Mixing

Improper mixing of resinous materials can lead to serious problems. This improper mixing can be in several forms. Some of these are:

1. Mix Ratio Error: If the ratio of Part A to Part B is NOT proper the cross link density will not be at its optimum. This will result in soft cures, loss of physical properties, lack of chemical resistance, discoloration and disbonding. This could be the result from either too much Parts A or B.

2. Improper Blending: The ratio of Part A to Part B may be proper but if the two are NOT thoroughly and completely mixed, the cure will not be complete. This is primarily the result of not enough mixing time or the wrong equipment used to mix Part A and Part B. The effect is localized areas on the floor with too much Part A or too much Part B. Part B side is an excellent wetting agent and if added first will wet out aggregate and make complete mixing impossible. In cases where the viscosity of Part A is significantly different fro Part B additional caution must be taken to insure proper mixing from material on the sides of the pail. For this reason, it is never a good idea to turn the mixing pail over for drainage after emptying the mixed epoxy onto the floor. The final consequences are as above and results in premature failure.

3. Failure to Premix the Individual Components: If the Part A is a pigmented material, typically this side is premixed. However, if less than full containers are to be used each side should be premixed before combining. Epoxy formulations, even in clear, contain several ingredients. During shipping and storage, separation of these ingredients may occur especially in colder temperatures. If partial containers are used the formulation is not complete and problems such as craters, fisheyes, bubbles, color separation, tacky surfaces and other surface defects will be seen. The proper mixing procedure is a low speed drill and a Jiffy blade. The material should be mixed with the blade under the level of the mix liquid for a minimum of three minutes.