Reactive hot melt adhesive as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of hot melt adhesives, and particularly relates to a reactive hot melt adhesive as well as a preparation method and application thereof. The reactive hot melt adhesive is prepared from the following raw material components in parts by mass: 15 to 30 parts of dimer acid modified polyester polyol, 5 to 15 parts of isocyanate, 10 to 20 parts of a thermoplastic elastomer, 35 to 60 parts of tackifying resin, 0.05 to 0.5 part of an antioxidant, 0.05 to 0.3 part of a de-foaming agent, 0.01 to 0.1 part of a stabilizer and 0.01 to 0.3 part of a catalyst. Through the combined action of all the components, the reactive hot melt adhesive has excellent initial bonding strength, meanwhile, the bonding compatibility to low-polarity and high-polarity base materials is good, the thermal stability is excellent, and the high-temperature and high-humidity resistance is excellent after curing.

Description

Technical Field

[0001] The present application belongs to the technical field of hot melt adhesives, and in particular, relates to a reactive hot melt adhesive and a preparation method and application thereof. Background Art

[0002] Hot melt adhesive is a thermoplastic polymer adhesive. It melts and applies in a certain temperature range, and then solidifies through natural cooling to form a quick bonding and positioning between the substrates to be bonded. Compared with other hot melt adhesives, hot melt adhesive has the advantages of being solvent-free, high initial adhesion strength, easy to store and transport, and able to adapt to fast industrial assembly line operations, and is widely used in various industries.

[0003] Hot melt adhesives are divided into reactive hot melt adhesives and non-reactive hot melt adhesives. Among them, non-reactive hot melt adhesives are a plastic adhesive. Within a certain temperature range, its physical state changes with temperature, while its chemical properties remain unchanged. The force between it and the bonding substrate is mainly the van der Waals force, and the bonding strength is insufficient. In addition, due to its own characteristics, the glue has poor heat resistance and is prone to bonding failure in high temperature or high humidity environments. Reactive hot melt adhesives are an improved product of traditional hot melt adhesives. By grafting reactive active groups on the molecular structure of the hot melt adhesive, the glue produces initial bonding strength through changes in physical state with temperature after application. The subsequent active groups can chemically react to form a cross-linked network structure. Under the combined action of physical bonding and chemical bonding, the reactive hot melt adhesive has higher bonding strength and is not easy to fail in a hot and humid environment.

[0004] At present, there are three main types of reactive hot melt adhesives, including moisture-curing reactive polyurethane hot melt adhesives, UV-moisture dual-solid reactive hot melt adhesives, and moisture-curing reactive polyolefin hot melt adhesives. However, these three types of reactive hot melt adhesives have problems such as low initial bonding strength and efficiency, and poor bonding compatibility with low-polarity and high-polarity substrates. Summary of the invention

[0005] The purpose of the present application is to provide a reactive hot melt adhesive and its preparation method and application, aiming to solve to a certain extent the problems of reactive hot melt adhesive having low initial bonding strength and efficiency, and poor bonding compatibility with low-polarity and high-polarity substrates.

[0006] In order to achieve the above application purpose, the technical solution adopted in this application is as follows:

[0007] In a first aspect, the present application provides a reactive hot melt adhesive, comprising the following raw material components in parts by mass:

[0008] 15 to 30 parts of dimer acid modified polyester polyol,

[0009] 5 to 15 parts of isocyanate,

[0010] Thermoplastic elastomer 10 to 20 parts,

[0011] 35 to 60 parts of tackifying resin,

[0012] 0.05 to 0.5 parts of antioxidant,

[0013] Defoaming agent 0.05 to 0.3 parts,

[0014] Stabilizer 0.01 to 0.1 parts,

[0015] Catalyst 0.01 to 0.3 parts.

[0016] In some possible implementations, the hydroxyl value of the dimer acid-modified polyester polyol is 35 mgKOH / g to 80 mgKOH / g.

[0017] In some possible implementations, the dimer acid-modified polyester polyol includes a main chain and at least two side chains, wherein the main chain has 30 to 50 carbon atoms, and a single side chain has 8 to 15 carbon atoms.

[0018] In some possible implementations, the dimer acid-modified polyester polyol is selected from at least one of Priplast 3192, Priplast 3190, DA-2110, DA-21, BY 3026, and BY 3022.

[0019] In some possible implementations, the content of isocyanate groups in the reactive hot melt adhesive is 1 wt % to 2.5 wt %.

[0020] In some possible implementations, the thermoplastic elastomer includes a styrene block copolymer.

[0021] In some possible implementations, the tackifying resin includes a solid tackifying resin and a liquid tackifying resin.

[0022] In some possible implementations, the raw material components of the reactive hot melt adhesive include 30 to 45 parts of the solid tackifying resin and 5 to 15 parts of the liquid tackifying resin.

[0023] In some possible implementations, the softening point of the solid tackifying resin is 80°C to 130°C.

[0024] In some possible implementations, the liquid tackifying resin is in liquid state at room temperature.

[0025] In some possible implementations, the isocyanate is selected from at least one of toluene diisocyanate isomers, diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, carbodiimide-modified diphenylmethane-4,4'-diisocyanate, naphthalene-1,4-diisocyanate, xylene diisocyanate, and 1,4-phenylene diisocyanate.

[0026] In some possible implementations, the styrene block copolymer is selected from at least one of ethylene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-ethylene-butylene-styrene, and styrene-ethylene-propylene-styrene.

[0027] In some possible implementations, the liquid tackifying resin is selected from at least one of aliphatic resin, liquid rosin tackifying resin, liquid monomer tackifying resin, aromatic resin, and liquid aromatic resin.

[0028] In some possible implementations, the solid tackifying resin is selected from at least one of aliphatic resins, alicyclic resins, aromatic resins, aliphatic / aromatic copolymer resins, C5 hydrogenated petroleum resins, and C9 hydrogenated petroleum resins.

[0029] In some possible implementations, the antioxidant is selected from at least one of antioxidant 245 , antioxidant 1010 , antioxidant 1076 , antioxidant 1098 and antioxidant 1024 .

[0030] In some possible implementations, the catalyst is selected from at least one of dibutyltin dilaurate, stannous octoate, tetramethylethylenediamine, triethylenediamine, bismorpholinyl diethyl ether and dimorpholine triethyl ether.

[0031] In some possible implementations, the defoaming agent is a non-silicone polymer defoaming agent.

[0032] In some possible implementations, the stabilizer is selected from at least one of phosphoric acid, benzoyl chloride, benzoic acid and polyphosphoric acid.

[0033] In a second aspect, the present application provides a method for preparing a reactive hot melt adhesive, comprising the following steps:

[0034] In a dry inert atmosphere, 15 to 30 parts of dimer acid-modified polyester polyol, 5 to 15 parts of isocyanate, 10 to 20 parts of thermoplastic elastomer, 35 to 60 parts of tackifying resin, 0.05 to 0.5 parts of antioxidant, 0.05 to 0.3 parts of defoaming agent, 0.01 to 0.1 parts of stabilizer and 0.01 to 0.3 parts of catalyst are mixed to prepare a reactive hot melt adhesive.

[0035] In some possible implementations, the inert atmosphere includes at least one of nitrogen, argon, and helium.

[0036] In some possible implementations, the mixing step includes:

[0037] The tackifying resin, the thermoplastic elastomer, the antioxidant, the defoaming agent and the stabilizer are first mixed and melted to obtain a first mixture;

[0038] Performing a second mixing and melting of the first mixture and the dimer acid-modified polyester polyol to obtain a second mixture;

[0039] After the second mixture and the isocyanate are mixed and reacted, the catalyst is added, and the reaction-type hot melt adhesive is obtained after degassing treatment.

[0040] In some possible implementations, the temperature condition of the first mixed melting is 120°C to 200°C.

[0041] In some possible implementations, the temperature condition of the second mixed melting is 100°C to 130°C.

