Epoxy resin can be effectively used in a vast number of molding process. It has the ability to cure at very low temperatures and compared to other materials epoxy resin has been frequently used in combination with an open mold. Open molding processes which often utilizes the use of epoxy include resin transfer molding and filament winding. Even though it is also possible to use epoxy in closed mold injection molding. Unlike polyeurethane or polyester, epoxy cures through the addition of hardener which then turns it into a liquid epoxide. The two components are then stored separately before being mixed and cured during the whole molding process. While there are different varieties of epoxides and hardeners which can be used to create epoxy resin, the most common and frequently used components are the epoxide epichlorohydrin and the hardening amine triethylenetetramine, commonly used by romeo rim. As the reaction that produces the epoxy resin is an addition reaction, both of the components has an active role in it. It is very important to carefully control the ratio of the epoxide and the hardener that is used. If there is an incorrect ratio, the results in bits of uncured hardener remaining in the finished product will weaken the finished part as well as destroying the aesthetic appeal and feel to it. Epoxy can also be combined with a reinforcing fiber to produce fiber reinforced plastic which is a strong material with a variety of uses. While molding with epoxy, either the hand lay up process, which means placing the fibers in the mold by hand; or the spray up, which means spraying the fibers into the mold with a pneumatic gun, can be used.
While any of the common fiber reinforcements, such as, glass, carbon, aramid and basalt can be used in conjunction with epoxy resin, glass is most frequently chosen due to its high stiffness which complements the natural stiffness and the strength of epoxy. A glass and epoxy FRP composite is very tough and durable when compared to similar reinforced plastic materials.
Epoxy resin moldings has a lot of benefits.
- Top notch adhesion: The main advantage of epoxy which basically differentiates it from other thermostat polymers, is its ability of excellent cohesion. The adhesion of epoxy resin has led to its wide and varied use in the manufacture of paints, sealants, varnish, casting compounds, caulking compounds and glues. Epoxy based adhesives are widely used in high performance industries including aerospace and watercrafts.
- Durable and Strong: Epoxy resin is very strong, stiff and tough and is very resistant to extreme heat, extreme cold, electricity and a wide variety of chemicals. It can withhold a good dimensional stability and fatigue, even over time and exposure to different elements. It has more viscosity than other similar materials, which features and average viscosity of 900 centipoise. These marvelous mechanical properties can be reinforced fibers, mostly glass.
- Cost effective: Though epoxy is slightly more costly its low cure temperature saves on materials needed for the mold manufacturing.