Comparative study on improvement in mechanical and flame retarding properties of epoxy-CaCO3 nano and commercial composites

Commercial and nano calcium carbonate (CaCO3) filled epoxy composites were processed at 2 to 10wt% compositions. Nano size CaCO3 was synthesized using in-situ deposition technique. Its nanosize and mixing with epoxy were confirmed by X-ray diffraction (XRD) method. X-ray diffractograms show that complete exfoliation occurs in the case of nanosize particles while micron size particles do not exfoliate. The effect of nanosize and commercial CaCO3 was studied on mechanical and flame retarding properties. The impact strength of composite increased up to 6wt% loading of nano filler and further decreased. Young's modulus was observed at 1400 Mpa and 1100 Mpa for nano and commercial CaCO3, respectively at their 10wt% loading, while pure epoxy showed 1000 Mpa; likewise, flame retarding properties improved six to four times on loading of nano and commercial CaCO3, respectively in comparison to pure epoxy resin. The improvement is due to exfoliation of nano in epoxy matrix, which is observed by X-ray diffractograms.