| In order to improve the traditional preparation methods of polymer inorganic nanocomposite and improve the performance of the nanocomposites, in-situ precipitation polymerization has been taken in supercritical carbon dioxide(scCO2) for Poly(2-hydroxyethylmethacrylate)/hydroxyapatite nanocomposites and PNIPAm/MCF nanocomposites. Sodium alginate/bentonite composite aerogel using supercritical fluid drying were prepared successfully. The research works are as follows:1. 2-hydroxyethylmethacrylate as monomer, nano size hydroxyapatite as inorganics, scCO2 as solvent, PHEMA/nHAP nanocomposites were synthesized via in situ precipitation polymerization with 94% yield. The composites is consists of nucleus of nHAP and shell of PHEMA and the particle size of 30 wt.% nHAP composites in the range of 25-85 nm. The mechanical properties of the PHEMA/nHAP nanocomposites were better than those of PHEMA, and the compressive modulus and strength of composites with 30 wt.% nHAP were 193 and 29 MPa, respectively. The adsorption behaviors of the nanocomposites toward bovine serum albumin were evaluated, and results indicated that the adsorption amount of the analyte can reach as high as 282 mg/g.2. Sodium alginate/ bentonite aerogel were prepared by supercritical fluid drying method. The aerogel with specific surface area of 443.55 m2/g, density of 0.0596 g/cm3 and pore volume of 3.617 cm3/g. Through fixation and intercalation effects bentonite uniformly dispersed in sodium alginate matrix. The adsorption amount of the lysozyme can reach as high as 697 mg/g when the concentration of lysozyme is 1.2g/L under pH 8.3. Temperature sensitive composites were synthesized in scCO2 by two-step method. Firstly, modified MCF were filled with N-isopropylacrylamide, AIBN, acrylic, then in-situ polumerization proceeded in the pore of MCF. The grafting ratio and drug loading capacity can reach 65.2% and 12.3%, respectively. PNIPAm-AA/MCF/5-fu shows thermal-sensitivity and pH- sensitivity. |
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