CN110760264A - A kind of asphalt polyurethane waterproof coating suitable for cement base and its preparation method and application - Google Patents

Abstract

The invention discloses an asphalt polyurethane waterproof coating suitable for a cement base layer and a preparation method and application thereof, wherein the raw materials comprise asphalt, a compatilizer, a water removing agent, a catalyst, a filler and an end-capped polyurethane prepolymer,the end-capped polyurethane prepolymer is prepared by reacting a compound shown as a formula (I) with a polyurethane prepolymer, and the end-capped polyurethane prepolymer does not contain an end isocyanate group; preparation: preparing an end-capped polyurethane prepolymer, and mixing the end-capped polyurethane prepolymer with the rest raw materials; and the application of the waterproof coating on the asphalt waterproof coiled material constructed on the cement base layer; the waterproof coating disclosed by the invention is safe in preparation process, can be directly coated on a cement base layer with more water content during use, can react with silicate in cement after hydrolysis, improves the bonding force on a wet base layer, has excellent bonding strength with an asphalt waterproof coiled material, particularly has relatively fast surface drying and drying time and moderate viscosity (the step of heating before construction can be basically avoided), and is beneficial to field construction.

Description

A kind of asphalt polyurethane waterproof coating suitable for cement base and preparation method thereof application

technical field

The invention belongs to the field of building waterproofing, and particularly relates to a bituminous polyurethane waterproofing coating suitable for cement base layers and a preparation method and application thereof.

Background technique

At present, waterproofing membranes have been greatly promoted and used in construction applications. They are mainly used in building walls, roofs, tunnels, highways, etc., to resist external rainwater and groundwater leakage. Rolled flexible building materials, as a non-leakage connection between the engineering foundation and the building, are the first waterproof barrier for the entire project and play a vital role in the entire project. Quality acceptance specification) and design regulations and other requirements for construction. Among them, the base layer (currently basically a cement base layer) should have a certain strength, and should not be shelled, loose, uneven, and the dust and foreign matter on the roof and sub-silo joints must be removed; the base layer should be dry, with a moisture content of less than 8%, etc. Generally, the base layer is whitish without obvious water marks, or a piece of 1m×1m linoleum is laid flat on a clean flat surface for 3-4 hours. If the color of the base layer covered with linoleum is still the same as the surrounding uncovered parts, and there is no obvious watermark, it means water rate has been met. However, in the construction process, especially in the rainy days and other periods of rapid weather changes and humid air, based on the above-mentioned waterproofing membrane construction and the construction effect is good, it is necessary to strictly control the moisture content of the cement base, which will affect the progress of the project. The obvious impact is not conducive to shortening the construction period and reducing the construction cost.

In the prior art, the waterproofing membrane products mainly include bitumen waterproofing membrane and polymer waterproofing membrane, among which the application range of the bituminous waterproofing membrane is still very wide, but there is still a need for the cement base layer to be applied to the cement base layer. The pretreatment step includes the control of impurities and moisture content. Impurities are easier to clean, but the moisture content is difficult to control in real time and accurately, especially in the rainy days and other periods when the weather changes rapidly and the air is humid. The adhesion with the cement base needs to be improved.

In view of the above-mentioned problems of adhesion, a reactive modified asphalt base layer treatment agent has been proposed in the prior art, such as Chinese invention patent CN110184017A, whose raw materials include silane-modified polyurethane prepolymer, asphalt, and asphalt compatibilizer. , Silane water remover, catalyst, filler, silane coupling agent, defoamer. Although this patent can build a primer on a wet base surface, and emphasizes that it can avoid the problem of carbon dioxide bubbles generated by moisture curing in the prior art, thereby ensuring firm bonding, but it uses silane to directly drop into the terminal isocyanate. Silane-grafted polyurethane prepolymer, where silane is a conventional silane coupling agent that can react with isocyanate groups, but in actual production, especially when the amount of reaction is large, the reaction with isocyanate groups is too violent, and the reaction process is not controllable Therefore, the method used in the preparation method is dropwise addition, which is not conducive to safe production, and also makes the preparation efficiency low, which is not suitable for industrial production; at the same time, its viscosity is relatively large, which is relatively unfavorable for on-site construction.

