| Polyether-ether-ketone(Polyether-ether-Ketone,PEEK)is an aromatic thermoplastic polymer consisting of 2 ether bonds and 1 ketone bond.The benzene ring has excellent structural stability,mechanical properties,biological properties,as a kind of semi-crystalline polymer,which is known as the most potential high-performance special engineering plastics to replace metal materials.It is used in automobile manufacturing,biomedicine,food processing,aerospace,electronic appliances and other fields.Considering the development status of fused deposition modeling additive manufacturing technology and the application potential of polyether-ether-ketone in biomedical field,this paper takes the research on the additive manufacturing technology of PEEK and the biological application of biomaterial modified PEEK composite as the main line.By regulating the temperature process of PEEK additive manufacturing,the comprehensive post-processing method of printed PEEK parts is explored.To carry out the practical application of chemical modified PEEK of biological materials in the biomedical field,so as to improve the mechanical properties of printed parts,optimize the bioinerty of materials and improve the biological activity,and realize the controllable rapid prototype manufacturing of PEEK with comprehensive enhancement of mechanical,chemical and biological properties.In this paper,the control technology and mechanism of printing parameter ambient temperature and printing substrate temperature on mechanical properties and crystallinity of PEEK are studied.The influences of the temperature of the printing chamber and the temperature of the printing substrate on the interlayer morphology,interlayer bonding force,mechanical properties(bending and tensile strength),dynamic mechanical properties and crystallinity of the printing samples with thin thickness were quantitatively analyzed.The maximum tensile strength was 86.62 MPa and the maximum bending strength was 113.21 MPa.When the ambient temperature was 90 ℃ and the substrate temperature was 160 ℃,the best mechanical properties of the printed PEEK sample is obtained,and the interlaminar binding quality,tensile strength,bending strength and crystallinity are effectively improved.The coupling effect of substrate and ambient temperature in the printing process significantly improves the strength and crystallinity of the printing interface,greatly reduces the internal pores and defects caused by printing process,and achieves the purpose of improving the mechanical properties.The influence mechanism and process route of different post-processing processes on mechanical performance improvement of PEEK printout are studied.The changes of mechanical properties,crystallinity,energy loss and internal pores of the samples are explored through ultrasonic-assisted reinforcement process,annealing process and a variety of post-treatment processes combining the two kinds of processes.The results show that the composite process of ultrasonic-assisted reinforcement followed by annealing treatment was the best post-treatment process route,and the tensile strength and crystallinity are significantly improved.The porosity is greatly reduced.The maximum tensile strength was increased by 7.5%,the crystallinity was increased by 2.4%,and the porosity was increased by 65.6%.The feasibility of the comprehensive post-treatment technology combines with ultrasonic-assisted reinforcement and annealing process is demonstrated,and the regulation of mechanical properties of printing parts by multiple post-treatment technology is realized.The chemical synthesis method and biological characteristics of PEEK printed bone scaffold modified with bioactive glass surface are studied by using the experimental results of the previous process study,and its biological characteristics are analyzed.By comprehensively regulating the concentration of concentrated acid and reaction time,a process flow of structure process design-additive manufacturing-biomaterials surface modification-biological performance detection was established.The mechanical properties,hydrophilicity,toxicity,microscopic morphology,element composition and distribution,Fourier transform infrared spectroscopy,osteoblast proliferation and gene expression of the modified bone scaffold are tested.The rapid manufacture of PEEK bone scaffold with excellent biological characteristics is realized.The poor cell proliferation of PEEK material is greatly improved,which provides theoretical and experimental basis for clinical bone restoration.The repair of bone defects in animals with PEEK bone scaffold modified with bioactive glass surface is studied.The accuracy of the in-vitro biological characteristics study is verified by animal experiments,the tibial defect model of the hind leg of the rabbit is established,and the modified bone scaffold is implanted.It is found that the modified bone scaffold has both the elastic modulus and excellent biological activity similar to the natural bones,and plays the role of structural support and bridging in the defect,which effectively improves the poor biological characteristics of PEEK,provides a favorable growth environment for osteoblast differentiation,and has a good effect on the regeneration,repair and bone integration of large area of bone defect.During the process of PEEK fused deposition,the control of ambient temperature is the key parameter affecting the bonding quality,crystallinity and mechanical properties.The multi-postprocessing technology which combines ultrasonic-assisted reinforcement and annealing heat treatment can effectively eliminate the internal defects,improve the proportion of crystal phase and enhance the mechanical properties.And the fused deposition additive manufacturing technology can realize the actual applications of personalized and customized bone repair.Combined with the surface modification of bioactive glass,the biological activity of additive manufacturing PEEK is significantly improved,which has great application potential in the biomedical field. |
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