Hot-melt pressure-sensitive adhesive and production process thereof
By adding organic montmorillonite, crosslinking components and initiators to the SIS hot melt pressure sensitive adhesive, the crosslinking reaction and the introduction of polar functional groups are achieved, which solves the problem of insufficient anti-aging ability of SIS hot melt pressure sensitive adhesive, and significantly improves its heat, water and bonding properties.
Patent Information
- Application Number
- CN202411763464.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-03
- Publication Date
- 2025-03-28
AI Technical Summary
The existing SIS hot melt pressure sensitive adhesives have insufficient anti-aging ability, especially under the oxidation conditions of high-temperature air, the blocks will be cross-linked or degraded, resulting in a degradation of bonding performance.
Organic montmorillonite, crosslinking components and initiators are added to SIS hot melt pressure-sensitive adhesive, which consumes unsaturated double bonds on the SIS molecular chain through the crosslinking reaction to improve the antioxidant performance, and improves heat resistance, water resistance and bonding performance by introducing polar functional groups and inorganic clay.
It significantly improves the antioxidant, heat resistance, water resistance and bonding properties of hot melt pressure-sensitive adhesive, and enhances its stability in high temperature and moisture environments.
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Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of pressure-sensitive adhesives, and in particular relates to a hot-melt pressure-sensitive adhesive and a production process thereof. Background Art
[0002] Hot melt pressure sensitive adhesive is a type of environmentally friendly adhesive that does not contain water or solvents. It has obvious and lasting initial adhesion at room temperature. At the same time, it can be firmly bonded to various surfaces within a few seconds with just a slight pressure (1-10Pa). Because it does not contain organic solvents, it is recognized as an environmentally friendly pressure sensitive adhesive. Its main components are polymer matrix (mostly thermoplastic elastomers), tackifier resin, plasticizer and filler.
[0003] Thermoplastic elastomer is a polymer material that has the properties of vulcanized rubber at room temperature and thermoplastic plasticity at high temperatures after heating. Compared with other types of styrene thermoplastic elastomers, the hot melt properties of styrene-isoprene block copolymer (SIS) show lower melt viscosity and excellent bonding properties, which makes it widely used in the research of hot melt pressure-sensitive adhesives.
[0004] SIS hot melt pressure sensitive adhesive has good cohesion, low melt viscosity, high adhesion, and relatively complete production technology. It is often used as adhesive for waterproof membranes. However, due to the small polarity of SIS molecules and the presence of unsaturated bonds, the performance of SIS hot melt pressure sensitive adhesive products is limited, especially the lack of anti-aging ability. Under the oxidative conditions of high temperature air, SIS blocks will crosslink or degrade, thereby reducing the bonding performance and seriously affecting the comprehensive performance of waterproof membranes. Summary of the invention
[0005] The purpose of the present invention is to provide a hot melt pressure sensitive adhesive and a production process thereof, so as to solve the problem that the existing SIS hot melt pressure sensitive adhesive has insufficient anti-aging ability.
[0006] The purpose of the present invention can be achieved through the following technical solutions:
[0007] A hot melt pressure-sensitive adhesive comprises the following raw materials in parts by weight:
[0008] SIS thermoplastic elastomer 30 parts, plasticizer 15-17 parts, tackifying resin 53-55 parts, organic montmorillonite 1-2 parts, cross-linking component 0.5-3 parts, initiator 0.05-0.3 parts.
[0009] The organic montmorillonite is montmorillonite modified by a quaternary ammonium salt cationic intercalation agent.
[0010] The cross-linking component is itaconic acid hyperbranched polyester.
[0011] Further, the organized montmorillonite is prepared by the following steps:
[0012] Sodium montmorillonite is added into deionized water, stirred at room temperature for 30 minutes, aged for 24 hours, heated to 70-80°C, and an aqueous solution of a quaternary ammonium salt cationic intercalant is added dropwise, stirred for 3-5 hours at this temperature, centrifuged, and the precipitate is washed with deionized water, dried at 60°C, ground and sieved to obtain an organic montmorillonite.
[0013] Furthermore, the dosage ratio of montmorillonite, deionized water and aqueous solution of quaternary ammonium salt cationic intercalant is 20g:200mL:50-60g, and the mass fraction of quaternary ammonium salt cationic intercalant in the aqueous solution of quaternary ammonium salt cationic intercalant is 20-30%.
[0014] Further, the quaternary ammonium salt cationic intercalant is prepared by the following steps:
[0015] Add caffeic acid and p-toluenesulfonic acid into a flask containing DMF, stir evenly, then add DMF solution of terminal hydroxyl alkyl long-chain quaternary ammonium salt, stir and react at 90°C for 6-8h, then remove DMF by rotary evaporation to obtain a quaternary ammonium salt cationic intercalant.