SUMMARY OF THE INVENTION

In view of this, the technical problem to be solved by the present invention is to overcome the deficiencies in the prior art, and to provide an improved waterproof coating suitable for cement bases and having a safe and efficient preparation process, which can be directly coated during use. On the cement base with more water content, it reacts with the silicate in the cement after hydrolysis to improve the adhesion on the wet base, and at the same time, it can also have excellent bonding strength with the asphalt waterproofing membrane, especially It is able to have a faster surface drying time and moderate viscosity (basically avoiding the step of heating up before construction), which is beneficial to on-site construction.

The present invention also provides a method for preparing the above-mentioned asphalt polyurethane waterproof coating suitable for cement base.

At the same time, the invention provides a construction method of an asphalt waterproofing membrane.

In order to solve the above technical problems, a kind of technical scheme adopted by the present invention is as follows:

A bitumen polyurethane waterproof coating suitable for cement base layer, the raw material includes bitumen, compatibilizer, water scavenger, catalyst and filler, the raw material also includes end-capped polyurethane prepolymer, the end-capped polyurethane prepolymer The compound is prepared by reacting the compound represented by the formula (I) with a polyurethane prepolymer, the end-capped polyurethane prepolymer does not contain a terminal isocyanate group, the end-capped polyurethane prepolymer, the asphalt and the The mass ratio of the compatibilizer is 30-50:40-60:1;

In the formula, R ₁ , R ₂ , R ₃ and R ₄ are independently selected from C _1-8 alkyl groups, m is 1 or 2, and n is 1, 2, 3 or 4.

In the present invention, the above preferred limitations on R ₁ , R ₂ , R ₃ , R ₄ , as well as m and n can make the reaction of the compound represented by formula (I) of the present invention and the polyurethane prepolymer in a controllable range , neither too fast nor too slow, so that the entire reaction process can be carried out in a safe and controllable condition, which is convenient for industrial utilization.

According to the present invention, the end-capped polyurethane prepolymer is fully end-capped, and the feeding amount of the compound represented by the formula (I) and the polyurethane prepolymer is based on the purpose of obtaining a fully-capped polyurethane prepolymer Adjustment.

According to some preferred aspects of the present invention, the reaction temperature for the reaction of the compound represented by formula (I) with the polyurethane prepolymer is 60-100°C.

According to some preferred and specific aspects of the present invention, R ₁ , R ₂ , R ₃ , R ₄ are each independently selected from methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl Base, _{-CH2CH2CH2CH2CH3} , _{-CH ( CH3 ) CH2CH2CH3} , _{-CH2CH ( CH3 ) CH2CH3 , -CH2CH2CH ( CH3 ) 2} , -CH(C ₂ H ₅ )CH ₂ CH ₃ , -C(CH ₃ ) ₂ CH ₂ CH ₃ , -CH(CH ₃ )CH(CH ₃ ) ₂ , -CH ₂ C(CH ₃ ) ₃ or hexyl.

According to a specific aspect of the present invention, R ₁ , R ₂ , R ₃ , R ₄ are each independently selected from methyl, ethyl or propyl.

According to some preferred aspects of the present invention, the content of terminal isocyanate groups in the polyurethane prepolymer is 4-10%.

According to some embodiments of the present invention, the polyurethane prepolymer is prepared by reacting a polyol with a polyisocyanate, the polyol is a polyether polyol and/or a polyester polyol, and the polyisocyanate is selected from the group consisting of diisocyanate and A combination of one or more of its prepolymers, triisocyanates and prepolymers thereof. In some embodiments, the polyol is a combination of one or more selected from polyether diols, polyether triols, and polyester diols, such as, but not limited to, polyether diol 2000 , polyether triol 3050, polyether diol 8000, polyether diol 6000, polyether diol 1000, polyether diol 400, polyether triol 330N, etc., the polyisocyanates include But not limited to toluene diisocyanate (TDI), isophorone diisocyanate (IPDI), diphenylmethane diisocyanate (MDI), dicyclohexylmethane diisocyanate (HMDI), hexamethylene diisocyanate (HDI), Naphthine diisocyanate (NDI) and the like.

