Modified copolymerized acrylic resin, preparation method thereof, coating and coating product

Abstract

The present invention provides a modified copolymerized acrylic resin, a preparation method thereof, a coating, and a coating product. The raw materials for preparing the modified copolymerized acrylic resin include: a modified polymer, a comonomer, a hydroxyl-functional monomer, an initiator, and a first solvent; the comonomer includes an acrylic monomer; the raw materials for preparing the modified polymer include: a polyamide, an aliphatic diol, an aliphatic polyol A, maleic anhydride, a dibasic acid, and a second solvent; one molecule of the aliphatic polyol A contains three or more hydroxyl groups; the raw materials for preparing the polyamide include: an alicyclic diamine, a cyclic anhydride, a functional additive, and a third solvent; the cyclic anhydride contains at least one of a cycloalkyl group and an aromatic group. When used to prepare a coating, the modified copolymerized acrylic resin can increase the hardness of the coating after film formation, thereby improving wear resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and in particular to a modified copolymerized acrylic resin and a preparation method thereof, a coating and a coating product. Background Art

[0002] With the development of the economy, cars have entered thousands of households, and the automobile industry has become a pillar industry of the national economy, with its status becoming increasingly important. The automobile painting industry has also developed rapidly.

[0003] As an important outdoor transportation tool, cars inevitably need to be cleaned during use. During the cleaning process, the paint film of the car will inevitably be rubbed and cleaned. However, the paint film formed by traditional car paints often has tiny scratches after repeated cleaning, which reduces the appearance of the car. More importantly, the presence of scratches will cause the protective performance of the paint film on car parts to decline, affecting the service life of the car.

[0004] Therefore, traditional technologies still need to be improved. Summary of the Invention

[0005] Based on this, the present invention provides a modified copolymer acrylic resin and its preparation method, coating and coating product, aiming to improve the wear resistance of the coating after film formation.

[0006] The technical solutions of the present invention are as follows.

[0007] In one aspect, the present invention provides a modified copolymerized acrylic resin, wherein the raw materials for preparing the modified copolymerized acrylic resin include: a modified polymer, a comonomer, a hydroxyl functional monomer, an initiator, and a first solvent; the comonomer includes an acrylic monomer;

[0008] The raw materials for preparing the modified polymer include: polyamide, aliphatic diol, aliphatic polyol A, maleic anhydride, dibasic acid and a second solvent; one molecule of the aliphatic polyol A contains three or more hydroxyl groups;

[0009] The raw materials for preparing the polyamide include: alicyclic diamine, cyclic acid anhydride, functional auxiliary agent and a third solvent, and the cyclic acid anhydride contains at least one structure of a cycloalkyl group and an aromatic group.

[0010] The raw materials of the modified copolymer acrylic resin include specific substances, among which alicyclic diamines and cyclic anhydrides are used as raw materials to prepare polyamide, and amide bonds are introduced to improve the wear resistance of the resin. Furthermore, the polyamide is used as the raw material for condensation polymerization with aliphatic diols, aliphatic polyols A, maleic anhydride, and dibasic acid. On the one hand, the aliphatic diols and aliphatic polyols A will esterify with the carboxylic acids on the polyamide, and on the other hand, the aliphatic diols, aliphatic polyols A, maleic anhydride, and dibasic acid are polarly condensed to introduce polyester segments for modification. In addition, one molecule of aliphatic polyol A contains three or more hydroxyl groups, which can increase the branching degree of the modified polymer and thus improve the numerical wear resistance. Further, the modified polymer, comonomer, and hydroxyl-functional monomer are polymerized under the action of an initiator to introduce propylene-based polymer segments into the modified polymer. At the same time, hydroxyl functional groups are introduced through the hydroxyl-functional monomer to provide crosslinking sites and improve the crosslinking degree of the resin after curing. In this way, the coordination of the components greatly improves the hardness of the resin after film formation, thereby improving the wear resistance.

[0011] In some embodiments, the modified copolymerized acrylic resin satisfies at least one of the following conditions (1) to (2):

[0012] (1) The raw materials for preparing the modified copolymerized acrylic resin include: 31% to 42% of the modified polymer, 13% to 18.5% of the comonomer, 19% to 27% of the hydroxyl functional monomer, 0.5% to 1.5% of the initiator, and 14% to 39% of the first solvent;

[0013] By further adjusting the ratio of each raw material, the hardness of the resin film can be further improved.

[0014] (2) The modified copolymerized acrylic resin is a multi-branched polymer.

[0015] In some embodiments, the comonomer includes a first comonomer and a second comonomer, wherein the first comonomer is represented by formula (1):

[0016]

[0017] R1 is selected from alkanes having 1 to 15 carbon atoms;

[0018] Optionally, the first comonomer comprises at least one of acrylic acid and methacrylic acid;

[0019] The second comonomer includes at least one of a compound represented by formula (2) and a vinyl monomer containing an aromatic group:

[0020]

[0021] wherein R3 is selected from any one of a chain alkyl group having 1 to 15 carbon atoms and a cycloalkyl group having 3 to 15 carbon atoms, and R2 is selected from a chain alkyl group having 1 to 5 carbon atoms;

[0022] Optionally, the compound represented by formula (2) includes at least one of methyl acrylate, n-butyl acrylate, isobutyl acrylate, isobornyl acrylate, isooctyl acrylate, dodecyl acrylate, methyl methacrylate, n-butyl methacrylate, isobutyl acrylate, isobornyl methacrylate, isooctyl methacrylate, and dodecyl methacrylate;

[0023] Optionally, the aromatic group-containing vinyl monomer includes styrene.

[0024] In some embodiments, based on the total mass of the raw materials for preparing the modified copolymerized acrylic resin, the mass proportion of the first comonomer is 0.5% to 1%, and the mass proportion of the second comonomer is 12.5% ​​to 17.5%.

[0025] In some embodiments, the modified polymer satisfies at least one of the following conditions (3) to (4):

[0026] (3) Based on the total mass of the raw materials for preparing the modified copolymerized acrylic resin, the mass proportion of the polyamide is 17% to 22%, the mass proportion of the aliphatic diol is 1% to 6%, the mass proportion of the aliphatic polyol A is 5.5% to 9.5%, the mass proportion of the dibasic acid is 5.5% to 12%, the mass proportion of the maleic anhydride is 0.2% to 0.5%, and the mass proportion of the second solvent is 2% to 3%;

[0027] (4) The modified polymer is a branched copolymer.

[0028] In some embodiments, based on the total mass of the raw materials for preparing the modified copolymer acrylic resin, the mass proportion of the alicyclic diamine is 2% to 7.5%, the mass proportion of the cyclic anhydride is 5.3% to 14.5%, the mass proportion of the functional additive is 0.01% to 0.1%, and the mass proportion of the third solvent is 2% to 7%.

[0029] In some embodiments, the hydroxyl functional monomer is as shown in formula (3):

[0030]

[0031] wherein R4 is selected from a chain alkyl group having 1 to 5 carbon atoms, and R5 is selected from a chain alkyl group having 1 to 5 carbon atoms;

[0032] Optionally, the hydroxyl functional monomer includes at least one of hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, hydroxybutyl acrylate and hydroxybutyl methacrylate.

[0033] In some embodiments, the initiator comprises a peroxide compound initiator;

[0034] The first solvent includes at least one of an aromatic hydrocarbon solvent and an alcohol ether solvent.

[0035] In some embodiments, the raw materials for preparing the modified polymer meet at least one of the following conditions (5) to (7):

[0036] (5) The aliphatic diol includes at least one of 2,2-dimethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, and 2-ethyl-2-butyl-1,3-propanediol;

[0037] Optionally, the aliphatic diol includes at least one of 2,2-dimethyl-1,3-propanediol and 1,6-hexanediol;

[0038] (6) the aliphatic polyol A comprises at least one of trimethylolpropane and pentaerythritol;

[0039] (7) The dibasic acid includes at least one of an aromatic dibasic acid and an aliphatic dibasic acid;

[0040] Optionally, the dibasic acid includes at least one of isophthalic acid, adipic acid, and 1,4-cyclohexanedicarboxylic acid.

[0041] In some embodiments, the raw materials for preparing the polyamide meet at least one of the following conditions (8) to (10):

[0042] (8) The number of ring atoms of the alicyclic diamine is 4 to 6;

[0043] Optionally, the alicyclic diamine includes at least one of 1,2-cyclobutanediamine, 1,3-cyclobutanediamine, 1,2-cyclopentanediamine, 1,3-cyclopentanediamine, 1,2-cyclohexanediamine, 1,3-cyclohexanediamine, 1,4-cyclohexanediamine and isophoronediamine;

[0044] (9) The cyclic acid anhydride includes at least one of phthalic anhydride, hexahydrophthalic anhydride and methylhexahydrophthalic anhydride;

[0045] (10) The functional auxiliary agent includes an antioxidant.

[0046] In some embodiments, the modified copolymer acrylic resin has a solid content of 60 wt% to 80 wt%, a hydroxyl value of 185 mgKOH / g to 240 mgKOH / g, and a weight average molecular weight of 6,000 to 18,000.

