阅读说明：本技术 一种组合物的制备方法 (Preparation method of composition ) 是由 张秀成 李颖 王思雨 鱼展瑜 于 2019-03-22 设计创作，主要内容包括：本发明涉及一种组合物的制备方法,该组合物包含壳聚糖、纳米羟基磷灰石、聚乙烯吡咯烷酮、聚乳酸。以棒状不溶性钙盐为模板,使其与壳聚糖溶液进行交联。碱性条件下加入磷酸盐溶液,在钙离子/壳聚糖成核位点处生成交叉的纳米线状羟基磷灰石与壳聚糖复合物。利用PVP的网状结构,PLA作为支撑体构建网状框架,使复合物均匀地置于其中。由于其特有的在位点处形成的纳米线状复合物,又在网状框架下形成相互嵌合的网状结构,大大增加了其表面积,增强了其力学性能,成为了一种具有优良吸附性且力学性能良好的壳聚糖(CS)-纳米羟基磷灰石(nHA)-聚乙烯吡咯烷酮(PVP)-聚乳酸(PLA)组合物。可以吸附金属离子,因此在水污染处理方面有广阔的应用前景。(The invention relates to a preparation method of a composition, which comprises chitosan, nano-hydroxyapatite, polyvinylpyrrolidone and polylactic acid. Using rod-shaped insoluble calcium salt as a template, and crosslinking the rod-shaped insoluble calcium salt with the chitosan solution. Adding phosphate solution under alkaline condition to generate crossed nano linear hydroxyapatite and chitosan compound at the calcium ion/chitosan nucleation site. With the network structure of PVP, PLA is used as a support to construct a network framework into which the composite is uniformly placed. The specific nano linear compound formed at the site forms a mutually embedded reticular structure under the reticular framework, so that the surface area of the composition is greatly increased, the mechanical property of the composition is enhanced, and the composition becomes a Chitosan (CS) -nano hydroxyapatite (nHA) -polyvinylpyrrolidone (PVP) -polylactic acid (PLA) composition with excellent adsorbability and good mechanical property. Can adsorb metal ions, thereby having wide application prospect in the aspect of water pollution treatment.)

1. The preparation method of the composition is characterized by comprising chitosan, nano hydroxyapatite, polyvinylpyrrolidone and polylactic acid. The cross embedding structure of the nano-hydroxyapatite and the chitosan is regularly embedded in the insoluble calcium salt template to form a three-dimensional structure which takes the calcium salt as the center and regularly disperses around in a cross line shape. Placing the mixture into a network framework formed by polyvinylpyrrolidone and polylactic acid to form a network structure in which CS-nHA and PVP-PLA are mutually embedded, and obtaining the CS-nHA-PVP-PLA composition.

2. The method of claim 1, wherein the insoluble calcium salt in rod form is selected from the group consisting of calcium carbonate, calcium sulfate, calcium sulfite, calcium phosphate, and calcium silicate.

3. The method of claim 1, wherein the mass ratio of chitosan to hydroxyapatite is 0.5: 9.5-5:5.

4. A method of preparing a CS-nHA-PVP-PLA composition as claimed in claim 1, comprising the steps of:

(1) the solid calcium salt is prepared by using soluble sodium salt and soluble calcium salt, and citric acid, PSS, rosinyl gemini and the like can be used as a surfactant.

(2) Dissolving chitosan in acetic acid, placing the solid calcium salt prepared in the step (1) in the acetic acid, and crosslinking at a certain temperature to obtain mixed slurry with calcium ions/chitosan sites on the solid calcium salt.

(3) And (3) adjusting the pH of the slurry obtained in the step (2) to be about 12, adding phosphate solution with the pH of about 10, and obtaining the embedded hydroxyapatite-chitosan crossed nanowire compound by using a solid calcium salt as a template through an in-situ precipitation method.

(4) PVP was dissolved in water and PLA was dissolved in dichloromethane, both of which were mixed to form a gel.

(5) And (4) crosslinking the compound obtained in the step (3) and the gel obtained in the step (4) to obtain the CS-nHA-PVP-PLA composition.

5. The method of claim 3, wherein the phosphate solution of step (2) is selected from the group consisting of sodium phosphate, potassium phosphate, ammonium monohydrogen phosphate, and ammonium dihydrogen phosphate.

6. The method of claim 3, wherein the chitosan solution has a mass fraction of 2%.

7. The method for preparing a CS-nHA-PVP-PLA composition according to claim 3, wherein in step (3): the reaction temperature is 50-150 ℃ and the reaction time is 2-12 hours; precipitating the obtained slurry for 24-48 hours, and washing the slurry to be neutral by deionized water; the drying time of the obtained compound is 24-72 hours.

8. The method of claim 3, wherein the PVP in step (4) is PVP: PLA: the ratio of CS is 1: 1: 5.

9. the method of claim 3, wherein the PVP and PLA are gelled at a temperature of 25-35 ℃ in step (4), and the reaction time is 1-5 hours.

10. The method of claim 3, wherein in step (5): the crosslinking temperature is 25-35 ℃, and the crosslinking time is 2-8 hours; the resulting composition has a drying time of 24 to 72 hours.

