New Polyethylene Compounds For Rotomolding Increase Output

Replacing Conventional Medium-Density PE, New TekTuff™ SPA Compounds Enable Heritage Kayaks to Reduce Kayak Weight by while Producing More Kayaks per Shift

Lodi, OH — A new generation of TekTuff™ advanced polyethylene rotational molding compounds provides the same resin-saving capabilities as standard TekTuff products but requires an average of 12.5% less oven time to melt, fuse, and develop optimum physical properties in the mold, it was announced at Rotoplas by Teknor Color Company (Booth 631). The new TekTuff compounds also exhibit a broader processing window, providing greater latitude in molding conditions without compromising property development.

Designated TekTuff SPA, the improved products yield parts that are substantially stronger and stiffer than parts of similar thickness molded of conventional metallocene-based medium-density PE, opening the opportunity for molders to reduce part weight by 10 to 15%, according to Gretchen Leighliter, senior technical service engineer. This resin saving is similar to that obtained with standard TekTuff compounds, introduced by Teknor Color in 2002.

Standard TekTuff processes similarly to conventional medium density PE, noted Leighliter. "The 12.5% shorter oven time that is typical with our new TekTuff SPA products translates into a reduction in the overall molding cycle of roughly 10%," she said. "Molders benefit by saving on increasingly costly energy or by producing 10% more sellable product per working shift. In addition, TekTuff SPA products are more 'forgiving' than standard TekTuff compounds, making it easier to achieve target physical properties."

Reports confirming these benefits have come from several customers, including Heritage Kayaks, which rotomolds kayaks in seamless hull-and-deck units at its 70,000 sq.ft. (6,500 sq.m) plant in Bristol, RI. Depending on model, the kayaks weigh 37 to 73 lb. (17 to 33 kg).

"Because TekTuff SPA is so much stiffer than the conventional medium-density PE we have been using, we have reduced the weight of certain models by 9% and still maintain the high level of toughness for which our products are well-known," said Heritage Kayaks chief operating officer Carolyn Shea. "At the same time, we have achieved reductions in cycle time of at least 10% in certain ovens, which for us means production of roughly six to nine kayaks per shift instead of five to eight. In addition, our production staff reports reductions in reject rates. We plan to shift completely to TekTuff SPA for all our products."

Besides watercraft, Teknor Color Company recommends TekTuff SPA for other rugged-use applications, including tanks and containers, playground toys, and transportation and agricultural items formerly produced from fiberglass. TekTuff SPA compounds are available in natural form or as ready-to-mold custom-precolored formulations.

SOURCE: Teknor Color Company