[0047] Another aspect of the present invention provides a method for preparing the modified copolymerized acrylic resin, comprising the following steps:

[0048] Mixing the cyclic anhydride, the auxiliary agent, and a portion of the third solvent to prepare a first mixed solution;

[0049] mixing the alicyclic diamine and the remaining portion of the third solvent to prepare a second mixed solution;

[0050] dropping the second mixed solution into the first mixed solution to carry out a ring-opening addition polymerization reaction to prepare the polyamide;

[0051] The polyamide, the aliphatic diol, the aliphatic polyol A, the maleic anhydride and the dibasic acid are mixed for polycondensation, and the second solvent is added for azeotropic dehydration to prepare the modified polymer;

[0052] mixing the modified polymer and the first portion of the first solvent to prepare a third mixed solution;

[0053] mixing the comonomer, the hydroxyl functional monomer, and a second portion of the first solvent to prepare a fourth mixed solution;

[0054] mixing a portion of the initiator and a third portion of the first solvent to prepare a fifth mixed solution;

[0055] mixing the remaining portion of the initiator and the fourth portion of the first solvent to prepare a sixth mixed solution;

[0056] The fourth mixed liquid and the fifth mixed liquid are dropped into the third mixed liquid to carry out polymerization reaction, and then the sixth mixed liquid is added for aging treatment, and finally the remaining first solvent is added for dilution to prepare the modified copolymer acrylic resin.

[0057] In the above preparation method, alicyclic diamine and cyclic anhydride are first used as raw materials to prepare polyamide through a ring-opening addition polymerization reaction, and amide bonds are introduced to improve the wear resistance of the resin. Furthermore, polyamide is used as raw material and subjected to condensation polymerization with aliphatic diol, aliphatic polyol A, maleic anhydride, and dibasic acid. On the one hand, the aliphatic diol and aliphatic polyol A will esterify with the carboxylic acid on the polyamide to modify it. On the other hand, the aliphatic diol, aliphatic polyol A, maleic anhydride, and dibasic acid are polarly condensed to introduce polyester segments for modification. In addition, one molecule of aliphatic polyol A contains three or more hydroxyl groups, which can increase the branching degree of the modified polymer and thus improve the numerical wear resistance. Further, the modified polymer, comonomer, and hydroxyl-functional monomer are polymerized under the action of an initiator to introduce propylene-based polymer segments into the modified polymer. At the same time, hydroxyl functional groups are introduced through the hydroxyl-functional monomer to provide crosslinking sites and improve the crosslinking degree of the resin. In this way, the coordination of the components greatly improves the hardness of the resin after film formation, thereby improving the wear resistance.

[0058] In some embodiments, the ring-opening addition polymerization reaction satisfies at least one of the following conditions (11) to (12);

[0059] (11) The temperature of the ring-opening addition polymerization is 50° C. to 80° C.;

[0060] (12) during the preparation of the polyamide, when the acid value of the reaction system is 230 mg KOH / g to 280 mg KOH / g, stopping the ring-opening addition polymerization;

[0061] The polycondensation reaction satisfies at least one of the following conditions (13) to (14);

[0062] (13) The temperature of the polycondensation reaction is 160±2°C to 230±2°C;

[0063] (14) during the preparation of the modified polymer, when the acid value of the reaction system is 7 mg KOH / g to 9 mg KOH / g, stopping the polycondensation reaction;

[0064] The polymerization reaction satisfies at least one of the following conditions (15) to (16);

[0065] (15) The polymerization reaction temperature is 130° C. to 150° C. and the reaction time is 3.5 h to 6 h;

[0066] (16) The temperature of the aging treatment is 130°C to 150°C, and the time is 0.5h to 1.5h.

[0067] In another aspect of the present application, a coating is provided, wherein the coating contains the above-mentioned modified copolymerized acrylic resin.

[0068] The above-mentioned coating comprises the above-mentioned modified copolymerized acrylic resin, which has high hardness and can improve the wear resistance of the coating film formed by the coating.

[0069] In another aspect of the present application, a coating product is provided, wherein the coating product comprises a coating film formed by the coating material as described above. DETAILED DESCRIPTION

[0070] To facilitate understanding of the present invention, the present invention will be described more fully below, along with preferred embodiments thereof. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present invention.

[0071] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0072] The term "acrylic monomers" refers to monomers used to prepare acrylic resins, mainly acrylic acid and its homologues, acrylates and their homologues.

[0073] The term "aliphatic" is also called an open-chain compound, in which the carbon atoms in the molecule are connected in a chain, and is divided into saturated aliphatic compounds and unsaturated aliphatic compounds.

[0074] The term "alicyclic" refers to a molecule containing a carbon ring composed of 3 or more carbon atoms.

[0075] In the present invention, the term "alkyl" refers to a group formed when an alkane loses a hydrogen, for example, methane loses a hydrogen to form a methyl group; the term "chain alkyl" refers to a group formed when an alkane loses a hydrogen, in which the carbon atoms are all connected by carbon-carbon single bonds and do not form a ring, and the remaining valence bonds are all bound to hydrogen, including straight-chain alkyl and branched-chain alkyl; the term "cycloalkyl" refers to a group formed when a cycloalkane with at least 3 or more carbon atoms connected and forming a ring loses a hydrogen.

[0076] In the present invention, the number of carbon atoms in the "alkyl group having 1 to 15 carbon atoms" can be any integer from 1 to 15, including 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, 12, 13, 14 or 15, and refers to a group formed by losing one hydrogen from an alkane containing 1 to 15 carbon atoms. Specific examples include C1 alkane, C2 alkane, C3 alkane, C4 alkane, C5 alkane, C6 alkane, C7 alkane, C8 alkane, C9 alkane or C10 alkane, C11 alkane, C12 alkane, C13 alkane or C14 alkane. The group formed when a C14 chain alkane loses one hydrogen, and non-limiting examples of "C1-15 alkanes" include methane, ethane, n-propane, isopropane, n-butane, isobutane, 2-ethylbutane, 3,3-dimethylbutane, n-pentane, isopentane, neopentane, 1-methylpentane, 3-methylpentane, 2-ethylpentane, 4-methyl-2-pentane, n-hexane, 1-methylhexane, 2-ethylhexane, 2-butylhexane, n-heptane, 1-methylheptane, 2,2-dimethylheptane, 2-ethylheptane, n-octane, n-nonane, n-decane, and dodecane.

[0077] Similarly, non-limiting examples of "alkyl radicals having 1 to 5 carbon atoms" include radicals formed by losing one hydrogen atom from the aforementioned C1-5 alkanes.

[0078] Similarly, non-limiting examples of “any one of the cycloalkyl groups having 3 to 15 carbon atoms” include groups formed by losing one hydrogen atom from the above-mentioned C3 to 15 cycloalkanes.

[0079] To summarize the above background, the paint films formed by traditional automotive coatings have limited wear resistance, and the traditional preparation process focuses on designing highly elastic coatings to improve wear resistance.

[0080] However, the technical personnel of this application have found that although the high-elasticity coating can undergo elastic deformation when subjected to abrasion stress and the coating will recover after the abrasion stress disappears, the hardness of the traditional high-elasticity coating is slightly low. When subjected to external forces higher than the elastic deformation stress, the entire resin structure may be destroyed. At the same time, the low coating hardness will cause other problems, such as unqualified pencil hardness, resulting in very limited improvement in wear resistance.

[0081] Therefore, the technical personnel of this application broke the constraints of the existing technology and creatively started from improving the hardness of the coating. After a large number of creative experimental explorations, they obtained the modified copolymer acrylic resin in this application.

[0082] One embodiment of the present invention provides a modified copolymerized acrylic resin, wherein the raw materials for preparing the modified copolymerized acrylic resin include: a modified polymer, a comonomer, a hydroxyl functional monomer, an initiator, and a first solvent; the comonomer includes an acrylic monomer;

[0083] The raw materials for preparing the modified polymer include: polyamide, aliphatic diol, aliphatic polyol A, maleic anhydride, dibasic acid and a second solvent; one molecule of aliphatic polyol A contains three or more hydroxyl groups;

[0084] The raw materials for preparing the polyamide include: alicyclic diamine, cyclic acid anhydride, functional auxiliary agent and a third solvent. The cyclic acid anhydride contains at least one structure of a cycloalkyl group and an aromatic group.

[0085] The raw materials of the modified copolymer acrylic resin include specific substances, among which alicyclic diamines and cyclic anhydrides are used as raw materials to prepare polyamide, and amide bonds are introduced to improve the wear resistance of the resin. Furthermore, the polyamide is used as the raw material for condensation polymerization with aliphatic diols, aliphatic polyols A, maleic anhydride, and dibasic acid. On the one hand, the aliphatic diols and aliphatic polyols A will esterify with the carboxylic acids on the polyamide, and on the other hand, the aliphatic diols, aliphatic polyols A, maleic anhydride, and dibasic acid are polarly condensed to introduce polyester segments for modification. In addition, one molecule of aliphatic polyol A contains three or more hydroxyl groups, which can increase the branching degree of the modified polymer and thus improve the numerical wear resistance. Further, the modified polymer, comonomer, and hydroxyl-functional monomer are polymerized under the action of an initiator to introduce propylene-based polymer segments into the modified polymer. At the same time, hydroxyl functional groups are introduced through the hydroxyl-functional monomer to provide crosslinking sites and improve the crosslinking degree of the resin after curing. In this way, the coordination of the components greatly improves the hardness of the resin after film formation, thereby improving the wear resistance.

