MIDLAND, Mich.—DuPont Co.'s transportation and industrial unit and ExxonMobil Chemical's specialty elastomers business have developed new thermoplastic vulcanizates for automotive corner mold seals.
The two companies replaced traditional organic slip additives with DuPont's engineered silicone-based additives to develop the "next-generation" Santoprene TPV, they said a joint statement June 27.
Compared to its previous grades, the new TPV material offers improved bonding to EDPM rubber substrates and a lower coefficient of friction (COF) for the easy opening and closing of doors and windows.
The Santoprene TPV B260 family of products also delivers improved flow properties, abrasion resistance and ultraviolet light stability, the companies added.
The collaboration, according to Christophe Paulo, DuPont marketing manager, has "laid the foundation" for future projects using silicone technologies to solve industry challenges.
In response to customer demand, ExxonMobil Chemical sought to enhance the bonding of Santoprene TPV to EDPM rubber while increasing its sliding performance.
However, reducing the COF to increase sliding performance can negatively impact bonding, the company said.
To address that, ExxonMobil collaborated with DuPont to explore the use of its silicone-based additives.
"The DuPont development team found that synergies between a lower molecular weight silicone polymer and an ultra-high molecular weight silicone polymer delivered the low COF ExxonMobil Chemical was looking for," according to the statement.