Preparation and Properties of the PVA/CF/n-HA Composite Hydrogel

At present, the blindness rate caused by corneal disease is very high; the donor corneas are of serious shortage, so the research of artificial cornea material is necessity and urgency. Artificial cornea is made of medical polymer materials and similar to the human cornea, including two parts of the optical microscope column and peripheral stents. The present research focuses on the scaffold material part. The polyvinyl alcohol (PVA)/carbon fiber (CF)/n-hydroxyapatite (n-HA) composite hydrogel was prepared by cyclic freezing as scaffold around artificial cornea. These hydrogels are porous materials which are easy to combine with human tissue. The mechanical properties and moisture content of the composite hydrogel were tested, and the composition and morphology were studied by X-ray diffraction (XRD), thermo gravimetric analysis (TGA), scanning electronic microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. The results show that the tensile strength of the composite hydrogel is 0.73 similar to 1.02 MPa, and the moisture content is 68.0%similar to 74.9%. When the molar ratio of CF and n-HA is 3:2, the tensile strength is 0.98 MPa, the elongation at break is 368.3%, and the moisture content of the hydrogel composite is 71.1%, which meet the requirements of artificial cornea scaffold materials. Many mutually penetrating holes exist in the material, which will facilitate the ingrowths of fibrous tissue.