According to some preferred aspects of the present invention, the raw material further includes a silane coupling agent and/or a defoaming agent, and the silane coupling agent is vinyltriethoxysilane, vinyltrimethoxysilane or vinyltri( β-methoxyethoxy) silane; the defoamer is a physical defoamer and/or a chemical defoamer, and the physical defoamer is a polysiloxane defoamer and/or a silicone defoamer , the chemical defoamer is a combination of one or more selected from calcium oxide, magnesium oxide and calcium hydroxide. In the present invention, adding a silane coupling agent to the raw material can improve the adhesion between the waterproof coating and the cement substrate layer to a certain extent.

According to some preferred aspects of the present invention, in parts by mass, among the raw materials, 30-50 parts of end-capped polyurethane prepolymer, 40-60 parts of asphalt, 1-2 parts of compatibilizer, and 1-2 parts of water removing agent 2 parts, 0.1-0.2 parts of catalyst, 0.5-2 parts of filler, optionally 0.1-0.5 part of silane coupling agent and 0.1-0.3 part of defoaming agent.

In some embodiments of the invention, the asphalt is a combination of one or more selected from the group consisting of Road No. 10, Road No. 70, Road No. 90, Road No. 100, and Road No. 200.

In some embodiments of the present invention, the compatibilizer is polyethylene wax and/or polyacetamide wax. The above two compounds have the characteristics of high temperature, low viscosity and low temperature thixotropy. Through the selection of molecular segments, they can play both polar groups and non-polar structures, and can be fully dissolved in polyurethane and asphalt respectively. .

In some embodiments of the present invention, the water scavenger is Silane 171.

In some embodiments of the present invention, the catalyst is selected from the group consisting of dibutyltin dilaurate, stannous octoate, environmentally friendly non-butyltin catalysts, bismuth carboxylate catalysts, zinc naphthenate, and pentamethyldipropylenetriamine. , a combination of one or more of tetramethylethylenediamine and bismorpholine catalysts.

In some embodiments of the present invention, the filler is selected from fumed silica, gypsum whiskers, nano calcium carbonate, nano aluminum nitride, nano boron nitride, nano aluminum borate, heavy calcium, talc, light calcium A combination of one or more of , kaolin and wollastonite powder.

Another technical solution provided by the present invention: a preparation method of the above-mentioned asphalt polyurethane waterproof coating suitable for cement base, the preparation method comprising the following steps:

(1) Preparation of end-capped polyurethane prepolymer: first prepare a polyurethane prepolymer, then mix and react the compound represented by formula (I) with the polyurethane prepolymer to prepare the end-capped polyurethane prepolymer; wherein The molar feeding amount of the terminal amino group in the compound shown in the control formula (I) is greater than the terminal isocyanate group contained in the polyurethane prepolymer;

(2) Preparation of waterproof coating: each raw material is weighed according to the formula, mixed and made.

Another technical solution provided by the present invention: a construction method of an asphalt waterproofing membrane on a cement base, the construction method comprising: firstly coating the above-mentioned asphalt polyurethane waterproof coating suitable for the cement base on the cement base , forming a waterproof coating, and then covering the bitumen waterproofing membrane on the waterproof coating.

Due to the adoption of the above technical solutions, the present invention has the following advantages compared with the prior art:

The invention innovatively uses the specific compound of formula (1) to fully end-cap the polyurethane prepolymer, on the one hand, the process of preparing the end-capped polyurethane prepolymer can be controlled, avoid violent reaction, improve safety, and at the same time It also gives the waterproof coating the ability to be directly coated on the wet cement base layer. After the hydrolysis of the groups contained in the end-capped polyurethane prepolymer, it reacts with the silicate in the cement to improve the adhesion between the waterproof coating and the substrate layer, and It can also have excellent bonding strength with the asphalt waterproofing membrane containing the same material, especially it can have a faster surface drying time and moderate viscosity (basically avoid the step of heating before construction), which is conducive to on-site construction .

