability
- Electrically non-conductive
- Long, well-defined lifetime
How is Twaron® produced?
Dedicated specialists in the manufacturing departments continually monitor the production of Twaron®, which is made from monomers in three stages: polymerization, continuous filament yarn spinning and converting.
During the first stage, the monomers are combined into a firm, fine-grained para-aramid polymer. This material has the typical heat resistance and chemical properties of para-aramid. The fine-grained powder can be used to improve the properties of plastic components. However, the powder does not yet possess the distinctive mechanical properties of yarn or pulp.
Continuous filament yarn spinning
The second stage involves dissolving the polymer in sulfuric acid, which produces a liquid crystalline solution. This solution is then spun into fine, natural yellow or dope-dyed black continuous filament yarns, with each filament being as low as 12 μm in diameter. The resulting structure is 100% para- crystalline, with molecular chains running parallel to the axis of the filaments. It is this high degree of orientation that contributes to the extraordinary properties of Twaron® yarns.
Converting to staple and short-cut fiber
To produce Twaron® staple fiber, the continuous filament yarns are crimped, and can be treated with a finishing agent. After drying, the yarns are cut to the desired length. Twaron® short-cut fibers are produced by cutting the continuous filament yarns to the specified length. What’s more, short-cut fibers can also have additional finishing agents, depending on the application requirements.
The following converting possibilities are not shown in the picture. High linear densities of Twaron® continuous filament yarns can be produced by assembling yarns to customer specifications. Additional functional coatings can also be applied to Twaron® yarns in order to optimize the value-in-use of these products. The untwisted continuous filament yarns can be twisted to optimize fit-for-use characteristics.
Converting to pulp
To produce Twaron® pulp, the filament yarns are first cut, suspended in water and fibrillated. The pulp is then either packed directly and marketed as wet pulp or dehydrated and dried for sale in the form of dry pulp.
Twaron® Filament yarn
Twaron® filament yarn can be supplied in a wide range of mechanical properties. A simple categorization of the available yarn types is:
- Standard modulus / high elongation
- High modulus
- High tenacity
Twaron® filament yarn has proven its performance and added value in numerous applications, including optical fiber cables, hoses, tires, rubber products, ballistic protection, protective clothing, ropes and cables, composites and belts. Twaron® filament yarns are available in linear densities starting as low as between around 400 to around 800 dtex, depending on the type of yarn. Twaron® filament yarns can be combined to high linear density yarns or cords. The properties can be tuned to the application requirements by
using untwisted yarn or twisted cord constructions. Twaron® filament yarn types can be further differentiated by applying special surface treatments that add functionalities to the Twaron® yarn. These functionalities improve the product performance in an application and/or the processability. Examples of this include the application of the water- blocking finish on high modulus Twaron® yarn for optical fiber cables and the adhesion activation finish for rubber products.
Twaron® filament yarn is available in the regular yellow color of para-aramid material. Additionally, certain Twaron® filament yarn types are available in black. Black Twaron®
is used in applications where special requirements exist regarding the appearance of the yarns. Specifically, black Twaron® is used in applications such as composite fabrics, boat sails and protective clothing. The black color is created by dope-dying, resulting in good color fastness.
Twaron® Staple fiber
Twaron® staple fibers are used in textile applications for gloves, and for apparel that protects against heat and cuts. The staple fibers are available in the regular yellow para-aramid color as well as in black. Several specified staple fiber lengths can be supplied (40, 50, 60 mm). In addition, a various-cut staple fiber product is available with fiber lengths of between 76 mm and 100 mm. The linear density of the staple fibers can be selected from 0.9, 1.7 and 2.5 dtex products. For black staple fibers, linear densities of 1.7 and 2.5 dtex are available. Next to the staple fibers, Twaron® can also be supplied as stretch broken yarns.
Twaron® Short-cut fiber
Twaron® filament yarn can be converted into short-cut fibers or dipped chopped fibers with fiber lengths of between 0.25 mm and 12 mm for use in, for instance, engineering plastic applications.
Twaron® is available in powder form, specified by the particle size. Applications can be found in engineering plastics, coatings and rubber compounds.
To produce pulp, Twaron® filament yarn is first cut, suspended in water and then fibrillated. The characteristic properties of pulp are determined by the fibril length and the specific surface area, which is a measure of the amount of fibrillation.
Due to its chemical and physical properties, Twaron® pulp improves stability and increases the strength of compounds in which it is used.
To help our customers find optimal solutions, both dry and wet pulp options are available in various fibril lengths and in varying degrees of fibrillation. These options are available across a wide range of different applications, including friction products, sealing materials and specialty paper products.