An adsorbing material for preparing a cigarette filter rod, a method for preparing the same, and a cigarette filter rod

Abstract

This invention belongs to the field of adsorption materials technology. It provides an adsorption material for preparing cigarette filter rods, its preparation method, and a solid cigarette filter rod. The adsorption material comprises the following components in parts by weight: 30-50 parts of polylactic acid-glycolic acid copolymer, 15-30 parts of modified starch, 10-25 parts of maltodextrin-modified vermiculite powder, and 5-12 parts of a wetting and dispersing agent. The modified starch is a mixture of maltodextrin and hydroxypropyl starch. The wetting and dispersing agent contains nonionic fluorocarbon segments. The adsorption material of this invention, used in cigarette filter rods, can solve the problem of current cigarette filter rod materials being difficult to biodegrade and easily causing environmental pollution, while also improving the filtration effect on harmful substances such as tar and carbon monoxide, thus facilitating its application.

Description

Technical Field

[0001] This invention belongs to the field of adsorption material technology, and particularly relates to an adsorption material that can be used to prepare cigarette filter rods, its preparation method, and a solid cigarette filter rod. Background Technology

[0002] Although cellulose acetate has some biodegradability, its filtering effect on harmful substances such as tar and carbon monoxide is limited and ineffective. Furthermore, it has strong moisture barrier and adsorption properties, resulting in a dry feeling when inhaled and poor smoking quality. In addition, the main raw material required for the production of cellulose acetate is a limited supply of natural specialty wood pulp. As the market demand for cellulose acetate increases, a shortage of specialty wood pulp is inevitable, thereby increasing production costs for cigarette manufacturers.

[0003] Therefore, there is an urgent need to develop adsorbent materials that are highly biodegradable and have outstanding adsorption effects on harmful substances such as tar and carbon monoxide, in order to reduce dependence on cellulose acetate and provide new ideas for the development of cigarette filter rod materials. Summary of the Invention

[0004] In view of this, the present invention provides an adsorbent material that can be used to prepare cigarette filter rods, a method for preparing the same, and a solid cigarette filter rod. The adsorbent material provided by the present invention has good biodegradability and, when used in cigarette filter rods, has a good adsorption and filtration effect on harmful substances such as tar and carbon monoxide, without affecting the smoking taste, and is easy to apply.

[0005] This invention provides an adsorbent material that can be used to prepare cigarette filter rods, comprising the following components in parts by weight:

[0006] 30-50 parts of polylactic acid-glycolic acid copolymer, 15-30 parts of modified starch, 10-25 parts of maltodextrin-modified vermiculite powder, and 5-12 parts of wetting and dispersing agent.

[0007] The modified starch is a mixture of maltodextrin and hydroxypropyl starch; the wetting and dispersing agent contains nonionic fluorocarbon segments.

[0008] Preferably, in the polylactic acid-glycolic acid copolymer, the molar ratio of lactic acid repeating units to glycolic acid repeating units is 75-90:25-10.

[0009] Preferably, the maltodextrin-modified vermiculite powder is prepared from maltodextrin, a silane coupling agent, and acid-pretreated vermiculite powder.

[0010] Preferably, the wetting and dispersing agent is a mixture of nonionic fluorocarbon activator, polyvinyl alcohol and polysorbate in a mass ratio of 0.01-0.05:1:2-5.

[0011] This invention provides a method for preparing the adsorbent material as described above, comprising the following steps:

[0012] S1. Mix polylactic acid-glycolic acid copolymer and modified starch in parts by weight to obtain a first premix; mix maltodextrin-modified vermiculite powder and wetting and dispersing agent in parts by weight to obtain a second premix;

[0013] S2. The first premix and the second premix are melt-blended, extruded, and granulated to obtain the adsorbent material that can be used to prepare cigarette filter rods.

[0014] Preferably, the maltodextrin-modified vermiculite powder is obtained according to the following steps:

[0015] Vermiculite powder was mixed with a sulfuric acid solution with a pH of 3-5 and then ultrasonically treated. After filtration, washing, drying, and calcination, acid-pretreated vermiculite powder was obtained.

