Adhesive for glass fiber reinforced plastic composite pipe joint and preparation method thereof

Abstract

The invention discloses an adhesive for a glass fiber reinforced plastic composite pipe joint, which is prepared from the following raw materials in parts by mass: 100 parts of epoxy prepolymer, 30-40 parts of polyether amine ketonimine, 8-12 parts of polyurethane prepolymer, 1-3 parts of a curing agent and 1-3 parts of a curing agent. The invention relates to a high-strength and high-wear-resistance cement grinding aid which comprises the following components in parts by weight: 40-45 parts of 800-mesh ground calcium carbonate, 12-16 parts of 80-140-mesh quartz sand, 2-4 parts of fumed silica, 6-10 parts of short glass fibers or short carbon fibers with the specification of 3-5mm, 0.5-1.5 parts of a dispersing agent, 0.5-1 part of aluminum trichloride and 0.5-1 part of an accelerant. The invention further discloses a preparation method of the adhesive for the glass fiber reinforced plastic composite pipe joint, and the problems that in the prior art, an adhesive is long in curing time and low in tensile shear strength are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil and gas pipelines, and particularly relates to an adhesive for a fiberglass composite pipe joint. The present invention also relates to a preparation method of the adhesive. Background Art

[0002] Due to a series of advantages such as excellent corrosion resistance, high strength, smooth inner surface, high wear resistance, anti-aging, and long service life, fiberglass composite pipes have become one of the important non-metallic pipes for solving the corrosion problem of oilfield surface gathering and transportation pipe networks in China. They are now widely used in fields such as oilfield gathering, water injection, and sewage treatment. Fiberglass composite pipes usually have a polypropylene, polyvinyl chloride resin, polyethylene, or other modified thermoplastic resin as the inner layer pipe, and a fiberglass layer formed by continuous glass fibers impregnated with a thermosetting resin as the structural layer. The connection joints of the pipes are usually made of metal, and a high-performance adhesive is used to connect the metal joints and the pipe body into one. With the extension of the service time and the influence of the high-temperature environment of the transported medium, if the adhesive is not properly selected, the problem of composite pipe joint detachment and failure frequently occurs, posing a severe challenge to the safe production and environmental protection of oilfields.

[0003] The main reasons for the failure of the adhesive connection are: first, the poor adhesion between the adhesive and the fiberglass pipe body interface; second, the long curing time of the adhesive; third, the low tensile shear strength of the adhesive, which cannot meet the requirements of the working conditions. Summary of the Invention

[0004] The purpose of the present invention is to provide an adhesive for a fiberglass composite pipe joint, which solves the problems of long curing time and low tensile shear strength existing in the prior art.

[0005] Another purpose of the present invention is to provide a preparation method of the above adhesive.

[0006] The technical solution adopted by the present invention is that the adhesive for a fiberglass composite pipe joint is composed of the following raw materials by mass: 100 parts of epoxy prepolymer, 30 parts - 40 parts of polyetheramine ketone imine, 8 parts - 12 parts of polyurethane prepolymer, 40 parts - 45 parts of 800-mesh heavy calcium carbonate, 12 - 16 parts of 80 - 140-mesh quartz sand, 2 - 4 parts of fumed silica, 6 parts - 10 parts of short glass fibers or short carbon fibers with a specification of 3 - 5 mm, 0.5 parts - 1.5 parts of dispersant, 0.5 parts - 1 part of aluminum trichloride, and 0.5 - 1 part of accelerator.

[0007] The present invention is further characterized in that:

[0008] The epoxy prepolymer is prepared by adding 20 parts by mass of polyetheramine D2000 to 100 parts of bisphenol A epoxy resin E-51 at room temperature and stirring evenly to transparency at 120°C.

[0009] The epoxy equivalent of bisphenol A epoxy resin E-51 is 700-750, and the softening point is 90°C-100°C.

[0010] The molecular structure of polyetheramine ketone imine is shown in Formula 1. Polyetheramine ketone imine uses a strongly acidic ion exchange resin with sulfonic acid groups as a catalyst. 4-Methyl-2-pentanone is heated to 70°C, and then polyetheramine D400 is titrated and added. The molar ratio of polyetheramine D400 to 4-methyl-2-pentanone is 1:2.5. It is refluxed for 1 hour at 120°C. Finally, the water generated in the reactants is separated by distillation, and the remaining light yellow transparent liquid is refined by vacuum distillation to obtain polyetheramine ketone imine.

