CN113322034B

CN113322034B - Hot melt adhesive for filter stick and preparation method and application thereof

Info

Publication number: CN113322034B
Application number: CN202110639089.6A
Authority: CN
Inventors: 耿志忠; 董彦林; 张弘胤; 曹贵昌
Original assignee: Beijing Changrun Chemicals Co ltd
Current assignee: Beijing Changrun Chemicals Co ltd
Priority date: 2021-06-08
Filing date: 2021-06-08
Publication date: 2022-04-26
Anticipated expiration: 2041-06-08
Also published as: CN113322034A

Abstract

The invention provides a hot melt adhesive for filter rods and a preparation method and application thereof, and relates to the technical field of adhesive synthesis, wherein the hot melt adhesive for filter rods is mainly prepared from the following raw materials in percentage by weight: 20-60% of main resin, 5-25% of wax, 5-35% of modifier, 20-60% of tackifying resin and 0.1-3.0% of auxiliary agent; the modifier is alkyl siloxane and/or polyfluoroalkylalkoxysilane. The hot melt adhesive disclosed by the invention has excellent glycerol acetate resistance, is applied to the production of filter sticks in the cigarette industry, and is suitable for popularization and application.

Description

Hot melt adhesive for filter stick and preparation method and application thereof

Technical Field

The invention relates to the technical field of adhesive synthesis, in particular to a hot melt adhesive for filter rods and a preparation method and application thereof.

Background

In the cigarette making process, an adhesive is needed to bond the filter stick, namely the high-transparency wrapping paper is used for wrapping the filter stick material and the adhesive is used for bonding and edge sealing. The cigarette holder filter stick bonding and edge sealing process has two types, one is that the water adhesive and the hot melt adhesive are used simultaneously, and the purpose is to provide initial adhesion by utilizing the fast curing property of the hot melt adhesive and provide final adhesion after moisture in the water adhesive is volatilized and cured in the later period. The other method is to directly use hot melt adhesive for bonding.

The enterprise standard YQ 5-2019 of China tobacco enterprise general company enterprise (hereinafter referred to as the standard) implemented in 2019 for the safety and sanitation of the adhesive for cigarettes provides further requirements for the sanitation of the adhesive for cigarettes. The implementation of the "standard" has little impact on the process where both the water glue and the hot melt glue are used simultaneously, as the water glue still provides the adhesive force. But has a great impact on filter rod products which directly use hot melt glue technology. At present, filter stick products produced by hot melt adhesives synthesized by enterprises under the standard condition are often subjected to the problems of opening (glue opening), cutting, line opening and the like in the storage process, so that the formed filter sticks cannot be used in the product validity period (generally 6 months), and millions of dollars of economic loss are caused.

In view of the above, the present invention is particularly proposed.

Disclosure of Invention

One of the purposes of the invention is to provide a hot melt adhesive for filter sticks, which solves the problem of bonding failure caused by the direct use of a hot melt adhesive process in the production of filter sticks in the existing cigarette industry.

The second purpose of the invention is to provide a preparation method of the hot melt adhesive for the filter stick.

The invention also aims to provide application of the hot melt adhesive for the filter stick in preparation of cigarette filter stick products.

In order to achieve the above purpose of the present invention, the following technical solutions are adopted:

in a first aspect, the invention provides a hot melt adhesive for filter sticks, which is mainly prepared from the following raw materials in percentage by weight: 20-60% of main resin, 5-25% of wax, 5-35% of modifier, 20-60% of tackifying resin and 0.1-3.0% of auxiliary agent;

the modifier is alkyl siloxane and/or polyfluoroalkylalkoxysilane;

the alkyl carbon atom number of the alkyl siloxane is 8-30, the boiling point of the alkyl siloxane is more than 150 ℃, and the surface energy of the alkyl siloxane is less than 30 mN/m;

the polyfluoroalkyl alkoxy silane has the polyfluoroalkyl carbon atom number of 8-30, the alkoxy carbon atom number of 1 or 2, the boiling point of the polyfluoroalkyl alkoxy silane is more than 150 ℃, and the surface energy is less than 30 mN/m.

