Rosemont, Ill. — Rotational mold maker Norstar Aluminum Molds Inc. has started a sister company, called 4Roto, to handle distribution of Rotoworx polypropylene compounds in North and South America.
4Roto and PSD Rotoworx had an exhibit at the Rotoplas show, next to Norstar's booth. Norstar President Sandy Scaccia said the company is importing the resin from Rotoworx, based in Sydney, Australia, and warehousing it in Norstar's factory in Middlefield, Ohio. Norstar and 4Roto are both based in Cedarburg, Wis.
The Rotoworx proprietary PP compound can be pulverized at ambient temperatures — so it does not have to be cryogenically ground.
That is a major breakthrough, said Ravi Mehra, head of business development at 4Roto. Cryogenic puliverizing adds cost to a pound of PP, he said.
Rotoworx has the material, made for it in Thailand, as powder or granules, in natural and black.
Mehra said the Rotoworx PP balances both stiffness and impact toughness. It also offers good stress crack resistance and stand up to vacuum much better than polyethylene, he said — making the PP attractive for tanks. Impact strength at high temperatures is similar to PE, he said.