[0011]

[0012] The polyurethane prepolymer is a polyurethane prepolymer with an active isocyanate group at the end and an activity of 1.

[0013] The accelerator is 2,4,6-tris(dimethylaminomethyl)phenol.

[0014] Another technical solution adopted by the present invention is a preparation method for an adhesive for a fiberglass composite pipe joint, which is specifically implemented according to the following steps:

[0015] Step 1: Weigh 100 parts of epoxy prepolymer, 30-40 parts of polyetheramine ketone imine, 8-12 parts of solid polyurethane prepolymer, 40-45 parts of 800-mesh heavy calcium carbonate, 12-16 parts of 80-140-mesh quartz sand, 2-4 parts of fumed silica, 6-10 parts of 3-5 mm short glass fibers or short carbon fibers, 0.5-1.5 parts of dispersant, 0.5-1 part of aluminum trichloride, and 0.5-1 part of accelerator respectively;

[0016] Step 2: Take the epoxy prepolymer, polyetheramine ketone imine, and polyurethane prepolymer and mix and stir them for 10 minutes;

[0017] Step 3: Take the dispersant, heavy calcium carbonate, quartz sand, and fumed silica, and add them to the mixture prepared in Step 2, and stir for 10 minutes;

[0018] Step 4: Take aluminum trichloride, accelerator, and short glass fibers or short carbon fibers and add them to the mixture prepared in Step 3, and stir for 10 minutes to obtain the adhesive.

[0019] The beneficial effects of the present invention are:

[0020] The glass fiber reinforced plastic composite pipe joint adhesive provided by the present invention belongs to a one-component room temperature curing adhesive. The epoxy resin is internally toughened and modified with polyetheramine D2000, which not only improves the tensile shear strength of the adhesive, but also increases the room temperature curing rate, facilitating construction; the polyurethane prepolymer can react with both the epoxy resin and the amine generated after the ketimine decomposes in the presence of water, thereby forming an interpenetrating network, improving the properties of the epoxy resin cured product, and at the same time accelerating the curing speed of the epoxy resin; the added aluminum trichloride generates hydrochloric acid when it encounters water, which can also accelerate the curing reaction speed. The present invention uses polyetheramine ketimine as a wet state curing agent, in combination with a variety of accelerators and polyurethane prepolymer crosslinking agents. The final adhesive has a short curing time and excellent performance, meeting the predetermined indicators. The present invention can be used as an adhesive for bonding metal joints of glass fiber reinforced plastic composite pipes, and is suitable for connecting pipe joints under harsh and complex working conditions such as the transportation of corrosive media at high temperatures, and has broad application prospects. Specific Embodiments

[0021] The present invention will be described in detail below in conjunction with specific embodiments.

[0022] The adhesive for glass fiber reinforced plastic composite pipe joints provided by the present invention is composed of the following raw materials by mass parts: 100 parts of epoxy prepolymer, 30 parts - 40 parts of polyetheramine ketimine, 8 parts - 12 parts of polyurethane prepolymer, 40 parts - 45 parts of 800-mesh heavy calcium carbonate, 12 parts - 16 parts of 80 - 140-mesh quartz sand, 2 parts - 4 parts of fumed silica, 6 parts - 10 parts of short glass fibers or short carbon fibers with a specification of 3 - 5 mm, 0.5 parts - 1.5 parts of dispersant, 0.5 parts - 1 part of aluminum trichloride, 0.5 parts - 1 part of accelerator, and 1.5 parts - 2.5 parts of water.

[0023] Further, the epoxy prepolymer is prepared by adding 20 parts by mass fraction of D2000 to 100 parts of bisphenol A epoxy resin E-51 at room temperature and stirring evenly to transparency at 120°C.

[0024] Further, the epoxy equivalent of bisphenol A epoxy resin E-51 is 700 - 750, and the softening point is 90°C - 100°C.

