Unsaturated resin putty with adjustable curing speed and preparation method thereof

Abstract

The invention discloses unsaturated resin putty with an adjustable curing speed and a preparation method thereof, and relates to the technical field of coatings. The unsaturated resin putty capable of adjusting the curing speed is prepared from hyperbranched modified unsaturated polyester resin, a temperature-sensitive speed regulation additive, a curing agent, styrene, magnesium oxide, nano calcium carbonate and titanium dioxide. The temperature-sensitive speed regulation additive is composed of a temperature-sensitive response gel material, a curing accelerator and a curing accelerator liquid; the unsaturated resin putty prepared by adding the temperature-sensitive speed-regulating additive, hyperbranched modified unsaturated polyester resin and other auxiliaries has temperature-sensitive responsiveness, releases more curing promoting components at low temperature, reduces release at high temperature, can autonomously regulate curing time under different temperature conditions, strengthens the curing effect at the same time, and has a good application prospect. The flexibility and the impact resistance are improved, and the service life of the putty material is prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings, and specifically refers to an unsaturated resin putty with adjustable curing speed and a preparation method thereof. Background Art

[0002] Powder coating is a new type of solid environmentally friendly coating that is different from traditional solvent-based coatings. Powder coating does not use any solvents in the preparation process and has the characteristics of no pollution, stable storage, easy transportation, resource saving and high efficiency. It can be used in household appliances, pipeline anti-corrosion, automobile and other industries. Among them, the main component of unsaturated polyester putty is a thermosetting resin, which has the characteristics of low price, simple production process, high transparency, etc. It can adapt well to the process of powder electrostatic spraying and is widely used in powder coatings.

[0003] Unsaturated resin putty, commonly known as atomic putty, is a common unsaturated resin putty on the market. It is composed of polyester resin, filler, curing agent, thickener and other components. It is constructed in proportion when used and corresponds to a fixed curing time at a certain temperature. Before this, it can be constructed and scraped. After this time, it will solidify and cannot be used. With the changes in temperature, the time for construction will also fluctuate greatly. The construction time will be shortened when the temperature is high and the construction time will be extended when the temperature is low. Therefore, the amount of curing agent can be adjusted according to the temperature changes in different seasons to adjust the curing time.

[0004] The existing technology currently has the following problems:

[0005] There are no products on the market that can adjust the curing time autonomously with temperature changes. In order to meet the requirements of construction coating time at different construction temperatures, products with different construction times have to be produced separately into ultra-fast drying, fast drying, medium drying, slow drying, ultra-slow drying and other models. The products produced in this way have specific seasons or ranges of use, and have poor flexibility in use, which is not conducive to convenient use by users. Summary of the invention

[0006] In view of the above situation, in order to overcome the defects of the prior art, the present invention proposes an unsaturated resin putty with adjustable curing speed, comprising the following components in parts by weight: 60-80 parts of hyperbranched modified unsaturated polyester resin, 20-30 parts of temperature-sensitive speed regulating additive, 6-8 parts of curing agent, 1-5 parts of styrene, 3-5 parts of magnesium oxide, 10-20 parts of nano calcium carbonate, and 20-30 parts of titanium dioxide.

[0007] The temperature-sensitive speed-regulating additive comprises the following components in parts by weight: 30-40 parts of a temperature-sensitive response gel material, 10-20 parts of a curing accelerator, and 10-15 parts of a curing accelerator liquid.

[0008] The temperature-sensitive response gel material is a temperature-sensitive copolymer hydrogel prepared by front-end polymerization method with N-isopropylacrylamide and maleic acid as copolymer monomers.

[0009] The curing accelerator comprises the following components in parts by weight: 5-10 parts of maleic anhydride and 5-10 parts of nano titanium dioxide.

[0010] The curing agent is one or more of benzoyl peroxide, cyclohexanone peroxide and TGIC.

[0011] The preparation method of the temperature-sensitive speed regulating additive specifically comprises the following steps:

[0012] (1) N-isopropylacrylamide, maleic acid, crosslinking agent N,N-dimethylbisacrylamide and initiator ammonium persulfate were dissolved in 10 mL of deionized water. In the solution, the mass fraction of maleic acid was 10.0-15.0%, the mass fraction of N,N-dimethylbisacrylamide was 0.5%, and the mass fraction of ammonium persulfate was 1.0%. The solution was dissolved by ultrasonic and stirring. The reaction solution was poured into a special test tube with a scale, and a K-type thermocouple was inserted. The outer periphery of the test tube of the upper layer solution was heated with an electric soldering iron to initiate the reaction. After the local reaction formed a stable polymer front, the heat source was removed. The polymer front was a polymerization area of ​​1-3 mm wide. The reaction was continued until the spontaneous reaction was completely carried out. After the reaction was completed, the gel was taken out, cut into pieces, and soaked in deionized water for 24 hours to remove the unreacted substances and dried. The copolymer hydrogel prepared by the front polymerization method with N-isopropylacrylamide as the main monomer and maleic acid as the second monomer had low temperature sensitivity. As the temperature decreased, the water absorption and swelling ability gradually increased, and a thermosensitive responsive gel material was obtained.

[0013] (2) heating maleic anhydride and nano titanium dioxide at 60-70°C to melt the maleic anhydride, stirring at a stirring speed of 600-800 rpm for 20-30 minutes, cooling to room temperature, first crushing with a mesh size of 60-80 mesh, and then ultrafine grinding with a mesh size of 100-300 mesh. The modification treatment with maleic anhydride enhances the dispersibility of nano titanium dioxide and reduces its agglomeration, which is conducive to better exerting the curing effect and toughening and strengthening of nano titanium dioxide in promoting the polyester resin. At the same time, maleic anhydride can also react with the active groups of the polyester resin to promote the cross-linking and curing of the resin, further enhancing the curing promotion of the resin to obtain a curing accelerator;

[0014] (3) Add the curing accelerator liquid to the thermosensitive responsive gel material described in step (1), stir magnetically for 5-10 minutes, then add the curing accelerator described in step (2), stir for 20-30 minutes, and then homogenize under high pressure, with a homogenization pressure of 600-800 bar and a homogenization time of 1-3 minutes. The thermosensitive responsive gel material is used as a carrier to carry the dual-action substances of the curing accelerator and the curing accelerator liquid. Through the responsive release of the carrier to different temperatures, more action substances are released at low temperatures, and less action substances are released at high temperatures, thereby realizing self-regulation of the curing time of the resin and obtaining a temperature-sensitive speed regulating additive.

[0015] Preferably, in step (1), the mass ratio of N-isopropylacrylamide to maleic acid is (7-9):1, and controlling the amount ratio of the monomers is beneficial to the movement rate of the polymerization front end and shortening the reaction time;

[0016] Preferably, in step (3), the curing accelerator is m-xylylenediamine, which can promote the reaction between functional groups such as hydroxyl groups in the polyester resin and isocyanate groups, thereby promoting the curing of the resin.

