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The viscoelastic properties of the suspension of monodisperse spherical silica produced by hydrolysis of tetraethoxysilane in alcohol solvent with ammonia as a catalyst in polyethylene glycol (PEG) were studied. The results show that the SiO2/PEG suspension possesses the reversible shear thinning and shear thickening behaviors. In the shear thinning region, the loss modulus (G″) almost remains unchanged, whereas the storage modulus (G′) decreases. In the shear thickening region, G″ and G′ increase for the formation of the “clusters”. The larger G″ over G′ in all the stress studied shows that the system mainly possesses the viscous property, and that the energy dissipated(E d) is larger than that stored. E d of this suspension is proportional to the maximum strain (γ max) rising with the exponent of 1.92 under low shear stress; however, in the shear thickening region, E d is proportional to γ max rising with the exponent of 5.00.

Porous sol-gel glass of CaO-SiO2-P2O5 system with macropores larger than 100 μm was prepared by adding stearic acid as pore former when the sintering was carried out at 700 °C for 3 h. The sol-gel porous glass shows an amorphous structure. The diameter of the pore created by pore former varies from 100 to 300 μm, and macroporous glass has a narrow and small pore size distribution in mesoporous scale. The porosity and pore size of macroporous bioactive glass can be controlled.

Poly-L-lactide(PLLA) was synthesized by ring-opening polymerization from high purity L-lactide with tin octoate as initiator, and characterized by means of infrared, and 1H-nuclear magnetic resonance. The influences of initiator concentration, polymerization temperature and polymerization time on the viscosity average molecular mass of PLLA were investigated. The effects of different purification methods on the concentration of initiator and viscosity average molecular mass were also studied. PLLA with a viscosity average molecular mass of about 50.5×104 was obtained when polymerization was conducted for 24 h at 140 °C with the molar ratio of monomer to purification initator being 12 000. After purification, the concentration of tin octoate decreases; however, the effect of different purification methods on the viscosity average molecular mass of PLLA is different, and the obtained PLLA is a typical amorphous polymeric material. The crystallinity of PLLA decreases with the increase of viscosity average molecular mass.

The rheological behavior of fumed silica suspensions in polyethylene glycol(PEG) was studied at steady and oscillatory shear stress using AR 2000 stress controlled rheometer. The systems show reversible shear thickening behavior and the shear-thickening behavior can be explained by the clustering mechanism. The viscosity and the degree of shear-thickening of the systems strongly depend on the mass fraction of the silica, the molecular weigh of PEG and the frequency used in the rheological measurement. The silica volume fraction of the systems is 1.16%–3.62%, corresponding to the mass fraction of 4%–9%. The shear-thickening taking place in the low volume fraction may contribute to the fractal nature of the silica. At oscillatory shear stress, when the shear stress is less than the critical stress, the storage modulus decreases significantly, meanwhile the loss modulus and the complex viscosity almost remain unchanged; when the shear stress is larger than the critical stress, the storage modulus, the loss modulus and the complex viscosity increase with the increase of shear stress. The loss modulus is larger than the storage modulus in the range of stress studied and both moduli depend on frequency.

The biocompatibility evaluation of calcium phosphate based biomaterials is performed by tissue culture in vitro model. Three kinds of bioceramic materials which are potential to deal with bone trauma and/or conduct tissue growth are recommodated. The biological research results show that human and animal osteoblast cells anchor the materials surface in two hours in culture. Confocal laser scanning microscopy (CLSM) demonstrated the normal cell distribution and proliferation on both of dense and porous biomaterials. Hydroxyapatite and tricalcium phosphate stimulate cell proliferation. However, DNA and protein synthesis were considerably limited and the apoptosis phenomenon would be present on the hydroxyapatite (HA) materials by adding Al, Mg elements. Several important methods of biocompatibility evaluation of implant materials are described and the related biological molecular techniques such as tissue culture, cell transfection, cellular DNA stain, and Lowry assay are involved in the present research.