Flexible inorganic films and coatings

This paper describes a new family of materials derived from layer minerals such as phillosilicates and includes vermiculite, montmorillonite, etc. They are structurally analogous to the organic crystalline polyethylene in which the crystalline lamellae are replaced by inorganic lamellae of comparable dimensions. Flexible films can be produced with tensile strengths of 30 to 160 MN m^–2, elongation of up to 6% and moduli of 14 G N m^–2; they are stronger than organic films. Suspension of discrete lamellae in water can be used as coating for a variety of surfaces. The most interesting is the vermiculite-coated glass fibre which has unique properties. Finally, the suspension can be used to make a wholly inorganic foam which has similar properties to organic foams with good compressive strength.