[0017] The present invention also provides a method for preparing an unsaturated resin putty with adjustable curing speed, which specifically comprises the following steps:

[0018] S1, add 300g of hyperbranched resin H101, 360g of benzoic acid and 3.0g of p-toluenesulfonic acid into a 2L round-bottom flask equipped with a mechanical stirring device, a thermometer, a water separator and a nitrogen inlet, slowly heat up to 150-160°C under nitrogen protection, react for 1-3h, during which the acid value of the resin does not change, vacuum react for 1-3h, during which the acid value of the resin does not change, the hyperbranched resin has a special spherical structure, contains side chains and functional groups, can provide good leveling, adhesion, impact resistance, etc. for the resin coating, and thus also has a positive effect on the flexibility of the coating, to obtain a hyperbranched resin H101BA;

[0019] S2, 4g neopentyl glycol, 6g terephthalic acid, 0.5g adipic acid and 0.1-0.7g of the hyperbranched resin H101BA described in step S1, and 20mg of the catalyst monobutyl tin oxide are added in sequence to a 2L round-bottom flask equipped with a mechanical stirring device, a thermometer, a water separator, and a nitrogen inlet, and the temperature is slowly raised to 225-245°C under nitrogen protection, and kept warm for 3-4h, the acid value is controlled at 12-14mgKOH / g, and the temperature is lowered to 230°C, 1g of the acidolysis agent isophthalic acid is added, and the temperature is kept at 230°C for 3-4h. 5h, control the acid value at 42-46mgKOH / g, evacuate until the acid value drops to 31-33mgKOH / g, cool to 210°C, then add triphenylethylphosphonium bromide, and stir for 20min. The polyester resin modified by hyperbranching has excellent heat resistance and corrosion resistance, and can maintain long-term stability in harsh environments such as high temperature and strong acid. At the same time, it also has good fluidity and flexibility in low temperature environments, further optimizing the low-temperature curing performance of the coating, and obtaining a hyperbranched modified unsaturated polyester resin;

[0020] S3, the hyperbranched modified unsaturated polyester resin, temperature-sensitive speed-regulating additive, curing agent, styrene, magnesium oxide, nano-calcium carbonate and titanium dioxide described in step S2 are pre-mixed by a high-speed disperser at a rotation speed of 300-500rpm and a mixing time of 10-20min, and then melt-extruded and pressed into sheets by a twin-screw extruder, and then crushed by a multifunctional pulverizer. The addition of the temperature-sensitive speed-regulating additive can absorb and retain a large amount of water, which plays a catalytic role in the curing process of the polyester resin and promotes the cross-linking reaction of the polyester resin. The gel structure has a certain mechanical strength, which helps to provide a certain support and stability when the polyester resin is cured, prevents the polyester resin from deforming or shrinking during the curing process, and effectively improves flexibility and impact resistance. The temperature-sensitive speed-regulating additive can autonomously adjust the curing accelerator and curing accelerator liquid to release the load through different swelling rates under low and high temperature environments. The synergistic effect of the two solid and liquid substances improves the effectiveness and uniformity of the curing effect, and also helps to improve the impact resistance, thereby obtaining an unsaturated resin putty with adjustable curing speed;

[0021] Preferably, in step S2, the amount of triphenylethylphosphonium bromide added is 0.1-0.2 g, and triphenylethylphosphonium bromide can improve the curing performance of the resin and is also conducive to enhancing the impact resistance;

[0022] Preferably, in step S3, the aperture of the sieve during pulverization is 100-200 meshes, which ensures the uniformity of the particle size of the powder coating and helps to uniformly cure the putty.

[0023] The beneficial effects achieved by the present invention are as follows:

[0024] The unsaturated resin putty prepared by adding a temperature-sensitive speed-regulating additive and a hyperbranched modified unsaturated polyester resin and other auxiliary agents has temperature-sensitive responsiveness, releases more curing-promoting components at low temperatures, reduces the release at high temperatures, can autonomously adjust the curing time under different temperature conditions, and at the same time, strengthens the curing effect, improves the flexibility and impact resistance, and prolongs the service life of the putty material; in the temperature-sensitive speed-regulating additive, a temperature-sensitive responsive gel material is used as a carrier, which carries a curing promoter and a curing promoter liquid, and responds to release dual curing promoters through the high swelling of the carrier at low temperatures and the low swelling of the carrier at high temperatures, and can autonomously adjust the curing time, and the gel structure catalyzes the curing process of the polyester resin by absorbing moisture, and also provides certain support and stability for the curing of the resin, improves the flexibility and impact resistance, and improves the curing effect, wherein the curing promoter is a composite formed by maleic anhydride and nano-titanium dioxide, both of which can promote the cross-linking of the resin. The maleic anhydride component can improve the compatibility and dispersibility of each component, which has a positive effect on the pore uniformity and swelling performance of the gel structure, and further enhances the durability of the resin curing; the hyperbranched modified unsaturated polyester resin introduces the hyperbranched resin H101BA, which has certain stability and heat resistance, and can also maintain good fluidity at low temperatures, which is helpful to improve flexibility and impact resistance and enhance the curing effect. At the same time, due to its hyperbranched and stable spherical structure, it can reduce crosslinking with the gel material, which is beneficial to ensure the swelling performance of the gel structure; the present invention uses the hyperbranched modified unsaturated polyester resin, the temperature-sensitive speed regulating additive, the curing agent, the styrene, the magnesium oxide, the nano calcium carbonate and the titanium dioxide to prepare an unsaturated resin putty with adjustable curing speed, which can independently adjust the curing time, improve the convenience of use, and also improve the flexibility and impact resistance of the putty after curing, and extend the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a scanning electron microscope image of the temperature-sensitive speed-regulating additive prepared in Example 1 of the present invention;

[0026] Figure 2 This is a scanning electron microscope image of a cross section of an unsaturated resin putty with adjustable curing speed prepared in Example 1 of the present invention;

[0027] Figure 3 The swelling rate-temperature relationship curve of the thermosensitive responsive gel material prepared in Example 1 of the present invention;

[0028] Figure 4 It is a graph showing the curing time results of Examples 1-4 and Comparative Examples 1-3 of the present invention;

[0029] Figure 5It is a graph showing the mechanical properties of Examples 1-4 of the present invention and Comparative Examples 1-3. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0031] Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein may be applied to the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only and are not intended to limit the content of this application.

[0032] The experimental methods in the following examples are conventional methods unless otherwise specified; the experimental materials used in the following examples are purchased from commercial channels unless otherwise specified.

[0033] TGICCASNo:2451-62-9, Brand: Innochem, Product No.: A80326;

[0034] Benzoyl peroxide CAS No: 94-36-0, brand Innochem, product number A98034;

[0035] Cyclohexanone peroxide CAS No: 12262-58-7, brand Macklin, product number C805295-100g;

[0036] Styrene CAS No: 100-42-5, brand Innochem, product number A56356;

[0037] Magnesium oxide CAS No: 1309-48-4, brand Innochem, product number A04327;

[0038] Nano calcium carbonate CAS No: 471-34-1, brand Innochem, product number C6800;

[0039] Titanium dioxide brand: CITIC Titanium, item number: CR211;

[0040] N-isopropylacrylamide CAS No: 2210-25-5, brand Innochem, product number A49861;

[0041] Maleic acid CAS No: 110-16-7, brand Innochem, product number A15550;

[0042] N,N-dimethylbisacrylamide CAS No: 110-26-9, brand Sigma-Aldrich, product number 146072;

[0043] Ammonium persulfate CAS No: 7727-54-0, brand Innochem, product number A68367;

[0044] Maleic anhydride CAS No: 108-31-6, brand Innochem, product number A28939;

[0045] Nano titanium dioxide CAS No: 13463-67-7, brand Innochem, product number A02033;

[0046] Meta-phenylenediamine CAS No: 1477-55-0, brand Innochem, product number A56796;

[0047] Hyperbranched resin H101 brand Wuhan Hyperbranched Resin Technology Co., Ltd., item number H101;

[0048] Benzoic acid CAS No: 65-85-0, brand Innochem, product number A70585;

[0049] p-Toluenesulfonic acid CAS No: 104-15-4, brand Innochem, product number A94068;

[0050] Neopentyl glycol CAS No: 126-30-7, brand Innochem, product number A57404;

[0051] Terephthalic acid CAS No: 100-21-0, brand Innochem, product number A68313;

[0052] Adipic acid CAS No: 124-04-9, brand Innochem, product number A33263;

[0053] Isophthalic acid CAS No: 121-91-5, brand Alfa, product number A14445;

[0054] Triphenylethylphosphonium bromide CAS No: 1530-32-1, brand Innochem, product number A44131.

