Natural polysaccharide aerogel for cigarettes

Abstract

The invention belongs to the technical field of treatment of harmful substances in cigarettes, and particularly relates to natural polysaccharide aerogel for cigarettes. The preparation method comprises the following steps: S1, dispersing the polysaccharide, the filler and the cross-linking agent in a solvent, and stirring by using a stirrer until the materials are completely dissolved; s2, adding a hydrophobic modifier, an ion exchange modifier, a surfactant and a functional polymer into the polysaccharide solution, and performing stirring reaction by using a heating stirrer to obtain a modified solution; s3, cooling the modified solution to room temperature by using cooling equipment, then pouring the solution into a mold for gelation, then putting the solution into freezing equipment, and cooling the solution until the solution is completely frozen to obtain frozen gel; and S4, transferring the frozen gel into a freeze dryer, and carrying out sublimation drying under a vacuum condition to obtain the natural polysaccharide aerogel. The natural polysaccharide aerogel prepared by the invention can remarkably improve the filtering performance of a filter tip, so that the content of tar and other harmful substances generated in the smoking process can be reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of treatment of harmful substances in cigarettes, and particularly relates to a natural polysaccharide aerogel for cigarettes. Background Art

[0002] The waste generated by tobacco combustion is a complex mixture of various chemical substances, which pose significant health hazards to smokers and the surrounding environment. These wastes mainly include gaseous and solid components, and among them, the tar in the solid components is particularly harmful to the human body. Tar is a viscous black substance containing various carcinogens, and its deposition in the lungs can cause lung cancer, laryngeal cancer and other respiratory diseases. Therefore, how to efficiently reduce tar and harm is an urgent problem to be solved in the tobacco field.

[0003] Natural polysaccharide aerogel is a new type of nanomaterial with advantages such as high porosity, low density and good biocompatibility, and shows broad application prospects in many fields including tobacco tar reduction and harm reduction. Natural polysaccharide aerogel has a highly porous three-dimensional network structure, which provides a large surface area. And natural polysaccharide aerogel has good biocompatibility and no toxic and side effects on the human body. As a tobacco filter material or additive, its safety is higher and no new health problems will be generated.

[0004] However, the tar generated by tobacco combustion contains hundreds of different compounds, and the complexity and diversity of tar make it difficult for existing natural polysaccharide aerogels to specifically remove it.

[0005] In summary, there is a need for a natural polysaccharide aerogel that can efficiently reduce tar at present. Summary of the Invention

[0006] The purpose of the present invention is to provide a preparation method of a natural polysaccharide aerogel for cigarettes. The natural polysaccharide aerogel prepared by the present invention can significantly improve the filtration performance of the filter tip, thereby helping to reduce the content of tar and other harmful substances generated during smoking.

[0007] The technical solution adopted by the present invention to solve the above problems is: a preparation method of a natural polysaccharide aerogel for cigarettes, comprising the following steps: S1. Disperse 100-200 parts of polysaccharide, 1-5 parts of filler, and 1-5 parts of crosslinking agent by weight in 50-100 parts of solvent, and use a stirrer to stir until completely dissolved to form a uniform polysaccharide solution; S2. Add 5-10 parts of hydrophobic modifier, 5-10 parts of ion exchange modifier, 5-10 parts of surfactant, and 3-5 parts of functional polymer by weight to the polysaccharide solution, and continuously stir and react at 60-80 °C for 2-4 h using a heating stirrer to obtain a modified solution; S3. Cool the modified solution to room temperature using a cooling device, then pour it into a mold for gelation, and then place it in a freezing device, cool it to -20 °C or below and -40 °C or above, and keep it for 1 - 2 h until it is completely frozen to obtain a frozen gel; S4. Transfer the frozen gel to a freeze dryer and perform sublimation drying under vacuum conditions to obtain a natural polysaccharide aerogel.

[0008] Among them, the component classification in tar can be divided into hydrophobic components and polar components.

[0009] Hydrophobic components include polycyclic aromatic hydrocarbons (PAHs): These compounds are composed of multiple benzene rings and have strong hydrophobicity. PAHs are one of the main carcinogens in tar; Aromatic hydrocarbons: In addition to PAHs, there are some other aromatic hydrocarbon compounds, which also have hydrophobicity; Long-chain aliphatic hydrocarbons: These compounds are composed of long-chain hydrocarbon compounds and have strong hydrophobicity.

