Disclosure of Invention
In view of the above, the present application provides a one-component polyurethane waterproof coating with good adhesion to a substrate and water-immersion resistance, and a preparation method thereof.
The application provides a single-component polyurethane waterproof coating in a first aspect, which comprises the following main raw materials in parts by weight:
100 parts by weight of organic silicon double-end dihydric alcohol;
40-85 parts by weight of polyether polyol;
55-70 parts by weight of diisocyanate;
40-60 parts by weight of a curing agent;
10-15 parts by weight of a tackifier;
wherein the curing agent comprises the reaction product of a siloxane having amine groups reacted with a ketone and/or an aldehyde.
According to any embodiment of the first aspect of the present application, the tackifier comprises a reaction product of a silicone oligomer reacted with an epoxy resin.
According to any embodiment of the first aspect of the present application, the curing agent comprises:
18-40 parts by weight of siloxane with amino groups;
6-30 parts by weight of ketone and/or aldehyde.
According to any of the embodiments of the first aspect of the present application, the tackifier comprises:
10-14 parts by weight of an organosilicon oligomer;
20-24 parts of epoxy resin.
According to any embodiment of the first aspect of the present application, the diisocyanate comprises at least one of an aromatic diisocyanate and an aliphatic diisocyanate.
According to any embodiment of the first aspect of the present application, the waterproof coating further comprises:
0 to 15 parts by weight of hexamethylene diisocyanate trimer;
20-35 parts by weight of a plasticizer;
120-160 parts of pigment and filler;
0.5-4 parts by weight of a catalyst;
3-6 parts of a chain extender;
25-40 parts of solvent.
The second aspect of the present application provides a method for preparing a one-component polyurethane waterproof coating, comprising:
mixing organic silicon double-end dihydric alcohol, polyether polyol and a filler to obtain first slurry;
adding diisocyanate and other auxiliary agents into the first slurry and reacting for a first preset time to obtain a polyurethane prepolymer;
adding a curing agent and a tackifier into the polyurethane prepolymer and reacting for a second preset time to obtain a single-component polyurethane waterproof coating;
wherein the curing agent comprises the reaction product of a siloxane having amine groups reacted with a ketone and/or an aldehyde.
According to any embodiment of the second aspect of the present application, mixing the silicone double terminal diol, the polyether polyol, and the filler to obtain the first slurry comprises:
and mixing and uniformly dispersing the organic silicon double-end dihydric alcohol, the polyether polyol, the plasticizer and the pigment and filler to obtain a first slurry.
According to any embodiment of the second aspect of the present application, adding diisocyanate and other auxiliary agents to the first slurry and reacting for a first predetermined time to obtain a polyurethane prepolymer comprises:
stirring and heating the first slurry to 100-110 ℃ under the condition that the vacuum degree is-0.08 MPa to-0.1 MPa, and dehydrating for 2-3 h to obtain a first mixture;
cooling the first mixture to 70-80 ℃, adding diisocyanate, hexamethylene diisocyanate trimer and a solvent, stirring and mixing to obtain a second mixture, wherein the diisocyanate is gradually added;
adding a catalyst into the second mixture, heating to 75-85 ℃, and reacting for 3-4 h to obtain a third mixture; wherein the adding amount of the catalyst is 1/4-1/2 of the formula amount of the catalyst;
and adding a chain extender into the third mixture, and reacting for 0.5-1 h at the temperature of 75-85 ℃ to obtain the polyurethane prepolymer.
According to any embodiment of the second aspect of the present application, the step of adding a curing agent and a tackifier to the polyurethane prepolymer and reacting for a second predetermined time to obtain the one-component polyurethane waterproof coating comprises:
cooling the polyurethane prepolymer to 70-80 ℃, adding a curing agent, and stirring for reaction for 0.5-1 h to obtain a fourth mixture;
cooling the fourth mixture to 50-60 ℃, adding the tackifier and the rest of the catalyst, and stirring for reaction for 0.5-1 h;
cooling to below 50 ℃, charging nitrogen for protection, discharging to obtain the single-component polyurethane waterproof coating.
