Gap filling glue for wall and preparation process

Abstract

The invention relates to the technical field of caulking adhesives, and discloses a caulking adhesive for a wall body and a preparation technology, the caulking adhesive for the wall body comprises a component A, a component B, a component C and a component D, and the component B comprises the following components in parts by weight: 130-145 parts of polyether polyol, 30-50 parts of filler, 10-40 parts of functional cellulose aerogel and the like. The functional cellulose aerogel contains a large number of carbamic acid ester groups, has good compatibility with the polyurethane joint sealant, has strong interaction force such as hydrogen bonds and the like between the functional cellulose aerogel and the polyurethane joint sealant, has little influence on the mechanical properties of the polyurethane joint sealant, and is uniformly distributed in the joint sealant, so that the mechanical properties of the polyurethane joint sealant are greatly improved. The heat conductivity coefficient of the caulking glue can be obviously reduced, and the thermal insulation performance is improved. The functional cellulose aerogel contains a large number of biquaternary ammonium salt groups, so that the caulking glue shows good mildew resistance grade and mildew resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of caulking adhesives, and specifically to a caulking adhesive for walls and a preparation process thereof. Background Art

[0002] Polyurethane caulking adhesives have good adhesion, sealing, waterproofing and plugging properties, and are widely used in wall caulking repair. Chemical modification of polyurethane caulking adhesives to improve their heat insulation, mildew resistance and other properties is a research hotspot. Cellulose aerogel is a porous gel material with low thermal conductivity and excellent heat insulation performance, and has broad application prospects in products such as adhesives, coatings, and plastics. Chinese Patent CN116640546B discloses a heat-insulating and antibacterial polyurethane adhesive material and its preparation method, which chemically crosslinks cellulose with aspartic acid, and then reacts with aspartic acid, tris(2-aminoethyl)amine, and benzyl bromide, and freeze-dries to obtain hyperbranched quaternary ammonium salt-modified cellulose aerogel, improving the antibacterial and heat insulation properties of the polyurethane adhesive. However, the raw materials of the modified cellulose aerogel in this patent are relatively complex and the preparation method is complicated, which is not conducive to industrial actual production. Summary of the Invention

[0003] The present invention solves the problems of poor mildew resistance and heat insulation performance of polyurethane caulking adhesives.

[0004] The technical solution of the present invention: A caulking adhesive for walls and a preparation process thereof. The caulking adhesive for walls includes component A and component B; Component A includes 100 parts by weight of polyurethane prepolymer; Component B includes 130-145 parts by weight of polyether polyol, 30-50 parts by weight of filler, 0.02-0.05 parts by weight of dibutyltin dilaurate, 7-10 parts by weight of plasticizer, 10-40 parts by weight of functional cellulose aerogel.

[0005] The preparation process of the caulking adhesive for walls is as follows: Grind and mix polyether polyol, filler, plasticizer, and functional cellulose aerogel, then add dibutyltin dilaurate and stir evenly to obtain component B; Mix component B with the polyurethane prepolymer of component A to obtain the caulking adhesive for walls.

[0006] Preferably, the filler is any one or a combination of calcium carbonate, bentonite or talcum powder.

[0007] Preferably, the plasticizer is dioctyl phthalate.

[0008] Preferably, the preparation process of the polyurethane prepolymer is as follows: React polyether polyol and diisocyanate monomer with a molar ratio of 1:(2.6-3) in a nitrogen atmosphere at 70-80°C for 2-3 hours, cool and discharge to obtain the polyurethane prepolymer.

[0009] Preferably, the diisocyanate monomer is isophorone diisocyanate, 4,4'-methylenebis(phenyl isocyanate) or toluene-2,4-diisocyanate.