[0086] In some embodiments, the raw materials for preparing the modified copolymerized acrylic resin include: 31% to 42% modified polymer, 13% to 18.5% comonomer, 19% to 27% hydroxyl functional monomer, 0.5% to 1.5% initiator and 14% to 39% of the first solvent.

[0087] By further adjusting the ratio of each raw material, the hardness of the resin film can be further improved.

[0088] It should be noted that when a numerical range is disclosed herein, the above range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values.

[0089] For example, "31% to 42%" includes but is not limited to: 31%, 31.46%, 32%, 32.5%, 33%, 33.5%, 34%, 34.5%, 35%, 35.5%, 36%, 36.1%, 36.2%, 36.3%, 36.4%, 36.5%, 36.6%, 36.64%, 36.65%, 36.7%, 36.8%, 36.9%, 37%, 37.1%, 37.2%, 37.3%, 37.4%, 37.5%, 37.6%, 37.7%, 37.8%, 37.9%, 38%, 38.1%, 38.2%, 38.3%, 38.4% , 38.5%, 38.6%, 38.7%, 38.8%, 38.9%, 39%, 39.1%, 39.16%, 39.2%, 39.3%, 39.4%, 39.5%, 39.6%, 39.7%, 39.8%, 39.9%, 40%, 40.1%, 40.2%, 40.3%, 40.4%, 40.5%, 40.6%, 40.7%, 40.8%, 40.9%, 41%, 41.1%, 41.2%, 41.3%, 41.4%, 41.5%, 41.6%, 41.7%, 41.8%, 41.9% and 42%, or a range consisting of any two values.

[0090] For example, "13% to 18.5%" includes but is not limited to: 13%, 13.1%, 13.2%, 13.3%, 13.35%, 13.37%, 13.4%, 13.5%, 13.6%, 13.7%, 13.8%, 13.9%, 14%, 14.1%, 14.2%, 14.3%, 14.4%, 14.5%, 14.6%, 14.7%, 14.8%, 14.9%, 15%, 15.1%, 15.2%, 15.3%, 15.4%, 15.48%, 15.5%, 15.57%, or a range consisting of any two values.

[0091] For example, "19%-27%" includes but is not limited to: 19%, 19.2%, 19.29%, 20%, 20.05%, 20.07%, 20.5%, 21%, 22%, 22.47%, 23%, 24%, 25%, 26.59%, 25.64%, 26%, 27%, or a range consisting of any two values.

[0092] For example, "0.5% to 1.5%" includes but is not limited to: 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 0.98%, 1%, 1.1%, 1.14%, 1.2%, 1.3%, 1.4%, 1.42%, 1.5%, or a range consisting of any two values.

[0093] For example, "14% to 39%" includes but is not limited to: 14%, 14.1%, 14.2%, 14.3%, 14.4%, 14.5%, 14.6%, 14.7%, 14.8%, 14.9%, 15%, 15%, 15.1%, 15.2%, 15.3%, 15.4%, 15.48%, 15.5%, 15.57%, 15.6%, 15.7%, 15.8%, 15.9%, 16%, 16.1%, 16.2%, 16.3%, 16.4%, 16.5%, 16.6%, 16.7%, 16.8%, 16.9%, 17%. %, 6.9%, 17%, 17.1%, 17.11%, 17.2%, 17.3%, 17.4%, 17.5%, 17.6%, 17.7%, 17.78%, 17.8%, 17.9%, 18%, 18.1%, 18.2%, 18.3%, 18.4%, 18.5%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, or a range consisting of any two values.

[0094] In some embodiments, the modified copolymerized acrylic resin is a multi-branched polymer, specifically, including two or more branches.

[0095] In some embodiments, the comonomer includes a first comonomer and a second comonomer, and the first comonomer is represented by formula (1):

[0096]

[0097] R1 is selected from alkanes having 1 to 15 carbon atoms.

[0098] Optionally, the first comonomer comprises at least one of acrylic acid and methacrylic acid;

[0099] The second comonomer includes at least one of a compound represented by formula (2) and a vinyl monomer containing an aromatic group:

[0100]

[0101] Here, R3 is selected from any one of a chain alkyl group having 1 to 15 carbon atoms and a cycloalkyl group having 3 to 15 carbon atoms, and R2 is selected from a chain alkyl group having 1 to 5 carbon atoms.

[0102] In some embodiments, the compound represented by formula (2) includes at least one of methyl acrylate, n-butyl acrylate, isobutyl acrylate, isobornyl acrylate, isooctyl acrylate, dodecyl acrylate, methyl methacrylate, n-butyl methacrylate, isobutyl acrylate, isobornyl methacrylate, isooctyl methacrylate, and dodecyl methacrylate.

[0103] In some embodiments, the compound represented by formula (2) includes at least one of isooctyl acrylate (2-EHA), dodecyl acrylate (SLA), isooctyl methacrylate (2-EHMA), and dodecyl methacrylate (SLMA).

[0104] Alternatively, the aromatic group-containing vinyl monomer includes styrene.

[0105] In some embodiments, based on the total mass of the raw materials for preparing the modified copolymerized acrylic resin, the mass proportion of the first comonomer is 0.5% to 1%, and the mass proportion of the second comonomer is 12.5% ​​to 17.5%.

[0106] By regulating the type and quality of comonomers, the performance of the resin can be further improved.

[0107] “0.5% to 1%” includes but is not limited to: 0.5%, 0.59%, 0.6%, 0.69%, 0.7%, 0.74%, 0.79%, 0.8%, 0.9%, 0.98%, 1%, or a range consisting of any two values.

[0108] “12.5% ​​to 17.5%” includes but is not limited to: 12.5%, 12.78%, 13%, 13.32%, 14%, 14.1%, 14.2%, 14.3%, 14.4%, 14.5%, 14.6%, 14.68%, 14.7%, 14.8%, 14.88%, 14.9%, 15%, 15%, 15.1%, 15.2%, 15.28%, 15.3%, 15.4%, 15. 48%, 15.5%, 15.57%, 15.6%, 15.7%, 15.8%, 15.9%, 16%, 16.1%, 16.2%, 16.3%, 16.4%, 16.5%, 16.6%, 16.7%, 16.8%, 16.9%, 16.99%, 17%, 17.1%, 17.2%, 17.3%, 17.31%, 17.4%, 17.5%, or a range consisting of any two values.

[0109] In some embodiments, the hydroxyl functional monomer is represented by formula (3):

[0110]

[0111] Among them, R4 is selected from a chain alkyl group having 1 to 5 carbon atoms, and R5 is selected from a chain alkyl group having 1 to 5 carbon atoms.

[0112] In some embodiments, R4 is selected from a chain alkyl group having 1 to 4 carbon atoms, and R5 is selected from a chain alkyl group having 1 to 2 carbon atoms.

[0113] Optionally, the hydroxyl functional monomer includes at least one of hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, hydroxybutyl acrylate and hydroxybutyl methacrylate.

[0114] In some embodiments, the hydroxyl functional monomer includes at least one of hydroxyethyl acrylate, hydroxypropyl acrylate (HPA), 2-hydroxyethyl methacrylate (HEMA), and 2-hydroxypropyl methacrylate.

[0115] In some embodiments, the initiator comprises a peroxide compound initiator.

[0116] In some embodiments, the peroxide initiator includes at least one of di-tert-butyl hydroperoxide (DTBP) and a peroxyester-based peroxide.

[0117] Specifically, the peroxide initiator includes one or more of di-tert-amyl hydroperoxide (DTAP) and Perbutylo.

[0118] In some embodiments, the first solvent includes at least one of an aromatic hydrocarbon solvent and an alcohol ether solvent.

[0119] Specifically, the aromatic hydrocarbon solvent is one or more of toluene and xylene, and specifically, the aromatic hydrocarbon solvent is xylene; the alcohol ether solvent includes propylene glycol methyl ether acetate.

[0120] In some embodiments, based on the total mass of the raw materials for preparing the modified copolymerized acrylic resin, the mass of the polyamide accounts for 17% to 22%, the mass of the aliphatic diol accounts for 1% to 6%, the mass of the aliphatic polyol A accounts for 5.5% to 9.5%, the mass of the dibasic acid accounts for 5.5% to 12%, the mass of maleic anhydride accounts for 0.2% to 0.5%, and the mass of the second solvent accounts for 2% to 3%.

[0121] The performance of the modified polymer can be further improved by further adjusting the ratio of each preparation raw material.

