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
Polymer capacitor polymer e-caps in which a solid conductive polymer forms the electrolyte, this is much more difficult to achieve, because its conductivity comes by a chemical process of polymerization. However, the benefits of a solid polymer electrolyte, the significantly lower ESR of the capacitor and the low temperature dependence of the electrical parameters, in many cases justify the additional production steps as well as higher costs. Electrolytic capacitors with the charge transfer salt tetracyanoquinodimethane TCNQ as electrolyte, formerly produced by Sanyo with the trade name "OS-CON", in the true sense of the term "polymer" were not "polymer capacitors". TCNQ electrolytic capacitors