Sep 27 2007
ExxonMobil Chemical Company has introduced a new family of fast cycling Santoprene™ thermoplastic vulcanizate (TPV) grades which can be used to replace thermoset rubber and thermoplastic elastomers (TPEs) in “thick, chunky” applications. The new grades can reduce processing time by 20 to 30 percent, improving productivity and enhancing profitability while maintaining performance. Typical “thick” components include plugs, bumpers, grommets, gap fillers, spacers and motor mounts in industrial and automotive applications.
The fast cycling time of Santoprene TPV M500 generates a number of benefits for processors molding parts with cross sections more than 2mm thick. These benefits include: increased molding capacity with existing equipment and tooling; reduced tooling costs as fewer cavities are needed to produce the target volumes; reduced overall part cost by requiring less machinery time per part; and postponement of capital investment in new machinery because of increased production.
Injection molding time typically represents at least 50 percent of total part cost. The portion of the injection molding process with the biggest opportunity for improvement is part cooling, as it takes 30 to 80 percent of the total cycle time depending on part thickness and tooling complexity.
“Injection molders are facing pressure to reduce costs while maintaining performance. Thicker parts generally have longer cycle times so by using Santoprene TPV M500, which processes up to 30 percent faster, molders can achieve higher production efficiency and lower overall part costs. The potential for significant cost reductions is particularly good when production quantities are high,” said Dru Kefalos, global marketing manager, ExxonMobil Chemical specialty elastomers.
With a higher recrystallization temperature than competitive materials, this new TPV allows faster ejection from the mold.
“Thick parts made of thermoset rubber can now be replaced due to the improved substitution economics of Santoprene TPV M500, creating new opportunities for molders,” said Kefalos.
Available in three different levels of hardness (Shore 55, 65 and 80), Santoprene TPV M500 is a black, UV-stable, high flow grade material that can be demolded significantly faster than conventional TPVs.