[0016] Furthermore, the molar ratio of caffeic acid to terminal hydroxyl alkyl long-chain quaternary ammonium salt is 2:1, the amount of p-toluenesulfonic acid used is 0.2-0.4% of the mass of caffeic acid, and p-toluenesulfonic acid is used as a catalyst to cause caffeic acid and terminal hydroxyl alkyl long-chain quaternary ammonium salt to undergo esterification reaction to obtain a quaternary ammonium salt cationic intercalation agent.
[0017] Furthermore, the terminal hydroxyl alkyl long-chain quaternary ammonium salt is at least one of dodecylmethyldihydroxyethylammonium bromide, tetradecylmethyldihydroxyethylammonium bromide, hexadecylmethyldihydroxyethylammonium bromide, di(hydroxyethyl)methyldodecylammonium chloride, octadecylmethyldihydroxyethylammonium bromide and octadecylbishydroxyethylmethylammonium chloride.
[0018] Furthermore, the preparation method of the cross-linking component comprises the following steps:
[0019] Itaconic acid, trimethylolpropane, 1,4-dioxane and p-toluenesulfonic acid are added into a flask, the temperature is raised to 90-100°C, the reaction is stirred for 8 hours, and then 1,4-dioxane is removed by reduced pressure distillation to obtain a cross-linking component; the molar ratio of itaconic acid to trimethylolpropane is 3.5-4.0:2, the amount of 1,4-dioxane is 8-10 times the mass sum of itaconic acid and trimethylolpropane, and the amount of p-toluenesulfonic acid is 0.5-1% of the mass sum of itaconic acid and trimethylolpropane.
[0020] Furthermore, the SIS thermoplastic elastomer is SIS-1716 produced by Sinopec Baling Petrochemical Co., Ltd.
[0021] Furthermore, the plasticizer is at least one of liquid paraffin, naphthenic oil KN-4010 and liquid polyisobutylene PB-950.
[0022] Furthermore, the tackifying resin is at least one of hydrogenated terpene, C5 petroleum resin and hydrogenated C5 petroleum resin.
[0023] Furthermore, the initiator is at least one of benzoyl peroxide, potassium persulfate and azobisisobutyronitrile.
[0024] The production process of the hot melt pressure sensitive adhesive comprises the following steps:
[0025] Weigh the materials according to the formula, add SIS thermoplastic elastomer and plasticizer into a vacuum reactor, raise the temperature to 145-155°C under nitrogen protection, stir at 500-1000r / min for 30min, add organic montmorillonite, cross-linking component and initiator, continue stirring for 30-60min, finally add tackifying resin, raise the temperature to 150-160°C, stir for 40-60min, discharge while hot, and treat at a constant temperature of 25°C for 24h to obtain a hot melt pressure-sensitive adhesive.
[0026] Beneficial effects of the present invention:
[0027] 1. The present invention provides a hot melt pressure sensitive adhesive. An initiator, a crosslinking component and an organized montmorillonite are added to the SIS pressure sensitive adhesive system. A crosslinking reaction occurs between the three, and the unsaturated double bonds on the SIS thermoplastic elastomer molecular chain are consumed endogenously to improve its antioxidant performance. Polar functional groups and inorganic clay are introduced to improve the heat resistance, water resistance and bonding performance of the pressure sensitive adhesive.
[0028] 2. The organized montmorillonite provided by the present invention is a quaternary ammonium salt cationic intercalant modified montmorillonite, which has a large interlayer spacing, high compatibility with the pressure-sensitive adhesive matrix, and improves the heat resistance of the pressure-sensitive adhesive. It can also form a "zigzag effect" in the pressure-sensitive adhesive system to hinder the invasion of water molecules and improve the water resistance of the pressure-sensitive adhesive. In addition, the quaternary ammonium salt cationic intercalant also contains a long alkyl chain and a catechol structure. The good hydrophobicity of the long alkyl chain further enhances the water resistance of the pressure-sensitive adhesive, and the catechol structure significantly improves the bonding performance of the pressure-sensitive adhesive.
[0029] 3. The cross-linking component provided by the present invention is itaconic acid hyperbranched polyester, which is a highly branched three-dimensional macromolecule with abundant unsaturated double bonds. It can react with SIS thermoplastic elastomer and organic montmorillonite, thereby enhancing the cohesion and adhesion of the pressure-sensitive adhesive, and helping to improve the adhesion of the pressure-sensitive adhesive. In addition, the itaconic acid hyperbranched polyester also contains abundant carboxyl groups, which can improve the polarity of the product and further improve the adhesion. DETAILED DESCRIPTION
[0030] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0031] In the present application, the cation exchange capacity of sodium montmorillonite is 90 mmol / 100 g, which was purchased from Zhejiang Fenghong Co., Ltd., and the SIS thermoplastic elastomer is SIS-1716 from Sinopec Baling Petrochemical Co., Ltd.
