| In attempt to prepare and study the materials of artificial bone, the fine bioactive hydroxyapatite (HA), which can be combined close with collagen and cells, was selected as the inorganic phase; the excellent biocompatible and biodegradable polylactic acid was chosen as the organic phase, then, applied the treated CT data to the rapid prototyping (RP) technology, and the two phases were composed into ideal replace material for artificial bone. In this paper, the method and process of the chemo-synthesis, the identification and determination of the productions were studied; the preparation of data before rapid prototyping, the theory of fused deposition modeling (FDM) technology and selected laser sintering (SLS) technology, the preparation for silk threads and powders used to FDM and SLS respectively, were also explained in detail. The main conclusions were obtained as follows:(1) Via indirect way, PLA was succeeded in synthesizing. First, lactic acid was polymerized into PLA with low molecular weight, which was decomposed to ringy dimer - lactide at high temperature and in high vacuum. After separating and purifying the coarse lactide, obtained high molecular weight PLA by ring-opening polymerization with the help of the catalyzer Sn(oct) 2. The highest Mn of PLA we synthesized was 8612 g/mol.(2) By means of DSC melting point, IR and elements analysis, the monomer of ring-opening polymerization was proved to be lactide, whose melting point was 122.69, close to the theoretic value 125; and the contents of C, H, O was 49.63%, 5.55%, 44.82% respectively, while their theoretic values were 50.00%, 5.56%, 44.44% respectively.(3) Applied the way of orthogonal design, studied mainly four influence factors on the molecular weight of PLA, namely, catalyzer's dosage, temperature, vacuum value, time. The results indicates that, under the condition of four influence diathesises and three levels of each, the average extremum difference molecular weight of PLA were 2627 g/mol, 1831 g/mol, 594 g/mol, 2254 g/mol respectively, i.e., catalyzer's dosage was most influential, with time, temperature and vacuum value following. The analysis lead to the best polymerization condition as follow: catalyzer's dosage was 0.2%, temperature was 145, vacuum value was 0.08Mpa, and time was 3 hours.(4) Obtained the CT data by scanning the bone faultage section, then the Pro/E software established the artificial bone's surface and three-dimensional structure inside. And dealed with approximately the artificial bone's curvisurface before rapid process, i.e., a set of little triangles were neared to free the curvisureface. Slices were treated at intervals to pick-up the section profiles, along the direction of processing the three-dimensional model.(5) The silk thread materials of ABS and PP were prepared, by FDM, the process temperature of ABS was set at 230, and PP's was 220 correspondingly. Then, grinded the home-made PLA into powders, combined with HA powders in ratio of necessitity, to obtain the PLA/HA composite powders served as the materials of artificial bone for SLS.
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