Abstract

The present invention provides a surface coating with strong binding for a medical magnesium alloy and a method for preparing same, and relates to the technical field of biomedical metal materials. The surface coating comprises an inner layer and an outer layer. The inner layer is a magnesium phosphate/calcium phosphate layer attached to the surface of the medical magnesium alloy, and the outer layer is a hydrophobic polymer layer attached to the surface of the inner layer. The method comprises the following steps: S1, conducting surface treatment on the medical magnesium alloy substrate; S2, preparing a solution containing a magnesium/calcium salt and phosphoric acid/phosphate, adjusting the pH of the prepared solution, and heating the prepared solution; S3, soaking the medical magnesium alloy substrate in the preparation solution, washing, and drying to give a medical magnesium alloy sample coated with a magnesium phosphate/calcium phosphate layer on the surface; and S4, preparing a hydrophobic polymer coating on the surface of the medical magnesium alloy sample by means of vapor deposition. According to the present invention, a magnesium phosphate/calcium phosphate layer is arranged between a hydrophobic polymer coating and the medical magnesium alloy substrate, thus solving the problem of the insufficient binding force between the hydrophobic polymer coating and the medical magnesium alloy substrate and ease of peeling-off.

IPC Classes  ?

• A61L 27/34 - Macromolecular materials
• A61L 27/32 - Phosphorus-containing materials, e.g. apatite
• A61L 27/04 - Metals or alloys
• A61L 27/50 - Materials characterised by their function or physical properties
• A61L 27/54 - Biologically active materials, e.g. therapeutic substances
• C23C 22/22 - Orthophosphates containing alkaline earth metal cations

Abstract

A surface coating for degradable magnesium and magnesium alloys, including: an inner layer and an outer layer. The inner layer is a magnesium phosphate conversion layer, and the outer layer is a hydroxyapatite layer. A method for fabricating the surface coating is also provided herein, which includes: soaking the magnesium or magnesium alloy in an acidic solution containing magnesium salt and phosphate under heating to form the magnesium phosphate conversion layer on a surface of the magnesium or magnesium alloy; and transferring the magnesium or magnesium alloy to an alkaline solution containing calcium salt and phosphate followed by soaking under heating to form a hydroxyapatite layer on a surface of the magnesium phosphate conversion layer.

IPC Classes  ?

• C23C 22/08 - Orthophosphates
• C23C 22/82 - After-treatment

Abstract

A coating with strong adhesion for medical magnesium alloys, including a magnesium phosphate or calcium phosphate layer as an inner layer and a hydrophobic polymer layer as an outer layer. The inner layer is attached to the medical magnesium alloy; and the outer layer is attached to the inner layer. A preparation method of the coating is also provided, including: (S1) carrying out surface treatment on a medical magnesium alloy substrate; (S2) preparing a solution including magnesium salt/calcium salt and phosphoric acid/phosphate followed by pH adjustment and heating; (S3) soaking the medical magnesium alloy substrate in the solution followed by washing and drying to obtain a magnesium phosphate/calcium phosphate layer-coated medical magnesium alloy sample; and (S4) depositing a hydrophobic polymer layer on the medical magnesium alloy sample through chemical vapor deposition (CVD).

IPC Classes  ?

• A61L 31/08 - Materials for coatings
• C23C 22/22 - Orthophosphates containing alkaline earth metal cations
• B05D 1/00 - Processes for applying liquids or other fluent materials
• B05D 3/10 - Pretreatment of surfaces to which liquids or other fluent materials are to be appliedAfter-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by other chemical means
• A61L 31/02 - Inorganic materials
• A61L 31/16 - Biologically active materials, e.g. therapeutic substances
• A61L 31/10 - Macromolecular materials

Abstract

Disclosed in the present invention are a surface coating capable of degrading magnesium and a magnesium alloy, and a preparation method therefor. The surface coating comprises an inner layer and an outer layer; the inner layer is a magnesium phosphate salt conversion layer; and the outer layer is a hydroxyapatite coating. The coating prepared by the present invention is of a double-layer structure, and the magnesium phosphate salt conversion layer of the inner layer provides growth sites for the hydroxyapatite coating of the outer layer, so that the binding force of the coating and a base material is effectively enhanced, and the bonding strength can reach 50 MPa or above. In addition, the thickness of the hydroxyapatite coating is controllable, the degradation time can be adjusted according to needs, and the degradation time of a magnesium alloy implant can be controlled to be 12-18 months.

IPC Classes  ?

• C23C 22/08 - Orthophosphates
• C23C 22/82 - After-treatment