Gaskets made from white nitrile rubber won’t impart any taste to food. That’s one reason they’re used in food and beverage production but it’s not the material’s only useful property. Here’s a look.
Understanding White Nitrile Rubber
White nitrile rubber – chemical name Acrylonitrile Butadiene – carries the ASTM designation NBR and is sometimes referred to as white Buna-N. A blend of neoprene and SBR, white nitrile rubber is an abrasion-resistant elastomer. Shore hardness is around 60, putting it somewhere between tire tread and a pencil eraser, making it firm yet flexible.
White nitrile is usable over temperatures from around -40°F to 220°F (-40 to 105°C.) It resists attack by oils, fats, greases and hydraulic fluids although it is vulnerable to ozone, ketones, esters and aldehydes. (These were explained in a previous blog post, “Ketones and Gasket Materials”.)
Nitrile rubber is produced in a range of colors, but white nitrile is, as the name suggests, white. This gives it some useful applications.
Applications for White Nitrile Rubber Gaskets
As it doesn’t mark surfaces or impart a taint, white nitrile is available in grades approved by the FDA for food use. It’s also non-allergenic. Consequently, white nitrile gaskets are common in food and beverage production as well as pharmaceuticals.
White nitrile rubber is also used in applications where appearance matters. The smooth white finish is often desirable, especially in medical applications, and has a secondary benefit: it shows up leaks that would be unseen against dark materials.
In addition to sealing and gasketing applications, white nitrile is used for cushioning and protection. You may see it as liner in food processing equipment and also as bumper protection strips. A less obvious, though still common application, is for food grade rubber scrapers.
Talk to Hennig Gaskets & Seals
Gaskets for food and pharma use must comply with FDA requirements. White nitrile is often a good choice for such applications, although it has other uses too. As an attractive, non-marking material it works well in situations where appearance matters. Learn more by talking to our specialists.