Copolymer and radix asparagi polyurea coating composition

Abstract

The invention provides a copolymer and radix asparagi polyurea coating composition, and relates to the technical field of polyurea coatings. The copolymer comprises the following raw material components in percentage by weight: 13-30% of dialkyl maleate and the balance of one or a combination of two or more of an acrylate monomer and a styrene monomer, the acrylate monomer and the styrene monomer are respectively reactive inert with the isocyanate group at 60 DEG C; the radix asparagi polyurea coating contains a certain amount of the copolymer, so that the pot life can be obviously prolonged, but the influence on the surface drying time and the hard drying time is relatively low, and the influence on other properties is also relatively small.

Description

Technical Field

[0001] The invention belongs to the technical field of polyurea coatings and relates to a copolymer and an asparagine polyurea coating composition. Background Art

[0002] Aspartic acid ester polyurea coating has the characteristics of good weather resistance and high bonding strength, and has been widely used in many occasions. The structure of aspartic acid ester resin used in aspartic acid ester polyurea coating is different, and the prepared polyurea coating has significantly different application period, surface drying time and actual drying time. For example, the application period, surface drying time and actual drying time of Feiyang Junyan Company's F420 resin are shorter; while the application period, surface drying time and actual drying time of Feiyang Junyan Company's F520 resin are longer. In order to make aspartic acid ester polyurea coating have a moderate application period and a more relaxed construction time, part of F420 resin is generally replaced by F520 resin, that is, F420 resin and F520 resin are compounded, such as F420 resin and F520 resin are combined in a ratio of 2:1, and HT-600 is used as a curing agent. The application period, surface drying time and actual drying time are 20min, 20min and 90min respectively, which cannot achieve the effect of longer application period and faster drying.

[0003] Therefore, there is an urgent need for an aspartic ester polyurea coating that has a longer pot life while having little effect on the surface dry time and / or the through dry time. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a copolymer and an aspartame polyurea coating composition.

[0005] The technical solution of the present invention is as follows:

[0006] A copolymer, wherein the raw material components, based on 100% by weight, comprise 13-30% of dialkyl maleate, and the remainder is one or a combination of two or more of acrylic acid ester monomers and styrene monomers;

[0007] The acrylic ester monomer and the styrene monomer are respectively inert to react with isocyanate groups at 60°C.

[0008] Preferably, the general formula of the dialkyl maleate is R 1 OOCCH=CHCOOR 2 , where R 1 and R 2 Independently selected from C1-C8 alkyl.

[0009] Preferably, the general formula of the acrylate monomer is CH2=C(R 3 )COOR 4 , where R 3 is selected from H or C1-C4 alkyl, R4 Selected from C1-C18 alkyl or C2-C18 substituted alkyl.

[0010] More preferably, the R 4 The molar proportion of C4-C18 alkyl is not less than 10%.

[0011] Preferably, the R 4 The molar proportion of the methyl group is not less than 20%.

[0012] Preferably, the styrene monomer is selected from one or a combination of two or more of styrene, 3-methylstyrene and 4-methylstyrene.

[0013] An asparagus polyurea coating composition, consisting of component A and component B;

[0014] The component A comprises 20-50% aspartic acid ester resin and 3-25% of the copolymer described in any one of the above embodiments, and the balance is one or a combination of two or more of fillers, additives and pigments, based on 100% by weight;

[0015] The B component comprises an isocyanate curing agent;

[0016] The molar ratio of the NH groups in the A component to the NCO groups in the B component is 1:0.95-1.2.

[0017] Preferably, the weight content of the aspartic acid ester resin is 23-40%.

[0018] Preferably, the weight content of the copolymer is 5-20%.

[0019] Preferably, the weight percentage of the isocyanate curing agent in the component B is not less than 80%.

