Preparation of hydroxyapatite/poly(vinyl alcohol) composite film with uniformly dispersed hydroxyapatite particles using citric acid

Abstract

Biocompatible hydroxyapatite (HA)/poly-(vinyl alcohol) (PVA) composites and their transparent films were prepared by the coprecipitation and solvent casting method. The formation of HA in PVA composite powder was confirmed by the characteristic phosphate bands at 1100-1032 and 565 cm À1 at FT-IR spectra, and the weight ratio of HA to PVA was 50/50 examined by TGA. The crystal melting temperature of HA/PVA decreased compared with that of pure PVA. HA/PVA (50/50) composite powder and pure PVA were dissolved in dimethyl sulfoxide to obtain a film with HA/PVA weight ratio of 10/90. To improve HA particles' dispersity, which is one of the major factors affecting the mechanical properties of composite materials, various contents of citric acid were used for the preparation of HA/PVA films. At a citric acid concentration of 5 wt %, HA/PVA film with good dispersity of HA particles was obtained.

Effect of γ-Fe2O3 Nanoparticles on the Cross-Linking and Final Properties of PVA/Citric Acid-Based Nanocomposites

“…This biocompatible natural organic acid with a multicarboxylic structure, apart from improved mechanical properties, thermal stability, or reduction of moisture sensitivity, endows its applicability in food packing or biomedicine. , Moreover, CA could also play an important role as a surfactant for improving the dispersion of inorganic nanoparticles in organic–inorganic nanocomposites. In fact, it has been used as a dispersant to prepare nanocomposites based on a PVA matrix with different fillers as ZnAl, Al 2 O 3 , or hydroxyapatite, resulting in composites with proper nanofiller distribution. − …”

Encapsulation of Venlafaxine HCL in to Poly-E-Caprolactone Microspheres by W/O/W Amd W/O/O Emulsion Solvent Evaporation Technique and Comparison for Its Controlled Release Properties.

“…This revealed the presence of drug with no interaction which proved its compatibility. The DSC thermogram of Venlafaxine alone showed a sharp endothermic peak at 215.03°C with a heat of fusion of 124.42 J/g which is similar to its standard value (Chung et al, 2007). While the DSC thermogram of Drug+PVA+PCL showed three distinguished peaks of their own.…”

Fabrication and characterization of a starch-based nanocomposite scaffold with highly porous and gradient structure for bone tissue engineering

“…To break apart the as-received HA nanoparticle agglomerates, 30 pph HA nanoparticle was mixed with 5 pph citric acid and some deionized water, then the obtained suspension was ultra-sonicated three times for 10 min. Here, citric acid was employed to neutralize the surface charge of the HA nanoparticles, and thus to help with the dispersity of the nanoparticles in water [32]. Afterwards, the ultra-sonicated suspension was added to the ultimate suspension in sections 2.2.2, and then mechanically stirred at 1500 rpm and 90 °C for 30 min.…”