- Engineering Research Center in Biomaterials, Sichuan University, Chengdu, Sichuan 610064, P. R. China;
With high thermal stability, excellent mechanical properties, suitable biocompatibility and radiolucency, polyaryletherketones (PAEKs) have been widely used in biomedical field such as trauma, spinal implants, craniomaxillofacial repair and so on. However, PAEKs are bio-inert in nature and often show weak osteointegration with host bone, limiting their further utilization in biomedical application. Therefore, how to improve the bioactivity and osteointegration of PAEK implants has become the focus in biomedical field. This paper reviews the current research advance and some existed problems in bioactive PAEKs, and outlooks the possible solution.
Citation: YUAN Bo, CHENG Qinwen, ZHU Xiangdong, ZHANG Kai, ZHANG Xingdong. Research advance in polyaryletherketones for biomedical applications. West China Medical Journal, 2018, 33(9): 1053-1060. doi: 10.7507/1002-0179.201808064 Copy
1. | Attwood TE, Dawson PC, Freeman JL, et al. Synthesis and properties of polyaryletherketones. Polymer, 1981, 22(8): 1096-1103. |
2. | Kurtz SM, Devine JN. PEEK biomaterials in trauma, orthopedic, and spinal implants. Biomaterials, 2007, 28(32): 4845-4869. |
3. | Fuhrmann G, Steiner M, Freitag-Wolf S, et al. Resin bonding to three types of polyaryletherketones (PAEKs)-durability and influence of surface conditioning. Dent Mater, 2014, 30(3): 357-363. |
4. | Kersten RF, van Gaalen SM, de Gast A, et al. Polyetheretherketone (PEEK) cages in cervical applications: a systematic review. Spine J, 2015, 15(6): 1446-1460. |
5. | Abdullah MR, Goharian A, Kadir MR, et al. Biomechanical and bioactivity concepts of polyetheretherketone composites for use in orthopedic implantsa review. J Biomed Mater Res A, 2015, 103(11): 3689-3702. |
6. | Moore R, Beredjiklian P, Rhoad R, et al. A comparison of the inflammatory potential of particulates derived from two composite materials. J Biomed Mater Res, 1997, 34(2): 137-147. |
7. | Mcgrail PT. Polyaromatics. Polym Int, 1996, 41(2): 103-121. |
8. | Converse GL, Conrad TL, Roeder RK. Mechanical properties of hydroxyapadite whisker reinforced polyetherketoneketone composite scaffolds. J Mech Behav Biomed Mater, 2009, 2(6): 627-635. |
9. | Yuan B, Chen YM, Lin H, et al. Processing and properties of bioactive surface-porous PEKK. ACS Biomater Sci Eng, 2016, 2(6): 977-986. |
10. | Yuan B, Cheng Q, Zhao R, et al. Comparison of osteointegration property between PEKK and PEEK: effects of surface structure and chemistry. Biomaterials, 2018, 170: 116-126. |
11. | Koehler S, Raslan F, Stetter C, et al. Autologous bone graft versus PEKK cage for vertebral replacement after 1-or 2-level anterior median corpectomy. J Neurosurg Spine, 2015, 13: 1-6. |
12. | Adamzyk C, Kachel P, Hoss M, et al. Bone tissue engineering using polyetherketoneketone scaffolds combined with autologous mesenchymal stem cells in a sheep calvarial defect model. J Craniomaxillofac Surg, 2016, 44(8): 985-994. |
13. | Deng Y, Liu X, Xu A, et al. Effect of surface roughness on osteogenesis in vitro and osseointegration in vivo of carbon fiber-reinforced polyetheretherketone-nanohydroxyapatite composite. Int J Nanomedicine, 2015, 10: 1425-1447. |
14. | Esposito M, Hirsch JM, Lekholm U, et al. Biological factors contributing to failures of osseointegrated oral implants. (Ⅱ). Etiopathogenesis. Eur J Oral Sci, 1998, 106(3): 721-764. |