[0020] The beneficial effects of the present invention are:

[0021] (1) The copolymer of the present invention contains dialkyl maleate monomers, which have good compatibility with aspartic acid ester resins. In addition, the copolymer does not contain active groups such as hydroxyl, amino, and carboxyl groups, and will not accelerate the curing of aspartic acid polyurea coatings and affect the operating time.

[0022] (2) Adding a certain amount of the copolymer of the present invention to the asparagus polyurea coating can significantly extend the applicable period, which can be as long as 1 hour or more, and the construction time is flexible, but the effect on the surface drying time and the actual drying time is small, and relatively fast curing can still be achieved. Moreover, the cured polyurea coating also has good performance.

[0023] (3) The copolymer of the present invention is particularly suitable for the asparagine polyurea coating system using the F420 resin of Feiyang Junyan Company as the main resin. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is further illustrated and described below through specific implementation methods.

[0025] In order to solve the problem that the asparagine polyurea coating in the prior art cannot have a suitable drying speed while extending the application period, on the one hand, the present invention provides a copolymer, wherein the raw material components are 100% by weight, comprising 13-30% dialkyl maleate, and the remainder is one or a combination of two or more of an acrylate monomer and a styrene monomer;

[0026] Acrylate monomers and styrene monomers are respectively inert to the isocyanate groups at 60°C.

[0027] The copolymer raw material components of the present invention contain dialkyl maleate, and the copolymer has good compatibility with aspartic acid ester resin, which avoids the inability to exert the effect of the copolymer or the occurrence of adverse effects due to compatibility problems. In addition, the acrylate monomer and the styrene monomer are respectively inert to the isocyanate group at 60°C, that is, the acrylate monomer and the styrene monomer do not contain groups containing active hydrogen such as hydroxyl, amino, carboxyl, etc., which can avoid the curing acceleration effect on the aspartic acid polyurea coating, resulting in the problems of shortened application period and too fast drying of the aspartic acid polyurea coating; in addition, the acrylate monomer and the styrene monomer contain groups containing active hydrogen such as hydroxyl, amino, carboxyl, etc., which also easily lead to poor compatibility of the copolymer with the aspartic acid ester resin, and even partial incompatibility.

[0028] For example, the weight proportion of dialkyl maleate in the raw material components of the copolymer can be any value of 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, etc., without special restrictions. Considering that the rate of dialkyl maleate under free radical polymerization is much slower than that of acrylate monomers and styrene monomers, if the weight proportion is too large, it will affect the polymerization reaction of the raw material components of the copolymer, or there will be more unreacted dialkyl maleate in the system after the reaction, which will affect the performance of the copolymer. Preferably, the weight proportion of dialkyl maleate in the raw material components of the copolymer can be 13-22%.

[0029] In a preferred embodiment of the present invention, the general formula of dialkyl maleate is R 1 OOCCH=CHCOOR 2 , where R 1 and R 2independently selected from C1-C8 alkyl. For example, the dialkyl maleate may be diethyl maleate, dibutyl maleate, diisobutyl maleate, isooctyl maleate, etc. More preferably, the above R 1 and R 2 The C2-C8 alkyl group can be selected independently without affecting the adhesion of the aspartame polyurea coating composition to the substrate after curing.

[0030] In a preferred embodiment of the present invention, the general formula of the acrylate monomer is CH2=C(R 3 )COOR 4 , where R 3 is selected from H or C1-C4 alkyl, R 4 Selected from C1-C18 alkyl or C2-C18 substituted alkyl. Acrylate monomer has high polymerization activity, and under the action of free radical initiator, polymerization speed is fast. For example, in the present invention, acrylate monomer can be methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate and octadecyl (meth) acrylate, etc. More preferably, acrylate monomer can be composed of hard monomer and soft monomer, hard monomer is generally methyl (meth) acrylate, soft monomer includes butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate and octadecyl (meth) acrylate, etc. The hardness of dialkyl maleate is between hard monomer and soft monomer, and the soft and hardness of copolymer can be better adjusted, so that copolymer and aspartic acid resin have good compatibility.