[0122] In some embodiments, based on the total mass of the raw materials for preparing the modified copolymerized acrylic resin, the mass proportion of polyamide is 17% to 22%, the mass proportion of aliphatic diol is 2% to 6%, the mass proportion of aliphatic polyol A is 5.5% to 7.5%, the mass proportion of dibasic acid is 5.5% to 8%, and the mass proportion of maleic anhydride is 0.2% to 0.4%.

[0123] In some embodiments, the modified polymer is a branched copolymer.

[0124] Specifically, the branched copolymer includes one or more branches.

[0125] In some embodiments, the aliphatic diol includes at least one of 2,2-dimethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, and 2-ethyl-2-butyl-1,3-propanediol.

[0126] Alternatively, the aliphatic diol includes at least one of 2,2-dimethyl-1,3-propanediol and 1,6-hexanediol.

[0127] In some embodiments, the aliphatic polyol A includes at least one of trimethylolpropane and pentaerythritol.

[0128] In some embodiments, the dibasic acid comprises at least one of an aromatic dibasic acid, an alicyclic dibasic acid, and an aliphatic dibasic acid.

[0129] In some embodiments, the dibasic acid includes at least one aliphatic dibasic acid.

[0130] Optionally, the dibasic acid includes at least one of isophthalic acid, adipic acid, and 1,4-cyclohexanedicarboxylic acid.

[0131] Optionally, the above-mentioned dibasic acid is adipic acid.

[0132] In some embodiments, the second solvent includes an aromatic hydrocarbon solvent.

[0133] Specifically, the aromatic hydrocarbon solvent is one or more of toluene and xylene, and specifically, the aromatic hydrocarbon solvent is xylene.

[0134] In some embodiments, based on the total mass of the raw materials for preparing the modified copolymerized acrylic resin, the mass proportion of the alicyclic diamine is 2% to 7.5%, the mass proportion of the cyclic anhydride is 5.3% to 14.5%, the mass proportion of the functional additive is 0.01% to 0.1%, and the mass proportion of the third solvent is 2% to 7%.

[0135] In some embodiments, based on the total mass of the raw materials for preparing the modified copolymerized acrylic resin, the mass proportion of the alicyclic diamine is 2% to 7.1%, and the mass proportion of the cyclic anhydride is 5.3% to 13.5%.

[0136] In some embodiments, the alicyclic diamine has 4-6 ring atoms.

[0137] In some embodiments, the alicyclic diamine is a saturated alicyclic diamine.

[0138] Optionally, the alicyclic diamine includes at least one of 1,2-cyclobutanediamine, 1,3-cyclobutanediamine, 1,2-cyclopentanediamine, 1,3-cyclopentanediamine, 1,2-cyclohexanediamine, 1,3-cyclohexanediamine, 1,4-cyclohexanediamine and isophoronediamine.

[0139] Optionally, the alicyclic diamine includes at least one of 1,4-cyclohexanediamine and isophoronediamine (IPDA).

[0140] In some embodiments, the structure of the cyclic anhydride is as follows:

[0141]

[0142] Wherein, Ar includes any one of a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms and a substituted or unsubstituted aromatic group having 6 to 10 carbon atoms; each occurrence of R7 is independently selected from H or an alkyl group having 1 to 5 carbon atoms.

[0143] When the above groups are substituted, the substituents include alkyl groups having 1 to 5 carbon atoms.

[0144] In some embodiments, the cyclic anhydride includes at least one of phthalic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride.

[0145] In some embodiments, the cyclic anhydride includes hexahydrophthalic anhydride (HHPA) and methylhexahydrophthalic anhydride (MeHHPA).

[0146] In some embodiments, the functional aid includes an antioxidant, specifically 2,6-di-tert-butyl-4-methylphenol (BHT).

[0147] In some embodiments, the third solvent includes an aromatic hydrocarbon solvent.

[0148] Specifically, the aromatic hydrocarbon solvent is one or more of toluene and xylene, and specifically, the aromatic hydrocarbon solvent is xylene.

[0149] In this article, "at least one" or "one or several" can be one, two, three, four or more types of mixtures.

[0150] In some embodiments, the modified copolymerized acrylic resin has a solid content of 60 wt% to 80 wt%, a hydroxyl value of 185 mgKOH / g to 240 mgKOH / g, and a weight average molecular weight of 6,000 to 18,000.

[0151] One embodiment of the present invention further provides a method for preparing the modified copolymerized acrylic resin, comprising the following steps S10 to S90.

[0152] S10, mixing the cyclic acid anhydride, the auxiliary agent and part of the third solvent to prepare a first mixed solution.

[0153] S20, mixing the alicyclic diamine and the remaining portion of the third solvent to prepare a second mixed solution.

[0154] S30, dropping the second mixed solution into the first mixed solution to perform a ring-opening addition polymerization reaction to prepare polyamide.

[0155] It should be noted that there is no specific order for step S10 and step S20, and they can be performed one after the other or simultaneously.

[0156] In some embodiments, the temperature of the ring-opening addition polymerization is 50°C to 80°C.

[0157] In some embodiments, before step S30, the first mixed liquid is heated to 50°C to 80°C.

[0158] In some embodiments, during the preparation of polyamide, the ring-opening addition polymerization is stopped when the acid value of the reaction system is 230 mg KOH / g to 280 mg KOH / g.

[0159] In some embodiments, based on the total mass of the third solvent, the mass of the portion of the third solvent added in step S10 accounts for 50% to 90%.

[0160] S40, mixing polyamide, aliphatic diol, aliphatic polyol A, maleic anhydride and dibasic acid for polycondensation, and adding a second solvent for azeotropic dehydration to prepare a modified polymer.

[0161] In some embodiments, the temperature of the polycondensation reaction is 160±2°C to 230±2°C.

[0162] In some embodiments, during the preparation of the modified polymer, the polycondensation reaction is stopped when the acid value of the reaction system is 7 mgKOH / g to 9 mgKOH / g.

[0163] In a specific example, the polycondensation reaction process includes: heating the system to 160±2°C in 30 minutes, heating it to 230±2°C in 180 minutes and keeping it warm for 60 minutes, and then adding a second solvent for azeotropic dehydration until the acid value of the reaction system is 7mg KOH / g to 9mg KOH / g.

[0164] It is understandable that there is still some polycondensation reaction during the azeotropic dehydration process.

[0165] It should be noted that there is no specific order for steps S10 to S30 and step S40 , and they can be performed sequentially or simultaneously.

[0166] S50, mixing the modified polymer and the first portion of the first solvent to prepare a third mixed solution.

[0167] S60, mixing the comonomer, the hydroxyl functional monomer and the second portion of the first solvent to prepare a fourth mixed solution.

[0168] S70, mixing part of the initiator and the third part of the first solvent to prepare a fifth mixed solution.

[0169] S80, mixing the remaining portion of the initiator and the fourth portion of the first solvent to prepare a sixth mixed solution.

[0170] S90, dropping the fourth mixed liquid and the fifth mixed liquid into the third mixed liquid for polymerization reaction, then adding the sixth mixed liquid for aging treatment, and finally adding the remaining first solvent for dilution to prepare a modified copolymerized acrylic resin.

[0171] In some embodiments, in step S90 , the fourth mixed liquid and the fifth mixed liquid are simultaneously dripped into the third mixed liquid to perform a polymerization reaction.

[0172] In some embodiments, the polymerization reaction temperature is 130° C. to 150° C., and the polymerization time is 3.5 h to 6 h.

[0173] It should be noted that the polymerization reaction time includes the dropwise addition time, and is measured from the start of the dropwise addition.

[0174] Furthermore, in step S90, during the polymerization reaction, the dropwise addition time is 3 hours to 5 hours, and then the temperature is kept at 0.5 hours to 1 hour.

[0175] In some embodiments, before step S90, the third mixed liquid is heated to 130°C to 150°C.

[0176] In some embodiments, the aging treatment temperature is 130° C. to 150° C., and the time is 0.5 h to 1.5 h.

[0177] In some embodiments, the mass ratio of the first part of the first solvent, the second part of the first solvent, the third part of the first solvent, the fourth part of the first solvent and the remaining part of the first solvent is (2-24): (3-4): (2-3): (0.01-2): (1-4).

[0178] In some embodiments, based on the total mass of the initiator, the mass of the remaining initiator added in step S80 accounts for 1% to 15%.

[0179] In the above preparation method, alicyclic diamine and cyclic acid anhydride are first used as raw materials to prepare polyamide through a ring-opening addition polymerization reaction, and amide bonds are introduced to improve the wear resistance of the resin. Furthermore, polyamide is used as raw material and subjected to condensation polymerization with aliphatic diol, aliphatic polyol A, maleic anhydride, and dibasic acid. On the one hand, the aliphatic diol and aliphatic polyol A will esterify with the carboxylic acid on the polyamide, and on the other hand, the aliphatic diol, aliphatic polyol A, maleic anhydride, and dibasic acid are polarly condensed to introduce polyester segments for modification. In addition, one molecule of aliphatic polyol A contains three or more hydroxyl groups, which can increase the branching degree of the modified polymer and thus improve the numerical wear resistance. Further, the modified polymer, comonomer, and hydroxyl-functional monomer are polymerized under the action of an initiator to introduce propylene-based polymer segments into the modified polymer. At the same time, hydroxyl functional groups are introduced through the hydroxyl-functional monomer to provide crosslinking sites and improve the crosslinking degree of the resin after curing. In this way, the coordination of the components greatly improves the hardness of the resin after film formation, thereby improving the wear resistance.