15. | Togawa D, Bauer TW, Lieberman IH, et al. Lumbar intervertebral body fusion cages: histological evaluation of clinically failed cages retrieved from humans. J Bone and Joint Surg Am, 2004, 86A(1): 70-79. |
16. | Hahn H, Palich W. Preliminary evaluation of porous metal surfaced titanium for orthopedic implants. J Biomed Mater Res, 1970, 4(4): 571-577. |
17. | Sun L, Berndt CC, Gross KA, et al. Material fundamentals and clinical performance of plasma-sprayed hydroxyapatite coatings: a review. J Biomed Mater Res, 2001, 58(5): 570-592. |
18. | Hahn BD, Park DS, Choi JJ, et al. Osteoconductive hydroxyapatite coated PEEK for spinal fusion surgery. Appl Surf Sci, 2013, 283: 6-11. |
19. | Walsh WR, Bertollo N, Christou C, et al. Plasma-sprayed titanium coating to polyetheretherketone improves the bone-implant interface. Spine J, 2015, 15(5): 1041-1049. |
20. | Han CM, Jang TS, Kim HE, et al. Creation of nanoporous TiO2 surface onto polyetheretherketone for effective immobilization and delivery of bone morphogenetic protein. J Biomed Mater Res A, 2014, 102(3): 793-800. |
21. | Huang JX, Wan SH, Wang LP, et al. Tribological properties of Si-doped graphite-like amorphous carbon film of PEEK rubbing with different counterparts in SBF medium. Tribol Lett, 2015, 57(1): 1-9. |
22. | Ouyang L, Deng Y, Yang L, et al. Graphene-oxide-decorated microporous polyetheretherketone with superior antibacterial capability and in vitro osteogenesis for orthopedic implant. Macromol Biosci, 2018, 18(6): e1800036. |
23. | Suska F, Omar O, Emanuelsson L, et al. Enhancement of CRF-PEEK osseointegration by plasma-sprayed hydroxyapatite: a rabbit model. J Biomater Appl, 2014, 29(2): 234-242. |
24. | Lee JH, Jang HL, Lee KM, et al. In vitro and in vivo evaluation of the bioactivity of hydroxyapatite-coated polyetheretherketone biocomposites created by cold spray technology. Acta Biomater, 2013, 9(4): 6177-6187. |
25. | Wen J, Lu T, Wang X, et al. In vitro and in vivo evaluation of silicate-coated polyetheretherketone fabricated by electron beam evaporation. ACS Appl Mater Interfaces, 2016, 8(21): 13197-13206. |
26. | Shimizu T, Fujibayashi S, Yamaguchi S, et al. Bioactivity of sol-gel-derived TiO2 coating on polyetheretherketone: in vitro and in vivo studies. Acta Biomater, 2016, 35: 305-317. |
27. | Chen M, Ouyang L, Lu T, et al. Enhanced bioactivity and bacteriostasis of surface fluorinated polyetheretherketone. ACS Appl Mater Interfaces, 2017, 9(20): 16824-16833. |
28. | Liu X, Gan K, Liu H, et al. Antibacterial properties of nano-silver coated PEEK prepared through magnetron sputtering. Dent Mater, 2017, 33(9): e348-e360. |
29. | Gümüş S, Polat Ş, Waldhauser W, et al. Biodegradation of anti-microbial titanium-magnesium-silver coatings on polyetheretherketone for bone-contact applications. Surf Coat Tech, 2017, 320: 503-511. |
30. | Deng Y, Yang L, Huang X, et al. Dual Ag/ZnO-decorated micro-/nanoporous sulfonated polyetheretherketone with superior antibacterial capability and biocompatibility via layer-by-layer self-assembly strategy. Macromol Biosci, 2018, 18(7): e1800028. |
31. | Ouyang L, Qi MY, Wang SN, et al. Osteogenesis and antibacterial activity of graphene oxide and dexamethasone coatings on porous polyetheretherketone via polydopamine-assisted chemistry. Coatings, 2018, 8(6): 203. |
32. | Hiruta T, Yabutsuka T, Watanabe S, et al. Apatite formation ability of bioactive bearing grade polyetheretherketone fabricated by incorporation of apatite nuclei. Key Eng Mater, 2017, 758: 69-74. |
