Composite spherical matting agent and preparation method thereof

Abstract

The application discloses a kind of composite spherical matting agent and preparation method thereof, and relates to the technical field of matting agent.The composite spherical matting agent includes, by weight parts: composite spherical resin 50-80 parts, polyamide anti-settling wax 2-5 parts, naphthenic white oil 5-10 parts, filler 1-5 parts, antioxidant 1-5 parts, solvent 30-50 parts, wherein the raw material of the composite spherical resin includes polyester resin and ethylene resin.The composite spherical matting agent of the application does not significantly affect the transparency of coating after application and has high weather resistance.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of matting agents, in particular to a composite spherical matting agent and a preparation method thereof. BACKGROUND

[0002] In the field of coatings and materials, matting agents are widely used, which mainly function to reduce the gloss of material surface to meet specific visual effects or functional requirements. However, traditional matting agents have some obvious deficiencies in practical application.

[0003] On the one hand, many matting agents have low transparency, which is mainly due to the uneven distribution of matting agent particles in the coating film or the large difference between the refractive index of the matting agent and the refractive index of the coating film matrix, resulting in scattering of light at the interface and thus significantly affecting the transparency of the coating film. For example, ordinary physical and chemical matting agents have poor compatibility in epoxy and polyester, which easily leads to white transparent powder and poor transparency. In practical application, a trade-off between transparency and matting property needs to be made, and appropriate components and proportions are selected through optimization of the formula and process to achieve the purpose of meeting the matting effect and maintaining the transparency of the coating as much as possible.

[0004] On the other hand, the weather resistance of some matting agents is poor, which is mainly because the organic components in the matting agent are easily affected by factors such as ultraviolet light and temperature changes when exposed to the natural environment for a long time, leading to degradation or discoloration and thus affecting the appearance and performance of the coating film. For example, some matting agents contain catalysts, curing agents, etc., which easily lead to yellowing of the coating film and affect the transparency when used outdoors.

[0005] Therefore, there is currently a lack of a matting agent that does not significantly affect the transparency of the coating after application and has high weather resistance. SUMMARY

[0006] The present application is made in view of the above problem, and provides a composite spherical matting agent and a preparation method thereof.

[0007] The present application provides a composite spherical matting agent, which comprises, by weight: 50-80 parts of a composite spherical resin, 2-5 parts of a polyamide anti-settling wax, 5-10 parts of naphthenic white oil, 1-5 parts of a filler, 1-5 parts of an antioxidant, and 30-50 parts of a solvent, wherein the raw material of the composite spherical resin comprises a polyester resin and an ethylene resin.

[0008] In some embodiments of the present application, the polyester resin comprises polyethylene terephthalate and / or polybutylene terephthalate, and the ethylene resin comprises divinylbenzene and / or ethylene glycol di(meth)acrylate.

[0009] In some embodiments of the present application, the weight ratio of the polyester resin and the ethylene resin is (3-5):1.

[0010] In some embodiments of the present application, the average particle size of the composite spherical resin is 10-50 μm; and / or, the viscosity of the composite spherical resin in a molten state is less than or equal to 0.7 dl / g at room temperature.

[0011] In some embodiments of the present application, the filler comprises nano calcium carbonate and modified molybdenum disulfide in a weight ratio of (1-4):1.

[0012] In some embodiments of the present application, the solvent comprises at least one of methyl isobutyl ketone, cyclohexanone, n-butyl acetate, ethyl acetate, butyl acetate, t-butyl alcohol, isobutyl alcohol, isopropyl alcohol, acetone, benzyl ether.

[0013] The second aspect of the present application provides a preparation method of a composite spherical matting agent, comprising the following steps:

[0014] S1, melting a polyester resin, adding an ethylene resin to continue heating and stirring, making the mixed particles spherical, and then spray drying to obtain a composite spherical resin;

[0015] S2, adding a solvent and the composite spherical resin in a stirring kettle, and then adding a filler, naphthenic white oil, and a polyamide anti-settling wax sheet in sequence, and high-speed dispersing to obtain a product to be post-processed;

[0016] S3, adding an antioxidant to the product to be post-processed, mixing, and aging to obtain a composite spherical matting agent.