[0010] Polar components include phenolic compounds: These compounds contain a hydroxyl (-OH) group and have certain polarity; Aldehydes and ketones: These compounds contain a carbonyl (-C=O) group and have certain polarity; Nitrogen-containing compounds: Such as nitrosamines, pyridine, etc., also have certain polarity; Add a hydrophobic modifier to the natural polysaccharide aerogel to enhance the adsorption capacity for organic substances, especially improve the adsorption effect on hydrophobic substances in tar. At the same time, an ion exchange modifier is also added to the natural polysaccharide aerogel, which can further adsorb the polar components in tar, greatly improving the adsorption capacity of the natural polysaccharide aerogel for tar.

[0011] In particular, the hydrophobic modifier and the ion exchange modifier have different polarities, so they can be well distributed in the natural polysaccharide aerogel to jointly adsorb the tar generated by tobacco combustion.

[0012] A further preferred technical solution is that: the hydrophobic modifier includes one of methyltriethoxysilane, ethyltriethoxysilane, methyltrimethoxysilane, and phenyltriethoxysilane.

[0013] A further preferred technical solution is that: the ion exchange modifier includes one of 3-(triethoxysilyl)propane sulfonic acid and 3-(trimethoxysilyl)propane sulfonic acid.

[0014] A further preferred technical solution is that: the surfactant includes one of octyltriethoxysilane, trifluoropropyltriethoxysilane, sodium dodecyl sulfate, and sodium laureth sulfate.

[0015] A further preferred technical solution lies in that: the functional polymer includes one of polyethyleneimine and polyacrylic acid.

[0016] A further preferred technical solution lies in that: the filler includes one of calcium carbonate, barium carbonate and barium sulfate.

[0017] A further preferred technical solution lies in that: the crosslinking agent includes one of glutaraldehyde and ethylene glycol diglycidyl ether.

[0018] A further preferred technical solution lies in that: the solvent includes one or a mixture composed of one or more of water, ethanol and methanol.

[0019] A further preferred technical solution lies in that: the dispersion method is ultrasonic dispersion using an ultrasonic disperser with a power of 150 - 350 W.

[0020] A further preferred technical solution lies in that: the polysaccharide includes one of cellulose, chitosan, sodium alginate, agar, starch and pectin.

[0021] A further preferred technical solution lies in that: in step S1, the pH value of the solution is 6.5 - 7.5.

[0022] In summary, the present invention has the following beneficial effects: 1. Adding a hydrophobic modifier to the natural polysaccharide aerogel can improve the adsorption and filtration effect on the hydrophobic components in tar. At the same time, an ion exchange modifier is also provided in the natural polysaccharide aerogel to further improve the adsorption and filtration effect on the polar components in tar, thereby overall improving the tar reduction effect of the filter tip.

[0023] 2. The natural polysaccharide aerogel itself can also significantly improve the filtration performance of the filter tip, thereby helping to reduce the content of tar and other harmful substances generated during smoking. Detailed Embodiments

