Abstract
Synopsis: Phenolic/organo-montmorillonite nanocomposites were prepared from phenol novolac, hexamethylenetetramine and montmorillonite (MMT) organized with phosphonium salt such as triphenylstearyl (PhStP), tris(hydroxyphenyl)undecanoic acid (HOPhUP), and trisdiphenyl ether undecanoic acid (PhOPhUP) by hot-roll kneading. Structure and properties of those nanocomposites were investigated. It was found that phenolic resin was intercalated between layers of these organomontmorillonite. The degree of dispersion of MMT in phenolic/PhStP－MMT nanocomposite was the best. On the other hand, there was some aggregation of MMT about 1μm diameter in phenolic/PhOPhUP－MMT nanocomposite. The mechanical strength of these composites was comparable to or tended to decrease with phenolic resin alone. However, heat resistance, low thermal expansion, and flame retardant of these composites were better than those of phenolic resin alone or phenolic/MMT organized with oleylbis(hydroxyethyl)methylammonium salt used as reference. In particular, phenolic/HOPhUP－MMT nanocomposite showed good heat resistance and flame retardant.
