For all the rest of us:
NBR is also known as Nitrile Rubber in the wire and cable industry and ESP stands for Electrical Submersible Pump Cable.
"Acrylonitrile butadiene rubber (NBR) is a family of unsaturated copolymers of 2-propenenitrile and various butadiene monomers (1,2- butadiene and 1,3-butadiene). Although its physical and chemical properties vary depending on the polymer’s composition of acrylonitrile (the more acrylonitrile within the polymer, the higher the resistance to oils but the lower the flexibility of the material), this form of synthetic rubber is generally resistant to oil, fuel, and other chemicals."
Contact The International Institute of Synthetic Rubber Producers, Inc. (Houston, TX) at
www.iisrp.com/
The major producers of NBR worldwide include:
Bayer (Canada, France)
Girsa (Mexico)
Hyundai (South Korea)
JSR Corporation (Japan)
Kumho (South Korea)
Nantex (Taiwan)
Nitriflex (Brazil)
PetroChina (China)
Petroflex (Brazil)
Polimeri Europa (Italy)
Zeon Chemicals (USA)
Zeon Chemicals (UK)
Zeon Chemicals (Japan)
You can also join the Rubber.com Email Forum for more research on distributors at
www.rubber.com/rubber/a/rb0530.html
Sincerely,
Peter J. Stewart-Hay
Principal
Stewart-Hay Associates
www.Stewart-Hay.com 