Detailed ways

The above scheme will be further described below in conjunction with specific examples; it should be understood that these examples are used to illustrate the basic principles, main features and advantages of the present invention, and the present invention is not limited by the scope of the following examples; The implementation conditions can be further adjusted according to specific requirements, and the unspecified implementation conditions are usually those in routine experiments.

In the following examples, unless otherwise specified, all raw materials were obtained from commercial sources or prepared by conventional methods in the art.

In the following, polyether diol 2000, polyether diol 1000, and polyether diol 400 were respectively purchased from Dongda University, toluene diisocyanate was BASF TDI, and diphenylmethane diisocyanate was BASF MDI;

The compounds represented by the formula (I) used in the following have the following structures respectively, which are all purchased from Evonik:

Formula (I-1): R ₁ , R ₂ , R ₃ and R ₄ are all methyl groups, and m and n are both 1;

Formula (I-2): R ₁ , R ₂ , R ₃ and R ₄ are all methyl groups, m is 2, and n is 1;

Formula (I-3): R ₁ and R ₂ are both methyl groups, R ₃ and R ₄ are both ethyl groups, m is 1, and n is 1;

Formula (I-4): R ₁ and R ₂ are both ethyl groups, R ₃ and R ₄ are both methyl groups, m is 1, and n is 1.

Example 1

This example provides an asphalt polyurethane waterproof coating suitable for cement base. In parts by mass, its raw materials include: 30 parts of end-capped polyurethane prepolymer, 60 parts of road No. 10 asphalt, 1 part of polyethylene wax, water removal 1 part of silane 171, 0.1 part of dibutyltin dilaurate, 0.5 part of fumed silica, 0.2 part of vinyltriethoxysilane, and 0.1 part of calcium oxide.

The preparation method includes the following steps:

(1) Preparation of end-capped polyurethane prepolymer:

50 parts of Dongda polyether diol 2000 was dehydrated under vacuum at 120°C and -0.1MPA to a moisture content of less than 0.05%, then mixed with 10 parts of BASF TDI and reacted at 80°C for 3 hours. The measured NCO content was about When it is 4.6%, the reaction is terminated to make 60 parts of polyurethane prepolymer;

Then, 20 parts of the compound represented by the formula (I-1) was mixed with 60 parts of the polyurethane prepolymer prepared by the above method, and reacted at 60° C. to prepare 80 parts of the end-capped polyurethane prepolymer;

(2) Preparation of waterproof coating: each raw material is weighed according to the formula, mixed and made.

Example 2

This example provides a bituminous polyurethane waterproof coating suitable for cement base. In parts by mass, its raw materials include: 40 parts of end-capped polyurethane prepolymer, 55 parts of road No. 10 asphalt, 1 part of polyethylene wax, water removal 1 part of silane 171, 0.2 part of dibutyltin dilaurate, 0.7 part of fumed silica, 0.1 part of vinyltriethoxysilane, and 0.1 part of calcium oxide.

The preparation method includes the following steps:

(1) Preparation of end-capped polyurethane prepolymer:

50 parts of Toda Polyether Diol 2000 and 25 parts of Toda Polyether Diol 1000 were dehydrated under vacuum at 120°C and -0.1MPA to a moisture content of less than 0.05%, and then mixed with 20 parts of BASF TDI in The reaction was carried out at 80°C for 3 hours, and the reaction was terminated when the NCO content was about 5.8%, and 95 parts of polyurethane prepolymer were prepared;

Then, 50 parts of the compound represented by the formula (I-2) was mixed with 95 parts of the polyurethane prepolymer prepared by the above method, and reacted at 60° C. to prepare 145 parts of the end-capped polyurethane prepolymer;

(2) Preparation of waterproof coating: each raw material is weighed according to the formula, mixed and made.

Example 3

This example provides an asphalt polyurethane waterproof coating suitable for cement base. In parts by mass, the raw materials include: 50 parts of end-capped polyurethane prepolymer, 40 parts of road No. 10 asphalt, 1 part of polyethylene wax, water removal 1 part of silane 171, 0.1 part of dibutyltin dilaurate, 0.8 part of fumed silica, 0.2 part of vinyltriethoxysilane, and 0.2 part of calcium oxide.

