Effect Of T-ZnOw/?-TCP Addition On The Mechanical Properties And Degradability Of 58S Bioactive Glass-ceramics

The mechanical properties and degradability of bioactive glass-ceramics used in bone tissue engineering are still not ideal.In this paper,the bioactive glass with composition of SiO₂-CaO-P₂O₅ prepared by sol-gel method was used as the base glass.On this basis,the effect of different component and heat treatment process on the crystallization of glass-ceramics were discussed?On the basis of 58SiO₂-38CaO-4P₂O₅ bioactive glass,the degradability of58S bioactive glass and?-tricalcium phosphate??-TCP?was investigated,and the effect of different content of tetra-needle-like ZnO whiske?T-ZnO_w?and?-TCP on the biological activities,mechanical properties and degradability of 58S glass-ceramics were discussed.Through research previously,the conclusions are as follows:?1?Different content of T-ZnO_w were added to 58S bioavtive glass to abtain 58S bioavtive glass-ceramics.When the T-ZnO_w content is no higher than 2.5wt%,58S bioactive glass-ceramics still had the ability to form a large amount of apatite,and still showed biological activity.And the degradability of 58S glass-ceramics was still relatively good.When the T-ZnO_w content is no less than 5wt%,the surface of 58S glass-ceramics did not form apatite due to the crystallization of hardystonite?Ca₂ZnSi₂O₇?,so it losed biological activity.And the formation of hardystonite increases the stability of the structure of 58S glass-ceramics,thus dramatically reducing the degradability of the glass-ceramics.The weight loss of 58S glass-ceramics decreases from 12.95wt%to about 2wt%after immersion for 14 days in SBF.When the T-ZnO_w content is no higher than 2.5wt%,the elastic modulus of 58S glass-ceramics rose to 4GPa with the increase of the T-ZnO_w content.When the T-ZnO_w content is no less than5wt%,its elastic modulus decreases continuously until 3GPa with the increase of the T-ZnO_w content.The compressive strength of 58S glass-ceramics increased with the rising of T-ZnO_w content,increasing from about 13MPa without doping to 21.6MPa with 15wt%doping.?2?We selected 58S glass-ceramics doped with 2.5wt%and 10wt%T-ZnO_w,and doped with 0wt%,10wt%and 30wt%?-TCP,respectively,to prepare 58S bioactive glass-ceramics doped with T-ZnO_w/?-TCP.When 58S glass-cermics doped with?-TCP containing 2.5wt%T-ZnO_w,their compressive strength and elastic modulus were basically lower than those containing 10wt%T-ZnO_w,and the compressive strength increased from 14 MPa to 17.1 MPa,the elastic modulus increased from 3.9GPa to 4.6GPa with the increasing of?-TCP content.The biological activity of 58S glass-ceramics was good,and its degradability increased from4.6wt%to 6.5wt%with the?-TCP content increasing from 0wt%to 30wt%.When 58S glass-cermics doped with?-TCP containing 10wt%T-ZnO_w,and the compressive strength decreased from 19.6 MPa to 17.2 MPa,the elastic modulus increased from 5.3GPa to 5.8GPa with the increase of?-TCP content;The 58S glass-cermics still had no biological activity,while its degradability increased from 2.5wt%to 2.9wt%with the?-TCP content increasing.