[0032] Preparation Example 1
[0033] The preparation of the quaternary ammonium salt cationic intercalation agent comprises the following steps:
[0034] 0.2 mol of caffeic acid and 0.72 g of p-toluenesulfonic acid were added to a flask containing 200 mL of DMF, and after stirring evenly, 400 mL of a DMF solution containing 0.1 mol of dodecylmethyldihydroxyethylammonium bromide was added, and the mixture was stirred at 90° C. for 6 h, and DMF was removed by rotary evaporation to obtain a quaternary ammonium salt cationic intercalant.
[0035] Preparation Example 2
[0036] The preparation of the quaternary ammonium salt cationic intercalation agent comprises the following steps:
[0037] 0.2 mol of caffeic acid and 1.44 g of p-toluenesulfonic acid were added to a flask containing 200 mL of DMF, and after stirring evenly, 400 mL of a DMF solution containing 0.1 mol of tetradecylmethyl dihydroxyethyl ammonium bromide was added, and the mixture was stirred at 90° C. for 8 h, and DMF was removed by rotary evaporation to obtain a quaternary ammonium salt cationic intercalant.
[0038] Comparative Example 1
[0039] This comparative example is dodecylmethyldihydroxyethylammonium bromide.
[0040] Example 1
[0041] A hot melt pressure-sensitive adhesive comprises the following raw materials in parts by weight:
[0042] SIS thermoplastic elastomer 30 parts, naphthenic oil KN-4010 15 parts, C5 petroleum resin 53 parts, organic montmorillonite 1 part, cross-linking component 0.5 parts, benzoyl peroxide 0.05 parts.
[0043] The preparation steps of organic montmorillonite are as follows:
[0044] 20 g of sodium montmorillonite was added to 200 mL of deionized water, stirred at room temperature for 30 min, aged for 24 h, heated to 70° C., and 50 g of an aqueous solution of a quaternary ammonium salt cationic intercalant was added dropwise, wherein the mass fraction of the quaternary ammonium salt cationic intercalant in the aqueous solution of the quaternary ammonium salt cationic intercalant was 20%. The mixture was stirred at this temperature for 3 h, centrifuged, and the precipitate was washed with deionized water, dried at 60° C., ground and sieved to obtain an organic montmorillonite.
[0045] The preparation method of the cross-linking component comprises the following steps:
[0046] 3.5 mol of itaconic acid, 2 mol of trimethylolpropane, 5.8 L of 1,4-dioxane and 3.61 g of p-toluenesulfonic acid were added into a flask, the temperature was raised to 90° C., the reaction was stirred for 8 h, and then 1,4-dioxane was removed by reduced pressure distillation to obtain a cross-linking component.
[0047] The production process of the hot melt pressure sensitive adhesive comprises the following steps:
[0048] Weigh the materials according to the formula, add SIS thermoplastic elastomer and cyclohexane oil KN-4010 into a vacuum reactor, heat to 145°C under nitrogen protection, stir at 500r / min for 30min, add organic montmorillonite, cross-linking component and benzoyl peroxide, continue stirring for 30min, finally add C5 petroleum resin, heat to 150°C, stir for 40min, discharge while hot, and treat at a constant temperature of 25°C for 24h to obtain a hot melt pressure-sensitive adhesive.
[0049] Example 2
[0050] A hot melt pressure-sensitive adhesive comprises the following raw materials in parts by weight:
[0051] SIS thermoplastic elastomer 30 parts, liquid polyisobutylene PB-950 16 parts, hydrogenated C5 petroleum resin 54 parts, organic montmorillonite 1.5 parts, cross-linking component 2 parts, potassium persulfate 0.1 parts.
[0052] The preparation steps of organic montmorillonite are as follows:
[0053] 20 g of sodium montmorillonite was added to 200 mL of deionized water, stirred at room temperature for 30 min, aged for 24 h, heated to 75 ° C, and 55 g of an aqueous solution of a quaternary ammonium salt cationic intercalant was added dropwise, wherein the mass fraction of the quaternary ammonium salt cationic intercalant in the aqueous solution of the quaternary ammonium salt cationic intercalant of Preparation Example 2 was 25%. The mixture was stirred at this temperature for 4 h, centrifuged, and the precipitate was washed with deionized water, dried at 60 ° C, ground and sieved to obtain an organic montmorillonite.