[0016] Maltodextrin, silane coupling agent, glycerol and water are mixed, and acid-pretreated vermiculite powder is added. The mixture is refluxed at 60-100°C for 1-3 hours, and then filtered, washed and dried to obtain maltodextrin-modified vermiculite powder.

[0017] Preferably, the melt blending process has four stages, wherein the temperature of the first stage is 90-115℃, the temperature of the second stage is 120-160℃, the temperature of the third stage is 175-195℃, and the temperature of the fourth stage is 198-210℃.

[0018] Preferably, the granulation process further includes passing the material through a 60-mesh sieve and drying it to obtain the solid particles of the adsorbent material.

[0019] The water content of the solid particles of the adsorbent material is ≤0.2wt%.

[0020] This invention provides a cigarette filter rod, which is made by mixing the adsorbent material and binder described above and then molding it.

[0021] Preferably, the adsorbent material is a solid particle, and the mass ratio of the adsorbent to the binder is 1.5-3:1;

[0022] The temperature of the heating section in the molding process is preferably controlled at 120-136℃.

[0023] Compared with existing technologies, the adsorbent material for cigarette filters provided by this invention, by weight, is prepared from raw materials comprising the following components: 30-50 parts of polylactic acid-glycolic acid copolymer, 15-30 parts of modified starch, 10-25 parts of maltodextrin-modified vermiculite powder, and 5-12 parts of wetting and dispersing agent. The modified starch is a mixture of maltodextrin and hydroxypropyl starch; the wetting and dispersing agent contains nonionic fluorocarbon segments. The adsorbent material of this invention, using a composite of polylactic acid-glycolic acid copolymer and modified starch as a base material, achieves good biodegradability. The polylactic acid-glycolic acid copolymer itself has good plasticity, while the modified starch has good adsorption properties. The combination of the two is beneficial for obtaining a base material with good plasticity and stability as well as excellent adsorption properties. To further improve the adsorption characteristics of the substrate, this invention introduces an appropriate amount of maltodextrin-modified vermiculite powder into the substrate, further enhancing its adsorption performance. Since maltodextrin itself is a type of modified starch, it has good compatibility with the modified starch in the substrate. In this case, the modified starch in the substrate can act as an intermediate carrier. The wetting and dispersing agent of this invention may contain a nonionic fluorocarbon activator, which not only helps improve the uniformity of dispersion of maltodextrin-modified vermiculite powder in the substrate, but also helps improve the thermal stability of the polylactic acid-glycolic acid copolymer in the substrate during thermoplastic molding, inhibiting significant thermal degradation and residual odor. Therefore, the adsorption material described in this invention, when used in cigarette filter rods, can solve the problem of current cigarette filter rod materials being difficult to biodegrade and easily causing environmental pollution, while also improving the filtration effect on harmful substances such as tar and carbon monoxide.

[0024] Furthermore, in this embodiment of the invention, a mixture of nonionic fluorocarbon activator, polyvinyl alcohol and polysorbate is preferably used as a wetting and dispersing agent. It can work synergistically with the modified starch in the substrate to improve the dispersion uniformity of maltodextrin modified vermiculite powder in the substrate, and better improve the compatibility between maltodextrin modified vermiculite powder and the substrate. This helps to avoid the phenomenon of vermiculite powder precipitating from the substrate during plastic molding. Detailed Implementation

[0025] The technical solutions in the embodiments of this application are described clearly and completely below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0026] This invention provides an adsorbent material that can be used to prepare cigarette filter rods, comprising the following components in parts by weight:

[0027] 30-50 parts of polylactic acid-glycolic acid copolymer, 15-30 parts of modified starch, 10-25 parts of maltodextrin-modified vermiculite powder, and 5-12 parts of wetting and dispersing agent.

[0028] The modified starch is a mixture of maltodextrin and hydroxypropyl starch; the wetting and dispersing agent contains nonionic fluorocarbon segments.

