阅读说明：本技术 含有复合光敏添加剂的降解醋酸纤维在烟滤嘴中的应用 (Application of degraded acetate fiber containing composite photosensitive additive in cigarette filter tip ) 是由 缪建文 宋国华 史珺 吴扬 于 2017-12-20 设计创作，主要内容包括：本发明公开了一种含有复合光敏添加剂的降解醋酸纤维在烟滤嘴中的应用,所述复合光敏添加剂为天然染料提取液和二氧化钛的混合物；天然染料提取液中还添加有碱或酸,所述的碱为NaOH或NaHCO<Sub>3</Sub>,所述的酸为醋酸、硫酸或柠檬酸；所述天然染料提取液的制备方法是：紫草粉末或紫草和紫苏混合粉末与无水乙醇混合,避光静置24h后过滤,得到紫草或紫草和紫苏混合的天然染料提取液。本发明将天然染料提取液与二氧化钛混合,大大增加了可见光区域的吸收,加速了醋酸纤维的降解。(The invention discloses an application of degraded acetate fiber containing a composite photosensitive additive in a cigarette filter tip, wherein the composite photosensitive additive is a mixture of natural dye extracting solution and titanium dioxide; the natural dye extracting solution is also added with alkali or acid, wherein the alkali is NaOH or NaHCO 3 The acid is acetic acid, sulfuric acid or citric acid; the preparation method of the natural dye extracting solution comprises the following steps: mixing radix Arnebiae powder or mixed powder of radix Arnebiae and Perillae herba with anhydrous ethanol, standing in dark for 24 hr, and filtering to obtain natural dye extractive solution of radix Arnebiae or mixed powder of radix Arnebiae and Perillae herba. The inventionThe natural dye extracting solution is mixed with the titanium dioxide, so that the absorption in a visible light area is greatly increased, and the degradation of the acetate fiber is accelerated.)

1. The application of the degraded acetate fiber containing the composite photosensitive additive in the cigarette filter tip is characterized in that: the composite photosensitive additive is a mixture of natural dye extracting solution and titanium dioxide; the natural dye extracting solution is also added with alkali or acid, wherein the alkali is NaOH or NaHCO₃The acid is acetic acid, sulfuric acid or citric acid; the preparation method of the natural dye extracting solution comprises the following steps: mixing radix Arnebiae powder or mixed powder of radix Arnebiae and Perillae herba with anhydrous ethanol, standing in dark for 24 hr, and filtering to obtain natural dye extractive solution of radix Arnebiae or mixed powder of radix Arnebiae and Perillae herba.

2. The use of a degraded acetate fiber containing a composite photosensitive additive in a cigarette filter according to claim 1, wherein: the preparation method of the composite photosensitive additive comprises the following steps:

mixing radix Arnebiae powder or mixed powder of radix Arnebiae and Perillae herba with anhydrous ethanol, standing in dark for 24 hr, and filtering to obtain natural dye extractive solution of radix Arnebiae or mixed powder of radix Arnebiae and Perillae herba;

adding acid solution or alkali solution into the obtained natural dye extractive solution to obtain natural dye extractive solution containing acid or alkali, and adding TiO₂Powder of, is preparedAnd compounding a photosensitive additive.

3. The use of a degraded acetate fiber containing a composite photosensitive additive in a cigarette filter according to claim 2, wherein: the mass ratio of the lithospermum to the perilla is 1: 1-1: 1.5.

4. the use of a degraded acetate fiber containing a composite photosensitive additive in a cigarette filter according to claim 2, wherein: the concentration of the acid solution or the alkali solution is 0.1mol/L, and the addition proportion range is as follows: volume of acid solution or alkali solution: natural dye volume = 1: 4-1: 5.

5. the use of a degraded acetate fiber containing a composite photosensitive additive in a cigarette filter according to claim 2, wherein: mixing the lithospermum powder or the mixed powder of lithospermum and perilla with absolute ethyl alcohol according to the mass-volume ratio of 1: 50-2: mixing at 50 g/mL.