[0010] Preferably, the preparation process of the functional cellulose aerogel is as follows:

[0011] (1) Add N,N-dimethylethanolamine, isophorone diisocyanate, and dibutyltin dilaurate to tetrahydrofuran, and carry out a condensation reflux reaction at 60-65 °C for 6-7 h to generate an isophorone diisocyanate semi-addition intermediate; then add dibromoalkane and acetonitrile co-solvent, and carry out a condensation reflux reaction at 80-85 °C for 24-30 h. Heat and volatilize in a fume hood, cool and crystallize to obtain bisquaternary ammonium salt diisocyanate. The reaction formula is as follows:

[0012]

[0013] (2) Add microcrystalline cellulose to N,N-dimethylacetamide, stir and activate at 130-140 °C for 1-2 h, then add lithium chloride, stir and dissolve at 100-110 °C for 2-3 h, add bisquaternary ammonium salt diisocyanate and dibutyltin dilaurate, and carry out a stirring reaction at 65-80 °C for 2-4 h. Add deionized water to the solution, filter and wash with ethanol and deionized water; soak the gel product in deionized water, filter and freeze-dry to obtain the functional cellulose aerogel.

[0014] Preferably, in (1), the molar ratio of N,N-dimethylethanolamine, isophorone diisocyanate, dibutyltin dilaurate, and dibromoalkane is 1:(1.08-1.1):(0.03-0.04):(0.4-0.45).

[0015] Preferably, the structural formula of the dibromoalkane in (1) is n is 10-16.

[0016] Preferably, in (2), the mass ratio of microcrystalline cellulose, quaternary ammonium salt diisocyanate, and dibutyltin dilaurate is 100:(10-35):(0.006-0.026).

[0017] The beneficial technical effects of the present invention: In the present invention, N,N-dimethylethanolamine, isophorone diisocyanate, and dibromoalkane are reacted to obtain bisquaternary ammonium salt diisocyanate, and then the active isocyanate group is reacted with the hydroxyl group of microcrystalline cellulose to obtain a cellulose gel product, which is freeze-dried to obtain a functional cellulose aerogel containing urethane groups and bisquaternary ammonium salt structures.

[0018] In the present invention, polyether polyol, filler, functional cellulose aerogel, etc. are used as component B of the polyurethane sealant, and the polyurethane prepolymer is used as component A of the sealant. The functional cellulose aerogel contains a large number of urethane groups identical to those of the polyurethane sealant, so that there is good compatibility between the functional cellulose aerogel and the polyurethane sealant, and there are strong intermolecular forces such as hydrogen bonds between the two. The functional cellulose aerogel can be evenly distributed in the sealant matrix, with little impact on the mechanical properties of the polyurethane sealant, so that the cured sealant maintains good tensile strength and elongation at break. Moreover, the functional cellulose aerogel is evenly distributed in the sealant, which can significantly reduce the thermal conductivity of the sealant, thereby improving the thermal insulation performance.

[0019] The functional cellulose aerogel of the present invention contains a large number of bisquaternary ammonium salt groups, which can destroy the cell membrane structure of microorganisms such as bacteria and molds, effectively kill bacteria and molds, and thus exhibit good mildew resistance grade and mildew-proof performance. It has good practical applications in the repair, thermal insulation and mildew prevention of walls. Specific embodiments

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0021] The following polyether polyol has the model N220 and an average molecular weight of 2000. Microcrystalline cellulose has a CAS registration number of 9004-34-6.

[0022] Example 1:

[0023] (1) Add 10 mmol of N,N-dimethylethanolamine, 11 mmol of isophorone diisocyanate, and 0.3 mmol of dibutyltin dilaurate to 20 mL of tetrahydrofuran, and carry out a condensation reflux reaction at 65 °C for 6 h to generate an isophorone diisocyanate semi-addition intermediate; then add 4 mmol of 1,12-dibromododecane and 25 mL of acetonitrile cosolvent, and carry out a condensation reflux reaction at 80 °C for 30 h. Heat and volatilize in a fume hood, cool and crystallize to obtain bisquaternary ammonium salt diisocyanate.

[0024] (2) Add 50 g of microcrystalline cellulose to 2 L of N,N-dimethylacetamide, stir and activate it at 140 °C for 1 h, then add 170 g of lithium chloride, stir and dissolve it at 100 °C for 3 h, add 5 g of bisquaternary ammonium diisocyanate, 3 mg of dibutyltin dilaurate, stir and react at 80 °C for 2 h, add deionized water to the solution, filter and wash with ethanol and deionized water; Immerse the gel product in 3 L of deionized water for 6 h, and freeze-dry it in a freeze dryer for 48 h to obtain the functional cellulose aerogel.

