Prestress-reinforced light high-strength controllable-degradation medical composite material and preparation method thereof

Abstract

The invention relates to a prestress-reinforced light high-strength controllable-degradation medical composite material and a preparation method thereof. The medical composite material is characterized in that a magnesium alloy wire subjected to prestress processing is taken as a reinforced phase to improve strength and stiffness of the composite material, an absorbable high polymer material is taken as a matrix, and meanwhile, the early-stage degradation velocity of the composite material can be further regulated and controlled by regulating the thickness of a shell protection layer formed by the high polymer material of the matrix. According to the composite material, bars or plates are manufactured by utilizing methods of thermal die pressing, extrusion or drawing or the like, and various degradable high-toughness bone repairing and fixing instruments such as bone nails and bone plates can be obtained by carrying out subsequent machining; and compared with the conventional absorbable polymer bone surgery instruments, the composite material has the advantages that the mechanical fixing effect is relatively good, and furthermore, the problems that the degradation speed of the absorbable magnesium alloy bone surgery instruments is difficult to control and the hydrogen release quantity during degradation is large and the like can be overcome.

Description

technical field

[0001] The invention relates to a bioactive and controllable degradable orthopedic fixation material in a medical device, belonging to the field of biomedical devices. Specifically, it is a prestressed reinforced light-weight, high-strength, controllable degradable medical composite material. The composite material uses prestressed absorbable magnesium alloy wire as the reinforcing phase, and the matrix is ​​absorbable polylactic acid, polyglycolic acid, One of polycaprolactone, polyethylene glycol, polyamide, or a copolymer or blend of two or more of them, and the outer surface of the composite material is a layer of polymer matrix with a thickness greater than 0.1mm The protective shell formed by the material. Background technique

[0002] The selection of internal bone fixation materials has always been one of the problems faced by orthopedic surgery. Traditional internal bone fixation materials are mainly metals, such as titanium alloys, stainless steel,...

Examples

Embodiment 1

[0034] The selected polymer matrix is ​​PLLA polylactic acid with a molecular weight of 160,000 to 200,000; the composition of the magnesium alloy wire is AZ31B, the yield strength is 220MPa, the diameter is 0.32mm, and the volume fraction is 5%, 10%, and 20%; The ribs are the same as the reinforced magnesium alloy wire.

[0035] Perform micro-arc oxidation treatment on the surface of the magnesium alloy wire, use 10g / L sodium silicate, 2g / LNaOH and 10g / L hydroxyapatite nanoparticles as the micro-arc oxidation electrolyte system, and immerse the magnesium alloy wire in it, Apply a voltage of 400V and perform micro-arc oxidation treatment for 10 minutes to form a ceramic protective layer rich in magnesium oxide, magnesium silicate and hydroxyapatite in situ on the surface.

[0036] Magnesium alloy wires are oriented parallel to the axial direction of the composite material, and then tensile stress is applied to both ends, and then the stirrups are bound (see attached Figure 4...

Embodiment 2

[0042] PLA and PGA copolymer PLGA is selected as the polymer matrix. Relevant studies have shown that the degradation half-life of PLGA is related to the content of PGA: when the PGA content is less than 20%, the degradation half-life decreases significantly with the increase of the content; the content is 20% to 80%. %, the degradation half-life first decreases slowly, reaches the minimum at 50%, and then increases slowly; after exceeding 80%, the degradation half-life increases rapidly again. The PLGA selected in this example is synthesized by copolymerization of 15% PGA and 85% PLA, with a molecular weight of 150,000 to 200,000; the diameter of the magnesium alloy wire is 0.8 mm, the composition is MB8, the yield strength is 170 MPa, and the volume fraction is 9 %; The stirrup material and surface treatment method are the same as the reinforced magnesium alloy wire, with a diameter of 0.5mm.

[0043] Phosphate treatment on the surface of magnesium alloy wire, the solution i...

Embodiment 3

[0050] The selected polymer matrix is ​​a blend copolymer of polylactic acid-polycaprolactone (PLA-PCL); the magnesium alloy wire is QE22, with a diameter of 0.5mm and a volume fraction of 20%; stirrups and reinforced magnesium alloy wire same. Use 10g / L sodium silicate, 3g / L hydroxyapatite nanopowder, and 2g / LNaOH as the micro-arc oxidation electrolyte system, immerse the magnesium alloy wire in it, apply a voltage of 400V, and perform micro-arc oxidation for 15 minutes treatment to generate magnesium oxide and hydroxyapatite composite ceramic protective layer on the surface in situ.