[0017] In some embodiments of the present application, in step S1, the temperature of the melted polyester resin is 220-230°C; and / or, the temperature of the heating and stirring is 300-330°C.

[0018] In some embodiments of the present application, in step S1, the stirring rate of the heating and stirring is 800-1200 rpm, and the stirring time is 1.5-2 hours.

[0019] In some embodiments of the present application, in step S2, the atomization pressure of the spray drying is 0.8-1.2 MPa.

[0020] The present application can achieve the following beneficial effects:

[0021] The application provides a composite spherical extinction agent, the refractive index of the mixed resin is adjusted, the spherical structure helps uniform scattering of light, the low addition amount of the filler avoids introduction of too many light scattering points, and the composite spherical extinction agent can be added into paint to play a role in extinction without affecting the transparency of the paint, and the composite spherical extinction agent is applied to the paint without significantly affecting the transparency and has high weather resistance through regulation of the composite refractive index of the resin, optimization of the interface of the nano filler, and a synergistic system of anti-oxidation and anti-settling. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 FIG. 1 is a scanning electron microscope image of the composite spherical extinction agent of an embodiment of the application, with a magnification of 1000 times.

[0023] The implementation, functional characteristics and advantages of the application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0024] The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the application, and are not intended to limit the subject matter recited in the claims.

[0025] The "range" disclosed in the application is limited in the form of lower limit and upper limit, a given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of a particular range. The range defined in this way can include or not include the end value, and can be arbitrarily combined, i.e. any lower limit can be combined with any upper limit to form a range. For example, if the ranges of 60-120 and 80-110 are listed for a particular parameter, it is understood that the ranges of 60-110 and 80-120 are also anticipated. In addition, if the minimum range values 1 and 2 are listed, and if the maximum range values 3, 4 and 5 are listed, the following ranges are all anticipated: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In the application, unless otherwise specified, the numerical range "a-b" represents a shorthand representation of any real number combination between a and b, where a and b are both real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" have been listed herein, and "0-5" is only a shorthand representation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclose that the parameter is, for example, an integer 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0026] Unless otherwise specified, all embodiments and optional embodiments of the application can be combined with each other to form new technical solutions.

[0027] Unless otherwise specified, all technical features and optional technical features of the application can be combined with each other to form new technical solutions.

[0028] If not otherwise specified, all steps of the present application can be performed in any order, preferably in the order as specified. For example, the method comprises steps (a) and (b) means that the method can comprise steps (a) and (b) in the order as specified, or steps (b) and (a) in the order as specified. For example, the method can further comprise step (c) means that step (c) can be added to the method in any order, for example, the method can comprise steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.

[0029] In practical applications, in the field of coatings and materials, the application of matting agents is very wide, and its main function is to reduce the gloss of the surface of the material to meet the specific visual effect or functional requirement. It is necessary to balance between transparency and matting, and by optimizing the formula and process, selecting appropriate components and proportions, the purpose of meeting the matting effect and maintaining the transparency of the coating as much as possible is achieved. At present, there is a lack of a matting agent which is applied to the coating without significantly affecting its transparency and has high weather resistance.

[0030] In view of this, the present scheme provides a composite spherical matting agent, which comprises, by weight: 50-80 parts of composite spherical resin, 2-5 parts of polyamide anti-settling wax, 5-10 parts of naphthenic white oil, 1-5 parts of filler, 1-5 parts of antioxidant, and 30-50 parts of solvent, wherein the raw material of the composite spherical resin comprises polyester resin and ethylene resin.

[0031] In the composite spherical resin, the polyester resin has a higher refractive index, and after being compounded with the ethylene resin, the refractive index matching with the coating substrate can be achieved by adjusting the proportion of the two, the light scattering is reduced, and the coating transparency is improved. The coating substrate includes polycarbonate, polyacrylate, etc. The spherical particle surface is smooth, light is uniformly diffused and reflected on the particle surface, the interface scattering with the coating substrate is reduced, the gloss is reduced without affecting the overall coating transparency. The ethylene resin provides flexibility and hydrolysis resistance, and cooperates with the polyester to inhibit the cracking of the coating.

