Radiated PE boosts properties of pipe and film.

Polyethylene pellets that are partially crosslinked with radiation have been introduced by the IBA Advanced Applications div. of Ion Beam Applications SA, a Belgian company. The IBA companies, with U.S. headquarters in San Diego, offer Raprex PE rigid and flexible grades for extrusion and injection molding. IBA selectively crosslinks just the amorphous phase of HDPE, LDPE, and LLDPE pellets, says George Forczek, product manager. Crosslinking reportedly boosts mechanical properties to levels competitive with chemically crosslinked PE. Precise crosslinking keeps gels low and maintains reprocessability. IBA expects to offer powdered versions soon that may be suitable for rotomolding.

Among current offerings, Grade 100 is a modified HDPE for pipe, tubing, and profiles. The 0.950-g/cc material reportedly exhibits excellent pipe-burst and hoop-stress performance along with easy processing. Tensile strength at yield is 4350 psi, notched Izod impact strength is 8 ft-lb/in.

Grade 200, a modified HDPE for injection molding, is aimed at thin-wall tote bins, pump housings, clamps, and luggage handles. It has 0.950 density, 66 Shore A hardness, and enhanced wear resistance.

Grade 300, a modified LLDPE, is for use in monolayer, downgauged greenhouse film, protective sleeves for steel pipe and timber poles, and bubble wrap. Film shows tensile strength at yield that is 44% better in MD and 90% better in TD than unmodified LLDPE based on higher alpha olefins. Improved elongation, tear strength, and puncture resistance are also reported. Tel: [phone], www.iba-worldwide.com

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