[0051] Magnesium alloy wires are oriented parallel to the axial direction of the composite material, and then tensile stress is applied to both ends. The tensile stress is 20% of the yield strength of the magnesium alloy wires, and then the stirrups are tied. The alloy wires are fixedly arranged in the cavity of the mould. The polymer solution in the molten state is injected into the mold cav...

technical field

[0001] The invention relates to a bioactive and controllable degradable orthopedic fixation material in a medical device, belonging to the field of biomedical devices. Specifically, it is a prestressed reinforced light-weight, high-strength, controllable degradable medical composite material. The composite material uses prestressed absorbable magnesium alloy wire as the reinforcing phase, and the matrix is ​​absorbable polylactic acid, polyglycolic acid, One of polycaprolactone, polyethylene glycol, polyamide, or a copolymer or blend of two or more of them, and the outer surface of the composite material is a layer of polymer matrix with a thickness greater than 0.1mm The protective shell formed by the material. Background technique

[0002] The selection of internal bone fixation materials has always been one of the problems faced by orthopedic surgery. Traditional internal bone fixation materials are mainly metals, such as titanium alloys, stainless steel,...

Examples

Embodiment 1

[0034] The selected polymer matrix is ​​PLLA polylactic acid with a molecular weight of 160,000 to 200,000; the composition of the magnesium alloy wire is AZ31B, the yield strength is 220MPa, the diameter is 0.32mm, and the volume fraction is 5%, 10%, and 20%; The ribs are the same as the reinforced magnesium alloy wire.

[0035] Perform micro-arc oxidation treatment on the surface of the magnesium alloy wire, use 10g / L sodium silicate, 2g / LNaOH and 10g / L hydroxyapatite nanoparticles as the micro-arc oxidation electrolyte system, and immerse the magnesium alloy wire in it, Apply a voltage of 400V and perform micro-arc oxidation treatment for 10 minutes to form a ceramic protective layer rich in magnesium oxide, magnesium silicate and hydroxyapatite in situ on the surface.

[0036] Magnesium alloy wires are oriented parallel to the axial direction of the composite material, and then tensile stress is applied to both ends, and then the stirrups are bound (see attached Figure 4...

Embodiment 2

[0042] PLA and PGA copolymer PLGA is selected as the polymer matrix. Relevant studies have shown that the degradation half-life of PLGA is related to the content of PGA: when the PGA content is less than 20%, the degradation half-life decreases significantly with the increase of the content; the content is 20% to 80%. %, the degradation half-life first decreases slowly, reaches the minimum at 50%, and then increases slowly; after exceeding 80%, the degradation half-life increases rapidly again. The PLGA selected in this example is synthesized by copolymerization of 15% PGA and 85% PLA, with a molecular weight of 150,000 to 200,000; the diameter of the magnesium alloy wire is 0.8 mm, the composition is MB8, the yield strength is 170 MPa, and the volume fraction is 9 %; The stirrup material and surface treatment method are the same as the reinforced magnesium alloy wire, with a diameter of 0.5mm.

[0043] Phosphate treatment on the surface of magnesium alloy wire, the solution i...

Embodiment 3

[0050] The selected polymer matrix is ​​a blend copolymer of polylactic acid-polycaprolactone (PLA-PCL); the magnesium alloy wire is QE22, with a diameter of 0.5mm and a volume fraction of 20%; stirrups and reinforced magnesium alloy wire same. Use 10g / L sodium silicate, 3g / L hydroxyapatite nanopowder, and 2g / LNaOH as the micro-arc oxidation electrolyte system, immerse the magnesium alloy wire in it, apply a voltage of 400V, and perform micro-arc oxidation for 15 minutes treatment to generate magnesium oxide and hydroxyapatite composite ceramic protective layer on the surface in situ.

[0051] Magnesium alloy wires are oriented parallel to the axial direction of the composite material, and then tensile stress is applied to both ends. The tensile stress is 20% of the yield strength of the magnesium alloy wires, and then the stirrups are tied. The alloy wires are fixedly arranged in the cavity of the mould. The polymer solution in the molten state is injected into the mold cav...

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