[0025] (3) Mix 100 mmol of dry polyether polyol and 280 mmol of isophorone diisocyanate, react at 70 °C for 3 h in a nitrogen atmosphere, cool and discharge to obtain the polyurethane prepolymer.

[0026] (4) Grind and mix 1 kg of polyether polyol, 0.3 kg of filler calcium carbonate, 0.12 kg of bentonite, 80 g of plasticizer dioctyl phthalate, and 100 g of functional cellulose aerogel, then add 0.3 g of dibutyltin dilaurate and stir evenly to obtain Component B; Mix Component B with 1.36 kg of polyurethane prepolymer of Component A to obtain the caulking sealant for walls.

[0027] Comparative Example 1:

[0028] (1) Grind and mix 1 kg of polyether polyol, 0.3 kg of filler calcium carbonate, 0.12 kg of bentonite, and 80 g of plasticizer dioctyl phthalate, then add 0.3 g of dibutyltin dilaurate and stir evenly to obtain Component B; Mix Component B with 1.36 kg of polyurethane prepolymer of Component A to obtain the caulking sealant for walls.

[0029] Comparative Example 2

[0030] (1) Add 50 g of microcrystalline cellulose to 1.2 L of deionized water, disperse it by high-speed shearing at a rotation speed of 2000 r / min, and freeze-dry it in a freeze dryer for 48 h to obtain cellulose aerogel.

[0031] (2) Grind and mix 1 kg of polyether polyol, 0.3 kg of filler calcium carbonate, 0.12 kg of bentonite, 80 g of plasticizer dioctyl phthalate, and 100 g of cellulose aerogel, then add 0.3 g of dibutyltin dilaurate and stir evenly to obtain Component B; Mix Component B with 1.36 kg of polyurethane prepolymer of Component A to obtain the caulking sealant for walls.

[0032] Comparative Example 3

[0033] (1) Add 50 g of microcrystalline cellulose to 2 L of N,N-dimethylacetamide, stir and activate at 140 °C for 1 h, then add 170 g of lithium chloride, stir and dissolve at 100 °C for 3 h, add 5 g of isophorone diisocyanate and 3 mg of dibutyltin dilaurate, stir and react at 80 °C for 2 h, add deionized water to the solution, filter and wash with ethanol and deionized water; Immerse the gel product in 3 L of deionized water for 6 h, and freeze-dry in a freeze dryer for 48 h to obtain a functional cellulose aerogel.

[0034] (2) Mix 100 mmol of dry polyether polyol and 280 mmol of isophorone diisocyanate, react at 70 °C for 3 h in a nitrogen atmosphere, cool and discharge to obtain a polyurethane prepolymer.

[0035] (3) Grind and mix 1 kg of polyether polyol, 0.3 kg of filler calcium carbonate, 0.12 kg of bentonite, 80 g of plasticizer dioctyl phthalate, and 100 g of functional cellulose aerogel, then add 0.3 g of dibutyltin dilaurate and stir evenly to obtain Component B; Mix Component B with 1.36 kg of polyurethane prepolymer of Component A to obtain a caulking sealant for walls.

[0036] Comparative Example 4

[0037] (1) Add 50 g of microcrystalline cellulose, 0.75 g of potassium hydroxide to 640 mL of isopropanol and 160 mL of deionized water, stir at 60 °C for 1 h, then add 5 g of glycidyl dimethyldodecylammonium chloride (structural formula is ), stir at 65 °C for 4 h, add acetone for precipitation, add glacial acetic acid to neutralize the pH to 7, filter and wash with 90% by volume ethanol aqueous solution to obtain quaternary ammonium salt cellulose; Then immerse the quaternary ammonium salt cellulose in 3 L of deionized water for 6 h, and freeze-dry in a freeze dryer for 48 h to obtain a functional cellulose aerogel.