[0031] In a more preferred embodiment of the present invention, R 4 The molar proportion of C4-C18 alkyl in the 4 When it is a C4-C18 alkyl group, the acrylate monomer is a soft monomer and can provide the copolymer with better softness. 4 The molar proportion of C4-C18 alkyl groups can be any value among 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, etc., without any particular limitation.

[0032] In a preferred embodiment of the present invention, R 4 The molar proportion of methyl groups in the 4 When R is methyl, the acrylate monomer is a hard monomer, especially methyl methacrylate, which can adjust the hardness and softness of the copolymer. 4 The molar percentage of the methyl group may be any value such as 20%, 25%, 30%, 35%, 40%, 45%, 50%, etc., without any particular limitation.

[0033] In a preferred embodiment of the present invention, the styrene monomer is monofunctional, that is, one styrene monomer molecule contains only one carbon-carbon double bond, and the styrene monomer can be selected from one or a combination of two or more of styrene, 3-methylstyrene and 4-methylstyrene. The styrene monomer has a high polymerization reaction activity, and under the action of a free radical initiator, the polymerization speed is relatively fast.

[0034] The copolymer of the present invention can be prepared by free radical polymerization. Specifically, each raw material component can be added to an organic solvent and subjected to polymerization reaction under the action of a free radical initiator to obtain a copolymer solution. In the present invention, in some application occasions, the copolymer solution can be used directly.

[0035] On the other hand, the present invention also provides an asparagine polyurea coating composition, which consists of component A and component B;

[0036] Component A comprises 20-50% aspartic acid ester resin and 3-25% of the copolymer described in any one of the above embodiments, and the balance is one or a combination of two or more of fillers, additives and pigments, based on 100% by weight;

[0037] Component B contains an isocyanate curing agent;

[0038] The molar ratio of NH groups in component A to NCO groups in component B is 1:0.95-1.2.

[0039] In the asparagine polyurea coating composition of the present invention, adding part of the above copolymer and replacing the aspartic acid ester resin can significantly improve the application life of the asparagine polyurea coating, but the effect on its drying rate is relatively low, the surface drying time and the actual drying time change slightly, and the effect on the bonding performance, mechanical properties, weather resistance and other properties of the asparagine polyurea coating is very low. Therefore, the asparagine polyurea coating composition of the present invention significantly extends the application life on the basis of the existing asparagine polyurea coating, and is particularly suitable for the case where the asparagine ester resin is the F420 resin of Feiyang Junyan Company, achieving the effects of long application life and rapid drying, and taking into account the operation time, construction efficiency and curing efficiency of the coating.

[0040] In the present invention, if the weight content of the copolymer in component A is too low, the effect of the copolymer is not obvious, and if the weight content of the copolymer is too high, the performance of the asparagine polyurea coating, such as curing performance, will be affected. For example, the weight content of the copolymer can be any value of 3%, 5%, 7%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, etc., without special restrictions. The molar ratio of the NH group in component A to the NCO group in component B can be any value of 1:0.95, 1:0.98, 1:1, 1:1.02, 1:1.03, 1:1.05, 1:1.07, 1:1.08, 1:1.1, 1:1.12, 1:1.13, 1:1.15, 1:1.17, 1:1.18, 1:1.2, etc., without special restrictions. Further, the molar ratio of the NH groups in component A to the NCO groups in component B may be 1:1.02-1.08.

[0041] In the present invention, in the above-mentioned component A, the filler is not particularly limited and can be barium sulfate, talc, kaolin, wollastonite, heavy calcium carbonate, hard calcium carbonate, titanium dioxide, etc.; the auxiliary agent can be a leveling agent, a wetting agent, a defoaming agent, a thixotropic agent, an anti-settling agent, a dispersant, a thickener, an anti-ultraviolet agent, an anti-yellowing agent, an antioxidant, etc.; the pigment can be an inorganic pigment or an organic pigment.