[0180] Furthermore, one embodiment of the present invention provides a coating containing the above-mentioned modified copolymerized acrylic resin.

[0181] The coating comprises the modified copolymerized acrylic resin. The acrylic resin has high hardness and can improve the wear resistance of the coating film formed by the coating.

[0182] In some embodiments, the coating further comprises an additive.

[0183] It can be understood that the above-mentioned additives can be selected according to the actual application of the coating. For example, additives for improving the surface activity of the coating include dispersants, wetting agents, emulsifiers, demulsifiers, defoamers, foaming agents and antistatic agents; additives with catalytic effects include initiators, driers, curing agents, coupling agents, inhibitors, photoinitiators, anti-skinning agents, antioxidants, antibacterial agents, mildew inhibitors, etc.; functional additives include metal powders, graphite powders, carbon fibers, etc. required for conductive coatings, and titanium, aluminum, chromium, etc. used in radiation-proof coatings. Materials that can absorb and dissipate gamma rays, etc.

[0184] In some embodiments, the coating is a clear varnish coating.

[0185] One embodiment of the present invention further provides a coating product, which comprises a coating formed by the above-mentioned coating material.

[0186] The coating has high wear resistance, which can increase the service life of the coated products. Specific embodiments

[0188] Here, examples are given according to the technical solutions of the present invention, but the present invention is not limited to the following embodiments.

[0189] Example 1

[0190] (1) Preparation of polyamide:

[0191] Hexahydrophthalic anhydride HHPA (13.11%), antioxidant BHT (0.01%), and xylene (2.96%) are placed in a four-necked round-bottom flask and heated to 80°C. Then, 1,3-cyclobutanediamine (3.66%) is dropwise added to the four-necked round-bottom flask at a uniform rate over 15 minutes. The mixture is kept at 80°C for reaction. When the acid value is measured to be 280-290 mgKOH / g, heating is stopped and the mixture is cooled to obtain polyamide for standby use.

[0192] (2) Preparation of modified polymers:

[0193] The polyamide (19.74%) prepared above, 2,2-dimethyl-1,3-propanediol NPG (1.48%), 1,6-hexanediol 1,6-HD (3.35%), trimethylolpropane TMP (7.61%), adipic acid AD (6.21%), and maleic anhydride MAH (0.35%) were placed in a four-necked flask, heated to 160±2°C for 30 minutes, then uniformly heated to 230±2°C for 180 minutes, and then kept at 230±2°C for 60 minutes. The water separator was switched, and the reflux solvent toluene (2.54%) was added. The mixture was kept at 230±2°C until the acid value reached 7-9 mgKOH / g. The heating was stopped, and the total amount of reflux dehydration was approximately 4.63%. The modified polymer was cooled and set aside for use.

[0194] (3) Preparation of modified copolymerized acrylic resin:

[0195] The modified polymer (36.65%) prepared above, propylene glycol methyl ether acetate PMA (5.89%), and 100# aromatic hydrocarbon solvent (7.28%) were placed in a four-necked flask and heated to 150° C.; hydroxyethyl acrylate HEA (20.05%), isooctyl acrylate 2-EHA (5.97%), styrene St (11.34%), acrylic acid AAc (0.69%), 100# aromatic hydrocarbon solvent (2.00%), and propylene glycol methyl ether acetate PMA (2.00%) were placed in beaker I; di-tert-amyl hydroperoxide DTAP (1.04%), 100# aromatic hydrocarbon solvent (2.00%), and propylene glycol methyl ether acetate PMA (1.00%) were placed in beaker II; the systems in beaker II and beaker I were added dropwise to the four-necked flask system in parallel over 3 h. After the addition was complete, the reaction was kept at 150° C. for 30 min;

[0196] Di-tert-amyl hydroperoxide DTAP (0.1%), 100# aromatic hydrocarbon solvent (1.00%), and propylene glycol methyl ether acetate PMA (1.00%) were placed in beaker III and added to the four-necked flask system within 10 minutes. The mixture was kept at 150°C for 60 minutes, and then 100# aromatic hydrocarbon solvent (2.00%) was added to dilute the mixture to a solid content of 70±2%. The material was filtered through a 200-mesh filter cloth to obtain a modified copolymerized acrylic resin (solid content: 70%).

[0197] The ratio of each raw material (the percentage in the brackets above) is calculated based on the total mass of the raw materials for preparing the modified copolymerized acrylic resin, that is, the total mass of the modified polymer, comonomer, hydroxyl functional monomer, initiator and first solvent. Please see Table 1 for specific raw materials and their ratios.

[0198] (4) The acid value of the prepared modified copolymerized acrylic resin was tested in accordance with GB / T 2895-2008, and the weight-average molecular weight was tested using gel permeation chromatography. The test results are shown in Table 1.

[0199] Example 2

[0200] (1) Preparation of polyamide:

[0201] Methylhexahydrophthalic anhydride MeHHPA (10.94%), antioxidant BHT (0.01%), and xylene (2.59%) are placed in a four-necked round-bottom flask and heated to 80°C. 1,4-cyclohexanediamine (3.71%) is added dropwise to the four-necked round-bottom flask at a uniform rate over 15 minutes. The flask is kept at 80°C for reaction. When the acid value is measured to be 280-290 mgKOH / g, heating is stopped and the flask is cooled to obtain polyamide for standby use.

[0202] (2) Preparation of modified polymers:

[0203] The polyamide (17.25%) prepared above, 3-methyl-1,5-pentanediol MPD (1.28%), 1,6-hexanediol 1,6-HD (2.56%), pentaerythritol PETS (5.9%), 1,4-cyclohexanedicarboxylic acid CHDA (5.6%), and maleic anhydride MAH (0.27%) were placed in a four-necked flask and heated to 160±2°C for 30 minutes, then uniformly heated to 230±2°C for 180 minutes, and then kept at 230±2°C for 60 minutes. The water separator was switched, and the reflux solvent xylene (2.13%) was added. The mixture was kept at 230±2°C until the acid value reached 7-9 mgKOH / g. The heating was stopped, at which point the total amount of reflux dehydration was approximately 3.53%. The modified polymer was cooled and ready for use.

[0204] (3) Preparation of modified copolymerized acrylic resin:

[0205] The modified polymer (31.46%) prepared above, propylene glycol methyl ether acetate (PMA) (5.9%), and 100# aromatic hydrocarbon solvent (17.99%) were placed in a four-necked flask and heated to 150°C; hydroxypropyl acrylate (HPA) (19.29%), dodecyl acrylate (SLA) (4.11%), styrene St (8.67%), methacrylate (MAAc) (0.59%), 100# aromatic hydrocarbon solvent (2.00%), and propylene glycol methyl ether acetate (PMA) (2.00%) were placed in beaker I; Perbutylo (0.88%), 100# aromatic hydrocarbon solvent (2.00%), and propylene glycol methyl ether acetate (PMA) (1.00%) were placed in beaker II; the systems in beakers II and I were added dropwise to the system in the four-necked flask over a period of 3 hours. After the addition was complete, the mixture was kept at 150°C for 30 minutes.

[0206] Perbutylo (0.1%), 100# aromatic hydrocarbon solvent (1.00%), and propylene glycol methyl ether acetate (PMA) (1.00%) were placed in beaker III and added to the four-necked flask system within 10 minutes. The mixture was kept at 150°C for 60 minutes, and 100# aromatic hydrocarbon solvent (2.00%) was added to dilute the mixture to a solid content of 60±2%. The mixture was filtered through a 200-mesh filter cloth to obtain a modified copolymerized acrylic resin (solid content: 60%).

[0207] Step (4) is the same as step (4) in Example 1.

[0208] Example 3

[0209] (1) Preparation of polyamide:

[0210] Hexahydrophthalic anhydride HHPA (12.8%), antioxidant BHT (0.01%), and xylene (3.51%) are placed in a four-necked round-bottom flask and heated to 80°C. Isophorone diamine IPDA (7.07%) is added dropwise to the flask at a uniform rate over 15 minutes and kept at 80°C for reaction. When the acid value is measured to be 280-290 mgKOH / g, heating is stopped and the mixture is cooled to obtain a polyamide for use.