Further, the alkyl siloxane comprises one or more of dodecyl siloxane and hexadecyl heptasiloxane.

Further, the polyfluoroalkylalkoxysilane comprises one or more of tridecafluorooctyltrimethoxysilane, tridecafluorooctyltriethoxysilane, heptadecafluorodecyltrimethoxysilane or heptadecafluorodecyltriethoxysilane.

Preferably, the polyfluoroalkylalkoxysilane has a polyfluoroalkyl group having 10 to 20 carbon atoms, an alkoxy group having 1 or 2 carbon atoms, a boiling point of more than 150 ℃, and a surface energy of less than 25 mN/m.

Further, the hot melt adhesive for the filter stick is mainly prepared from the following raw materials in percentage by weight: 25-50% of main resin, 8-20% of wax, 8-25% of modifier, 20-50% of tackifying resin and 0.1-1.0% of auxiliary agent.

Further, the main body resin comprises one or more of 1-octene and ethylene copolymer resin, polyvinyl acetate and ethylene copolymer resin, polyethylene resin, polypropylene resin or polyethylene and propylene copolymer resin;

preferably, the melt viscosity of the host resin at 175 ℃ is 2000-100000mPa.s, the melt index at 190 ℃ is 50-1200g/10min, and the surface energy is less than 35 mN/m.

Further preferably, the melt viscosity of the host resin at 175 ℃ is 6000-50000mPa.s and 2.16kg, the melt index at 190 ℃ is 400-1200g/10min, and the surface energy is less than 30 mN/m.

Further, the wax comprises one or more of Fischer-Tropsch wax, microcrystalline wax, polyethylene wax or paraffin wax;

preferably, the ring and ball softening point of the wax is 60-130 ℃, and the surface energy is less than 35 mN/m;

further preferably, the wax has a ring and ball softening point of 70-90 ℃ and a surface energy of less than 30 mN/m.

Further, the tackifying resin comprises one or more of rosin and derivatives thereof, terpene resin and derivatives thereof, petroleum resin and derivatives thereof, polymerized cyclopentadiene and hydrides thereof, styrene polymers, and mixtures of alpha-methyl styrene and vinyl toluene polymers;

preferably, the ring-and-ball softening point of the tackifying resin is 60-130 ℃, and the surface energy is less than 50 mN/m;

further preferably, the tackifying resin has a ring and ball softening point of 70-100 ℃ and a surface energy of less than 45 mN/m.

Further, the auxiliary agent comprises an antioxidant;

preferably, the antioxidant comprises pentaerythritol tetrakis [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ] and/or 2, 6-di-tert-butyl-p-cresol.

In a second aspect, the invention provides a preparation method of the hot melt adhesive for the filter stick, which comprises the following steps:

mixing the main resin, the wax, the modifier, the tackifying resin and the auxiliary agent according to the raw material metering proportion to obtain the hot melt adhesive for the filter rod;

preferably, the method comprises the following steps:

(a) sequentially adding main resin, wax, tackifying resin and auxiliary agent into a container according to the raw material metering ratio, starting heating, starting stirring after the material temperature reaches 120-130 ℃, wherein the stirring speed is 20-50r/min, the vacuum is 1-2.5h, and the vacuum degree is between-0.09 MPa and-0.1 MPa;

(b) stopping stirring, removing vacuum, adding modifier, and stirring at 20-50r/min for 40-100 min; cooling to 100 ℃ and 120 ℃, discharging, granulating by a steel belt, and carrying out vacuum packaging.

In a third aspect, the invention provides an application of the hot melt adhesive for the filter stick in preparation of a cigarette filter stick product.

