A fabric ultraviolet absorber composition and a preparation method thereof

Abstract

This application relates to the technical field of polymer additives, and particularly to a fabric ultraviolet absorber composition and a preparation method thereof. A fabric ultraviolet absorber composition includes the following raw materials in parts by weight: 20-50 parts of an ultraviolet absorber, 6-13 parts of a dispersant, 0.3-0.8 parts of an antifoaming agent, and 80-180 parts of water; wherein the dispersant is an amino-terminated hyperbranched polymer grafted with nano-titanium dioxide. The UPF value of the ultraviolet absorber composition obtained in this application can reach 40+ or even 50+, the ultraviolet transmittance can reach 4.15-3.34%, and the change rate of D90 can reach 25.64-21.24% after the heat storage time at 80°C changes from 20 min to 40 min. The obtained ultraviolet absorber not only has excellent ultraviolet resistance but also stable heat storage particle size.

Description

Technical Field

[0001] This application relates to the technical field of polymer additives, and particularly to a fabric ultraviolet absorber composition and a preparation method thereof. Background Art

[0002] Ultraviolet rays exist all the time in our daily life. Appropriate ultraviolet radiation is beneficial to the human body, but excessive exposure to ultraviolet rays will damage the human body and affect health. As the first line of defense against ultraviolet radiation, textiles play an important role in preventing excessive ultraviolet radiation. It is particularly important to carry out anti-ultraviolet finishing on textiles with poor original anti-ultraviolet performance.

[0003] The anti-ultraviolet methods of fabrics mainly include two categories: the shielding method of improving the scattering and refraction of light by ultraviolet absorbers and the method of improving the absorption of ultraviolet rays.

[0004] Ultraviolet absorbers usually exist in the form of particles, and their particle size has an important impact on performance. Under thermal storage conditions, the particle size will change, which may affect the ultraviolet absorption efficiency, compatibility with other materials, etc. Therefore, it is quite necessary to design an ultraviolet absorber with stable particle size during thermal storage to improve the effect of ultraviolet rays. Summary of the Invention

[0005] In order to improve the thermal storage stability of ultraviolet absorbers, this application provides a fabric ultraviolet absorber composition and a preparation method thereof. In the first aspect, this application provides a fabric ultraviolet absorber composition, adopting the following technical solutions.

[0006] A fabric ultraviolet absorber composition, comprising the following raw materials in parts by weight: 20-50 parts of ultraviolet absorber, 6-13 parts of dispersant, 0.3-0.8 parts of defoamer, and 80-180 parts of water;

[0007] Wherein the dispersant is an amino-terminated hyperbranched polymer grafted with nano-titanium dioxide;

[0008] The preparation method of the amino-terminated hyperbranched polymer grafted with nano-titanium dioxide is as follows:

[0009] 1) Pretreat nano-titanium dioxide

[0010] Treat the surface of nano-titanium dioxide with sodium hydroxide solution to introduce hydroxyl groups on the surface of nano-titanium dioxide to obtain hydroxyl-nano-titanium dioxide;

[0011] 2) Introduce active groups

[0012] React γ-glycidoxypropyltrimethoxysilane with hydroxyl-nano-titanium dioxide to introduce epoxy groups on the surface of hydroxyl-nano-titanium dioxide to obtain epoxy-nano-titanium dioxide;

[0013] 3) Grafting reaction

[0014] Mix epoxy-nano titanium dioxide and amino-terminated hyperbranched polymer in a solvent, and react at 80 - 100 °C for 6 - 8 h under the action of a catalyst. After the reaction, centrifuge and dry to obtain amino-terminated hyperbranched polymer grafted with nano titanium dioxide.

[0015] The weight ratio of the nano titanium dioxide to the amino-terminated hyperbranched polymer is 1:(0.5 - 0.7).

[0016] By adopting the above technical solution, the hyperbranched polymer is compounded with nano titanium dioxide. The hyperbranched polymer has a highly branched structure and a large number of terminal functional groups, and can be combined with the ultraviolet absorber through physical adsorption or chemical bonding to provide good dispersion performance.