[0055] Example 1

[0056] This embodiment proposes an unsaturated resin putty with adjustable curing speed, comprising the following components in parts by weight: 80 parts of hyperbranched modified unsaturated polyester resin, 30 parts of temperature-sensitive speed regulating additive, 8 parts of benzoyl peroxide curing agent, 5 parts of styrene, 5 parts of magnesium oxide, 20 parts of nano-calcium carbonate, and 30 parts of titanium dioxide.

[0057] The temperature-sensitive speed-regulating additive comprises the following components in parts by weight: 40 parts of temperature-sensitive response gel material, 20 parts of curing accelerator, and 15 parts of curing accelerator liquid.

[0058] The thermosensitive responsive gel material is a thermosensitive copolymer hydrogel prepared by a front-end polymerization method using N-isopropylacrylamide and maleic acid as copolymer monomers.

[0059] The curing accelerator comprises the following components in parts by weight: 10 parts of maleic anhydride and 10 parts of nano titanium dioxide.

[0060] The preparation method of the temperature-sensitive speed regulating additive specifically comprises the following steps:

[0061] (1) Dissolve N-isopropylacrylamide, maleic acid, crosslinker N,N-dimethylbisacrylamide and initiator ammonium persulfate in 10 mL of deionized water. In the solution, the mass fraction of maleic acid is 15.0%, the mass fraction of N,N-dimethylbisacrylamide is 0.5%, the mass fraction of ammonium persulfate is 1.0%, and the mass ratio of N-isopropylacrylamide to maleic acid is 9:1. Controlling the amount ratio of the monomers is beneficial to the migration rate of the polymerization front and shortening the reaction time. Dissolve by ultrasonication and stirring. Pour the reaction solution into a special test tube with a scale and insert K A thermocouple is used to heat the outer side of the test tube of the upper solution with an electric soldering iron to induce a reaction. After the local reaction forms a stable polymer front end, the heat source is removed, wherein the polymer front end is a polymerization area with a width of 1-3 mm, until the spontaneous reaction is completely carried out. After the reaction is completed, the gel is taken out, cut into pieces, and soaked in deionized water for 24 hours to remove unreacted substances and dry. The copolymer hydrogel prepared by the front-end polymerization method with N-isopropylacrylamide as the main monomer and maleic acid as the second monomer has low-temperature sensitivity. As the temperature decreases, the water absorption and swelling ability gradually increases, and a temperature-sensitive response gel material is obtained;

[0062] (2) Heating maleic anhydride and nano-titanium dioxide at 70°C to melt the maleic anhydride, stirring at a stirring speed of 800 rpm for 30 minutes, cooling to room temperature, first crushing with a sieve aperture of 80 mesh, and then ultrafine grinding with a sieve aperture of 300 mesh. The modification treatment with maleic anhydride enhances the dispersibility of nano-titanium dioxide and reduces its agglomeration phenomenon, which is conducive to better exerting the curing effect and toughening and strengthening of nano-titanium dioxide on polyester resin. At the same time, maleic anhydride can also react with the active groups of polyester resin to promote the cross-linking and curing of the resin, further enhancing the curing promotion of the resin to obtain a curing accelerator;

[0063] (3) Adding a curing accelerator liquid to the thermosensitive responsive gel material described in step (1), wherein the curing accelerator liquid is m-xylylenediamine, which can promote the reaction of functional groups such as hydroxyl groups in the polyester resin with isocyanate groups, thereby promoting the curing of the resin. The mixture is stirred magnetically for 10 minutes, and then the curing accelerator described in step (2) is added. The mixture is stirred for 30 minutes, and then high-pressure homogenization is performed. The homogenization pressure is 800 bar and the homogenization time is 3 minutes. The thermosensitive responsive gel material is used as a carrier to carry the dual-action substances of the curing accelerator and the curing accelerator liquid. The carrier releases more action substances at low temperatures and reduces the release of action substances at high temperatures through the carrier's responsive release to different temperatures, thereby achieving autonomous adjustment of the curing time of the resin and obtaining a temperature-sensitive speed regulating additive.

[0064] This embodiment provides a method for preparing an unsaturated resin putty with adjustable curing speed, which specifically comprises the following steps:

[0065] S1, 300g of hyperbranched resin H101, 360g of benzoic acid and 3.0g of p-toluenesulfonic acid were added to a 2L round-bottom flask equipped with a mechanical stirring device, a thermometer, a water separator and a nitrogen inlet, and the temperature was slowly raised to 160°C under nitrogen protection, and the reaction was carried out for 3h, during which the acid value of the resin did not change, and the reaction was carried out under vacuum for 3h, during which the acid value of the resin did not change. The hyperbranched resin has a special spherical structure, contains side chains and functional groups, and can provide the resin coating with good leveling, adhesion, impact resistance, etc., thereby also having a positive effect on the flexibility of the coating, and obtaining the hyperbranched resin H101BA;

[0066] S2, 4g neopentyl glycol, 6g terephthalic acid, 0.5g adipic acid and 0.7g hyperbranched resin H101BA described in step S1, and 20mg catalyst monobutyl tin oxide are added in sequence to a 2L round-bottom flask equipped with a mechanical stirring device, a thermometer, a water separator, and a nitrogen inlet, and the temperature is slowly raised to 245°C under nitrogen protection, and kept warm for 4h, and the acid value is controlled at 12-14mgKOH / g, and the temperature is lowered to 230°C, 1g acidolysis agent isophthalic acid is added and kept warm at 230°C for 5h, and the acid value is controlled at 42-46mgKOH / g, and vacuum is evacuated until the acid value drops to 31 -33mgKOH / g, cooling to 210°C, then adding triphenylethylphosphonium bromide, the addition amount of triphenylethylphosphonium bromide is 0.2g, triphenylethylphosphonium bromide can improve the curing performance of the resin, and is also conducive to enhancing the impact resistance, stirring for 20 minutes, the polyester resin modified by hyperbranching has excellent heat resistance and corrosion resistance, can maintain long-term stability in harsh environments such as high temperature and strong acid, and at the same time, it also has good fluidity and flexibility in low temperature environments, further optimizing the low-temperature curing performance of the coating, and obtaining a hyperbranched modified unsaturated polyester resin;

[0067] S3, the hyperbranched modified unsaturated polyester resin, temperature-sensitive speed-regulating additive, benzoyl peroxide curing agent, styrene, magnesium oxide, nano-calcium carbonate and titanium dioxide described in step S2 are pre-mixed by a high-speed disperser at a speed of 500 rpm and a mixing time of 20 min, then melt-extruded and pressed into tablets by a twin-screw extruder, and then crushed by a multifunctional pulverizer, the mesh aperture during crushing is 200 mesh, to ensure the uniformity of the particle size of the powder coating, which helps to uniformly cure the putty, and the addition of the temperature-sensitive speed-regulating additive can absorb and retain a large amount of water, which plays a role in the curing process of the polyester resin. The catalytic effect promotes the cross-linking reaction of the polyester resin. The gel structure has a certain mechanical strength, which helps to provide a certain support and stability when the polyester resin is cured, prevents the polyester resin from deforming or shrinking during the curing process, and effectively improves flexibility and impact resistance. The temperature-sensitive speed regulating additive can autonomously adjust the release of the loaded curing promoter and curing promoter liquid through different swelling rates under low and high temperature environments. The synergistic effect of the two substances, solid and liquid, improves the effectiveness and uniformity of the curing effect, and also helps to improve the impact resistance, thereby obtaining an unsaturated resin putty with adjustable curing speed.

