Sumitomo Chemical to Unveil New Family of LFT Liquid Crystal Polymers

 Sumitomo Chemical Advanced Technologies has developed and will soon commercialize a new family of long-fiber thermoplastic (LFT) compounds with high-performance liquid crystal polymer (LCP) matrices reinforced with 13-mm chopped carbon fiber or fiberglass.

Enhancing the Thermal and Mechanical Performance:

The new materials are currently undergoing customer evaluations in several industries and developmental quantities of two grades — SUMIKASUPER™ SCG-379 with 30-50% fiber-weight fraction (FWF) E-glass and SUMIKASUPER™ SCG-420 with 30-40% FWF high-modulus carbon fiber — are available to interested parties for testing.

An LCP matrix and the option for carbon fiber reinforcement will significantly upgrade the thermal and mechanical performance available from LFT technology and the products are being targeted to replace alloys of aluminum and magnesium as well as steel.

The vast majority of all commercial LFT products feature fiberglass-reinforced polypropylene (PP), although higher temperature polyamide 6 and 6/6 (PA6, PA6/6) have been gaining market share in this segment.

Beyond automotive, which still consumes the majority of LFT materials, the products have expanded into applications in the sporting goods, power tool, and appliance industries. And commercial carbon fiber reinforced LFT grades are available in PP, PA, thermoplastic polyurethane (TPU), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), and polyethersulfone (PES).

The new LFT-LCPs grades have been under development for four years. The most challenging issue to overcome was finding the right fibers to maximize the performance of the LCP compounds.

“It has long been established that mechanical properties of plastics increase with longer fiber lengths,” explains Takayuki Sugiyama, Sumitomo product manager. “However, it also is well known that rarely do fibers longer than 2 mm survive the screw, runners, and gates to make it into the mold and the molded part during the injection molding process. Therefore, the advantage of starting with significantly longer fiber reinforcement in LFT materials is not being fully realized.”

Source: Sumitomo Chemical/Omnexus