ExxonMobil Chemical has introduced a new softer version of the Santoprene™ thermoplastic vulcanizates (TPV) that bond with engineering thermoplastics (ETPs). Santoprene TPV 45 B100 is the latest addition to ExxonMobil Chemical‘s rapidly expanding bonding portfolio which now includes 25 Santoprene TPV grades that bond with ETPs, nylons, metals and various polyolefins. With demand increasing, additional bonding grades are in development.
“We have had specific requests from OEMs and product designers in the computer peripherals, cell phone, personal care and stationery products sectors for an even softer, more tactile version of the Santoprene TPV grades that bond with ETPs. Importantly, they want this extra softness to be combined with the physical properties that only a true TPV material can provide,” said Bill Ramsey, global marketing segment manager, Santoprene brand TPVs.
This new softer Santoprene TPV has been designed for applications which require a very soft touch feel and strong bonding to ETP materials including polycarbonate (PC), acrylonitrile butadiene styrene (ABS), acrylonitrile styrene acrylate (ASA), acrylic (PMMA) and polyethylene terephthalate (PET). An advantage of this Santoprene TPV grade is its processing performance. With good mold design, better looking components can be produced with fewer flow marks.
This softer Santoprene TPV retains its high quality performance properties in various environments including hot air, oil and aqueous solutions. Properties include: long-term sealability and high bond strength to extend the product lifetime; a durable slip-resistant, soft touch feel; chemical resistance; and, minimal high temperature deformation.
In overmolding applications, the new grade eliminates the need for adhesives, bonding agents and physical or mechanical interlocks. This reduces processing steps which can improve product development cycle times and reduce system costs. Additional benefits include easy colorability, design flexibility and improved appearance.
“We understand the growing market requirements for TPVs, as opposed to uncross-linked TPEs, which can bond to a variety of different substrates using either two-shot injection molding or insert molding processes. The fully cross-linked nature of TPVs provides distinctive physical properties and, because they bond without the need for third-party agents, they can bring applications to market faster and reduce system costs,” said Ramsey.
As a result of this growing trend, this developmental Santoprene TPV is the latest of twelve bonding grades that ExxonMobil Chemical has introduced in the past twelve months.
The Santoprene™ TPV B150 ETP-bonding grades, launched last June exhibit exceptional bond strength. Even at thicknesses of less than 1mm, the cohesive bond is stronger than the materials themselves. And because the overmolded material can be so thin, the B150 grades are increasingly being used as an alternative to soft-touch paints. These grades also have been overmolded onto PC inserts for automotive applications such as tail lights. “Since these grades were introduced, market demand has been well beyond our expectations,” said Ramsey.
Another ETP bonding grade of Santoprene™ TPV complies with U.S. Food and Drug Administration (FDA) regulations for food contact. The new grade is suitable for many types of applications which come into contact with food and liquids including kitchen utensils, cutlery, blenders and processing equipment, food storage containers, small kitchen appliances such as toasters, kettles and microwaves, and caps, seals and closures.
For the automotive market, Santoprene TPV 65 B200, bonds to thermoplastic elastomers (TPE) and EPDM rubber profiles. This grade is designed primarily for glass run channel corner molding applications. Exhibiting excellent compression set for good sealing performance, the grade also has good melt flow properties to produce a glossy, smooth finish which can help harmonize the look of a car.
All of ExxonMobil Chemical’s bonding grades are available globally ensuring consistent product quality for customers wherever they are located.