CN112679760B - Preparation method of glass fiber reinforced biodegradable polymer composite material - Google Patents
Preparation method of glass fiber reinforced biodegradable polymer composite material Download PDFInfo
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Abstract
The invention relates to the field of biological materials, and particularly discloses a preparation method of a glass fiber reinforced biodegradable polymer composite material. The invention provides a composition for enhancing biodegradability, which improves the strength of a biodegradable polymer material through glass fiber reinforcement, and prevents the formation of cavities by utilizing alkalescence generated by dissolution of glass fibers after being implanted into a human body and neutralizing the acidity of degradation products. Solves the problems that the bone nail and the bone lamella can form a cavity after being degraded and are easy to be twisted off during the operation. The composite material has good toughness and good biocompatibility.
Description
Technical Field
The invention relates to the field of biological materials, in particular to a preparation method of a glass fiber reinforced biodegradable polymer composite material.
Background
Biodegradable polymer materials generally face two problems when used as bone repair medical devices such as bone screws and bone plates: firstly, the acidity of the degradation product causes long-term inflammatory reaction, bone cells are difficult to grow in, and cavities can be formed after the absorbable bone nails and bone plates are degraded; secondly, the strength and toughness of the material are not enough, and the material is easy to twist off during operation. The first solution to the problem at present is to compound hydroxyapatite or calcium phosphate with biodegradable polymer, and neutralize the acidity of the degradation product by using the alkalinity of the biodegradable polymer, so as to avoid the generation of voids. However, both hydroxyapatite and calcium phosphate are directly filled into the biodegradable polymer material in the form of powder, and the strength of the biodegradable polymer material after compounding is sharply reduced due to poor compatibility between the two materials.
The method for enhancing the strength of the high polymer material in the prior art is to form a compound by initiating the polymerization of polylactic acid through hydroxyl on the surface of hydroxyapatite, and then mix the compound with the polylactic acid as a filler. However, the weight percentage of the hydroxyapatite in the composite material is usually less than 15%, and the strength is also sharply reduced beyond the value, so that the use requirement cannot be met. The existing solution of the second problem is that the toughness of the biodegradable polymer material can be greatly enhanced by a self-enhancement process for refining grains of the biodegradable polymer material, but the strength of the biodegradable polymer material is still low, and the biodegradable polymer material cannot be used for bone repair of a bearing part. And the method cannot solve the problem of cavities caused by the acidity of the degradation products.
Therefore, a polymer composite material with enhanced biodegradability is needed to solve the above problems.
Disclosure of Invention
The invention provides a preparation method of a glass fiber reinforced biodegradable polymer composite material for solving the problems of strength, toughness and acidity of degradation products of the glass fiber reinforced biodegradable polymer composite material.
One of the purposes of the invention is to provide a preparation method of a high polymer composite material for enhancing biodegradability, which has the following specific technical scheme:
a preparation method of a high polymer composite material for enhancing biodegradability comprises the following steps:
(1) mixing glass fiber and biodegradable material monomer, and carrying out catalytic reaction, wherein the biodegradable material monomer is at least one of Glycolide (GA), Lactide (LA), p-dioxanone (PDO) and epsilon-Caprolactone (CL);
(2) dissolving the product obtained in the step (1) by using an organic solvent, purifying and drying to obtain modified glass fiber;
(3) mixing the modified glass fiber with a biodegradable high polymer material, dissolving the mixture by an organic solvent, and casting to obtain the high polymer composite material, wherein the biodegradable high polymer material is at least one of polyglycolide, polylactide, polydioxanone, polycaprolactone and copolymers thereof.
Further, the mass ratio of the glass fiber to the biodegradable material monomer is 1: 2-20.
Further, the catalyst in the catalytic reaction in the step (1) is stannous octoate with the concentration of 50-500 ppm.
Further, the temperature of the catalytic reaction in the step (1) is 90-170 ℃.
Preferably, the catalytic reaction needs to be carried out for 5-72 hours under the protection of vacuum or inert gas.
Further, the organic solvent in step (2) is chloroform, and the purification step is performed in ethanol.
