Rubber toughening and damage competition theory. In material selection it is important to look at the interaction between the matrix and the secondary phase. For example, crosslinking within the rubber phase will promote high strength fibril formation that will toughen the rubber, preventing particle fracture. Carboxyl-terminated butadiene-acrylotnitrile (CTBN) is often used to toughen epoxies, but using CTBN alone increases the toughness at the cost of stiffness and heat resistance. Amine-terminated butadiene acrylonitrile (ATBN) is also used. Using ultra-fine full-vulcanized powdered rubber (UFPR) researchers have been able to improve all three, toughness, stiffness, and heat resistance simultaneously, resetting the stage for rubber toughening
Flowers of sulfur show that flowers of sulfur acts a fungicide, insecticide, and fumigant, as well as an agent in the treatment of numerous skin diseases. Flowers of sulfur Flowers of sulfur (older British spelling flowers of sulphur) is a very fine, bright yellow sulfur powder that is produced by sublimation and deposition. It is known as ' by apothecaries and in older scientific works. Natural sulfur was also known as brimstone, hence the alternative name flowers of brimstone. Flowers of sulfur were traditionally produced by subliming naturally occurring sulfur, known as "sulphur vivum". Impurities and moisture could cause acid residue in the