A high-temperature resistant composite material for hot stamping rollers and its preparation method

Abstract

This application relates to the field of fluororubber composite materials technology, and discloses a high-temperature resistant composite material for hot stamping rollers and its preparation method. By weight, it comprises the following raw materials: high molecular weight fluororubber raw rubber: 40-60 parts; low molecular weight fluororubber raw rubber: 60-40 parts; boron nitride nanosheets: 10-20 parts; tetrafluoroethylene-propylene copolymer: 5-10 parts; magnesium oxide: 2-5 parts; diamine vulcanizing agent: 1.5-2.5 parts; accelerator: 0.5-1.5 parts. In this application, through the synergistic effect of the above raw materials, the high-temperature resistant composite material for hot stamping rollers can possess excellent high-temperature resistance, corrosion resistance, and wear resistance, while also maintaining elastic recovery properties, enabling it to operate stably in the high-temperature environment of processes such as cigarette tipping paper production, cigarette pack hot stamping, and laser film anti-counterfeiting.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fluororubber composite materials, and particularly relates to a high-temperature-resistant composite material for a gilding roller and a preparation method thereof. BACKGROUND

[0002] In the processes of cigarette tipping paper, cigarette package gilding, laser film anti-counterfeiting, etc., the gilding roller plays a crucial role. It needs to withstand high temperature, high pressure and various chemical substances. However, traditional roller materials such as nitrile rubber and silicone rubber are prone to softening, deformation, aging and other problems in high-temperature environments, resulting in uneven gilding pressure, poor gilding effect, and even shortening the service life of the roller. In addition, some traditional roller materials will release volatile organic compounds (VOCs) at high temperatures, which poses a potential threat to the production environment and the health of operators. Therefore, developing a gilding roller material with excellent high-temperature resistance, chemical stability and long service life is of great significance for improving gilding quality, reducing production costs and protecting the environment. Although some high-temperature-resistant materials have been applied to roller manufacturing in the prior art, they are high in cost or have deficiencies in chemical corrosion resistance, elasticity and other aspects, which cannot meet the needs of high-end applications such as cigarette package gilding and laser film anti-counterfeiting. Therefore, the prior art still needs to be improved and developed. SUMMARY

[0003] In view of the deficiencies of the prior art, the present application aims to provide a high-temperature-resistant composite material for a gilding roller and a preparation method thereof, which is suitable for processes such as cigarette tipping paper, cigarette package gilding, laser film anti-counterfeiting, etc.

[0004] The technical solution of the present application is as follows:

[0005] A high-temperature-resistant composite material for a gilding roller, wherein the following raw materials are included in terms of weight fraction:

[0006] High molecular weight fluororubber raw rubber: 40-60 parts;

[0007] Low molecular weight fluororubber raw rubber: 60-40 parts;

[0008] Boron nitride nanosheet: 10-20 parts;

[0009] Tetrafluoroethylene-propylene copolymer: 5-10 parts;

[0010] Magnesium oxide: 2-5 parts;

[0011] Diamine curing agent: 1.5-2.5 parts;

[0012] Accelerator: 0.5-1.5 parts.

[0013] In the scheme, through the synergistic effect of the above raw materials, the gilding roller resistant high temperature composite material has excellent high temperature resistance, corrosion resistance and wear resistance, and also has elastic recovery performance, so that it can work stably in the high temperature environment of cigarette tipping paper, cigarette package gilding, laser film anti-counterfeiting process and the like.

[0014] The gilding roller resistant high temperature composite material, wherein the gilding roller resistant high temperature composite material further comprises the following raw materials in terms of weight fraction:

[0015] The ethylene-methyl acrylate copolymer accounts for 1-5% of the total mass of the high molecular weight fluororubber raw rubber and the low molecular weight fluororubber raw rubber;

[0016] The dicumyl peroxide accounts for 0.5-2% of the mass of the ethylene-methyl acrylate copolymer.

[0017] The gilding roller resistant high temperature composite material, wherein the gilding roller resistant high temperature composite material further comprises the following raw materials in terms of weight fraction:

[0018] The fluorocarbon surfactant is 0.5-1.5 parts by weight.

[0019] The gilding roller resistant high temperature composite material, wherein the mass ratio of the high molecular weight fluororubber raw rubber to the low molecular weight fluororubber raw rubber is 1:1.

[0020] The gilding roller resistant high temperature composite material, wherein the high molecular weight fluororubber raw rubber is Viton E60C, and the low molecular weight fluororubber raw rubber is Viton E45.

[0021] The accelerator is Viton Curative VC-50.

[0022] The gilding roller resistant high temperature composite material, wherein the boron nitride nanosheet has a particle size range of 30-100 nm.

[0023] The gilding roller resistant high temperature composite material, wherein the magnesium oxide is light magnesium oxide.

[0024] The gilding roller resistant high temperature composite material, wherein the diamine type vulcanizing agent is 2-aminoethyl aminocaproic acid or di(orthoamino)phenyl disulfide.