[0211] (2) Preparation of modified polymers:

[0212] The polyamide (23.39%) prepared above, 2-ethyl-2-butyl-1,3-propanediol BEPG (2.22%), 1,6-hexanediol 1,6-HD (3.27%), trimethylolpropane TMP (7.43%), isophthalic acid IPA (6.9%), and maleic anhydride MAH (0.34%) were placed in a four-necked flask, heated to 160±2°C for 30 minutes, uniformly heated to 230±2°C for 180 minutes, and then kept at 230±2°C for 60 minutes. The water separator was switched, and the reflux solvent xylene (2.76%) was added. The mixture was kept at 230±2°C until the acid value reached 7-9 mgKOH / g. The heating was stopped, and the total amount of reflux dehydration was approximately 4.51%. The modified polymer was cooled and set aside for use.

[0213] (3) Preparation of modified copolymerized acrylic resin:

[0214] The modified polymer (41.8%) prepared above and propylene glycol methyl ether acetate PMA (2.47%) were placed in a four-necked flask and heated to 150° C.; hydroxyethyl methacrylate HEMA (25.64%), isooctyl methacrylate 2-EHMA (5.92%), styrene St (11.07%), acrylic acid AAc (0.79%), 100# aromatic hydrocarbon solvent (2.00%), and propylene glycol methyl ether acetate PMA (2.00%) were placed in beaker I; di-tert-butyl hydroperoxide DTBP (1.2%), 100# aromatic hydrocarbon solvent (1.60%), and propylene glycol methyl ether acetate PMA (1.40%) were placed in beaker II; the systems in beakers II and beaker I were added dropwise to the four-necked flask system in parallel over 3 h. After the addition was complete, the reaction was kept at 150° C. for 30 min;

[0215] Di-tert-butyl hydroperoxide DTBP (0.1%) and propylene glycol methyl ether acetate PMA (2.00%) were placed in beaker III and added to the four-necked flask system within 10 minutes. The mixture was kept at 150° C. for 60 minutes, and then propylene glycol methyl ether acetate PMA (2.00%) was added to dilute the mixture to a solid content of 80±2%. The mixture was filtered through a 200-mesh filter cloth to obtain a modified copolymerized acrylic resin (solid content: 80%).

[0216] Step (4) is the same as step (4) in Example 1.

[0217] Example 4

[0218] (1) Preparation of polyamide:

[0219] Hexahydrophthalic anhydride HHPA (14.01%), antioxidant BHT (0.01%), and xylene (3.16%) are placed in a four-necked round-bottom flask and heated to 80°C. 1,3-cyclobutanediamine (3.91%) is added dropwise to the four-necked round-bottom flask at a uniform rate over 15 minutes. The mixture is kept at 80°C for reaction. When the acid value is measured to be 280-290 mgKOH / g, heating is stopped and the mixture is cooled to obtain polyamide for standby use.

[0220] (2) Preparation of modified polymers:

[0221] The polyamide (21.09%) prepared above, 2,2-dimethyl-1,3-propanediol NPG (1.58%), 1,6-hexanediol 1,6-HD (3.58%), trimethylolpropane TMP (8.13%), adipic acid AD (6.64%), and maleic anhydride MAH (0.37%) were placed in a four-necked flask, heated to 160±2°C for 30 minutes, then uniformly heated to 230±2°C for 180 minutes, and then kept at 230±2°C for 60 minutes. The water separator was switched, and the reflux solvent toluene (2.71%) was added. The mixture was kept at 230±2°C until the acid value reached 7-9 mgKOH / g. The heating was stopped, and the total amount of reflux dehydration was approximately 4.94%. The modified polymer was cooled and set aside for use.

[0222] (3) Preparation of modified copolymerized acrylic resin:

[0223] The modified polymer (39.16%) prepared above, propylene glycol methyl ether acetate PMA (5.86%), and 100# aromatic hydrocarbon solvent (1.92%) were placed in a four-necked flask and heated to 150°C; hydroxyethyl methacrylate HEMA (26.59%), dodecyl acrylate SLA (10.6%), isooctyl methacrylate 2-EHMA (2.72%), acrylic acid AAc (0.74%), 100# Aromatic hydrocarbon solvent (2.00%) and propylene glycol monomethyl ether acetate (PMA) (2.00%) were placed in beaker I; di-tert-amyl hydroperoxide (DTAP) (1.32%), 100# aromatic hydrocarbon solvent (2.00%), and propylene glycol monomethyl ether acetate (PMA) (1.00%) were placed in beaker II; the systems in beakers II and I were added dropwise to the four-necked flask system over a period of 3 h. After the addition was complete, the reaction was kept at 150°C for 30 min.

[0224] Di-tert-amyl hydroperoxide DTAP (0.10%), 100# aromatic hydrocarbon solvent (1.00%), and propylene glycol methyl ether acetate PMA (1.00%) were placed in beaker III and added to the four-necked flask system within 10 minutes. The mixture was kept at 150°C for 60 minutes, and 100# aromatic hydrocarbon solvent (2.00%) was added to dilute the mixture to a solid content of 75±2%. The mixture was filtered through a 200-mesh filter cloth to obtain a modified copolymerized acrylic resin (solid content: 75%).

[0225] Step (4) is the same as step (4) in Example 1.

[0226] Example 5

[0227] (1) Preparation of polyamide:

[0228] Hexahydrophthalic anhydride HHPA (5.7%), methylhexahydrophthalic anhydride MeHHPA (6.22%), antioxidant BHT (0.01%), and xylene (3.04%) are placed in a four-necked round-bottom flask and heated to 80°C. 1,4-cyclohexanediamine (2.11%) and isophoronediamine IPDA (3.15%) are uniformly added dropwise to the four-necked round-bottom flask over 15 minutes. The mixture is kept at 80°C for reaction. When the acid value is measured to be 280-290 mgKOH / g, heating is stopped and the mixture is cooled to obtain a polyamide for standby use.

[0229] (2) Preparation of modified polymers:

[0230] The polyamide (20.23%) prepared above, 2-ethyl-2-butyl-1,3-propanediol BEPG (1.98%), 1,6-hexanediol 1,6-HD (2.92%), trimethylolpropane TMP (6.62%), isophthalic acid IPA (6.15%), and maleic anhydride MAH (0.3%) were placed in a four-necked flask, heated to 160±2°C for 30 minutes, uniformly heated to 230±2°C for 180 minutes, and then kept at 230±2°C for 60 minutes. The water separator was switched, and the reflux solvent xylene (2.46%) was added. The mixture was kept at 230±2°C until the acid value reached 7-9 mgKOH / g. The heating was stopped, and the total amount of reflux dehydration was approximately 4.02%. The modified polymer was cooled and set aside for use.

[0231] (3) Preparation of modified copolymerized acrylic resin:

[0232] The modified polymer (36.64%) prepared above, propylene glycol methyl ether acetate PMA (5.89%), and 100# aromatic hydrocarbon solvent (7.28%) were placed in a four-necked flask and heated to 150°C; hydroxyethyl methacrylate HEMA (10.47%), hydroxypropyl methacrylate HPMA (11.6%), isooctyl acrylate 2-EHA (5.42%), styrene St (4.93%), dodecyl methacrylate SLMA (4.93%), Acrylic acid (AAc) (0.69%), 100# aromatic hydrocarbon solvent (2.00%), and propylene glycol methyl ether acetate (PMA) (2.00%) were placed in beaker I. Perbutylo (1.04%), 100# aromatic hydrocarbon solvent (2.00%), and propylene glycol methyl ether acetate (PMA) (1.00%) were placed in beaker II. The systems in beakers II and I were added dropwise to the four-necked flask over a period of 3 h. After the addition was complete, the mixture was kept at 150°C for 30 min.

[0233] Perbutylo (0.1%), 100# aromatic hydrocarbon solvent (1.00%), and propylene glycol methyl ether acetate (PMA) (1.00%) were placed in beaker III and added to the four-necked flask system within 10 minutes. The mixture was kept at 150°C for 60 minutes, and 100# aromatic hydrocarbon solvent (2.00%) was added to dilute the mixture to a solid content of 70±2%. The mixture was filtered through a 200-mesh filter cloth to obtain a modified copolymerized acrylic resin (solid content: 70%).

[0234] Step (4) is the same as step (4) in Example 1.

[0235] Example 6

[0236] (1) Preparation of polyamide:

[0237] Hexahydrophthalic anhydride HHPA (5.81%), methylhexahydrophthalic anhydride MeHHPA (6.34%), antioxidant BHT (0.01%), and xylene (3.09%) are placed in a four-necked round-bottom flask and heated to 80°C. 1,4-cyclohexanediamine (2.15%) and isophoronediamine IPDA (3.21%) are uniformly added dropwise to the four-necked round-bottom flask over 15 minutes, and the mixture is kept at 80°C for reaction. When the acid value is measured to be 280-290 mgKOH / g, heating is stopped and the mixture is cooled to obtain polyamide for use.