[0068] In this embodiment, the cross section of the prepared temperature-sensitive speed-regulating additive and the unsaturated resin putty with adjustable curing speed is subjected to scanning electron microscopy to observe its microscopic morphology, and the temperature-sensitive response gel material in the temperature-sensitive speed-regulating additive is tested for 5 minutes of swelling performance. Figure 1 This is a SEM image of the temperature-sensitive speed-regulating additive prepared in Example 1, magnified 200 times. Figure 2This is a SEM image of the cross section of the unsaturated resin putty with adjustable curing speed prepared in Example 1, magnified 400 times. Figure 3 The swelling rate-temperature relationship curve of the thermosensitive responsive gel material prepared in Example 1 is shown in FIG. Figure 1 The temperature-sensitive speed-regulating additive prepared in this embodiment is a loaded gel structure, such as Figure 2 The unsaturated resin putty with adjustable curing speed prepared in this embodiment exhibits good dispersion compatibility in the cross section, such as Figure 3 The temperature-sensitive responsive gel material prepared in this embodiment has the responsiveness of high swelling at low temperature and low swelling at high temperature.

[0069] Example 2

[0070] This embodiment proposes an unsaturated resin putty with adjustable curing speed, comprising the following components in parts by weight: 60 parts of hyperbranched modified unsaturated polyester resin, 20 parts of temperature-sensitive speed regulating additive, 6 parts of cyclohexanone peroxide curing agent, 1 part of styrene, 3 parts of magnesium oxide, 10 parts of nano-calcium carbonate, and 20 parts of titanium dioxide.

[0071] The temperature-sensitive speed-regulating additive comprises the following components in parts by weight: 30 parts of temperature-sensitive response gel material, 10 parts of curing accelerator, and 10 parts of curing accelerator liquid.

[0072] The thermosensitive responsive gel material is a thermosensitive copolymer hydrogel prepared by a front-end polymerization method using N-isopropylacrylamide and maleic acid as copolymer monomers.

[0073] The curing accelerator comprises the following components in parts by weight: 5 parts of maleic anhydride and 5 parts of nano titanium dioxide.

[0074] The preparation method of the temperature-sensitive speed regulating additive specifically comprises the following steps:

[0075] (1) Dissolve N-isopropylacrylamide, maleic acid, crosslinker N,N-dimethylbisacrylamide and initiator ammonium persulfate in 10 mL of deionized water. In the solution, the mass fraction of maleic acid is 10.0%, the mass fraction of N,N-dimethylbisacrylamide is 0.5%, the mass fraction of ammonium persulfate is 1.0%, and the mass ratio of N-isopropylacrylamide to maleic acid is 7:1. Controlling the amount ratio of the monomers is beneficial to the migration rate of the polymerization front and shortening the reaction time. Dissolve by ultrasonication and stirring. Pour the reaction solution into a special test tube with a scale and insert K A thermocouple is used to heat the outer side of the test tube of the upper solution with an electric soldering iron to induce a reaction. After the local reaction forms a stable polymer front end, the heat source is removed, wherein the polymer front end is a polymerization area with a width of 1-3 mm, until the spontaneous reaction is completely carried out. After the reaction is completed, the gel is taken out, cut into pieces, and soaked in deionized water for 24 hours to remove unreacted substances and dry. The copolymer hydrogel prepared by the front-end polymerization method with N-isopropylacrylamide as the main monomer and maleic acid as the second monomer has low-temperature sensitivity. As the temperature decreases, the water absorption and swelling ability gradually increases, and a temperature-sensitive response gel material is obtained;

[0076] (2) Heating maleic anhydride and nano-titanium dioxide at 60°C to melt the maleic anhydride, stirring at a stirring speed of 600 rpm for 20 minutes, cooling to room temperature, first crushing with a sieve aperture of 60 mesh, and then ultrafine grinding with a sieve aperture of 100 mesh. The modification treatment with maleic anhydride enhances the dispersibility of nano-titanium dioxide and reduces its agglomeration phenomenon, which is conducive to better exerting the curing effect and toughening and strengthening of nano-titanium dioxide in promoting the polyester resin. At the same time, maleic anhydride can also react with the active groups of the polyester resin to promote the cross-linking and curing of the resin, further enhancing the curing promotion of the resin to obtain a curing accelerator;

[0077] (3) Adding a curing accelerator liquid to the thermosensitive responsive gel material described in step (1), wherein the curing accelerator liquid is m-xylylenediamine, which can promote the reaction of functional groups such as hydroxyl groups in the polyester resin with isocyanate groups, thereby promoting the curing of the resin. The mixture is stirred magnetically for 5 minutes, and then the curing accelerator described in step (2) is added. The mixture is stirred for 20 minutes, and then high-pressure homogenization is performed. The homogenization pressure is 600 bar and the homogenization time is 1 minute. The thermosensitive responsive gel material is used as a carrier, which carries the dual-action substances of the curing accelerator and the curing accelerator liquid. The carrier releases more action substances at low temperatures and reduces the release of action substances at high temperatures through the carrier's responsive release to different temperatures, thereby realizing autonomous adjustment of the curing time of the resin and obtaining a temperature-sensitive speed regulating additive.

[0078] This embodiment provides a method for preparing an unsaturated resin putty with adjustable curing speed, which specifically comprises the following steps:

[0079] S1, 300g of hyperbranched resin H101, 360g of benzoic acid and 3.0g of p-toluenesulfonic acid were added to a 2L round-bottom flask equipped with a mechanical stirring device, a thermometer, a water separator and a nitrogen inlet, and the temperature was slowly raised to 150°C under nitrogen protection, and the reaction was carried out for 1h, during which the acid value of the resin did not change, and the reaction was carried out under vacuum for 1h, during which the acid value of the resin did not change. The hyperbranched resin has a special spherical structure, contains side chains and functional groups, and can provide the resin coating with good leveling, adhesion, impact resistance, etc., thereby also having a positive effect on the flexibility of the coating, and obtaining the hyperbranched resin H101BA;