6. The use of a degraded acetate fiber containing a composite photosensitive additive in a cigarette filter according to claim 2, wherein: TiO2₂The mass-volume ratio of the powder to the natural dye extracting solution is 1: 200-1: 250 g/mL.

Technical Field

The invention relates to a composite photosensitive additive for dissolving cellulose acetate, a preparation method and application thereof.

Background

At present, the yield of filter-tipped cigarettes is improved from 6 percent to more than 98 percent, cigarette ends thrown into the environment are gradually increased, the decomposition period is long, and the environment is seriously polluted. The main methods for degrading acetate fibers used to solve this problem at present are as follows:

a chemical method for degrading cellulose acetate

The chemical degradation method is a method for improving the degradation speed of cellulose acetate by adding chemical substances into the cellulose acetate. There are methods of degrading cellulose acetate by adding ester salts and weak acids, and water releases the ester salts and weak acids in the matrix material when the cellulose acetate product is discarded to the environment. The weak acid hydrolyzes the ester salt to release strong acid, and the strong acid further catalyzes the degradation of the acetate fiber tows. However, the organic acids used in this process are not very commonly used because they may be harmful to humans. In addition, polyethylene glycol is added to degrade acetate fibers, but the polyethylene glycol has certain side effects on human bodies, and is not beneficial to human health after long-term use.

B biological method for degrading acetate fiber

The biodegradation method refers to a method for degrading cellulose acetate by using biological soil. Cellulose acetate is decomposed by using microbial components in soil, and if buried under aerobic conditions, its decomposition products are mostly carbon dioxide and water. If oxygen-free, its decomposition products are gases such as carbon monoxide and methane. However, this method has certain limitations, and the number of cigarette butts is enormous throughout the world each day, and it is impossible to completely collect them for burying. This method is not very practical, time and labor consuming to operate, and is inefficient.

C photocatalysis method for degrading acetate fiber

Photocatalysis is a natural phenomenon, substances can be automatically degraded when being placed in the nature, and excessive interference of manpower is not needed. Under the irradiation of ultraviolet light, the molecular weight of the acetate fiber is reduced and the surface area of the acetate fiber is increased, and the cellulose doped in the acetate fiber is irradiated by the ultraviolet light, so that the acetate fiber generates dissociation components to increase the contact force between the acetate fiber and the cellulose fiber, and further the degradation of the acetate fiber is accelerated. However, this method has a problem that ultraviolet rays only account for a small portion of sunlight, and the effect of degrading acetate fibers in a region where visible light is large is not significant, and sunlight cannot be sufficiently utilized.

At present, the most common degradation method for degrading acetate fibers is a novel degradation method combining photocatalysis and biodegradation. Fujishima A studied TiO N-type semiconductors in 1972₂When the electrode is used, the photoelectrocatalysis decomposition function of water is discovered unexpectedly, so that a new era of photocatalysis research is opened up. TiO2₂Is widely used as a semiconductor material. Mainly because of its good stability and low cost, it is not only non-toxic and harmless to human body, but also possesses gas-sensitive, photosensitive and pressure-sensitive and strong photocatalytic property. TiO2₂The photocatalytic mechanism of (a) is: when light irradiates on TiO₂At the surface of the crystal grains, photons with energy larger than or equal to 3.2eV can excite valence band electron-conduction band transition to form electron-hole pairs. With the development of society, the concept of environmental protection is deeply enjoyed, and people hope to find a novel nontoxic and harmless additive for degrading acetate fibers in cigarettes. At present, natural dyes are attracting attention as a novel photocatalytic raw material, mainly because most of the natural dyes are plant dyes, pure natural and non-toxic and harmless. And the extraction method is simple and easy to operate, and does not need to be processed by a chemical method.

Disclosure of Invention

The invention aims to provide a composite photosensitive additive for degrading acetate fibers, which is green and environment-friendly and can effectively degrade the acetate fibers in cigarettes, and a preparation method and application thereof.