[0017] Using the amino-terminated hyperbranched polymer grafted with nano titanium dioxide as a dispersant, the dispersant molecules are adsorbed on the surface of the ultraviolet absorber particles to form an adsorption layer with a certain thickness, forming a three-dimensional steric hindrance to prevent the particles from aggregating due to collision during the heat storage process and maintaining their good dispersion state, thereby improving the thermal stability. At the same time, the dispersant makes the surface of the ultraviolet absorber particles generate static charges, causing the particles to repel each other. During the heat storage process, this electrostatic repulsive force can effectively prevent the particles from aggregating together due to thermal motion and maintain the uniform dispersion of the particles to ensure the stable performance of the ultraviolet absorber.

[0018] In addition, the amino-terminated hyperbranched polymer grafted with nano titanium dioxide can reduce the surface tension between the ultraviolet absorber and the surrounding medium, make the ultraviolet absorber better wetted by water, and play a bridging role between the ultraviolet absorber and water, promoting the intermolecular interaction between them and making the ultraviolet absorber better combined with the medium. During the heat storage process, it can avoid phase separation or precipitation caused by incompatibility with the medium, and can be more evenly dispersed in the medium when heated, reducing performance changes caused by too high or too low local concentration and improving the heat storage stability.

[0019] Furthermore, the preparation method of the amino-terminated hyperbranched polymer is as follows:

[0020] a) Dissolve 3,5-diaminobenzoic acid in a solvent to obtain a 3,5-diaminobenzoic acid solution;

[0021] b) Add a catalyst to the 3,5-diaminobenzoic acid solution, then raise the temperature to 120 - 150 °C and react for 7 - 9 h. During the reaction, remove the water generated by the reaction through condensation reflux;

[0022] c) Cool the reaction system to 50 - 80 °C, then add ethylenediamine and continue the reaction for 30 - 45 min to obtain a reactant solution;

[0023] d) Drop the reaction product solution into an ether solvent to precipitate the polymer, then filter, wash, and dry to obtain an amino - terminated hyperbranched polymer

[0024] Further, the weight ratio of 3,5 - diamino benzoic acid to ethylenediamine is 1:(0.3 - 0.7).

[0025] Further, benzophenone is grafted onto the amino - terminated hyperbranched polymer, and the grafting method is as follows:

[0026] i. In a toluene solvent, add the amino - terminated hyperbranched polymer and glycidyl methacrylate,

[0027] and add a catalyst, and react at 80 - 100 °C for 8 - 12 h to introduce double bonds onto the hyperbranched polymer to obtain a double - bond - amino - terminated hyperbranched polymer;

[0028] ii. React benzophenone with acryloyl chloride in the presence of triethylamine in dichloromethane to introduce an acryloyl group onto the benzene ring of benzophenone to obtain a double - bond - containing benzophenone compound;

[0029] iii. Mix the double - bond - amino - terminated hyperbranched polymer obtained in i with the double - bond - containing benzophenone compound obtained in ii, then add them together with a radical initiator into an organic solvent, and carry out a radical polymerization reaction at 60 - 80 °C in an inert gas atmosphere;

[0030] iiii. After the reaction, carry out dialysis and freeze - drying to obtain an amino - terminated hyperbranched polymer grafted with benzophenone.

[0031] Further, the weight ratio of benzophenone to the amino - terminated hyperbranched polymer is 1:(6 - 9).

[0032] Further, the ultraviolet absorber is UV - 326.

[0033] In a second aspect, the present application provides a preparation method for preparing a fabric ultraviolet absorber composition, and the following technical solution is adopted.

[0034] A preparation method for a fabric ultraviolet absorber composition, comprising the following steps:

[0035] S1. Mix the ultraviolet absorber, dispersant, defoamer, and water to obtain a pre - dispersion liquid; wherein the dosage of the defoamer is 1 / 2 - 2 / 3 of the total amount of the defoamer;

[0036] S2. Grind the pre-dispersion liquid with the assistance of grinding media;

[0037] S3. After grinding, add the remaining defoamer and centrifuge to remove air bubbles;

[0038] S4. Filter to remove the grinding media to obtain a suspension, and store it sealed and away from light.