[0025] A preparation method of the gilding roller resistant high temperature composite material, comprising the following steps:

[0026] Mixing the high molecular weight fluororubber raw rubber and the low molecular weight fluororubber raw rubber uniformly to obtain a fluororubber raw rubber mixture;

[0027] The boron nitride nanosheet and the tetrafluoroethylene-propylene copolymer are added into the fluorine rubber raw rubber mixture in batches and mixed uniformly, the magnesium oxide, the diamine curing agent and the accelerator are added and mixed uniformly to obtain a mixed rubber;

[0028] The mixed rubber is subjected to a tabletting operation, and the thickness of the rubber tablet is controlled to be 2-10 mm;

[0029] The rubber tablet is subjected to vulcanization: vulcanization at 160-170 DEG C for 20-30 minutes, and then the temperature is increased to 185-195 DEG C, and vulcanization is performed for 2.5-3.5 hours.

[0030] The preparation method of the high-temperature-resistant composite material for the gold stamping rubber roller, wherein when the raw material of the high-temperature-resistant composite material for the gold stamping rubber roller further comprises ethylene-methyl acrylate copolymer and dicumyl peroxide, the following steps are further included before the boron nitride nanosheet and the tetrafluoroethylene-propylene copolymer are added:

[0031] The ethylene-methyl acrylate copolymer, the dicumyl peroxide and the fluorine rubber raw rubber mixture are mixed uniformly;

[0032] When the raw material of the high-temperature-resistant composite material for the gold stamping rubber roller further comprises fluorocarbon surfactant, the fluorocarbon surfactant is added simultaneously with the boron nitride nanosheet and the tetrafluoroethylene-propylene copolymer;

[0033] Before the tabletting operation of the mixed rubber is performed, the following step is further included:

[0034] The mixed rubber is subjected to open mixing for 5-10 minutes, and then the roller temperature is adjusted to be 25-35 DEG C, and mixing is performed for 3-5 minutes.

[0035] Compared with the prior art, the high-temperature-resistant composite material for the gold stamping rubber roller has the following beneficial effects: the high-temperature-resistant composite material for the gold stamping rubber roller has excellent high-temperature resistance, corrosion resistance and wear resistance, and simultaneously has elastic recovery performance, so that it can stably work in a high-temperature environment of a process such as cigarette tipping paper, cigarette package gold stamping, laser film anti-counterfeiting and the like. DETAILED DESCRIPTION

[0036] In order to facilitate the understanding of the present application, the present application lists the following embodiments. It should be understood by those skilled in the art that the embodiments are only used to facilitate the understanding of the present application, and should not be regarded as a specific limitation on the present application.

[0037] The present application provides a high-temperature-resistant composite material for a gold stamping rubber roller, which comprises the following raw materials according to weight fractions:

[0038] High-molecular-weight fluorine rubber raw rubber: 40-60 parts;

[0039] Low molecular weight fluoroelastomer raw rubber: 60-40 parts;

[0040] Boron nitride nanosheet: 10-20 parts;

[0041] Tetrafluoroethylene-propylene copolymer: 5-10 parts;

[0042] Magnesium oxide: 2-5 parts;

[0043] Diamine curing agent: 1.5-2.5 parts;

[0044] Accelerator: 0.5-1.5 parts.

[0045] In the scheme of the present application, the fluoroelastomer molecular chain contains a large number of C-F bonds, which have a very high bond energy, so that it is not easy to break at high temperature. The fluoroelastomer raw rubber uses two different molecular weight fluoroelastomer raw rubbers as the base material, the fluoroelastomer with higher molecular weight can improve the strength and wear resistance of the rubber roller, and the fluoroelastomer with lower molecular weight can improve the elastic recovery performance of the high-temperature-resistant composite material for gold stamping roller. By adjusting the molecular weight and crosslinking density of the fluoroelastomer, the elastic recovery performance of the rubber roller can be optimized, and the gold stamping precision can be improved. Boron nitride nanosheet has a hexagonal crystal structure, and the layered structure makes it have good high-temperature resistance and thermal conductivity, which can effectively disperse heat and reduce the temperature gradient inside the high-temperature-resistant composite material for gold stamping roller. The self-lubricating property of tetrafluoroethylene-propylene copolymer can reduce the friction coefficient of the surface of the high-temperature-resistant composite material for gold stamping roller and reduce wear. Magnesium oxide can react with fluorine atoms in the fluoroelastomer raw rubber to form MgF2, which plays a crosslinking role and improves the strength and elasticity of the high-temperature-resistant composite material for gold stamping roller. Magnesium oxide can also significantly improve the heat resistance (long-term resistance to 200℃ or above) and corrosion resistance (especially to acidic media) of the high-temperature-resistant composite material for gold stamping roller through the triple mechanism of thermal stability enhancement, acid absorption protection, and thermal decomposition inhibition. In addition, magnesium oxide can also neutralize acidic gases or acidic inks that may be generated during the gold stamping process, protect the fluoroelastomer matrix from corrosion, and improve the corrosion resistance of the rubber roller. The diamine curing agent is used to effectively crosslink the fluoroelastomer raw rubber, thereby obtaining ideal heat resistance and compression deformation resistance, which can provide excellent heat resistance and compression deformation resistance. The accelerator can accelerate the vulcanization reaction, shorten the vulcanization time, and improve the production efficiency.