The hot melt adhesive for the filter stick and the preparation method and application thereof provided by the invention at least have the following beneficial effects:

the hot melt adhesive mainly comprises main resin, wax, a modifier, tackifying resin and an auxiliary agent, wherein the surface energy of a hot melt adhesive film is gradually reduced in the storage process by adopting the specific modifier alkyl siloxane and/or fluoroalkyl alkoxy silane with low surface energy and high boiling point, a protective layer is formed on the surface of the hot melt adhesive, the glyceryl triacetate resistance is realized, and the problems of poor glyceryl triacetate resistance and finally bonding failure caused by overhigh surface energy in the hot melt adhesive technology for producing filter sticks in the existing cigarette industry are solved. The hot melt adhesive has excellent glycerol acetate resistance, is an environment-friendly, low-surface-energy and high-glycerol triacetate-resistant hot melt adhesive, can be used in the field of filter stick bonding in the cigarette industry, and is suitable for popularization and application.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Cellulose diacetate tows are used for producing cigarette holder filter sticks in the cigarette industry in China, and the cigarette holder filter sticks have the characteristics of weather resistance, oil resistance, no static electricity, good secondary processability and the like. In the production process of the cigarette holder filter stick, a plasticizer (glyceryl triacetate) is required to be added to increase the hardness and elasticity of the filter stick, improve the processing performances of the filter stick such as cutting and the like, and meet the sensory requirements of consumers.

The filter stick product directly using the hot melt adhesive process after the new 'standard' is implemented has the problems of cracking (glue opening), cutting, line opening and the like in the storage process.

The inventor finds that the problem is caused by the fact that certain raw materials which cannot meet the 'standard' sanitary condition are removed from the hot melt adhesive in the synthesis process due to the implementation of the 'standard', so that the hot melt adhesive film is soaked, permeated and dissolved by the plasticizer in the storage process of the filter rod, and finally the bonding is failed.

Therefore, the core to solve the above problems is to improve the plasticizer resistance of the hot melt adhesive. Meanwhile, the base material bonded by the hot melt adhesive of the filter stick is high-transparency forming paper, and belongs to a porous material which is easy to bond, so that the requirement on the bonding performance of the hot melt adhesive is not high.

The invention obtains the high triacetin-resistant hot melt adhesive by selecting a specific low surface energy modifier as a modifier.

According to the first aspect of the invention, the invention discloses a hot melt adhesive for filter sticks, which is mainly prepared from the following raw materials in percentage by weight: 20-60% of main resin, 5-25% of wax, 5-35% of modifier, 20-60% of tackifying resin and 0.1-3.0% of auxiliary agent; wherein the modifier is alkyl siloxane and/or polyfluoroalkylalkoxysilane; the alkyl carbon atom number of the alkyl siloxane is 8-30, the boiling point of the alkyl siloxane is more than 150 ℃, and the surface energy of the alkyl siloxane is less than 30 mN/m; the polyfluoroalkylalkoxysilane has a polyfluoroalkyl group having 8 to 30 carbon atoms, an alkoxy group having 1 or 2 carbon atoms, a boiling point of more than 150 ℃, and a surface energy of less than 30 mN/m.

Modifying agent

The modifier is alkyl siloxane and/or polyfluoroalkylalkoxysilane, namely the modifier is alkyl siloxane, or the modifier is polyfluoroalkylalkoxysilane, or the modifier is alkyl siloxane and polyfluoroalkylalkoxysilane. Preferably a combination of an alkylsiloxane and a polyfluoroalkylalkoxysilane.

The alkyl siloxane includes but is not limited to one or more mixtures of dodecyl siloxane and hexadecyl hepta siloxane, the number of alkyl carbon atoms is between 8 and 30 (such as 8, 9, 10, 12, 13, 14, 15, 16, 18, 20, 22, 24, 25, 26, 28 and 30), the boiling point of the alkyl siloxane is more than 150 ℃, and the surface energy is less than 30 mN/m.

Polyfluoroalkylalkoxysilanes include, but are not limited to, one or more mixtures of tridecafluorooctyltrimethoxysilane, tridecafluorooctyltriethoxysilane, heptadecafluorodecyltrimethoxysilane, and heptadecafluorodecyltriethoxysilane, with the number of carbon atoms in the polyfluoroalkyl group being between 8 and 30 (e.g., 8, 9, 10, 12, 13, 14, 15, 16, 18, 20, 22, 24, 25, 26, 28, 30), the number of carbon atoms in the alkoxy group being 1 or 2, and the polyfluoroalkylalkoxysilane having a boiling point greater than 150 ℃ and a surface energy of less than 30 mN/m.