[0024] The following further elaborates on the present invention. The sources of the raw materials mentioned in the examples and comparative examples are as follows: Cellulose: Model: Avicel PH - 101 Manufacturer: FMC Corporation Chitosan: Model: Chitosan 95% deacetylation Manufacturer: Sigma - Aldrich Sodium alginate: Model: Protanal LF 10 / 60 FT Manufacturer: FMC BioPolymer Agar: Model: Agarose LE Manufacturer: Lonza Starch: Model: CERES® 2000 Manufacturer: Cargill Methyltriethoxysilane: Model: Dynasylan® MTES Manufacturer: Evonik Ethyltriethoxysilane: Model: Triethoxyethylsilane Manufacturer: ABCR GmbH Methyltrimethoxysilane: Model: Silquest A-1630 Manufacturer: Momentive Phenyltriethoxysilane: Model: Sipex® PHES Manufacturer: Wacker Chemie AG 3-(Triethoxysilyl)propanesulfonic acid: Model: Dynasylan® SIVO 214 Manufacturer: Evonik 3-(Trimethoxysilyl)propanesulfonic acid: Model: Sipex® MPS Manufacturer: Wacker Chemie AG Octyltriethoxysilane: Model: Dynasylan® OCTEO Manufacturer: Evonik Trifluoropropyltriethoxysilane: Model: 3,3,3-Trifluoropropyltriethoxysilane Manufacturer: Gelest Inc. Sodium dodecyl sulfate: Model: SDS (Sodium Dodecyl Sulfate) Extra Pure Manufacturer: Merck (Sigma-Aldrich) Sodium laureth sulfate: Model: Texapon N70 Manufacturer: BASF Polyethyleneimine (PEI): Model: PEI 25k (Branched, MW 25,000) Manufacturer: Polysciences, Inc. Polyacrylic Acid (PAA): Model: Carbopol® 940 Manufacturer: Lubrizol Calcium Carbonate (CaCO3): Model: OMYA BLR2 Manufacturer: Omya AG Barium Carbonate (BaCO3): Model: ShinkoLite BC-1500 Manufacturer: Shinko Chemical Co., Ltd. Barium Sulfate (BaSO4): Model: Blanc Fixe N Manufacturer: Sachtleben Chemie GmbH Glutaraldehyde: Model: Glutaraldehyde Solution, 50% Manufacturer: Sigma-Aldrich (Merck) Ethylene Glycol Diglycidyl Ether (EGDE): Model: Denacol EX-810 Manufacturer: Nagase ChemteX Corporation Water (H2O) Model: Milli-Q® Water Manufacturer: MilliporeSigma (Merck) Ethanol (C2H5OH): Model: Absolute Ethanol, 200 Proof Manufacturer: Decon Laboratories, Inc. Methanol (CH3OH): Model: Methanol, HPLC Grade Manufacturer: Fisher Chemical (Thermo Fisher Scientific) Ultrasonic disperser: Model: UP200St Manufacturer: Hielscher Ultrasonics Stirrer: Model: IKA RW 20 digital Manufacturer: IKA Works, Inc. Heating stirrer: Model: Heidolph Hei-Standard Manufacturer: Heidolph Instruments GmbH&Co. KG Cooling equipment: Model: Thermo Scientific™ Arctic A10 Refrigerated Circulator Manufacturer: Thermo Fisher Scientific Mold: Model: Customized according to specific experimental requirements Manufacturer: Sigma-Aldrich or Fisher Scientific Freezing equipment (freezer or refrigerated cabinet): Model: Thermo Scientific™ Forma™ -20°C Manual Defrost Freezer Manufacturer: Thermo Fisher Scientific Freeze dryer: Model: Labconco FreeZone 2.5 Liter Benchtop Freeze Dry System Manufacturer: Labconco Corporation Example 1: In this example, the preparation method of the natural polysaccharide aerogel for cigarettes includes the following steps: S1. Disperse 100 parts of polysaccharide, 1 part of filler, and 1 part of crosslinking agent by weight in 50 parts of solvent, and stir with a stirrer until completely dissolved to form a uniform polysaccharide solution; S2. Add 5 parts of hydrophobic modifier, 5 parts of ion exchange modifier, 5 parts of surfactant, and 3 parts of functional polymer by weight to the polysaccharide solution, and continuously stir and react at 60 °C for 2 h using a heating stirrer to obtain a modified solution; S3. Cool the modified solution to room temperature using a cooling device, then pour it into a mold for gelation, and then place it in a freezing device, cool it to -20 °C, and keep it for 1 h until completely frozen to obtain a frozen gel; S4. Transfer the frozen gel to a freeze dryer and perform sublimation drying under vacuum conditions to obtain a natural polysaccharide aerogel.

[0025] Among them: The hydrophobic modifier is methyltriethoxysilane; The ion exchange modifier is 3-(triethoxysilyl)propanesulfonic acid; The surfactant is octyltriethoxysilane; The functional polymer is polyethyleneimine; The filler is calcium carbonate; The crosslinking agent is glutaraldehyde; The solvent is water; The polysaccharide is cellulose; The power of the ultrasonic disperser is 150 W.

[0026] Example 2: In this example, a method for preparing a natural polysaccharide aerogel for cigarettes includes the following steps: S1. Disperse 200 parts of polysaccharide, 5 parts of filler, and 5 parts of crosslinking agent by weight in 100 parts of solvent, and stir with a stirrer until completely dissolved to form a uniform polysaccharide solution; S2. Add 10 parts of hydrophobic modifier, 10 parts of ion exchange modifier, 10 parts of surfactant, and 5 parts of functional polymer by weight to the polysaccharide solution, and continuously stir and react at 80 °C for 4 h using a heating stirrer to obtain a modified solution; S3. Cool the modified solution to room temperature using a cooling device, then pour it into a mold for gelation, and then place it in a freezing device, cool it to -40 °C, and keep it for 2 hours until completely frozen to obtain a frozen gel; S4. Transfer the frozen gel to a freeze dryer and perform sublimation drying under vacuum conditions to obtain a natural polysaccharide aerogel.