[0046] The fluoroelastomer raw rubber can be selected from Viton A series, Viton B series, Viton GF series, Viton E series, etc. In the embodiment scheme of the present application, the high molecular weight fluoroelastomer raw rubber is Viton E60C, and the low molecular weight fluoroelastomer raw rubber is Viton E45, both of which are from DuPont Company, and the mass ratio of high molecular weight fluoroelastomer raw rubber to low molecular weight fluoroelastomer raw rubber is 1:1.

[0047] The boron nitride nanosheet is selected from boron nitride nanosheets with different particle sizes and purities, the particle size range is 30-100 nm, the purity is not less than 99%, and the most preferred boron nitride nanosheet has an average particle size of 50 nm and a purity of 99.5%, has good dispersibility, and has a significant enhancement effect. In the embodiment of the present application, the average particle size of the boron nitride nanosheet is 50 nm, and the purity is 99.5%, and the source is Beijing Dikai Nanometer Technology Co., Ltd.

[0048] The tetrafluoroethylene-propylene copolymer can be selected from Atlas 100, JSR Atlas, FE2701, and the most preferred is FE2701, which has good wear resistance and lubricity. In the embodiment of the present application, the tetrafluoroethylene-propylene copolymer is selected from FE2701, and the source is Shanghai Sanai Fu.

[0049] The magnesium oxide can be selected from light magnesium oxide or active magnesium oxide, and the most preferred is light magnesium oxide, which has good dispersibility and activation effect.

[0050] The diamine curing agent can be selected from 2-aminoethyl carbamic acid, di(orthoamino)phenyl disulfide, etc., and the most preferred is 2-aminoethyl carbamic acid, which is from Hubei Jianmo.

[0051] The accelerator can be selected from Viton Curative VC series, and the most preferred is Viton Curative VC-50, which is from DuPont.

[0052] In the present application, through the synergistic effect of the above raw materials, the high-temperature-resistant composite material for gilding roller has excellent high-temperature resistance, corrosion resistance and wear resistance, while considering the elastic recovery performance, so that it can work stably in the high-temperature environment of gilding cigarette gilding, laser film anti-counterfeiting process. Compared with the prior art, the present formulation scheme has the following advantages:

[0053] 1. Fluorine rubber is used as the base material, which has excellent high-temperature resistance and chemical corrosion resistance, can effectively prevent the glue layer from softening, deforming and decomposing at high temperature. And by adjusting the proportion of fluorine rubber raw rubber with different molecular weights, the Shore hardness (Shore A hardness can reach more than 95) and elastic recovery performance of the high-temperature-resistant composite material for gilding roller are optimized.

[0054] 2. Adding boron nitride nanosheet as high-temperature-resistant filler can significantly improve the high-temperature resistance and thermal conductivity of the high-temperature-resistant composite material for gilding roller, and the boron nitride nanosheet can also significantly improve the wear resistance and service life of the high-temperature-resistant composite material for gilding roller.

[0055] 3. Adding tetrafluoroethylene-propylene copolymer as lubricant can reduce the friction coefficient of the glue layer, improve the wear resistance, and reduce the replacement frequency.

[0056] 4. The use of magnesium oxide as an acid absorbent improves the corrosion resistance of the rubber roller. Magnesium oxide can also promote the vulcanization reaction of the raw fluororubber, improving the strength and elasticity of the rubber layer.

[0057] 5. Optimizing the formula and preparation process can improve the uniformity and density of the high-temperature-resistant composite material for gilding rubber rollers, further improving its high-temperature resistance and mechanical strength, and improving the overall performance and service life of the high-temperature-resistant composite material for gilding rubber rollers.

[0058] 6. Through the synergistic effect between the components, the problems of swelling, hardening, and cracking of existing fluororubber rubber rollers in the process of gilding cigarette packets, laser film anti-counterfeiting, and other processes are effectively solved.

[0059] Although two different molecular weight raw fluororubbers are selected for mixing to adjust the Shore hardness and elastic recovery performance of the rubber roller, in actual application, due to the differences in molecular structure and polarity between the two types of fluororubbers, compatibility problems may occur, leading to a decrease in the mechanical properties of the rubber roller, and even delamination. Therefore, the high-temperature-resistant composite material for gilding rubber rollers according to the present application further comprises the following raw materials in weight percentage:

[0060] Ethylene-methyl acrylate copolymer (EMA): 1%-5% of the total mass of raw fluororubber;

[0061] Dicumyl peroxide (DCP): 0.5%-2% of the mass of EMA.