[0080] S2, 4g neopentyl glycol, 6g terephthalic acid, 0.5g adipic acid and 0.1g hyperbranched resin H101BA described in step S1, and 20mg catalyst monobutyl tin oxide are added in sequence to a 2L round-bottom flask equipped with a mechanical stirring device, a thermometer, a water separator, and a nitrogen inlet, and the temperature is slowly raised to 225°C under nitrogen protection, and kept warm for 3h, and the acid value is controlled at 12-14mgKOH / g, and the temperature is lowered to 230°C, 1g acidolysis agent isophthalic acid is added and kept warm at 230°C for 3h, and the acid value is controlled at 42-46mgKOH / g, and vacuum is evacuated until the acid value drops to 31 -33mgKOH / g, cooling to 210°C, then adding triphenylethylphosphonium bromide, the addition amount of triphenylethylphosphonium bromide is 0.1g, triphenylethylphosphonium bromide can improve the curing performance of the resin, and is also conducive to enhancing the impact resistance, stirring for 20 minutes, the polyester resin modified by hyperbranching has excellent heat resistance and corrosion resistance, can maintain long-term stability in harsh environments such as high temperature and strong acid, and at the same time, it also has good fluidity and flexibility in low temperature environments, further optimizing the low-temperature curing performance of the coating, and obtaining a hyperbranched modified unsaturated polyester resin;

[0081] S3, the hyperbranched modified unsaturated polyester resin, temperature-sensitive speed-regulating additive, cyclohexanone peroxide curing agent, styrene, magnesium oxide, nano-calcium carbonate and titanium dioxide described in step S2 are pre-mixed by a high-speed disperser at a speed of 300 rpm and a mixing time of 10 min, and then melt-extruded and pressed into tablets by a twin-screw extruder, and then crushed by a multifunctional crusher, the mesh aperture during crushing is 100 mesh, to ensure the uniformity of the particle size of the powder coating, which is conducive to the uniform curing of the putty. The addition of the temperature-sensitive speed-regulating additive can absorb and retain a large amount of water, which plays a role in the curing process of the polyester resin. The catalytic effect promotes the cross-linking reaction of the polyester resin. The gel structure has a certain mechanical strength, which helps to provide a certain support and stability when the polyester resin is cured, prevents the polyester resin from deforming or shrinking during the curing process, and effectively improves flexibility and impact resistance. The temperature-sensitive speed regulating additive can autonomously adjust the release of the loaded curing promoter and curing promoter liquid through different swelling rates under low and high temperature environments. The synergistic effect of the two substances, solid and liquid, improves the effectiveness and uniformity of the curing effect, and also helps to improve the impact resistance, thereby obtaining an unsaturated resin putty with adjustable curing speed.

[0082] Example 3

[0083] This embodiment proposes an unsaturated resin putty with adjustable curing speed, comprising the following components in parts by weight: 70 parts of hyperbranched modified unsaturated polyester resin, 25 parts of temperature-sensitive speed regulating additive, 7 parts of TGIC curing agent, 3 parts of styrene, 4 parts of magnesium oxide, 15 parts of nano-calcium carbonate, and 25 parts of titanium dioxide.

[0084] The temperature-sensitive speed regulating additive comprises the following components in parts by weight: 35 parts of temperature-sensitive response gel material, 15 parts of curing accelerator, and 12.5 parts of curing accelerator liquid.

[0085] The thermosensitive responsive gel material is a thermosensitive copolymer hydrogel prepared by a front-end polymerization method using N-isopropylacrylamide and maleic acid as copolymer monomers.

[0086] The curing accelerator comprises the following components in parts by weight: 7.5 parts of maleic anhydride and 7.5 parts of nano titanium dioxide.

[0087] The preparation method of the temperature-sensitive speed regulating additive specifically comprises the following steps:

[0088] (1) Dissolve N-isopropylacrylamide, maleic acid, crosslinker N,N-dimethylbisacrylamide and initiator ammonium persulfate in 10 mL of deionized water. In the solution, the mass fraction of maleic acid is 12.5%, the mass fraction of N,N-dimethylbisacrylamide is 0.5%, the mass fraction of ammonium persulfate is 1.0%, and the mass ratio of N-isopropylacrylamide to maleic acid is 8:1. Controlling the amount ratio of the monomers is beneficial to the migration rate of the polymerization front and shortening the reaction time. Dissolve by ultrasonication and stirring. Pour the reaction solution into a special test tube with a scale and insert K A thermocouple is used to heat the outer side of the test tube of the upper solution with an electric soldering iron to induce a reaction. After the local reaction forms a stable polymer front end, the heat source is removed, wherein the polymer front end is a polymerization area with a width of 1-3 mm, until the spontaneous reaction is completely carried out. After the reaction is completed, the gel is taken out, cut into pieces, and soaked in deionized water for 24 hours to remove unreacted substances and dry. The copolymer hydrogel prepared by the front-end polymerization method with N-isopropylacrylamide as the main monomer and maleic acid as the second monomer has low-temperature sensitivity. As the temperature decreases, the water absorption and swelling ability gradually increases, and a temperature-sensitive response gel material is obtained;

[0089] (2) Heating maleic anhydride and nano-titanium dioxide at 65°C to melt the maleic anhydride, stirring at a stirring speed of 700 rpm for 25 minutes, cooling to room temperature, first crushing with a sieve aperture of 70 mesh, and then ultrafine grinding with a sieve aperture of 200 mesh. The modification treatment with maleic anhydride enhances the dispersibility of nano-titanium dioxide and reduces its agglomeration phenomenon, which is conducive to better exerting the curing effect and toughening and strengthening of nano-titanium dioxide on polyester resin. At the same time, maleic anhydride can also react with the active groups of polyester resin to promote the cross-linking and curing of the resin, further enhancing the curing promotion of the resin to obtain a curing accelerator;

[0090] (3) Adding a curing accelerator liquid to the thermosensitive responsive gel material described in step (1), wherein the curing accelerator liquid is m-xylylenediamine, which can promote the reaction of functional groups such as hydroxyl groups in the polyester resin with isocyanate groups, thereby promoting the curing of the resin. The mixture is stirred magnetically for 7.5 minutes, and then the curing accelerator described in step (2) is added. The mixture is stirred for 25 minutes, and then high-pressure homogenization is performed. The homogenization pressure is 700 bar and the homogenization time is 2 minutes. The thermosensitive responsive gel material is used as a carrier to carry the dual-action substances of the curing accelerator and the curing accelerator liquid. The carrier releases more action substances at low temperatures and reduces the release of action substances at high temperatures through the carrier's responsive release to different temperatures, thereby achieving autonomous adjustment of the curing time of the resin and obtaining a temperature-sensitive speed regulating additive.