Preferably, the number of carbon atoms in the polyfluoroalkyl group is between 10 and 20, and the polyfluoroalkylalkoxysilane has a boiling point greater than 150 ℃ and a surface energy less than 25 mN/m.

Typical but non-limiting weight percentages of modifiers are, for example, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 15%, 16%, 18%, 20%, 22%, 24%, 25%, 26%, 28%, 30%, 32%, 34%, or 35%.

The surface energy of the glyceryl triacetate is 31.36mN/m, while the surface energy of the hot melt adhesive is generally between 35 and 50mN/m, i.e., the penetration and dissolution of the glyceryl triacetate to the hot melt adhesive is generally a spontaneous process. Therefore, in order to improve the triacetin resistance of the hot melt adhesive, it is necessary to reduce the surface energy of the hot melt adhesive to at least 30mN/m or less.

Since hot melt adhesives are all physical blends, we prefer to consider thermoplastic low surface energy materials. The surface energy of the polytetrafluoroethylene is 18-20mN/m, and is the lowest surface energy substance in all high molecular substances. But the melting point is too high to reach more than 200 ℃, and the non-hot melt adhesive can not be applied at the temperature of between 100 ℃ and 200 ℃. When the emulsion type polytetrafluoroethylene is applied, the process treatment is complicated, the mixing is not uniform, and the emulsion type polytetrafluoroethylene cannot be used. We therefore sought to select next alkylsiloxanes and fluoroalkylalkoxysilanes having a surface energy of from 19 to 23 mN/m. In the process of applying fluoroalkyl alkoxy silane, we find that the surface energy of the hot melt adhesive film gradually becomes lower in the storage process, which shows that siloxane gradually moves to the surface after the adhesive film is bonded, reacts with moisture in the air, and extends the chain, and finally a protective layer is formed on the surface of the hot melt adhesive, so that the characteristic of glyceryl triacetate resistance is completely realized. Meanwhile, when the siloxane and the fluoroalkyl alkoxy silane are used simultaneously, compared with the single use, under the condition that the using amount is almost the same, the mixed use effect is optimal, and the contact angle with the glyceryl triacetate is the largest, namely the compatibility is the worst. Therefore, the two different modifiers have good intermiscibility and certain synergistic effect.

The surface energy of the alkyl siloxane and the fluoroalkyl alkoxy silane can reach less than 20mN/m at least, and is the lowest of all the hot melt adhesive raw materials. Meanwhile, the invention has the effects of migrating surface chain extension and curing, and is the core content of the invention. The index requirements for the number of carbon atoms and boiling point are the prevention of pyrolysis and volatilization during processing and use. Meanwhile, although the silicon-oxygen bond is contacted with moisture but the chain extension is inevitable, the contact with the moisture is avoided as much as possible in the production, use and storage processes, and meanwhile, when the proportion is in a reasonable range, the increase rate of the melt viscosity after the chain extension is in the reasonable range.

Host resin

In a preferred embodiment, the host resin is one or more of a mixture of 1-octene and ethylene copolymer resin (POE), polyvinyl acetate and ethylene copolymer resin (EVA), polyethylene resin (PE), polypropylene resin (PP), polyethylene and propylene copolymer resin (PEPP);

the melt viscosity (175 ℃) of the main body resin is 6000-100000mPa.s (such as 7000, 8000, 10000, 50000, 80000mPa.s), the melt index (2.16kg,190 ℃) is 100-1200g/10min (such as 200, 500, 800, 1000g/10min), and the surface energy is less than 35 mN/m.

Preferably, the melt viscosity (175 ℃) of the host resin is 6000-50000mPa.s, the melt index (2.16kg,190 ℃) is 400-1200g/10min, and the surface energy is less than 30 mN/m.

Typical but non-limiting weight percentages of the host resin are, for example, 20%, 22%, 24%, 25%, 26%, 28%, 30%, 32%, 34%, 35%, 38%, 40%, 42%, 45%, 46%, 48%, 50%, 55%, or 58%.