Compared with the prior art, the method has the following beneficial effects:
the self-made curing agent and the tackifier are introduced into the single-component polyurethane waterproof coating, wherein primary amine released after hydrolysis of the curing agent can perform a curing reaction with isocyanate to improve the crosslinking density of a coating product and enhance the water immersion resistance of the coating product; in addition, after the terminal siloxane in the curing agent is hydrolyzed, high-activity terminal hydroxyl can be released, and the high-activity terminal hydroxyl can react with hydroxyl and other groups on the surface of the base material to realize a coupling effect, so that the adhesion of the coating and the base material is improved.
Detailed Description
In order to make the application purpose, technical solution and beneficial technical effects of the present application clearer, the present application is further described in detail with reference to the following embodiments. It should be understood that the embodiments described in this specification are only for the purpose of explaining the present application and are not intended to limit the present application.
For the sake of brevity, only some numerical ranges are explicitly disclosed herein. However, any lower limit may be combined with any upper limit to form ranges not explicitly recited; and any lower limit may be combined with any other lower limit to form a range not explicitly recited, and similarly any upper limit may be combined with any other upper limit to form a range not explicitly recited. Also, although not explicitly recited, each point or individual value between endpoints of a range is encompassed within the range. Thus, each point or individual value can form a range not explicitly recited as its own lower or upper limit in combination with any other point or individual value or in combination with other lower or upper limits.
In the description herein, it is to be noted that, unless otherwise specified, "above" and "below" are inclusive, and "a plurality" of "one or more" means two or more.
The above summary of the present application is not intended to describe each disclosed embodiment or every implementation of the present application. The following description more particularly exemplifies illustrative embodiments. At various points throughout this application, guidance is provided through a list of embodiments that can be used in various combinations. In each instance, the list is merely a representative group and should not be construed as exhaustive.
The first aspect of the embodiment of the application provides a single-component polyurethane waterproof coating, which comprises the following main raw materials in parts by weight: 100 parts by weight of organic silicon double-end dihydric alcohol; 40-85 parts by weight of polyether polyol; 55-70 parts by weight of diisocyanate; 40-60 parts by weight of a curing agent; 10-15 parts by weight of a tackifier; wherein the curing agent comprises the reaction product of a siloxane having amine groups reacted with a ketone and/or an aldehyde.
The self-made curing agent and the tackifier are introduced into the single-component polyurethane waterproof coating, wherein primary amine released after hydrolysis of the curing agent can perform a curing reaction with isocyanate to improve the crosslinking density of a coating product and enhance the water immersion resistance of the coating product; in addition, after the terminal siloxane in the curing agent is hydrolyzed, high-activity terminal hydroxyl can be released, and the high-activity terminal hydroxyl can react with hydroxyl and other groups on the surface of the base material to realize a coupling effect, so that the adhesion of the coating and the base material is improved.
In some embodiments, the adhesion promoter comprises the reaction product of a silicone oligomer reacted with an epoxy resin. In some embodiments, the tackifier is a silicone modified epoxy resin; preferably, the silicone-modified epoxy resin is formed by reacting a silicone oligomer having a plurality of unhydrolyzed alkoxy groups with an epoxy resin.
In the embodiment of the application, a certain amount of active alkoxy, epoxy and hydroxyl are remained on the molecular structure of the generated organosilicon modified epoxy resin, so that the excellent characteristics of the organosiloxane and the epoxy resin, especially the excellent adhesive property of the epoxy resin to a cement substrate, are still remained.
In some embodiments, the curing agent comprises: 18-40 parts by weight of siloxane with amino groups; 6-30 parts by weight of ketone and/or aldehyde.
In some embodiments, the siloxane having an amine group has the formula (1):
in the formula (1), R1Is alkyl or (CH)2)nN(n≥1),R2Is an alkyl group.
As a specific example, the siloxane with amine groups may have the formula:
in some embodiments, the reaction of the amine group-bearing siloxane with the ketone and/or aldehyde to form the curing agent can be as shown in formula (2) below:
in the formula (2), R is H or alkyl, R0Is alkyl, R1Is alkyl or (CH)2)nN,R2Is alkyl, n is more than or equal to 1.