[0038] (2) Grind and mix 1 kg of polyether polyol, 0.3 kg of filler calcium carbonate, 0.12 kg of bentonite, 80 g of plasticizer dioctyl phthalate, and 100 g of functional cellulose aerogel, then add 0.3 g of dibutyltin dilaurate and stir evenly to obtain Component B; Mix Component B with 1.36 kg of polyurethane prepolymer of Component A to obtain a caulking sealant for walls.

[0039] Example 2:

[0040] (1) 10 mmol of N,N-dimethylethanolamine, 10.8 mmol of isophorone diisocyanate, and 0.4 mmol of dibutyltin dilaurate were added to 20 mL of tetrahydrofuran, and the mixture was refluxed with condensation at 60 °C for 7 h to form an isophorone diisocyanate semi-addition intermediate; then 4.5 mmol of 1,16-dibromohexadecane and 30 mL of acetonitrile as a co-solvent were added, and the mixture was refluxed with condensation at 85 °C for 24 h. After heating and volatilizing in a fume hood and cooling for crystallization, a bisquaternary ammonium salt diisocyanate was obtained.

[0041] (2) 50 g of microcrystalline cellulose was added to 2.5 L of N,N-dimethylacetamide and stirred for activation at 140 °C for 1 h. Then 200 g of lithium chloride was added and dissolved by stirring at 100 °C for 3 h. 9 g of bisquaternary ammonium salt diisocyanate and 6 mg of dibutyltin dilaurate were added, and the mixture was stirred and reacted at 70 °C for 3 h. Deionized water was added to the solution, and after filtration, it was washed with ethanol and deionized water; the gel product was added to 3 L of deionized water and soaked for 6 h, and then freeze-dried in a freeze dryer for 48 h to obtain a functional cellulose aerogel.

[0042] (3) 100 mmol of dry polyether polyol and 300 mmol of toluene-2,4-diisocyanate were mixed and reacted at 70 °C for 3 h in a nitrogen atmosphere, and then cooled and discharged to obtain a polyurethane prepolymer.

[0043] (4) 1 kg of polyether polyol, 0.2 kg of filler calcium carbonate, 0.1 kg of talc powder, 80 g of plasticizer dioctyl phthalate, and 200 g of functional cellulose aerogel were ground and mixed, and then 0.2 g of dibutyltin dilaurate was added and stirred evenly to obtain component B; component B was mixed evenly with 1.3 kg of component A polyurethane prepolymer to obtain a caulking sealant for walls.

[0044] Example 3:

[0045] (1) 50 g of microcrystalline cellulose was added to 2.5 L of N,N-dimethylacetamide and stirred for activation at 130 °C for 2 h. Then 200 g of lithium chloride was added and dissolved by stirring at 100 °C for 3 h. 13 g of bisquaternary ammonium salt diisocyanate (prepared in Example 1), and 10 mg of dibutyltin dilaurate were added, and the mixture was stirred and reacted at 65 °C for 4 h. Deionized water was added to the solution, and after filtration, it was washed with ethanol and deionized water; the gel product was added to 3 L of deionized water and soaked for 6 h, and then freeze-dried in a freeze dryer for 48 h to obtain a functional cellulose aerogel.

[0046] (2) 100 mmol of dry polyether polyol and 280 mmol of isophorone diisocyanate were mixed and reacted at 80 °C for 2 h in a nitrogen atmosphere, and then cooled and discharged to obtain a polyurethane prepolymer.

[0047] (3) Grind and mix 1 kg of polyether polyol, 0.36 kg of filler calcium carbonate, 0.14 kg of talc powder, 100 g of plasticizer dioctyl phthalate, and 300 g of functional cellulose aerogel, then add 0.5 g of dibutyltin dilaurate and stir evenly to obtain Component B; mix Component B with 1.3 kg of polyurethane prepolymer of Component A to obtain the caulking sealant for walls.

[0048] Example 4:

[0049] (1) Add 50 g of microcrystalline cellulose to 2.5 L of N,N-dimethylacetamide, stir and activate at 140 °C for 1 h, then add 200 g of lithium chloride, stir and dissolve at 110 °C for 2 h, add 17.5 g of bisquaternary ammonium diisocyanate (prepared in Example 1), 13 mg of dibutyltin dilaurate, and stir and react at 70 °C for 4 h. Add deionized water to the solution, filter and wash with ethanol and deionized water; soak the gel product in 3 L of deionized water for 6 h and freeze-dry in a freeze dryer for 48 h to obtain the functional cellulose aerogel.