[0054] The preparation method of the cross-linking component comprises the following steps:
[0055] 3.5 mol of itaconic acid, 2 mol of trimethylolpropane, 6.5 L of 1,4-dioxane and 5.88 g of p-toluenesulfonic acid were added into a flask, the temperature was raised to 98° C., the reaction was stirred for 8 h, and then 1,4-dioxane was removed by reduced pressure distillation to obtain a cross-linking component.
[0056] The production process of the hot melt pressure sensitive adhesive comprises the following steps:
[0057] Weigh the materials according to the formula, add SIS thermoplastic elastomer and liquid polyisobutylene PB-950 into a vacuum reactor, heat to 150°C under nitrogen protection, stir at 800rpm for 30min, add organic montmorillonite, cross-linking component and potassium persulfate, continue stirring for 40min, finally add hydrogenated C5 petroleum resin, heat to 155°C, stir for 50min, discharge while hot, and treat at a constant temperature of 25°C for 24h to obtain a hot melt pressure-sensitive adhesive.
[0058] Example 3
[0059] A hot melt pressure-sensitive adhesive comprises the following raw materials in parts by weight:
[0060] SIS thermoplastic elastomer 30 parts, naphthenic oil KN-4010 17 parts, C5 petroleum resin 55 parts, organic montmorillonite 2 parts, cross-linking component 3 parts, benzoyl peroxide 0.3 parts.
[0061] The preparation steps of organic montmorillonite are as follows:
[0062] 20 g of sodium montmorillonite was added to 200 mL of deionized water, stirred at room temperature for 30 min, aged for 24 h, heated to 80° C., and 60 g of an aqueous solution of a quaternary ammonium salt cationic intercalant was added dropwise, wherein the mass fraction of the quaternary ammonium salt cationic intercalant in the aqueous solution of the quaternary ammonium salt cationic intercalant of Preparation Example 2 was 30%. The mixture was stirred at this temperature for 5 h, centrifuged, and the precipitate was washed with deionized water, dried at 60° C., ground and sieved to obtain an organic montmorillonite.
[0063] The preparation method of the cross-linking component comprises the following steps:
[0064] 4.0 mol of itaconic acid, 2 mol of trimethylolpropane, 7.9 L of 1,4-dioxane and 7.88 g of p-toluenesulfonic acid were added into a flask, the temperature was raised to 100° C., the mixture was stirred for reaction for 8 h, and then 1,4-dioxane was removed by reduced pressure distillation to obtain a cross-linking component.
[0065] The production process of the hot melt pressure sensitive adhesive comprises the following steps:
[0066] Weigh the materials according to the formula, add SIS thermoplastic elastomer and cyclohexane oil KN-4010 into a vacuum reactor, heat to 155°C under nitrogen protection, stir at 1000r / min for 30min, add organic montmorillonite, cross-linking component and benzoyl peroxide, continue stirring for 60min, finally add C5 petroleum resin, heat to 160°C, stir for 60min, discharge while hot, and treat at a constant temperature of 25°C for 24h to obtain a hot melt pressure-sensitive adhesive.
[0067] Comparative Example 1
[0068] A hot melt pressure-sensitive adhesive, compared with Example 1, the quaternary ammonium salt cationic intercalant in Example 1 is replaced by the substance in Control Example 1, and the other raw materials, parameters and preparation process are the same as in Example 1.
[0069] Comparative Example 2
[0070] A hot melt pressure-sensitive adhesive, compared with Example 1, the itaconic acid in Example 1 is replaced by succinic acid, and the other raw materials, parameters and preparation process are the same as Example 1.
[0071] Comparative Example 3
[0072] A hot melt pressure-sensitive adhesive, compared with Example 1, the cross-linking component in Example 1 is replaced by pentaerythritol triacrylate, and the other raw materials, parameters and preparation process are the same as Example 1.
[0073] Comparative Example 4
[0074] A hot melt pressure-sensitive adhesive, compared with Example 1, the weight portion of the organized montmorillonite in Example 1 is adjusted to 0.5 parts, and the other raw materials, parameters and preparation process are the same as Example 1.
[0075] Comparative Example 5
[0076] A hot melt pressure-sensitive adhesive, compared with Example 3, the weight of the organized montmorillonite in Example 3 is adjusted to 2.5 parts, and the other raw materials, parameters and preparation process are the same as Example 3.