In some embodiments, the ketone and/or aldehyde comprises a ketone and/or aldehyde blocking agent; preferably, the ketone and/or aldehyde blocking agent comprises at least one of acetone, methyl ethyl ketone, methyl propyl ketone, diethyl ketone, methyl butyl ketone, methyl isobutyl ketone, methyl tert-butyl ketone, diisobutyl ketone, cyclohexanone, cyclopentanone, formaldehyde, acetaldehyde, butyraldehyde, isobutyraldehyde, and tetrahydrobenzaldehyde.
As a specific example, the curing agent may be prepared as follows:
putting siloxane with amido into a reactor, adding toluene, starting stirring until the siloxane with amido is completely dissolved; adding excessive ketone and/or aldehyde blocking agent (wherein the mass ratio of the siloxane with amino to the ketone and/or aldehyde blocking agent is 1: 2) into a reactor, heating in an oil bath, stirring, reacting, heating to about 110 ℃, starting refluxing until no obvious condensation water flows out, and then heating to 115-125 ℃ for continuing reaction for 3 hours; then, normal pressure distillation is carried out, and water, toluene and excessive sealant in the reactor are evaporated; finally, vacuumizing, distilling under reduced pressure, cooling and discharging to obtain the curing agent with the active siloxane.
In the embodiment of the application, after the curing agent is hydrolyzed by contacting with water vapor, the blocked amine carried by the curing agent is preferentially deblocked to release primary amine, and the primary amine can perform a curing reaction with isocyanate; meanwhile, the terminal siloxane in the curing agent can release high-activity terminal hydroxyl after hydrolysis, and the high-activity terminal hydroxyl realizes the coupling effect through the reaction with hydroxyl and other groups on the surface of the base material, so that the adhesion of the single-component polyurethane waterproof coating and the base material is directly improved.
In some embodiments, the tackifier comprises: 10-14 parts by weight of an organosilicon oligomer; 20-24 parts of epoxy resin.
In some embodiments, the reaction of the silicone oligomer and the epoxy resin in the tackifier may be as shown in formula (3) below:
in some embodiments, the silicone oligomer includes at least one of monomethyltriethoxysilane, dimethyldiethoxysilane, and monophenyltriethoxysilane. In some embodiments, the epoxy resin includes at least one of E51 and E20.
As a specific example, the tackifier may be prepared as follows:
adding one of methyl triethoxysilane, dimethyl diethoxy silane and phenyl triethoxysilane and xylene solvent into a reactor;
starting a stirring device, heating to 50 ℃, keeping constant temperature, starting to dropwise add the mixed solution of deionized water and hydrochloric acid, and continuing to react for 2.5 hours after dropwise addition;
after the reaction is finished, distilling under normal pressure and then distilling under reduced pressure, evaporating ethanol and part of water generated in the reaction, and cooling to room temperature to obtain the organosilicon oligomer which is not completely hydrolyzed and contains active ethoxy;
adding a certain amount of epoxy resin and an organic solvent into a four-mouth bottle provided with a stirring device and a reflux condenser, introducing condensed water, stirring, gradually heating to 70 ℃, and preserving heat to completely melt the epoxy resin;
adding the organic silicon oligomer prepared in the step into a four-mouth bottle, adding a catalyst tetrabutyl orthotitanate, stirring, and gradually heating to 150 ℃;
separating out the organic solvent by an oil-water separator, and then carrying out heat preservation reaction for 1.5 h;
cooling to below 50 deg.C, and discharging.
In the embodiment of the application, the tackifier which is obtained by reacting the organic silicon oligomer with the epoxy resin is utilized, a certain amount of active alkoxy, epoxy and hydroxyl are reserved in the structure of the tackifier, and the groups can generate a strong bonding effect on the base material, so that the bonding performance of the single-component polyurethane waterproof coating to the base material is improved.
