Increasing the ratio of bisphenol A to epichlorohydrin during manufacture produces higher molecular weight linear polyethers with glycidyl end groups, which are semi-solid to hard crystalline materials at room temperature depending on the molecular weight achieved. Structure of bisphenol-A diglycidyl ether epoxy resin: n denotes the number of polymerized subunits and is typically in the range from 0 to 25
WHAT IS THE ONE MINUTE CURE SERIES
Devoe & Raynolds, which was active in the early days of the epoxy resin industry, was sold to Shell Chemical the division involved in this work was eventually sold, and via a series of other corporate transactions is now part of Hexion Inc. In 1946, Sylvan Greenlee, working for the Devoe & Raynolds Company, patented resin derived from bisphenol-A and epichlorohydrin. Ciba's epoxy business was spun off as Vantico in the late 1990s, which was subsequently sold in 2003 and became the Advanced Materials business unit of Huntsman Corporation of the United States. of Switzerland, which went on to become one of the three major epoxy resin producers worldwide. Claims of discovery of bisphenol-A-based epoxy resins include Pierre Castan in 1943. Ĭondensation of epoxides and amines was first reported and patented by Paul Schlack of Germany in 1934. The health risks associated with exposure to epoxy resin compounds include contact dermatitis and allergic reactions, as well as respiratory problems from breathing vapor and sanding dust, especially when not fully cured. Epoxy has a wide range of applications, including metal coatings, use in electronics/electrical components/LEDs, high tension electrical insulators, paint brush manufacturing, fiber-reinforced plastic materials, and adhesives for structural and other purposes. Reaction of polyepoxides with themselves or with polyfunctional hardeners forms a thermosetting polymer, often with favorable mechanical properties and high thermal and chemical resistance. These co-reactants are often referred to as hardeners or curatives, and the cross-linking reaction is commonly referred to as curing. The IUPAC name for an epoxide group is an oxirane.Įpoxy resins may be reacted ( cross-linked) either with themselves through catalytic homopolymerisation, or with a wide range of co-reactants including polyfunctional amines, acids (and acid anhydrides), phenols, alcohols and thiols (usually called mercaptans). The epoxide functional group is also collectively called epoxy. Epoxy resins, also known as polyepoxides, are a class of reactive prepolymers and polymers which contain epoxide groups. Structure of the epoxide group, a reactive functional group present in all epoxy resinsĮpoxy is the family of basic components or cured end products of epoxy resins.
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