[0042] In some possible implementations, the water content in the second mixture is less than 0.05 wt %.

[0043] In some possible implementations, the temperature condition of the mixed reaction is 95° C. to 115° C., and the duration is 1.5 h to 2 h.

[0044] In some possible implementations, the degassing treatment conditions include: in an inert atmosphere with a vacuum degree of -0.05 MPa to 0.095 MPa, heating to 160° C. to 180° C. and stirring for degassing for 30 min to 50 min.

[0045] The reactive hot melt adhesive and / or the reactive hot melt adhesive prepared by the preparation method are used in at least one of the following fields: packaging industry, shoe fabrics, electronic and electrical manufacturing industry, automobile manufacturing industry, woodworking manufacturing industry, medical and health field, construction, new energy, machinery manufacturing, printing and binding, antistatic flocking, static electricity protection, daily maintenance, and handmade production.

[0046] The reactive hot melt adhesive provided in the first aspect of the present application adopts dimer acid-modified polyester polyol, which has excellent hydrolysis resistance and antioxidant performance compared with conventional polyester polyols and polyether polyols; as well as excellent heat resistance, acid and alkali resistance, solvent resistance and weather resistance, and has good bonding performance to low polar substrates. In addition, NCO-terminated prepolymers are generated by reacting isocyanate with dimer acid-modified polyester polyols, and the NCO group can react with moisture in the environment to generate allophanate, so that the prepolymer forms a cross-linked network structure, further improving the bonding strength and moisture and heat resistance of the hot melt adhesive. The combined effect of the polar groups and isocyanate group reactivity in the hot melt adhesive makes the hot melt adhesive have good bonding performance to polar substrates. Thermoplastic elastomers and tackifying resins make the raw rubber cohesive strength high and have certain hot melt pressure sensitivity, so that the hot melt adhesive forms a high-strength initial bonding. Antioxidants, defoamers, stabilizers and catalysts can further improve the stability and bonding efficiency of the hot melt adhesive. Through the joint action of various components, the reactive hot melt adhesive of the present application has excellent initial bonding strength, good bonding compatibility with low-polarity and high-polarity substrates, excellent thermal stability, and excellent resistance to high temperature and high humidity after curing.

[0047] The preparation method of the reactive hot melt adhesive of the present application is carried out in a dry inert atmosphere to avoid the influence of water, oxygen and other substances in the environment on the raw material components and the stability of the hot melt adhesive. The reactive hot melt adhesive can be prepared by mixing the raw material components of the formula. The preparation process is simple and suitable for industrial large-scale production and application. The prepared reactive hot melt adhesive has excellent initial bonding strength, good bonding compatibility with low-polarity and high-polarity substrates, excellent thermal stability, and excellent resistance to high temperature and high humidity after curing.

[0048] The reactive hot melt adhesive provided in the present application has excellent initial bonding strength, good bonding compatibility with low-polarity and high-polarity substrates, excellent thermal stability, and excellent resistance to high temperature and high humidity after curing. Therefore, it can be widely used in the packaging industry, shoe fabrics, electronic and electrical manufacturing, automobile manufacturing, woodworking manufacturing, medical and health fields, construction, new energy, machinery manufacturing, printing and binding, anti-static flocking, static protection, daily maintenance, hand-made and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0050] Figure 1 It is a schematic flow chart of a method for preparing a reactive hot melt adhesive provided in an embodiment of the present application. DETAILED DESCRIPTION

[0051] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0052] In this application, the term "and / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0053] In this application, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b or c", or "at least one of a, b and c", can all represent: a, b, c, ab (i.e. a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively.

[0054] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution, some or all of the steps can be executed in parallel or sequentially, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0055] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "an" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0056] The weight of the relevant components mentioned in the embodiments of the present specification can not only refer to the specific content of each component, but also represent the proportional relationship between the weights of the components. Therefore, as long as the content of the relevant components in the embodiments of the present specification is proportionally enlarged or reduced, it is within the scope disclosed in the embodiments of the present specification. Specifically, the mass described in the embodiments of the present specification can be μg, mg, g, kg and other mass units known in the chemical industry.

[0057] The terms "first" and "second" are used only for descriptive purposes to distinguish objects such as substances from each other, and should not be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. For example, without departing from the scope of the embodiments of the present application, the first XX may also be referred to as the second XX, and similarly, the second XX may also be referred to as the first XX. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0058] At present, there are three main types of reactive hot melt adhesives, including moisture-curing reactive polyurethane hot melt adhesives, UV-moisture dual-solid reactive hot melt adhesives, and moisture-curing reactive polyolefin hot melt adhesives. However, each of these three types of adhesives has its own shortcomings, as follows:

[0059] Conventional moisture-curing reactive polyurethane hot melt adhesives are usually prepared from polyether polyols, crystalline polyester polyols and thermoplastic elastomers. Their initial bonding strength is provided by highly crystalline polyester polyols and thermoplastic elastomers. Due to the insufficient initial bonding strength, they often need to be maintained under pressure to achieve operational strength during use. The addition of pressure-maintaining jigs increases the application production cost; at the same time, the requirements for pressure-maintaining time also affect production efficiency. In addition, conventional reactive polyurethane hot melt adhesives are polar hot melt adhesives that have good adhesion to polar materials, but when bonding low-polarity substrates, the substrates must be pre-treated on the surface, which increases the production process.

[0060] UV-moisture dual-curable reactive hot melt adhesive introduces UV-curable and moisture-reactive monomers or active groups into the glue. When used, ultraviolet light radiation is used to achieve rapid partial cross-linking of the molecular chain to provide the initial bonding strength of the glue; subsequent cross-linking and curing are completed by reaction with moisture. Because its initial bonding strength relies on UV radiation, when hot melt adhesive is used in light-opaque or thick adhesive layers, UV light cannot reach or penetrate, making it difficult to achieve a quick bonding effect. In addition, ultraviolet radiation equipment needs to be added during use, which increases the cost to a certain extent.

[0061] Moisture-curing reactive polyolefin hot melt adhesive is a product in which hydrolyzable siloxane groups are introduced into the polyolefin main chain by grafting or copolymerization. Under the action of moisture, the siloxane groups are hydrolyzed and condensed to achieve moisture-curing function and produce chemical bonding. However, due to the low polarity of polyolefin hot melt adhesive itself, it is difficult to achieve high-strength bonding to high-polarity substrates.

[0062] In order to solve the problems of reactive hot melt adhesives, such as low initial bonding strength and efficiency, and poor bonding compatibility with low-polarity and high-polarity substrates.

[0063] In a first aspect, an embodiment of the present application provides a reactive hot melt adhesive, which comprises the following raw material components in parts by mass:

[0064] 15 to 30 parts of dimer acid modified polyester polyol,

[0065] 5 to 15 parts of isocyanate,

[0066] Thermoplastic elastomer 10 to 20 parts,

[0067] 35 to 60 parts of tackifying resin,

[0068] 0.05 to 0.5 parts of antioxidant,

[0069] Defoaming agent 0.05 to 0.3 parts,

[0070] Stabilizer 0.01 to 0.1 parts,

[0071] Catalyst 0.01 to 0.3 parts.

[0072] The reactive hot melt adhesive provided in the first aspect of the embodiment of the present application adopts dimer acid-modified polyester polyol, which has excellent hydrolysis resistance and antioxidant performance compared with conventional polyester polyols and polyether polyols; as well as excellent heat resistance, acid and alkali resistance, solvent resistance and weather resistance, and has good bonding performance to low polar substrates. In addition, NCO-terminated prepolymers are generated by reacting isocyanate with dimer acid-modified polyester polyols, and the NCO group can react with moisture in the environment to generate allophanate, so that the prepolymer forms a cross-linked network structure, further improving the bonding strength and moisture and heat resistance of the hot melt adhesive. The combined effect of the polar groups and isocyanate group reactivity in the hot melt adhesive makes the hot melt adhesive have good bonding performance to polar substrates. Thermoplastic elastomers and tackifying resins make the raw rubber cohesive strength high and have a certain hot melt pressure sensitivity, so that the hot melt adhesive forms a high-strength initial bonding. Antioxidants, defoamers, stabilizers and catalysts can further improve the stability and bonding efficiency of the hot melt adhesive. Through the joint action of various components, the reactive hot melt adhesive of the embodiment of the present application has excellent initial bonding strength, good bonding compatibility with low-polarity and high-polarity substrates, excellent thermal stability, and excellent resistance to high temperature and high humidity after curing.

