Search results
Results from the WOW.Com Content Network
Curing is a chemical process employed in polymer chemistry and process engineering that produces the toughening or hardening of a polymer material by cross-linking of polymer chains. [1] Even if it is strongly associated with the production of thermosetting polymers , the term "curing" can be used for all the processes where a solid product is ...
In vulcanization, sulfur is the cross-linking agent. Its introduction changes rubber to a more rigid, durable material associated with car and bike tires. This process is often called sulfur curing. In most cases, cross-linking is irreversible, and the resulting thermosetting material will degrade or burn if heated, without melting.
Unlike other crosslinking agents, aldehyde-induced crosslinking is an intrinsically reversible process. NMR structure of these types of agents as interstrand crosslinks show that a 5'-GC adduct results in minor distortion to DNA, however a 5'-CG adduct destabilizes the helix and induces a bend and twist in the DNA.
An exothermic thermite reaction using iron(III) oxide. The sparks flying outwards are globules of molten iron trailing smoke in their wake. Some examples of exothermic processes are: [14] Combustion of fuels such as wood, coal and oil/petroleum; The thermite reaction [15] The reaction of alkali metals and other highly electropositive metals ...
An energy profile of an exothermic reaction. In an exothermic reaction, by definition, the enthalpy change has a negative value: ΔH = H products - H reactants < 0. where a larger value (the higher energy of the reactants) is subtracted from a smaller value (the lower energy of the products). For example, when hydrogen burns: 2H 2 (g) + O 2 (g ...
Therefore, by definition, the transition state for tertiary reactions will be at a lower energy than for secondary reactions. However, the BEP principle cannot justify why the energy is lower. Using Hammond's postulate, the lower energy of the tertiary transition state means that its structure is relatively closer to its reactants R(tertiary)-X ...
Also called Indianite. A mineral from the lime-rich end of the plagioclase group of minerals. Anorthites are usually silicates of calcium and aluminium occurring in some basic igneous rocks, typically those produced by the contact metamorphism of impure calcareous sediments. anticline An arched fold in which the layers usually dip away from the fold axis. Contrast syncline. aphanic Having the ...
Cross-linking may refer to Cross-link, a chemical bond of one polymer chain to another; Corneal collagen cross-linking, a parasurgical treatment for corneal ectasia ...