In some embodiments, the diisocyanate includes at least one of an aromatic diisocyanate and an aliphatic diisocyanate; as a specific example, the diisocyanate may be toluene diisocyanate or diphenylmethane diisocyanate.
In some embodiments, the water resistant coating further comprises: 0 to 15 parts by weight of hexamethylene diisocyanate trimer; 20-35 parts by weight of a plasticizer; 120-160 parts of pigment and filler; 0.5-4 parts by weight of a catalyst; 3-6 parts of a chain extender; 25-40 parts of solvent.
In some embodiments, the hexamethylene diisocyanate trimer is used in an amount of 0 to 15 parts by weight; preferably, the hexamethylene diisocyanate trimer is used in an amount of 10 to 11 parts by weight.
In some embodiments, the plasticizer comprises at least one of diisononyl phthalate, trioctyl phosphate, citrate esters, and chlorinated paraffin-based plasticizers.
In some embodiments, the pigment filler comprises at least one of nano calcium carbonate, fumed silica, and rutile titanium dioxide.
In some embodiments, the catalyst comprises at least one of dibutyltin dilaurate, stannous octoate, and lead isooctanoate.
In some embodiments, the chain extender comprises at least one of trimethylolpropane, 1, 4-butanediol, ethylene glycol, propylene glycol, neopentyl glycol, and 1,6 hexanediol.
In some embodiments, the solvent comprises at least one of ethyl acetate, propylene glycol methyl ether acetate, butyl acetate, xylene, and trimethylbenzene.
The self-made curing agent and the tackifier are introduced into the single-component polyurethane waterproof coating provided by the embodiment of the application, wherein primary amine released after hydrolysis of the curing agent can be subjected to curing reaction with isocyanate, terminal siloxane in the curing agent can be hydrolyzed to release high-activity terminal hydroxyl, and the high-activity terminal hydroxyl can be reacted with hydroxyl and other groups on the surface of a base material to realize a coupling effect, so that the adhesion of the coating and the base material is improved; in addition, terminal hydroxyl groups generated after hydrolysis of terminal siloxane in the curing agent can be condensed with hydroxyl groups generated after hydrolysis of active alkoxy in the tackifier to form a crosslinked network elastomer, so that the crosslinking density of the product is improved, and primary amine groups generated by hydrolysis of the curing agent can react with epoxy groups generated by hydrolysis of the tackifier to further improve the crosslinking density of the product, thereby improving the water immersion resistance of the product; therefore, the bonding property and the water immersion resistance of the single-component polyurethane waterproof coating are improved through the introduced curing agent, the introduced tackifier and the synergistic effect of the curing agent and the tackifier.
In a second aspect, embodiments of the present application provide a method for preparing a one-component polyurethane waterproof coating, including:
mixing organic silicon double-end dihydric alcohol, polyether polyol and a filler to obtain first slurry;
adding diisocyanate and other auxiliary agents into the first slurry and reacting for a first preset time to obtain a polyurethane prepolymer;
adding a curing agent and a tackifier into the polyurethane prepolymer and reacting for a second preset time to obtain a single-component polyurethane waterproof coating;
wherein the curing agent comprises the reaction product of a siloxane having amine groups reacted with a ketone and/or an aldehyde.
In the embodiment of the application, a self-made curing agent and a tackifier are introduced into a reaction system of the single-component polyurethane waterproof coating, wherein terminal hydroxyl groups generated after hydrolysis of terminal siloxane in the curing agent can be condensed with hydroxyl groups generated after hydrolysis of active alkoxy in the tackifier to form a cross-linked network elastomer so as to realize cross-linking and curing, so that the cross-linking density is improved, and the bridging effect of the alkoxy is fully exerted; meanwhile, epoxy groups in the tackifier can react with primary amine groups released by hydrolysis of the curing agent to further improve the crosslinking density, so that the hydrolysis resistance of the single-component polyurethane waterproof coating is improved through the synergistic effect between the curing agent and the tackifier.