Technical Field

The invention relates to the fields of high polymer materials, inorganic ceramics and nano composite materials, in particular to a preparation method of a Chitosan (CS) -nano hydroxyapatite (nHA) -polyvinylpyrrolidone (PVP) -polylactic acid (PLA) composition.

Background

Hydroxyapatite is a main inorganic component in bones and has good biological activity, biocompatibility and bone conduction performance, so the hydroxyapatite is widely applied to the biomedical field, such as drug delivery and bone tissue repair, but is limited in the application process due to the defects of brittle property, lack of plasticity and low mechanical strength.

The chitosan is a natural polymer, has good biocompatibility, biodegradability and adsorption capacity, and is a good bone repair material. The chitosan can form a composite material with various substances, and the biocompatibility and other properties of the chitosan are improved, so that the chitosan can be widely applied to the field of biomedicine. The hydroxyapatite biological composite material is compounded by hydroxyapatite and natural high molecular compounds, and the mechanical property of the composite material formed by chitosan and hydroxyapatite is greatly improved. The specific nano linear compound formed at the site has a large specific surface area and can adsorb metal ions, so that the nano linear compound has a wide application prospect in the aspect of sewage treatment.

Polyvinylpyrrolidone is a non-ionic polymer compound, has excellent solubility and chemical stability, and can be complexed with various substances. Polylactic acid is a reproducible bio-based polymer, has good biocompatibility and degradability, but has poor hydrophilicity and lower mechanical strength. The network structure of PVP is utilized to be crosslinked with PLA, so that the mechanical property of the compound can be improved.

Disclosure of Invention

The invention aims to provide a preparation method of a CS-nHA-PVP-PLA composition.

The innovation of the invention is that when the content of chitosan is small, the compound structure is a cross-linear nano hydroxyapatite-chitosan compound generated at a calcium ion/chitosan site. The size of the linear hydroxyapatite is about tens to hundreds of nanometers, and the size of the compound is about several micrometers.

The innovation of the invention is that when the chitosan content is larger, the compound structure is that linear nano hydroxyapatite coated by chitosan is generated at calcium ion/chitosan sites. The coated linear hydroxyapatite is about tens to hundreds of nanometers in size, and the composite is about several microns in size.

The innovation of the invention is that a network framework is constructed by utilizing a net structure of PVP and PLA as a support body, and the CS-nHA compound is uniformly embedded in the network framework to form the CS-nHA-PVP-PLA net composition.

The technical scheme of the invention is as follows:

a preparation method of a CS-nHA-PVP-PLA composition comprises the following steps:

(1) method for preparing mosaic type hydroxyapatite-chitosan crossed nanowire compound by using rod-shaped insoluble calcium salt as template

0.04mol of rod-shaped insoluble calcium salt is put into a solution containing 0.21g to 4.00g of chitosan by mass, and crosslinking is carried out at 80 ℃ to obtain mixed slurry with calcium ions/chitosan sites on the solid calcium salt, and the mixed slurry is adjusted to pH of about 12 by ammonia water. 0.024mol of phosphate is taken to prepare a solution, ammonia water is used for adjusting the PH value to be about 10, the solution is added into the mixed slurry, and the total PH value is kept above 10 in the reaction process. Reacting at 80 ℃ for 8 hours, aging at room temperature for 24 hours, washing with deionized water to be neutral, and drying to obtain the hydroxyapatite-chitosan compound with the cross structure.

(2) Preparation of CS-nHA-PVP-PLA composition

0.04g to 0.8g of PVP was dissolved in water, and 0.04g to 0.8g of PLA was dissolved in methylene chloride, and both were crosslinked at room temperature to obtain a gel. Adding CS-nHA into the gel, and reacting at room temperature to obtain a chimeric CS-nHA-PVP-PL composition.

The chitosan solution is 2% acetic acid solution, and a certain amount of chitosan is dissolved in the acetic acid solution, and the mass fraction of the chitosan solution is 2%.

The crosslinking time is 2 hours, and the crosslinking temperature is 80 ℃.

The preparation time of the CS-nHA is 8 hours, and the preparation temperature is 80 ℃.

The hydroxyapatite preparation comprises the following raw materials in proportion: calcium to phosphorus ratio was 1.67: 1.

the mass ratio of chitosan to hydroxyapatite in the prepared CS-nHA is 0.5:9.5-5: 5.

The aging time for preparing the CS-nHA is 24 hours, and the aging temperature is room temperature.

The drying time for preparing CS-nHA is 24 hours, and the drying temperature is 105 ℃.

The preparation composition has PVP: PLA: the ratio of CS is 1: 1: 5.

the temperature for forming gel by PVP and PLA in the prepared composition is 25-35 ℃, and the reaction time is 1-5 hours.

The crosslinking temperature of the gel and the CS-nHA in the prepared composition is 25-35 ℃, and the crosslinking time is 2-8 hours.

The drying time for preparing the composition is 24-72 hours.

Detailed Description

A preparation method of a CS-nHA-PVP-PLA composition comprises the following steps: