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CN-121991624-A - Environment-friendly polyurethane structural adhesive and preparation method thereof

CN121991624ACN 121991624 ACN121991624 ACN 121991624ACN-121991624-A

Abstract

The invention belongs to the technical field of structural adhesives, and discloses an environment-friendly polyurethane structural adhesive and a preparation method thereof. The environment-friendly polyurethane foam is prepared by innovatively adding 30 parts of polyether polyol, 50 parts of isocyanate, 20 parts of environment-friendly diluent, 3-5 parts of environment-friendly toughening agent, 1-2 parts of bio-based anti-aging agent and 0.5-1 part of silane coupling agent into a basic system of which the polyether polyol, the isocyanate and the diluent are used as basic systems. The structural adhesive prepared by the invention has no release of harmful substances such as formaldehyde, benzene series and the like, has higher bonding strength, excellent flexibility, aging resistance and substrate suitability, has simple and environment-friendly preparation process, can be widely applied to the fields of furniture manufacture, plate bonding, construction and the like, and has remarkable practicability and market prospect.

Inventors

  • ZHAO QIANG
  • ZHANG DIANCHENG
  • SHEN BIN
  • FAN YEBIN
  • WANG WANG

Assignees

  • 江苏汉脉科技发展有限公司

Dates

Publication Date
20260508
Application Date
20251230

Claims (8)

  1. 1. The environment-friendly polyurethane structural adhesive is characterized by comprising, by mass, 30 parts of polyether polyol, 50 parts of isocyanate, 20 parts of environment-friendly diluent, 3-5 parts of environment-friendly toughening agent, 1-2 parts of bio-based anti-aging agent and 0.5-1 part of silane coupling agent.
  2. 2. The environment-friendly polyurethane structural adhesive according to claim 1, wherein the isocyanate is polymethylene polyphenyl isocyanate, and the environment-friendly diluent is dimethyl carbonate or ethyl acetate.
  3. 3. The environment-friendly polyurethane structural adhesive of claim 1, wherein the environment-friendly toughening agent is polycarbonate diol or polycaprolactone diol, and has a number average molecular weight of 1000-2000.
  4. 4. The environment-friendly polyurethane construction adhesive of claim 1, wherein the bio-based anti-aging agent is tea polyphenol or rosemary extract.
  5. 5. The environment-friendly polyurethane structural adhesive of claim 1, wherein the silane coupling agent is gamma-aminopropyl triethoxysilane or gamma-glycidoxypropyl trimethoxysilane.
  6. 6. The method for preparing the environment-friendly polyurethane structural adhesive according to any one of claims 1 to 5, which is characterized by comprising the following steps: (1) Pretreating polyether polyol, isocyanate, an environment-friendly diluent, an environment-friendly toughening agent, a bio-based anti-aging agent and a silane coupling agent in a cool, dry and well ventilated environment respectively to ensure that the moisture content of each component is lower than 0.3%; (2) Adding the pretreated polyether polyol into a reaction kettle under the protection of nitrogen, controlling the temperature to be 40-45 ℃, slowly adding isocyanate, stirring while adding, wherein the stirring speed is 350-450r/min, and the stirring time is 40-50 minutes, so as to form a prepolymer; (3) Adding functional components, namely sequentially adding an environment-friendly toughening agent and a bio-based anti-aging agent into the prepolymer in the step (2), heating to 50-55 ℃, and continuously stirring for 30-40 minutes to fully disperse the functional components; (4) Regulating and modifying, namely cooling to below 40 ℃, adding an environment-friendly diluent and a silane coupling agent, stirring for 25-35 minutes, ensuring uniform system mixing, and regulating the viscosity to a target range; (5) And (3) treating a finished product, namely filtering and removing impurities from the product obtained in the step (4) through a 5-8 mu m precision filter, and packaging by adopting a sealed steel or galvanized iron bucket or ton bucket (IBC) to obtain the environment-friendly polyurethane structural adhesive finished product.
  7. 7. The method for preparing environment-friendly polyurethane structural adhesive as claimed in claim 6, wherein in the steps (2) - (4), a dry and anhydrous environment is maintained in the reaction kettle, so that side reactions of water and isocyanate are avoided.
  8. 8. The method of claim 7, wherein in the step (3), the environmental-friendly toughening agent and the bio-based anti-aging agent are added in a divided manner, wherein the addition amount of each time is not more than 50% of the total mass, and the interval is 10 minutes.

Description

Environment-friendly polyurethane structural adhesive and preparation method thereof Technical Field The invention relates to the technical field of structural adhesives, in particular to an environment-friendly polyurethane structural adhesive and a preparation method thereof. Background The structural adhesive is used as a high-strength bonding material, is widely applied in the fields of furniture manufacture, plate bonding, construction and the like, and the environmental protection and the comprehensive performance of the structural adhesive are directly related to the quality of products, the health of human bodies and the safety of the environment. Meanwhile, part of environment-friendly polyurethane structural adhesives can meet the formaldehyde-free requirement, but have the problems of insufficient bonding strength, poor flexibility, limited ageing resistance, poor suitability for different base materials and the like, and are difficult to achieve both environment friendliness and usability. In the prior art, although attempts are made to improve the performance of the structural adhesive by adding functional additives, part of the additives have the problems of VOC emission, poor biocompatibility and the like, but the environmental protection of products is reduced, and the additives and a basic system have insufficient synergism, so that the performance superposition effect is poor. Therefore, the structural adhesive based on an environment-friendly raw material system is developed, and the environment-friendly and high-strength, high-flexibility, aging-resistant and high-adaptability collaborative lifting structural adhesive is realized by scientifically adding the environment-friendly functional auxiliary agent, so that the structural adhesive has important practical significance. Disclosure of Invention The invention aims to provide an environment-friendly polyurethane structural adhesive and a preparation method thereof, and the environment-friendly polyurethane structural adhesive and the preparation method thereof solve the problems in the background technology. The environment-friendly polyurethane structural adhesive comprises, by mass, 30 parts of polyether polyol, 50 parts of isocyanate, 20 parts of an environment-friendly diluent, 3-5 parts of an environment-friendly toughening agent, 1-2 parts of a bio-based anti-aging agent and 0.5-1 part of a silane coupling agent. Preferably, the isocyanate is polymethylene polyphenyl isocyanate, and the environment-friendly diluent is dimethyl carbonate or ethyl acetate. Preferably, the environment-friendly toughening agent is polycarbonate diol or polycaprolactone diol, and the number average molecular weight is 1000-2000. Preferably, the bio-based anti-aging agent is tea polyphenol or rosemary extract. Preferably, the silane coupling agent is gamma-aminopropyl triethoxysilane or gamma-glycidoxypropyl trimethoxysilane. The preparation method of the environment-friendly polyurethane structural adhesive comprises the following steps: (1) Pretreating polyether polyol, isocyanate, an environment-friendly diluent, an environment-friendly toughening agent, a bio-based anti-aging agent and a silane coupling agent in a cool, dry and well ventilated environment respectively to ensure that the moisture content of each component is lower than 0.3%; (2) Adding the pretreated polyether polyol into a reaction kettle under the protection of nitrogen, controlling the temperature to be 40-45 ℃, slowly adding isocyanate, stirring while adding, wherein the stirring speed is 350-450r/min, and the stirring time is 40-50 minutes, so as to form a prepolymer; (3) Adding functional components, namely sequentially adding an environment-friendly toughening agent and a bio-based anti-aging agent into the prepolymer in the step (2), heating to 50-55 ℃, and continuously stirring for 30-40 minutes to fully disperse the functional components; (4) Regulating and modifying, namely cooling to below 40 ℃, adding an environment-friendly diluent and a silane coupling agent, stirring for 25-35 minutes, ensuring uniform system mixing, and regulating the viscosity to a target range; (5) And (3) treating a finished product, namely filtering and removing impurities from the product obtained in the step (4) through a 5-8 mu m precision filter, and packaging by adopting a sealed steel or galvanized iron bucket or ton bucket (IBC) to obtain the environment-friendly polyurethane structural adhesive finished product. Preferably, in the steps (2) - (4), the reaction kettle is kept in a dry and anhydrous environment, so that side reactions of water and isocyanate are avoided. Preferably, in the step (3), the environment-friendly toughening agent and the bio-based anti-aging agent are added in a divided manner, wherein the addition amount of each time is not more than 50% of the total mass, and the interval is 10 minutes. By adopting the technical scheme, the invention has the beneficial effects