阅读说明：本技术 一种抗紫外纳米木质素复合膜及其制备方法 (Anti-ultraviolet nano lignin composite membrane and preparation method thereof ) 是由 张智亮 居挺 李扬 缪鑫峰 于 2019-09-29 设计创作，主要内容包括：本发明公开了一种抗紫外纳米木质素复合膜及其制备方法,该复合膜由纳米木质素复合颗粒和高分子聚合物载体组成,其中,纳米木质素复合颗粒与高分子聚合物载体质量比为1:100-800。本发明制备的复合膜具有抗紫外性能,而且生物相容性好。从扫描电子显微镜中可以看出,纳米复合颗粒在复合膜中分散均匀；经紫外吸收检测证实,复合膜紫外吸收稳定性强,在可见光波段有较好的透过率,在紫外波段可实现紫外吸收,具有很好的实用性。(The invention discloses an anti-ultraviolet nano lignin composite membrane and a preparation method thereof, wherein the composite membrane consists of nano lignin composite particles and a high molecular polymer carrier, wherein the mass ratio of the nano lignin composite particles to the high molecular polymer carrier is 1: 100-800. The composite membrane prepared by the invention has uvioresistant performance and good biocompatibility. As can be seen from the scanning electron microscope, the nano composite particles are uniformly dispersed in the composite film; ultraviolet absorption detection proves that the composite film has strong ultraviolet absorption stability, better transmittance in a visible light wave band, ultraviolet absorption in the ultraviolet wave band and good practicability.)

1. An uvioresistant nano lignin composite membrane is characterized in that: the composite membrane consists of nano lignin composite particles and a high molecular polymer carrier, wherein the mass ratio of the nano lignin composite particles to the high molecular polymer carrier is 1: 100-800.

2. the ultraviolet-resistant nano lignin composite membrane according to claim 1, wherein: the nano lignin composite particles consist of nano lignin, a surfactant and a polymer, wherein the surfactant is one or a mixture of sodium dodecyl sulfate, disodium lauryl sulfosuccinate, disodium cocomonoethanolamide sulfosuccinate, monolauryl phosphate and lauramidopropyl betaine; the polymer is one or a mixture of more of polyvinylpyrrolidone, polyacrylamide, polyethylene glycol, polyvinyl alcohol and polyethylene oxide; the concentration of the nano lignin in the nano lignin particles is 0.1-1.0 wt%, and the mass ratio of the surfactant to the polymer is 1: 10-100.

3. the ultraviolet-resistant nano lignin composite membrane according to claim 1, wherein: the high molecular polymer is one or a mixture of more of polyacrylamide, polyvinyl alcohol, polyethyleneimine, polyethylene oxide and polyethylene glycol.

4. a preparation method of the ultraviolet-resistant nano lignin composite membrane according to claim 1 is characterized in that: comprises the following steps:

1) Adding a water-soluble high molecular polymer into water, heating, and uniformly stirring to obtain a high molecular polymer solution;

2) adding the nano lignin composite particles into a high molecular polymer solution, uniformly stirring to obtain a composite membrane solution, and placing the composite membrane solution in a water bath for sealing and ultrasonic dispersion to be uniform;

3) And (3) placing the composite membrane solution obtained in the step 2) in a horizontally placed polytetrafluoroethylene membrane forming vessel, carrying out vacuum defoamation in a vacuum drying oven, and drying in the oven to obtain the uvioresistant nano lignin composite particle polymer composite membrane.

5. the method of claim 4, wherein: the method comprises the following steps:

1) Stirring a high molecular polymer solution with the concentration of 1-100 g/L for 1-4 h at the stirring speed of 100-1000 rpm at the temperature of 60-100 ℃;

2) adding the nano lignin composite particles into a high molecular polymer solution according to the condition that the mass ratio of the nano lignin composite particles to the high molecular polymer is 1: 40-200, stirring for 1-4 hours at the stirring speed of 300-1200 rpm to obtain a composite membrane solution, placing the composite membrane solution into a water bath, performing ultrasonic treatment for 10-30 min at the power of 100-300W, and uniformly dispersing;

3) Placing the composite membrane solution obtained in the step 2) in a horizontally placed polytetrafluoroethylene membrane forming vessel, carrying out vacuum defoamation for 4-20 h in a vacuum drying oven, and drying for 12-24 h at a drying temperature of 30-90 ℃ to obtain the anti-ultraviolet nano lignin composite membrane.

