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Thermal and mechanical properties <strong>of</strong> poly (v<strong>in</strong>yl chloride)/ microscale<br />

and nanoscale calcium carbonate composites via melt <strong>in</strong>tercalation<br />

C. B. Patil, U. R. Kapadi, D. G. Hundiwale and P. P. Mahulikar*<br />

School <strong>of</strong> Chemical Sciences, North Maharashtra University,<br />

Jalgaon - 425 001 (M. S.) India<br />

Email: mahulikarpp@rediffmail.com , dghundiwale@yahoo.com<br />

________________________________________________________________________<br />

Abstract<br />

Calcium carbonate was synthesized by <strong>in</strong> situ deposition technique and its nano size (35<br />

to 60 nm) was confirmed by Transmission Electron Microscopy (TEM). Composites <strong>of</strong> the filler<br />

CaCO3 (micro and nano) and the matrix poly (v<strong>in</strong>yl chloride) (PVC) were prepared with different<br />

filler load<strong>in</strong>g (0-5 wt. %) by melt <strong>in</strong>tercalation. Brabender torque rheometer equipped with an<br />

<strong>in</strong>ternal mixer has been used for preparation <strong>of</strong> formulations for composites. The effect <strong>of</strong> filler<br />

content both nano and micro level on the nanostructure and properties is reported here. The<br />

nanostructures were studied by wide angle X-ray diffraction (WAXD). The mechanical, thermal<br />

and dynamic mechanical properties <strong>of</strong> PVC/ micro and nano CaCO3 composites were<br />

characterized us<strong>in</strong>g Universal Test<strong>in</strong>g Mach<strong>in</strong>e (UTM), Thermo Gravimetric Analyzer (TGA)<br />

and Dynamic Mechanical Analyzer (DMA). The results <strong>of</strong> thermal analysis <strong>in</strong>dicated that the<br />

thermal stability <strong>of</strong> PVC/nano-CaCO3 composites was improved as compared with correspond<strong>in</strong>g<br />

microcomposites and that <strong>of</strong> prist<strong>in</strong>e PVC and maximum improvement was obta<strong>in</strong>ed at 1 and 3<br />

phr load<strong>in</strong>gs. However, the tensile strength decreased significantly with <strong>in</strong>creas<strong>in</strong>g load<strong>in</strong>g <strong>of</strong><br />

both nano and micro CaCO3 while storage modulus and glass transition temperature <strong>in</strong>creased<br />

significantly.<br />

Keywords: Nanoparticles, Transmission Electron Microscopy (TEM), Wide Angle X-ray<br />

Diffraction (WAXD), Tensile strength, Thermal stability.<br />

________________________________________________________________________<br />

1. Introduction:<br />

Nanoscale calcium carbonate (nano CaCO3) is one <strong>of</strong> the most common spherical nanoscale<br />

fillers used <strong>in</strong> the preparation <strong>of</strong> nanocomposites. CaCO3 can be produced by a variety <strong>of</strong><br />

methods, <strong>in</strong>clud<strong>in</strong>g precipitation, dry gr<strong>in</strong>d<strong>in</strong>g, and wet gr<strong>in</strong>d<strong>in</strong>g. The basic grades <strong>of</strong> CaCO3 can<br />

be differentiated by changes <strong>in</strong> the size distribution, particle size, surface area, morphology,<br />

surface chemistry, and so forth [1-4].<br />

This nanoconcept has been mostly focused on thermoplastic and thermosett<strong>in</strong>g polymers<br />

<strong>in</strong>clud<strong>in</strong>g polyamides, polypropylene, epoxies and polyesters. The addition <strong>of</strong> nano-CaCO3 to

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