[0073] The reactive hot melt adhesive of the embodiment of the present application has excellent initial bonding strength, and after application, it is cured by moisture, and the hot melt adhesive has reliable moisture and heat resistance bonding performance after moisture curing. The weight fraction of dimer acid-modified polyester polyol in the hot melt adhesive is 15 to 30 parts, isocyanate 5 to 15 parts, thermoplastic elastomer 10 to 20 parts, tackifying resin 35 to 60 parts, antioxidant 0.05 to 0.5 parts, defoamer 0.05 to 0.3 parts, stabilizer 0.01 to 0.1 parts, catalyst 0.01 to 0.3 parts. Among them, dimer acid-modified polyester polyol reacts with isocyanate to synthesize polyurethane prepolymer, which can achieve cross-linking with moisture curing reaction after application, thereby improving the bonding strength to the substrate and the colloid strength. When the content of dimer acid-modified polyester polyol is too low, the components of the hot melt adhesive that can react with moisture are reduced, which will reduce the bonding strength and heat resistance of the hot melt adhesive after curing. At the same time, the prepolymer obtained by the reaction of dimer acid-modified polyester polyol and isocyanate has low viscosity at high temperature. Reducing the dosage will cause the viscosity of the hot melt adhesive to increase, which is not conducive to the application of glue. When the content of dimer acid-modified polyester polyol is too high, the prepolymer will extend the open time and the initial cohesion will be low, which will cause the initial bonding strength of the hot melt adhesive to decrease and reduce the rapid positioning ability. The prepolymer will undergo molecular self-polymerization under high temperature conditions. Excessive content in the hot melt adhesive will reduce the viscosity stability of the hot melt adhesive at the use temperature. Thermoplastic elastomers are high molecular polymers. Adding them to the system is beneficial to improving the initial cohesive strength of the glue and thus improving the initial adhesion strength. Three-way elastomers are high molecular polymers. Adding too much will cause the viscosity of the hot melt adhesive to rise sharply. Too high or too low content of tackifying resin will affect the adhesion of the hot melt adhesive. Too high or too low content of components such as antioxidants, defoamers, stabilizers, etc. will affect the stability of the hot melt adhesive.

[0074] In some possible implementations, the reactive hot melt adhesive, in terms of weight, in the raw material components, the weight of the dimer acid-modified polyester polyol can be 15 parts, 20 parts, 25 parts, 30 parts, etc., the weight of the isocyanate can be 5 parts, 8 parts, 10 parts, 12 parts, 15 parts, etc., the weight of the thermoplastic elastomer can be 10 parts, 12 parts, 15 parts, 18 parts, 20 parts, etc., the weight of the tackifier resin can be 35 parts, 40 parts, 45 parts, 50 parts , 55 parts, 60 parts, etc., the mass parts of antioxidants can be 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, etc., the mass parts of defoamers can be 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, etc., the mass parts of stabilizers can be 0.01 parts, 0.05 parts, 0.08 parts, 0.1 parts, etc., the mass parts of catalysts can be 0.01 parts, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, etc.

[0075] In some possible implementations, the hydroxyl value of the dimer acid-modified polyester polyol is 35 mgKOH / g to 80 mgKOH / g, and specifically can be 35 mgKOH / g, 40 mgKOH / g, 45 mgKOH / g, 50 mgKOH / g, 55 mgKOH / g, 60 mgKOH / g, 65 mgKOH / g, 70 mgKOH / g, 75 mgKOH / g, 80 mgKOH / g, and other typical but non-limiting arbitrary point values ​​or interval values ​​between any two point values. In this case, the polyacid-modified polyester polyol is selected from a polyester polyol synthesized from a dimer acid monomer in the main chain. When the hydroxyl value of the polyacid-modified polyester polyol is within the range of 35 mgKOH / g to 80 mgKOH / g, the hydroxyl value, as an important performance index of the polyester polyol, directly reflects the content of hydroxyl groups in its molecule. Polyester polyols with higher hydroxyl values ​​have relatively more hydroxyl groups in their molecules. These hydroxyl groups can react with other components in the hot melt adhesive during the preparation process of the hot melt adhesive to form a cross-linked structure, thereby significantly increasing the viscosity of the hot melt adhesive. The increase in viscosity helps to enhance the bonding strength of the hot melt adhesive, so that it can obtain good bonding effects on various substrates. In addition, during the preparation of the hot melt adhesive, the hydroxyl value of the dimer acid-modified polyester polyol will also affect the reaction rate and curing time. Polyester polyols with moderate hydroxyl values ​​can react with other components in the hot melt adhesive at an appropriate rate to avoid the hot melt adhesive being unstable due to too fast a reaction, or the production efficiency being affected by too slow a reaction. At the same time, the appropriate hydroxyl value also helps to adjust the curing time, so that the hot melt adhesive can form a stable cross-linked network during the curing process, thereby obtaining better physical properties and weather resistance. In addition, the hydroxyl value of dimer acid-modified polyester polyols also has an important influence on its thermal stability and weather resistance. Polyester polyols with higher hydroxyl values ​​have more hydroxyl groups in their molecular chains, and these hydroxyl groups can form more cross-linking points with other components in the hot melt adhesive, thereby enhancing the thermal stability of the hot melt adhesive. Under high temperature conditions, these crosslinking points can maintain the viscosity of the hot melt adhesive and prevent it from oxidation and degradation. At the same time, polyester polyols with moderate hydroxyl values ​​can also help improve the weather resistance of the hot melt adhesive, allowing it to maintain stable performance in various harsh environments.

[0076] In some possible implementations, the dimer acid-modified polyester polyol includes a main chain and at least two side chains, wherein the number of carbon atoms in the main chain is 30 to 50, and the number of carbon atoms in a single side chain is 8 to 15. In this case, the polarity of the dimer acid polyester polyol is lower than that of the general aliphatic polyester polyol, which improves the compatibility with thermoplastic elastomers and the bonding strength to polar substrates; the bulky alkyl side chains on the main chain have a protective function, allowing the hot melt adhesive to obtain good hydrolysis stability and weather resistance. Exemplarily, in the dimer acid-modified polyester polyol, the number of carbon atoms in the main chain can be 30, 35, 40, 45, 50, etc., which are typical but not limiting values, or an interval value between any two values, and the number of carbon atoms in a single side chain can be 8, 9, 10, 11, 12, 13, 14, 15, etc., which are typical but not limiting values, or an interval value between any two values.

[0077] In some possible implementations, the dimer acid modified polyester polyol is selected from at least one of Priplast 3192, Priplast 3190, DA-2110, DA-21, BY 3026, and BY 3022. These dimer acid modified polyester polyols all have excellent hydrolysis resistance and oxidation resistance; as well as excellent heat resistance, acid and alkali resistance, solvent resistance, and weather resistance, and have good adhesion to low-polarity substrates. Among them, BY3026 and BY 3022 are a series of low-viscosity, flowable, ultra-high-performance dimer acid modified polyols. The polyester diol has very excellent high and low temperature resistance, flex resistance, substrate wetting, improved adhesion, water resistance, hydrolysis resistance, and UV resistance, and has excellent water resistance and excellent hydrolysis resistance; excellent oxidation resistance, good acid and alkali resistance, heat resistance, and weather resistance; good flexibility and tensile properties. Priplast 3192 and Priplast 3190 series dimer acid modified polyester polyols have excellent hydrolysis resistance, can maintain stable performance in humid environments, have better fluidity and plasticity during processing, and have excellent mechanical properties, which can meet the needs of various application scenarios. DA-2110 and DA-21 series dimer acid modified polyester polyols have excellent water resistance, excellent UV resistance, excellent antioxidant properties, good heat resistance, weather resistance and solvent resistance, as well as excellent cohesion and tensile strength.