[0029] The adsorption material provided by this invention has good biodegradability. When used in cigarette filter rods, it has a good adsorption and filtration effect on harmful substances such as tar and carbon monoxide, without affecting the smoking taste.

[0030] The adsorbent material formulation of this invention comprises: 30-50 parts by weight of polylactic acid-glycolic acid copolymer and 15-30 parts by weight of modified starch. Polylactic acid-glycolic acid copolymer (PLGA) can be prepared by ring-opening polymerization, typically by dehydrating and cyclizing glycolic acid and lactic acid separately to synthesize glycolide (GA) and lactide (LA) monomers, followed by ring-opening polymerization. Due to the presence of structural units such as glycolic acid, polylactic acid-glycolic acid copolymer itself possesses excellent biodegradability; moreover, its toughness, strength, and molding stability are relatively good.

[0031] In embodiments of the present invention, the molar ratio of lactic acid repeating units to glycolic acid repeating units in the polylactic acid-glycolic acid copolymer is 75-90:25-10, preferably 75:25 or 85:15; the molecular weight of the polylactic acid-glycolic acid copolymer can be 45,000 to 80,000, and more preferably 50,000 to 70,000, and commercially available products can be used.

[0032] The modified starch of this invention is prepared by mixing maltodextrin and hydroxypropyl starch, preferably in a mass ratio of 1:1-2. The microstructure of starch is a natural starch macromolecule with a cyclic structure composed of glucose units. Hydroxypropylation of starch is a form of starch etherification; hydroxypropylated starch can reduce starch degradation and alter its gelatinization temperature, viscosity, and other properties. Maltodextrin is a biomodified starch obtained through enzymatic treatment, also known as water-soluble dextrin or enzymatic dextrin. The modified starch of this invention is a starch derivative obtained through a composite modification method, which can be achieved by directly mixing maltodextrin and hydroxypropyl starch in a mass ratio of 1:1-2.

[0033] If only modified starch is used, the molding stability of the adsorption substrate is not good enough. The present invention combines the polylactic acid-glycolic acid copolymer and modified starch, which is beneficial to obtain a substrate with good plastic molding stability and excellent adsorption properties, without significantly increasing the cost.

[0034] To ensure good strength and molding stability, and to further improve adsorption characteristics, the adsorption material of this invention comprises 10-25 parts by mass of maltodextrin-modified vermiculite powder. In a preferred embodiment of this invention, the maltodextrin-modified vermiculite powder is prepared from maltodextrin, a silane coupling agent, and acid-pretreated vermiculite powder. The mass ratio of the maltodextrin, silane coupling agent, and acid-pretreated vermiculite powder can be 25-40:2-6:100. Preferably, the silane coupling agent is a mixture of γ-glycidoxypropyltrimethoxysilane and γ-aminopropyltriethoxysilane at a molar ratio of 1:1. The maltodextrin is a modified starch product with a hydrolysis DE value below 20%.

[0035] In some embodiments of this invention, silane coupling agents can be used to bond silane groups to the surface of vermiculite powder. The organic functional groups (e.g., amino, epoxy groups) in the silane coupling agent can react with the active functional groups (e.g., hydroxyl groups) in maltodextrin, resulting in a stable bond between maltodextrin and vermiculite powder. This not only expands the specific surface area of ​​the vermiculite powder pores, further enhancing its adsorption performance, but also, since maltodextrin itself is a type of modified starch, it has good compatibility with the modified starch in the substrate, which is beneficial for molding performance. However, using excessive amounts of modified vermiculite increases costs and may also degrade product performance to some extent.

[0036] In embodiments of the present invention, the maltodextrin-modified vermiculite powder is preferably obtained according to the following steps:

[0037] Vermiculite powder was mixed with a sulfuric acid solution with a pH of 3-5 and then ultrasonically treated. After filtration, washing, drying, and calcination, acid-pretreated vermiculite powder was obtained.

[0038] Maltodextrin, silane coupling agent, glycerol and water are mixed, and acid-pretreated vermiculite powder is added. The mixture is refluxed at 60-100°C for 1-3 hours, and then filtered, washed and dried to obtain maltodextrin-modified vermiculite powder.