[0042] In a preferred embodiment of the present invention, the weight content of the aspartic acid ester resin is 23-40%. For example, the weight content of the aspartic acid ester resin can be any value of 23%, 25%, 27%, 28%, 30%, 32%, 33%, 35%, 37%, 38%, 40%, etc., without particular limitation.

[0043] In a preferred embodiment of the present invention, the weight content of the copolymer is 5-20%. For example, the weight content of the copolymer can be any value of 5%, 7%, 8%, 10%, 12%, 14%, 15%, 16%, 18%, 20%, etc., without special limitation.

[0044] In the present invention, there is no particular limitation on the preparation method of component A, for example, the raw material components can be mixed and dispersed evenly.

[0045] In a preferred embodiment of the present invention, the weight percentage of the isocyanate curing agent in component B is not less than 80%. If the weight percentage of the isocyanate curing agent in component B is too low, the performance of the asparagine polyurea coating will be affected. For example, the weight percentage of the isocyanate curing agent in component B can be 80%, 82%, 85%, 88%, 90%, 92%, 95%, 96%, 97%, etc., and the remainder can be a dehydrating agent, a solvent, etc. as needed.

[0046] In the present invention, there is no particular limitation on the preparation method of component B, for example, the raw material components may be mixed and dispersed uniformly.

[0047] Before use, component A and component B are mixed evenly according to a certain proportion to obtain the asparagus polyurea coating composition of the present invention.

[0048] The technical solution of the present invention is further described and illustrated according to various embodiments below. Unless otherwise specified, the parts described in the following embodiments are parts by weight.

[0049] Example 1-4 Preparation of copolymer

[0050] Example 1

[0051] The copolymer raw material components consist of 13 parts of diethyl maleate, 15 parts of styrene and 72 parts of acrylate monomers (composed of methyl methacrylate, isooctyl methacrylate and octadecyl methacrylate in a molar ratio of 1:2:2), and also contain 100 parts of butyl acetate and 1.5 parts of benzoyl peroxide.

[0052] Add 90 parts of butyl acetate and 1.2 parts of benzoyl peroxide into the reaction container, stir evenly, pass nitrogen protection and raise the temperature to 120°C, add dropwise a mixture of diethyl maleate, styrene and acrylate monomers, react at a constant temperature for 3 hours, add the remaining butyl acetate and benzoyl peroxide, continue the reaction for 2 hours, and cool down to obtain a copolymer solution.

[0053] Example 2

[0054] The difference between this embodiment and embodiment 1 is that in embodiment 1, diethyl maleate is adjusted from 13 parts to 22 parts, and acrylate monomer is adjusted from 72 parts to 63 parts. The other steps remain unchanged.

[0055] Example 3

[0056] The difference between this embodiment and embodiment 1 is that in embodiment 1, the amount of diethyl maleate is adjusted from 13 parts to 30 parts, and the amount of acrylate monomer is adjusted from 72 parts to 55 parts. The remaining steps remain unchanged.

[0057] Example 4

[0058] The copolymer raw material components consist of 18 parts of dibutyl maleate, 20 parts of styrene and 62 parts of acrylate monomers (methyl methacrylate, butyl methacrylate and dodecyl methacrylate in a molar ratio of 1:1:2), and also contain 100 parts of butyl acetate and 1.5 parts of benzoyl peroxide.

[0059] Add 90 parts of butyl acetate and 1.2 parts of benzoyl peroxide into the reaction container, stir evenly, pass nitrogen protection and raise the temperature to 120°C, add dropwise a mixture of dibutyl maleate, styrene and acrylate monomers, react at a constant temperature for 3 hours after the addition is completed, add the remaining butyl acetate and benzoyl peroxide, continue the reaction for 3 hours, cool down, and obtain a copolymer solution.

[0060] Comparative Example 1

[0061] The difference between this comparative example and Example 1 is that in Example 1, diethyl maleate is replaced by an equal weight of acrylate monomer, that is, diethyl maleate is not added in this comparative example. The remaining steps remain unchanged.

