CN112126386A

CN112126386A - Low-temperature-resistant refrigerating pipeline sealant and preparation method and application thereof

Info

Publication number: CN112126386A
Application number: CN202011014643.3A
Authority: CN
Inventors: 粟再祥; 马交军
Original assignee: Shaoyang Brothers New Material Technology Co ltd
Current assignee: Shaoyang Brothers New Material Technology Co ltd
Priority date: 2020-09-24
Filing date: 2020-09-24
Publication date: 2020-12-25

Abstract

The invention provides a low-temperature-resistant refrigerating pipeline sealant and a preparation method and application thereof, wherein the sealant comprises, by weight, 30% -40% of elastic resin, 35% -50% of acrylate monomer, 3% -5% of accelerator, 2% -5% of coupling agent, 8% -10% of nano toughening agent, 0.5% -1% of stabilizer, 2% -3% of initiator and 0.25% -0.5% of pigment. The sealant can still keep good flexibility at ultralow temperature, has high curing speed and good low-temperature resistance effect, does not crack or become brittle even when the adhesive film is repeatedly folded at 180 degrees at minus 50 ℃, and has stable bonding force and impact resistance on metal pipelines.

Description

Low-temperature-resistant refrigerating pipeline sealant and preparation method and application thereof

Technical Field

The invention relates to the field of industrial sealing materials, in particular to a low-temperature-resistant sealing agent for a refrigeration pipeline, and a preparation method and application thereof.

Background

The anaerobic sealant used in the prior common refrigeration equipment pipeline industrial material in China stimulates skin to be harmful to health, has long curing time and crisp curing property, is easy to crack a glue layer at the low temperature of 50 ℃ below zero, causes the pipeline to leak, and loses the original toughness of the glue film, the adhesive force to the pipe and the impact resistance. At present, the product in the field is blank, the refrigeration pipeline anaerobic adhesive is imported, the foreign product technology is in monopoly status, the price is high, the shortage condition often appears, and a lot of troubles and economic losses are brought to various domestic matched manufacturers. Because the sealant used on the refrigeration pipeline is in a low-temperature environment for a long time and is easy to age or crack at low temperature, the development of the pipeline bonding sealing material for the refrigeration equipment is necessary to solve the problems that the refrigeration pipeline sealing material is easy to age and cannot resist low temperature.

Disclosure of Invention

The anaerobic adhesive product is solidified by the principle that gel is quickly generated under the catalysis of metal ions under the condition of small gaps and oxygen deficiency, so that the mutual bonding effect of metals on two sides is realized. Aiming at the product performance requirements in the existing industrial production, the invention aims to provide the low-temperature-resistant refrigerating pipeline sealant which does not contain components having adverse effects on human bodies and the environment, is high in curing speed, can keep good toughness of a cured product at-50 ℃, can be repeatedly folded at 180 degrees at ultralow temperature without cracking or damaging an adhesive film, and has stable adhesive force and impact resistance on metal pipelines.

In order to achieve the purpose, the technical scheme of the invention is as follows:

the low-temperature-resistant refrigerant pipeline sealant comprises the following components in percentage by weight:

in some embodiments, the low temperature resistant refrigerant pipe sealant is prepared from the following components in percentage by weight:

in some embodiments, the nano toughener is one or a mixture of two or more of nano polyetherimide particles, nano polyetheretherketone particles and nano nitrile rubber particles, and the particle size of the nano toughener is 20nm to 100nm, preferably 50nm to 70 nm.

In some embodiments, the elastic resin comprises one or a mixture of two or more of multifunctional aromatic urethane acrylate, difunctional aliphatic urethane acrylate, epoxy modified urethane oligomer and epoxy modified acrylic oligomer with a metal ion treatment agent, and preferably one or a mixture of two or more of multifunctional aromatic urethane acrylate, difunctional aliphatic urethane acrylate, epoxy modified urethane oligomer and epoxy modified acrylic oligomer with a metal ion treatment agent.

In some embodiments, the acrylate monomer comprises one or more of hydroxypropyl methacrylate, triethylene glycol methacrylate, tetraethylene glycol dimethacrylate, ethoxylated bisphenol a dimethacrylate, and trimethylolpropane methacrylate, preferably one or more of hydroxypropyl methacrylate, triethylene glycol methacrylate, tetraethylene glycol dimethacrylate, ethoxylated bisphenol a dimethacrylate, and trimethylolpropane trimethacrylate.

