Epoxy glue slow-binding agent with temperature control performance

Abstract

The invention belongs to the technical field of epoxy adhesives, and particularly relates to an epoxy adhesive slow-binding agent with temperature control performance. The epoxy glue slow-binding agent is prepared from the following raw materials in parts by weight: 100 parts of epoxy resin; 60-80 parts of an organic phase change material; 40 to 60 parts of filler; 10-30 parts of a curing agent; 10 parts of a diluent; and 10 parts of carboxyl-terminated liquid nitrile rubber. According to the invention, the carboxyl-terminated liquid nitrile rubber is used as a flexibilizer to enhance the flexibility of the epoxy adhesive slow-adhesion agent, and the moisture latent curing agent and the organic phase change material are used, so that the pot life of the slow-adhesion agent can be prolonged and the curing period can be shortened by utilizing the heat storage and heat release of the phase change material; and the engineering requirements of long working life and short curing period of the retard-bonded prestressed tendon can be met.

Description

Technical Field

[0001] The invention belongs to the technical field of epoxy adhesives, and in particular relates to an epoxy adhesive retarding agent with temperature control performance. Background Art

[0002] The core of the slow-bonding prestressing technology is to press the prestressed tendons, slow-bonding agent and outer sheath together into slow-bonding prestressed tendons through modern production technology. The slow-bonding agent plays a vital role in the construction of prestressed components. It can reduce stress concentration, stress release and deformation and cracks of prestressed components during the construction process, and improve the durability, earthquake resistance, stability and service life of prestressed components.

[0003] At present, all slow-binders are epoxy resins. The reaction heat released during the curing process of epoxy resins is difficult to control, and the released reaction heat will accelerate the curing of epoxy resins, greatly shortening their pot life. Therefore, it is difficult to meet the urgent control requirements of long pot life and short curing period in modern engineering construction.

[0004] Therefore, under the premise of ensuring performance, a new epoxy adhesive retarder with a long tensioning application period and a short curing period is developed. This retarder should maintain a long application period, and secondly, after the prestressed tendon tensioning construction, it can be cured within a few days to meet the required mechanical properties. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing an epoxy adhesive retarder with temperature control performance. The epoxy adhesive retarder uses a moisture latent curing agent, adds an appropriate amount of filler and terminal carboxyl liquid nitrile rubber, meets the performance of the adhesive after curing, and adds an organic phase change material. The preparation process is simple and the cost is low. It is used to solve the technical problems of short application period and long curing period of epoxy adhesive retarder.

[0006] The technical solution of the present invention is: A temperature-controlling epoxy adhesive retarder comprises the following components by weight: 100 parts of epoxy resin; 60-80 parts of organic phase change material; 40-60 parts of mixed filler; 10-30 parts of curing agent; 10 parts of diluent; and 10 parts of carboxyl-terminated liquid nitrile rubber.

[0007] As a preferred technical method of the present invention, the epoxy resin is a carboxyl-terminated liquid nitrile rubber modified bisphenol A type epoxy resin, wherein the bisphenol A type epoxy resin model is one or more of E-51 and E-44.

[0008] As a preferred technical method of the present invention, the mixed filler is one or more of wollastonite and cement.

[0009] As a preferred technical method of the present invention, the organic phase change material is one or more of n-eicosane and paraffin.

[0010] As a preferred technical method of the present invention, the curing agent is one or more of polyamide 650 resin and ketimine.

[0011] As a preferred technical method of the present invention, the diluent is prepared by mixing dibutyl phthalate and diluent 501 in a mixing ratio of 1:1.

[0012] A method for preparing an epoxy adhesive retarder with temperature control performance comprises the following steps: S1. The bisphenol A epoxy resin and the carboxyl-terminated liquid nitrile rubber were mechanically stirred at a speed of 800 r / min in a constant temperature oil bath at 120°C for 1.5 h to pre-react the epoxy resin and the carboxyl-terminated liquid nitrile rubber, and then cooled to room temperature to obtain a modified epoxy resin.

[0013] S2. Place the organic phase change material in a beaker and slowly heat it to 60°C in a water bath, stirring it magnetically at 500 r / min for 1 h. After the organic phase change material is completely melted, a viscous liquid is obtained.

[0014] S3, adding the modified epoxy resin to the viscous liquid of step S2, continuing stirring for 5 min, then adding the diluent, filler, and curing agent in sequence, stirring and mixing evenly, and placing at room temperature for 24 h to obtain an epoxy adhesive slow-adhesive agent with temperature control performance.

[0015] The beneficial effects of the present invention are: (1) The epoxy adhesive retarder with temperature control performance provided by the present invention delays the curing time by absorbing the reaction heat released during the tension application period of the epoxy adhesive retarder through an organic phase change material. At the same time, the stored heat can be released during the curing period to accelerate the curing time, thereby solving the technical problem of the short application period and long curing period of the epoxy adhesive retarder.

[0016] (2) The epoxy adhesive retarder with temperature control performance provided by the present invention uses a carboxyl-terminated liquid nitrile rubber to toughen the epoxy resin matrix, thereby improving the tensile toughness of the adhesive, ensuring that the adhesive system will not undergo brittle fracture under the action of external forces after curing, and enhancing the impact performance of the adhesive system. DETAILED DESCRIPTION

[0017] For the convenience of comparison, the experimental results are listed in Table 1.

[0018] This embodiment provides a temperature-controlled high-performance epoxy adhesive retarder, comprising the following steps: [Example 1]: S1. 25 parts of bisphenol A epoxy resin E-44, 75 parts of bisphenol A epoxy resin E-51 and 10 parts of carboxyl-terminated liquid nitrile rubber were mechanically stirred at a speed of 800 r / min for 1.5 h in a constant temperature oil bath at 120°C to pre-react the epoxy resin with the carboxyl-terminated liquid nitrile rubber, and then cooled to room temperature to obtain a modified epoxy resin.

[0019] S2. Put 60 parts of paraffin wax into a beaker and slowly heat it to 60°C in a water bath. Stir it with a magnetic stirrer at a speed of 500 r / min for 1 h. After the paraffin wax is completely melted, a viscous liquid is obtained.

[0020] S3, adding the modified epoxy resin to the viscous liquid of step S2, continuing stirring for 5 min, then adding 10 parts of diluent, 40 parts of cement, 6 parts of polyamide 650 resin curing agent and 18 parts of ketimine curing agent in sequence, stirring and mixing evenly, and placing at room temperature for 24 h to obtain an epoxy adhesive retarder with temperature control performance.

[0021] [Example 2]: S1. 25 parts of bisphenol A epoxy resin E-44, 75 parts of bisphenol A epoxy resin E-51 and 10 parts of carboxyl-terminated liquid nitrile rubber were mechanically stirred at a speed of 800 r / min for 1.5 h in a constant temperature oil bath at 120°C to pre-react the epoxy resin with the carboxyl-terminated liquid nitrile rubber, and then cooled to room temperature to obtain a modified epoxy resin.

[0022] S2. Put 70 parts of paraffin wax into a beaker and slowly heat it to 60°C in a water bath. Stir it with a magnetic stirrer at a speed of 500 r / min for 1 h. After the paraffin wax is completely melted, a viscous liquid is obtained.

[0023] S3, adding the modified epoxy resin to the viscous liquid of step S2, continuing stirring for 5 min, then adding 10 parts of diluent, 40 parts of cement, 6 parts of polyamide 650 resin curing agent and 18 parts of ketimine curing agent in sequence, stirring and mixing evenly, and placing at room temperature for 24 hours to obtain an epoxy adhesive slow-adhesive agent with temperature control performance.

[0024] [Example 3]: S1. 25 parts of bisphenol A epoxy resin E-44, 75 parts of bisphenol A epoxy resin E-51 and 10 parts of carboxyl-terminated liquid nitrile rubber were mechanically stirred at a speed of 800 r / min for 1.5 h in a constant temperature oil bath at 120°C to pre-react the epoxy resin with the carboxyl-terminated liquid nitrile rubber, and then cooled to room temperature to obtain a modified epoxy resin.

