This material contains information on working with epoxy resins, which is totally different from the DIY jewelry findings, in the most typical area of application – the production of epoxy glue to impregnate the material with fiberglass for the manufacture and repair of various buildings (the boat, the elements of the car body, etc.) Or performing space waterproofing (floor and walls of basements, swimming pools), etc.
1) We strongly recommend you to choose the best for your purposes the ratio of transparent epoxy resin, hardener and plasticizer by making a small test samples. The reaction of the resin and hardener is irreversible, in case of error – resin will be spoiled.
2) The polymerization time (gelation gelation) – the time required for a given mass of epoxy resin to its treatment in the solid state and corresponds to the following rule: The polymerization time depends on the temperature of the mixture ratio and the area weight of the resin. For example, if 100 g of epoxy resin and hardener mixture PEPA treated in the solid state for 30-50 minutes at a starting temperature 22-24 ° C, at an initial temperature of 15 ° C it would take more than an hour. And if the same 22-24 ° C. 100 g of the epoxy resin and hardener mixture smudge on an area of 1 m², polymerization takes more than 2 hours.
3) The rate of polymerization of the epoxy resin mixed with hardener though depends on the initial temperature – polymerization mechanism itself does not depend on it. The reaction of epoxy resin and hardener is irreversible.
4) Unprotected Epoxy not tolerate sunlight (UV radiation). After about six months (time is rather arbitrary and depends on many factors), begins its turbidity, the destruction of a partial loss of its physical properties. Therefore the finished product must be protected with the help of paints, varnishes, etc. containing UV protection.
5) Epoxy resins during curing can form on its surface a thin, tacky film. It is formed in the presence of carbon dioxide and water vapor, especially in cold, wet weather. This film is water-soluble and must be removed mechanically before sanding or painting.
6) To the finished product was plastic, it did not break, do not crack over time in the epoxy resin is necessary to add a plasticizer. The plasticizer is required to be used when manufacturing products sufficiently large as possible cracking further solidification step.