New Foamable TPVs Provide Effective Seals in Door and Window Profiles While Avoiding Complications Posed by Urethane Seals

July 16, 2018

Teknor Apex Designed the New Sarlink® TPVs Specifically for Low-Density Foams and Supplies Other TPE Options for Foam and Skin Segments of 3-Component Profiles 

PAWTUCKET, RI, U.S.A., July 16, 2018: A new series of thermoplastic vulcanizate (TPV) compounds from Teknor Apex Company exhibits the high resilience required for door and window seals and provides effective alternatives to widely used thermoset polyurethane foams.

Available from 40 to 70 Shore A, the Sarlink® 8100 series can be foamed to a density of 0.20 g/cm3 range, which is comparable to those of urethane foam used in door seals but is difficult to achieve with standard TPEs. As TPVs, they exhibit lower compressive set than standard TPEs, providing more of the resilience needed to withstand the repeated opening and closing of doors. The new compounds can be foamed using both chemical and physical blowing agents and, unlike urethane foams, are processed in standard equipment for thermoplastics. 

In other key differences from urethanes, TPVs do not require a curing step, are recyclable, and do not present concerns about isocyanate monomer.

Door and window profiles for sealing are typically three-layer structures, with a skin layer providing protection and good appearance, the foam layer, and a rigid component such as polypropylene (PP). The Sarlink 8100 series of TPVs adhere well to, and can be coextruded with, other TPVs, TPOs, and PP. In addition, Teknor Apex supplies harder TPVs that serve as skin materials. The company can also custom-formulate foamable grades of TPVs or styrenic TPEs.

“These foamable materials are the latest additions to a portfolio of more than 30 TPE and TPV grades that Teknor Apex has developed specifically for building seal applications,” said Tom Foley, senior market manager. “Our goal is to provide customers with a wide range of options reflecting the variety of door and window constructions and to serve as a single source for multiple seal applications.”

In addition to the new foamable products, TPEs and TPVs available from Teknor Apex for seal applications in building products include extremely soft grades, abrasion-resistant materials, compounds for rigid components, general-purpose TPVs with excellent melt elasticity, high-performance TPVs with optimal surface appearance, low-friction slip coating grades, and TPEs for structural seals.  

 

Typical Properties of 45A Foamable TPV for Door and Window Seals

Properties and Units ASTM Test Sarlink® 8145 Foamable TPV
Hardness (5 s del) Shore A D2240 47
Specific gravity (unfoamed) D792 0.92
Tensile strength psi (mPa) D412 653 (4.5)
Elongation % D412 620
Compression set at 72⁰F (22⁰C) for 22 hrs % D395 17%
Brittleness temperature °C D746 < -40