[0025] S2. Put 80 parts of paraffin wax into a beaker and slowly heat it to 60°C in a water bath. Stir it with a magnetic stirrer at a speed of 500 r / min for 1 h. After the paraffin wax is completely melted, a viscous liquid is obtained.

[0026] S3, adding the modified epoxy resin to the viscous liquid of step S2, continuing stirring for 5 min, then adding 10 parts of diluent, 40 parts of cement, 6 parts of polyamide 650 resin curing agent and 18 parts of ketimine curing agent in sequence, stirring and mixing evenly, and placing at room temperature for 24 h to obtain an epoxy adhesive retarder with temperature control performance.

[0027] [Example 4]: S1. 25 parts of bisphenol A epoxy resin E-44, 75 parts of bisphenol A epoxy resin E-51 and 10 parts of carboxyl-terminated liquid nitrile rubber were mechanically stirred at a speed of 800 r / min for 1.5 h in a constant temperature oil bath at 120°C to pre-react the epoxy resin with the carboxyl-terminated liquid nitrile rubber, and then cooled to room temperature to obtain a modified epoxy resin.

[0028] S2. Put 80 parts of paraffin wax into a beaker and slowly heat it to 60°C in a water bath. Stir it with a magnetic stirrer at a speed of 500 r / min for 1 h. After the paraffin wax is completely melted, a viscous liquid is obtained.

[0029] S3, adding the modified epoxy resin to the viscous liquid of step S2, continuing stirring for 5 min, then adding 10 parts of diluent, 50 parts of cement, 6 parts of polyamide 650 resin curing agent and 18 parts of ketimine curing agent in sequence, stirring and mixing evenly, and placing at room temperature for 24 h to obtain an epoxy adhesive retarder with temperature control performance.

[0030] [Example 5]: S1. 25 parts of bisphenol A epoxy resin E-44, 75 parts of bisphenol A epoxy resin E-51 and 10 parts of carboxyl-terminated liquid nitrile rubber were mechanically stirred at a speed of 800 r / min for 1.5 h in a constant temperature oil bath at 120°C to pre-react the epoxy resin with the carboxyl-terminated liquid nitrile rubber to obtain a modified epoxy resin.

[0031] S2. Put 80 parts of n-eicosane into a beaker and slowly heat it to 60°C in a water bath. Stir it with a magnetic stirrer at a speed of 500 r / min for 1 h. After the n-eicosane is completely melted, a viscous liquid is obtained.

[0032] S3, adding the modified epoxy resin to the viscous liquid of step S2, continuing stirring for 5 min, then sequentially adding 10 parts of diluent, 40 parts of cement, 10 parts of wollastonite, 6 parts of polyamide 650 resin curing agent and 18 parts of ketimine curing agent, stirring and mixing evenly, and placing at room temperature for 24 h to obtain an epoxy adhesive retarder with temperature control performance.

[0033] [Comparative Example 1]: This comparative example provides an epoxy adhesive retarder without temperature control performance, which is different from Example 1 only in that no organic phase change material is added, and includes the following steps: S1. 25 parts of bisphenol A epoxy resin E-44, 75 parts of bisphenol A epoxy resin E-51 and 10 parts of carboxyl-terminated liquid nitrile rubber were mechanically stirred at a speed of 800 r / min for 1.5 h in a constant temperature oil bath at 120°C to pre-react the epoxy resin with the carboxyl-terminated liquid nitrile rubber to obtain a modified epoxy resin.

[0034] S2. Add 10 parts of diluent, 40 parts of cement, 6 parts of polyamide 650 resin curing agent and 18 parts of ketimine curing agent to the modified epoxy resin in sequence, stir and mix evenly, and place at room temperature for 24 hours to obtain an epoxy adhesive retarder without temperature control performance.