[0062] Comparative Example 2

[0063] The difference between this comparative example and Example 1 is that in Example 1, the acrylate monomer is adjusted to an acrylate monomer composed of methyl methacrylate, hydroxyethyl methacrylate, isooctyl methacrylate and octadecyl methacrylate in a molar ratio of 1:1:1:2. The other steps remain unchanged.

[0064] Example 5-12 Preparation of Asparagus polyurea coating

[0065] The component A of the aspartame polyurea coating compositions of Examples 5-8 and Comparative Examples 3-5 are shown in Table 1 below.

[0066] Table 1A Component composition / part

[0067]

[0068]

[0069] The mixing additives are BYK-2013:BYK-054:BYK-354=1:0.3:0.3 (weight ratio).

[0070] Component B consists of 90 parts of Wanhua HT-600, 0.3 parts of TI water absorption stabilizer, 7.5 parts of butyl acetate and 2.2 parts of PMA.

[0071] The molar ratio of NH groups in component A to NCO groups in component B is 1:1.05.

[0072] Performance testing methods

[0073] Compatibility: Mix 30 parts of F420 resin and 14 parts of the copolymer to be tested, stir evenly, and observe the appearance of the mixture, which may be transparent, translucent or opaque. Transparency indicates good compatibility, while translucent and opaque indicate poor compatibility. The worse the transparency, the lower the compatibility.

[0074] Coating viscosity: measured according to the method of GB / T 1723-1993, coating-4 cup method.

[0075] Applicable period: Determined according to the method of GB / T31416-2015.

[0076] Surface drying time and actual drying time: determined according to the method of GB / T 1728-2020.

[0077] Gloss: measured according to the method of GB / T 9754-2007, with a test angle of 60°.

[0078] Cross-cut test: Determined according to the method of BG / T 9286-2021, with grade 0 being the best and grade 5 being the worst.

[0079] Flexibility: measured according to the method of GB / T 1731-2020.

[0080] Hardness: measured according to the method of GB / T 6739-1996.

[0081] Impact strength: measured according to the method of GB / T1732-2020.

[0082] The results are shown in Table 2 below.

[0083] Table 2

[0084]

[0085]

[0086] It can be seen from the data results in Table 2 that in the asparagine polyurea coating with F420 resin as the main resin, replacing part of the F420 resin with the copolymer of the present invention can significantly extend the application period, and the surface drying time and the actual drying time do not change much. In addition, compared with the use of all F420 resin, the changes in other properties are also relatively small.

[0087] Example 9

[0088] In this embodiment, component A is composed of 42 parts of F420 resin, 3 parts of the copolymer of Example 2, 1 part of butyl acetate, 3 parts of PMA, 20 parts of kaolin, 25 parts of titanium dioxide, 1.4 parts of phthalocyanine blue, 3 parts of 3A molecular sieve and 1.6 parts of the mixing aid in Example 5.

[0089] Component B consists of 90 parts of Wanhua HT-600, 0.3 parts of TI water absorption stabilizer, 7.5 parts of butyl acetate and 2.2 parts of PMA.

[0090] The molar ratio of NH groups in component A to NCO groups in component B is 1:1.08.

[0091] Example 10

[0092] The difference between this embodiment and embodiment 9 is that in embodiment 9, the F420 resin is adjusted from 42 parts to 40 parts, and the copolymer is adjusted from 3 parts to 5 parts. The other steps remain unchanged.

[0093] Embodiment 11

[0094] The difference between this embodiment and embodiment 9 is that in embodiment 9, the F420 resin is adjusted from 42 parts to 25 parts, and the copolymer is adjusted from 3 parts to 20 parts. The other steps remain unchanged.

[0095] Example 12

[0096] The difference between this embodiment and embodiment 9 is that in embodiment 9, the F420 resin is adjusted from 42 parts to 20 parts, and the copolymer is adjusted from 3 parts to 25 parts. The other steps remain unchanged.