[0039] Specifically, the maltodextrin-modified vermiculite powder is prepared by the following method:

[0040] ① Add the ground vermiculite powder to a sulfuric acid solution with a pH of 3-5 to prepare a slurry with a concentration of 10-20%. Sonicate the slurry at 65-80℃ for 0.5-2 hours, then cool it to room temperature. After filtration and washing until neutral, dry and calcine to obtain pretreated vermiculite powder.

[0041] ② At room temperature, add maltodextrin, silane coupling agent and glycerol to water and stir to mix evenly. Then heat to 60-70°C and slowly add the pretreated vermiculite powder while stirring. After the pretreated vermiculite powder has been added, continue to heat to 85-100°C and reflux for 1-3 hours. Then cool to room temperature, filter, wash and dry to obtain maltodextrin modified vermiculite powder.

[0042] In the above preparation process, in step ①, the vermiculite powder after grinding is 90% powder that passes through a 400-mesh sieve; the frequency of the ultrasonic treatment can be 25-40KHz; the preferred calcination conditions are: calcination at 320-460℃ for 1.5-2.5h.

[0043] In the above preparation process, in step ②, the mass ratio of maltodextrin, silane coupling agent, glycerol, water and pretreated vermiculite powder is 25-40: 2-6: 0.5-1.2: 400-500: 100.

[0044] The adsorbent material formulation of this invention contains 5-12 parts by weight of a wetting and dispersing agent, which contains nonionic fluorocarbon segments, thus improving material performance and processing. Preferably, the wetting and dispersing agent comprises a nonionic fluorocarbon activator, polyvinyl alcohol, and polysorbate, further prepared by mixing the nonionic fluorocarbon activator, polyvinyl alcohol, and polysorbate in a mass ratio of 0.01-0.05:1:2-5 to achieve better results.

[0045] The wetting and dispersing agent of this invention preferably contains a nonionic fluorocarbon surfactant, which not only improves the dispersion uniformity of maltodextrin-modified vermiculite powder in the substrate, but also improves the thermal stability of the polylactic acid-glycolic acid copolymer in the substrate during thermoplastic molding, ensuring good product performance and odor. Fluorocarbon surfactants are surfactants formed by replacing hydrogen atoms in the hydrophobic groups of hydrocarbon surfactants with fluorine atoms. Nonionic fluorocarbon surfactants can be classified according to their molecular structure into polyether type, polyethylene glycol type, polyol type, etc., among which the hydrophilic chain is mostly polyoxyethylene. This invention can use most commercially available nonionic fluorocarbon surfactants, preferably the commercially available Capstone FS-3100 (Chemours), which is based on a six-carbon fluorine chain and requires only a low dosage. Furthermore, polyvinyl alcohol (PVA) is generally soluble in water, and polysorbate, also known as polyoxyethylene dehydrated sorbitan monooleate, can be used with commonly used wetting and dispersing types.

[0046] In this embodiment of the invention, a mixture of nonionic fluorocarbon activator, polyvinyl alcohol and polysorbate is preferably used as a wetting and dispersing agent. It can work synergistically with the modified starch in the substrate to improve the dispersion uniformity of maltodextrin modified vermiculite powder and make the components more compatible.

[0047] The adsorbent material provided in this embodiment of the invention, which can be used to prepare cigarette filter rods, is a solid adsorbent particle that can pass through a 60-mesh sieve; its water content does not exceed 0.2 wt%.

[0048] This invention provides a method for preparing the adsorbent material as described above, comprising the following steps:

[0049] S1. Mix polylactic acid-glycolic acid copolymer and modified starch in parts by weight to obtain a first premix; mix maltodextrin-modified vermiculite powder and wetting and dispersing agent in parts by weight to obtain a second premix;

[0050] S2. The first premix and the second premix are melt-blended, extruded, and granulated to obtain the adsorbent material that can be used to prepare cigarette filter rods.