[0035] project Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Tension applicable period / day 101 121 134 129 125 83 Appearance Uniform texture, no impurities or bubbles Uniform texture, no impurities or bubbles Uniform texture, no impurities or bubbles Uniform texture, no impurities or bubbles Uniform texture, no impurities or bubbles Uniform texture, no impurities or bubbles Bending strength / 28.34 29.85 28.38 33.29 34.48 28.75 Compressive strength / 75.44 76.01 75.78 82.75 80.43 75.32 Tensile strength / 28.87 28.39 27.95 32.68 31.92 28.17 Heat and humidity aging resistance Tensile shear strength decreased by <3% Tensile shear strength decreased by <3% Tensile shear strength decreased by <3% Tensile shear strength decreased by <3% Tensile shear strength decreased by <2% Tensile shear strength decreased by <3% It can be seen from the above test results that the epoxy adhesive retarder prepared using the embodiments of the present invention all have excellent mechanical properties, among which Example 4 is the most outstanding, having a uniform texture, free of impurities and bubbles, and having a bending strength of 33.29, a compressive strength of 82.75, and a tensile strength of 32.68, all of which are improved differently compared to Comparative Example 1.

[0036] In Example 5, wollastonite was added as filler in addition to cement to improve the mechanical strength of the epoxy adhesive, and its bending strength was 34.48, compressive strength was 80.43, and tensile strength was 31.92. This is because wollastonite is an inorganic needle-shaped mineral with the advantages of being non-toxic, resistant to chemical corrosion, good thermal stability and dimensional stability, and excellent mechanical properties, and is very suitable for use as a reinforcing filler for polymer-based composite materials.

[0037] Due to the addition of organic phase change material, the tensile application period of Examples 1 to 5 is longer than that of the control. In Example 1, the duration of treatment was extended for different periods of time, namely 18 days, 38 days, 51 days, 46 days and 42 days, and the duration was gradually extended with the increase of dosage, and there was no significant effect on the mechanical properties.

[0038] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An epoxy adhesive retarder with temperature control performance, characterized in that: By weight, it includes the following components: Epoxy resin: 100 parts; Organic phase change material: 60~80 parts; Mixed filler: 40~60 parts; Curing agent: 10~30 parts; Diluent: 10 parts; Carboxyl-terminated liquid nitrile rubber: 10 parts.

2. The epoxy adhesive retarder with temperature control performance according to claim 1, characterized in that: The epoxy resin is a carboxyl-terminated liquid nitrile rubber modified bisphenol A type epoxy resin, wherein the bisphenol A type epoxy resin model is one or more of E-51 and E-44.

3. The epoxy adhesive retarder with temperature control performance according to claim 1, characterized in that: The mixed filler is one or more of wollastonite and cement.

4. The epoxy adhesive retarder with temperature control performance according to claim 1, characterized in that: The organic phase change material is one or more of n-eicosane and paraffin.

5. The epoxy adhesive retarder with temperature control performance according to claim 1, characterized in that: The curing agent is one or more of polyamide 650 resin and ketimine.

6. The epoxy adhesive retarder with temperature control performance according to claim 1, characterized in that: The diluent is prepared by mixing dibutyl phthalate and diluent 501 in a ratio of 1:

1.

7. The method for preparing an epoxy adhesive retarder with temperature control performance according to claim 1, characterized in that: The following steps are involved: S1. Mechanically stir bisphenol A epoxy resin and carboxyl-terminated liquid nitrile rubber in a 120°C constant temperature oil bath at a speed of 800 r / min for 1.5 h to pre-react the epoxy resin and the carboxyl-terminated liquid nitrile rubber, and then cool to room temperature to obtain a modified epoxy resin. S2. Put the organic phase change material into a beaker and slowly heat it to 60°C in a water bath. During this period, magnetically stir it at a speed of 500 r / min for 1 h. After the organic phase change material is completely melted, a viscous liquid is obtained. S3. Add the modified epoxy resin to the viscous liquid in step S2, continue stirring for 5 min, then add the diluent, filler, and curing agent in turn, stir and mix evenly, and place it at room temperature for 24 h to obtain an epoxy adhesive slow-adhesive with temperature control performance.