In some embodiments, the promoter comprises one or a mixture of more than two of acetophenone hydrazine, o-benzoylsulfonimide (saccharin), ascorbic acid and tri-n-butylamine, and preferably one or a mixture of two of acetophenone hydrazine, saccharin, ascorbic acid and tri-n-butylamine.

In some embodiments, the initiator comprises one or a mixture of two or more of cumene hydroperoxide, tert-butyl hydroperoxide and low-odor dicumyl peroxide, preferably one or a mixture of two or more of cumene hydroperoxide, tert-butyl hydroperoxide and low-odor dicumyl peroxide.

In some embodiments, the stabilizer comprises one or a mixture of two or more of hydroquinone, p-hydroxyanisole and p-benzoquinone, preferably one or a mixture of two or more of hydroquinone, p-hydroxyanisole and p-benzoquinone.

The preparation method of the low-temperature-resistant refrigerating pipeline sealant comprises the following steps:

s1: accurately weighing each raw material for later use;

s2: sequentially adding the prepared elastic resin, acrylate monomer, accelerator, coupling agent, nano toughening agent and stabilizer into a reaction vessel preheated to 50-55 ℃;

s3: starting the reaction container to stir, controlling the temperature to be 50-55 ℃, starting the materials to react, forming a prepolymer after the reaction is finished, and cooling the prepolymer in the reaction container to be below 40 ℃;

s4: sequentially adding prepared initiator and pigment into the cooled prepolymer;

s5: and starting the reaction kettle for stirring, controlling the temperature to be 35-40 ℃, discharging after the specified time is reached, and thus obtaining the low-temperature-resistant refrigerating pipeline sealant.

The invention aims to provide the application of the low-temperature-resistant refrigerating pipeline sealant or the low-temperature-resistant refrigerating pipeline sealant prepared by the preparation method in a metal pipeline system of refrigerating equipment. The low-temperature-resistant refrigeration pipeline sealant or the low-temperature-resistant refrigeration pipeline sealant prepared by the preparation method can be applied to metal pipeline systems of temperature regulation equipment such as high-speed rails, airplanes, tanks, new energy vehicles, air conditioner production lines, air conditioner installation, seafood machines, cold (warm) water machines, refrigeration water dispensers, refrigerant media and the like.

Compared with the prior art, the invention has the following main characteristics:

the invention takes elastic resin as matrix resin, has necessary elasticity and impact resistance, takes acrylate monomer as a modified material, can react with the matrix resin, improves the crosslinking degree and the material strength of the matrix resin, adds a reactive particle toughening agent with nanometer size, can greatly strengthen the micro-mechanical structure of a cured product, absorbs energy generated by external force through self deformation and silver line induction when the material is subjected to the external force, prevents further development of destructive defects, has huge active microstructures in unit volume, can absorb a large amount of energy acted by the external force, thereby endowing the cured product with important functions of high strength and high toughness, and can increase various process properties of the product by adding proper amounts of accelerating agent, initiating agent, coupling agent, stabilizing agent and pigment as auxiliary materials. The main sources of good toughness of the material composite structure are: the molecular chain of the nano toughener contains active groups capable of reacting with matrix resin, and the active groups react with matrix materials to form a network structure; the addition of the acrylate monomer provides a part of flexible chains, which can reduce the brittleness of the matrix material and improve the impact resistance of the composite material. In addition, the accelerator selected by the scheme can accelerate the curing speed of the product, and the coupling agent selected can improve the permeability and the adhesive force of the product, so that the product can permeate in small gaps; the addition of the initiator can accelerate the polymerization of the molecular chains of the matrix resin and the acrylate monomer; the addition of the stabilizer can ensure that the product has storage stability; the pigment can select proper product color according to application scenes, so that the applied product is more attractive.

The preparation method provided by the invention is based on the principle that: the preparation method comprises the steps of firstly reacting the elastic resin, the acrylate monomer, the accelerator, the nano toughener, the coupling agent and the stabilizer at 50-55 ℃ to enable the components to be compounded and dissolved and react, then cooling to 40 ℃, adding the initiator and the pigment to mix, reacting at 35-40 ℃ to promote the components to be uniformly mixed, and then discharging. It is to be emphasized that: when the initiator is added, if the temperature is higher, decomposition may occur or the polymerization reaction between the components is accelerated or implode, and the ideal effect cannot be achieved, so that the temperature needs to be reduced to a proper range to keep the reaction system smooth, and the sealant product of the scheme has excellent performances of toughness, impact resistance and low temperature resistance.