The preparation method includes the following steps:

(1) Preparation of end-capped polyurethane prepolymer:

25 parts of Toda Polyether Diol 400 and 25 parts of Toda Polyether Diol 1000 were dehydrated under vacuum at 120°C and -0.1MPA to a moisture content of less than 0.05%, and then mixed with 45 parts of BASF MDI in The reaction was carried out at 80°C for 2 hours, and the reaction was terminated when the NCO content was about 8.17%, and 95 parts of polyurethane prepolymer were prepared;

Then, 55 parts of the compound represented by the formula (I-3) was mixed with 95 parts of the polyurethane prepolymer prepared by the above method, and reacted at 60° C. to prepare 150 parts of the end-capped polyurethane prepolymer;

(2) Preparation of waterproof coating: each raw material is weighed according to the formula, mixed and made.

Example 4

This example provides an asphalt polyurethane waterproof coating suitable for cement base. In parts by mass, the raw materials include: 50 parts of end-capped polyurethane prepolymer, 50 parts of road No. 70 asphalt, 1 part of polyacetamide wax, 1 part of water agent silane 171, 0.1 part of dibutyltin dilaurate, 0.8 part of fumed silica, 0.1 part of vinyltriethoxysilane, and 0.2 part of calcium oxide.

The preparation method includes the following steps:

(1) Preparation of end-capped polyurethane prepolymer:

92 parts of Todai polyether diol 2000 was dehydrated under vacuum at 120°C and -0.1MPA to a moisture content of less than 0.05%, and then mixed with 17 parts of BASF TDI and reacted at 80°C? h, when the NCO content was measured to be about 4%, the reaction was terminated, and 109 parts of polyurethane prepolymers were made;

Then, 36 parts of the compound represented by the formula (I-4) was mixed with 109 parts of the polyurethane prepolymer prepared by the above method, and reacted at 60° C. to prepare 145 parts of the end-capped polyurethane prepolymer;

(2) Preparation of waterproof coating: each raw material is weighed according to the formula, mixed and made.

Comparative Example 1

It is basically the same as Example 1, except that the compound represented by formula (I-1) is replaced with a silane coupling agent in the same molar amount, such as aminotriethoxysilane.

Since the reaction between the silane coupling agent and the polyurethane prepolymer is too violent, the silane coupling agent is added dropwise to the polyurethane prepolymer for reaction when preparing the end-capped polyurethane prepolymer in the preparation method.

Comparative Example 2

Basically the same as Example 1, the difference is only that the polyurethane prepolymer is not modified by end-capping, and the same amount of the prepared polyurethane prepolymer is directly used.

Performance Testing

After the waterproof coatings obtained in the above Examples 1-4 and Comparative Examples 1-2 were formed into films, their various properties were tested, as shown in Table 1 for details.

Table 1

The above-mentioned embodiments are only to illustrate the technical concept and characteristics of the present invention, and their purpose is to enable those who are familiar with the art to understand the content of the present invention and implement them accordingly, and cannot limit the scope of protection of the present invention with this. Equivalent changes or modifications made in the spirit and spirit should all be included within the protection scope of the present invention.

Claims (10)

1. a kind of asphalt polyurethane waterproof coating that is applicable to cement base, its raw material comprises asphalt, compatibilizer, dewatering agent, catalyzer and filler, it is characterized in that, described raw material also comprises end-capped polyurethane prepolymer, described The end-capped polyurethane prepolymer is prepared by reacting the compound represented by the formula (I) with the polyurethane prepolymer, the end-capped polyurethane prepolymer does not contain terminal isocyanate groups, and the end-capped polyurethane prepolymer, The mass ratio of the asphalt and the compatibilizer is 30-50:40-60:1;