[0091] This embodiment provides a method for preparing an unsaturated resin putty with adjustable curing speed, which specifically comprises the following steps:

[0092] S1, 300g of hyperbranched resin H101, 360g of benzoic acid and 3.0g of p-toluenesulfonic acid were added to a 2L round-bottom flask equipped with a mechanical stirring device, a thermometer, a water separator and a nitrogen inlet, and the temperature was slowly raised to 155°C under nitrogen protection, and the reaction was carried out for 2h, during which the acid value of the resin did not change, and the reaction was carried out under vacuum for 2h, during which the acid value of the resin did not change. The hyperbranched resin has a special spherical structure, contains side chains and functional groups, and can provide the resin coating with good leveling, adhesion, impact resistance, etc., thereby also having a positive effect on the flexibility of the coating, and obtaining the hyperbranched resin H101BA;

[0093] S2, 4g neopentyl glycol, 6g terephthalic acid, 0.5g adipic acid and 0.4g hyperbranched resin H101BA described in step S1, and 20mg catalyst monobutyl tin oxide are added in sequence to a 2L round-bottom flask equipped with a mechanical stirring device, a thermometer, a water separator, and a nitrogen inlet, and the temperature is slowly raised to 235°C under nitrogen protection, and the temperature is kept for 3.5h to control the acid value at 12-14mgKOH / g, and the temperature is lowered to 230°C, 1g acidolysis agent isophthalic acid is added and the temperature is kept at 230°C for 4h to control the acid value at 42-46mgKOH / g, and the mixture is evacuated until the acid value drops to 31 -33mgKOH / g, cooling to 210°C, then adding triphenylethylphosphonium bromide, the addition amount of triphenylethylphosphonium bromide is 0.15g, triphenylethylphosphonium bromide can improve the curing performance of the resin, and is also conducive to enhancing the impact resistance, stirring for 20 minutes, the polyester resin modified by hyperbranching has excellent heat resistance and corrosion resistance, can maintain long-term stability in harsh environments such as high temperature and strong acid, and at the same time, it also has good fluidity and flexibility in low temperature environments, further optimizing the low-temperature curing performance of the coating, and obtaining a hyperbranched modified unsaturated polyester resin;

[0094] S3, the hyperbranched modified unsaturated polyester resin, temperature-sensitive speed-regulating additive, TGIC curing agent, styrene, magnesium oxide, nano-calcium carbonate and titanium dioxide described in step S2 are pre-mixed in a high-speed disperser at a speed of 400 rpm and a mixing time of 15 min, and then melt-extruded and pressed into tablets through a twin-screw extruder, and then crushed using a multifunctional crusher, the mesh aperture during crushing is 150 mesh, to ensure the uniformity of the particle size of the powder coating, which is conducive to the uniform curing of the putty. The addition of the temperature-sensitive speed-regulating additive can absorb and retain a large amount of water, which plays a role in the curing process of the polyester resin. It has a catalytic effect and promotes the cross-linking reaction of the polyester resin. The gel structure has a certain mechanical strength, which helps to provide a certain support and stability when the polyester resin is cured, prevents the polyester resin from deforming or shrinking during the curing process, and effectively improves flexibility and impact resistance. In addition, the temperature-sensitive speed-regulating additive can autonomously adjust the release of the loaded curing promoter and curing promoter liquid through different swelling rates under low and high temperature environments. The synergistic effect of the two substances, solid and liquid, improves the effectiveness and uniformity of the curing effect, and also helps to improve the impact resistance, thereby obtaining an unsaturated resin putty with adjustable curing speed.

[0095] Example 4

[0096] This embodiment proposes an unsaturated resin putty with adjustable curing speed, comprising the following components in parts by weight: 80 parts of hyperbranched modified unsaturated polyester resin, 20 parts of temperature-sensitive speed regulating additive, 6 parts of curing agent, 5 parts of styrene, 5 parts of magnesium oxide, 20 parts of nano-calcium carbonate, and 30 parts of titanium dioxide.

[0097] The temperature-sensitive speed-regulating additive comprises the following components in parts by weight: 30 parts of temperature-sensitive response gel material, 20 parts of curing accelerator, and 15 parts of curing accelerator liquid.

[0098] The thermosensitive responsive gel material is a thermosensitive copolymer hydrogel prepared by a front-end polymerization method using N-isopropylacrylamide and maleic acid as copolymer monomers.

[0099] The curing accelerator comprises the following components in parts by weight: 5 parts of maleic anhydride and 10 parts of nano titanium dioxide.

[0100] The curing agent comprises the following components in parts by weight: 2 parts of benzoyl peroxide, 2 parts of cyclohexanone peroxide, and 2 parts of TGIC.

[0101] The preparation method of the temperature-sensitive speed regulating additive specifically comprises the following steps:

[0102] (1) Dissolve N-isopropylacrylamide, maleic acid, crosslinker N,N-dimethylbisacrylamide and initiator ammonium persulfate in 10 mL of deionized water. In the solution, the mass fraction of maleic acid is 10.0%, the mass fraction of N,N-dimethylbisacrylamide is 0.5%, the mass fraction of ammonium persulfate is 1.0%, and the mass ratio of N-isopropylacrylamide to maleic acid is 9:1. Controlling the amount ratio of the monomers is beneficial to the migration rate of the polymerization front and shortening the reaction time. Dissolve by ultrasonication and stirring. Pour the reaction solution into a special test tube with a scale and insert K A thermocouple is used to heat the outer side of the test tube of the upper solution with an electric soldering iron to induce a reaction. After the local reaction forms a stable polymer front end, the heat source is removed, wherein the polymer front end is a polymerization area with a width of 1-3 mm, until the spontaneous reaction is completely carried out. After the reaction is completed, the gel is taken out, cut into pieces, and soaked in deionized water for 24 hours to remove unreacted substances and dry. The copolymer hydrogel prepared by the front-end polymerization method with N-isopropylacrylamide as the main monomer and maleic acid as the second monomer has low-temperature sensitivity. As the temperature decreases, the water absorption and swelling ability gradually increases, and a temperature-sensitive response gel material is obtained;

[0103] (2) Heating maleic anhydride and nano-titanium dioxide at 70°C to melt the maleic anhydride, stirring at a stirring speed of 800 rpm for 20 minutes, cooling to room temperature, first crushing with a sieve aperture of 80 mesh, and then ultrafine grinding with a sieve aperture of 300 mesh. The modification treatment with maleic anhydride enhances the dispersibility of nano-titanium dioxide and reduces its agglomeration phenomenon, which is conducive to better exerting the curing effect and toughening and strengthening of nano-titanium dioxide on polyester resin. At the same time, maleic anhydride can also react with the active groups of polyester resin to promote the cross-linking and curing of the resin, further enhancing the curing promotion of the resin to obtain a curing accelerator;

[0104] (3) Adding a curing accelerator liquid to the thermosensitive responsive gel material described in step (1), wherein the curing accelerator liquid is m-xylylenediamine, which can promote the reaction of functional groups such as hydroxyl groups in the polyester resin with isocyanate groups, thereby promoting the curing of the resin. The mixture is stirred magnetically for 5 minutes, and then the curing accelerator described in step (2) is added. The mixture is stirred for 20 minutes, and then high-pressure homogenization is performed. The homogenization pressure is 800 bar and the homogenization time is 1 minute. The thermosensitive responsive gel material is used as a carrier, which carries the dual-action substances of the curing accelerator and the curing accelerator liquid. The carrier releases more action substances at low temperatures and reduces the release of action substances at high temperatures through the carrier's responsive release to different temperatures, thereby realizing autonomous adjustment of the curing time of the resin and obtaining a temperature-sensitive speed regulating additive.