33. | Ha SW, Kirch M, Birchler F, et al. Surface activation of polyetheretherketone (PEEK) and formation of calcium phosphate coatings by precipitation. J Mater Sci Mater Med, 1997, 8(11): 683-690. |
34. | Waser-Althaus J, Salamon A, Waser M, et al. Differentiation of human mesenchymal stem cells on plasma-treated polyetheretherketone. J Mater Sci Mater Med, 2014, 25(2): 515-525. |
35. | Ajami S, Coathup MJ, Khoury J, et al. Augmenting the bioactivity of polyetheretherketone using a novel accelerated neutral atom beam technique. J Biomed Mater Res B Appl Biomater, 2017, 105(6): 1438-1446. |
36. | Khoury J, Maxwell M, Cherian RE, et al. Enhanced bioactivity and osseointegration of PEEK with accelerated neutral atom beam technology. J Biomed Mater Res B Appl Biomater, 2017, 105(3): 531-543. |
37. | Xu A, Liu X, Gao X, et al. Enhancement of osteogenesis on micro/nano-topographical carbon fiber-reinforced polyetheretherketone-nanohydroxyapatite biocomposite. Mater Sci Eng C Mater Biol Appl, 2015, 48: 592-598. |
38. | Novotna Z, Reznickova A, Rimpelova S, et al. Tailoring of PEEK bioactivity for improved cell interaction: plasma treatment in action. RSC Adv, 2015, 5(52): 41428-41436. |
39. | Noiset O, Schneider YJ, Marchand-Brynaert J. Surface modification of poly(aryl ether ether ketone) (PEEK) film by covalent coupling of amines and amino acids through a spacer arm. J Polym Sci Part A: Polym Chem, 1997, 35(17): 3779-3790. |
40. | Becker M, Lorenz S, Strand D, et al. Covalent grafting of the RGD-Peptide onto polyetheretherketone surfaces via schiff base formation. Sci World J, 2013: 616535. |
41. | Xu AX, Zhou LW, Deng Y, et al. A carboxymethyl chitosan and peptide-decorated polyetheretherketone ternary biocomposite with enhanced antibacterial activity and osseointegration as orthopedic/dental implants. J Mater Chem B, 2016, 4(10): 1878-1890. |
42. | Huang RY, Shao PH, Burns CM, et al. Sulfonation of poly(ether ether ketone) (PEEK): kinetic study and characterization. J Appl Polym Sci, 2001, 82(11): 2651-2660. |
43. | Daoust D, Devaux J, Godard P. Mechanism and kinetics of poly (ether ether ketone) (PEEK) sulfonation in concentrated sulfuric acid at room temperature. Part 3. General kinetic model of the sulfonation of PEEK fluoroarylketone chain-end repeat unit. Polym Int, 2001, 50(8): 932-936. |
44. | Ouyang L, Zhao Y, Jin G, et al. Influence of sulfur content on bone formation and antibacterial ability of sulfonated PEEK. Biomaterials, 2016, 83: 115-126. |
45. | Pino M, Stingelin N, Tanner KE. Nucleation and growth of apatite on NaOH-treated PEEK. HDPE and UHMWPE for artificial cornea materials. Acta Biomater, 2008, 4(6): 1827-1836. |
46. | Abu Bakar MS, Cheang P, Khor KA. Thermal processing of hydroxyapatite reinforced polyetheretherketone composites. J Mater Proc Tech, 1999, 89: 462-466. |
47. | Petrovic L, Pohle D, Munstedt H, et al. Effect of beta TCP filled polyetheretherketone on osteoblast cell proliferation in vitro. J Biomed Sci, 2006, 13(1): 41-46. |
48. | Abu Bakar MS, Cheang P, Khor KA. Mechanical properties of injection molded hydroxyapatite-polyetheretherketone biocomposites. Compos Sci Technol, 2003, 63(3/4): 421-425. |
49. | Tan KH, Chua CK, Leong KF, et al. Scaffold development using selective laser sintering of polyetheretherketone-hydroxyapatite biocomposite blends. Biomaterials, 2003, 24(18): 3115-3123. |
50. | Tang SM, Cheang P, Abubakar MS, et al. Tension-tension fatigue behavior of hydroxyapatite reinforced polyetheretherketone composites. Int J Fatigue, 2004, 26(1): 49-57. |