[0097] Comparative Example 6

[0098] The difference between this comparative example and Example 9 is that in Example 9, the F420 resin is adjusted from 42 parts to 15 parts, and the copolymer is adjusted from 3 parts to 30 parts. The other steps remain unchanged.

[0099] The performance test results are shown in Table 3 below.

[0100] Table 3

[0101] performance Example 9 Example 10 Embodiment 11 Example 12 Comparative Example 6 Compatibility transparent transparent transparent transparent transparent Viscosity / Coating-4S 93 84 68 65 60 Applicable period / min 62 69 102 116 127 Surface drying time / min 18 20 23 25 32 Drying time / min 60 62 64 70 83 Glossiness 90.7 92.8 92.1 91.7 90.2 Scratching test / 1mm Level 1 Level 1 Level 1 Level 2 Level 3 Flexibility / mm 1 1 1 1 2 Pencil hardness H H F HB HB Impact strength / cm 50 50 50 50 50

[0102] From the data results in Table 3 above, it can be seen that in the asparagus polyurea coating of the present invention, as the amount of copolymer replacing F420 resin increases, within 25 parts of the copolymer, the applicable period is significantly extended, but the surface dry time and the actual dry time do not change much, and other properties do not change much. When the copolymer exceeds 25 parts, although the applicable period is also extended accordingly, the surface dry time and the actual dry time are extended more, and the properties such as adhesion, hardness, and flexibility are significantly deteriorated.

[0103] As described above, the basic principles, main features and advantages of the present invention are shown and described. Those skilled in the art should understand that the present invention is not limited by the above embodiments, which are only preferred embodiments of the present invention and cannot be used to limit the scope of the present invention. That is, equivalent changes and modifications made according to the scope of the present invention and the content of the specification should still be within the scope of the present invention. The scope of protection required by the present invention is defined by the attached claims and their equivalents.

Claims

1. A copolymer, characterized in that The raw material components contain 13-30% dialkyl maleate based on 100% by weight, and the remainder is one or a combination of two or more of acrylic acid ester monomers and styrene monomers; The acrylic ester monomer and the styrene monomer are respectively inert to react with isocyanate groups at 60°C.

2. The copolymer according to claim 1, characterized in that The general formula of the dialkyl maleate is R 1 OOCCH=CHCOOR 2 , where R 1 and R 2 Independently selected from C1-C8 alkyl.

3. The copolymer according to claim 1, characterized in that The general formula of the acrylic acid ester monomer is CH2=C(R 3 )COOR 4 , where R 3 is selected from H or C1-C4 alkyl, R 4 Selected from C1-C18 alkyl or C2-C18 substituted alkyl.

4. The copolymer according to claim 3, characterized in that The R 4 The molar proportion of C4-C18 alkyl is not less than 10%.

5. The copolymer according to claim 1, characterized in that The R 4 The molar proportion of the methyl group is not less than 20%.

6. The copolymer according to claim 1, characterized in that The styrene monomer is selected from one or a combination of two or more of styrene, 3-methylstyrene and 4-methylstyrene.

7. An aspartame polyurea coating composition, characterized in that It is composed of component A and component B; The component A comprises 20-50% aspartic acid ester resin and 3-25% of the copolymer according to any one of claims 1 to 6, and the balance is one or a combination of two or more of fillers, additives and pigments, based on 100% by weight; The B component comprises an isocyanate curing agent; The molar ratio of the NH groups in the A component to the NCO groups in the B component is 1:0.95-1.

2.

8. The asparagine polyurea coating composition according to claim 7, characterized in that: The weight content of the aspartic acid ester resin is 23-40%.

9. The asparagine polyurea coating composition according to claim 7, characterized in that: The weight content of the copolymer is 5-20%.

10. The asparagine polyurea coating composition according to claim 7, characterized in that: The weight percentage of the isocyanate curing agent in the B component is not less than 80%.

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