In the formula, R ₁ , R ₂ , R ₃ and R ₄ are independently selected from C _1-8 alkyl groups, m is 1 or 2, and n is 1, 2, 3 or 4. 2 . The asphalt polyurethane waterproof coating suitable for cement base according to claim 1 , wherein the reaction temperature of the compound represented by the formula (I) and the polyurethane prepolymer is 60-100° C. 3 . 3. The asphalt polyurethane waterproof coating suitable for cement base according to claim 1 or 2, wherein R ₁ , R ₂ , R ₃ , R ₄ are independently selected from methyl, ethyl, propyl, Isopropyl, n _- butyl, isobutyl, tert _- butyl, _{-CH2CH2CH2CH2CH3} , -CH _{( CH3 ) CH2CH2CH3} , -CH2CH _{( CH3 ) CH 2} CH ₃ , -CH ₂ CH ₂ CH(CH ₃ ) ₂ , -CH(C ₂ H ₅ )CH ₂ CH ₃ , -C(CH ₃ ) ₂ CH ₂ CH ₃ , -CH(CH ₃ )CH(CH ₃ ) ₂ , -CH ₂ C(CH ₃ ) ₃ or hexyl. 4 . The asphalt polyurethane waterproof coating suitable for cement base layer according to claim 1 or 2 , wherein the content of terminal isocyanate groups in the polyurethane prepolymer is 4-10%. 5 . 5. The asphalt polyurethane waterproof coating suitable for cement base according to claim 4, wherein the polyurethane prepolymer is made by reacting polyol and polyisocyanate, and the polyol is polyether polyol and/or Polyester polyol, the polyisocyanate is a combination of one or more selected from diisocyanate and its prepolymer, triisocyanate and its prepolymer. 6. The asphalt polyurethane waterproof coating suitable for cement base according to claim 1, wherein the raw material also comprises a silane coupling agent and/or a defoaming agent, and the silane coupling agent is vinyl triethyl Oxysilane, vinyltrimethoxysilane or vinyltris(β-methoxyethoxy)silane; the defoamer is a physical defoamer and/or a chemical defoamer, and the physical defoamer is For a polysiloxane defoamer and/or a silicone defoamer, the chemical defoamer is a combination of one or more selected from calcium oxide, magnesium oxide and calcium hydroxide. 7. The asphalt polyurethane waterproof coating suitable for cement base layer according to claim 1, wherein, in parts by mass, in the raw materials, 30-50 parts of end-capped polyurethane prepolymer, 40-60 parts of asphalt parts, 1-2 parts of compatibilizer, 1-2 parts of dewatering agent, 0.1-0.2 parts of catalyst, 0.5-2 parts of filler, optionally 0.1-0.5 part of silane coupling agent, 0.1-0.3 part of defoamer . 8. The asphalt polyurethane waterproofing coating suitable for cement base according to claim 7, wherein the asphalt is selected from road No. 10, road No. 70, road No. 90, road No. 100 and road No. 200 One or more combinations, the compatibilizer is polyethylene wax and/or polyacetamide wax, the water scavenger is silane 171, and the catalyst is selected from dibutyltin dilaurate, stannous octoate, A combination of one or more of environmentally friendly non-butyl tin catalysts, bismuth carboxylate catalysts, zinc naphthenate, pentamethyldipropylenetriamine, tetramethylethylenediamine and bismorpholine catalysts, the The filler is one selected from fumed silica, gypsum whiskers, nano calcium carbonate, nano aluminum nitride, nano boron nitride, nano aluminum borate, heavy calcium, talc, light calcium, kaolin and wollastonite powder. various combinations. 9. the preparation method of the bituminous polyurethane waterproof coating applicable to cement base layer described in any one of claim 1-8, is characterized in that, described preparation method comprises the steps: (1) Preparation of end-capped polyurethane prepolymer: first prepare a polyurethane prepolymer, then mix and react the compound represented by formula (I) with the polyurethane prepolymer to prepare the end-capped polyurethane prepolymer; wherein The molar feeding amount of the terminal amino group in the compound shown in the control formula (I) is greater than the terminal isocyanate group contained in the polyurethane prepolymer; (2) Preparation of waterproof coating: each raw material is weighed according to the formula, mixed and made. 10. A construction method of an asphalt waterproofing membrane on a cement base, characterized in that the construction method comprises: firstly coating the cement base as described in any one of claims 1 to 8, which is suitable for A cement-based asphalt polyurethane waterproof coating is formed to form a waterproof coating, and then the asphalt waterproof membrane is covered on the waterproof coating.