51. | Converse GL, Conrad TL, Merrill CH, et al. Hydroxyapatite whisker-reinforced polyetherketoneketone bone ingrowth scaffolds. Acta Biomater, 2010, 6(3): 856-863. |
52. | Ma R, Weng LQ, Fang L, et al. Structure and mechanical performance of in situ synthesized hydroxyapatite/ polyetheretherketone nanocomposite materials. J Solgel Sci Technol, 2012, 62(1): 52-56. |
53. | Ma R, Tang S, Tan H, et al. Preparation, characterization, and in vitro osteoblast functions of a nano-hydroxyapatite/ polyetheretherketone biocomposite as orthopedic implant material. Int J Nanomedicine, 2014, 9: 3949-3961. |
54. | Deng Y, Zhou P, Liu X, et al. Preparation, characterization, cellular response and in vivo osseointegration of polyetheretherketone/ nano-hydroxyapatite/carbon fiber ternary biocomposite. Colloids Surf B Biointerfaces, 2015, 136: 64-73. |
55. | Wang LX, He S, Wu XM, et al. Polyetheretherketone/nano-fluorohydroxyapatite composite with antimicrobial activity and osseointegration properties. Biomaterials, 2014, 35(25): 6758-6775. |
56. | Von Wilmowsky C, Vairaktaris E, Pohle D, et al. Effects of bioactive glass and beta-TCP containing three-dimensional laser sintered polyetheretherketone composites on osteoblasts in vitro. J Biomed Mater Res A, 2008, 87(4): 896-902. |
57. | Hu GF, Quan RF, Chen YM, et al. Fabrication, characterization, bioactivity, and biocompatibility of novel mesoporous calcium silicate/polyetheretherketone composites. RSC Adv, 2016, 6(62): S7131-S7137. |
58. | Balaji V, Tiwari AN, Goyal RK. Fabrication and properties of high performance PEEK/Si3N4 nanocomposites. J Appl Polym Sci, 2011, 119(1): 311-318. |
59. | Pezzotti G, Marin E, Adachi T, et al. Incorporating Si3N4 into PEEK to produce antibacterial, osteocondutive, and radiolucent spinal implants. Macromol Biosci, 2018, 18(6): e1800033. |
60. | Díez-Pascual AM, Díez-Vicente AL. Nano-TiO2 reinforced PEEK/PEI blends as biomaterials for load-bearing implant applications. ACS Appl Mater Interfaces, 2015, 7(9): 5561-5573. |
61. | Wu X, Liu X, Wei J, et al. Nano-TiO2/PEEK bioactive composite as a bone substitute material: in vitro and in vivo studies. Int J Nanomedicine, 2012, 7: 1215-1225. |
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69. | Tan KH, Chua CK, Leong KF, et al. Fabrication and characterization of three-dimensional poly(ether-ether-ketone)/-hydroxyapatite biocomposite scaffolds using laser sintering. Proc Inst Mech Eng H, 2005, 219(3): 183-194. |
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71. | Hieda A, Uemura N, Hashimoto Y, et al. In vivo bioactivity of porous polyetheretherketone with a foamed surface. Dent Mater J, 2017, 36(2): 222-229. |
- 1. Attwood TE, Dawson PC, Freeman JL, et al. Synthesis and properties of polyaryletherketones. Polymer, 1981, 22(8): 1096-1103.
- 2. Kurtz SM, Devine JN. PEEK biomaterials in trauma, orthopedic, and spinal implants. Biomaterials, 2007, 28(32): 4845-4869.
- 3. Fuhrmann G, Steiner M, Freitag-Wolf S, et al. Resin bonding to three types of polyaryletherketones (PAEKs)-durability and influence of surface conditioning. Dent Mater, 2014, 30(3): 357-363.
- 4. Kersten RF, van Gaalen SM, de Gast A, et al. Polyetheretherketone (PEEK) cages in cervical applications: a systematic review. Spine J, 2015, 15(6): 1446-1460.
- 5. Abdullah MR, Goharian A, Kadir MR, et al. Biomechanical and bioactivity concepts of polyetheretherketone composites for use in orthopedic implantsa review. J Biomed Mater Res A, 2015, 103(11): 3689-3702.