[0238] (2) Preparation of modified polymers:

[0239] The polyamide (20.61%) prepared above, 2-ethyl-2-butyl-1,3-propanediol BEPG (2.01%), 1,6-hexanediol 1,6-HD (2.97%), trimethylolpropane TMP (6.74%), adipic acid AD (2.56%), isophthalic acid IPA (3.13%), and maleic anhydride MAH (0.31%) were placed in a four-necked flask and heated to 160±2°C for 30 minutes, then uniformly heated to 230±2°C for 180 minutes, and then kept at 230±2°C for 60 minutes. The water separator was switched, and the reflux solvent xylene (2.41%) was added. The mixture was kept at 230±2°C until the acid value reached 7-9 mgKOH / g. The heating was stopped, and the total amount of reflux dehydration was approximately 4.09%. The modified polymer was cooled and set aside for use.

[0240] (3) Preparation of modified copolymerized acrylic resin:

[0241] The modified polymer (36.65%) prepared above, propylene glycol methyl ether acetate PMA (5.89%), and 100# aromatic hydrocarbon solvent (7.28%) were placed in a four-necked flask and heated to 150°C; hydroxyethyl methacrylate HEMA (10.66%), hydroxypropyl methacrylate HPMA (11.81%), isooctyl acrylate 2-EHA (4.84%), styrene St (5.02%), dodecyl methacrylate SLMA (5.02%), acrylic acid AA c (0.69%), 100# aromatic hydrocarbon solvent (2.00%), and propylene glycol methyl ether acetate PMA (2.00%) are placed in beaker I; di-tert-butyl hydroperoxide DTBP (0.54%), di-tert-amyl hydroperoxide DTAP (0.5%), 100# aromatic hydrocarbon solvent (2.00%), and propylene glycol methyl ether acetate PMA (1.00%) are placed in beaker II, and the monomers and initiators are added dropwise at a constant speed for 3 hours. After the addition is complete, the mixture is kept at 150°C for 30 minutes;

[0242] Di-tert-butyl hydroperoxide DTBP (0.1%), 100# aromatic hydrocarbon solvent (1.00%), and propylene glycol methyl ether acetate PMA (1.00%) were placed in beaker III and added to the four-necked flask system within 10 minutes. The mixture was kept at 150°C for 60 minutes, and 100# aromatic hydrocarbon solvent (2.00%) was added to dilute the mixture to a solid content of 70±2%. The material was filtered through a 200-mesh filter cloth to obtain a modified copolymerized acrylic resin (solid content: 70%).

[0243] Step (4) is the same as step (4) in Example 1.

[0244] Comparative Examples 1-2

[0245] Comparative Examples 1 and 2 are substantially the same as Example 1, with the only difference being the parameters in Table 1, for details see Table 1. Other steps and conditions are the same as in Example 1.

[0246] Comparative Example 3

[0247] (1) Preparation of modified polymers:

[0248] Hexahydrophthalic anhydride HHPA (11.9%), 2-ethyl-2-butyl-1,3-propanediol BEPG (5.13%), 1,6-hexanediol 1,6-HD (5.3%), trimethylolpropane TMP (6.88%), adipic acid AD (2.62%), isophthalic acid IPA (3.19%), and maleic anhydride MAH (0.31%) were placed in a four-necked flask, heated to 160±2°C for 30 minutes, then uniformly heated to 230±2°C over 180 minutes, and then kept at 230±2°C for 60 minutes. The water separator was switched, and reflux solvent xylene (5.5%) was added. The mixture was kept at 230±2°C until the acid value reached 7-9 mgKOH / g. The heating was stopped, and the total amount of reflux dehydration was approximately 4.18%. The polyester prepolymer was cooled and set aside for use.

[0249] (2) Preparation of modified copolymerized acrylic resin:

[0250] The modified polymer (36.65%) prepared above, propylene glycol methyl ether acetate PMA (5.88%), and 100# aromatic hydrocarbon solvent (7.28%) were placed in a four-necked flask and heated to 150°C; hydroxyethyl methacrylate HEMA (10.89%), hydroxypropyl methacrylate HPMA (12.06%), isooctyl acrylate 2-EHA (4.15%), styrene St (5.13%), dodecyl methacrylate SLMA (5. 13%), acrylic acid AAc (0.69%), 100# aromatic hydrocarbon solvent (2.00%), and propylene glycol methyl ether acetate PMA (2.00%) are placed in beaker I; di-tert-amyl hydroperoxide DTAP (1.04%), 100# aromatic hydrocarbon solvent (2.00%), and propylene glycol methyl ether acetate PMA (1.00%) are placed in beaker II, and the monomers and initiators are added dropwise at a constant speed for 3 hours, and the monomers and initiators are added dropwise into the system at the same time. After the addition is completed, the mixture is kept warm at 150°C for 30 minutes;

[0251] Di-tert-amyl hydroperoxide DTAP (0.1%), 100# aromatic hydrocarbon solvent (1.00%), and propylene glycol methyl ether acetate PMA (1.00%) were placed in beaker III and added to the four-necked flask system within 10 minutes. The mixture was kept at 150°C for 60 minutes, and 100# aromatic hydrocarbon solvent (2.00%) was added to dilute the mixture to a solid content of 70±2%. The material was filtered through a 200-mesh filter cloth to obtain a modified copolymerized acrylic resin (solid content: 70%).

[0252] The compositions of Examples 1 to 6 and Comparative Examples 1 to 3 are shown in Table 1.

[0253] Table 1

[0254]

[0255]

[0256] Example 7: Preparation of varnish

[0257] Coatings were prepared according to the formula shown in Table 2. The modified copolymerized acrylic resins prepared in Examples 1-6 and Comparative Examples 1-2 were formulated into corresponding clear varnishes A1-A6 and B1-2. The modified copolymerized acrylic resin in Comparative Example 3 was formulated into comparative coating B3. Mitsubishi Rayon modified acrylic resin CZ-2620 was formulated into comparative coating B4. The coating performance parameters were evaluated. The NCO:OH ratio in the coatings was fixed at 1.1:1. The specific steps are as follows:

[0258] The coating was made into a coating and tested using an SDL ATLAS M238BB Model CM-5 Crockmeter according to the following experimental method:

[0259] 1. Experimental equipment and model: SDL ATLAS M238BB Model CM-5 Crockmeter;

[0260] 2. Sandpaper for the experiment: 2400 grit, 30mm diameter, SiC adhesive-backed sandpaper;

[0261] 3. Experimental steps and result evaluation:

[0262] 3.1 Mark the scratch test position and three gloss measurement positions on the test plate. The gloss measurement position divides the scratch test position into four equal parts.

[0263] 3.2 Use a gloss meter to measure the gloss at the location marked for gloss measurement and record the 20° gloss (initial G20);

[0264] 3.3 Set the number of wipes to 15 times;

[0265] 3.4 Stick the sandpaper on the instrument. Do not allow the sandpaper to be pasted crookedly, wrinkled or otherwise abnormal.

[0266] 3.5 Place the sample on the operating table with the test surface facing up and hold the sample with both hands. Do not allow the sample to shake or move during the test.

[0267] 4.6 Start the test. After the test, use a gloss meter to measure the gloss at the location marked for gloss measurement and record the 20° gloss (G20 after scratching).

[0268] 3.7 A set of experiments is conducted three times in total and the average value is obtained. If one of the three results deviates from the average value by more than 10%, the result must be discarded and the test must be repeated. If two results deviate from the average value by 10%, the board must be retested.

[0269] 4. Other requirements:

[0270] 4.1 Before testing, place the sample at a temperature of (23 ± 2) °C and a relative humidity of (50 ± 5)% for at least 24 hours.

[0271] 4.2 The experimental conditions were temperature (23±2)℃ and relative humidity (50±5)%.

[0272] 4.3 Pay attention to observe whether there are any abnormal phenomena during the experiment and record them.

[0273] 4.4 The surface of the test sample is not allowed to have defects such as particles and scratches that may affect the measurement results.

[0274] Please see Table 2 for the specific components and Table 3 for the test results.

[0275] Table 2

[0276]

[0277]

[0278] Table 3

[0279] Initial G20 (mean) G20 after scratch (average) Light loss rate A1 88.1 81.9 7.04％ A 2 89.4 78.1 12.64％ A 3 88.7 79.5 10.37％ A 4 89.5 83.5 6.70％ A 5 88.2 80.5 8.73％ A 6 88.6 80.1 9.59％ B1 84.2 62.5 25.77％ B2 85.3 57.2 32.94％ B3 87.5 55.3 36.80％ B4 87.8 72.5 17.43％

[0280] Wherein, gloss loss rate = (initial G20 - G20 after scratching) / initial G20 × 100%

[0281] Analysis of the data in Table 1 shows that, compared with the coatings prepared from Comparative Examples 1 to 2, Comparative Example 3 without amide-modified fat, and Mitsubishi Rayon modified acrylic resin CZ-2620, the resins prepared from Examples 1 to 6 of the technical solution of the present application can significantly improve the abrasion resistance of the coating film.

[0282] At the same time, the coating appearance, acid resistance, alkali resistance, weather resistance and other indicators were also tested, and all met the performance requirements.