[0078] In some possible implementations, the content of isocyanate groups in the reactive hot melt adhesive is 1wt% to 2.5wt%, specifically 1wt%, 1.5wt%, 2wt%, 2.5wt%, etc. In this case, the isocyanate groups can fully react with the dimer acid-modified polyester polyol to generate NCO-terminated prepolymers, and the NCO groups can react with moisture in the environment to generate allophanates, so that the prepolymer forms a cross-linked network structure, thereby improving the bonding strength and moisture and heat resistance of the hot melt adhesive. Through the combined action of the polar groups in the hot melt adhesive and the reactivity of the isocyanate groups, it has good bonding properties to polar substrates.

[0079] In some possible implementations, the isocyanate is selected from at least one of toluene diisocyanate (TDI) isomers, diphenylmethane-4,4'-diisocyanate (MDI), diphenylmethane-2,4'-diisocyanate (MDI), carbodiimide-modified diphenylmethane-4,4'-diisocyanate (C-MDI), naphthalene-1,4-diisocyanate (NDI), xylene diisocyanate (XDI), and 1,4-phenylene diisocyanate. In the above embodiments of the present application, the isocyanate can react with the dimer acid-modified polyester polyol to generate an NCO-terminated prepolymer, and the NCO group can react with moisture in the environment to generate an allophanate, so that the prepolymer forms a cross-linked network structure, thereby improving the bonding strength and moisture and heat resistance of the hot melt adhesive.

[0080] In some preferred embodiments, the isocyanate is selected from at least one of diphenylmethane-4,4'-diisocyanate (MDI), carbodiimide-modified diphenylmethane-4,4'-diisocyanate (C-MDI), and diphenylmethane-2,4'-diisocyanate (MDI). These isocyanates have better reactivity, can better improve the bonding strength and moisture and heat resistance of the hot melt adhesive, and have good bonding properties to polar substrates through the combined action of the polar groups and isocyanate group reactivity in the hot melt adhesive.

[0081] In some possible implementations, the thermoplastic elastomer includes a styrene block copolymer (SBC). In this case, a styrene block copolymer and a tackifying resin are used to make the raw rubber have high cohesive strength, have certain hot melt pressure sensitivity, and form a high-strength initial bond. Styrene block copolymers can provide strong cohesive force in hot melt adhesives, ensuring that the adhesive can firmly bond various materials after curing. At the same time, styrene block copolymers also give the hot melt adhesive a higher strength, so that it can withstand certain external forces without being easily broken. In addition, styrene block copolymers also have excellent heat resistance and can maintain stable performance at higher temperatures, thereby ensuring the reliability of hot melt adhesives in high temperature environments. In addition, the thermoplastic properties of SBC enable it to melt quickly and be evenly distributed on the substrate during the processing of hot melt adhesives. This helps to improve the processing performance of hot melt adhesives, making them easier to operate and apply. At the same time, the fluidity of SBC also helps to improve the permeability and wettability of hot melt adhesives, thereby enhancing the contact area and bonding effect between the adhesive and the adherend. Moreover, as a thermoplastic elastomer, SBC can improve the elasticity of hot melt adhesive to a certain extent, which enables the hot melt adhesive to have a certain flexibility and impact resistance after curing, thereby adapting to the bonding needs of different materials and shapes.

[0082] In some possible implementations, the styrene block copolymer is selected from at least one of ethylene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene-ethylene-butylene-styrene (hydrogenated SBS (SEBS)), and styrene-ethylene-propylene-styrene (hydrogenated SIS (SEPS)). These styrene block copolymers can enhance the cohesive strength and heat resistance of the hot melt adhesive, improve the processing performance and fluidity, optimize the elasticity of the hot melt adhesive, and enhance the weather resistance and aging resistance of the hot melt adhesive.

[0083] In some preferred embodiments, the styrene block copolymer is selected from at least one of ethylene-butadiene-styrene block copolymer (SBS) and styrene-isoprene-styrene block copolymer (SIS).

[0084] In some possible implementations, the tackifying resin includes a solid tackifying resin and a liquid tackifying resin. In this case, the hot melt adhesive contains an appropriate amount of solid tackifying resin and liquid tackifying resin at the same time, which can improve the compatibility, improve the bonding performance, heat resistance, processing performance and broaden the application field, and also has the advantages of economy and environmental protection. Specifically, the solid tackifying resin and the liquid tackifying resin work together to significantly improve the viscosity and adhesion of the hot melt adhesive, so that it can adhere more firmly to various substrates. It can improve the wettability of the hot melt adhesive at the bonding interface, so that the hot melt adhesive can better penetrate into the tiny pores of the substrate to form a stronger bonding force. The heat resistance of the hot melt adhesive can be enhanced, so that it can still maintain a stable bonding effect under high temperature conditions. The melt viscosity of the hot melt adhesive can be adjusted to improve fluidity, making it more suitable for different processing equipment and process requirements.

[0085] In some possible implementations, the raw material components of the reactive hot melt adhesive include 30 to 45 parts of solid tackifying resin and 5 to 15 parts of liquid tackifying resin. In this case, adding solid tackifying resin to the reactive hot melt adhesive can improve the initial cohesive strength of the hot melt adhesive and shorten the surface drying time, thereby adjusting the initial adhesion strength and rapid bonding and positioning ability of the hot melt adhesive. At the same time, solid tackifying resins with different softening points allow the hot melt adhesive to have corresponding heat resistance; excessive use will reduce the adhesive strength and low temperature resistance of the glue. At the same time, due to the low glass transition temperature Tg of the liquid tackifying resin added, the appropriate amount of liquid tackifying resin can significantly increase the viscosity of the hot melt adhesive, improve elasticity and low temperature resistance, and obtain certain pressure-sensitive properties.

[0086] In some embodiments, among the raw material components of the reactive hot melt adhesive, the weight proportion of the solid tackifying resin can be 30 parts, 33 parts, 35 parts, 38 parts, 40 parts, 42 parts, 45 parts, etc. and the weight proportion of the liquid tackifying resin can be 5 parts, 8 parts, 10 parts, 12 parts, 15 parts, etc.

[0087] In some possible implementations, the softening point of the solid tackifying resin is 80°C to 130°C; exemplary examples may be 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, etc. In this case, the solid tackifying resin has better processing properties, thereby ensuring that the hot melt adhesive has better application performance. When the softening point of the solid tackifying resin is low, the initial bonding strength of the hot melt adhesive will be weakened, and the heat resistance of the hot melt adhesive colloid after full curing will be reduced; when the softening point is too high, on the one hand, it will reduce the compatibility of the system and affect the bonding strength of the hot melt adhesive. On the other hand, at the same melting temperature, the viscosity of the tackifying resin glue with a higher softening point is also higher, which is not conducive to the application of the hot melt adhesive.

[0088] In some possible implementations, the solid tackifying resin is selected from at least one of aliphatic resin (C5), alicyclic resin (DCPD), aromatic resin (C9), aliphatic / aromatic copolymer resin (C5 / C9), aliphatic / aromatic copolymer resin (C5 / C9), C5 hydrogenated petroleum resin, and C9 hydrogenated petroleum resin. These solid tackifying resins can significantly increase the interaction force between molecules, improve the bonding strength of the hot melt adhesive, and enable the hot melt adhesive to better adhere to the substrate. The addition of solid tackifying resin can improve the heat resistance of the hot melt adhesive, so that the hot melt adhesive can still maintain a stable bonding effect under high temperature conditions. It can also reduce the melt viscosity of the hot melt adhesive, which helps the hot melt adhesive to better wet the surface of the adherend in a molten state, thereby improving the bonding quality. The solid tackifying resin can also increase the cohesive force of the hot melt adhesive, so that the hot melt adhesive forms a more solid bonding layer after curing.

