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Epoxy is the family of basic components or cured end products of epoxy resins. Epoxy resins, also known as polyepoxides, are a class of reactive prepolymers and polymers which contain epoxide groups. The epoxide functional group is also collectively called epoxy. [1] The IUPAC name for an epoxide group is an oxirane.
Paper Coating 1) The paper or board 2) The first layer of coating to even out the surface 3) A second layer for an even smoother and whiter surface. Pigments that absorb in the yellow and red part of the visible spectrum can be added. As the dye absorbs light, the brightness of the paper will decrease, unlike the effect of an optical ...
Sand is added to improve compressive strength, hardness and reduce shrinkage. The binding property of clay is also used widely to prepare shaped articles (e.g. pots and vases) or to bind solid pieces (e.g. bricks). In composite materials, epoxy, polyester or phenolic resins are common.
This is because there is no physical difference between soft clay and the same clay as a soft paper clay, except the addition of a small percentage of tiny inert cellulose fibers. However, using less fiber in paper clay on the potters wheel is recommended, particularly if the leather hard work is to be trimmed on the wheel.
Araldite adhesive sets by the interaction of an epoxy resin with a hardener. Mixing an epoxy resin and hardener together starts a chemical reaction that produces heat – an exothermic reaction. [2] It is claimed that after curing the bond is impervious to boiling water and to all common organic solvents.
After evaporation of the solvent, a solid compound is formed. Chemical bonds are also important in certain adhesive / substrate combinations, for example when bonding glass using silicone adhesives, wood using polyurethane adhesives and aluminium using epoxy adhesives. Chemical bonding leads to significantly higher adhesion than physical bonding.
A generic epoxide. In organic chemistry, an epoxide is a cyclic ether, where the ether forms a three-atom ring: two atoms of carbon and one atom of oxygen.This triangular structure has substantial ring strain, making epoxides highly reactive, more so than other ethers.
Epoxy resins are typically cured by the use of additives, often called hardeners. Polyamines are often used. The amine groups ring-open the epoxide rings. In rubber, the curing is also induced by the addition of a crosslinker. The resulting process is called sulfur vulcanization.