- 6. Moore R, Beredjiklian P, Rhoad R, et al. A comparison of the inflammatory potential of particulates derived from two composite materials. J Biomed Mater Res, 1997, 34(2): 137-147.
- 7. Mcgrail PT. Polyaromatics. Polym Int, 1996, 41(2): 103-121.
- 8. Converse GL, Conrad TL, Roeder RK. Mechanical properties of hydroxyapadite whisker reinforced polyetherketoneketone composite scaffolds. J Mech Behav Biomed Mater, 2009, 2(6): 627-635.
- 9. Yuan B, Chen YM, Lin H, et al. Processing and properties of bioactive surface-porous PEKK. ACS Biomater Sci Eng, 2016, 2(6): 977-986.
- 10. Yuan B, Cheng Q, Zhao R, et al. Comparison of osteointegration property between PEKK and PEEK: effects of surface structure and chemistry. Biomaterials, 2018, 170: 116-126.
- 11. Koehler S, Raslan F, Stetter C, et al. Autologous bone graft versus PEKK cage for vertebral replacement after 1-or 2-level anterior median corpectomy. J Neurosurg Spine, 2015, 13: 1-6.
- 12. Adamzyk C, Kachel P, Hoss M, et al. Bone tissue engineering using polyetherketoneketone scaffolds combined with autologous mesenchymal stem cells in a sheep calvarial defect model. J Craniomaxillofac Surg, 2016, 44(8): 985-994.
- 13. Deng Y, Liu X, Xu A, et al. Effect of surface roughness on osteogenesis in vitro and osseointegration in vivo of carbon fiber-reinforced polyetheretherketone-nanohydroxyapatite composite. Int J Nanomedicine, 2015, 10: 1425-1447.
- 14. Esposito M, Hirsch JM, Lekholm U, et al. Biological factors contributing to failures of osseointegrated oral implants. (Ⅱ). Etiopathogenesis. Eur J Oral Sci, 1998, 106(3): 721-764.
- 15. Togawa D, Bauer TW, Lieberman IH, et al. Lumbar intervertebral body fusion cages: histological evaluation of clinically failed cages retrieved from humans. J Bone and Joint Surg Am, 2004, 86A(1): 70-79.
- 16. Hahn H, Palich W. Preliminary evaluation of porous metal surfaced titanium for orthopedic implants. J Biomed Mater Res, 1970, 4(4): 571-577.
- 17. Sun L, Berndt CC, Gross KA, et al. Material fundamentals and clinical performance of plasma-sprayed hydroxyapatite coatings: a review. J Biomed Mater Res, 2001, 58(5): 570-592.
- 18. Hahn BD, Park DS, Choi JJ, et al. Osteoconductive hydroxyapatite coated PEEK for spinal fusion surgery. Appl Surf Sci, 2013, 283: 6-11.
- 19. Walsh WR, Bertollo N, Christou C, et al. Plasma-sprayed titanium coating to polyetheretherketone improves the bone-implant interface. Spine J, 2015, 15(5): 1041-1049.
- 20. Han CM, Jang TS, Kim HE, et al. Creation of nanoporous TiO2 surface onto polyetheretherketone for effective immobilization and delivery of bone morphogenetic protein. J Biomed Mater Res A, 2014, 102(3): 793-800.
- 21. Huang JX, Wan SH, Wang LP, et al. Tribological properties of Si-doped graphite-like amorphous carbon film of PEEK rubbing with different counterparts in SBF medium. Tribol Lett, 2015, 57(1): 1-9.
- 22. Ouyang L, Deng Y, Yang L, et al. Graphene-oxide-decorated microporous polyetheretherketone with superior antibacterial capability and in vitro osteogenesis for orthopedic implant. Macromol Biosci, 2018, 18(6): e1800036.
- 23. Suska F, Omar O, Emanuelsson L, et al. Enhancement of CRF-PEEK osseointegration by plasma-sprayed hydroxyapatite: a rabbit model. J Biomater Appl, 2014, 29(2): 234-242.
- 24. Lee JH, Jang HL, Lee KM, et al. In vitro and in vivo evaluation of the bioactivity of hydroxyapatite-coated polyetheretherketone biocomposites created by cold spray technology. Acta Biomater, 2013, 9(4): 6177-6187.