[0027] Among them: The hydrophobic modifier is ethyltriethoxysilane; The ion exchange modifier is 3-(trimethoxysilyl)propanesulfonic acid; The surfactant is trifluoropropyltriethoxysilane; The functional polymer is polyacrylic acid; The filler is barium carbonate; The crosslinking agent is ethylene glycol diglycidyl ether; The solvent is ethanol; The polysaccharide is chitosan; The power of the ultrasonic disperser is 200 W.

[0028] Example 3: In this example, the preparation method of the natural polysaccharide aerogel for cigarettes includes the following steps: S1. Disperse 150 parts of polysaccharide, 3 parts of filler, and 3 parts of crosslinking agent by weight in 75 parts of solvent, and stir with a stirrer until completely dissolved to form a uniform polysaccharide solution; S2. Add 7 parts of hydrophobic modifier, 7 parts of ion exchange modifier, 7 parts of surfactant, and 4 parts of functional polymer by weight to the polysaccharide solution, and continuously stir and react at 70 °C for 3 h with a heating stirrer to obtain a modified solution; S3. Cool the modified solution to room temperature using a cooling device, then pour it into a mold for gelation, and then place it in a freezing device, cool it to -30 °C, and keep it for 1.5 hours until completely frozen to obtain a frozen gel; S4. Transfer the frozen gel to a freeze dryer and perform sublimation drying under vacuum conditions to obtain a natural polysaccharide aerogel.

[0029] Among them: The hydrophobic modifier is methyltrimethoxysilane; The ion exchange modifier is 3-(triethoxysilyl)propanesulfonic acid; The surfactant is sodium dodecyl sulfate; The functional polymer is polyethyleneimine; The filler is barium sulfate; The crosslinking agent is glutaraldehyde; The solvent is methanol; The polysaccharide is sodium alginate; The power of the ultrasonic disperser is 250 W.

[0030] Example 4: In this example, the preparation method of the natural polysaccharide aerogel for cigarettes includes the following steps: S1. Disperse 180 parts of polysaccharide, 4 parts of filler, and 4 parts of crosslinking agent by weight in 80 parts of solvent, and stir with a stirrer until completely dissolved to form a uniform polysaccharide solution; S2. Add 8 parts of hydrophobic modifier, 8 parts of ion exchange modifier, 8 parts of surfactant, and 4.5 parts of functional polymer by weight to the polysaccharide solution, and continuously stir and react at 75 °C for 3.5 h using a heating stirrer to obtain a modified solution; S3. Cool the modified solution to room temperature using a cooling device, then pour it into a mold for gelation, and then place it in a freezing device, cool it to -35 °C, and maintain for 1.8 hours until completely frozen to obtain a frozen gel; S4. Transfer the frozen gel to a freeze dryer and perform sublimation drying under vacuum conditions to obtain a natural polysaccharide aerogel.

[0031] Wherein: The hydrophobic modifier is methyltriethoxysilane; The ion exchange modifier is 3-(triethoxysilyl)propanesulfonic acid; The surfactant is octyltriethoxysilane; The functional polymer is polyethyleneimine; The filler is calcium carbonate; The crosslinking agent is glutaraldehyde; The solvent is a mixture of water and ethanol with a mass ratio of 50% each; The polysaccharide is agar; The power of the ultrasonic disperser is 300 W.

[0032] Example 5: In this example, a method for preparing a natural polysaccharide aerogel for cigarettes includes the following steps: S1. Disperse 200 parts of polysaccharide, 5 parts of filler, and 5 parts of crosslinking agent by weight in 100 parts of solvent, and stir with a stirrer until completely dissolved to form a uniform polysaccharide solution; S2. Add 10 parts of hydrophobic modifier, 10 parts of ion exchange modifier, 10 parts of surfactant, and 5 parts of functional polymer by weight to the polysaccharide solution, and continuously stir and react at 80 °C for 4 h using a heating stirrer to obtain a modified solution; S3. Cool the modified solution to room temperature using a cooling device, then pour it into a mold for gelation, and then place it in a freezing device, cool it to -40 °C, and maintain for 2 hours until completely frozen to obtain a frozen gel; S4. Transfer the frozen gel to a freeze dryer and perform sublimation drying under vacuum conditions to obtain a natural polysaccharide aerogel.