The technical solution of the invention is as follows:

a composite photosensitive additive for degrading acetate fibers is characterized in that: is a mixture of natural dye extracting solution and titanium dioxide.

The natural dye extract is radix Arnebiae extract or mixed extract of radix Arnebiae and Perillae herba.

The natural dye extracting solution is also added with alkali or acid, wherein the alkali is NaOH or NaHCO₃The acid is acetic acid, sulfuric acid or citric acid.

The preparation method of the composite photosensitive additive for degrading acetate fibers is characterized by comprising the following steps of: comprises the following steps:

mixing radix Arnebiae powder or mixed powder of radix Arnebiae and Perillae herba with anhydrous ethanol, standing in dark for 24 hr, and filtering to obtain natural dye extractive solution of radix Arnebiae or mixed powder of radix Arnebiae and Perillae herba; adding TiO into the natural dye extracting solution₂Powder to prepare a composite photosensitive additive;

in the step (1), acid or alkali is added into the prepared natural dye extracting solution to obtain the natural dye extracting solution added with the acid or alkali, and TiO is added₂And (5) obtaining the composite photosensitive additive by powder.

The mass ratio of the lithospermum to the perilla is 1: 1-1: 1.5.

the concentration of the acid solution or the alkali solution is 0.1mol/L, and the addition proportion range is as follows: volume of acid solution or alkali solution: natural dye volume = 1: 4-1: 5.

mixing the lithospermum powder or the mixed powder of lithospermum and perilla with absolute ethyl alcohol according to the mass-volume ratio of 1: 50-2: mixing at 50 g/mL.

The mass-volume ratio of the TiO2 powder to the natural dye extracting solution is 1: 200-1: 250 g/mL.

The application of the composite photosensitive additive for degrading acetate fibers is characterized in that: adding the composite photosensitive additive into the cigarette filter.

The invention mixes the natural dye extract with the titanium dioxide, greatly increases the absorption in a visible light area, and accelerates the degradation of the acetate fiber.

The invention uses ultraviolet spectrophotometer to test the absorption peak with the wavelength of 200nm ~ 700nm, absolute ethyl alcohol is used to extract natural dye in the experiment, the absolute ethyl alcohol does not absorb light, so the test result of the experiment can not be influenced₂The prepared composite photosensitizer has the best catalytic degradation effect.

Drawings

The invention is further illustrated by the following figures and examples.

FIG. 1 is a UV-Vis absorption spectrum of TiO 2.

FIG. 2 shows the UV-Vis absorption spectrum of the diluted 50 times solution of radix Arnebiae and Perillae herba.

FIG. 3 shows UV-Vis absorption spectra of radix Arnebiae, Perillae herba and their mixture.

FIG. 4 is a UV-Vis absorption spectrum of a composite natural dye addition acid solution.

FIG. 5 is a UV-Vis absorption spectrum of a composite natural dye additive alkaline solution.

FIG. 6 is a graph of the light weight loss of acetate blank versus added natural dye.

FIG. 7 is a graph of the light weight loss ratio of the acetate blank to the natural dye, TiO 2.

FIG. 8 is a graph of the light weight loss ratio of cellulose acetate + TiO2 with the addition of different natural dyes.

FIG. 9 is a graph of the light weight loss ratio of acetate fibers with addition of natural dyes or with addition of bases or with addition of TiO 2.

FIG. 10 is DSC and TG thermal analysis of acetate + TiO 2.

FIG. 11 is a DSC and TG thermal analysis of cellulose acetate + complex natural dye containing alkali + TiO 2.

FIG. 12 is an SEM image of cellulose acetate + TiO2 after 240h of illumination.

FIG. 13 is an SEM image of cellulose acetate + complex natural dye containing alkali + TiO2 after being irradiated for 240 h.

