Semi-Ebonite Rubber

Since the flow causes sliding abrasion at a low angle of incidence in the piping, the rubber which can be suggested for this application is a low durometer hardness (40 on the Shore A scale) natural rubber. For lower flow rates at ranges of 1,200 litres per minute up to 4,000 litres per minute, a hard rubber or a semi-ebonite rubber can be used since the abrasive wear of the finely meshed particles will be negligible. 

Flexible Ebonite This can be called semi-ebonite usually loaded with mineral fillers with a lower proportion of sulphur, say 15 phr, and by incorporating into the compound synthetic rubbers like polychloroprene, polyisobutylene or butyl rubber. This ebonite will have good resistance to impact. A sheet made of flexible ebonite will look like a hard flexible leather. 

Halogens HF absorbers, fluoride dryer, centrifuges Natural rubber, ebonite, semi-ebonite... 

Pharmaceutical Crystallisation tanks, centrifuges, digesters Semi-ebonite and butyl rubber... 

These filters were used in illmenite beneficiation and titanium dioxide plants. These and their parts like agitators, troughs etc., were lined with a semi-hard flexible ebonite of natural rubber to protect the equipment against the abrasive action of the ore and solid particles in the slurries. 

There are basically six types of crosslinking mechanisms for NBR elastomers, very high sulfur for a special ebonite, normal sulfur, semi-EV (semi-efficient vulcanization or low sulfur systems), EV (efficient vulcanization with sulfur donors alone), peroxide and zinc oxide/peroxide for carboxylated nitrile. The innumerable combinations that can and are used are as numerous as there are rubber chemists in the world, but with care they all work in any given application. 

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