[0051] In a specific embodiment of the present invention, the above-mentioned adsorbent material can be prepared by the following steps:

[0052] Step 1): Mix polylactic acid-glycolic acid copolymer and modified starch evenly according to parts by weight to obtain premix A; and mix maltodextrin modified vermiculite powder and wetting and dispersing agent evenly according to parts by weight to obtain premix B;

[0053] Step 2): Premix A and premix B are added to the twin-screw extruder through the main feed port and side feed port, respectively. After melt blending, they are extruded, granulated, and then passed through a 60-mesh vibrating screen. The granules are then placed in a dryer to dry, thus obtaining solid particles of the adsorbent material.

[0054] In the above preparation method, the functions and parameters of each raw material are as described above. After preparing and mixing the raw material components separately, this embodiment of the invention uses a conventional twin-screw extruder to prepare adsorbent particles. Specifically, the melt blending conditions include: the twin-screw extruder has four blending sections; the temperature of the first section is 90-115℃, the temperature of the second section is 120-160℃, the temperature of the third section is 175-195℃, and the temperature of the fourth section is 198-210℃; and the rotation speed of the twin-screw extruder can be controlled at 300-500 rpm.

[0055] In the second step of the preparation method of the adsorbent material, the water content of the solid particles obtained after drying is ≤0.2wt%.

[0056] The adsorbent material prepared in this invention is biodegradable and environmentally friendly. Furthermore, it addresses the limitations and poor performance of existing cigarette filter rods in filtering harmful substances such as tar and carbon monoxide. Additionally, existing filter rods filter mainstream smoke with low moisture content, affecting the smoking experience, while this invention provides better filtration of these harmful substances while maintaining a pleasant smoking experience.

[0057] This invention also provides a cigarette filter rod, which is made by mixing the adsorbent material and binder described above and then molding it.

[0058] The preparation process of the aforementioned cigarette solid filter rod may include:

[0059] Using the solid particles obtained above, a solid filter rod for cigarettes is prepared through the following operations: the solid particles are mixed evenly with a binder to obtain a blank. The blank is continuously fed from the inlet end of a cylindrical stainless steel mold with an inner diameter of 7.6 mm through a continuous pneumatic filling device. The blank passes through the heating section and cooling section of the cylindrical stainless steel mold in sequence and is bonded and formed into a solid filter rod. Further, it can be extruded from the outlet end of the cylindrical stainless steel mold and then quantitatively cut according to the length specifications of the product to obtain a solid filter rod for cigarettes with a diameter of 7.6 mm and an adjustable length (its diameter is not limited to this specification).

[0060] Specifically, in the preparation process of the above-mentioned solid filter rod, the mass ratio of the adsorbent material solid particles to the binder is preferably 1.5-3:1; wherein, the binder is preferably a mixture of polycaprolactone, gelatin and carrageenan in a mass ratio of 1:0.5-1:1-2.

[0061] In addition, when the billet passes through the heating section and cooling section of the cylindrical stainless steel mold in sequence, it is preferable to control the temperature of the heating section to 120-136℃ and the temperature of the cooling section to 35-50℃.

[0062] In summary, the adsorbent material provided by this invention for use in cigarette filter rods has good biodegradability, good adsorption and filtration effect on harmful substances such as tar and carbon monoxide, does not affect the smoking taste, and is beneficial for the application of materials such as cigarette filter rods.

[0063] To better understand the technical content of this invention, specific embodiments are provided below to further illustrate the invention. Unless otherwise specified, all figures are parts by weight.

[0064] In the following examples, most of the raw materials used were commercially available products. Specifically, maltodextrin and hydroxypropyl starch were mixed at a mass ratio of 1:1-2 to obtain modified starch. In the wetting and dispersing agents, polyvinyl alcohol (PVA 26-99(L)) was purchased from Anhui Wanwei High-Tech Materials Co., Ltd., and polysorbate (polysorbate-80) was purchased from Jinan Xiangfeng Weiye Chemical Co., Ltd.; the maltodextrin-modified vermiculite powder was prepared in-house.