[0033] Wherein: The hydrophobic modifier is methyltriethoxysilane; The ion exchange modifier is 3-(triethoxysilyl)propanesulfonic acid; The surfactant is octyltriethoxysilane; The functional polymer is polyethyleneimine; The filler is calcium carbonate; The crosslinking agent is glutaraldehyde; The solvent is a mixture of water and methanol with each accounting for 50% by mass; The polysaccharide is starch; The power of the ultrasonic disperser is 350 W.

[0034] Example 6: In this example, the preparation method of the natural polysaccharide aerogel for cigarettes includes the following steps: S1. Disperse 200 parts of polysaccharide, 5 parts of filler, and 5 parts of crosslinking agent by weight in 100 parts of solvent, and stir with a stirrer until completely dissolved to form a uniform polysaccharide solution; S2. Add 10 parts of hydrophobic modifier, 10 parts of ion exchange modifier, 10 parts of surfactant, and 5 parts of functional polymer by weight to the polysaccharide solution, and continuously stir and react at 80 °C for 4 h with a heating stirrer to obtain a modified solution; S3. Cool the modified solution to room temperature using a cooling device, then pour it into a mold for gelation, and then place it in a freezing device, cool down to -40 °C, and keep it for 2 hours until completely frozen to obtain a frozen gel; S4. Transfer the frozen gel to a freeze dryer and perform sublimation drying under vacuum conditions to obtain the natural polysaccharide aerogel.

[0035] Wherein: The hydrophobic modifier is methyltriethoxysilane; The ion exchange modifier is 3-(triethoxysilyl)propanesulfonic acid; The surfactant is octyltriethoxysilane; The functional polymer is polyethyleneimine; The filler is calcium carbonate; The crosslinking agent is glutaraldehyde; The solvent is a mixture of ethanol and methanol with each accounting for 50% by mass; The polysaccharide is pectin; The power of the ultrasonic disperser is 200 W.

[0036] Comparative Example 1: In this comparative example, the preparation method of the natural polysaccharide aerogel for cigarettes includes the following steps: S1. Disperse 100 parts of polysaccharide, 1 part of filler, and 1 part of crosslinking agent by weight in 50 parts of solvent, and stir with a stirrer until completely dissolved to form a uniform polysaccharide solution; S2. Add 5 parts of surfactant and 3 parts of functional polymer by weight to the polysaccharide solution, and continuously stir and react at 60 °C for 2 h using a heating stirrer to obtain a modified solution; S3. Cool the modified solution to room temperature using a cooling device, then pour it into a mold for gelation, and then place it in a freezing device, cool it to -20 °C, and keep it for 1 h until completely frozen to obtain a frozen gel; S4. Transfer the frozen gel to a freeze dryer and perform sublimation drying under vacuum conditions to obtain the natural polysaccharide aerogel.

[0037] Wherein: The surfactant is octyltriethoxysilane; The functional polymer is polyethyleneimine; The filler is calcium carbonate; The crosslinking agent is glutaraldehyde; The solvent is water; The polysaccharide is cellulose; The power of the ultrasonic disperser is 150 W.

[0038] Comparative Example 2: In this comparative example, the preparation method of the natural polysaccharide aerogel for cigarettes includes the following steps: S1. Disperse 100 parts of polysaccharide, 1 part of filler, and 1 part of crosslinking agent by weight in 50 parts of solvent, and stir with a stirrer until completely dissolved to form a uniform polysaccharide solution; S2. Add 5 parts of hydrophobic modifier, 5 parts of surfactant, and 3 parts of functional polymer by weight to the polysaccharide solution, and continuously stir and react at 60 °C for 2 h using a heating stirrer to obtain a modified solution; S3. Cool the modified solution to room temperature using a cooling device, then pour it into a mold for gelation, and then place it in a freezing device, cool it to -20 °C, and keep it for 1 h until completely frozen to obtain a frozen gel; S4. Transfer the frozen gel to a freeze dryer and perform sublimation drying under vacuum conditions to obtain the natural polysaccharide aerogel.