Technical Field

the invention relates to an anti-ultraviolet nano lignin composite membrane and a preparation method thereof, belonging to the technical field of nano composite membranes.

Background

In recent years, with the deterioration of ecological environment, especially the destruction of ozone layer, the ultraviolet radiation of earth surface is enhanced. Excessive ultraviolet radiation can cause many hazards to people's health, such as sunburn of the skin, which can seriously lead to skin cancer; ultraviolet radiation can also cause aging, food spoilage, and the like of certain materials. Therefore, the ultraviolet-resistant material has wide application prospect.

For the purpose of ultraviolet radiation resistance, it is often chosen to add some ultraviolet absorber to the matrix material. Ultraviolet absorbers are currently widely used light stabilizers, and can be classified into salicylates, benzophenones, benzotriazoles, substituted acrylonitriles, triazines, and the like according to the structure. However, these ultraviolet absorbers have poor stability and their ultraviolet resistance cannot be maintained, which limits their use. And some inorganic nano materials such as ZnO and TiO₂Can also be used as an anti-ultraviolet absorbent and has good stability. However, the inorganic nano material is not easy to degrade and can remain in the environment to cause secondary pollution. And the photocatalytic action of the inorganic nano material under ultraviolet radiation can cause the degradation of some high polymer matrix materials and destroy the material structure.

lignin has the advantages of biodegradability, renewability, richness, low cost and the like, and is considered as a functional filler and a reinforcing agent of various polymers. Aromatic ring, phenolic hydroxyl, carbonyl and other functional groups in the lignin have good ultraviolet absorption capacity. In addition, the lignin nanoparticles have good compatibility with the polymer matrix, and can enhance various polymers even if the filling amount is small. The ultraviolet resistance of the nano lignin composite particles can be effectively enhanced by doping the nano lignin composite particles into a high-molecular base material, so that the novel ultraviolet-resistant nano composite material with good biodegradability is obtained.

At present, a large number of patent documents report ultraviolet resistant composite films and preparation methods thereof. For example, chinese patent CN109021473A discloses a highly transparent ultraviolet-proof nano cellulose composite film and a preparation method thereof, wherein modified cellulose nano fibers are mixed with a polyvinyl alcohol aqueous solution according to a certain mass ratio, and the mixture is dried in an oven to obtain the composite film. Although the surface modification method can improve the compatibility of the cellulose and the polyvinyl alcohol, the modification method has more complicated steps, needs a large amount of organic solvents and reagents in the modification process, and is difficult to remove in the subsequent film making process to influence the performance of the composite film. In chinese patent CN 101585925a, the inventor mixes a zinc oxide nanocrystal solution with a high molecular polymer solution, and evaporates to remove the organic solvent to obtain a ZnO-high molecular composite film with anti-ultraviolet properties. Although the obtained ZnO-polymer composite film has better ultraviolet resistance effect, ZnO in the ZnO-polymer composite film is not easy to degrade and is easy to cause secondary pollution. Aiming at the defects in the patents, the biodegradable nano lignin is prepared into a green ultraviolet-resistant composite film by a simple coating film-making method without surface modification or organic solvent, so that a new way is provided for developing a new ultraviolet-resistant composite material.

Disclosure of Invention

The invention aims to provide an anti-ultraviolet nano lignin composite film and a preparation method thereof. The preparation process mainly comprises the steps of mixing the nano lignin composite particles with an aqueous solution of a water-soluble high-molecular polymer, coating the mixture to form a film and drying the film to prepare the anti-ultraviolet nano lignin composite film. The preparation method has the advantages of simple steps, simple and convenient operation and the like.