[0065] Preparation of maltodextrin-modified vermiculite powder I:

[0066] ① After grinding, 90% of the vermiculite powder that has passed through a 400-mesh sieve is added to a sulfuric acid solution with a pH of 3 to prepare a 10wt% slurry. The slurry is then ultrasonically treated at 70℃ with a frequency of 25KHz for 1 hour, then cooled to room temperature, filtered, washed until neutral, dried, and calcined at 380℃ for 2.5 hours to obtain pretreated vermiculite powder.

[0067] ② At room temperature, according to the mass ratio of maltodextrin, silane coupling agent (a mixture of γ-glycidoxypropyltrimethoxysilane and γ-aminopropyltriethoxysilane in a molar ratio of 1:1), glycerol, water, and pretreated vermiculite powder of 30:4:0.8:420:100, first add maltodextrin, silane coupling agent, and glycerol to water and stir to mix evenly. Then heat to 65°C and slowly add pretreated vermiculite powder while stirring. After the pretreated vermiculite powder has been added, continue to heat to 92°C and reflux for 1.5 hours. Then cool to room temperature, and after filtration, washing, and drying, maltodextrin-modified vermiculite powder can be obtained.

[0068] Preparation of maltodextrin-modified vermiculite powder II:

[0069] ① After grinding, 90% of the vermiculite powder that has passed through a 400-mesh sieve is added to a sulfuric acid solution with a pH of 5 to prepare a 16wt% slurry. The slurry is then ultrasonically treated at 80℃ with a frequency of 32KHz for 2 hours, then cooled to room temperature, filtered, washed until neutral, dried, and calcined at 460℃ for 1.5 hours to obtain pretreated vermiculite powder.

[0070] ② At room temperature, according to the mass ratio of maltodextrin, silane coupling agent (a mixture of γ-glycidoxypropyltrimethoxysilane and γ-aminopropyltriethoxysilane in a molar ratio of 1:1), glycerol, water, and pretreated vermiculite powder of 35:2:0.5:460:100, first add maltodextrin, silane coupling agent, and glycerol to water and stir until evenly mixed. Then, heat to 60°C and slowly add pretreated vermiculite powder while stirring. After the pretreated vermiculite powder has been added, continue heating to 86°C and reflux for 3 hours. Then cool to room temperature, and after filtration, washing, and drying, maltodextrin-modified vermiculite powder can be obtained.

[0071] Preparation of maltodextrin-modified vermiculite powder III:

[0072] ① After grinding, 90% of the vermiculite powder that has passed through a 400-mesh sieve is added to a sulfuric acid solution with a pH of 3.5 to prepare a 20wt% slurry. The slurry is then ultrasonically treated at 65℃ with a frequency of 40KHz for 0.5h, cooled to room temperature, filtered, washed until neutral, dried, and calcined at 320℃ for 2h to obtain pretreated vermiculite powder.

[0073] ② At room temperature, according to the mass ratio of maltodextrin, silane coupling agent (a mixture of γ-glycidoxypropyltrimethoxysilane and γ-aminopropyltriethoxysilane in a molar ratio of 1:1), glycerol, water, and pretreated vermiculite powder of 40:6:1.2:500:100, first add maltodextrin, silane coupling agent, and glycerol to water and stir until evenly mixed. Then, heat to 68°C and slowly add pretreated vermiculite powder while stirring. After the pretreated vermiculite powder has been added, continue heating to 100°C and reflux for 2 hours. Then cool to room temperature, and after filtration, washing, and drying, maltodextrin-modified vermiculite powder can be obtained.

[0074] Preparation of maltodextrin-modified vermiculite powder IV:

[0075] ① After grinding, 90% of the vermiculite powder that has passed through a 400-mesh sieve is added to a sulfuric acid solution with a pH of 4.5 to prepare a 12wt% slurry. The slurry is then ultrasonically treated at 75℃ with a frequency of 28KHz for 1 hour, then cooled to room temperature, filtered, washed until neutral, dried, and calcined at 400℃ for 1.5 hours to obtain pretreated vermiculite powder.

