It is well known that various polyamine compounds are widely used as raw materials for hardening agents of epoxy resins or as components of polyamide resins. In these compounds, typical examples of the polyamine compounds are aliphatic amines such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, hexamethylenediamine, etc.; aromatic amines such as phenylenediamine, diaminophenylmethane, diaminophenylsulfone, etc.; aliphatic amines having aromatic ring, such as xylylenediamine, etc.; and alicyclic amines such as bisaminomethylcyclohexane, isophoronediamine, etc. These polyamine compounds each has the reactivity of the amino group as the specific feature caused by the active hydrogen and are used for various purposes. Further, polyamine compounds which have been modified in a manner suitable for the specific polyamine compound have been widely used and, for example, the modified compounds are used as hardening agents for epoxy resins. In particular, xylylenediamine such as m-xylylenediamine has a property specific to aliphatic diamines having an aromatic ring and is used as a main raw material for polyamide or a main raw material for a hardening agent for epoxy resin. Furthermore, a modified compound obtained by reacting the above compound with phenol and formaldehyde, or with methyl methacrylate, acrylonitrile or an epoxy compound is widely used as an epoxy resin itself or a hardening agent for epoxy resins. It is known that, when the above modified compound is used as a hardening agent for epoxy resins, the low-temperature hardening property of the epoxy resin is greatly improved and the hardened product of the epoxy resin shows excellent chemical resistance and excellent gloss and appearance. However, the hardening agent and the hardened product show a whitening phenomenon caused by the absorption of carbon dioxide in the atmosphere and the hardened product has problems that the product is hard and has no flexibility as well as is inferior in adhesion and impact resistance.
However, for further increasing the acceptable range of modification of m-xylylenediamine so as to meet a wide variety of use, it has been desired to convert m-xylylenediamine into more polyfunctional polyamine compounds without adversely affecting the characteristics of m-xylylenediamine.
USPTO Backgrounds
USPTO Backgrounds