[0032] The polyamide anti-settling wax is adsorbed on the surface of the filler and resin particles by hydrogen bonding, prevents settling, ensures system uniformity, avoids local turbidity, and does not affect the system viscosity when the addition amount is ≤5 parts.

[0033] The naphthenic white oil has good compatibility with the polyester / ethylene resin, acts as a plasticizer to reduce the glass transition temperature, improve the low-temperature toughness of the matting agent, and reduce the volume shrinkage during the drying process of the coating. Moreover, the naphthenic structure has strong oxidation resistance, inhibits resin chain rupture, and avoids micro-cracks.

[0034] Antioxidants include hindered phenols and phosphites, such as Irganox 1010, Irgafos 168.

[0035] The composite spherical matting agent of the present solution adjusts the refractive index of the mixed resin matting agent, and the spherical structure helps to uniformly scatter light. The low addition amount of the filler avoids introducing too many light scattering points. When added to the coating, it can play a matting effect without affecting the transparency of the coating. Overall, by adjusting the composite refractive index through resin, optimizing the interface of nano fillers, and the synergistic system of anti-oxidation and anti-settling, the composite spherical matting agent is applied to the coating without significantly affecting its transparency and has high weather resistance.

[0036] In some embodiments, the polyester resin includes polyethylene terephthalate and / or polybutylene terephthalate, and the vinyl resin includes divinylbenzene and / or ethylene glycol di(meth)acrylate.

[0037] Polyethylene terephthalate (PET) and / or polybutylene terephthalate (PBT) have good mechanical properties and thermal stability, which helps to improve the weather resistance and adhesion of the matting agent. Divinylbenzene and / or ethylene glycol di(meth)acrylate can enhance the transparency and chemical resistance of the matting agent. The combination of the above resins not only provides good matting effect, but also ensures the stability of the matting agent in different environments and reduces the impact on transparency.

[0038] In some embodiments, the weight ratio of the polyester resin to the vinyl resin is (3-5):1. Preferably, the weight ratio is 3:1.

[0039] In some embodiments, the average particle size of the composite spherical resin is 10-50 μm; and / or, the viscosity of the composite spherical resin in the molten state at room temperature is less than or equal to 0.7 dl / g.

[0040] In some embodiments, the filler includes nano calcium carbonate and modified molybdenum disulfide in a weight ratio of (1-4):1. Preferably, the weight ratio is 2:1.

[0041] In some embodiments, the solvent includes at least one of methyl isobutyl ketone, cyclohexanone, n-butyl acetate, ethyl acetate, butyl acetate, tert-butyl alcohol, isobutyl alcohol, isopropyl alcohol, acetone, benzyl ether. Preferably, the solvent is methyl isobutyl ketone or n-butyl acetate, which can reduce the VOCs content and improve the environmental protection level of the matting agent without affecting the performance of the matting agent.

[0042] The second aspect of the present application provides a preparation method of a composite spherical matting agent, comprising the following steps:

[0043] S1, melting polyester resin, adding ethylene resin to continue heating and stirring, making mixed particles spheroidization, then spray drying to obtain composite spherical resin. In some embodiments, in step S1, the temperature of the melted polyester resin is 220-230°C; and / or, the temperature of the heating and stirring is 300-330°C. The stirring rate of the heating and stirring is 800-1200 rpm, and the stirring time is 1.5-2 hours.

[0044] S2, adding solvent and the composite spherical resin in a stirring tank, then adding filler, naphthenic white oil, and polyamide anti-settling wax sheet in sequence, high-speed dispersion to obtain a product to be post-processed. In some embodiments, the atomization pressure of the spray drying is 0.8-1.2 MPa.

[0045] S3, adding antioxidant to the product to be post-processed, mixing and aging to obtain a composite spherical matting agent. In some embodiments, in step S3, the aging is standing for greater than or equal to 24 hours.

[0046] The technical solutions of the present application are further described in detail below in combination with specific embodiments. It should be understood that the specific embodiments below are only used to explain the present application and do not limit the present application.

