Fiber Skeleton to Deliver a New Standard of Performance
Xencor™ long fiber compounds are created using a pultrusion process, where continuous reinforcement fiber strands are impregnated with plastic resin and trimmed to the targeted granulate length of typically 7 to 9 mm. These materials are reinforced with glass fibers, with lengths corresponding to the granulate length.
The function of LFTs is to create, during the injection molding process, a unique 3D entangled long fiber network inside the molded part (shown below), which sustainably improves the thermal-mechanical properties compared to traditional highly filled short-fiber plastics.
As the fibers are interlinked to each other, they actively participate in the energy transfer and absorption when stresses are applied to the molded part. Consequently, changes in properties in dependence of temperature, moisture or deformation speed are significantly reduced pushing forward the limits of utilization of the part.
Benefits of Xencor™ Long Fiber Compounds over Short Fiber Compounds
Distinctive Properties
Outstanding Stiffness Retention at High Temperatures
The fiber skeleton created in the molded article actively limits the effect of resin softening above glass transition of the plastic material and thus significantly improves the retention of performances at high temperatures.
Unrivaled Impact & Crash Resistance, even at Low Temperatures
Xencor™ LFT grades are extremely resilient materials. The active participation of the fiber skeleton in impact energy dissipation and in the inhibition of crack propagation provides a unique positioning for Syensqo LFT grades in terms of their stiffness/toughness combination. This makes Xencor™ LFTs excellent candidates for metal replacement in structural applications or applications needing to withstand crash impact and high-speed stress.
Impact Performances for Xencor™ PARA grade
Falling Weight Impact Test - Xencor™ PPA
PTI-CEAST - 23°C - 28.5 J Impactor
Very Low Creep
The creep resistance of Xencor™ LFT compounds is superior to that of most high-performance polymers with similar fiber content and is definitely a key advantage for parts operating under constant loading cases.
Graph compares strain evolution of specimen maintained under load.
The fiber skeleton significantly limits the initial part deformation that occurs after load application as well as the increase in deformation over time.
Very high dimensional stability
The coefficient of linear thermal expansion (CLTE) of Xencor™ compounds is low and more isotropic. It can be similar to that of many cast metals and alloys at room temperature. Low mold shrinkage and the ability to maintain tight tolerances allow for high reproducibility.
Processing
Xencor™ grades are supplied in 25kg bags and octabins. It is recommended that the material be stored in a cool, dry place with no direct sunlight. It is also recommended to dry Xencor™ grades prior to processing on the molding equipment.
Xencor™ can be used on standard injection machine equipment. Simply, low shear conditions must be preferred in order to minimize unnecessary fiber filament breakage. Pellet design has been optimized to ensure optimal feeding performances on the molding machine.