[0076] ② At room temperature, according to the mass ratio of maltodextrin, silane coupling agent (a mixture of γ-glycidoxypropyltrimethoxysilane and γ-aminopropyltriethoxysilane in a molar ratio of 1:1), glycerol, water, and pretreated vermiculite powder of 32:5:0.8:480:100, first add maltodextrin, silane coupling agent, and glycerol to water and stir until evenly mixed. Then, heat to 70°C and slowly add pretreated vermiculite powder while stirring. After the pretreated vermiculite powder has been added, continue heating to 95°C and reflux for 1.5 hours. Then cool to room temperature, and after filtration, washing, and drying, maltodextrin-modified vermiculite powder can be obtained.

[0077] Examples 1-4: Preparation of Adsorption Particles

[0078] Prepare the materials according to Tables 1 and 2 below, and then prepare the adsorption particles through the following steps:

[0079] Step 1): Mix polylactic acid-glycolic acid copolymer and modified starch evenly according to the weight parts to obtain premix A; and

[0080] Maltodextrin-modified vermiculite powder and wetting and dispersing agent are mixed evenly according to the weight parts to obtain premix B;

[0081] Step 2): Add premix A and premix B into the twin-screw extruder through the main feed port and side feed port, respectively. After melt blending (see Table 3 for 4-stage temperature process control), extrude and granulate. Then, pass the granules through a 60-mesh vibrating screen and place them in a dryer to dry, controlling the moisture content of the granules to ≤0.2wt%.

[0082] Table 1. Weight parts of each component

[0083]

[0084] Table 2 Detailed information for each component

[0085]

[0086]

[0087] Table 3 Temperature settings in the melt blending section of a twin-screw extruder

[0088] project First segment temperature Second temperature Third temperature segment Fourth temperature Example 1 90℃ 120℃ 175℃ 198℃ Example 2 95℃ 135℃ 180℃ 200℃ Example 3 105℃ 150℃ 186℃ 206℃ Example 4 115℃ 160℃ 195℃ 210℃

[0089] Note: The speed of the twin-screw extruder is controlled at 400 rpm.

[0090] Comparative Example 1:

[0091] This comparative example is basically the same as Example 3 above, except that commercially available vermiculite powder is used directly instead of maltodextrin modified vermiculite powder III.

[0092] Comparative Example 2:

[0093] This comparative example is basically the same as Example 3 above, except that the wetting and dispersing agent used does not contain Capstone FS-3100.

[0094] Comparative Example 3:

[0095] This comparative example is basically the same as Example 3 above, except that commercially available vermiculite powder is used directly instead of maltodextrin modified vermiculite powder III, and the wetting and dispersing agent used does not contain Capstone FS-3100.

[0096] The adsorption particles obtained in Examples 1-4 and Comparative Examples 1-3 above were used to prepare solid filter rods through the following steps:

[0097] After the adsorbent material solid particles are mixed evenly with the binder to obtain a blank, the blank is continuously fed into the inlet end of a cylindrical stainless steel mold with an inner diameter of 7.6 mm through a continuous pneumatic filling device. The blank passes through the heating section and cooling section of the cylindrical stainless steel mold in sequence. The temperature of the heating section is controlled at 125°C and the temperature of the cooling section is controlled at 42°C. The blank is bonded and formed into a solid filter rod and extruded from the outlet end of the cylindrical stainless steel mold. Then, it is quantitatively cut according to the length specifications of the product to obtain a solid filter rod with a diameter of 7.6 mm and an adjustable length for cigarettes.

[0098] Specifically, in the preparation process of the above-mentioned solid filter rod, the mass ratio of solid particles to binder is 2.5:1; wherein the binder is composed of polycaprolactone, gelatin and carrageenan mixed in a mass ratio of 1:0.5:2.

[0099] The appearance quality and odor of the solid filter rods made from the adsorption particles obtained in Examples 1-4 and Comparative Examples 1-3 are shown in Table 4 below.

[0100] Table 4. Apparent quality of the solid filter rods prepared according to the embodiments of the present invention.