[0047] Example 1

[0048] 60 parts of raw material polyethylene terephthalate particles were put into a dispersion tank, heated to 230°C, and stirred at 1000 rpm until completely melted. Then 20 parts of ethylene glycol di(meth)acrylate particles were slowly added, the temperature was maintained at 325°C, and the stirring was continued for 1.5-2 hours. The viscosity was tested by IV3100R automatic viscometer and was 0.6 dl / g. The product was taken out and spray dried in a tower at an atomization pressure of 1.1 MPa. Under a scanning electron microscope, composite spherical resin with an average particle size of 10-50 μm was obtained.

[0049] In a planetary stirring tank, 40 parts of n-butyl acetate were added, and 65 parts of composite spherical resin microspheres were put in and stirred for 40 minutes. Then 2 parts of nano calcium carbonate, 1 part of modified molybdenum disulfide, and 6 parts of naphthenic white oil were added in sequence. After heating to 70°C, 3 parts of polyamide anti-settling wax sheet were added. After cooling to 50°C, I-1010 antioxidant was added. After standing for 24 hours, a composite spherical matting agent was obtained.

[0050] Example 2

[0051] With 50 parts of raw material polyethylene terephthalate particles by weight into the dispersion tank, heated to 230℃, stirring at 1000 rpm until completely melted, slowly add 10 parts of ethylene glycol di(methyl) acrylate particles, maintain temperature 325℃, stirring 1.5-2 hours, using IV3100R automatic viscometer, test viscosity is 0.6 dl / g, take the product in the tower spray drying, atomization pressure is 1.1 MPa, observed under scanning electron microscope, get the average particle size of 10-50 μm composite spherical resin;

[0052] In the planetary stirred tank, 40 parts of n-butyl acetate was added, 55 parts of composite spherical resin microspheres were put in, stirred for 40 minutes, 2 parts of nano calcium carbonate, 1 part of modified molybdenum disulfide, 6 parts of naphthenic white oil were added in turn, heated to 70℃, then 3 parts of polyamide anti-settling wax sheet was added, cooled to 50℃, then I-1010 antioxidant was added, and aged for 24 hours. Get composite spherical matting agent.

[0053] Example 3

[0054] With 60 parts of raw material polyethylene terephthalate particles by weight into the dispersion tank, heated to 230℃, stirring at 1000 rpm until completely melted, slowly add 20 parts of divinylbenzene particles, maintain temperature 325℃, stirring 1.5-2 hours, using IV3100R automatic viscometer, test viscosity is 0.6 dl / g, take the product in the tower spray drying, atomization pressure is 1.1 MPa, observed under scanning electron microscope, get the average particle size of 10-50 μm composite spherical resin;

[0055] In the planetary stirred tank, 40 parts of n-butyl acetate was added, 75 parts of composite spherical resin microspheres were put in, stirred for 40 minutes, 2 parts of nano calcium carbonate, 1 part of modified molybdenum disulfide, 6 parts of naphthenic white oil were added in turn, heated to 70℃, then 3 parts of polyamide anti-settling wax sheet was added, cooled to 50℃, then I-1010 antioxidant was added, and aged for 24 hours. Get composite spherical matting agent.

[0056] Example 4

[0057] With 60 parts of raw material polyethylene terephthalate particles by weight into the dispersion tank, heated to 230℃, stirring at 1000 rpm until completely melted, slowly add 20 parts of ethylene glycol di(methyl) acrylate particles, maintain temperature 325℃, stirring 1.5-2 hours, using IV3100R automatic viscometer, test viscosity is 0.6 dl / g, take the product in the tower spray drying, atomization pressure is 1.1 MPa, observed under scanning electron microscope, get the average particle size of 10-50 μm composite spherical resin;

[0058] In a planetary stirring kettle, 40 parts of n-butyl acetate were added, 65 parts of composite spherical resin microspheres were put in and stirred for 40 minutes, 1 part of nano calcium carbonate, 1 part of modified molybdenum disulfide and 6 parts of naphthenic white oil were added in turn, the temperature was raised to 70℃, then 3 parts of polyamide anti-settling wax sheet were added, the temperature was lowered to 50℃, then I-1010 antioxidant was added, and the mixture was aged for 24 hours to obtain the composite spherical matting agent.