The surface energy of the host resins is lower than 35mN/m, and the partial surface energy of the host resins is lower than 30 mN/m. The POE surface energy is the lowest, and PE, PP, PEPP and EVA are the second, but the surface energy of some EVA can reach below 30 mN/m. The setting of the technical index of the surface energy is the basic material for preparing the hot melt adhesive with low surface energy, environmental protection, high triacetin resistance and high durable adhesion.

Wax

In a preferred embodiment, the wax comprises one or more mixtures of fischer-tropsch wax, microcrystalline wax, polyethylene wax, paraffin wax;

the wax has a ring and ball softening point of 60-130 deg.C (e.g. 70, 80, 100, 120 deg.C), and a surface energy of less than 35 mN/m;

preferably, the wax has a ring and ball softening point in the range of 70-90 ℃ and a surface energy of less than 30 mN/m.

Typical but non-limiting weight percentages of waxes are, for example, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 15%, 16%, 18%, 20%, 22%, 24%, 25%.

The surface energy of the wax parts is lower than 30 mN/m. The low softening point is selected to be close to the softening point of the main resin, and the processing temperature can be reduced by using the low softening point tackifier resin.

Tackifying resins

In a preferred embodiment, the tackifying resin comprises one or more mixtures of rosin and derivatives thereof, terpene resins and derivatives thereof, petroleum resins and derivatives thereof, polymeric cyclopentadiene and hydrides thereof, styrene polymers, mixtures of alpha-methylstyrene and vinyltoluene polymers.

The tackifying resin has a ring and ball softening point of 60-130 ℃ (e.g., 70, 80, 100, 120 ℃) and a surface energy of less than 50 mN/m.

Preferably, the tackifying resin has a ring and ball softening point of 70-100 ℃ and a surface energy of less than 45 mN/m.

Typical but non-limiting weight percentages of tackifying resins are, for example, 20%, 22%, 24%, 25%, 26%, 28%, 30%, 32%, 34%, 35%, 38%, 40%, 42%, 45%, 46%, 48%, 50%, 55%, 58%, or 60%.

The surface energies of the above-mentioned several tackifying resins are the highest among all materials of hot melt adhesives, so that the selection of an appropriate tackifying resin has a significant impact on the end result. The surface energy of the hydrogenated petroleum resin is lower and can reach about 40mN/m at the lowest. The softening point is also selected to lower the processing temperature.

Auxiliary agent

In a preferred embodiment, the adjuvant comprises an antioxidant adjuvant comprising pentaerythritol tetrakis [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate (1010) and/or 2, 6-di-tert-butyl-p-cresol (BHT).

Typical but non-limiting percentages by weight of auxiliaries are, for example, 0.2%, 0.5%, 0.8%, 1.0%, 1.5%, 1.8%, 2.0%, 2.5%, 3.0%.

Preferably, the antioxidant auxiliary agent is pentaerythritol tetrakis [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ] (1010) and 2, 6-di-tert-butyl-p-cresol (BHT). The two have synergistic effect when used together.

The hot melt adhesive for the filter stick is mainly composed, namely the hot melt adhesive for the filter stick can comprise other components besides the main body resin, the wax, the modifier, the tackifying resin and the auxiliary agent, wherein the sum of the main body resin, the wax, the modifier, the tackifying resin, the auxiliary agent and optionally other components is 100%.

The hot melt adhesive mainly comprises main resin, wax, a modifier, tackifying resin and an auxiliary agent, and solves the problems of poor triacetin resistance and finally bonding failure caused by overhigh surface energy in the hot melt adhesive technology for filter stick production in the existing cigarette industry by adopting the specific modifier with low surface energy and high boiling point and the universal hot melt adhesive for blending. The hot melt adhesive has excellent glycerol acetate resistance, is applied to the production of filter sticks in the cigarette industry, and is suitable for popularization and application.

In a preferred embodiment, the hot melt adhesive is mainly prepared from the following raw materials in percentage by weight: 25-50% of main resin, 8-20% of wax, 8-25% of modifier, 20-50% of tackifying resin and 0.1-1.0% of auxiliary agent.

The optimized scheme balances the proportion of each component, particularly greatly reduces the upper limit of the content of each component, and enables the surface energy, the melt viscosity and the like to reach a balanced state.