[0062] The optional range of EMA is Lotryl series, Evatane series, etc. In the embodiment of the present application, Lotryl 20MA08 from Arkema is selected.

[0063] In the embodiment of the present application, dicumyl peroxide is sourced from Shanghai Aladdin Reagent Co., Ltd.

[0064] In the scheme of the present application, the graft copolymer of fluoroelastomer-g-EMA is generated in situ by reaction as a compatibilizer to improve the compatibility between fluoroelastomers with different molecular weights. The ethylene-methyl acrylate copolymer and dicumyl peroxide are uniformly mixed with fluoroelastomer raw rubber, and the free radical reaction of EMA is initiated in situ in the fluoroelastomer system in the subsequent vulcanization reaction to generate the graft copolymer of fluoroelastomer-g-EMA as a compatibilizer to improve the compatibility of fluoroelastomers with different molecular weights, which can improve the mechanical properties of the rubber roll, especially the wear resistance and tear resistance. EMA is grafted with fluoroelastomer through free radical reaction to form a graft copolymer with the characteristics of both fluoroelastomer and EMA. The EMA segment can intertwine with the low molecular weight fluoroelastomer segment, while the fluoroelastomer segment can intertwine with the high molecular weight fluoroelastomer segment, thereby playing a bridging role, reducing the interfacial tension between fluoroelastomers with different molecular weights, and improving their compatibility. The compatibilizer generated in situ can be more uniformly dispersed in the fluoroelastomer matrix, thereby better playing a role.

[0065] In addition, although the tetrafluoroethylene-propylene copolymer (FEP) has good wear resistance and lubricity, it has poor compatibility with the two fluoroelastomer raw rubbers and is easy to precipitate on the surface of the rubber roll, affecting the gold stamping quality. The precipitated FEP forms an isolation layer, reducing the contact area between the rubber roll and the printing substrate, resulting in uneven gold stamping. Moreover, the precipitation of FEP increases the surface roughness of the rubber roll, affecting the gold stamping effect.

[0066] Therefore, the high-temperature-resistant composite material for gold stamping rubber roll according to the present application further comprises the following raw materials according to weight fractions:

[0067] The fluorocarbon surfactant is 0.5-1.5 parts by weight.

[0068] The fluorocarbon surfactant is used as a compatibilizer. The fluorocarbon surfactant (such as FC-4430) is added to the fluoroelastomer and mixed uniformly. The fluorocarbon surfactant has a fluorophilic end and an oleophilic end, which can simultaneously interact with fluoroelastomer and FEP, improving the dispersibility of FEP in the fluoroelastomer matrix and the compatibility between the two. After adding the fluorocarbon surfactant, the amount of FEP precipitated can be significantly reduced, the smoothness of the rubber roll surface can be improved, and the gold stamping effect can be improved.

[0069] In the present application, a preparation method of the above-mentioned high-temperature-resistant composite material for gold stamping rubber roll is also provided, comprising the following steps:

[0070] Step 1: raw rubber pretreatment:

[0071] The high molecular weight fluoroelastomer raw rubber and the low molecular weight fluoroelastomer raw rubber are uniformly mixed to obtain a fluoroelastomer raw rubber mixture.

[0072] Further, the obtained fluororubber compound can be plasticized in an internal mixer. Specifically, the temperature can be controlled at 50-60°C, and the time can be 8-12 minutes, so as to ensure that the two compounds are mixed uniformly, and the viscosity of the fluororubber compound is reduced and the processability is improved.

[0073] When the raw material of the gilding roller resistant to high temperature comprises ethylene-methyl acrylate copolymer and dicumyl peroxide, the following steps are further included before adding boron nitride nanosheets and tetrafluoroethylene-propylene copolymer:

[0074] The ethylene-methyl acrylate copolymer (EMA), dicumyl peroxide (DCP) and fluororubber compound are plasticized in an internal mixer.

[0075] In this plasticizing process, the temperature can be controlled at 50-60°C, and the time can be 10-15 minutes, so as to ensure that the two compounds are mixed uniformly.

[0076] Step 2: filler dispersion:

[0077] The fluororubber compound is transferred to an open mill, and the boron nitride nanosheets and tetrafluoroethylene-propylene copolymer are added in batches and mixed uniformly.

[0078] In this step 2, the boron nitride nanosheets and tetrafluoroethylene-propylene copolymer are preferably added in small batches, and each time a small amount of filler is added, the roller gap is adjusted to 0.5-0.8 mm, and fully mixed to ensure that the boron nitride nanosheets and tetrafluoroethylene-propylene copolymer are uniformly dispersed. Multiple thin passes can increase the contact area of the rubber and the roller, and improve the dispersion efficiency of the filler. This filler dispersion step needs to last at least 15-20 minutes.