Compared with the prior art, the invention has the following effective effects:

1. the product of the invention is added with the reactive particle nano flexibilizer with nano size, and can greatly strengthen the micro mechanical structure of the cured product. The high-flexibility high-temperature-resistant refrigeration pipeline can still keep good flexibility in an extremely low temperature (-50 ℃) environment, an adhesive film of a cured product is repeatedly folded at 180 degrees and cannot be cracked or damaged, stable adhesive force and impact resistance are provided for a metal pipeline, and the refrigeration pipeline is ensured not to leak and fall off.

2. The permeability is good, the sealant is dripped on the surface of the pipe end, and the sealant can quickly permeate into the butt joint gap of the pipeline and is automatically cured, so that the effect of complete sealing is achieved.

3. The sealing agent of the invention does not corrode other materials, and the service life of the pipeline sealed by the sealing agent of the invention is long and can exceed the service life of equipment.

4. The curing speed is high, the sealant is suitable for various metal materials, can be conveniently used without special cleaning of pipelines, and can be cured within 3-8 min at normal temperature.

5. The quick-acting adhesive tape has quick response, and can be put into use immediately after the pipelines are butted due to the coexistence of the bonding and sealing effects of the product, so that the working efficiency is greatly improved.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, but rather should be construed as broadly as the present invention is capable of modification in various respects, all without departing from the spirit and scope of the present invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Example 1

wherein the average particle diameter of the styrene-butadiene rubber particles is 50-70 nm.

The preparation method of the low-temperature-resistant refrigerant pipeline sealant comprises the following steps:

s1: accurately weighing the raw materials of each component for later use;

s2: sequentially adding the prepared difunctional aliphatic polyurethane acrylate S1, hydroxypropyl methacrylate, saccharin, gamma-methacryloxy trimethoxy silane, styrene butadiene rubber particles and hydroquinone into a reaction kettle preheated to 50 ℃;

s3: starting the reaction kettle to stir, controlling the temperature in the reaction kettle at 50 ℃, starting the materials to react, stirring for 4 hours, finishing the reaction of the materials to form a prepolymer, and cooling the prepolymer to below 40 ℃;

s4: sequentially adding the prepared iso-phenylpropyl hydrogen peroxide and the oil-soluble blue in the S1 into the cooled prepolymer;

s5: and starting the reaction kettle again for stirring, controlling the temperature to be 35 ℃, completing the reaction after 40min of reaction, closing the reaction kettle, cooling to be below 35 ℃, and discharging to obtain the low-temperature-resistant refrigeration pipeline sealant.

Example 2

The preparation method and preparation conditions of this example were the same as those of example 1.

Comparative example 1

The composition and preparation method of the sealant of comparative example 1 were the same as those of example 1 except that the amount of butyl rubber particles was 2%.

Comparative example 2

The composition and preparation of the sealant of comparative example 2 were the same as those of example 1 except that the butyl rubber particles were used in an amount of 18%

The sealants prepared in examples 1-2 and comparative examples 1-2 were tested for curing time, adhesive film flexibility and tensile strength by the following methods:

1. determination of the curing time

The connecting pipe is made of an aluminum pipe bonded with the aluminum pipe, one side of the connecting pipe is flat, the other side of the connecting pipe is flared, sealant is dripped on the periphery of the inserted flat pipe, then the connecting pipe is inserted into the flared pipe and rotates for a circle to be static, and the time of screwing by hand is the curing time.

2. Measurement of film flexibility

Two 25X 100 copper foils (0.4mm, TP2/T2) were attached after dropping a sealant, pressed together with an aluminum plate weighing 100. + -.2 g, and after 24 hours, the copper foils were peeled off, and the films were inspected for film formation, and then folded in half at 180 ℃ repeatedly without breaking, and the specific test results of the sealants of examples 1 and 2 at different temperatures are shown in Table 2.

3. Determination of tensile Strength

The aluminum pipe cured in the test of item 1 was subjected to a test with a tensile machine after 24 hours.

The test results are shown in table 1.

