Common types and properties of epoxy resin

I. Definition
1,
Epoxy Resin
is a high-molecular oligomer (Oligomer) that contains two or more epoxy-based organisms, such as fat, lipid or aromatic, and can be used to form useful thermo-cured products through epoxy group reactions. When the polymerization n is zero, it is called epoxy compound, referred to as epoxide. Although these low relative molecular mass resins do not fully meet the strict definition, they are collectively referred to as epoxy resins
Inlander China
because they have the basic properties of epoxy resins when
. The typical epoxy resin structure is as follows.2,
epoxy
is the characteristic group of epoxy resin, its content is the most important indicator of this resin. There are several different notations describing the epoxy-based content:
(1) epoxy equivalent:
refers to the mass containing 1mol epoxy resin, the epoxy equivalent of low relative molecular mass (molecular weight) epoxy resin is 175 to 200g/mol, as the molecular weight increases the chain between epoxy base, so the high molecular weight epoxy resin epoxy equivalent is correspondingly high.
(2) epoxy value:
(moles) of epoxy-based substances contained in every 100g resin. This method is beneficial to the measurement of curing agent dosage and the dosage. Because the amount of curing agent means the amount of curing agent added to every 100g epoxy resin (part perhundred of resin abbreviated as phr). China uses the physical amount of epoxy.
Epoxy equivalent s 100/ epoxy value
3, viscosity definition viscosity: the nature of internal friction generated between molecules when a liquid flows, called the viscosity of the liquid, the size of the viscosity is expressed by viscosity, is used to indicate the resistance factors related to the properties of the liquid.
two types of viscosity units:
1, lipo (cps)
2, millipas (m.pas)
1 millipas (cps) s 1 millipas (m. pas)
2, type and performance
1, BPA epoxy resin: bisphenol A (i.e. diphenol propane) type
epoxy resin i.e. diphenol propane shrinking glycelor ether. In epoxy resin its raw materials are easy to access, the lowest cost, so the largest output (in China accounted for about 90% of the total epoxy resin production, in the world about 75% to 80% of the total epoxy resin production), the most widely used, known as universal epoxy resin. The molecular structure of bisphenol A epoxy resin determines its performance with the following characteristics:
(1) is
thermoplastic resin
, but it has thermostic properties, can form a variety of high-performance curing substances with a variety of curing agents, catalysts and additives, almost to meet a variety of use needs.
(2) resin has good processability. When cured, it basically does not produce small molecular volatiles and can be molded at low pressure. It can be dissolved in a variety of solvents.
(3) curing has a high strength and bonding strength.
(4) curing has high corrosion resistance and electrical properties.
(5) curing has some toughness and heat resistance.
(6)
major
are: low heat resistance and toughness, wet heat resistance and poor weather resistance.
2, BPA F epoxy
: This is a new type of epoxy resin developed to reduce the viscosity of BPA epoxy resin itself and have the same properties. Liquid bisphenol F epoxy resins are usually produced by using
biophenol F (biphenol-based methane)
and epoxy propane to react under NaOH action.
bisphenol F epoxy resin is characterized by
ciscosity is small
, less than 1/3 of the viscosity of bisphenol A epoxy resin, good impregnation of fiber. Its curing material has almost the same performance as bisphenol A epoxy resin, but has slightly lower heat resistance and slightly better corrosion resistance. Liquid BPA F epoxy resins can be used in solvent-free coatings, adhesives, cast plastics, fiberglass and carbon fiber composites.
3, polyphenol-type shrinking glycelor ether epoxy resin
: polyphenol-type shrinking glycelyceride epoxy resin is a class of
multi-official group
epoxy resin. In its molecules there are more than two epoxy-based, so the curing material cross-link density is large, with excellent heat resistance, strength, mod, electrical insulation, water resistance and corrosion resistance.
4, adipose shrinking glycerin ether epoxy resin
: Adipose shrinking glycerin ether epoxy resin is by binary or polyol and epoxy chloropropane under the catalyst action of open cycloether, the production of chlorinated alcohol intermediates, and then react with alkali, deHCl closed ring, the formation of shrinking glycerin ether.
adipose shrinking glycery ether epoxy resin is made up of two or more epoxy-based and fat chain directly connected. There are no ring structures such as benzene rings, lipid rings and hem rings in molecular structures. The vast majority of these resins have very little viscosity, and most varieties are water-soluble, mostly long-chain molecules, so they are flexible. However
heat resistance is
poor.
5, shrinking glyceride epoxy resin
: shrinking glyceride epoxy resin is a type of epoxy resin developed in the 1950s, is the molecular structure of two or more shrinking glyceride-based compounds.
its
main features
are:
(1) small viscosity, good process. Can be used for pouring, encumeration, or as an active thinner.
(2) reaction activity is large, and the gel time is only about half that of bisphenol A epoxy resin.
(3) is soluble with other epoxy resins that they can be mixed to improve the performance of ordinary epoxy resins.
(4) high bonding strength and good mechanical properties of curing materials.
(5) has good resistance to ultra-low temperatures. It has a higher shear resistance than biphenol A epoxy resins at ultra-low temperatures from -196 to -253 degrees C.
(6) good electrical insulation, especially good trace resistance to leakage.
(7) surface gloss and light transmission is good.
