What are the uses of epoxy resins?
1. Kinds of curing agent:The common epoxy resin curing agents are aliphatic amines, alicyclic amines, aromatic amines, polyamides, anhydrides, resins, tertiary amines, and in addition, UV or light can solidify the epoxy resin under the action of photoinitiator. Curing agent at normal or low temperature is usually amine curing agent, and curing and curing are commonly used.2, the dosage of curing agent(1) when amines are used as crosslinking agents, they are calculated by pressing:Amine dosage =MG/HnIn style:M= amine molecular weightHn= contains the number of active hydrogenG= epoxy value (epoxy equivalent per 100 grams of epoxy resin)The range of change is no more than 10-20%. If the amine is cured, it will make the resin brittle. If the dosage is too little, the curing is not perfect.(2) calculate by the type of anhydride class:The amount of anhydride is =MG (0.6~1) /100:M= anhydride molecular weightG= epoxy value (0.6~1) was used as the experimental coefficient3, choose the principle of curing agent: curing agent on the performance of epoxy resin greater impact, generally in accordance with the following selection.(1) choose from the performance requirements: some require high temperature resistance, some require good flexibility, and some require good corrosion resistance. According to different requirements, the appropriate curing agent should be used.(2) choose from the curing method: some products can not be heated, then the thermal curing agent can not be used.(3) choose from the applicable period: the so-called "applicable period" refers to the time when the epoxy resin is added to the curing agent until it can not be used. For the long term, anhydride or latent curing agent is usually used.(4) from the safety of choice: General requirements, small toxicity is good, easy to safe production.(5) choose from the cost.
1, from the use of choiceAs the adhesive is the best selection of middle value of epoxy (0.25-0.45) resin, such as 6101, 634; make the best choice when casting high value of epoxy resin (>0.40), such as 618, 6101; the general selection for coating with low value of epoxy resin (<0.25), such as 601, 604, 607, 609 etc..2, choose from the mechanical strengthThe resin with higher epoxy value is larger, but more brittle; the epoxy value is moderate, the strength is good when the temperature is high and low; the epoxy value is lower, but the strength is worse at high temperature. Because of the strength and the degree of cross-linking, the epoxy value is high, the degree of crosslinking is high after curing, the epoxy value is low, and the crosslinking degree is low after curing, so the difference in strength is caused.3, from the operation requirementsWithout high temperature, not to the required strength, hope to epoxy resin quick drying, not easy to lose, can choose the epoxy value lower resins; if the permeability is good, strength, can choose epoxy value higher resin.
Epoxy resins are commonly used in conjunction with additives in order to obtain practical value. Additives can be selected according to different uses, commonly used additives have the following categories: (1) curing agent; (2) modifier; (3) filling; (4) diluent; (5) other.Among them, curing agent is an indispensable additive, whether it is used as adhesive, coating, pouring material, need to add curing agent, otherwise, epoxy resin can not be cured.