[0025] Further, the molecular structure of the polyetheramine ketimine is shown in Formula 1, and its preparation method is: using a sulfonic acid group strongly acidic ion exchange resin as a catalyst, heating 4-methyl-2-pentanone (molecular formula: (CH3)2CHCH2COCH3) to 70°C, and starting to titrate and add polyetheramine D400. The molar ratio of polyetheramine D400 to 4-methyl-2-pentanone is 1:2.5. Reflux for 1 hour at 120°C, and finally distill and separate the water generated in the reactants. The remaining light yellow transparent liquid is refined by vacuum distillation to obtain polyetheramine ketimine.

[0027]

[0028] Further, the polyurethane prepolymer is a polyurethane prepolymer with an isocyanate group at the end group and an activity of 1.

[0029] Further, the accelerator is 2,4,6-tris(dimethylaminomethyl)phenol (abbreviated as DMP-30).

[0030] The present invention also provides a preparation method of the above-mentioned adhesive, including the following steps:

[0031] Step 1: Weigh 100 parts of epoxy prepolymer, 30-40 parts of polyetheramine ketone imine, 8-12 parts of solid polyurethane prepolymer, 40-45 parts of 800-mesh heavy calcium carbonate, 12-16 parts of 80-140-mesh quartz sand, 2-4 parts of fumed silica, 6-10 parts of short glass fibers or short carbon fibers with a length of 3-5 mm, 0.5-1.5 parts of dispersant, 0.5-1 part of aluminum trichloride, and 0.5-1 part of accelerator respectively;

[0032] Step 2: Take the epoxy prepolymer, polyetheramine ketone imine, and polyurethane prepolymer and mix and stir them for 10 minutes;

[0033] Step 3: Take the dispersant, heavy calcium carbonate, quartz sand, and fumed silica, and add them to the mixture prepared in Step 2, and stir for 10 minutes;

[0034] Step 4: Take aluminum trichloride, accelerator, and short glass fibers or short carbon fibers and add them to the mixture prepared in Step 3, and stir for 10 minutes to obtain the adhesive.

[0035] Step 5: Add water in a specified mass ratio before use and stir for 10 minutes.

[0036] Example 1

[0037] The adhesive for fiberglass composite pipe joints provided in this example is composed of the following raw materials by mass: 100 parts of epoxy prepolymer, 30 parts of polyetheramine ketone imine, 8 parts of polyurethane prepolymer, 40 parts of 800-mesh heavy calcium carbonate, 12 parts of 80-mesh quartz sand, 2 parts of fumed silica, 6 parts of short carbon fibers with a specification of 3 mm, 0.5 part of dispersant, 0.5 part of aluminum trichloride, 0.5 part of accelerator, and 1.5 parts of water; the epoxy prepolymer is prepared by adding 20 parts by mass of polyetheramine D2000 to 100 parts of bisphenol A epoxy resin E-51 at room temperature and stirring evenly to be transparent at 120°C; the epoxy equivalent of bisphenol A epoxy resin E-51 is 700-750, and the softening point is 90°C-100°C;

[0038] Example 2

[0039] The present embodiment provides an adhesive for glass fiber reinforced plastic composite pipe joints, which is composed of the following raw materials in parts by mass: 100 parts of epoxy prepolymer, 30 parts of polyetheramine ketimine, 8 parts of polyurethane prepolymer, 43 parts of 800-mesh heavy calcium carbonate, 14 parts of 100-mesh quartz sand, 3 parts of fumed silica, 8 parts of 4mm short glass fibers, 0.8 parts of dispersant, 0.8 parts of aluminum chloride, 0.8 parts of accelerator, and 2 parts of water; the epoxy prepolymer is prepared by adding 20 parts of polyetheramine D2000 by mass to 100 parts of bisphenol A epoxy resin E-51 at room temperature and stirring at 120°C until transparent; the bisphenol A epoxy resin The epoxy equivalent of resin E-51 is 700-750, and the softening point is 90°C-100°C; the molecular structure of polyetheramine ketone imine is shown in Formula 1, and polyetheramine ketone imine uses sulfonic acid strong acid ion exchange resin as a catalyst, 4-methyl-2-pentanone is heated to 70°C, polyetheramine D400 is titrated, the molar ratio of polyetheramine D400 to 4-methyl-2-pentanone is 1:2.5, reflux at 120°C for 1 hour, and finally distill and separate the water generated in the reactants, and the remaining light yellow transparent liquid is subjected to vacuum distillation and purification to obtain polyetheramine ketone imine; the polyurethane prepolymer is a polyurethane prepolymer with a terminal isocyanate activity of 1;