[0050] (2) Mix 100 mmol of dry polyether polyol and 260 mmol of 4,4'-methylenebis(phenyl isocyanate), react at 75 °C for 3 h in a nitrogen atmosphere, cool and discharge to obtain the polyurethane prepolymer.

[0051] (3) Grind and mix 1 kg of polyether polyol, 0.25 kg of filler calcium carbonate, 0.12 kg of talc powder, 70 g of plasticizer dioctyl phthalate, and 400 g of functional cellulose aerogel, then add 0.3 g of dibutyltin dilaurate and stir evenly to obtain Component B; mix Component B with 1.45 kg of polyurethane prepolymer of Component A to obtain the caulking sealant for walls.

[0052] Pour the caulking sealant into a mold and cure at room temperature for 7 days to make a cured specimen. Test the thermal conductivity of the cured specimen of the caulking sealant according to the method specified in the GB / T3399-1982 standard.

[0053] Test the mildew resistance of the cured specimen of the caulking sealant according to the method specified in the GB / T 13477.25-2024 standard. Test the tensile strength according to the method specified in the GB / T 13477.8-2017 standard.

[0054] Table 1 Performance Test of Caulking Sealant

[0055]

[0056] After testing, compared with the sealant of Comparative Example 1, the sealant of Example 1 is added with functional cellulose aerogel, which contains a large number of urethane groups the same as those in the polyurethane sealant, so that there is good compatibility between the functional cellulose aerogel and the polyurethane sealant, and there are strong intermolecular forces such as hydrogen bonds between them. The functional cellulose aerogel can be evenly distributed in the sealant matrix, with little impact on the mechanical properties of the polyurethane sealant, so that the cured sealant maintains good tensile strength and elongation at break. At the same time, the functional cellulose aerogel is evenly distributed in the sealant, which can significantly reduce the thermal conductivity of the sealant, thereby improving the heat insulation performance. And the functional cellulose aerogel contains a large number of bisquaternary ammonium salt groups, which can destroy the cell membrane structure of microorganisms such as bacteria and molds, effectively kill bacteria and molds, and thus show good mildew resistance grade and mildew-proof performance. Examples 2-4 are added with different amounts of functional cellulose aerogel, and the polyurethane sealant also has good heat insulation and mildew-proof performance, and good tensile strength and elongation at break.

[0057] Compared with Example 1, Comparative Example 2 is added with ordinary cellulose aerogel, which does not contain urethane groups, has poor compatibility with the polyurethane sealant, has a greater impact on the mechanical properties of the sealant, and the decline in tensile strength and elongation at break is relatively large. Moreover, the dispersion of the aerogel in the sealant matrix is not good, and it does not effectively reduce the thermal conductivity of the sealant, resulting in poor heat insulation performance. And the cellulose does not contain bisquaternary ammonium salt groups, and the mildew resistance grade of the sealant is 3, with poor mildew-proof performance. In Comparative Example 3, the hydroxyl group of microcrystalline cellulose reacts with isophorone diisocyanate and then freeze-dried to form aerogel, which contains a large number of urethane groups the same as those in the polyurethane sealant, with good compatibility between the two, excellent dispersion of the aerogel, low thermal conductivity of the sealant, good heat insulation performance, and maintaining high tensile strength and elongation at break. However, this functional cellulose aerogel does not contain bisquaternary ammonium salt groups, and the mildew resistance grade of the sealant is 3, with poor mildew-proof performance. In Comparative Example 4, the hydroxyl group of cellulose reacts with the epoxy group of glycidyl dimethyldodecylammonium chloride to obtain quaternary ammonium salt cellulose, and then freeze-dried to obtain functional cellulose aerogel, which does not contain urethane groups, has poor compatibility with the polyurethane sealant, poor dispersion, low tensile strength and elongation at break of the sealant, and a large thermal conductivity, resulting in poor heat insulation performance. And glycidyl dimethyldodecylammonium chloride contains only one quaternary ammonium salt group, while the bisquaternary ammonium diisocyanate in Example 1 contains bisquaternary ammonium salt groups, with better mildew-proof performance, mildew resistance grade of 1, while the mildew resistance grade of Comparative Example 4 is only 2, with poor mildew-proof performance.