(8) weather resistance is superior to BPA epoxy resins because they do not contain phenolic oxygen base in the molecule.
(9) the main
disadvantages
is the presence of ester bonds make water resistance, acid resistance and alkaline resistance is poor, heat resistance is also low.
6, shrinking glyceramine-type epoxy resin
: shrinking glyceride-type epoxy resin is composed of beamine or midamine and epoxy chloropropane containing two or more shrinking glyceride-based compounds. The
characteristics of this type of epoxy resin
are polyue, low viscosity, high activity, small epoxy equivalent, high cross-link density, high heat resistance, strong adhesion, strong force, good performance and corrosion resistance, can be mixed with other types of epoxy resin. Its
is
is a certain brittleness, molecular structure has epoxy and amine-based, so there is self-curing, storage period is short.
7, cyclo-oxide olefin compounds(1) Lipid cyclocyclic epoxy resins (epoxy cyclocarbon compounds) are low-molecular compounds containing two lipid epoxy-based. It is not a polymer in itself, but with the curing agent can produce a high performance of the three-dimensional body structure of the polymer.
ring epoxy resin is a low molecular compound, small viscosity, good process. Can be used as an active thinner. Epoxy equivalent is small, cross-link density is large, coupled with a good thermal stability of rigid lipid rings, so high heat resistance, but more brittle, poor toughness. Curing shrinkage is small and stretch strength is high. Because the synthesis process does not contain Cl, Na plasma, so the electrical performance is good, especially high temperature electrical performance and good arc resistance. Benzene ring-free, so it is resistant to ultraviolet light and weather.
(2) A fatty family cyclolyceride compound: it is an epoxy resin made from the double bond of adipose family olefins with peroxide cyclooxidation. There are no benzene rings, fat rings and hems in their molecular structure, only fat chains. Its performance characteristics:
a, for the line-type large molecules. At the same time, it has polybutylene rubber structure and epoxy resin structure, so it has good impact toughness and bonding properties.
b, similar to lipocyclic epoxy resins, is prone to reactions with
acidic curing agents
and less responsive to
pro-nuclear curing agents (amines)
.
c, resin molecules also contain double bonds and hydroxyl.
d, when acid-polyols are used as curing agents, and at the same time add styrene and peroxide triggers, can further increase cross-link density, thereby improving heat resistance and aesthetic properties.
e, mixed with curing agent after the viscosity is small, easy to operate, good process.
f, curing has good heat resistance, thermal deformation temperature of more than 200 degrees C, at high temperature has a very prominent strength hold rate. Bonding, weather resistance and electrical performance are excellent, and the electrical performance is stable at 200 degrees C.
g, the main
disadvantages
is the curing shrinkage rate is large.
8, hybrid and hybrid epoxy
(1) hexa-ring shrinking glycery epoxy resin: this is a class of high-performance epoxy resins containing hexa ring. Shrinking glycera is directly connected to the hybrid ring, resulting in excellent heat, weather and electrical properties. The main products are:
a, melamine epoxy resin (melamine triglyceride epoxy resin, TGIC): is melamine and epoxy chloropropane in the catalyst synthesis of a multi-function group epoxy resin with triglyceride hem. TGIC's reaction activity is higher than bisphenol A epoxy resin, poor solubility, so usually with acid anhydride as a curing agent, heating curing, it has excellent high temperature resistance, chemical stability, purple light aging and weather resistance. Good electrical and electrical properties, especially at high temperatures to maintain excellent electrical and electrical performance. The curing material
hard and brittle
, and has poor resistance to mechanical and thermal shocks.b, hyinem
epoxy resin
: Hyn epoxy resin is a new type of epoxy resin containing Hein ring (five-binary nitrogen hybrid ring). These resins can be shrinking glyceride-type, shrinking glyceline-type or shrinking glyceride-type resin, or can be single-haiin nuclear or multi-hein nuclear resin. It has the following characteristics: (1) low viscosity, good process. (2) Good thermal stability and high heat resistance. (3) Good weather resistance. Its coating is not prone to yellowing and powdering when exposed to sunlight or ultraviolet light. (4) In high voltage and ultra-high voltage under the performance of outstanding, especially with excellent arc resistance and leakage traces, can be used as high voltage insulation devices. (5) Polarity is very strong, low viscosity, so glass fiber, carbon fiber and a variety of fillers are very good wetting capacity and bondability, can not reduce the process without reducing the premise of adding a large number of fillers, so as to reduce the expansion coefficient and cost. (6) Less toxic. Can be used as food packaging and sanitary packaging coatings, non-toxic adhesives and so on. (7) Water-soluble hein epoxy resins can be used to treat textiles and paper to improve their strength and wrinkle resistance.
(2) hybrid epoxy resin: this is a type of epoxy resin that contains two different types of epoxy-based in its molecules. Therefore, it has the properties of both types of epoxy resins. Thus, in its curing performance and use performance has brought some single type of epoxy resin does not have the characteristics. For example, due to the different activity of the two types of epoxy-based, it is possible to achieve
-stage curing
, or to make b-order resins, or to achieve the requirements for low-temperature curing and high-temperature use. Greater flexibility in selecting curing agents. This provides more choice for formulation and process design, better meets process requirements and usage requirements, and expands the scope of use.