ExxonMobil Chemical has introduced new grades of Santoprene™ thermoplastic vulcanizates (TPVs) that bond with nylon in cold insert over-molding applications. The new B500 grade family, which is colorable or black, has been developed for applications that require a very strong bond with nylon and high temperature resistance, such as power tools, kitchen tools, automotive applications, furniture and sporting goods. Exhibiting high bond retention values, the new grades enable the design and manufacture of nylon parts coupled with the quality performance properties of a TPV. These properties include long-term sealability; a durable slip resistant feel; excellent compression set; chemical, oil and heat resistance; and enhanced bond integrity to extend product life.
"The exceptional cohesive bond of these Santoprene TPVs enables overmolds as thin as 0.5 mm to be achieved. Competitive materials can require a thickness of at least 1.5 mm to attain a similar bond," said Bill Ramsey, market segment manager, ExxonMobil Chemical. "The new B500 grades are ideal for use in high-torque power tools which require reliable, non-slip grips, or in kitchen tools needing strong, heat resistant, soft touch handles. Automotive applications including heating and air-conditioning components and electrical seals benefit from an effective molding capability." The cold insert molding grades, available in Shore 60 and 75 A, can also generate new opportunities for processors of Santoprene TPVs. Previously, nylon bonding TPVs have required two-shot injection molding, which generally is more cost efficient for high-volume applications. "This latest addition to our bonding grade portfolio has been developed to provide molders with more economical processing options and to allow designers more flexible creativity," said Ramsey.