Arkema, supplier of Rilsan-brand polyphtalamide (PPA), has extended the range of grades offered to include materials suitable for injection molding, rounding out what it claims is the first complete PPA-based product line. In March 2009 the supplier launched Rilsan HT for extrusion, and also offers materials for blowmolding. Rilsan HT resins, which are up to 70%-derived from renewable non-food-crop vegetable feedstock and, says Arkema, avoid the processing difficulty associated with PPA in the past, for instance moisture absorption and brittleness, with the HT grades offering processing characteristics similar to those of aliphatic polyamides. With mold temperatures close to those of PA12 and PA11, Rilsan HT can be processed on standard injection molding equipment using conventional water-cooled temperature control. Similarity in mold shrinkage properties also means Rilsan HT can be processed in injection molds designed for PA12 and PA11.

Arkma anticipates some of its injection moldable grades, which offer both ductility and conductivity, could see use in applications including fuel systems where conductivity is specifically required, as it is in the North American market. Grades are available glass-reinforced or formulated for conductivity.

The supplier claims that its Rilsan HT is the only PPA-based injection molding material that can be easily spin-welded with aliphatic high performance polyamides, offering processors further component integration options and helping to address safety and emission standards of pipe connections in fuel-conducting systems.  —[email protected]