[0283] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0284] The above embodiments merely illustrate several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A modified copolymer acrylic resin, characterized in that: The raw materials for preparing the modified copolymerized acrylic resin include, by mass percentage, 31% to 42% of a modified polymer, 13% to 18.5% of a comonomer, 19% to 27% of a hydroxyl functional monomer, 0.5% to 1.5% of an initiator, and 14% to 39% of a first solvent; the comonomer includes an acrylic monomer; The modified copolymer acrylic resin is prepared by using the total mass of the raw materials as a benchmark, and the raw materials for preparing the modified polymer include, by mass percentage, 17% to 22% of polyamide, 1% to 6% of aliphatic diol, 5.5% to 9.5% of aliphatic polyol A, 0.2% to 0.5% of maleic anhydride, 5.5% to 12% of dibasic acid, and 2% to 3% of a second solvent; one molecule of the aliphatic polyol A contains three or more hydroxyl groups; Based on the total mass of the raw materials for preparing the modified copolymer acrylic resin, the raw materials for preparing the polyamide include, by mass percentage, 2% to 7.5% of alicyclic diamine, 5.3% to 14.5% of cyclic acid anhydride, 0.01% to 0.1% of a functional additive and 2% to 7% of a third solvent, wherein the cyclic acid anhydride contains at least one structure of a cycloalkyl group and an aromatic group.

2. The modified copolymer acrylic resin according to claim 1, wherein The modified copolymerized acrylic resin is a multi-branched polymer.

3. The modified copolymer acrylic resin according to any one of claims 1 to 2, characterized in that The comonomer includes a first comonomer and a second comonomer, wherein the first comonomer is as shown in formula (1): R1 is selected from alkanes having 1 to 15 carbon atoms; The second comonomer includes at least one of a compound represented by formula (2) and a vinyl monomer containing an aromatic group: Here, R3 is selected from any one of a chain alkyl group having 1 to 15 carbon atoms and a cycloalkyl group having 3 to 15 carbon atoms, and R2 is selected from a chain alkyl group having 1 to 5 carbon atoms.

4. The modified copolymer acrylic resin according to any one of claims 1 to 2, characterized in that The comonomer includes a first comonomer and a second comonomer, and the first comonomer includes at least one of acrylic acid and methacrylic acid.

5. The modified copolymer acrylic resin according to claim 4, wherein The second comonomer includes at least one of methyl acrylate, n-butyl acrylate, isobutyl acrylate, isobornyl acrylate, isooctyl acrylate, dodecyl acrylate, methyl methacrylate, n-butyl methacrylate, isobornyl methacrylate, isooctyl methacrylate, dodecyl methacrylate and an aromatic group-containing vinyl monomer.

6. The modified copolymer acrylic resin according to claim 5, wherein The aromatic group-containing vinyl monomer includes styrene.

7. The modified copolymer acrylic resin according to any one of claims 5 to 6, characterized in that Based on the total mass of the raw materials for preparing the modified copolymerized acrylic resin, the mass proportion of the first comonomer is 0.5% to 1%, and the mass proportion of the second comonomer is 12.5% ​​to 17.5%.

8. The modified copolymer acrylic resin according to any one of claims 1 to 2, characterized in that The modified polymer satisfies at least one of the following conditions (4) to (5): (4) Based on the total mass of the raw materials for preparing the modified copolymerized acrylic resin, the mass proportion of the aliphatic diol is 2% to 6%, the mass proportion of the aliphatic polyol A is 5.5% to 7.5%, the mass proportion of the dibasic acid is 5.5% to 8%, and the mass proportion of the maleic anhydride is 0.2% to 0.4%; (5) The modified polymer is a branched copolymer.

9. The modified copolymer acrylic resin according to any one of claims 1 to 2, characterized in that Based on the total mass of the raw materials for preparing the modified copolymerized acrylic resin, the mass proportion of the alicyclic diamine is 2% to 7.1%, and the mass proportion of the cyclic anhydride is 5.3% to 13.5%.

10. The modified copolymer acrylic resin according to any one of claims 1 to 2, characterized in that: The hydroxyl functional monomer is shown in formula (3): Among them, R4 is selected from a chain alkyl group having 1 to 5 carbon atoms, and R5 is selected from a chain alkyl group having 1 to 5 carbon atoms.

11. The modified copolymer acrylic resin according to any one of claims 1 to 2, characterized in that: The hydroxyl functional monomer includes at least one of hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, hydroxybutyl acrylate and hydroxybutyl methacrylate.

12. The modified copolymer acrylic resin according to any one of claims 1 to 2, characterized in that: The initiator includes a peroxide compound initiator; The first solvent includes at least one of an aromatic hydrocarbon solvent and an alcohol ether solvent.

13. The modified copolymerized acrylic resin according to any one of claims 1 to 2, 5 to 6, characterized in that: The raw materials for preparing the modified polymer meet at least one of the following conditions (6) to (8): (6) The aliphatic diol includes at least one of 2,2-dimethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, and 2-ethyl-2-butyl-1,3-propanediol; (7) the aliphatic polyol A comprises at least one of trimethylolpropane and pentaerythritol; (8) The dibasic acid includes at least one of an aromatic dibasic acid and an aliphatic dibasic acid.

14. The modified copolymerized acrylic resin according to claim 13, wherein The raw materials for preparing the modified polymer meet at least one of the following conditions (9) to (10): (9) The aliphatic diol includes at least one of 2,2-dimethyl-1,3-propanediol and 1,6-hexanediol; (10) The dibasic acid includes at least one of isophthalic acid, adipic acid, and 1,4-cyclohexanedicarboxylic acid.

15. The modified copolymerized acrylic resin according to any one of claims 1 to 2, 5 to 6, characterized in that: The raw materials for preparing the polyamide satisfy at least one of the following conditions (11) to (13): (11) The number of ring atoms of the alicyclic diamine is 4 to 6; (12) The cyclic acid anhydride includes at least one of phthalic anhydride, hexahydrophthalic anhydride and methylhexahydrophthalic anhydride; (13) The functional auxiliary agent includes an antioxidant.

16. The modified copolymerized acrylic resin according to claim 15, wherein The alicyclic diamine includes at least one of 1,2-cyclobutanediamine, 1,3-cyclobutanediamine, 1,2-cyclopentanediamine, 1,3-cyclopentanediamine, 1,2-cyclohexanediamine, 1,3-cyclohexanediamine, 1,4-cyclohexanediamine and isophoronediamine.

17. The modified copolymerized acrylic resin according to any one of claims 1 to 2, 5 to 6 and 16, characterized in that: The modified copolymerized acrylic resin has a solid content of 60 wt% to 80 wt%, a hydroxyl value of 185 mgKOH / g to 240 mgKOH / g, and a weight-average molecular weight of 6,000 to 18,000.

18. A method for preparing the modified copolymerized acrylic resin according to any one of claims 1 to 17, characterized in that: The following steps are involved: Mixing the cyclic anhydride, the auxiliary agent, and a portion of the third solvent to prepare a first mixed solution; mixing the alicyclic diamine and the remaining portion of the third solvent to prepare a second mixed solution; dropping the second mixed solution into the first mixed solution to carry out a ring-opening addition polymerization reaction to prepare the polyamide; The polyamide, the aliphatic diol, the aliphatic polyol A, the maleic anhydride and the dibasic acid are mixed for polycondensation, and the second solvent is added for azeotropic dehydration to prepare the modified polymer; mixing the modified polymer and the first portion of the first solvent to prepare a third mixed solution; mixing the comonomer, the hydroxyl functional monomer, and a second portion of the first solvent to prepare a fourth mixed solution; mixing a portion of the initiator and a third portion of the first solvent to prepare a fifth mixed solution; mixing the remaining portion of the initiator and the fourth portion of the first solvent to prepare a sixth mixed solution; The fourth mixed liquid and the fifth mixed liquid are dropped into the third mixed liquid to carry out polymerization reaction, and then the sixth mixed liquid is added for aging treatment, and finally the remaining first solvent is added for dilution to prepare the modified copolymer acrylic resin.

19. The method for preparing the modified copolymerized acrylic resin according to claim 18, wherein: The ring-opening addition polymerization reaction satisfies at least one of the following conditions (14) to (15); (14) The temperature of the ring-opening addition polymerization is 50° C. to 80° C.; (15) During the preparation of the polyamide, when the acid value of the reaction system is 230 mg KOH / g to 280 mg KOH / g, stopping the ring-opening addition polymerization; The polycondensation reaction satisfies at least one of the following conditions (16) to (17); (16) The temperature of the polycondensation reaction is 160±2°C to 230±2°C; (17) During the preparation of the modified polymer, when the acid value of the reaction system is 7 mg KOH / g to 9 mg KOH / g, stopping the polycondensation reaction; The polymerization reaction satisfies at least one of the following conditions (18) to (19); (18) The polymerization reaction temperature is 130° C. to 150° C. and the reaction time is 3.5 h to 6 h; (19) The temperature of the aging treatment is 130°C to 150°C, and the time is 0.5h to 1.5h.

20. A coating, characterized in that: The coating contains the modified copolymer acrylic resin described in any one of items 1 to 17.

21. A coating product, characterized in that: The coated product comprises a coating film formed from the coating material according to claim 20.

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