- 25. Wen J, Lu T, Wang X, et al. In vitro and in vivo evaluation of silicate-coated polyetheretherketone fabricated by electron beam evaporation. ACS Appl Mater Interfaces, 2016, 8(21): 13197-13206.
- 26. Shimizu T, Fujibayashi S, Yamaguchi S, et al. Bioactivity of sol-gel-derived TiO2 coating on polyetheretherketone: in vitro and in vivo studies. Acta Biomater, 2016, 35: 305-317.
- 27. Chen M, Ouyang L, Lu T, et al. Enhanced bioactivity and bacteriostasis of surface fluorinated polyetheretherketone. ACS Appl Mater Interfaces, 2017, 9(20): 16824-16833.
- 28. Liu X, Gan K, Liu H, et al. Antibacterial properties of nano-silver coated PEEK prepared through magnetron sputtering. Dent Mater, 2017, 33(9): e348-e360.
- 29. Gümüş S, Polat Ş, Waldhauser W, et al. Biodegradation of anti-microbial titanium-magnesium-silver coatings on polyetheretherketone for bone-contact applications. Surf Coat Tech, 2017, 320: 503-511.
- 30. Deng Y, Yang L, Huang X, et al. Dual Ag/ZnO-decorated micro-/nanoporous sulfonated polyetheretherketone with superior antibacterial capability and biocompatibility via layer-by-layer self-assembly strategy. Macromol Biosci, 2018, 18(7): e1800028.
- 31. Ouyang L, Qi MY, Wang SN, et al. Osteogenesis and antibacterial activity of graphene oxide and dexamethasone coatings on porous polyetheretherketone via polydopamine-assisted chemistry. Coatings, 2018, 8(6): 203.
- 32. Hiruta T, Yabutsuka T, Watanabe S, et al. Apatite formation ability of bioactive bearing grade polyetheretherketone fabricated by incorporation of apatite nuclei. Key Eng Mater, 2017, 758: 69-74.
- 33. Ha SW, Kirch M, Birchler F, et al. Surface activation of polyetheretherketone (PEEK) and formation of calcium phosphate coatings by precipitation. J Mater Sci Mater Med, 1997, 8(11): 683-690.
- 34. Waser-Althaus J, Salamon A, Waser M, et al. Differentiation of human mesenchymal stem cells on plasma-treated polyetheretherketone. J Mater Sci Mater Med, 2014, 25(2): 515-525.
- 35. Ajami S, Coathup MJ, Khoury J, et al. Augmenting the bioactivity of polyetheretherketone using a novel accelerated neutral atom beam technique. J Biomed Mater Res B Appl Biomater, 2017, 105(6): 1438-1446.
- 36. Khoury J, Maxwell M, Cherian RE, et al. Enhanced bioactivity and osseointegration of PEEK with accelerated neutral atom beam technology. J Biomed Mater Res B Appl Biomater, 2017, 105(3): 531-543.
- 37. Xu A, Liu X, Gao X, et al. Enhancement of osteogenesis on micro/nano-topographical carbon fiber-reinforced polyetheretherketone-nanohydroxyapatite biocomposite. Mater Sci Eng C Mater Biol Appl, 2015, 48: 592-598.
- 38. Novotna Z, Reznickova A, Rimpelova S, et al. Tailoring of PEEK bioactivity for improved cell interaction: plasma treatment in action. RSC Adv, 2015, 5(52): 41428-41436.
- 39. Noiset O, Schneider YJ, Marchand-Brynaert J. Surface modification of poly(aryl ether ether ketone) (PEEK) film by covalent coupling of amines and amino acids through a spacer arm. J Polym Sci Part A: Polym Chem, 1997, 35(17): 3779-3790.
- 40. Becker M, Lorenz S, Strand D, et al. Covalent grafting of the RGD-Peptide onto polyetheretherketone surfaces via schiff base formation. Sci World J, 2013: 616535.
- 41. Xu AX, Zhou LW, Deng Y, et al. A carboxymethyl chitosan and peptide-decorated polyetheretherketone ternary biocomposite with enhanced antibacterial activity and osseointegration as orthopedic/dental implants. J Mater Chem B, 2016, 4(10): 1878-1890.