[0040]

[0041] Example 3

[0042] The present embodiment provides an adhesive for glass fiber reinforced plastic composite pipe joints, which is composed of the following raw materials in parts by mass: 100 parts of epoxy prepolymer, 40 parts of polyetheramine ketimine, 12 parts of polyurethane prepolymer, 45 parts of 800-mesh heavy calcium carbonate, 16 parts of 140-mesh quartz sand, 4 parts of fumed silica, 10 parts of 5 mm short glass fibers, 1.5 parts of dispersant, 1 part of aluminum chloride, 1 part of accelerator, and 2.5 parts of water; the epoxy prepolymer is prepared by adding 20 parts of polyetheramine D2000 by mass to 100 parts of bisphenol A epoxy resin E-51 at room temperature and stirring at 120° C. until transparent; the epoxy equivalent of bisphenol A epoxy resin E-51 is 7 00~750, the softening point is 90℃~100℃; the molecular structure of polyetheramine ketimine is shown in Formula 1, polyetheramine ketimine uses sulfonic acid strong acid ion exchange resin as catalyst, 4-methyl-2-pentanone is heated to 70℃, polyetheramine D400 is added titratingly, the molar ratio of polyetheramine D400 to 4-methyl-2-pentanone is 1:2.5, refluxed at 120℃ for 1 hour, and finally the water generated in the reactant is separated by distillation, and the remaining light yellow transparent liquid is subjected to vacuum distillation and refined to obtain polyetheramine ketimine; the polyurethane prepolymer is a polyurethane ester prepolymer with a terminal isocyanate activity of 1; the accelerator is 2,4,6-tris(dimethylaminomethyl)phenol.

[0043]

[0044] Example 4

[0045] This example provides a preparation method for the adhesive of fiberglass composite pipe joints, and the specific steps are as follows:

[0046] Step 1: Weigh 100 parts of epoxy prepolymer, 30 - 40 parts of polyetheramine ketimine, 8 - 12 parts of solid polyurethane prepolymer, 40 - 45 parts of 800 - mesh heavy calcium carbonate, 12 - 16 parts of 80 - 140 - mesh quartz sand, 2 - 4 parts of fumed silica, 6 - 10 parts of 3 - 5 mm short glass fibers or short carbon fibers, 0.5 - 1.5 parts of dispersant, 0.5 - 1 part of aluminum trichloride, and 0.5 - 1 part of accelerator respectively;

[0047] Step 2: Take the epoxy prepolymer, polyetheramine ketimine, and polyurethane prepolymer, and mix and stir them for 10 minutes;

[0048] Step 3: Take the dispersant, heavy calcium carbonate, quartz sand, and fumed silica, and add them to the mixture obtained in Step 2, and stir for 10 minutes;

[0049] Step 4: Take aluminum trichloride, accelerator, and short glass fibers or short carbon fibers and add them to the mixture obtained in Step 3, and stir for 10 minutes to obtain the adhesive.

[0050] Step 5: Add water in a specified mass ratio before use and stir for 10 minutes.

[0051] Test Example 1

[0052] Use the adhesives prepared with the formulations of Example 1, Example 2, and Example 3 to conduct the curing speed test and the performance test of the cast body. The test results are shown in Table 1:

[0053] Table 1 Performance of the cured product of the adhesive

[0054]

[0055] Test Example 2

[0056] Use the adhesives prepared with the formulations of Example 1, Example 2, and Example 3 to verify the bonding of metal joints to fiberglass composite pipes. The pipe body of the composite pipe used is a DN100mm / PN20MPa polypropylene - lined fiberglass composite pipe, and the metal joint material is high - quality carbon structural steel. The pipe body and the metal joint comply with the standard SY / T6662.7 - 2016.

[0057] Randomly select 6 glass composite pipes from the same batch that meet the product quality requirements, and make short sections with a free length of 1000 mm between two sealed joints. One end of the specimen is sealed, and the other end has a metal hole through which clear water can be injected. Place the specimen in a constant temperature water bath with temperature control for conditioning. Adjust the water bath to 65°C ± 2°C before putting the specimen in. The specimen is placed in the constant temperature water bath for 12 h ± 0.1 h.