[0089] In some preferred embodiments, the solid tackifying resin is selected from at least one of an aliphatic resin (C5), an aromatic resin (C9), and an aliphatic / aromatic copolymer resin (C5 / C9).

[0090] In some possible implementations, the liquid tackifying resin is liquid at room temperature. In some possible implementations, the liquid tackifying resin is selected from at least one of aliphatic resin (C5), liquid rosin tackifying resin, liquid monomer tackifying resin aromatic resin (AMS), and liquid aromatic resin (C9). These liquid tackifying resins can infiltrate the surface of the adherend more quickly due to their good fluidity, thereby improving the bonding efficiency. In addition, the addition of liquid tackifying resins may help to improve the initial viscosity of the hot melt adhesive, so that the hot melt adhesive can produce a stronger bonding effect in the early stage of curing. Since the liquid tackifying resin can be more easily mixed with other components, the formula of the hot melt adhesive can be adjusted more flexibly to meet different application requirements.

[0091] In some possible implementations, the antioxidant is selected from at least one of antioxidant 245, antioxidant 1010, antioxidant 1076, antioxidant 1098 and antioxidant 1024. In a high temperature environment, hot melt adhesive is prone to oxidation reaction, resulting in adverse effects such as decreased viscosity and reduced viscosity, and then losing the adhesive function. Adding an appropriate amount of antioxidant can eliminate or reduce the occurrence of oxidation reaction and maintain the normal performance of the hot melt adhesive. It can effectively extend the service life of the hot melt adhesive and slow down its aging rate. In addition, the antioxidant can maintain the stability and adhesion performance of the hot melt adhesive.

[0092] In some preferred embodiments, the antioxidant is selected from at least one of antioxidant 1010 and antioxidant 1076.

[0093] In some possible implementations, the catalyst is selected from at least one of dibutyltin dilaurate, stannous octoate, tetramethylethylenediamine, triethylenediamine, bismorpholinyl diethyl ether and dimorpholine triethyl ether. In some preferred embodiments, the catalyst is bismorpholinyl diethyl ether. Adding an appropriate amount of catalyst to the hot melt adhesive can accelerate its curing speed and improve application efficiency.

[0094] In some possible implementations, the defoamer is a non-silicone polymer defoamer. In some specific embodiments, the defoamer is BYK-A535. Hot melt adhesive may generate bubbles or foam during the manufacturing and application process, which will reduce the adhesion and bonding strength of the glue. The main function of the defoamer is to inhibit the formation of foam and ensure that the glue does not generate too much foam when it is used. The defoamer can also improve the fluidity of the hot melt adhesive, making it easier to apply or spray during the application process. By reducing the viscosity and surface tension of the glue, the defoamer helps to evenly apply the glue, providing better coverage and bonding effect. In addition, the defoamer also has the function of improving the transparency of the glue, which can reduce bubbles and foam in the glue and provide a clear and transparent bonding effect. At the same time, by eliminating foam and improving the wettability of the glue, the defoamer can improve the bonding strength and better penetrate and bond the glue to different material surfaces.

[0095] In some possible implementations, the stabilizer is selected from at least one of phosphoric acid, benzoyl chloride, benzoic acid and polyphosphoric acid. In some embodiments, the stabilizer is selected from at least one of phosphoric acid and polyphosphoric acid. Adding an appropriate amount of stabilizer to the adhesive can significantly improve its heat aging resistance and prevent the adhesive from softening, flowing or even failing in a high temperature environment. The stabilizer can also help the adhesive maintain good bonding strength and durability, ensuring excellent bonding effects in various harsh environments.

[0096] The reactive hot melt adhesive of the above embodiment of the present application can be prepared by the following embodiment method.

[0097] In a second aspect, the present application provides a method for preparing a reactive hot melt adhesive, as shown in the attached Figure 1 As shown, the following steps are included:

[0098] S10. In a dry inert atmosphere, 15 to 30 parts of dimer acid-modified polyester polyol, 5 to 15 parts of isocyanate, 10 to 20 parts of thermoplastic elastomer, 35 to 60 parts of tackifying resin, 0.05 to 0.5 parts of antioxidant, 0.05 to 0.3 parts of defoaming agent, 0.01 to 0.1 parts of stabilizer and 0.01 to 0.3 parts of catalyst are mixed to obtain a reactive hot melt adhesive.

[0099] The method for preparing the reactive hot melt adhesive in the embodiment of the present application is carried out in a dry inert atmosphere to prevent water, oxygen and other substances in the environment from affecting the raw material components and the stability of the hot melt adhesive. The reactive hot melt adhesive can be prepared by mixing the raw material components in the formula. The preparation process is simple and suitable for industrial large-scale production and application. The prepared reactive hot melt adhesive has excellent initial bonding strength, good bonding compatibility with low-polarity and high-polarity substrates, excellent thermal stability, and excellent resistance to high temperature and high humidity after curing.

[0100] In some possible implementations, the inert atmosphere includes at least one of nitrogen, argon, and helium.

[0101] In some possible implementations, the mixing process includes:

[0102] S11. The tackifying resin, thermoplastic elastomer, antioxidant, defoamer and stabilizer are first mixed and melted to obtain a first mixture. The components such as the tackifying resin and thermoplastic elastomer with a higher melting point are first melt-mixed, and additives such as antioxidant, defoamer and stabilizer are added at the same time to improve the stability of the molten mixture.

[0103] In some possible implementations, the temperature condition of the first mixed melting is 120° C. to 200° C., and examples thereof may be 120° C., 130° C., 140° C., 150° C., 160° C., 170° C., 180° C., 190° C., 200° C., etc. Under this condition, sufficient stirring is performed to ensure that the components such as the tackifying resin, the thermoplastic elastomer, the antioxidant, the defoaming agent, and the stabilizer are completely melted and mixed to form the first mixture.

[0104] S12. The first mixture and the dimer acid-modified polyester polyol are subjected to a second mixed melting process to obtain a second mixture. In this case, the first mixture and the dimer acid-modified polyester polyol are fully melt-mixed by the second mixed melting process to obtain the second mixture.

[0105] In some possible implementations, the temperature condition of the second mixed melting is 100° C. to 130° C., and exemplary temperatures may be 100° C., 110° C., 120° C., 130° C., etc. Under this temperature condition, it can be fully ensured that the first mixture and the dimer acid-modified polyester polyol are melt-mixed.

[0106] In some possible implementations, after obtaining the second mixture, evacuate to a vacuum degree of -0.05MPa to 0.095MPa, and dry and dehydrate to make the moisture content in the second mixture less than 0.05wt%. In this case, it is beneficial to improve the stability of subsequent mixing. If dehydration is insufficient, the residual moisture will react with isocyanate to generate allophanate, resulting in excessive viscosity of the hot melt adhesive or even gel. In addition, the temperature resistance of allophanate is not as good as that of urethane.

[0107] S13. After the second mixture is mixed with isocyanate for reaction, a catalyst is added, and after degassing treatment, a reactive hot melt adhesive is obtained. In this case, the isocyanate reacts with the dimer acid-modified polyester polyol to generate an NCO-terminated prepolymer, and the NCO group can react with moisture in the environment to generate an allophanate, so that the prepolymer forms a cross-linked network structure, further improving the bonding strength and moisture and heat resistance of the hot melt adhesive.