In some embodiments, mixing the silicone double terminal diol, the polyether polyol, and the filler to obtain the first slurry in the above step comprises: mixing and uniformly dispersing organic silicon double-end dihydric alcohol, polyether polyol, a plasticizer and pigment and filler to obtain first slurry; wherein the filler comprises a mixture of a plasticizer and a pigment filler.
In some embodiments, the polyether polyol comprises at least one of the blue star east trifunctional polyether polyol EP330N and the polyether polyol MN 1000.
In some embodiments, the molecular weight of the organosilicon double-ended diol is 1000 to 4000, and the molecular structural formula is shown as the following formula (4):
in the formula (4), R1Is an alkyl group; preferably, n = 8~ 50.
Preferably, the organic silicon double-end dihydric alcohol is at least one of Shanghai Tiger tech-2120 and hydroxypropyl silicone oil SC-HP6002 of En chemical industry Co. In some embodiments, the dispersing in the above step may be performed in a strong disperser.
In some embodiments, the step of adding diisocyanate and other auxiliary agents to the first slurry and reacting for a first predetermined time to obtain the polyurethane prepolymer comprises:
stirring and heating the first slurry to 100-110 ℃ under the condition that the vacuum degree is-0.08 MPa to-0.1 MPa, and dehydrating for 2-3 h to obtain a first mixture;
cooling the first mixture to 70-80 ℃, adding diisocyanate, hexamethylene diisocyanate trimer and a solvent, stirring and mixing to obtain a second mixture, wherein the diisocyanate is gradually added;
adding a catalyst into the second mixture, heating to 75-85 ℃, and reacting for 3-4 h to obtain a third mixture; wherein the adding amount of the catalyst is 1/4-1/2 of the formula amount of the catalyst;
and adding a chain extender into the third mixture, and reacting for 0.5-1 h at the temperature of 75-85 ℃ to obtain the polyurethane prepolymer.
In some embodiments, the other auxiliary agents in the above step comprise hexamethylene diisocyanate trimer, a catalyst, a chain extender and a solvent.
In some embodiments, the dropping rate of the diisocyanate in the above step may be selected to be 1 to 2 parts by weight/second; the addition amount of the catalyst can be 1/4-1/2 of the formula amount; preferably, the amount of catalyst added is 1/3 of the formula amount.
In the embodiment of the application, the reaction of the organosilicon double-ended diol and the organosilicon single-ended diol with isocyanate can form a polyurethane prepolymer with a siloxane bond (Si-O-Si) chain segment structure with high stability and low surface energy, and the structure has certain hydrophobic property, so that the water absorption of a coating film can be reduced, and the degradation of the coating film is delayed.
In some embodiments, the step of adding the curing agent and the tackifier into the polyurethane prepolymer and reacting for a second preset time to obtain the one-component polyurethane waterproof coating comprises:
cooling the polyurethane prepolymer to 70-80 ℃, adding a curing agent, and stirring for reaction for 0.5-1 h to obtain a fourth mixture;
cooling the fourth mixture to 50-60 ℃, adding the tackifier and the rest of the catalyst, and stirring for reaction for 0.5-1 h;
cooling to below 50 ℃, charging nitrogen for protection, discharging to obtain the single-component polyurethane waterproof coating.
In the embodiment of the application, organosilicon double-ended dihydric alcohol, organosilicon single-ended dihydric alcohol and isocyanate are used for reacting to synthesize a polyurethane prepolymer with a siloxane bond (Si-O-Si) chain segment structure with high stability and low surface energy; then introducing reactive alkoxy silane into the polyurethane prepolymer by grafting, wherein the reactive alkoxy silane can form a siloxane (Si-O-Si) crosslinking network with low surface energy after hydrolytic condensation with the chain end of the prepolymer; meanwhile, the organic silicon modified epoxy resin with good system compatibility is added, and by means of the excellent adhesive property of the epoxy resin to a cement base material and the cross-linked network elastomer formed by hydrolysis condensation of the active alkoxy and the prepolymer, the product has excellent adhesive property and water immersion resistance, and the problems of poor adhesion of the traditional one-component polyurethane waterproof coating to the cement base material, poor water resistance and the like are solved.