[0039] Furthermore, the grinding media is glass beads. By volume, the ratio of glass beads to the pre-dispersion liquid is 1: (2 - 3).

[0040] In summary, the present application has the following beneficial effects:

[0041] In the present application, a hyperbranched polymer and nano-titanium dioxide are compounded as a dispersant. The dispersant molecules are adsorbed on the surface of the ultraviolet absorber particles. During the heat storage process, phase separation or precipitation caused by incompatibility with the medium is avoided, and it can be more evenly dispersed in the medium when heated, reducing performance changes caused by too high or too low local concentration, and improving the heat storage stability. The UPF value of the obtained ultraviolet absorber composition can reach 40+ or even 50+, the ultraviolet transmittance can reach 4.15 - 3.34%, and the change rate of D90 can reach 25.64 - 21.24% after the heat storage time at 80°C changes from 20 min to 40 min. The obtained ultraviolet absorber not only has excellent ultraviolet resistance but also stable heat storage particle size. Detailed implementation manners

[0042] The following further elaborates on the present application with reference to examples.

[0043] Preparation examples of raw materials and intermediates

[0044] Raw materials

[0045] Ultraviolet absorber, UV-326;

[0046] Defoamer, silicone defoamer;

[0047] Nano-titanium dioxide, 200 - 300 nm;

[0048] γ-Glycidoxypropyltrimethoxysilane, analytical pure;

[0049] 3,5 - Diaminobenzoic acid, analytical pure;

[0050] Ethylenediamine, analytical pure;

[0051] Diethyl ether, analytical pure;

[0052] Glycidyl methacrylate, analytical pure;

[0053] Benzophenone, analytical pure;

[0054] Acryloyl chloride, analytical pure;

[0055] Triethylamine, analytical pure;

[0056] Dichloromethane, analytical pure;

[0057] Free radical initiator, azobisisobutyronitrile.

[0058] Preparation Example

[0059] Preparation Example 1

[0060] An amino-terminated hyperbranched polymer, and its preparation method is as follows:

[0061] a) Dissolve 1 kg of 3,5-diaminobenzoic acid in 10 kg of DMSO solvent to obtain a 3,5-diaminobenzoic acid solution; control the dissolution temperature at 45 °C, the magnetic stirring rate at 400 rpm, and the dissolution time at 45 min until the solution becomes clear;

[0062] b) Add 10 g of p-toluenesulfonic acid catalyst to the 3,5-diaminobenzoic acid solution obtained in a), then raise the temperature to 135 °C, carry out condensation reflux under nitrogen protection, and react for 8 h;

[0063] c) Cool the reaction system to 60 °C, then add 0.5 kg of ethylenediamine, and continue to react for 40 min to obtain a reactant solution;

[0064] d) Drop the reaction product solution into an ether solvent at a volume ratio of 1:4, stand for 3 h to precipitate the polymer, then filter, wash 3 times successively with an ethanol-water mixed solution with a volume ratio of 1:1 and pure water to remove unreacted monomers and catalyst residues, and wash and dry to obtain the amino-terminated hyperbranched polymer.

[0065] Preparation Example 2

[0066] The difference from Preparation Example 1 is that the amount of ethylenediamine used in step c) of Preparation Example 2 is 0.3 kg.

[0067] Preparation Example 3

[0068] The difference from Preparation Example 1 is that the amount of ethylenediamine used in step c) of Preparation Example 2 is 0.7 kg.

[0069] Preparation Example 4

[0070] The difference from Preparation Example 1 is that the amount of ethylenediamine used in step c) of Preparation Example 2 is 1.0 kg.

[0071] Preparation Example 5

[0072] A grafted benzophenone amino-terminated hyperbranched polymer, and its preparation method is as follows:

[0073] i. In 55 kg of toluene solvent, 7 kg of amino-terminated hyperbranched polymer and 2 kg of glycidyl methacrylate are added, and 10 g of 4-dimethylaminopyridine catalyst is added. The reaction is carried out at 90 °C for 10 h under nitrogen protection to introduce double bonds onto the hyperbranched polymer, obtaining a double bond-amino-terminated hyperbranched polymer;