[0058] Connect the specimen after conditioning to the pressure equipment for a burst test, and the method is in accordance with GB / T5351. The test results are shown in Table 2:

[0059] Table 2 Burst test results of fiberglass reinforced plastic composite pipe specimens

[0060] Specimen number Burst strength value, MPa Failure time, s Failure morphology 1 102.6 50 Burst in the middle of the pipe body 2 100.5 56 3 109.2 54 Burst in the middle of the pipe body 4 107.5 55 5 108.6 52 Burst in the middle of the pipe body 6 108.8 54

Claims

1. An adhesive for a glass fiber reinforced plastic composite pipe joint, characterized in that, it is composed of the following raw materials by mass parts: 100 parts of epoxy prepolymer, 30 parts - 40 parts of polyetheramine ketimine, 8 parts - 12 parts of polyurethane prepolymer, 40 parts - 45 parts of 800 - mesh heavy calcium carbonate, 12 parts - 16 parts of 80 - 140 - mesh quartz sand, 2 parts - 4 parts of fumed silica, 6 parts - 10 parts of short glass fibers or short carbon fibers with a specification of 3mm - 5mm, 0.5 parts - 1.5 parts of dispersant, 0.5 parts - 1 part of aluminum trichloride, and 0.5 parts - 1 part of accelerator.

2. The adhesive for a glass fiber reinforced plastic composite pipe joint according to claim 1, characterized in that, the epoxy prepolymer is prepared by adding 20 parts by mass of polyetheramine D2000 to 100 parts of bisphenol A epoxy resin E - 51 at room temperature, mixing, and stirring evenly to a transparent state at 120°C.

3. The adhesive for a glass fiber reinforced plastic composite pipe joint according to claim 2, characterized in that, the epoxy equivalent of the bisphenol A epoxy resin E - 51 is 700 - 750, and the softening point is 90°C - 100°C.

4. The adhesive for a glass fiber reinforced plastic composite pipe joint according to claim 1, characterized in that, the molecular structure of the polyetheramine ketimine is shown in Formula 1. The polyetheramine ketimine uses a sulfonic acid - based strongly acidic ion - exchange resin as a catalyst. Heat 4 - methyl - 2 - pentanone to 70°C, and start titrating and adding polyetheramine D400. The molar ratio of polyetheramine D400 to 4 - methyl - 2 - pentanone is 1:2.

5. Reflux at 120°C for 1 hour. Finally, distill and separate the water generated in the reactants, and carry out vacuum distillation and refining on the remaining light yellow transparent liquid to obtain polyetheramine ketimine.

5. The adhesive for a glass fiber reinforced plastic composite pipe joint according to claim 1, characterized in that, the polyurethane prepolymer is a polyurethane prepolymer with a terminal isocyanate group activity of 1.

6. The adhesive for a glass fiber reinforced plastic composite pipe joint according to claim 1, characterized in that, the accelerator is 2,4,6 - tris(dimethylaminomethyl)phenol.

7. The preparation method of the adhesive for a glass fiber reinforced plastic composite pipe joint according to any one of claims 1 - 6, characterized in that, It includes the following steps: Step 1: Weigh 100 parts of epoxy prepolymer, 30 - 40 parts of polyetheramine ketone imine, 8 - 12 parts of solid polyurethane prepolymer, 40 - 45 parts of 800 - mesh heavy calcium carbonate, 12 - 16 parts of 80 - 140 - mesh quartz sand, 2 - 4 parts of fumed silica, 6 - 10 parts of 3 - 5 - mm short glass fibers or short carbon fibers, 0.5 - 1.5 parts of dispersant, 0.5 - 1 part of aluminum trichloride, and 0.5 - 1 part of accelerator respectively; Step 2: Take the epoxy prepolymer, polyetheramine ketone imine, and polyurethane prepolymer, mix and stir for 10 minutes; Step 3: Take the dispersant, heavy calcium carbonate, quartz sand, and fumed silica, and add them to the mixture obtained in Step 2, and stir for 10 minutes; Step 4: Take the aluminum trichloride, accelerator, and short glass fibers or short carbon fibers and add them to the mixture obtained in Step 3, and stir for 10 minutes to obtain the adhesive.

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