Examples
The present disclosure is more particularly described in the following examples that are intended as illustrative only, since various modifications and changes within the scope of the present disclosure will be apparent to those skilled in the art. Unless otherwise indicated, all parts, percentages, and ratios reported in the following examples are on a weight basis, and all reagents used in the examples are commercially available or synthesized according to conventional methods and can be used directly without further treatment, and the equipment used in the examples is commercially available.
Example 1
A single-component polyurethane waterproof coating comprises the following raw materials in parts by weight: tech-2120 (Mn = 2000), 25 parts by weight; EP330N (Mn = 5000), 15 parts by weight; trioctyl phosphate (99% content), 7 parts by weight; XTCC nano active calcium carbonate, 20 weight portions; LM-150 fumed silica, 15 parts by weight; TDI-80, 15 weight portions; HDI trimer (HT-100), 3 parts by weight; 1.2 parts by weight of propylene glycol; 12 parts of curing agent; 3 parts of tackifier; 0.2 weight part of stannous octoate; butyl acetate, 8 parts by weight.
Example 2
A single-component polyurethane waterproof coating comprises the following raw materials in parts by weight: tech-2120 (Mn = 2000), 22 parts by weight; EP330N (Mn = 5000), 18 parts by weight; trioctyl phosphate (99% content), 7 parts by weight; XTCC nano active calcium carbonate, 22 weight portions; LM-150 fumed silica, 13 parts by weight; TDI-80, 15 weight portions; HDI trimer (HT-100), 3 parts by weight; 1.3 parts by weight of propylene glycol; 13 parts of curing agent; 3 parts of tackifier; 0.2 weight part of stannous octoate; butyl acetate, 8 parts by weight.
Example 3
A single-component polyurethane waterproof coating comprises the following raw materials in parts by weight: tech-2120 (Mn = 2000), 22 parts by weight; EP330N (Mn = 5000), 18 parts by weight; trioctyl phosphate (99% content), 7 parts by weight; XTCC nano active calcium carbonate, 22 weight portions; LM-150 fumed silica, 13 parts by weight; TDI-80, 15 weight portions; HDI trimer (HT-100), 0 part by weight; 1.3 parts by weight of propylene glycol; 13 parts of curing agent; 3 parts of tackifier; 0.2 weight part of stannous octoate; butyl acetate, 8 parts by weight.
Example 4
A single-component polyurethane waterproof coating comprises the following raw materials in parts by weight: tech-2120 (Mn = 2000), 28 parts by weight; EP330N (Mn = 5000), 11 parts by weight; trioctyl phosphate (99% content), 6 parts by weight; XTCC nano active calcium carbonate, 20 weight portions; LM-150 fumed silica, 15 parts by weight; TDI-80, 16 weight portions; HDI trimer (HT-100), 3 parts by weight; 1.2 parts by weight of propylene glycol; 11 parts of curing agent; 3 parts of tackifier; 0.2 weight part of stannous octoate; butyl acetate, 7 parts by weight.
The sources of the raw materials in the above examples are as follows: tech-2120 available from Shanghai tag Polymer technology, Inc.; EP330N, available from eastern blue Star east Co., Ltd; trioctyl phosphate, available from Wuhanrong Brilliant Biotech, Inc.; nano calcium carbonate, purchased from shanxi xintai constant-belief nanomaterial co; fumed silica, available from Shanghai Pieris Linnaeus chemical Co., Ltd; TDI, available from Dow chemical company; HDI trimer, available from Vanhua chemical group, Inc.; propylene glycol, purchased from Guangdong Qing Zhixing Biotech, Inc.; curing agent, self-made; tackifier, self-made; stannous octoate, available from neotypical chemical materials (shanghai) ltd; butyl acetate, available from Anda chemical Co., Ltd, Hangzhou city.