[0074] ii. 1 kg of benzophenone is mixed with 0.5 kg of acryloyl chloride, 0.8 kg of triethylamine is added as an acid-binding agent, and the reaction is carried out in 450 kg of dichloromethane solvent to introduce an acryloyl group onto the benzene ring of benzophenone, obtaining a benzophenone compound containing double bonds;

[0075] iii. The double bond-amino-terminated hyperbranched polymer obtained in i and the benzophenone compound containing double bonds obtained in ii are mixed, and then together with 0.5 kg of free radical initiator, they are added to 40 kg of toluene organic solvent. The free radical polymerization reaction is carried out at 70 °C for 8 h under a nitrogen protection gas atmosphere;

[0076] iiii. After the reaction, a dialysis bag with a cut-off molecular weight of 4 kDa is used to dialyze in deionized water for 48 h, changing the water every 4 h, and then freeze-drying to obtain an amino-terminated hyperbranched polymer grafted with benzophenone.

[0077] Preparation Example 6

[0078] Different from Preparation Example 5, in Preparation Example 6, the weight ratio of benzophenone to amino-terminated hyperbranched polymer is 1:6, and the proportions of other raw materials remain unchanged.

[0079] Preparation Example 7

[0080] Different from Preparation Example 5, in Preparation Example 6, the weight ratio of benzophenone to amino-terminated hyperbranched polymer is 1:9, and the proportions of other raw materials remain unchanged.

[0081] Preparation Example 8

[0082] The preparation method of the amino-terminated hyperbranched polymer grafted with nano-titanium dioxide is as follows:

[0083] 1) Pretreatment of nano-titanium dioxide

[0084] 1 kg of nano-titanium dioxide is ultrasonically dispersed in a sodium hydroxide solution with a concentration of 0.5 M, stirred at 80 °C for 2 h, centrifuged, washed with water until neutral, and dried to obtain hydroxyl-nano-titanium dioxide;

[0085] 2) Introduction of active groups

[0086] 1.2 kg of γ-glycidoxypropyltrimethoxysilane and hydroxy-nano titanium dioxide react in 50 L of anhydrous ethanol solvent under nitrogen protection at 70 °C for 12 h, then are centrifuged, washed with ethanol, and dried in vacuum at 60 °C to obtain epoxy-nano titanium dioxide;

[0087] 3) Grafting reaction

[0088] The epoxy-nano titanium dioxide is mixed with 0.5 kg of amino-terminated hyperbranched polymer from Preparation Example 1 in 30 L of toluene solvent, 30 g of triethylamine catalyst is added, and the mixture reacts at 90 °C for 7 h. After the reaction, it is centrifuged and dried in vacuum at 80 °C for 12 h to obtain an amino-terminated hyperbranched polymer grafted with nano titanium dioxide.

[0089] Preparation Example 9

[0090] The difference from Preparation Example 8 is that the amount of amino-terminated hyperbranched polymer used in Preparation Example 9 is 0.7 kg.

[0091] Preparation Example 10

[0092] The difference from Preparation Example 8 is that the amount of amino-terminated hyperbranched polymer used in Preparation Example 10 is 0.8 kg.

[0093] Preparation Examples 11 - 13

[0094] The difference from Preparation Example 8 is that the amino-terminated hyperbranched polymers in Preparation Examples 11 - 13 are respectively from Preparation Examples 2 - 4.

[0095] Preparation Examples 14 - 16

[0096] The difference from Preparation Example 8 is that in Preparation Examples 14 - 16, the amino-terminated hyperbranched polymers are respectively replaced with an equal amount of amino-terminated hyperbranched polymers grafted with benzophenone from Preparation Examples 5 - 7. Examples

[0097] Examples 1 - 3

[0098] A fabric ultraviolet absorber composition, and its preparation method is as follows:

[0099] S1. According to the raw material ratio in Table 1, an ultraviolet absorber, a dispersant, an antifoaming agent, and water are mixed to obtain a pre-dispersed liquid; the amount of the antifoaming agent used is 2 / 3 of the total amount of the antifoaming agent;

[0100] S2. The pre-dispersed liquid is ground with the assistance of glass bead grinding medium, and the ratio of glass beads to the pre-dispersed liquid is 1:3;

[0101] S3. After grinding, the remaining antifoaming agent is added and centrifuged to defoam;

[0102] S4. Filter out the grinding medium to obtain a suspension, and store it sealed and away from light.