[0058] The above content is only an example and illustration of the concept of the present invention. Those skilled in the art of the present technology can make various modifications, supplements, or use similar methods to replace the described specific embodiments, as long as they do not deviate from the concept of the invention or exceed the scope defined by this claim book, they shall fall within the protection scope of the present invention.

Claims

1. A wall sealant, characterized in that: The wall sealant comprises component A and component B; component A comprises 100 parts by weight of polyurethane prepolymer; component B comprises 130-145 parts by weight of polyether polyol, 30-50 parts by weight of filler, 0.02-0.05 parts by weight of dibutyltin dilaurate, 7-10 parts by weight of plasticizer, and 10-40 parts by weight of functional cellulose aerogel; The preparation process of the functional cellulose aerogel is as follows: adding microcrystalline cellulose to N,N-dimethylacetamide, stirring and activating, adding lithium chloride, stirring and dissolving, adding diquaternary ammonium diisocyanate and dibutyltin dilaurate, stirring and reacting, adding deionized water to the solution, filtering and washing; adding the gel product to deionized water for soaking, filtering and freeze-drying, and obtaining the functional cellulose aerogel; The structural formula of the diquaternary ammonium salt diisocyanate is as follows: n is 12-16.

2. The wall sealant according to claim 1, characterized in that: In the preparation process of the functional cellulose aerogel, the mass ratio of microcrystalline cellulose, quaternary ammonium diisocyanate, and dibutyltin dilaurate is 100:(10-35):(0.006-0.026).

3. The wall sealant according to claim 1, characterized in that: The temperature during the stirring activation is 130-140°C and the time is 1-2h; the temperature during the stirring dissolution is 100-110°C and the time is 2-3h; the temperature during the stirring reaction is 65-80°C and the time is 2-4h.

4. The wall sealant according to claim 1, characterized in that: The filler is any one or a combination of calcium carbonate, bentonite or talcum powder; the plasticizer is dioctyl phthalate.

5. The wall sealant according to claim 1, characterized in that: The preparation process of the polyurethane prepolymer is as follows: reacting polyether polyol and diisocyanate monomer in a molar ratio of 1:(2.6-3) in a nitrogen atmosphere at 70-80° C. for 2-3 hours, cooling and discharging the material to obtain the polyurethane prepolymer.

6. The wall sealant according to claim 5, characterized in that: The diisocyanate monomer is isophorone diisocyanate, 4,4'-methylenebis(phenyl isocyanate) or toluene-2,4-diisocyanate.

7. The wall sealant according to claim 1, characterized in that: The preparation process of the diquaternary ammonium salt diisocyanate is as follows: N, N-dimethylethanolamine, isophorone diisocyanate and dibutyltin dilaurate are added to tetrahydrofuran, and the mixture is subjected to condensation reflux reaction at 60-65° C. for 6-7 hours, and then dibromoalkane and acetonitrile as a cosolvent are added, and the mixture is subjected to condensation reflux reaction at 80-85° C. for 24-30 hours, and the mixture is heated for volatilization and cooled for crystallization to obtain the diquaternary ammonium salt diisocyanate.

8. The wall sealant according to claim 7, characterized in that: In the preparation process of the diquaternary ammonium salt diisocyanate, the molar ratio of N,N-dimethylethanolamine, isophorone diisocyanate, dibutyltin dilaurate and dibromoalkane is 1:(1.08-1.1):(0.03-0.04):(0.4-0.45).

9. The wall sealant according to claim 8, characterized in that: The structural formula of the dibromoalkane is n is 10-16.

10. A process for preparing the wall sealant according to any one of claims 1 to 9, characterized in that: The preparation process comprises: grinding and mixing polyether polyol, filler, plasticizer and functional cellulose aerogel, then adding dibutyltin dilaurate, stirring and mixing to obtain component B; and mixing component B and component A polyurethane prepolymer to obtain wall caulking glue.

Images