Further, the mass ratio of the modified glass fiber to the biodegradable polymer material in the step (3) is 1: 1-10.
Further, in the step (3), the organic solvent is chloroform or hexafluoroisopropanol.
Furthermore, the solvent needs to be volatilized after the casting in the step (3).
The purification in the preparation process can reduce the residual rate of the biodegradable material monomer, improve the material strength and prolong the degradation time. In addition, the interface compatibility of the glass fiber modified by the biodegradable high polymer material obtained by purification and subsequent biodegradable high polymer material compounding can be improved, and a tensile strength test proves that the tensile strength obtained by directly compounding the glass fiber and the biodegradable high polymer without surface modification is only 12-16 MPa, and the tensile strength of the composite material subjected to surface polymerization modification initiated by the biodegradable high polymer monomer can reach 23-34 MPa.
The second purpose of the present invention is to provide a biodegradable reinforced polymer composite material prepared by the preparation method in the above technical scheme.
The weight percentage of the glass fiber in the high polymer material prepared by the preparation method is 5-70%, the toughness is good, the problem of acidity of degradation products can be solved, and the high polymer material has good biocompatibility.
The invention has the advantages that: the invention uses the surface hydroxyl of the glass fiber to initiate ring-opening polymerization, firstly mixes, polymerizes and purifies the glass fiber and the biodegradable material monomer to obtain the biodegradable high polymer material modified glass fiber, increases the interfacial compatibility of the biodegradable high polymer material modified glass fiber and the subsequent biodegradable high polymer material, and the purification step can reduce the residual rate of the biodegradable material monomer, improve the material strength and prolong the degradation time, so that the composite material has higher toughness and can neutralize the acidity of the degradation product.
Drawings
FIG. 1 is a SEM image of a cross section of a glass fiber reinforced biodegradable polymer composite material of the present invention
Detailed Description
The present invention will be described in further detail with reference to the following examples and drawings, it being understood that the present invention is not limited to the particular examples described herein, but is capable of modification in various forms and details, and can be modified within the spirit and scope of the invention.
DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION
A preparation method of a glass fiber reinforced biodegradable polymer composite material comprises the following steps:
(1) mixing glass fiber with at least one of Glycolide (GA), Lactide (LA), p-dioxanone (PDO) and epsilon-Caprolactone (CL), wherein the mass ratio of the glass fiber to the biodegradable material monomer is 1: 2-20, adding 50-500ppm of stannous octoate as a catalyst, and reacting for 5-72 hours at 90-170 ℃ under vacuum or under the protection of inert gases such as nitrogen or argon. Dissolving the product with chloroform, separating out glass fiber, precipitating and purifying in ethanol to reduce the residual rate of biodegradable material monomer, raise the strength of the material and prolong the degradation time. And (3) drying in vacuum to obtain the glass fiber with the surface modified by the biodegradable high polymer material.
(2) Mixing the modified glass fiber with at least one of polyglycolide, polylactide, polydioxanone, polycaprolactone and copolymers thereof, wherein the mass ratio of the modified glass fiber to the biodegradable polymer material is 1:1 to 10. Then dissolved by an organic solvent such as chloroform or hexafluoroisopropanol, the weight percentage of the glass fiber is 5-70%. And casting the obtained solution into a film, and volatilizing the solvent to obtain the glass fiber reinforced biodegradable polymer composite material.
The method is mainly characterized in that the surface hydroxyl of the glass fiber is used for initiating ring-opening polymerization and purifying to obtain the glass fiber modified by the biodegradable high polymer material, and the interfacial compatibility of the glass fiber and the subsequent biodegradable high polymer material is improved.
Example 1
(1) Mixing glass fiber and Lactide (LA) monomer (the mass ratio of the glass fiber to the monomer is 1: 2), adding 50ppm of stannous octoate as a catalyst, reacting for 72 hours at 130 ℃ under a vacuum condition, dissolving the product with chloroform, separating out the glass fiber, precipitating and purifying in ethanol, and drying under a vacuum condition to obtain the polylactide surface modified glass fiber.