TABLE 1 results of various property tests of examples 1-2 and comparative examples 1-2

	Example 1	Example 2	Comparative example 1	Comparative example 2
					Curing time 25 deg.C (min)	7	8	5	12
Flexibility of adhesive film	Superior food	Superior food	Is relatively brittle	Too soft
					Tensile Strength (N)	833	752	866	430

As shown in Table 1, the addition amount of the nano toughener can affect the curing time, the flexibility and the tensile strength of the adhesive film, the addition amount is large, the curing time of the sealant is prolonged, the adhesive film is too soft, the bonding effect is poor, and the tensile strength is poor; the addition amount is small, the curing time is short, the tensile strength is increased, but the flexibility of the adhesive film is poor, the brittleness is high at a lower temperature, and tests show that the addition amount of the nano toughening agent is 8-10%, so that the sealant has a proper curing time, the flexibility of the adhesive film is excellent, and the tensile strength is in a proper range.

TABLE 2 measurement results of flexibility of adhesive films of the sealants obtained in examples 1 to 2 at different temperatures (the adhesive films were repeatedly folded in half at 180 ℃ 100 times)

Secondly, the sealant prepared in example 1 is tested for air tightness by the following test method:

the aluminum pipe is butted with the aluminum pipe, the opening is flattened while the opening is flared, sealant is dripped around the inserted plain pipe, then the flared pipe is inserted and rotated for a circle, the pipe fitting joint is connected after standing for 20 hours, the water detection is carried out under the condition that gas pressure is applied in the pipe, the gas leakage phenomenon is observed, and the test results are shown in table 3.

Table 3 sealant hermeticity test results of example 1

Examples 3 to 4

The composition and preparation method of the sealing agent prepared in examples 3 to 4 are the same as those of example 1, except that the grain size range and average grain size of the nano toughener are shown in table 4.

TABLE 4 particle size ranges and average particle sizes of tougheners used in examples 3-4

	Example 3	Example 4
			Average particle diameter	20-50	80-100

The sealants prepared in examples 3 to 4 were subjected to the related performance tests, and the test results are shown in table 5.

Table 5 examples 3-4 sealant performance test results

As shown in tables 3 and 5, when the grain size of the nano toughener is between 50nm and 70nm, the prepared sealant has excellent performances and can be applied to occasions with higher requirements on air tightness.

Example 5

The low-temperature-resistant refrigerating pipeline sealant comprises the following components in percentage by weight:

wherein the average particle diameter of the polyimide particles is 80-100 nm.

The preparation of the sealant of this example included the following steps:

s1: accurately weighing the raw materials of each component for later use;

s2: sequentially adding polyfunctional group aromatic, triethylene glycol methacrylate, acetyl phenylhydrazine, gamma-methacryloxy trimethoxy silane, polyetherimide and hydroquinone into a reaction kettle preheated to 55 ℃;

s3: starting the reaction kettle for stirring, controlling the temperature to be 55 ℃, starting the materials to react, finishing the reaction of the materials after 5 hours of reaction to form a prepolymer, and closing the reaction kettle to cool the prepolymer to 35 ℃;

s4: and (3) sequentially adding tert-butyl hydroperoxide and oil soluble green into the cooled prepolymer of S3, reacting at 35 ℃ for 40min, cooling the materials in the reaction kettle to room temperature after the reaction is finished, and discharging to obtain the refrigerating pipeline sealant.

The sealant prepared by the embodiment has good adhesive film flexibility, can be repeatedly bent at 180 degrees at-50-180 ℃ without fracture, has the tensile strength of 742N, and can avoid gas leakage under the pressure of 6 MPa.

Example 6

The sealant of the present embodiment comprises the following components by weight percent:

wherein the mean particle size of the polyether-ether-ketone is 20-50 nm.

The preparation method of the sealant of the present embodiment includes the following steps:

s1: accurately weighing the raw materials of each component for later use;

s2: sequentially adding bifunctional aromatic, tetraethylene glycol dimethacrylate, ascorbic acid, gamma-methacryloxy trimethoxy silane, polyether-ether-ketone and p-benzoquinone into a reaction kettle preheated to 50 ℃;

s3: starting the reaction kettle for stirring, controlling the temperature at 50 ℃, starting the materials to react, finishing the reaction of the materials after 4 hours of reaction to form a prepolymer, and closing the reaction kettle to cool the prepolymer to 40 ℃;

s4: and (3) sequentially adding low-odor dicumyl peroxide and oil-soluble blue into the cooled prepolymer of S3, reacting for 40min at 40 ℃, cooling the materials in the reaction kettle to room temperature after the reaction is finished, and discharging to obtain the refrigerating pipeline sealant.

