To mark the 50th anniversary of Vistalon EPDM rubber, ExxonMobil Chemical has established an online toolkit of model formulations for application development. Available to customers, the digital formulary represents 50 ways for customers to meet industry specifications in a cost effective way. All formulations are designed for factory scale manufacturing and give the properties of the final compound. In addition, as proof that five decades of commercial success will continue on as markets evolve, ExxonMobil Chemical is also launching three new Vistalon EPDM rubber grades (Vistalon 2502, Vistalon 6602, Vistalon 7602 EPDM).
New applications, markets
When ExxonMobil Chemical opened its French plant in 1972, it became the first supplier of EPDM to manufacture product in more than one region. Recognizing that Asia provided huge growth opportunities, the company joined Japan Synthetic Rubber and Korea Kumbo Petrochemical as shareholders in a manufacturer based in Korea. It also began producing Japan Synthetic Rubber grades at its Baton Rouge plant to supply Japanese automotive manufacturers that were building plants in the United States and needed a local source of parts.
In the 1980s, Vistalon EPDM grades were developed to provide impact modification for plastics. Vistalon EPDM modified polypropylene grades were the first generation of TPOs, which eventually drove the conversion from chrome to plastic bumpers on cars and later to painted plastic bumpers. Subsequently, the EPM modifiers were replaced with another family of elastomers from ExxonMobil Chemical (Exact plastomers).
At the same time as TPOs were being developed, thermoplastic vulcanizates (TPVs) were developed in which the rubber phase was cross-linked within the PP matrix. Vistalon EPDM has always been the building block from which Santoprene TPV products are made. Today, ExxonMobil Chemical notes that TPVs are an important segment for EPDM as customers seek ways to fabricate elastomeric parts using lower cost plastic processing equipment.
A brief history
- 1937: Butyl rubber introduced.
- 1961: Vistalon 404 rubber launched, wins applications in high voltage electrical applications because of its long service, due in part to the fact that it did not degrade in the presence of moisture.
- 1962: Methylene norbornene successfully synthesized as a third monomer in the rubber, allowing the material to retain ozone and environmental resistance and be cured using conventional sulfur vulcanization.
- 1963: Commercial production of EPDM rubber begins in May at the Baton Rouge plant, with what was eventually called Vistalon 4608 rubber. This material enabled sulfur vulcanization and low-cost compounding for a range of molded and extruded goods, with early applications in garden hoses, radiator seals and drain hoses for washing machines.
- 1966: Available butyl rubber capacity in Baton Rouge converted to EPDM production.
- 1967: Third EPDM monomer changed from methylene norbornene to ethylidene nobornene, because it enabled the use of a wide range of catalysts and achieved superior cure properties. This new diene eventually became the third monomer of choice for Vistalon EPDM products.
- Late 1960s - early 1970s: Vistalon EPDM rubber's processability and cost benefits embraced by an industry that had been used to batch-processing equipment originally designed for natural rubber and styrene butadiene rubber. In automotive, new grades offered significant quality improvements, with Vistalon replacing styrene butadiene rubber for window channels and weatherseals, and chloroprene and butyl rubber in radiator hoses, which could now last as long as the car.
- 1972: Growing demand in Europe, which had been supplied from Baton Rouge, led to the construction of a new facility at Notre Dame de Gravenchon (NDG), in France.
- 1975: Capacity at the NDG plant increased 40% in response to demand growth.
- 1989: The first commercial grades of EPDM rubber that had been manufactured using proprietary tailored molecular weight distribution technology were introduced. Vistalon 7500 EPDM and Vistalon 8600 EPDM were launched in Europe for molded and extruded goods.
- Mid 1990s: A new third monomer, vinyl norbornene, used to further enhance electrical and heat resistance, and to increase extrusion rates due to its fast cure rate and smooth surface finish.
- 2003: New plant added in Baton Rouge, which was the first to utilize metallocene catalysts to produce EPDM. Relative to the conventional Ziegler-Natta catalysts deployed since the 1960s, the new catalysts allowed greater control of the molecular structure.
- 2012: A new 300,000 tons/yr elastomer plant in Singapore will be on stream, further increasing Vistalon EPDM rubber capacity. ExxonMobil Chemical and SABIC are also investigating new plants in Saudi Arabia, which would include Vistalon EPDM units.