[0079] When the raw material of the gilding roller resistant to high temperature comprises fluorocarbon surfactant (FC-4430), the fluorocarbon surfactant is added at the same time when the boron nitride nanosheets and tetrafluoroethylene-propylene copolymer are added, so as to further improve the dispersibility of the filler.

[0080] Step 3: internal mixing:

[0081] The rubber obtained in step 2 is transferred to an internal mixer, and magnesium oxide, diamine curing agent and accelerator are added and mixed uniformly.

[0082] In this step, the speed of the internal mixer can be set to 50-70 rpm, the mixing temperature is controlled at 65-75°C, and the total mixing time is 15-25 minutes. The state of the rubber is observed to avoid scorching.

[0083] Step 4: open mill sheeting:

[0084] The rubber compound obtained in step 3 is transferred to the open mill, the roll gap is adjusted to 2 mm, and open mixing is performed for 5-10 minutes, so as to further improve the uniformity of the rubber compound and release the heat generated during mixing;

[0085] The roll temperature is adjusted to 25-35°C, and mixing is performed for 3-5 minutes, so as to effectively reduce the temperature of the rubber compound and prevent scorching;

[0086] The roll gap is adjusted to 2-10 mm, and sheeting is performed, with the thickness of the rubber sheet being controlled to 2-10 mm.

[0087] In this step, open mixing is performed on the open mill in two times, so as to improve the quality of the product.

[0088] Step 5: mold vulcanization

[0089] The sheeted rubber sheet is cut into a suitable size and placed in a mold preheated to 160-170°C, and vulcanization is performed on a flat vulcanizing machine.

[0090] In this step, a stepwise vulcanization process is adopted, specifically: 160-170°C for 20-30 minutes, and then the temperature is raised to 185-195°C, and vulcanization is performed for 2.5-3.5 hours. During the vulcanization process, it is necessary to ensure that the mold is tightly attached to the rubber compound to avoid the occurrence of bubbles.

[0091] Step 5: post-processing

[0092] The gilded rubber roller after vulcanization is taken out of the mold with a high-temperature-resistant composite material for demolding treatment;

[0093] The flash and burrs on the surface of the high-temperature-resistant composite material for gilded rubber roller are removed using an edge trimming knife;

[0094] The surface of the high-temperature-resistant composite material for gilded rubber roller is polished using sandpaper to improve the surface finish.

[0095] The present application is further illustrated by specific examples. Example 1

[0096] The formula of the product is as follows:

[0097] High molecular weight fluororubber raw rubber: 50 parts (Viton E60C, DuPont);

[0098] Low molecular weight fluororubber raw rubber: 50 parts (Viton E45, DuPont);

[0099] Boron nitride nanosheet: 15 parts by weight (BNNS-50, Xi'an Ruiyi);

[0100] Tetrafluoroethylene-propylene copolymer: 7.5 parts by weight (FE2701, Shanghai San'ai Fu);

[0101] Magnesium oxide: 3.5 parts by weight (light magnesium oxide, National Pharmaceutical Group Chemical Reagent Co., Ltd.);

[0102] Diamine curing agent: 2 parts by weight (2-aminoethyl aminocaproic acid, Hubei Qianmo);

[0103] Accelerator: 1 part by weight (Viton Curative VC-50, DuPont).

[0104] The product preparation method is as follows:

[0105] 1. Mix the high molecular weight fluororubber and low molecular weight fluororubber uniformly. Plasticize the mixed fluororubber mixture in an internal mixer, control the temperature at 55°C, and the time for 10 minutes, so that it is fully mixed uniformly.

[0106] 2. Transfer the plasticized fluororubber mixture to an open mill.

[0107] 3. Add boron nitride nanosheets and tetrafluoroethylene-propylene copolymer in batches, add a small amount of filler each time, adjust the roll gap to 0.8 mm, and fully mix to ensure uniform dispersion of the filler. This step mixes for 15 minutes.

[0108] 4. Add the mixed rubber, magnesium oxide, diamine curing agent, and accelerator to the internal mixer.

[0109] 5. Set the internal mixer speed to 60 rpm, and the mixing temperature to 70°C. The total mixing time is 15 minutes.

[0110] 6. Transfer the mixed rubber to an open mill, adjust the roll gap to 2 mm, and perform open mixing for 5 minutes. Adjust the roll temperature to 30°C and mix for 3 minutes.

[0111] 7. Adjust the roll gap to 3 mm and perform sheet pressing, controlling the rubber sheet thickness to 3 mm.

[0112] 8. Cut the pressed rubber into the appropriate size and place it in a mold preheated to 165°C.

[0113] 9. Perform vulcanization on a flat plate vulcanizer. Use a stepwise vulcanization process, specifically: 165°C for 25 minutes, then increase the temperature to 190°C and vulcanize for 3 hours.

[0114] 10. Remove the vulcanized product from the mold and perform demolding.

