The effect of acetalation on the tensile properties of attapulgite-phenolphthalein poly(ether ether ketone) composites

Composites of phenolphthalein poly(ether ether ketone) (PEK-C) with a naturally occurring clay, attapulgite, have been prepared. The tensile behaviour of the composites has been studied. To improve adhesion between PEK-C and attapulgite in the composites, acetalation of attapulgite was carried out by chemical reaction with butyraldehyde and benzaldehyde. It was found that acetalation of attapulgite can enhance the Young's modulus, tensile strength and elongation at break of the composites. Acetalation with benzaldehyde was more effective in improving the tensile properties of the composites. Morphology observations by scanning electron microscopy showed that the interfacial adhesion between PEK-C matrix and the attapulgite acetalated with benzaldehyde is excellent. This was considered to be due to the better compatibility of the benzaldehyde acetals on the surface of attapulgite particle with PEK-C resin. © 1990.