[0103] Table 1 Raw material ratio table of Examples 1 - 3 (kg)

[0104]

[0105] Among them, the dispersant is from Preparation Example 8.

[0106] Examples 4 - 11

[0107] Different from Example 2, the dispersants in Examples 4 - 11 are from Preparation Examples 9 - 16 respectively.

[0108] Example 12

[0109] Different from Example 2, in Example 12, an equal amount of benzophenone is directly used as a raw material and mixed with the ultraviolet absorber.

[0110] Comparative Examples

[0111] Comparative Example 1

[0112] Different from Example 1, in Comparative Example 1, the dispersant is an amino - terminated hyperbranched polymer obtained from Preparation Example 1.

[0113] Performance detection

[0114] Referring to "Evaluation of Ultraviolet Protection Performance of Textiles" GB / T 18830—2009, the UPF value and ultraviolet transmittance of the ultraviolet absorber compositions obtained in the examples and comparative examples were detected; in an 80 °C heat storage environment, after 20 min, the heat storage particle size D90 of the ultraviolet absorber composition was tested, and after another 40 min, the heat storage particle size D90 of the ultraviolet absorber composition was tested again, and the D90 change rate was calculated. The D90 change rate = |D90 at 60 min - D90 at 20 min| / D90 at 20 min * 100%. The results are shown in Table 2.

[0115] Table 2 Performance detection results

[0116]

[0117] From Examples 1 - 12 and Comparative Example 1, and in combination with Table 2, it can be seen that the UPF value, ultraviolet transmittance, and heat storage stability of the ultraviolet absorber compositions obtained in Examples 1 - 12 are better than those of Comparative Example 1. This shows that the ultraviolet absorber composition obtained in this application not only has good ultraviolet absorption effect, but also has stable heat storage particle size.

[0118] Combining Example 1 and Comparative Example 1, and referring to Table 2, it can be seen that the difference between Comparative Example 1 and Example 1 lies in the dispersant. The UPF value, ultraviolet transmittance, and thermal storage stability of the ultraviolet absorber composition obtained in Example 1 are all better than those in Comparative Example 1. This shows that the ultraviolet absorber composition obtained in this application not only has good ultraviolet absorption effect, but also has stable particle size during thermal storage. This indicates that the dispersant in this application performs better in improving the absorption effect of the ultraviolet absorber and the stability of the particle size during thermal storage. This may be because the amino-terminated hyperbranched polymer grafted with nano-titanium dioxide is used as the dispersant, and the dispersant molecules are adsorbed on the surface of the ultraviolet absorber particles, preventing the particles from aggregating due to collision during thermal storage and maintaining their good dispersion state. At the same time, the dispersant makes the particles repel each other, maintains the uniform dispersion of the particles, reduces the surface tension between the ultraviolet absorber and the surrounding medium, enables the ultraviolet absorber to be better wetted by water, and plays a bridging role between the ultraviolet absorber and water, promoting the intermolecular interaction between them, and making the ultraviolet absorber better combined with the medium. During thermal storage, it avoids phase separation or precipitation caused by incompatibility with the medium, can be more evenly dispersed in the medium when heated, reduces performance changes caused by too high or too low local concentration, and improves thermal storage stability.

[0119] Combining Example 2 and Examples 9 - 12, and referring to Table 2, it can be seen that the use of benzophenone can improve the ultraviolet absorption effect of the ultraviolet absorber, but grafting benzophenone onto the amino-terminated hyperbranched polymer can further improve the thermal storage stability of the ultraviolet absorber.

[0120] This specific embodiment is only an explanation of this application, and it is not a limitation of this application. Those skilled in the art can make modifications without creative contributions to this embodiment according to needs after reading this specification, but as long as it is within the scope of the claims of this application, it is protected by the patent law.

