Mica schist particulates for composites

Abstract

Although mica is being used extensively for polymer j composites, the low-grade mica schist has never been 4 tried [1, 2]. Mica schist occurs in many parts of the world and in large quantities in Madhya Pradesh 0.96State, India. It is observed that because of their highly flaky nature, mica sheets are difficult to grind or cut. On the other hand, mica schist can be ground and incorporated into polymer or aluminium metal 0,72 composites. The present letter reports the use of mica schist particulates in polymers, namely epoxy composites. An ultrasonic vibration technique has been used for ~ 0~8 the delamination of the mica schist flakes [3]. The mica ~ I schist was collected from Jhabua district of Madhya Pradesh, India. It was ground, sieved and then water < elutriated before subjecting it to ultrasonic vibration. 0.24 The aspect ratio of the flakes was measured before and after ultrasonic vibration and though less than the I J aspect ratio of high-grade mica, the aspect ratio values 000] were tbund to increase by two to three times. Kaujjman et al. [4] have carried out extensive work on mica-polymer composites, but in most of their work and other work, mica having an aspect ratio of more than 50 to 100 has been used. The reason is, of course, obvious from the bonding point of view. As low-grade mica occurring in many parts of the world will have aspect ratio less than 50 to 100, it is worth studying their reinforcing properties with polymers. The present mica taken for study is a schist mica. However, the microscopic, X-ray diffraction, infrared and thermal studies indicate that this has all the properties of a clay mineral. The layering structure of this mica is clearly exhibited in the scanning electron d (nm) micrograph (Fig. 1). The infrared spectrum also indi-