Development Of Epoxy Grout
Development of Epoxy Grout
The development of Epoxy Grout has gone through three stages:
First generation product is directly used emulsifier to emulsify, severe mechanical agitation, the obtained emulsion particles, so the emulsion particle size is larger, generally at about 5 microns, because there is a free emulsifiers in emulsion, curing in water, precipitation from coating paint film caused by poor water resistance, and because the grain size is coarse, film forming difficulties, thus restricted the application.
The second generation of Epoxy Grout is water soluble epoxy resin curing agent emulsified oil solubility and the characteristics of this kind of Epoxy Grout system is the use of curing agent are water-soluble when two components mixed curing, curing agent from the water phase diffusion into the resin particles, so the resin particle appearance match high curing agent concentration, make the appearance easy to solidify and form scale, to prevent resin particles form a film, eventually make coating uneven distribution of resin and curing agent and the influence of film performance, lead to the solubility parameter mismatch is also in the popularization of the second generation of Epoxy Grout system factor. The second generation of Epoxy Grout system of another kind of form is to put the made water dispersible emulsion, epoxy resin and curing agent for the system of water soluble solubility parameter mismatch problem also exists, because is hydrophobic and water-soluble epoxy resin curing agent has a strong hydrophilic, the mixture of two components due to the hydrophilic and hydrophobic there are great differences, which affect the paint film.
The third generation of Epoxy Grout system is in the 90 s by the Shell companies victory after years of research and development of the system of epoxy resin and curing agent is connected to the nonionic surface active agent, surfactant system does not exist to swim ion in appearance. After mixing the two components, the solubility parameters are similar, the compatibility is good, and the film can be obtained even after curing, which can meet or exceed the paint film performance indexes of solvent coatings. Due to the excellent physical and mechanical properties, electrical insulation, drug resistance and adhesive ability, can be used as coating, casting material, mold material, adhesive, laminated material in the form of direct or indirect use of permeate from daily necessities to all aspects of the national economy such as high-tech fields, such as: aircraft, spacecraft in composite materials, large scale integrated circuit packaging materials, generator insulation materials, steel and wood coatings, mechanical, civil construction adhesive and the lining of food cans and metal corrosion electrophoresis coating materials, etc., it has very broad application prospect.
The elongation of epoxy resin without modification is low, poor toughness and brittle. When subjected to internal stress or external stress, the defect area is rapidly formed and expanded into cracks, resulting in the cracking of the solidified substance. Modified epoxy resin curing material has great toughness and impact resistance. The toughening agent can be divided into two kinds: active and inactive.
The curing reaction of Epoxy Grout resin with active groups can also be mixed with epoxy resin. Toughening agent commonly used are: liquid polysulfide rubber, NBR (liquid end carboxyl nitrile rubber) end carboxy (hydroxyl) polybutadiene rubber, polyvinyl acetal, pu, nylon, low molecular polyamide and polyether resin and so on.