In order to achieve the purpose, the technical scheme of the invention is as follows:

An uvioresistant nano lignin composite membrane is characterized in that: the composite membrane consists of nano lignin composite particles and a high molecular polymer carrier, wherein the mass ratio of the nano lignin composite particles to the high molecular polymer carrier is 1: 100-800.

the nano lignin composite particle consists of nano lignin, a surfactant and a macromolecule, wherein the surfactant is one or a mixture of more of sodium dodecyl sulfate, disodium lauryl sulfosuccinate, disodium cocomonoethanolamide sulfosuccinate, monolauryl phosphate and lauramidopropyl betaine, and the macromolecule is one or a mixture of more of polyvinylpyrrolidone, polyacrylamide, polyethylene glycol, polyvinyl alcohol and polyethylene oxide. The concentration of the nano lignin in the nano lignin composite particles is 0.1-1.0 wt%, and the mass ratio of the surfactant to the high polymer is 1: 10-100.

the water-soluble high molecular polymer is one or a mixture of several of polyacrylamide, polyvinyl alcohol, polyethyleneimine, polyethylene oxide and polyethylene glycol.

The ultraviolet-resistant nano lignin composite membrane is prepared by adding nano lignin composite particles into a high-molecular aqueous solution and then coating and drying the nano lignin composite particles, and specifically comprises the following steps:

1) Adding a certain amount of water-soluble high molecular polymer into a certain amount of water, heating at a specific temperature, and uniformly stirring to obtain a high molecular polymer solution with a certain concentration;

2) Adding a certain amount of nano lignin composite particles into a high molecular polymer solution, uniformly stirring at a certain stirring speed to obtain a nano lignin composite film solution with a certain concentration, and ultrasonically dispersing in a water bath;

3) And (3) placing a certain amount of the composite membrane solution in a horizontally placed polytetrafluoroethylene membrane forming vessel, performing vacuum defoamation in a vacuum drying oven, and drying in the oven to obtain the ultraviolet-resistant nano lignin composite membrane.

Further, in the step 1), the heating temperature is 60-100 ℃, the stirring speed is 100-1000 rpm, and the stirring time is 1-4 hours.

Further, in the step 1, the mass concentration of the high molecular polymer solution is 1-100 g/L.

Further, in the step 2, the stirring speed is 300-1200 rpm, the stirring time is 1-4 hours, the water bath ultrasonic power is 100-300W, and the ultrasonic time is 10-30 min.

Further, in the step 2, the mass ratio of the nano lignin composite particles to the high molecular polymer in the composite membrane solution is 1: 40-200.

further, in the step 3, the vacuum defoaming time is 4-20 hours, the drying temperature of the oven is 30-90 ℃, and the drying time is 12-24 hours.

Compared with the prior art, the invention has the beneficial effects that: advantageous effects the advantages of the composite film should be said first, and then the advantages of the method should be said

1. the composite membrane prepared by the invention has uvioresistant performance and good biocompatibility. It can be seen from the scanning electron microscope that the nanocomposite particles are uniformly dispersed in the composite film.

2. ultraviolet absorption detection proves that the composite film has strong ultraviolet absorption stability, better transmittance in a visible light wave band, ultraviolet absorption in the ultraviolet wave band and good practicability.

3. The invention adopts a coating film-making method with simple operation, simple and convenient steps and low cost. The lignin nano composite particle has the ultraviolet resistance, and is prepared from lignin which is biodegradable, good in stability, low in price and rich in source.

Drawings

The following detailed description is made with reference to the accompanying drawings and embodiments of the present invention

FIG. 1 is a diagram of the UV absorption spectrum of the UV resistant nano lignin composite particle polymer composite membrane under the conditions of example 2.

Detailed Description

The present invention is further illustrated by the following specific examples, but the scope of the invention is not limited thereto.