The preparation method of the single-component polyurethane waterproof coating in the above embodiments 1 to 4 is as follows:
adding organic silicon double-end dihydric alcohol, polyether polyol, a plasticizer and pigment filler into a strong dispersing machine, and uniformly dispersing;
transferring the dispersed slurry into a reaction kettle, stirring and heating to 100-110 ℃, and dehydrating for 2-3 h under the relative vacuum degree of-0.08 MPa-0.1 MPa;
reducing the temperature to 70-80 ℃, adding a solvent, then gradually adding diisocyanate and hexamethylene diisocyanate trimer, controlling the dropping speed to be 1-2 parts by weight/second, stirring, then adding 1/4-1/2 formula amount of catalyst, heating to 75-85 ℃, and reacting for 3-4 hours;
adding a chain extender, and reacting at 75-85 ℃ for 0.5-1 h;
cooling to 70-80 ℃, adding a curing agent, and stirring for 0.5-1 h;
cooling to 50-60 ℃, adding the catalyst and the tackifier in the rest formula amount, and stirring for 0.5-1 h;
cooling to below 50 deg.C, introducing nitrogen for protection, and discharging.
The raw material ratios of the above examples 1 to 4 and comparative examples 1 to 4 are shown in the following table 1:
TABLE 1
Wherein comparative example 1 is similar in composition and preparation to example 1, except that no curing agent is included in comparative example 1; comparative example 2 is similar in composition and preparation to example 1, except that no tackifier is included in comparative example 2; comparative example 3 is similar in composition and preparation to example 1 except that no tackifier is included in comparative example 3 and the conventional latent curative 3-hydroxyethyl-1, 3-oxazolidine is substituted for the curative in example 1 in comparative example 3; comparative example 4 is similar in composition and preparation to example 1 except that in comparative example 4 the curing agent of example 1 is replaced with the conventional latent curing agent 3-hydroxyethyl-1, 3-oxazolidine.
Test section
The single-component polyurethane waterproof coatings in the above examples 1 to 4 and comparative examples 1 to 4 were subjected to the related physical and mechanical property tests, and the test results are shown in the following table 2:
TABLE 2
The relevant tests in Table 2 are carried out according to GB/T19250-2013 and GB/T16777-2008 standards.
The method for testing the adhesiveness of the foam in the above performance test was as follows (all samples were prepared according to the method of GB/T16777-20087.1A in the test):
maintaining for 7 days under standard test conditions (temperature (23 + -2) ° C, relative humidity (50 + -10)%), and testing initial bonding strength; soaking in water for a preset time, taking out, placing under standard test conditions, standing for 12h, and then testing the bonding strength; wherein the strength retention = bond strength 100%/initial bond strength.
Comparing and analyzing the examples 1-4 and the comparative examples 1-4, it can be seen that the curing agent and the tackifier are used in combination in the formula system of the examples 1-4, and the product has excellent performance in all aspects; example 3 HDI trimer was not used, the surface drying time and the solid drying time of the product were relatively long, and the tensile strength and the tear strength were reduced to some extent.
As can be seen from Table 2, the water-soaking adhesion performance of the products in comparative examples 1 and 2 is obviously reduced compared with that in example 1, the strength retention rate of the products in comparative examples 1 and 2 after soaking in water for 7 days is obviously reduced compared with that in example 1, the failure modes are cohesive failure, and the adhesion strength is greatly reduced along with the prolonging of the water soaking time. Compared with comparative examples 1-4, it is obvious that examples 1-4 using the curing agent and the tackifier in combination still have good strength retention rate after being soaked in water for 30 days, the destructive form of the test piece still keeps cohesive failure, the bonding effect on the base material still keeps excellent, and the synergistic effect of the curing agent and the tackifier is demonstrated. Comparative example 3 the adhesive strength was most severely reduced, the failure form was interfacial failure after soaking for 7 days, and the strength retention after soaking was the lowest in all examples and comparative examples.
According to the embodiment 1-4, the single-component polyurethane waterproof coating disclosed by the embodiment of the application has the advantages that the adhesion and the water immersion resistance of the single-component polyurethane waterproof coating to a base material are improved through the synergistic effect between the introduced curing agent and the tackifier, and the adaptability of a product to the environment is improved.
While the invention has been described with reference to specific embodiments, the scope of the invention is not limited thereto, and those skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the invention. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.