Detailed Description

(1) Preparation of natural dye:

mixing radix Arnebiae powder or mixed powder of radix Arnebiae and Perillae herba with anhydrous ethanol, standing in dark for 24 hr, and filtering to obtain natural dye extractive solution of radix Arnebiae or mixed powder of radix Arnebiae and Perillae herba; adding TiO into the natural dye extracting solution₂Powder to prepare a composite photosensitive additive;

in the step (1), acid or alkali is added into the prepared natural dye extracting solution to obtain the natural dye extracting solution added with the acid or alkali, and TiO is added₂And (5) obtaining the composite photosensitive additive by powder.

The mass ratio of the lithospermum to the perilla is 1: 1-1: 1.5 (example: 1:1, 1:3, 1: 5).

The concentration of the acid solution or the alkali solution is 0.1mol/L, and the addition proportion range is as follows: volume of acid solution or alkali solution: natural dye volume = 1: 4-1: 5 (example: 1:4, 1: 5).

Mixing the lithospermum powder or the mixed powder of lithospermum and perilla with absolute ethyl alcohol according to the mass-volume ratio of 1: 50-2: 50g/mL (examples 1: 50, 2: 50) were mixed.

The mass-volume ratio of the TiO2 powder to the natural dye extracting solution is 1: 200-1: 250g/mL (examples: 1: 200, 1: 250).

(2) Preparation of model film:

according to the mass-volume ratio of 1: 20-1: dissolving 25g/mL (example: 1: 20, 1: 25) of cellulose acetate in an acetone solution, adding the composite photosensitive additive after the cellulose acetate is fully dissolved, continuously stirring for 5-10min to dissolve the composite photosensitive additive in the previous acetone solution according to the volume ratio of 1:10-1:15, standing for defoaming, and storing in dark place; then pouring the obtained solution on a glass plate, placing the glass plate covered with the model film at a vent, and starting to form the film after 1-2 min.

1. Absorption of light by natural dyes

An ultraviolet-visible spectrophotometer is used for testing an absorption peak with the wavelength of 200nm ~ 700nm, an experiment firstly tests a complete absorption curve of the independent titanium dioxide and the independent purple perilla and lithospermum natural dyes, a maximum absorption peak in a visible light region is tested, and then an absorption peak curve after the natural dyes are overlapped is observed, and figure 1 is an UV-Vis absorption spectrum of TiO 2.

As can be seen from the graph, TiO2 has no absorption in the visible region and has strong absorption in the ultraviolet region. TiO2 absorbs light most strongly at a wavelength of about 350nm, which is a long-wave ultraviolet ray in sunlight. Therefore, only TiO2 is used for degradation, the catalytic degradation of the acetate fiber in the ultraviolet region can be enhanced, the sunlight cannot be completely utilized, and the utilization rate of the visible light region is low.

FIG. 2 shows UV-Vis absorption spectra of radix Arnebiae and Perillae herba solution after dilution by 50 times. As can be seen from the curves in the figure, the lithospermum has a large absorption range, strong absorption in an ultraviolet region and wide absorption in a visible light region, and has a wide application range as a photosensitizer. In addition, the graph also shows that the lithospermum has the strongest absorption peak around 520nm, which is caused by the anthocyanin contained in the lithospermum. The strong absorption peaks at 490nm and 560nm are also attributed to arnebia root, which is a natural dye of naphthoquinone type and contains alkannin. In addition, the curve of perilla showed significant absorption peaks around 430nm and 680nm because perilla contains chlorophyll.

FIG. 3 is a UV-Vis absorption spectrum of radix Arnebiae, Perillae herba and their mixture solution, wherein the mixture solution has distinct absorption peaks at 430nm and 680nm due to chlorophyll contained in Perillae herba, and the mixture solution has 3 absorption peaks similar to radix Arnebiae extract at 500nm ~ 600nm, each peak being higher than its original peak.

As can be seen from FIG. 2 and FIG. 3, the absorption peaks of the extracts of Lithospermum erythrorhizon and Perilla frutescens can be linearly superposed to the highest level, and the absorbance is also the highest. And the composite natural dye extracting solution respectively inherits the maximum absorption peak of the composite natural dye extracting solution to reach the maximum value, and the peaks are not interfered with each other. It was concluded that the composite natural dye of arnebia root and perilla herb has better effect on light absorption than the single natural dye.