[0101]

[0102] Note: The quality of the product is judged by visual inspection and by smell.

[0103] For the solid filter rods made from the adsorbent particles obtained in Examples 1-4 and Comparative Examples 1-3, the fiber bundles in the cigarette filter were manually replaced using Hongwan cigarettes. That is, the fiber bundles were pulled out with tweezers, cut off half, and then a solid filter rod of the same length was cut to replace the cut fiber bundles and stuffed back into the cigarette filter to obtain the sample cigarette to be tested.

[0104] The test results of the mainstream flue gas conventional indicators are shown in Table 5 below.

[0105] Table 5 Test results of sample smoke in the embodiments of the present invention

[0106]

[0107] As shown in Table 5, the solid filter rod made from the adsorption material of the present invention can effectively improve the filtration effect on harmful substances such as tar and carbon monoxide, and has obvious effects in reducing tar and harm. It can also effectively increase the moisture content of mainstream smoke, thereby improving the smoking quality of cigarettes.

[0108] The above description of the embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. An adsorbent material useful in the manufacture of a cigarette filter rod, characterized in that, Components comprising the following weight parts: 30-50 parts of polylactic acid-glycolic acid copolymer, 15-30 parts of modified starch, 10-25 parts of malt dextrin modified vermiculite powder, and 5-12 parts of wet dispersant; The modified starch is mixed from malt dextrin and hydroxypropyl starch; the wet dispersant contains a non-ionic fluorocarbon segment.

2. The adsorbent material of claim 1, wherein, In the polylactic acid-glycolic acid copolymer, the molar ratio of lactic acid repeating units to glycolic acid repeating units is 75-90:25-10.

3. The adsorbent material of claim 1, wherein, The malt dextrin modified vermiculite powder is prepared from malt dextrin, silane coupling agent and acid pretreated vermiculite powder.

4. The adsorbent material of any one of claims 1-3, wherein, The wet dispersant is mixed from non-ionic fluorocarbon active agent, polyvinyl alcohol and polysorbate in a mass ratio of 0.01-0.05:1:2-5.

5. The method of producing an adsorbent material according to any one of claims 1 to 4, wherein The method comprises the following steps: S1, mixing polylactic acid-glycolic acid copolymer and modified starch by weight parts to obtain a first premix; mixing malt dextrin modified vermiculite powder and wet dispersant by weight parts to obtain a second premix; S2, melt blending the first premix and the second premix, extruding and granulating to prepare the adsorbent material that can be used to prepare a cigarette filter rod.

6. The method of claim 5, wherein the adsorbent material is prepared by a process comprising: The malt dextrin modified vermiculite powder is obtained by the following steps: Mixing vermiculite powder with sulfuric acid solution with pH 3-5 and then ultrasonic treatment, filtering and washing, and then drying and calcining to obtain acid pretreated vermiculite powder; Mixing malt dextrin, silane coupling agent, glycerol and water, adding the acid pretreated vermiculite powder, refluxing at 60-100℃ for 1-3h, and then filtering, washing and drying to obtain malt dextrin modified vermiculite powder.

7. The method of claim 5, wherein the adsorbent material is prepared by a process comprising: The melt blending is divided into 4 sections, wherein the first section temperature is 90-115℃, the second section temperature is 120-160℃, the third section temperature is 175-195℃, and the fourth section temperature is 198-210℃.

8. The method of claim 5-7, wherein the adsorbent material is prepared by a process comprising: After granulation, it further comprises passing through a 60 mesh sieve and drying to obtain the adsorbent material solid particles; The water content of the adsorbent material solid particles is ≤0.2wt%.

9. A cigarette solid filter rod, characterized by, Mixing the adsorbent material according to any one of claims 1-4 with a binder and then forming by a forming process.

10. The cigarette solidified filter stick according to claim 9, wherein The adsorbent material is a solid particle, and the mass ratio of the adsorbent material to the binder is 1.5-3:1; The heating section temperature of the forming process is controlled at 120-136℃.

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