[0108] In some possible implementations, the temperature condition of the mixing reaction is 95°C to 115°C, and the duration is 1.5h to 2h; in this case, it can fully ensure that the isocyanate reacts with the dimer acid-modified polyester polyol to generate an NCO-terminated prepolymer, so that the prepolymer forms a cross-linked network structure, further improving the bonding strength and moisture and heat resistance of the hot melt adhesive.

[0109] Exemplarily, the temperature conditions of the mixed reaction can be 95° C., 100° C., 105° C., 110° C., 115° C., etc., and the duration can be 1.5 h, 1.8 h, 2 h, etc.

[0110] In some possible implementations, the degassing treatment conditions include: heating to 160°C to 180°C and stirring to degas for 30min to 50min in an inert atmosphere with a vacuum degree of -0.05MPa to 0.095MPa. In this case, bubbles in the hot melt adhesive can be fully removed, further ensuring that the raw material components are fully mixed and uniform.

[0111] In some embodiments, a method for preparing a reactive hot melt adhesive comprises the following steps:

[0112] S21. In a dry nitrogen atmosphere, the solid tackifying resin, the liquid tackifying resin, the styrene block copolymer, the antioxidant, the defoaming agent and the stabilizer are heated to 120°C to 200°C, stirred and completely melted to obtain a first mixture;

[0113] S22. In a dry nitrogen atmosphere, the first mixture is cooled to 100 ℃ ~ 130 ℃, and then a dimer acid-modified polyester polyol is added to obtain a second mixture, which is evacuated to a vacuum degree of -0.05MPa ~ 0.095MPa, and dried and dehydrated until the moisture content of the second mixture is less than 0.05wt%;

[0114] S23. Under a dry nitrogen atmosphere, the second mixture was cooled to 95°C to 115°C, isocyanate was added, and the mixture was reacted at 95°C to 115°C for 1.5h to 2h, and then a catalyst was added and stirred to obtain a third mixture;

[0115] S24. Under the conditions of dry nitrogen protection atmosphere and vacuum degree of -0.05MPa to 0.095MPa, the third mixture is heated to 160°C to 180°C and stirred for degassing for 30min to 50min to obtain the desired high initial adhesion strength reactive hot melt adhesive.

[0116] The third aspect provides an application of the reactive hot melt adhesive of the first aspect of the embodiment of the present application and / or the reactive hot melt adhesive prepared by the preparation method of the second aspect in at least one field of packaging industry, shoe material and fabric, electronic and electrical manufacturing industry, automobile manufacturing industry, woodworking manufacturing industry, medical and health field, construction, new energy, machinery manufacturing, printing and binding, anti-static flocking, static electricity protection, daily maintenance, and handmade production.

[0117] The reactive hot melt adhesive provided in the above embodiments of the present application has excellent initial bonding strength, good bonding compatibility with low-polarity and high-polarity substrates, excellent thermal stability, and excellent resistance to high temperature and high humidity after curing. Therefore, it can be widely used in the packaging industry, shoe fabrics, electronic and electrical manufacturing, automobile manufacturing, woodworking manufacturing, medical and health fields, construction, new energy, machinery manufacturing, printing and binding, anti-static flocking, static protection, daily maintenance, hand-made and other fields.

[0118] In some embodiments, the reactive hot melt adhesive of the embodiment of the present application is applied to the packaging industry: hot melt adhesive plays an important role in the packaging industry and is widely used in the sealing of cartons, paper boxes, corrugated boxes and cardboard boxes, as well as the packaging sealing of food, beverages, cosmetics, medicines and other products.

[0119] In some embodiments, the reactive hot melt adhesive of the present application is applied to shoe fabrics: In the footwear and textile industries, hot melt adhesives are used in the production of shoes, hats, clothing, and other products. It can effectively bond different materials, such as leather, cloth, rubber, etc., to improve the comfort and durability of the product.

[0120] In some embodiments, the reactive hot melt adhesive of the present application is applied to the electronic and electrical manufacturing industry: hot melt adhesive is widely used in the electronic and electrical industry, such as for fixing household appliance parts, electronic product nameplates, LED advertising luminous characters, and packaging and insulation of circuit boards, wires, components, etc. Its high bonding strength and high and low temperature resistance make it an indispensable adhesive in electronic and electrical products.

[0121] In some embodiments, the reactive hot melt adhesive of the present application is applied to the automobile manufacturing industry: in automobile manufacturing, hot melt adhesive is used for bonding automobile interiors, such as automobile seats, carpets, sound insulation materials, etc. Its heat resistance, cold resistance and impact resistance ensure the stability and safety of automobile interiors.

[0122] In some embodiments, the reactive hot melt adhesive of the present application is applied to the woodworking industry: In the woodworking industry, hot melt adhesive is used for splicing and repairing wooden products such as furniture, doors and windows, and floors. Its fast curing, high strength, and easy operation make it an ideal adhesive in woodworking manufacturing.

[0123] In some embodiments, the reactive hot melt adhesive of the present application is applied to the medical and health field: Hot melt adhesive is also used in the medical and health field, such as for bonding and fixing medical dressings and surgical instruments. Its non-toxic, odorless and pollution-free properties ensure the safety and reliability of medical products.

[0124] In some embodiments, the reactive hot melt adhesive of the present application is applied to other fields: In addition to the above fields, hot melt adhesive is also widely used in construction, new energy, machinery manufacturing, printing and binding, anti-static flocking, static protection, daily maintenance, hand-made and other fields. For example, it is used for bonding of building materials, packaging of new energy equipment, assembly of mechanical equipment, etc.

[0125] In order to enable the above implementation details and operations of the present application to be clearly understood by those skilled in the art, as well as to demonstrate the significant improvement in the performance of the reactive hot melt adhesive and the preparation method thereof in the embodiments of the present application, the above technical solution is illustrated by means of multiple embodiments below.

[0126] Example 1

[0127] A reactive hot melt adhesive, the preparation of which comprises the following steps:

[0128] Solid tackifying resin P-90 22 parts, solid tackifying resin YL120 20 parts, liquid tackifying resin Picco A10 12.9 parts, styrene block copolymer SIS1105 14 parts, antioxidant 10100.30 parts, defoaming agent BYK-A535 0.10 parts and phosphoric acid 0.01 parts were added into a three-necked flask, heated to 190°C under dry nitrogen protection, stirred thoroughly and completely melted, cooled to 110°C, and dimer acid-modified polyester polyol Priplast 3192 was added. 23.29 parts (whose hydroxyl value is 56 mgKOH / g), dried and dehydrated at a vacuum degree of -0.05 to 0.095 MPa for 2 hours, and then cooled to 95°C; 7.30 parts of diphenylmethane 4,4'-diisocyanate (MDI) were continued to be added, and the mixture was reacted at 110°C for 1.5 hours under the protection of dry nitrogen, and then 0.10 parts of dimorpholinyl diethyl ether were added, and the mixture was heated to 170°C, and the bubbles were removed by stirring at a vacuum degree of -0.05 to 0.095 MPa for 30 minutes, and the mixture was discharged under the protection of dry nitrogen, and sealed to obtain a reactive hot melt adhesive with high initial adhesion strength.

[0129] Example 2

[0130] A reactive hot melt adhesive, the preparation of which comprises the following steps:

[0131] Solid tackifying resin P-90 22.66 parts, solid tackifying resin YL120 20 parts, liquid tackifying resin Picco A10 10 parts, styrene block copolymer SIS1105 14 parts, antioxidant 10100.30 parts, defoaming agent BYK A535 0.10 parts and phosphoric acid 0.01 parts were added into a three-necked flask, heated to 190°C under dry nitrogen protection, stirred thoroughly and completely melted, cooled to 110°C, and dimer acid-modified polyester polyol BY 3026 was added. 25 parts (whose hydroxyl value is 56 mgKOH / g), dried and dehydrated at a vacuum degree of 0.05-0.095 MPa for 2 hours, and then cooled to 95°C; 7.83 parts of diphenylmethane 4,4'-diisocyanate (MDI) were continued to be added, and the mixture was reacted at 110°C for 1.5 hours under the protection of dry nitrogen, and then 0.10 parts of dimorpholinyl diethyl ether were added, and the mixture was heated to 170°C, and the bubbles were removed by stirring at a vacuum degree of 0.05-0.095 MPa for 30 minutes, and the mixture was discharged under the protection of dry nitrogen, and sealed to obtain a reactive hot melt adhesive with high initial adhesion strength.