(2) Mixing the modified glass fiber and polylactide according to the mass ratio of 1:5, and dissolving the mixture in chloroform. And (3) casting the obtained solution into a film, and volatilizing the solvent to obtain the glass fiber reinforced polylactide polymer composite material, wherein the glass fiber is fully combined with the polylactide as shown in figure 1. In the figure, the glass fibers are uniformly dispersed in the polylactide matrix and are arranged in a layer shape, and the interfacial compatibility between the glass fibers and the polylactide is good.
Example 2
(1) Mixing glass fiber and epsilon-Caprolactone (CL) monomer (the mass ratio of the glass fiber to the monomer is 1: 10), adding 500ppm of stannous octoate as a catalyst, reacting for 5 hours at 170 ℃ under the protection of inert gas, dissolving the product with chloroform, separating out the glass fiber, precipitating and purifying in ethanol, and drying in vacuum to obtain the polycaprolactone surface-modified glass fiber.
(2) Mixing the modified glass fiber and polycaprolactone according to the mass ratio of 1:10, and dissolving in chloroform. And casting the obtained solution into a film, and volatilizing the solvent to obtain the glass fiber reinforced polycaprolactone polymer composite material.
Example 3
(1) Mixing glass fiber and a p-dioxanone monomer in a mass ratio of 1:20, adding 200ppm of stannous octoate serving as a catalyst, and reacting for 60 hours at 90 ℃ under the protection of inert gas. And dissolving the product by using hexafluoroisopropanol, separating out the glass fiber, precipitating and purifying in ethanol, and drying in vacuum to obtain the poly (p-dioxanone) surface modified glass fiber.
(2) Mixing the modified glass fiber and polydioxanone according to the mass ratio of 1:5, and dissolving in hexafluoroisopropanol. And casting the obtained solution into a film, and volatilizing the solvent to obtain the glass fiber reinforced poly (p-dioxanone) macromolecular composite material.
Example 4
(1) Mixing glass fiber with a mixed monomer of glycolide and lactide (the molar ratio is 1:1) and the mass ratio of the glass fiber to the monomer is 1:10, adding 100ppm of stannous octoate as a catalyst, and reacting for 12 hours at 160 ℃ under the protection of inert gas. And dissolving the product by using chloroform, separating out the glass fiber, precipitating and purifying in ethanol, and drying in vacuum to obtain the poly (glycolide-r-lactide) surface modified glass fiber.
(2) Mixing the modified glass fiber and polycaprolactone according to the mass ratio of 1:10, and dissolving in chloroform. And casting the obtained solution into a film, and volatilizing the solvent to obtain the glass fiber reinforced polycaprolactone polymer composite material.
Example 5
(1) Mixing glass fiber and glycolide monomer (the mass ratio of the glass fiber to the monomer is 1:10, adding 500ppm stannous octoate as a catalyst, reacting for 7 hours under the protection of 130 ℃ inert gas, dissolving the product with hexafluoroisopropanol, separating out the glass fiber, precipitating and purifying in ethanol, and drying in vacuum to obtain the polyglycolide surface modified glass fiber.
(2) Mixing the modified glass fiber and polylactide according to the mass ratio of 1:1, and dissolving the mixture in chloroform. And casting the obtained solution into a film, and volatilizing the solvent to obtain the glass fiber reinforced polylactide polymer composite material.
Comparative example 1
Directly mixing the glass fiber and the polylactide according to the mass ratio of 1:5, and dissolving the mixture in chloroform. And casting the obtained solution into a film, and volatilizing the solvent to obtain the glass fiber reinforced polylactide polymer composite material.
Comparative example 2
Polylactide was dissolved in chloroform. And casting the obtained solution to form a film, and volatilizing the solvent to obtain the polylactide polymer material.
Comparative example 3
Directly mixing the glass fiber and the polycaprolactone according to the mass ratio of 1:10, and dissolving in chloroform. And casting the obtained solution into a film, and volatilizing the solvent to obtain the glass fiber reinforced polycaprolactone polymer composite material.
