Engineering plastics come in sheets and rollstock for thermoforming.

Penn Fibre Plastics (PFP) in Bensalem, Pa., has introduced a series of rollstock and sheet products based on engineering thermoplastics for thermoforming technical parts. The new Pennite line includes products based on nylon, acetal, ionomer, PPS, and PVDF.

"We've closed the circle on formable engineering thermoplastics," claims Michael Gehrig, PFP's general manager, who says previous formable grades of these materials were rarely successful in high-quality parts. Yet market potential for thermoformed engineering TPs is exploding due to the process' inherent advantages--lower tooling cost and shorter tooling lead times (typically seven weeks) compared with injection molding. Gehrig credits the recent development of high-melt-strength resins as well as thermoforming process refinements by processors like FreeTech Plastics in Fremont, Calif., and Magee Plastics in Warrendale, Pa. Recent achievements in materials and processing include the following:

* Nylon 6 and 66 resins supplied by Germany's Bayer AG offer continuous service temperature of 284 F, high strength, and excellent heat and chemical resistance for black, underhood automotive parts. Formable grades incorporate up to 25% glass. A 15%-glass grade has been adopted by FreeTech Plastics for a commercial auto air dam (see photo).

* Ticona's Fortron PPS resin offers service temperatures up to 400 F, high purity, and outstanding chemical resistance. Neat and glass-reinforced versions have been honed for thermoforming applications in semiconductors, chemical tank liners, and automotive uses.

* Solvay's Solef PVDF fluoropolymer has been tailored for highpretty semiconductor parts and liners for fiberglass-composite chemical tanks and oil and gas pipe.

* Thermoformable grades of DuPont Engineering Plastics' Hytrel copolyester TPE have Shore D hardnesses of 40 to 80 and contain flame retardants and heat and light stabilizers. They are aimed at under-hood gaskets and shrouds.

* DuPont's Delrin acetal homopolymer is available in formable unfilled, glass-filled, impact-modified, ESD, paintable, and printable grades. Specific processing parameters for forming acetal have been developed by German equipment supplier Adolf Illig Maschinenbau. Large glossy panels for tractor mowers and autos are targeted.

* Formable sheet based on DuPont's Surlyn ionomer are also offered, including Reflection versions that offer high gloss and weatherability in many vivid colors.

Pennite nylon, acetal, and ionomer come in rollstock 0.010 to 0.093 in. thick or sheet up to 0.250 in. thick and 48 in. wide. For other materials, gauges start at 0.010 in. Tel: [phone], www.pennfibre.com