SAN DIEGO — The Association of Rotational Molders is funding research to reduce cycle times and process engineering thermoplastic ABS as an alternative in the polyethylene-dominated rotational molding market.
Shorter cycle times could boost rotomolding vs. competing processes, and the availability of ABS might lead to rotomolded products with more scratch and impact resistance.
ARM President Carl Dobrzeniecki and Vice President James Leitz discussed industry needs and issues in an interview during the group's spring meeting, held March 18-20 in San Diego. Dobrzeniecki is president of Molding Co. in Farmington, Mo., and Leitz is vice president of marketing with Gregstrom Corp. in Woburn, Mass.
With existing cycle times, it is "tough to compete with blow molding or thin sheet or structural foam," Leitz said.
Last year, ARM contracted for a three-year, $207,000 project to reduce cycle times at two foreign universities.
"We are looking at the effect of fillers, reinforcing fibers [and] venting," said Roy Crawford, a professor at Queen's University of Belfast in Northern Ireland and ARM's volunteer technical services director.
Queen's University is focusing on computer simulation, and the University of Auckland in New Zealand is concentrating on heat-transfer issues.
Separately, an ARM-funded, $50,000 research project at Brigham Young University seeks an ABS resin that works in rotomolding.
Researchers will explore the potential of off-the-shelf resins Dow 342EZ and GE Cycolac BDT6500. Neither ABS contains a flame retardant.
BYU intends to place a student researcher in jobs at molding and compounding companies to "run full-scale tests with these two materials and try to identify a reasonable processing window," said research adviser A. Brent Strong, a professor at BYU in Provo, Utah.
Early BYU research focused on finding a replacement for the butadiene hydrocarbon in ABS; that search continues. Butadiene's carbon-carbon double bonds are susceptible to degradation by oxygen, especially at high temperatures.
BYU intends to press Dow Plastics and GE Plastics for technical assistance.
"We probably have not pursued that strongly enough," Strong said.
Rotomolders have problems getting ABS suppliers to develop different formulations.
"We are still a small part of the market," Leitz said.
ARM leaders underscored the need to educate industrial designers about rotomolding. John Fawcett, president of Fawcett Design Inc. of Kent, Ohio, ran a two-day seminar, and Warren Ginn, senior industrial designer with Integrated Design Systems Inc. of Great Neck, N.Y., appeared as the meeting's opening speaker.
As of Dec. 31, ARM had 469 member companies in 57 countries but no formal international structure. Membership outside North America accounts for about 40 percent.
Dobrzeniecki said ARM, which marked its 25th anniversary, is evaluating its international role."It is tough to serve people in Malaysia and South Africa and Germany" because of language barriers, Dobrzeniecki said. In some cases, in-country groups of rotomolders coalesce to deal with regulatory or legislative issues.
ARM's biennial Rotoplast has succeeded in reaching broad audiences, Dobrzeniecki said. Rotoplast '01 is set for Sept. 23-24, and ARM's fall meeting is Sept. 23-26. Both will be in Minneapolis.