[0039] Wherein: The hydrophobic modifier is methyltriethoxysilane; The surfactant is octyltriethoxysilane; The functional polymer is polyethyleneimine; The filler is calcium carbonate; The crosslinking agent is glutaraldehyde; The solvent is water; The polysaccharide is cellulose; The power of the ultrasonic disperser is 150 W.

[0040] Comparative Example 3: In this comparative example, the preparation method of the natural polysaccharide aerogel for cigarettes includes the following steps: S1. Disperse 100 parts of polysaccharide, 1 part of filler, and 1 part of crosslinking agent by weight in 50 parts of solvent, and stir with a stirrer until completely dissolved to form a uniform polysaccharide solution; S2. Add 5 parts of ion exchange modifier, 5 parts of surfactant, and 3 parts of functional polymer by weight to the polysaccharide solution, and continuously stir and react at 60 °C for 2 h with a heating stirrer to obtain a modified solution; S3. Cool the modified solution to room temperature with a cooling device, then pour it into a mold for gelation, and then place it in a freezing device, cool down to -20 °C, and keep it for 1 h until completely frozen to obtain a frozen gel; S4. Transfer the frozen gel to a freeze dryer and perform sublimation drying under vacuum conditions to obtain the natural polysaccharide aerogel.

[0041] Among them: The ion exchange modifier is 3-(triethoxysilyl)propane sulfonic acid; The surfactant is octyltriethoxysilane; The functional polymer is polyethyleneimine; The filler is calcium carbonate; The crosslinking agent is glutaraldehyde; The solvent is water; The polysaccharide is cellulose; The power of the ultrasonic disperser is 150 W.

[0042] Test Example - Tar Reduction Test of Natural Polysaccharide Aerogel for Cigarettes First, apply the natural polysaccharide aerogel to the cigarette filter tip, and the steps are as follows: S01. Prepare the natural polysaccharide aerogel according to the steps of the above-mentioned example or comparative example; S02. Use a ball mill to crush the prepared natural polysaccharide aerogel into fine particles; S03. Select cellulose acetate as the main component of the filter material, and then use a mixing device to uniformly disperse the crushed aerogel particles in the fibrous material to ensure uniform distribution of the aerogel particles; S04. Use a filter forming device to process the fibrous material mixed with aerogel particles into the shape of a filter, and finally assemble the prepared aerogel filter into the filter part of the cigarette, and use standard cigarette manufacturing equipment to assemble the cigarette.

[0043] Then, conduct a tar content test on the prepared cigarettes. The required equipment is as follows: Automatic smoking machine: Simulate the smoking process.

[0044] Glass fiber filter sheet: Used to trap tar in the flue gas.

[0045] Weighing equipment: High-precision analytical balance.

[0046] Solvent: Such as isopropyl alcohol, used to clean the equipment and extract tar.

[0047] Drying equipment: Such as an oven, used to dry the filter sheet.

[0048] The steps are as follows: S11. Ensure that the automatic smoking machine and the analytical balance are in an accurate state, then take an appropriate amount of cigarettes to be tested and install a new glass fiber filter sheet at the appropriate position of the smoking machine; S12. Set the suction volume, frequency, and time of the smoking machine according to the standard method (such as ISO or FTC standard), start the smoking machine, let it simulate the smoking process, and pass the flue gas through the filter sheet; S13. After completing the smoking simulation, carefully remove the filter sheet, weigh the weight change of the filter sheet using a high-precision balance to determine the mass of the tar, and calculate the tar content generated in each cigarette through the weight difference before and after weighing; S14. Repeat steps S11 - S13 to obtain 5 numerical values, and take the average value as the final result.

[0049] Conduct tar content tests on ordinary cigarettes and cigarettes with natural polysaccharide aerogels prepared by the preparation methods of Examples 1 - 6 and Comparative Examples 1 - 3 included in the filter. The results are shown in Table 1 Sample Tar content / mg Example 1 1.4 Example 2 1.2 Example 3 1.3 Example 4 1.4 Example 5 1.1 Example 6 1.6 Comparative Example 1 6.1 Comparative Example 2 4.2 Comparative Example 3 4.5 Ordinary cigarette 8.9 Table 1. Tar content test results of ordinary cigarettes and cigarettes with natural polysaccharide aerogels prepared by the preparation methods of Examples 1 - 6 and Comparative Examples 1 - 3 included in the filter Among them, the examples and comparative examples under "Samples" in Table 1 indicate cigarettes with filters made of natural polysaccharide aerogels prepared by using the preparation methods including these examples or comparative examples; "ordinary cigarettes" refer to cigarettes with the same other components as those in the above examples and comparative examples except for natural polysaccharide aerogels.