Claims

1. A fabric ultraviolet absorber composition, characterized in that: The method comprises the following raw materials in parts by weight: 20-50 parts of ultraviolet absorber, 6-13 parts of dispersant, 0.3-0.8 parts of defoamer, and 80-180 parts of water; The dispersant is an amino-terminated hyperbranched polymer grafted with nano-titanium dioxide; The preparation method of the amino-terminated hyperbranched polymer grafted with nano-titanium dioxide is as follows: 1) Pretreatment of nano titanium dioxide The surface of nano-titanium dioxide is treated with a sodium hydroxide solution to introduce hydroxyl groups on the surface of the nano-titanium dioxide to obtain hydroxyl-nano-titanium dioxide; 2) Introducing active groups Using γ-glycidyloxypropyltrimethoxysilane to react with hydroxy-nano titanium dioxide, introducing epoxy groups on the surface of hydroxy-nano titanium dioxide to obtain epoxy-nano titanium dioxide; 3) Grafting reaction The epoxy-nano titanium dioxide and the amino-terminated hyperbranched polymer are mixed in a solvent, reacted at 80-100° C. for 6-8 hours under the action of a catalyst, centrifuged and dried after the reaction to obtain the amino-terminated hyperbranched polymer grafted with nano-titanium dioxide; The weight ratio of the nano titanium dioxide to the amino-terminated hyperbranched polymer is 1:(0.5-0.7); The preparation method of the amino-terminated hyperbranched polymer is: a) dissolving 3,5-diaminobenzoic acid in a solvent to obtain a 3,5-diaminobenzoic acid solution; b) adding a catalyst to the 3,5-diaminobenzoic acid solution, then heating to 120-150° C., reacting for 7-9 hours, and removing the water produced by the reaction by condensation reflux during the reaction; c) cooling the reaction system to 50-80°C, then adding ethylenediamine, and continuing the reaction for 30-45 minutes to obtain a reactant solution; d) adding the reaction product solution dropwise into ether solvent to precipitate the polymer, which is then filtered, washed and dried to obtain an amino-terminated hyperbranched polymer.

2. A fabric ultraviolet absorbent composition according to claim 1, characterized in that: The weight ratio of the 3,5-diaminobenzoic acid to ethylenediamine is 1:(0.3-0.7).

3. A fabric ultraviolet absorbent composition according to claim 1, characterized in that: Benzophenone is grafted onto the amino-terminated hyperbranched polymer, and the grafting method is as follows: i. adding an amino-terminated hyperbranched polymer and glycidyl methacrylate to a toluene solvent, A catalyst is added, and the reaction is carried out at 80-100° C. for 8-12 hours to introduce double bonds into the hyperbranched polymer to obtain a double bond-amino terminated hyperbranched polymer; ii. reacting benzophenone with acryloyl chloride in the presence of triethylamine in dichloromethane to introduce an acryloyl group into the benzene ring of benzophenone to obtain a benzophenone compound containing a double bond; iii. The double bond-amino-terminated hyperbranched polymer obtained in i and the double bond-containing benzophenone compound obtained in ii are mixed, and then added to an organic solvent together with a free radical initiator, and a free radical polymerization reaction is carried out at 60 - 80 ° C in a protective gas atmosphere; iiii. After the reaction, the product was dialyzed and freeze-dried to obtain an amino-terminated hyperbranched polymer grafted with benzophenone.

4. A fabric ultraviolet absorbent composition according to claim 3, characterized in that: The weight ratio of the benzophenone to the amino-terminated hyperbranched polymer is 1:(6-9).

5. A fabric ultraviolet absorbent composition according to claim 3, characterized in that: The ultraviolet absorber is UV-326.

6. A preparation method for preparing the fabric ultraviolet absorbent composition according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. The ultraviolet absorber, dispersant, defoamer and water are mixed to obtain a pre-dispersion; wherein the amount of the defoamer is 1 / 2-2 / 3 of the total amount of the defoamer; S2. The pre-dispersed liquid is ground with the aid of a grinding medium; S3. After grinding, add the remaining defoamer and centrifuge to degas; S4. Filter to remove the grinding medium to obtain a suspension, which is then sealed and stored away from light.

7. A preparation method according to claim 6, characterized in that: The grinding medium is glass beads, and the ratio of glass beads to pre-dispersion liquid is 1: (2-3) by volume.

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