7 сентября, 2015 
Pokraskin Epoxy resin-based RHMs are also applied as a melt, but they solidify to build a thermosetting polymer network that cannot be re-melted (see Section 5.5). Compared to thermoplastic hot melts, they have a higher inner strength and are used primarily in car manufacture.
These adhesives are delivered as one-part reactive pre-polymer systems with a long pot life. Curing at room temperature is prevented by a catalytic system that is only effective at higher temperatures, or by a second reactive amine component that is also only reactive at higher temperatures. Immediately before processing, epoxy-based RHMs are melted in the quantity needed and then applied at temperatures ranging between 60 and 80 °C; assembly may be handled during the solidification. The final strength is obtained (e. g. in car manufacture) in the stoves where the body undercoat and paint system are dried [17].
Depending on the nucleophilic characteristics of the functional groups (-NH2 > — NH > — OH), the polyaddition reactions (which are used to generate epoxy resin-
based systems) proceed at different rates. For example, at a molar ratio of 1: 2, the cold-setting reaction of secondary diamines with bifunctional epoxides makes it possible to generate thermoplastic, meltable alkanolamine polymer compounds. At room temperature, further reaction is not expected to take place owing to the low reactivity of the hydroxyl groups. With increasing temperatures, however, these hydroxyl groups react further with the remaining epoxide groups in the form of an additional crosslinking effect, resulting in a polymer structure that is no longer meltable [18].
5.3.7
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