[0105] This embodiment provides a method for preparing an unsaturated resin putty with adjustable curing speed, which specifically comprises the following steps:

[0106] S1, 300g of hyperbranched resin H101, 360g of benzoic acid and 3.0g of p-toluenesulfonic acid were added to a 2L round-bottom flask equipped with a mechanical stirring device, a thermometer, a water separator and a nitrogen inlet, and the temperature was slowly raised to 160°C under nitrogen protection, and the reaction was carried out for 1h, during which the acid value of the resin did not change, and the reaction was carried out under vacuum for 1h, during which the acid value of the resin did not change. The hyperbranched resin has a special spherical structure, contains side chains and functional groups, and can provide the resin coating with good leveling, adhesion, impact resistance, etc., thereby also having a positive effect on the flexibility of the coating, and obtaining the hyperbranched resin H101BA;

[0107] S2, 4g neopentyl glycol, 6g terephthalic acid, 0.5g adipic acid and 0.1g hyperbranched resin H101BA described in step S1, and 20mg catalyst monobutyl tin oxide are added in sequence to a 2L round-bottom flask equipped with a mechanical stirring device, a thermometer, a water separator, and a nitrogen inlet, and the temperature is slowly raised to 245°C under nitrogen protection, and kept warm for 3h, and the acid value is controlled at 12-14mgKOH / g, and the temperature is lowered to 230°C, 1g acidolysis agent isophthalic acid is added and kept warm at 230°C for 3h, and the acid value is controlled at 42-46mgKOH / g, and vacuum is evacuated until the acid value drops to 31 -33mgKOH / g, cooling to 210°C, then adding triphenylethylphosphonium bromide, the addition amount of triphenylethylphosphonium bromide is 0.2g, triphenylethylphosphonium bromide can improve the curing performance of the resin, and is also conducive to enhancing the impact resistance, stirring for 20 minutes, the polyester resin modified by hyperbranching has excellent heat resistance and corrosion resistance, can maintain long-term stability in harsh environments such as high temperature and strong acid, and at the same time, it also has good fluidity and flexibility in low temperature environments, further optimizing the low-temperature curing performance of the coating, and obtaining a hyperbranched modified unsaturated polyester resin;

[0108] S3, the hyperbranched modified unsaturated polyester resin, temperature-sensitive speed-regulating additive, curing agent, styrene, magnesium oxide, nano-calcium carbonate and titanium dioxide described in step S2 are pre-mixed by a high-speed disperser at a speed of 500 rpm and a mixing time of 10 min, and then melt-extruded and pressed into tablets by a twin-screw extruder, and then crushed by a multifunctional pulverizer, the mesh aperture during crushing is 200 mesh, to ensure the uniformity of the particle size of the powder coating, which is conducive to the uniform curing of the putty. The addition of the temperature-sensitive speed-regulating additive can absorb and retain a large amount of water, and the water plays a catalytic role in the curing process of the polyester resin. The chemical reaction promotes the cross-linking reaction of the polyester resin. The gel structure has a certain mechanical strength, which helps to provide a certain support and stability when the polyester resin is cured, prevents the polyester resin from deforming or shrinking during the curing process, and effectively improves the flexibility and impact resistance. The temperature-sensitive speed-regulating additive can independently adjust the release of the loaded curing promoter and curing promoter liquid through different swelling rates under low and high temperature environments. The synergistic effect of the two substances, solid and liquid, improves the effectiveness and uniformity of the curing effect, and also helps to improve the impact resistance, thereby obtaining an unsaturated resin putty with adjustable curing speed.

[0109] Comparative Example 1

[0110] This comparative example provides an unsaturated resin putty with adjustable curing speed, which differs from Example 1 in that the temperature-sensitive speed regulating additive does not contain a temperature-sensitive responsive gel material; the preparation method of the temperature-sensitive speed regulating additive does not include step (1); and the preparation method of the unsaturated resin putty with adjustable curing speed is the same as that of Example 1.

[0111] Comparative Example 2

[0112] This comparative example provides an unsaturated resin putty with adjustable curing speed, which differs from Example 1 in that the temperature-sensitive speed regulating additive does not contain maleic anhydride; the preparation method of the temperature-sensitive speed regulating additive is the same as that of Example 1; and the preparation method of the unsaturated resin putty with adjustable curing speed is the same as that of Example 1.

[0113] Comparative Example 3

[0114] This comparative example provides an unsaturated resin putty with adjustable curing speed, which differs from Example 1 in that the hyperbranched modified unsaturated polyester resin does not contain hyperbranched resin H101BA; the preparation method of the temperature-sensitive speed regulating additive is the same as that of Example 1; and the preparation method of the unsaturated resin putty with adjustable curing speed does not include step S1.

[0115] Experimental Example 1

[0116] Curing time experiment

[0117] Test sample: unsaturated resin putty with adjustable curing speed prepared in Examples 1-4 and Comparative Examples 1-3.

[0118] Test method: Test the curing time of the test samples at 5℃, 20℃ and 35℃ respectively according to GB / T1728-2020.

[0119] Figure 4 It is a result diagram of the curing time of Examples 1-4 and Comparative Examples 1-3; as shown in the figure, the curing time of Examples 1-4 at 5°C, 20°C, and 35°C are 2-2.3h, 1.5-1.8h, and 1-1.3h, respectively, indicating that the curing time can be adjusted independently to adapt to different temperatures; the curing time of Comparative Examples 1-3 at 5°C, 20°C, and 35°C are 2.7-3h, 2.2-2.5h, and 1.5-1.8h, respectively, indicating that the self-adjustability of the curing time at different temperatures is poor; the temperature-sensitive speed regulating additive of Comparative Example 1 does not contain a temperature-sensitive responsive gel material, and cannot respond to release a dual curing promoter, resulting in a curing time at different temperatures. The self-adjustability is poor; the temperature-sensitive speed-regulating additive of Comparative Example 2 does not contain maleic anhydride, which is not conducive to the pore uniformity of the gel structure and has an adverse effect on its swelling performance, thereby reducing the release amount at different temperatures. At the same time, it also increases the agglomeration of nano-titanium dioxide, which is not conducive to the cross-linking and curing of the resin, resulting in poor self-adjustability of the curing time at different temperatures; the hyperbranched modified unsaturated polyester resin of Comparative Example 3 does not contain hyperbranched resin H101BA, lacks a stable group structure, increases the cross-linking of the resin and the gel structure, and has an adverse effect on the swelling performance of the gel structure, resulting in poor self-adjustability of the curing time at different temperatures.

[0120] Experimental Example 2

[0121] Mechanical properties test

[0122] Test sample: unsaturated resin putty with adjustable curing speed prepared in Examples 1-4 and Comparative Examples 1-3.

[0123] Test method: After the test sample is cured at room temperature, flexibility and impact resistance tests are performed. The flexibility is tested in accordance with GB / T1731-2020, and the impact resistance is tested in accordance with GB / T1732-2020.

[0124] Figure 5It is a graph of the mechanical properties of Examples 1-4 and Comparative Examples 1-3; as shown in the figure, the flexibility and impact resistance of Examples 1-4 are 25-50mm and 45-50cm, respectively, indicating that the flexibility and impact resistance are good; the flexibility and impact resistance of Comparative Examples 1-3 are 5-15mm and 25-30cm, respectively, indicating that the flexibility and impact resistance are average; the temperature-sensitive speed-regulating additive of Comparative Example 1 does not contain a temperature-sensitive response gel material, and cannot provide support and stability for the curing of the resin, resulting in average flexibility and impact resistance; the temperature-sensitive speed-regulating additive of Comparative Example 2 does not contain maleic anhydride, which is not conducive to the dispersion and compatibility of the components, nor is it conducive to better exerting the toughening and strengthening effect of nano titanium dioxide, resulting in average flexibility and impact resistance; the hyperbranched modified unsaturated polyester resin of Comparative Example 3 does not contain a hyperbranched resin H101BA, does not have good fluidity and stability, weakens the curing effect, and results in average flexibility and impact resistance.

