BIO-COMPOSITES OF HYDROXYAPATITE/CARBOXYMETHYL CELLULOSE/GELATIN AND HYDROXYAPATITE/CARBOXYMETHYL CELLULOSE/CHITOSAN/GELATIN WITH BONE LIKE LOAD BEARING PROPERTIES.
The present invention titled "Bio-composites of Hydroxyapatite/Carboxymethyl Cellulose/Gelatin & Hydroxyapatite/ Carboxymethyl cellulose/Gelatin/Chitosan with bone like load bearing properties", addresses in developing materials having load bearing properties similar to human bone in particular cancellous bone. The present work has four types of bio-composites prepared at lab level. The basic philosophy of preparation methodology is based on composition of natural human bone comprising Ca:P ratio of 1.6-1.67 and inorganic to organic matter in proportion of (60-70):(30-40) on weight basis with compressive strength between 0.22-10.44 MPa for cancellous bone and upto 190 MPa for cortical bone depending upon the type of loading (transverse or longitudinal). For this purpose the present invention utilized blending of inorganic phase with organic phase. The inorganic phase ranging between not less than 70% to not more than 80 % and remaining organic phase. The inorganic phase comprised of hydroxyapatite (HAp) and the organic phase comprised of combination of carboxymethyl cellulose (CMC) & gelatin and CMC, gelatin & chitosan respectively. In bio-composite samples CI and C2 the inorganic phase comprised of HAp powder blended with organic phase comprising of CMC & gelatin and CMC, gelatin & chitosan respectively. The bio-composite samples C3 and C4 are based on the methodology of blending of inorganic phase comprising of HAp slurry formed during the reaction of calcium oxide (CaO) and diammonium hydrogen phosphate (DAP) and organic phase comprising of CMC & gelatin and CMC, gelatin & chitosan respectively. The claim in the present invention regarding load bearing properties of bio-composite samples prepared are validated by conducting tests that include compressive, hardness and cutting strength test. The compressive strength of samples prepared have been observed between 2.35 to 65.71 MPa, hardness from 38.83 MPa to more than 156.05 MPa and cutting strength