The sealant prepared by the embodiment has good adhesive film flexibility, can be repeatedly bent at 180 degrees at-50-180 ℃ without breaking, has the tensile strength of 711N, and can avoid gas leakage within 6 MPa.

Example 7

wherein the average particle size of the nitrile rubber is 50-70 nm.

s1: accurately weighing the raw materials of each component for later use;

s2: sequentially adding epoxy modified polyurethane oligomer, trimethylpropane methacrylate, tri-n-butylamine, gamma-methacryloxy trimethoxy silane, nitrile rubber and p-hydroxyanisole into a reaction kettle preheated to 55 ℃;

s3: starting the reaction kettle for stirring, controlling the temperature to be 55 ℃, starting the materials to react, finishing the reaction of the materials after 4 hours of reaction to form a prepolymer, and closing the reaction kettle to cool the prepolymer to 40 ℃;

s4: and (3) sequentially adding tert-butyl hydroperoxide and oil-soluble green into the cooled prepolymer of S3, reacting at 40 ℃ for 40min, cooling the materials in the reaction kettle to room temperature after the reaction is finished, and discharging to obtain the refrigerating pipeline sealant.

The sealant prepared by the embodiment has good flexibility of a glue film, can be repeatedly bent at 180 degrees at minus 50-180 ℃ without fracture, has the tensile strength of 673N, and has no gas leakage phenomenon within the air pressure of 8 Mpa.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The low-temperature-resistant refrigerant pipeline sealant is characterized by comprising the following components in percentage by weight:

2. the low temperature resistant refrigerant pipe sealant as set forth in claim 1, which is prepared from the following components in percentage by weight:

3. the low temperature resistant refrigeration pipeline sealant as claimed in claim 1, wherein the nano toughening agent is one or a combination of two or more of nano polyetherimide particles, nano polyetheretherketone particles and nano nitrile rubber particles, and the particle size of the nano toughening agent is 20nm to 100 nm.

4. The low temperature resistant refrigerant pipe sealant as set forth in claim 1, wherein the elastic resin is one or a mixture of two or more of multifunctional aromatic urethane acrylate, difunctional aliphatic urethane acrylate, modified epoxy oligomer, and modified metal ion-treated oligomer.

5. The low temperature resistant refrigerant pipe sealant according to claim 1, wherein the acrylate monomer is one or a mixture of two or more of hydroxypropyl methacrylate, triethylene glycol methacrylate, tetraethylene glycol dimethacrylate, ethoxylated bisphenol a dimethacrylate, and trimethylolpropane trimethacrylate.

6. The low temperature resistant refrigerant pipeline sealant according to claim 1, wherein the accelerator is one or a mixture of two or more of acetophenylhydrazine, o-benzoylsulfonimide, ascorbic acid and tri-n-butylamine.

7. The low temperature resistant refrigerant pipe sealant according to claim 1, wherein the initiator is one or a mixture of two or more of cumene hydroperoxide, tert-butyl hydroperoxide and dicumyl peroxide.

8. The low temperature resistant refrigerant pipe sealing agent of claim 1, wherein the stabilizer is one or a mixture of more than two of hydroquinone, p-hydroxyanisole and p-benzoquinone.

9. The preparation method of the low-temperature-resistant refrigerant pipeline sealant is characterized by comprising the following steps of:

s1: accurately weighing the raw materials of each component for later use;

s3: starting the reaction vessel to stir, controlling the temperature to be 50-55 ℃, starting the materials to react, forming a prepolymer after the reaction is finished, and closing the reaction vessel to cool the prepolymer to be below 40 ℃;

s5: and starting the reaction container again to stir, controlling the temperature to be 35-40 ℃, cooling the material to be below 35 ℃ after the reaction is finished, and discharging to obtain the low-temperature-resistant refrigeration pipeline sealant.

10. Use of the low temperature-resistant refrigerant pipe sealant according to any one of claims 1 to 8 or the low temperature-resistant refrigerant pipe sealant prepared by the preparation method according to claim 9 in a metal pipeline system of a temperature-regulating device.