[0115] 11. Use an edge trimmer to remove the flash and burrs on the surface of the product.

[0116] 12. Use sandpaper to polish the surface of the product to improve the surface finish.

[0117] Performance test of the product:

[0118] 1. Abrasion resistance test: Akron Abrasion Tester was used according to GB / T 1689-2014 standard. Test condition: load of 5N, rotation speed of 75r / min, test time of 30min. Test result: abrasion amount of 0.18cm 3 .

[0119] 2. Shore hardness test: Shore A hardness tester was used according to GB / T 531.1-2008 standard. Test result: Shore A hardness of 95.

[0120] 3. Tensile strength test: universal mechanical testing machine was used according to GB / T 528-2009 standard. Test condition: tensile rate of 500mm / min. Test result: tensile strength of 18MPa.

[0121] 4. Elongation at break test: universal mechanical testing machine was used according to GB / T 528-2009 standard. Test condition: tensile rate of 500mm / min. Test result: elongation at break of 250%.

[0122] 5. Compression set: test was performed according to GB / T 7759.1-2015 standard, under the condition of 150℃ for 24 hours, and the compression set rate was measured. Test result: compression set rate of 18%.

[0123] 6. Heat aging test: the sample was placed in an oven at 200℃ for 72 hours, and then the changes of Shore hardness, tensile strength and elongation at break were tested. Test result: change of Shore hardness of +3, change of tensile strength of -10%, change of elongation at break of -15%. Example 2

[0124] The formula of the product is as follows:

[0125] High molecular weight fluororubber raw rubber: 60 parts (Viton E60C, DuPont Company);

[0126] Low molecular weight fluororubber raw rubber: 40 parts (Viton E45, DuPont Company);

[0127] Boron nitride nanosheet: 10 parts by weight (BNNS-50, Xi'an Ruiyi);

[0128] Tetrafluoroethylene-propylene copolymer: 5 parts by weight (FE2701, Shanghai Sanai Fu);

[0129] Magnesium oxide: 2 parts by weight (light magnesium oxide, Sinoreagent Chemical Co., Ltd.);

[0130] Diamine curing agent: 1.5 parts by weight (2-aminoethyl aminocaproic acid, Hubei Qianmo);

[0131] Accelerator: 0.5 parts by weight (Viton Curative VC-50, DuPont).

[0132] The product was prepared in the same way as in Example 1.

[0133] The product was tested for performance:

[0134] 1. Abrasion resistance test: Akron abrasion tester was used, and the test was carried out according to GB / T 1689-2014 standard. Test conditions: load 5N, rotation speed 75r / min, test time 30min. Test result: abrasion amount 0.22cm 3 .

[0135] 2. Shore hardness test: Shore A hardness tester was used, and the test was carried out according to GB / T 531.1-2008 standard. Test result: Shore A hardness 98.

[0136] 3. Tensile strength test: universal mechanical testing machine was used, and the test was carried out according to GB / T 528-2009 standard. Test conditions: tensile rate 500mm / min. Test result: tensile strength 20MPa.

[0137] 4. Elongation at break test: universal mechanical testing machine was used, and the test was carried out according to GB / T 528-2009 standard. Test conditions: tensile rate 500mm / min. Test result: elongation at break 220%.

[0138] 5. Compression set: the test was carried out according to GB / T 7759.1-2015 standard, and the compression set rate was measured after compression for 24 hours at 150℃. Test result: compression set rate 20%.

[0139] 5. Heat aging test: the sample was placed in an oven at 200℃ for 72 hours, and then the changes in Shore hardness, tensile strength and elongation at break were tested. Test result: Shore hardness change +2, tensile strength change -8%, elongation at break change -15%. Example 3

[0140] The product formula is as follows:

[0141] High molecular weight fluororubber gum: 50 parts by weight (Viton E60C, DuPont);

[0142] Low molecular weight fluoroelastomer raw rubber: 50 parts by weight (Viton E45, DuPont);

[0143] Boron nitride nanosheet: 15 parts by weight (BNNS-50, Xi'an Ruihi);

[0144] Tetrafluoroethylene-propylene copolymer: 7.5 parts by weight (FE2701, Shanghai Sanai Fu);

[0145] Magnesium oxide: 3.5 parts by weight (light magnesium oxide, National Pharmaceutical Group Chemical Reagent Co., Ltd.);

[0146] Fluorocarbon surfactant: 1 part by weight (FC-4430, 3M Company);

[0147] EMA: 3 parts by weight (Lotryl 20MA08, Arkema);

[0148] DCP: 0.03 parts by weight (dicumyl peroxide, analytical pure, Shanghai Aladdin Reagent Co., Ltd.);

[0149] Diamine curing agent: 2 parts by weight (2-aminoethyl carbamic acid, Hubei Qianmo);

[0150] Accelerator: 1 part by weight (Viton Curative VC-50, DuPont).