2. Absorption of light by composite natural dye with acid or alkali

The composite natural dye is added with 0.1mol/L acetic acid, 0.1mol/L sulfuric acid, 0.1mol/L citric acid, 1mol/L citric acid and blank non-added contrast atlas to obtain figure 4.

It can be seen that the addition of other acids to the natural dye, in addition to sulfuric acid, resulted in a less significant change in the curve, substantially consistent with the curve before addition. However, the set of curves with sulfuric acid added had distinct absorption peaks at 430nm as well as 660nm, with the strongest peaks being higher, the absorption of light becoming stronger, and the absorption peaks blue-shifted at 660 nm. Since sulfuric acid is a strong acid, it is added to the mixed solution to change the structure of organic substances (such as the change of substituents), thereby changing the absorption intensity of the natural dye to light.

FIG. 5 shows a comparison of complex natural dyes with NaHCO3, NaOH, respectively, added to a blank.

After NaHCO3 solution is added into the mixed solution, the absorption peak is obviously enhanced at 420nm, the absorption peak is greatly enhanced at 690nm, and the 3 strongest peaks between 500nm and ~ 600nm do not have the same large enhancement as the former two peaks, so that the absorption band has a tendency of descending and has a red shift phenomenon.

3. Variation of acetate fiber added with composite photosensitive additive under illumination

The cellulose acetate added with different natural dyes (radix Arnebiae extract or radix Arnebiae Perillae herba composite extract or alkali-containing radix Arnebiae Perillae herba composite extract) and cellulose acetate blank degraded under sunlight irradiation, and compared to obtain figure 6.

As can be seen from the figure, the cellulose acetate blank only loses 0.58% of weight after being irradiated for 240 hours, and the speed of photocatalytic degradation of the cellulose acetate blank is very slow. When the natural dye is added, the degradation efficiency of the acetate fiber film is obviously accelerated. The acetate fiber and the lithospermum are degraded by 1.94 percent, the acetate fiber, the lithospermum and the perilla are degraded by 2.02 percent, and the acetate fiber, the lithospermum, the perilla and the alkali are degraded by 2.18 percent.

The cellulose acetate blank is compared with cellulose acetate + TiO2, cellulose acetate + Lithospermum erythrorhizon + TiO2 degradation under sunlight irradiation to obtain figure 7. As can be seen from the curve in the figure, the cellulose acetate is degraded by 3.16% after being added with TiO2, the degradation is obvious compared with that of the blank and only added with natural dye, and the degradation rate of the cellulose acetate when being added with lithospermum and TiO2 is 3.96%. Indicating that TiO2 or the natural dye alone does not degrade as much as TiO2 does with the natural dye when used as a photosensitizer.

FIG. 8 shows the comparative curves of the degradation effect of TiO2 mixed with different natural dyes (radix Arnebiae extract, radix Arnebiae Perillae herba composite extract or alkali-containing radix Arnebiae Perillae herba composite extract) added into cellulose acetate and cellulose acetate blank. It can be seen that the degradation speed of the acetate fiber, the lithospermum, the perilla, the alkali and the TiO2 is the fastest and the most effective, and the weight loss is 4.37 percent after 240 hours of illumination. Fig. 7 and 8 are all graphs compared to fig. 9.

It can be clearly seen from fig. 9 that the cellulose acetate film without the addition has a poor degradation effect, the degradation is faster after the addition of the natural dye, but the degradation is slower than the degradation only by the addition of the TiO2, so that the TiO2 plays an important role in the degradation, the TiO2 can be adsorbed on the surface of the organic matter to generate oxidation reaction so as to generate water and carbon dioxide, the photocatalytic degradation of the cellulose acetate is accelerated, and the weight loss ratio of the cellulose acetate is obviously greater than the weight loss ratio of the cellulose acetate due to the photo-oxidation. In addition, TiO2 only absorbs in the ultraviolet region, and after the natural dye is doped, the light absorption range of the photocatalyst becomes wider, so that the cellulose acetate is degraded more obviously, and therefore the scheme that the cellulose acetate is added with the alkali-containing composite natural dye extracting solution and mixed with TiO2 has the best degradation effect on the cellulose acetate.