[0125] The above experimental results show that the adjustability of the curing time and the mechanical properties of Examples 1-4 of the present invention are significantly better than those of the samples of Comparative Examples 1-3. Among them, the adjustability of the curing time of Example 1 using a temperature-sensitive speed regulating additive and a hyperbranched modified unsaturated polyester resin is better, and the flexibility and impact resistance are better. The temperature-sensitive responsive gel material is used as a carrier, and a curing accelerator and a curing accelerator liquid are loaded. Through the high swelling of the carrier at low temperature and the low swelling at high temperature, the dual curing accelerator is released in response, and the autonomous adjustment of the curing time is achieved. The gel structure also provides certain support and stability for the curing of the resin, and improves the flexibility and impact resistance. The modification of maleic anhydride in the curing accelerator reduces the aggregation of nano-titanium dioxide, and the maleic anhydride component can also improve the compatibility and dispersibility of each component, which not only has a positive effect on the pore uniformity and swelling performance of the gel structure, but also further enhances the resin curing effect. The hyperbranched modified unsaturated polyester resin with the hyperbranched resin H101BA has certain stability and heat resistance, and can maintain good fluidity at low temperatures, which is helpful to improve the flexibility and impact resistance of the resin after curing. At the same time, due to its hyperbranched and stable spherical structure, it can reduce the cross-linking with the gel material, which is beneficial to ensure the swelling performance of the gel structure.

[0126] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that many changes, modifications, substitutions and variations can be made to the embodiments without departing from the principles and spirit of the invention.

[0127] The present invention and its implementation methods are described above, which is not restrictive. The drawings are only one of the implementation methods of the present invention, and the actual application is not limited thereto. In short, if ordinary technicians in the field are inspired by it and design methods and embodiments similar to the technical solution without creativity without departing from the purpose of the invention, they should all fall within the protection scope of the present invention.

Claims

1. An unsaturated resin putty with adjustable curing speed, characterized in that: The unsaturated resin putty with adjustable curing speed comprises the following components in parts by weight: 60-80 parts of hyperbranched modified unsaturated polyester resin, 20-30 parts of temperature-sensitive speed regulating additive, 6-8 parts of curing agent, 1-5 parts of styrene, 3-5 parts of magnesium oxide, 10-20 parts of nano calcium carbonate, and 20-30 parts of titanium dioxide; the temperature-sensitive speed regulating additive comprises the following components in parts by weight: 30-40 parts of temperature-sensitive response gel material, 10-20 parts of curing accelerator, and 10-15 parts of curing accelerator liquid; the temperature-sensitive response gel material is a temperature-sensitive copolymer hydrogel prepared by front-end polymerization method with N-isopropylacrylamide and maleic acid as copolymer monomers; the curing accelerator comprises the following components in parts by weight: 5-10 parts of maleic anhydride and 5-10 parts of nano titanium dioxide; the curing agent is one or more of benzoyl peroxide, cyclohexanone peroxide, and TGIC.

2. A method for preparing an unsaturated resin putty with adjustable curing speed according to claim 1, characterized in that: The specific steps include: S1, 300g of hyperbranched resin H101, 360g of benzoic acid and 3.0g of p-toluenesulfonic acid were added to a 2L round-bottom flask equipped with a mechanical stirrer, a thermometer, a water separator and a nitrogen inlet, and the temperature was slowly raised to 150-160°C under nitrogen protection, and the reaction was performed for 1-3h, during which the acid value of the resin did not change, and the reaction was performed under vacuum for 1-3h, during which the acid value of the resin did not change, to obtain a hyperbranched resin H101BA; S2, 4g neopentyl glycol, 6g terephthalic acid, 0.5g adipic acid and 0.1-0.7g of the hyperbranched resin H101BA described in step S1, and 20mg of the catalyst monobutyl tin oxide are sequentially added into a 2L round-bottom flask equipped with a mechanical stirring device, a thermometer, a water separator, and a nitrogen inlet, and the temperature is slowly raised to 225-245°C under nitrogen protection, and kept warm for 3-4h, the acid value is controlled at 12-14mgKOH / g, and the temperature is lowered to 230°C, 1g of an acidolysis agent isophthalic acid is added and kept warm at 230°C for 3-5h, the acid value is controlled at 42-46mgKOH / g, and vacuumized until the acid value drops to 31-33mgKOH / g, and the temperature is lowered to 210°C, and then triphenylethylphosphonium bromide is added, and stirred for 20min to obtain a hyperbranched modified unsaturated polyester resin; S3, the hyperbranched modified unsaturated polyester resin, temperature-sensitive speed regulating additive, curing agent, styrene, magnesium oxide, nano-calcium carbonate and titanium dioxide described in step S2 are pre-mixed with a high-speed disperser at a speed of 300-500rpm and a mixing time of 10-20min, then melt-extruded and sheeted with a twin-screw extruder, and then pulverized with a multifunctional pulverizer to obtain an unsaturated resin putty with adjustable curing speed.

3. The method for preparing an unsaturated resin putty with adjustable curing speed according to claim 2, characterized in that: In step S2, the amount of triphenylethylphosphonium bromide added is 0.1-0.2 g.

4. The method for preparing an unsaturated resin putty with adjustable curing speed according to claim 3, characterized in that: In step S3, the mesh size of the sieve during pulverization is 100-200 meshes.

5. The method for preparing an unsaturated resin putty with adjustable curing speed according to claim 4, characterized in that: The preparation method of the temperature-sensitive speed regulating additive specifically comprises the following steps: (1) N-isopropylacrylamide, maleic acid, crosslinking agent N,N-dimethylbisacrylamide and initiator ammonium persulfate were dissolved in 10 mL of deionized water. In the solution, the mass fraction of maleic acid was 10.0-15.0%, the mass fraction of N,N-dimethylbisacrylamide was 0.5%, and the mass fraction of ammonium persulfate was 1.0%. The solution was dissolved by ultrasonic and stirring. The reaction solution was poured into a special test tube with a scale, and a K-type thermocouple was inserted. The outer periphery of the test tube of the upper solution was heated with an electric soldering iron to initiate the reaction. After the local reaction formed a stable polymer front, the heat source was removed, wherein the polymer front was a polymerization area of ​​1-3 mm wide, until the spontaneous reaction was completely carried out. After the reaction was completed, the gel was taken out, cut into pieces, and soaked in deionized water for 24 h to remove the unreacted substances, and dried to obtain a thermosensitive responsive gel material; (2) heating maleic anhydride and nano-titanium dioxide at 60-70°C to melt the maleic anhydride, stirring at a stirring speed of 600-800 rpm for 20-30 minutes, cooling to room temperature, first crushing with a sieve aperture of 60-80 mesh, and then ultrafine grinding with a sieve aperture of 100-300 mesh to obtain a curing accelerator; (3) Add the curing accelerator liquid to the thermosensitive responsive gel material described in step (1), stir magnetically for 5-10 minutes, then add the curing accelerator described in step (2), stir for 20-30 minutes, and then homogenize under high pressure at a homogenization pressure of 600-800 bar and a homogenization time of 1-3 minutes to obtain a temperature-sensitive speed regulating additive.

6. The method for preparing an unsaturated resin putty with adjustable curing speed according to claim 5, characterized in that: In step (1), the mass ratio of N-isopropylacrylamide to maleic acid is 7-9:

1.

7. The method for preparing an unsaturated resin putty with adjustable curing speed according to claim 6, characterized in that: In step (3), the curing accelerating liquid is m-xylylenediamine.

Images