[0077] The performance of the hot melt pressure-sensitive adhesives obtained in Examples 1 to 3 and Comparative Examples 1 to 5 was tested in accordance with the national standard GB / T 23457-2017. The results are shown in Table 1:
[0078] Table 1
[0079]
[0080] It can be seen from the data recorded in Table 1 that the comprehensive performance of the hot-melt pressure-sensitive adhesive obtained in Examples 1-3 is better than that in Comparative Examples 1-5, indicating that the hot-melt pressure-sensitive adhesive prepared in the present invention not only has excellent initial peel strength, but also has a peel strength of ≥3.5N / mm with the post-cast cement mortar covered with sand under standard conditions, and maintains a relatively high bonding strength after hot air aging (80°C×168h) and water immersion (23°C×168h) treatment, and has good heat resistance.
[0081] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.
[0082] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A hot melt pressure sensitive adhesive, characterized in that: It includes the following raw materials in parts by weight: SIS thermoplastic elastomer 30 parts, plasticizer 15-17 parts, tackifying resin 53-55 parts, organic montmorillonite 1-2 parts, cross-linking component 0.5-3 parts, initiator 0.05-0.3 parts; The organized montmorillonite is montmorillonite modified by a quaternary ammonium salt cationic intercalation agent; The cross-linking component is itaconic acid hyperbranched polyester.
2. A hot melt pressure sensitive adhesive according to claim 1, characterized in that: The quaternary ammonium salt cationic intercalant is prepared by the following steps: Add caffeic acid and p-toluenesulfonic acid into DMF, stir evenly, then add DMF solution of terminal hydroxyl alkyl long-chain quaternary ammonium salt, stir and react at 90° C. for 6-8 hours, and remove DMF by rotary evaporation to obtain a quaternary ammonium salt cationic intercalation agent.
3. A hot melt pressure sensitive adhesive according to claim 2, characterized in that: The molar ratio of caffeic acid to terminal hydroxyl alkyl long-chain quaternary ammonium salt is 2:1, and the amount of p-toluenesulfonic acid used is 0.2-0.4% of the mass of caffeic acid.
4. A hot melt pressure sensitive adhesive according to claim 1, characterized in that: The terminal hydroxyl alkyl long-chain quaternary ammonium salt is at least one of dodecylmethyldihydroxyethylammonium bromide, tetradecylmethyldihydroxyethylammonium bromide, hexadecylmethyldihydroxyethylammonium bromide, di(hydroxyethyl)methyldodecylammonium chloride, octadecylmethyldihydroxyethylammonium bromide and octadecylbishydroxyethylmethylammonium chloride.
5. A hot melt pressure sensitive adhesive according to claim 1, characterized in that: The preparation method of the cross-linking component comprises the following steps: Itaconic acid, trimethylolpropane, 1,4-dioxane and p-toluenesulfonic acid are mixed, the temperature is raised to 90-100° C., the mixture is stirred for reaction for 8 hours, and 1,4-dioxane is removed by vacuum distillation to obtain a cross-linking component.
6. A hot melt pressure sensitive adhesive according to claim 5, characterized in that: The preparation method of the cross-linking component comprises the following steps: the molar ratio of itaconic acid to trimethylolpropane is 3.5-4.0:2, the amount of 1,4-dioxane is 8-10 times the mass sum of itaconic acid and trimethylolpropane, and the amount of p-toluenesulfonic acid is 0.5-1% of the mass sum of itaconic acid and trimethylolpropane.
7. A hot melt pressure sensitive adhesive according to claim 1, characterized in that: The SIS thermoplastic elastomer is SIS-1716 produced by Sinopec Baling Petrochemical Co., Ltd., and the plasticizer is at least one of liquid paraffin, naphthenic oil KN-4010 and liquid polyisobutylene PB-950.
8. A hot melt pressure sensitive adhesive according to claim 1, characterized in that: The tackifying resin is at least one of hydrogenated terpene, C5 petroleum resin and hydrogenated C5 petroleum resin.
9. A hot melt pressure sensitive adhesive according to claim 1, characterized in that: The initiator is at least one of benzoyl peroxide, potassium persulfate and azobisisobutyronitrile.
10. A process for producing a hot melt pressure sensitive adhesive according to any one of claims 1 to 9, characterized in that: The following steps are involved: Weigh the materials according to the formula, add SIS thermoplastic elastomer and plasticizer into a vacuum reactor, heat up to 145-155°C under nitrogen protection, stir for 30 minutes, add organic montmorillonite, cross-linking component and initiator, continue stirring for 30-60 minutes, finally add tackifying resin, heat up to 150-160°C, stir for 40-60 minutes, discharge while hot, and treat at a constant temperature of 25°C for 24 hours to obtain a hot melt pressure-sensitive adhesive.