[0059] Comparative Example 1

[0060] Without preparing composite resin microspheres, polyethylene terephthalate was used for melt spray drying to prepare single polyester resin microspheres, and other operations were the same as in Example 1.

[0061] Comparative Example 2

[0062] Without preparing composite resin microspheres, ethylene glycol di(meth)acrylate was used for melt spray drying to prepare single ethylene resin microspheres, and other operations were the same as in Example 1.

[0063] Performance test:

[0064] The composite spherical matting agents obtained in the examples and comparative examples were tested for performance, and the test contents included:

[0065] 1. Matting agent light transmittance: tested according to ASTM D1003 standard.

[0066] 2. Base material mixed light transmittance: 12% by weight of matting agent was added to a commercially available coating (Lusol GL038-3), and the light transmittance of the sample was tested according to ASTM D1003 standard.

[0067] 3. Haze: tested according to ASTM D1003 standard.

[0068] 4. QUV aging yellowing: tested according to ASTM G154 standard.

[0069] 5. Adhesion: tested according to ASTM D3359 standard.

[0070] 6. Cold and hot impact resistance: the test sample was kept at -30℃ for 10 minutes, then the temperature was raised to 80℃ for 10 minutes, and the temperature was lowered and raised for 10 times, the impact test was carried out according to ASTM D2794-2019, and the surface was observed after 5 times of impact.

[0071] The results are shown in Table 1:

[0072] Table 1: Test results of Examples 1-4 and Comparative Examples 1-2

[0073]

[0074]

[0075] It can be seen that the composite spherical matting agent provided by the scheme has the refractive index of the mixed resin matting agent, and the spherical structure helps uniform scattering of light, and the low addition amount of the filler avoids introducing too many light scattering points, and the addition to the paint can play a matting role without affecting the transparency of the paint, and the overall refractive index regulation through the resin composite, the interface optimization of the nano filler and the synergistic system of the anti-oxidation and anti-settling can realize that the composite spherical matting agent is applied to the paint without significantly affecting the transparency and has high weather resistance.

[0076] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and embodiments having the same technical idea and playing the same role and effect within the scope of the technical scheme of the present application are all included in the technical scope of the present application. In addition, within the scope of the main idea of the present application, various modifications that can be thought of by those skilled in the art are applied to the embodiments, and other ways constructed by combining part of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A composite spherical matting agent, characterized in that, The composite spherical matting agent comprises, by weight: 50-80 parts of composite spherical resin, 2-5 parts of polyamide anti-settling wax 5-10 parts of naphthenic white oil 1-5 parts of filler Antioxidant 1-5 parts, Solvent 30-50 parts, The raw materials for the composite spherical resin include polyester resin and ethylene resin; The polyester resin includes polyethylene terephthalate and / or polybutylene terephthalate, and the ethylene resin includes divinylbenzene particles or ethylene glycol di(meth)acrylate particles. The weight ratio of the polyester resin to the ethylene resin is (3~5):1; The average particle size of the composite spherical resin is 10μm~50μm.

2. The composite spherical matting agent according to claim 1, characterized in that, The filler comprises nano-calcium carbonate and modified molybdenum disulfide in a weight ratio of (1~4):

1.

3. The composite spherical matting agent according to claim 1, characterized in that, The solvent includes at least one of methyl isobutyl ketone, cyclohexanone, ethyl acetate, butyl acetate, tert-butanol, isobutanol, isopropanol, acetone, and anisole.

4. A method for preparing a composite spherical matting agent as described in any one of claims 1 to 3, characterized in that, Includes the following steps: S1. Melt polyester resin, add ethylene resin and continue heating and stirring to spheroidize the mixed particles, then spray dry to obtain composite spherical resin; S2. Add solvent and the composite spherical resin to a stirred tank, then add filler, naphthenic white oil and polyamide anti-settling wax in sequence, disperse at high speed to obtain the product to be post-processed; S3. Add antioxidants to the product to be post-treated, mix and mature to obtain a composite spherical matting agent.

5. The method for preparing the composite spherical matting agent according to claim 4, characterized in that, In step S1, the temperature for melting the polyester resin is 220℃~230℃; And / or, the temperature of the heating and stirring is 300℃~330℃.

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