FIGS. 10 and 11 show the differential thermal analysis of cellulose acetate + TiO2 after illumination, and the differential thermal analysis of cellulose acetate + alkali-containing complex natural dye + TiO2 after illumination, respectively. It can be seen from the figure that the quality of the acetate fiber hardly changes in the range of 50 ℃ to 300 ℃, and the quality of the acetate fiber decreases sharply in the interval from 300 ℃ to 400 ℃, which is probably due to the decomposition of the acetate fiber. The absorption peak is about 55 ℃, and the absorption peak is the absorption peak of the acetone solvent which is not completely volatilized at 229.88 ℃, and the absorption peak is formed by the dissolution of the acetate fiber. FIG. 11 shows the same endothermic peak at 55 ℃ but the other endothermic peak at 228.01 ℃ is 1.87 ℃ lower than that of cellulose acetate with TiO2, which shows that the temperature at which the cellulose acetate is melted is lower after the addition of natural dye. Comparing with the mass change curve in fig. 10 and fig. 11, it is found that the mass of the acetate fiber added with TiO2 is reduced by 29.47%, while the mass of the acetate fiber added with shikonin extract, perilla extract, alkali and TiO2 is reduced by 34.65%, thereby illustrating that the degradation of the acetate fiber is accelerated by adding the alkali-containing complex natural dye.

Meanwhile, in the experiment, the solution of the acetate fibers added with different substances after being irradiated for 240 hours under the illumination is also characterized by a scanning electron microscope. FIG. 11 is an electron micrograph of cellulose acetate + TiO2 after 240 hours of irradiation with light. A is an electron micrograph magnified 1000 times showing fine black spots, but not clearly, white particles may be uniformly undoped TiO2 powder. And B is a graph amplified by 10000 times, black spots in the graph are more obvious, and presumably the acetate fiber membrane participates in degradation, so that the thickness of the membrane is different, and the black spots are thinner parts after degradation.

FIG. 12 shows an electron micrograph of cellulose acetate + alkali-containing complex natural dye + TiO2 after being irradiated for 240 hours. The large-area obvious cavities fully indicate that the acetate fiber membrane is degraded, and the degradation effect is obvious. In fig. 13, D is a graph enlarged by 10000 times, in which a plurality of irregular circular holes with large diameters are formed, and a plurality of holes with different sizes are distributed around the circular holes, so as to more clearly show the morphology of the degraded cellulose acetate film, which indicates that the composite photosensitizer added with the alkali-containing composite natural dye and the TiO2 has an obvious effect on the degradation of cellulose acetate.

Conclusion

(1) After the lithospermum and perilla natural dye used by the invention is mixed, the absorption performance of the lithospermum and perilla natural dye does not interfere with each other, the absorption peaks can be linearly superposed, and the absorption intensity is increased.

(2) The compound photosensitive additive prepared by the invention can change the original material structure by adding the alkali into the lithospermum and perilla mixed natural dye, so that the absorption peak generates red shift, the intensity of the absorption peak is increased, and the absorption of visible light is enhanced.

(3) The natural dye is added into the acetate fiber only to help the photodegradation of the acetate fiber. The addition of TiO2 alone also contributes to the degradation of the acetate fibers and is more effective than the addition of natural dyes alone. When natural dye and TiO2 are added at the same time, the degradation effect of the acetate fiber is the most obvious, the specific scheme is that alkali is added into the composite natural dye extract of the lithospermum and the perilla, and then TiO2 is mixed to prepare the composite photosensitizer, and the method has the best effect of catalyzing and degrading the acetate fiber.