[0151] The preparation method of the product is as follows:

[0152] 1. Mix the high molecular weight fluoroelastomer raw rubber and the low molecular weight fluoroelastomer raw rubber uniformly. Mix the mixed fluoroelastomer raw rubber mixture in the internal mixer, control the temperature at 55℃, and the time for 10 minutes, so as to fully mix uniformly.

[0153] 2. Weigh the ethylene-methyl acrylate copolymer (EMA) and dicumyl peroxide (DCP) according to the formula proportion.

[0154] 3. Add EMA and DCP, and mix with the fluoroelastomer raw rubber mixture in the internal mixer, control the temperature at 60℃, and the plasticizing time for 12 minutes, so as to fully mix uniformly.

[0155] 4. Transfer the plasticized fluoroelastomer raw rubber mixture to the open mill.

[0156] 5. Add boron nitride nanosheet, tetrafluoroethylene-propylene copolymer and fluorocarbon surfactant (FC-4430) in batches. Add a small amount of filler each time, adjust the roll gap to 0.8mm, and mix thoroughly to ensure uniform dispersion of the filler. This step mixes for 15 minutes.

[0157] 6. Add the mixed rubber, magnesium oxide, diamine curing agent and accelerator to the internal mixer.

[0158] 7. Set the speed of the internal mixer to 60 rpm, and control the mixing temperature at 70°C. The total mixing time is 15 minutes.

[0159] 8. Transfer the mixed rubber compound to the open mill, and adjust the roll gap to 2 mm. Perform open mixing for 5 minutes. Adjust the roll temperature to 30°C, and mix for 3 minutes.

[0160] 9. Adjust the roll gap to 3 mm, and perform sheet pressing. Control the thickness of the rubber sheet to be 3 mm.

[0161] 10. Cut the pressed rubber compound into appropriate sizes, and place them in the mold preheated to 165°C.

[0162] 11. Perform vulcanization on the flat vulcanization machine. Use a stepwise vulcanization process, specifically: 165°C for 25 minutes, then increase the temperature to 190°C, and vulcanize for 3 hours.

[0163] 12. Remove the vulcanized product from the mold, and perform demolding.

[0164] 13. Use a trimming knife to remove the flash and burrs on the surface of the product.

[0165] 14. Use sandpaper to polish the surface of the product, to improve the surface finish.

[0166] Test the performance of the product:

[0167] 1. Abrasion resistance test: use an Akron abrasion tester, and test according to the GB / T 1689-2014 standard. Test conditions: load is 5N, rotation speed is 75r / min, and test time is 30 minutes. Test result: abrasion amount is 0.15cm 3 .

[0168] 2. Shore hardness test: use a Shore A hardness tester, and test according to the GB / T 531.1-2008 standard. Test result: Shore A hardness is 96.

[0169] 3. Tensile strength test: use a universal mechanical testing machine, and test according to the GB / T 528-2009 standard. Test conditions: tensile rate is 500mm / min. Test result: tensile strength is 20MPa.

[0170] 4. Elongation at break test: use a universal mechanical testing machine, and test according to the GB / T 528-2009 standard. Test conditions: tensile rate is 500mm / min. Test result: elongation at break is 280%.

[0171] 5. Compression set: The compression set was tested according to GB / T 7759.1-2015 standard, at 150℃ for 24 hours, and the compression set rate was measured. The test result: the compression set rate was 16%.

[0172] 6. Heat aging test: The sample was placed in an oven at 200℃ for 72 hours, and then the change of Shore hardness, tensile strength and elongation at break was tested. The test result: the change of Shore hardness was +2, the change of tensile strength was -7%, and the change of elongation at break was -10%. Example 4

[0173] The formula of the product is as follows:

[0174] High molecular weight fluororubber raw rubber: 55 parts by weight (Viton E60C, DuPont);

[0175] Low molecular weight fluororubber raw rubber: 55 parts by weight (Viton E45, DuPont);

[0176] Boron nitride nanosheet: 12 parts by weight (BNNS-50, Beijing Dike Nanotechnology Co., Ltd.);

[0177] Tetrafluoroethylene-propylene copolymer: 6 parts by weight (FE2701, Shanghai Sanai Fu);

[0178] Magnesium oxide: 4 parts by weight (light magnesium oxide, National Pharmaceutical Group Chemical Reagent Co., Ltd.);

[0179] Fluorocarbon surfactant: 0.8 parts by weight (FC-4430, 3M Company);

[0180] EMA: 2.5 parts by weight (Lotryl 20MA08, Arkema);

[0181] DCP: 0.038 parts by weight (DCP, analytical pure, Shanghai Aladdin Reagent Co., Ltd.);

[0182] Diamine curing agent: 2.2 parts by weight (2-aminoethyl aminocaproic acid, Hubei Qianmo);

[0183] Accelerator: 0.8 parts by weight (Viton Curative VC-50, DuPont).

[0184] The preparation method of the product is the same as that of Example 3.