[0132] Example 3

[0133] A reactive hot melt adhesive, the preparation of which comprises the following steps:

[0134] Solid tackifying resin P-90 22 copies, 21 parts of P110S, 11 parts of liquid tackifying resin NOVARES TM-20AS, 14 parts of styrene block copolymer SIS1105, 0.30 parts of antioxidant 1010, 0.10 parts of defoaming agent BYK A535 and 0.01 parts of phosphoric acid were added into a three-necked flask, heated to 190°C under dry nitrogen protection, stirred thoroughly and completely melted, cooled to 110°C, and dimer acid-modified polyester polyol BY 3026 was added. 24 parts (whose hydroxyl value is 56 mgKOH / g), dried and dehydrated at a vacuum degree of 0.05-0.095 MPa for 2 hours, and then cooled to 95°C; 7.49 parts of diphenylmethane 4,4'-diisocyanate (MDI) were continued to be added, and the mixture was reacted at 110°C for 1.5 hours under the protection of dry nitrogen, and then 0.10 parts of dimorpholinyl diethyl ether were added, and the mixture was heated to 170°C, and the bubbles were removed by stirring at a vacuum degree of 0.05-0.095 MPa for 30 minutes, and the mixture was discharged under the protection of dry nitrogen, and sealed to obtain a reactive hot melt adhesive with high initial adhesion strength.

[0135] Example 4

[0136] A reactive hot melt adhesive, the preparation of which comprises the following steps:

[0137] A reactive hot melt adhesive, the preparation of which comprises the following steps:

[0138] Solid tackifying resin 32 parts of P-90, 12 parts of YL120, 11.1 parts of liquid tackifying resin Picc A10, 14 parts of styrene block copolymer SEBS 6951, 0.30 parts of antioxidant 1010, 0.10 parts of defoamer BYK A535 and 0.01 parts of phosphoric acid were added into a three-necked flask, heated to 190°C under dry nitrogen protection, stirred thoroughly and completely melted, cooled to 110°C, and dimer acid-modified polyester polyol Priplast 3192 was added. 23.09 parts (whose hydroxyl value is 56mgmgKOH / g), dried and dehydrated at a vacuum degree of 0.05-0.095MPa for 2h, and then cooled to 95°C; 7.3 parts of diphenylmethane 4,4'-diisocyanate (MDI) were continued to be added, and the mixture was reacted at 110°C for 1.5h under the protection of dry nitrogen, and then 0.10 parts of dimorpholino diethyl ether were added, and the mixture was heated to 170°C, and the bubbles were removed by stirring at a vacuum degree of 0.05-0.095MPa for 30 minutes, and the mixture was discharged under the protection of dry nitrogen, and sealed to obtain a reactive hot melt adhesive with high initial adhesion strength.

[0139] Comparative Example 1

[0140] A reactive hot melt adhesive, the preparation of which comprises the following steps:

[0141] A reactive hot melt adhesive, the preparation of which comprises the following steps:

[0142] Solid tackifying resin P-90 22 parts, YL120 20 parts, liquid tackifying resin Picc A10 12.9 parts, styrene block copolymer SIS1105 14 parts, antioxidant 1010 0.30 parts, defoamer BYK A535 0.10 parts and phosphoric acid 0.01 parts were added into a three-necked flask, heated to 190°C under dry nitrogen protection, stirred thoroughly and completely melted, cooled to 110°C, polyester polyol Stepanpol 23.29 parts of PS-2002 (whose hydroxyl value is 56mgmgKOH / g) were dried and dehydrated at a vacuum degree of 0.05-0.095MPa for 2h, and then cooled to 95°C; 7.3 parts of diphenylmethane 4,4'-diisocyanate (MDI) were added, and the mixture was reacted at 110°C for 1.5h under the protection of dry nitrogen, and then 0.10 parts of dimorpholino diethyl ether were added, and the mixture was heated to 170°C. The mixture was stirred to remove bubbles at a vacuum degree of 0.05-0.095MPa for 30 minutes, and the mixture was discharged under the protection of dry nitrogen, and sealed to obtain a reactive hot melt adhesive.

[0143] Comparative Example 2

[0144] A reactive hot melt adhesive, the preparation of which comprises the following steps:

[0145] Solid tackifying resin P-90 22 parts, YL120 20 parts, liquid tackifying resin Picc A10 12.9 parts, amorphous α-olefin copolymer VESTOPLAST 308 14 parts, antioxidant 1010 0.30 parts, defoamer BYK A535 0.10 parts and phosphoric acid 0.01 parts were added into a three-necked flask, heated to 190°C under dry nitrogen protection, stirred thoroughly and completely melted, cooled to 110°C, and dimer acid-modified polyester polyol Priplast 3192 was added. 23.29 parts (whose hydroxyl value is 56mgmgKOH / g), dried and dehydrated at a vacuum degree of 0.05-0.095MPa for 2h, and then cooled to 95°C; 7.3 parts of diphenylmethane 4,4'-diisocyanate (MDI) were continued to be added, and the mixture was reacted at 110°C for 1.5h under the protection of dry nitrogen, and then 0.10 parts of dimorpholino diethyl ether were added, and the mixture was heated to 170°C, and the bubbles were removed by stirring at a vacuum degree of 0.05-0.095MPa for 30 minutes, and the mixture was discharged under the protection of dry nitrogen, and sealed to obtain a reactive hot melt adhesive.

[0146] Comparative Example 3

[0147] A reactive hot melt adhesive, the preparation of which comprises the following steps:

[0148] Solid tackifying resin 8.61 parts of P-90, 19.91 parts of YL120, 6.35 parts of liquid tackifying resin Picc A10, 15.07 parts of styrene block copolymer SEBS 6951, 0.32 parts of antioxidant 1010, 0.11 parts of defoamer BYKA535 and 0.01 parts of phosphoric acid were added into a three-necked flask, heated to 190°C under dry nitrogen protection, stirred thoroughly and completely melted, cooled to 110°C, and dimer acid-modified polyester polyol Priplast 3192 was added. 37.67 parts (whose hydroxyl value is 56mgmgKOH / g), dried and dehydrated at a vacuum degree of 0.05-0.095MPa for 2h, and then cooled to 95°C; 11.84 parts of diphenylmethane 4,4'-diisocyanate (MDI) were continued to be added, and the mixture was reacted at 110°C for 1.5h under the protection of dry nitrogen, and then 0.11 parts of dimorpholino diethyl ether were added, and the mixture was heated to 170°C, and the bubbles were removed by stirring at a vacuum degree of 0.05-0.095MPa for 30 minutes, and the mixture was discharged under the protection of dry nitrogen, and sealed to obtain a highly reactive hot melt adhesive.

[0149] In order to verify the progress of the embodiments of the present application, the following performance tests were performed on the above embodiments:

[0150] 1. Viscosity test: Use Shanghai Jingtian LVDV-1 rotational viscometer at 170℃, 27# rotor.

[0151] 2. Open time test: The hot melt adhesive prepared in the embodiment of the present application was melted at 170° C. for 30 min, and a glue line was drawn on a smooth flat plate using a 20# needle, and the time when the adhesive layer surface was sticky was recorded.

[0152] 3. Initial adhesive peel strength test: Use a 20# needle to adjust the amount of hot melt glue to 0.4mg / mm, and stick another PET film after dotting the glue line on the PET film. The sample is made by hot pressing for 3s at 130℃ and 0.3Mpa. After standing for 2 minutes, it is cut into 8mm wide strips. The T-type peel strength of the 25℃ strips is tested at a speed of 100mm / min using a desktop testing machine. The maximum peel force of each strip is recorded. 10 strips are tested for each sample and the average value is calculated.