Comparative example 4
Polycaprolactone is dissolved in chloroform. And casting the obtained solution into a film, and volatilizing the solvent to obtain the polycaprolactone polymer material.
Comparative example 5
Directly mixing the glass fiber and the polydioxanone according to the mass ratio of 1:5, and dissolving in hexafluoroisopropanol. And casting the obtained solution into a film, and volatilizing the solvent to obtain the glass fiber reinforced polydioxanone polymer composite material.
Comparative example 6
Polydioxanone is dissolved in hexafluoroisopropanol. And casting the obtained solution to form a film, and volatilizing the solvent to obtain the polydioxanone high polymer material.
Comparative example 7
Directly mixing the glass fiber and the polycaprolactone according to the mass ratio of 1:10, and dissolving in chloroform. And casting the obtained solution into a film, and volatilizing the solvent to obtain the glass fiber reinforced polycaprolactone polymer composite material.
Comparative example 8
Polycaprolactone is dissolved in chloroform. And casting the obtained solution into a film, and volatilizing the solvent to obtain the polycaprolactone polymer material.
Comparative example 9
Directly mixing the glass fiber and the polylactide according to the mass ratio of 1:10, and dissolving the mixture in chloroform. And casting the obtained solution into a film, and volatilizing the solvent to obtain the glass fiber reinforced polylactide polymer composite material.
Comparative example 10
Polylactide was dissolved in chloroform. And casting the obtained solution to form a film, and volatilizing the solvent to obtain the polylactide polymer material.
Analysis of the properties of the specific examples and comparative examples:
according to the experimental data of 1-5 groups, the tensile strength of the polymer composite material prepared by the preparation method of the embodiment of the invention is higher than that of the composite material prepared by the other two groups of comparative examples in the group, which shows that the tensile strength of the polymer composite material prepared by the preparation method of the invention is greatly improved. In addition, the pH values of the polymer composite materials prepared in the examples 1 to 5 after 30 days of degradation are close to neutral, most of the polymer composite materials are alkalescent, and the pH values of the polymer composite materials are basically slightly higher than those of the composite materials prepared in the comparative examples in the group, so that the problem of acidity of degradation products is solved, and the polymer composite materials have good biocompatibility.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (10)
1. A preparation method of a high polymer composite material for enhancing biodegradability is characterized by comprising the following steps:
(1) mixing glass fiber and biodegradable material monomer, and carrying out catalytic reaction, wherein the biodegradable material monomer is at least one of Glycolide (GA), Lactide (LA), p-dioxanone (PDO) and epsilon-Caprolactone (CL);
(2) dissolving the product obtained in the step (1) by using an organic solvent, purifying and drying to obtain modified glass fiber;
(3) mixing the modified glass fiber with a biodegradable high polymer material, dissolving the mixture by an organic solvent, and casting to obtain the high polymer composite material, wherein the biodegradable high polymer material is at least one of polyglycolide, polylactide, polydioxanone, polycaprolactone and copolymers thereof.
2. The preparation method according to claim 1, wherein the mass ratio of the glass fiber to the biodegradable material monomer is 1: 2-20.
3. The method according to claim 1, wherein the catalyst used in the step (1) is stannous octoate in an amount of 50 to 500 ppm.
4. The method according to claim 1, wherein the temperature of the catalytic reaction in the step (1) is 90 to 170 ℃.
5. The preparation method according to claim 4, wherein the catalytic reaction is carried out for 5-72 hours under the protection of vacuum or inert gas.
6. The method according to claim 1, wherein the organic solvent in the step (2) is chloroform, and the purification step is carried out in ethanol.
7. The preparation method according to claim 1, wherein the mass ratio of the modified glass fiber to the biodegradable polymer material in the step (3) is 1:1 to 10.
8. The production method according to claim 1, wherein the organic solvent in the step (3) is chloroform or hexafluoroisopropanol.
9. The method according to claim 1, wherein the solvent is evaporated after the casting in the step (3).
10. A biodegradable reinforced polymer composite prepared by the preparation method according to any one of claims 1 to 9.
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