- 42. Huang RY, Shao PH, Burns CM, et al. Sulfonation of poly(ether ether ketone) (PEEK): kinetic study and characterization. J Appl Polym Sci, 2001, 82(11): 2651-2660.
- 43. Daoust D, Devaux J, Godard P. Mechanism and kinetics of poly (ether ether ketone) (PEEK) sulfonation in concentrated sulfuric acid at room temperature. Part 3. General kinetic model of the sulfonation of PEEK fluoroarylketone chain-end repeat unit. Polym Int, 2001, 50(8): 932-936.
- 44. Ouyang L, Zhao Y, Jin G, et al. Influence of sulfur content on bone formation and antibacterial ability of sulfonated PEEK. Biomaterials, 2016, 83: 115-126.
- 45. Pino M, Stingelin N, Tanner KE. Nucleation and growth of apatite on NaOH-treated PEEK. HDPE and UHMWPE for artificial cornea materials. Acta Biomater, 2008, 4(6): 1827-1836.
- 46. Abu Bakar MS, Cheang P, Khor KA. Thermal processing of hydroxyapatite reinforced polyetheretherketone composites. J Mater Proc Tech, 1999, 89: 462-466.
- 47. Petrovic L, Pohle D, Munstedt H, et al. Effect of beta TCP filled polyetheretherketone on osteoblast cell proliferation in vitro. J Biomed Sci, 2006, 13(1): 41-46.
- 48. Abu Bakar MS, Cheang P, Khor KA. Mechanical properties of injection molded hydroxyapatite-polyetheretherketone biocomposites. Compos Sci Technol, 2003, 63(3/4): 421-425.
- 49. Tan KH, Chua CK, Leong KF, et al. Scaffold development using selective laser sintering of polyetheretherketone-hydroxyapatite biocomposite blends. Biomaterials, 2003, 24(18): 3115-3123.
- 50. Tang SM, Cheang P, Abubakar MS, et al. Tension-tension fatigue behavior of hydroxyapatite reinforced polyetheretherketone composites. Int J Fatigue, 2004, 26(1): 49-57.
- 51. Converse GL, Conrad TL, Merrill CH, et al. Hydroxyapatite whisker-reinforced polyetherketoneketone bone ingrowth scaffolds. Acta Biomater, 2010, 6(3): 856-863.
- 52. Ma R, Weng LQ, Fang L, et al. Structure and mechanical performance of in situ synthesized hydroxyapatite/ polyetheretherketone nanocomposite materials. J Solgel Sci Technol, 2012, 62(1): 52-56.
- 53. Ma R, Tang S, Tan H, et al. Preparation, characterization, and in vitro osteoblast functions of a nano-hydroxyapatite/ polyetheretherketone biocomposite as orthopedic implant material. Int J Nanomedicine, 2014, 9: 3949-3961.
- 54. Deng Y, Zhou P, Liu X, et al. Preparation, characterization, cellular response and in vivo osseointegration of polyetheretherketone/ nano-hydroxyapatite/carbon fiber ternary biocomposite. Colloids Surf B Biointerfaces, 2015, 136: 64-73.
- 55. Wang LX, He S, Wu XM, et al. Polyetheretherketone/nano-fluorohydroxyapatite composite with antimicrobial activity and osseointegration properties. Biomaterials, 2014, 35(25): 6758-6775.
- 56. Von Wilmowsky C, Vairaktaris E, Pohle D, et al. Effects of bioactive glass and beta-TCP containing three-dimensional laser sintered polyetheretherketone composites on osteoblasts in vitro. J Biomed Mater Res A, 2008, 87(4): 896-902.
- 57. Hu GF, Quan RF, Chen YM, et al. Fabrication, characterization, bioactivity, and biocompatibility of novel mesoporous calcium silicate/polyetheretherketone composites. RSC Adv, 2016, 6(62): S7131-S7137.
- 58. Balaji V, Tiwari AN, Goyal RK. Fabrication and properties of high performance PEEK/Si3N4 nanocomposites. J Appl Polym Sci, 2011, 119(1): 311-318.
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