New use for super-tough plastics: kids’ toys

K’NEX’ Industries’ world renowned construction sets, with their signature plastic rod and connector building pieces, are manufactured with Ticona’s Celcon acetal copolymer.

While small amounts of high-performance engineering plastics have been used in toys before — primarily for joints, like the moving limbs of action figures — Ticona believes K’NEX construction sets are the first toys to be made almost entirely of higher-quality engineering plastics.

A toy designed to be built, dismantled and rebuilt into different structures needs extremely strong and resilient components, molded to exacting tolerances. “For the connector in a K’NEX toy to work, the tolerances have to be extraordinarily tight, plus or minus one or two thousandths of an inch. And the pieces would have to endure endless snap fits while still providing a tight grip on the connector rods,” says Joel Glickman, creator and founder of K’NEX toys and head of The Rodon Group, an injection molder in Hatfield, PA.

The Rodon Group considered standard plastics like polyethylene and polystyrene, but the necessary properties of lubricity (slipperiness), resilience, creep (distortion under a sustained load), wear resistance and tensile strength could be found only in Ticona’s Celcon acetal copolymer.

Ten years ago, high-performance engineering plastics like Celcon were relative strangers to the $12-billion toy business. Now, 80% of all toys contain plastics — the industry uses more than a billion pounds annually, most of it recycled or commodity plastics like polystyrene, polyethylene or polypropylene, according to Ticona.

As toys became more complex, the plastics that went into them had to demonstrate greater strength and flexibility. Ticona reports that nylon, PMMA, polycarbonate and polyurethane are now being used when their specific performance characteristics are needed. Ticona’s Celcon, for example, is also used on Boomerings Links, colorful chain links aimed at pre-schoolers.

Ticona 800-833-4882