[0050] Analysis of the data in Table 1 shows that: 1. Comparing the data of Examples 1-6 and Comparative Examples 1-3, it can be seen that both the ion exchange modifier and the hydrophobic modifier added to the natural polysaccharide aerogel play a role in reducing tar.

[0051] 2. Comparing the data of Comparative Example 1 and Comparative Example 2, it can be seen that the ion exchange modifier added to the natural polysaccharide aerogel can effectively play a role in reducing tar.

[0052] 3. Comparing the data of Comparative Example 1 and Comparative Example 3, it can be seen that the hydrophobic modifier added to the natural polysaccharide aerogel can effectively play a role in reducing tar.

[0053] 4. Comparing the data of Examples 1-6 and Comparative Examples 2-3, it can be seen that when the ion exchange modifier and the hydrophobic modifier added to the natural polysaccharide aerogel are used together, the effect of reducing tar can be further improved.

[0054] In addition, the above specific examples are only explanations of the present invention, and they are not limitations of the present invention. Those skilled in the art can make modifications without creative contributions to these examples according to needs after reading this specification, but as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

Claims

1. A method for preparing natural polysaccharide aerogel for cigarettes, characterized in that: The steps include: S1. Dispersing 100-200 parts by weight of polysaccharide, 1-5 parts of filler, and 1-5 parts of cross-linking agent in 50-100 parts of solvent, stirring with a stirrer until completely dissolved to form a uniform polysaccharide solution; S2. Add 5-10 parts by weight of a hydrophobic modifier, 5-10 parts by weight of an ion exchange modifier, 5-10 parts by weight of a surfactant, and 3-5 parts by weight of a functional polymer to the polysaccharide solution, and stir the mixture at 60-80° C. for 2-4 hours to obtain a modified solution; S3. Cooling the modified solution to room temperature using a cooling device, then pouring it into a mold for gelation, and then placing it in a freezing device, cooling it to -20°C or below and -40°C or above, and keeping it for 1-2 hours until it is completely frozen to obtain a frozen gel; S4. The frozen gel is transferred to a freeze dryer and subjected to sublimation drying under vacuum conditions to obtain a natural polysaccharide aerogel.

2. The method for preparing the natural polysaccharide aerogel for cigarettes according to claim 1, characterized in that: The hydrophobic modifier includes one of methyltriethoxysilane, ethyltriethoxysilane, methyltrimethoxysilane and phenyltriethoxysilane.

3. The method for preparing the natural polysaccharide aerogel for cigarettes according to claim 1, characterized in that: The ion exchange modifier includes one of 3-(triethoxysilyl)propane sulfonic acid and 3-(trimethoxysilyl)propane sulfonic acid.

4. The method for preparing the natural polysaccharide aerogel for cigarettes according to claim 1, characterized in that: The surfactant includes one of octyl triethoxy silane, trifluoropropyl triethoxy silane, sodium dodecyl sulfate and sodium lauryl polyether sulfate.

5. The method for preparing the natural polysaccharide aerogel for cigarettes according to claim 1, characterized in that: The functional polymer includes one of polyethyleneimine and polyacrylic acid.

6. The method for preparing the natural polysaccharide aerogel for cigarettes according to claim 1, characterized in that: The filler includes one of calcium carbonate, barium carbonate and barium sulfate.

7. The method for preparing the natural polysaccharide aerogel for cigarettes according to claim 1, characterized in that: The cross-linking agent includes one of glutaraldehyde and ethylene glycol diglycidyl ether.

8. The method for preparing the natural polysaccharide aerogel for cigarettes according to claim 1, characterized in that: The solvent includes one of water, ethanol and methanol or a mixture of more than one of them.

9. The method for preparing the natural polysaccharide aerogel for cigarettes according to claim 1, characterized in that: The dispersion method is to use an ultrasonic disperser for ultrasonic dispersion with a power of 150-350W.

10. The method for preparing the natural polysaccharide aerogel for cigarettes according to claim 1, characterized in that: The polysaccharide comprises one of cellulose, chitosan, sodium alginate, agar, starch and pectin.