According to a second aspect of the invention, a preparation method of the hot melt adhesive for the filter stick is provided, which comprises the following steps:

preferably, the method specifically comprises the following steps:

(1) adding the raw materials (except the modifier) into a container in sequence according to the raw material metering proportion, starting heating, starting stirring after the material temperature reaches 120-130 ℃, wherein the stirring speed is 20-50r/min, the vacuum is 2h, and the vacuum degree is between-0.09 MPa and-0.1 MPa.

(2) Stopping stirring, removing vacuum, adding modifier, and stirring (20-50r/min) for 60 min; cooling to 100 ℃ and 120 ℃, discharging, granulating by a steel belt, and carrying out vacuum packaging.

The purpose of the vacuum 2h in the step (1) is to remove trace moisture in the materials, and the steel belt granulation is selected in the step (2) instead of underwater granulation, so that the moisture is avoided.

According to a third aspect of the invention, the application of the hot melt adhesive for the filter stick in the preparation of cigarette filter stick products is provided.

The preparation method disclosed by the invention can be used for obtaining the environment-friendly, low-surface-energy and high-triacetin-resistance hot melt adhesive, can be used in the field of filter stick bonding in the cigarette industry, and is suitable for popularization and application.

The invention is further illustrated by the following examples. The materials in the examples are prepared according to known methods or are directly commercially available, unless otherwise specified.

Examples 1 to 3 and comparative examples 1 to 3

A preparation method of the environment-friendly hot melt adhesive for the filter stick comprises the following steps:

examples 1-3 are hot melt adhesives of different materials with different types of silicones.

Comparative examples 1-3 are each typical hot melt adhesives.

TABLE 1 EXAMPLES 1-3 AND COMPARATIVE EXAMPLE MATERIALS DATA TABLE

The production method and the process are as follows:

Experimental data: basic performance testing and computer experimental data

TABLE 2 basic Performance data and machine Endurance data for examples 1-3 and comparative examples 1-3

Comparative example 4

The formulation was the same as in example 1, except that dimethyl siloxane was used instead of dodecyl siloxane. In the high temperature mixing stage, bubbles appear in the colloid to varying degrees. After bubbles in the colloid are removed by a vacuum method, a thin oil layer appears on the surface obviously, which indicates that the dimethyl siloxane is poor in compatibility with the colloid. The contact angle of the colloid was measured, and the result showed 59.6, and no modification was achieved.

Comparative example 5

The low molecular weight polytetrafluoroethylene is melted at 280 ℃ by white oil to prepare a uniform solution for later use. The hot melt was prepared as in example 3, using the homogeneous solution described above in place of all the tridecafluorooctyltriethoxysilane. However, the hot melt adhesive has extremely poor machine performance, the adhesive accumulation appears at the adhesive spraying port after the machine is started for half a minute, and the adhesive spraying port is blocked in about 1 minute. It is explained that although white oil is used for melting polytetrafluoroethylene, the polytetrafluoroethylene is not completely melted in the hot melt adhesive, but only is melted and expanded in the hot melt adhesive, and meanwhile, the molecular weight is too large, so that adhesive accumulation and blockage occur.

Therefore, the alkyl siloxane and/or fluoroalkyl alkoxy silane are/is added as the modifier through screening, so that the hot melt adhesive has excellent glycerol acetate resistance, the problems of opening (glue opening), cutting, line opening and the like of a filter stick product prepared by directly using a hot melt adhesive process are avoided, and the glycerol acetate resistance effect of the alkyl siloxane and fluoroalkyl alkoxy silane is optimal under the condition that the using amounts are almost the same.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The method disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the description of the method part.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. The hot melt adhesive for the filter stick is characterized by mainly being prepared from the following raw materials in percentage by weight: 20-60% of main resin, 5-25% of wax, 5-35% of modifier, 20-60% of tackifying resin and 0.1-3.0% of auxiliary agent;

the modifier is alkyl siloxane and/or polyfluoroalkylalkoxysilane;

the polyfluoroalkyl alkoxysilane has a polyfluoroalkyl group carbon number of 8 to 30, an alkoxy carbon number of 1 or 2, a boiling point of more than 150 ℃, and a surface energy of less than 30 mN/m;

wherein the main resin comprises one or more of 1-octene and ethylene copolymer resin, polyvinyl acetate and ethylene copolymer resin, polyethylene resin, polypropylene resin or polyethylene and propylene copolymer resin;

wherein the wax comprises one or more of Fischer-Tropsch wax, microcrystalline wax, polyethylene wax or paraffin wax.