[0153] 4. Final peel strength test: Use a 20# needle to adjust the amount of hot melt glue to 0.4mg / mm, and stick another PET film after dotting the glue line on the PET film. The sample is made by hot pressing at 130℃, 0.3Mpa for 3s. After hot pressing, the sample is placed at 25℃, 60% RH for 48H and then cut into 8mm wide strips. Then, a desktop testing machine is used to test the T-type peel strength of the 25℃ strips at a speed of 100mm / min. The maximum peel force of each strip is recorded. Ten strips are tested for each sample and the average value is calculated.

[0154] 5. High temperature and high humidity resistance test: The adhesive sample prepared in the embodiment of the present application was cured at 25°C and 60% humidity for 48 hours, then cut into 8 mm wide strips, placed at 85°C and 85% RH for 100 hours, and then the T-peel strength of the 25°C strips was tested using a desktop testing machine with a peeling speed of 100 mm / min. The maximum peeling force of each strip was recorded, 10 strips were tested for each sample, and the average value was calculated.

[0155] 6. Thermal stability test: The glue is sealed and placed in 170℃ for continuous heating and aging for 48 hours. Then the viscosity of the glue is tested and the growth rate of the thermal aging viscosity is calculated:

[0156] Heat aging viscosity growth rate = ((viscosity after heat aging - viscosity before aging) / viscosity before aging) * 100%.

[0157] The above test results are shown in Table 1 below:

[0158] Table 1

[0159]

[0160]

[0161] From the test results in Table 1 above, it can be seen that the reactive hot melt adhesive with high initial adhesive strength prepared in Examples 1 to 4 has very high initial adhesive strength after dispensing, is very stable under high temperature conditions, and the viscosity of the glue remains stable after long-term high-temperature heating. The peel strength does not decrease significantly after the double 85 test, and has good high temperature and high humidity resistance. However, when the unmodified polyester polyol is used in Comparative Example 1, the styrene block copolymer in Comparative Example 2 is replaced with an amorphous α-olefin copolymer, and the component content in the hot melt adhesive in Comparative Example 3 is too high or too low, the initial adhesive strength, adhesive compatibility, thermal stability and other properties of the hot melt adhesive will be significantly reduced.

[0162] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A reactive hot melt adhesive, characterized in that: Calculated by mass, it includes the following raw material components: 15 to 30 parts of dimer acid modified polyester polyol, 5 to 15 parts of isocyanate, Thermoplastic elastomer 10 to 20 parts, 35 to 60 parts of tackifying resin, 0.05 to 0.5 parts of antioxidant, Defoaming agent 0.05 to 0.3 parts, Stabilizer 0.01 to 0.1 parts, Catalyst 0.01 to 0.3 parts.

2. The reactive hot melt adhesive according to claim 1, characterized in that: The hydroxyl value of the dimer acid-modified polyester polyol is 35 mgKOH / g to 80 mgKOH / g; And / or, the dimer acid-modified polyester polyol comprises a main chain and at least two side chains, wherein the main chain has 30 to 50 carbon atoms, and a single side chain has 8 to 15 carbon atoms; And / or, in the reactive hot melt adhesive, the content of isocyanate groups is 1wt% to 2.5wt%; and / or, the thermoplastic elastomer comprises a styrene block copolymer; And / or, the tackifying resin includes a solid tackifying resin and a liquid tackifying resin.

3. The reactive hot melt adhesive according to claim 2, characterized in that: The dimer acid-modified polyester polyol is selected from at least one of Priplast 3192, Priplast 3190, DA-2110, DA-21, BY 3026, and BY 3022; The raw material components of the reactive hot melt adhesive include 30 to 45 parts of the solid tackifying resin and 5 to 15 parts of the liquid tackifying resin; and / or, the softening point of the solid tackifying resin is 80° C. to 130° C.; And / or, the liquid tackifying resin is liquid at room temperature.

4. The reactive hot melt adhesive according to claim 2 or 3, characterized in that: The isocyanate is selected from at least one of toluene diisocyanate isomers, diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, carbodiimide-modified diphenylmethane-4,4'-diisocyanate, naphthalene-1,4-diisocyanate, xylylene diisocyanate, and 1,4-phenylene diisocyanate; And / or, the styrene block copolymer is selected from at least one of ethylene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-ethylene-butylene-styrene, and styrene-ethylene-propylene-styrene; and / or, the liquid tackifying resin is selected from at least one of aliphatic resin, liquid rosin tackifying resin, liquid monomer tackifying resin aromatic resin, and liquid aromatic resin; And / or, the solid tackifying resin is at least one selected from aliphatic resins, alicyclic resins, aromatic resins, aliphatic / aromatic copolymer resins, C5 hydrogenated petroleum resins, and C9 hydrogenated petroleum resins.

5. The reactive hot melt adhesive according to claim 1, characterized in that: The antioxidant is selected from at least one of antioxidant 245, antioxidant 1010, antioxidant 1076, antioxidant 1098 and antioxidant 1024; And / or, the catalyst is selected from at least one of dibutyltin dilaurate, stannous octoate, tetramethylethylenediamine, triethylenediamine, bismorpholinyl diethyl ether and dimorpholine triethyl ether; and / or, the defoamer is a non-silicone polymer defoamer; And / or, the stabilizer is selected from at least one of phosphoric acid, benzoyl chloride, benzoic acid and polyphosphoric acid.

6. A method for preparing a reactive hot melt adhesive, characterized in that: The following steps are involved: In a dry inert atmosphere, 15 to 30 parts of dimer acid-modified polyester polyol, 5 to 15 parts of isocyanate, 10 to 20 parts of thermoplastic elastomer, 35 to 60 parts of tackifying resin, 0.05 to 0.5 parts of antioxidant, 0.05 to 0.3 parts of defoaming agent, 0.01 to 0.1 parts of stabilizer and 0.01 to 0.3 parts of catalyst are mixed to prepare a reactive hot melt adhesive.

7. The method for preparing a reactive hot melt adhesive according to claim 6, characterized in that: The inert atmosphere includes at least one of nitrogen, argon and helium; And / or, the mixing step includes: The tackifying resin, the thermoplastic elastomer, the antioxidant, the defoaming agent and the stabilizer are first mixed and melted to obtain a first mixture; Performing a second mixing and melting of the first mixture and the dimer acid-modified polyester polyol to obtain a second mixture; After the second mixture and the isocyanate are mixed and reacted, the catalyst is added, and the reaction-type hot melt adhesive is obtained after degassing treatment.

8. The method for preparing a reactive hot melt adhesive according to claim 7, characterized in that: The temperature condition of the first mixed melting is 120°C to 200°C; And / or, the temperature condition of the second mixed melting is 100° C. to 130° C.; And / or, the moisture content in the second mixture is lower than 0.05 wt %.

9. The method for preparing a reactive hot melt adhesive according to claim 8, characterized in that: The temperature condition of the mixed reaction is 95°C to 115°C, and the duration is 1.5h to 2h; And / or, the degassing treatment conditions include: in an inert atmosphere with a vacuum degree of -0.05 MPa to 0.095 MPa, heating to 160° C. to 180° C. and stirring for degassing for 30 min to 50 min.

10. Application of the reactive hot melt adhesive according to any one of claims 1 to 5 and / or the reactive hot melt adhesive prepared by the preparation method according to any one of claims 6 to 9 in at least one of the following fields: packaging industry, shoe fabrics, electronic and electrical manufacturing, automobile manufacturing, woodworking manufacturing, medical and health fields, construction, new energy, machinery manufacturing, printing and binding, antistatic flocking, electrostatic protection, daily maintenance, and handmade production.

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