2. The hot melt adhesive for filter rods according to claim 1, wherein the alkyl siloxane comprises one or more of dodecyl siloxane and hexadecyl heptasiloxane.

3. The hot melt adhesive for filter rods according to claim 1, wherein the polyfluoroalkylalkoxysilane comprises one or more of tridecafluorooctyltrimethoxysilane, tridecafluorooctyltriethoxysilane, heptadecafluorodecyltrimethoxysilane or heptadecafluorodecyltriethoxysilane.

4. The hot melt adhesive for filter rods according to claim 1, wherein the polyfluoroalkylalkoxysilane has a polyfluoroalkyl group having 10 to 20 carbon atoms and an alkoxy group having 1 or 2 carbon atoms, and has a boiling point of more than 150 ℃ and a surface energy of less than 25 mN/m.

5. The hot melt adhesive for filter rods according to any one of claims 1 to 4, wherein the hot melt adhesive for filter rods is mainly prepared from the following raw materials in percentage by weight: 25-50% of main resin, 8-20% of wax, 8-25% of modifier, 20-50% of tackifying resin and 0.1-1.0% of auxiliary agent.

6. The hot melt adhesive for filter rods according to any one of claims 1 to 4, wherein the melt viscosity of the main resin at 175 ℃ is 2000-100000mPa.s, the melt index at 190 ℃ is 50-1200g/10min, and the surface energy is less than 35 mN/m.

7. The hot melt adhesive for filter sticks according to any one of claims 1 to 4, wherein the melt viscosity of the main body resin at 175 ℃ is 6000-50000mPa.s, 2.16kg, the melt index at 190 ℃ is 400-1200g/10min, and the surface energy is less than 30 mN/m.

8. A hot melt adhesive for filter rods according to any one of claims 1 to 4, wherein the ring and ball softening point of the wax is 60 to 130 ℃, and the surface energy is less than 35 mN/m.

9. A hot melt adhesive for filter rods according to any one of claims 1 to 4, wherein the ring and ball softening point of the wax is 70-90 ℃, and the surface energy is less than 30 mN/m.

10. A hot melt adhesive for filter rods according to any one of claims 1 to 4, wherein the tackifying resin comprises one or more of rosin and derivatives thereof, terpene resin and derivatives thereof, petroleum resin and derivatives thereof, polymerized cyclopentadiene and hydrides thereof, styrene polymers, and a-methylstyrene and vinyltoluene polymer mixtures.

11. A hot melt adhesive for filter rods according to any one of claims 1 to 4, wherein the ring-and-ball softening point of the tackifying resin is 60 to 130 ℃, and the surface energy is less than 50 mN/m.

12. A hot melt adhesive for filter rods according to any one of claims 1 to 4, wherein the ring-and-ball softening point of the tackifying resin is 70-100 ℃, and the surface energy is less than 45 mN/m.

13. The hot melt adhesive for filter rods according to any one of claims 1 to 4, wherein the auxiliary agent comprises an antioxidant.

14. The hot melt adhesive for filter rods according to claim 13, wherein the antioxidant comprises pentaerythritol tetrakis [ β - (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ] and/or 2, 6-di-tert-butyl-p-cresol.

15. A method for preparing the hot melt adhesive for the filter rods according to any one of claims 1 to 14, which is characterized by comprising the following steps:

and mixing the main resin, the wax, the modifier, the tackifying resin and the auxiliary agent according to the raw material metering ratio to obtain the hot melt adhesive for the filter rod.

16. A method for preparing the hot melt adhesive for the filter rods according to any one of claims 1 to 14, which is characterized by comprising the following steps:

17. Use of the hot melt adhesive for filter rods according to any one of claims 1 to 14 in preparation of cigarette filter rod products.