[0185] The performance of the product was tested:

[0186] 1. Abrasion resistance test: The Akron Abrasion Tester was used to test according to the GB / T 1689-2014 standard. Test conditions: load of 5N, rotation speed of 75r / min, test time of 30min. Test results: abrasion amount of 0.12cm 3 .

[0187] 2. Shore hardness test: The Shore A hardness tester was used to test according to the GB / T 531.1-2008 standard. Test results: Shore A hardness of 95.

[0188] 3. Tensile strength test: The universal mechanical testing machine was used to test according to the GB / T 528-2009 standard. Test conditions: tensile rate of 500mm / min. Test results: tensile strength of 22MPa.

[0189] 4. Elongation at break test: The universal mechanical testing machine was used to test according to the GB / T 528-2009 standard. Test conditions: tensile rate of 500mm / min. Test results: elongation at break of 290%.

[0190] 5. Compression set: The test was carried out according to the GB / T 7759.1-2015 standard, under the condition of 150℃ for 24 hours, and the compression set rate was measured. Test results: compression set rate of 15%.

[0191] 6. Heat aging test: The sample was placed in an oven at 200℃ for 72 hours, and then the changes in Shore hardness, tensile strength and elongation at break were tested. Test results: change in Shore hardness of +2, change in tensile strength of -7%, change in elongation at break of -11%.

[0192] Control group:

[0193] A brand of gold stamping cigarette package gold stamping, laser film anti-counterfeiting process fluororubber roller on the market was selected as the control group, and the main components of the roller were fluororubber, carbon black and a small amount of inorganic filler.

[0194] Performance tests were carried out on the control group products, and the test methods and test standards were the same as the experimental case, and the following performance data results were obtained:

[0195] 1. Abrasion resistance test: abrasion amount of 0.25cm 3 .

[0196] 2. Shore hardness test: Shore A hardness of 78.

[0197] 3. Tensile strength test: tensile strength of 16MPa.

[0198] 4. Elongation at break test: elongation at break of 200%.

[0199] 5. Heat aging test: Shore hardness change +5, tensile strength change -15%, elongation at break change -20%.

[0200] In summary, the gilding glue roller resistant high temperature composite material provided by the application significantly improves the wear resistance of the product by adding boron nitride nanosheets and tetrafluoroethylene-propylene copolymer, and reduces the wear amount; by adjusting the proportion of fluorine rubber with different molecular weights, the elastic recovery performance of the product is optimized, and the compression permanent deformation is reduced, the compatibility agent is generated in situ, and the mechanical properties of the product are further improved, especially the tensile strength and elongation at break; excellent heat aging resistance, still can keep good mechanical properties under high temperature conditions. Compared with the same kind of products on the market, the gilding glue roller resistant high temperature composite material provided by the application has obvious advantages in wear resistance, heat aging resistance and other aspects, has excellent high temperature resistance and aging resistance, has good application prospect, can work stably in high temperature environment such as gilding cigarette package gilding, laser film anti-counterfeiting process, and prolongs the service life.

[0201] It should be understood that the application of the application is not limited to the above examples, and those skilled in the art can improve or change according to the above description, and all these improvements and changes shall belong to the protection scope of the application.

Claims

1. A high-temperature resistant composite material for hot stamping rollers, characterized in that, According to the weight parts, including the following raw materials: High molecular weight fluorine rubber raw rubber: 40-60 parts; Low molecular weight fluorine rubber raw rubber: 60-40 parts; Boron nitride nanosheet: 10-20 parts; Tetrafluoroethylene-propylene copolymer: 5-10 parts; Magnesium oxide: 2-5 parts; Diamine curing agent: 1.5-2.5 parts; Accelerator: 0.5-1.5 parts; The high molecular weight fluorine rubber raw rubber is Viton E60C, and the low molecular weight fluorine rubber raw rubber is Viton E45.

2. The high temperature resistant composite material for gilding roller according to claim 1, characterized in that, The gold stamping roller is made of high-temperature-resistant composite material, and according to the weight parts, it further includes the following raw materials: Ethylene-methyl acrylate copolymer: 1%-5% of the total mass of high molecular weight fluorine rubber raw rubber and low molecular weight fluorine rubber raw rubber; Dicumyl peroxide: 0.5%-2% of the mass of ethylene-methyl acrylate copolymer.

3. The high temperature resistant composite material for gilding roller according to claim 1, characterized in that, The gold stamping roller is made of high-temperature-resistant composite material, and according to the weight parts, it further includes the following raw materials: Fluorocarbon surfactant: 0.5-1.5 parts by weight.

4. The high temperature resistant composite material for gilding roller according to claim 1, characterized in that, The mass ratio of the high molecular weight fluorine rubber raw rubber to the low molecular weight fluorine rubber raw rubber is 1:

1.

5. The high temperature resistant composite material for gilding roller according to claim 1, characterized in that, The accelerator is Viton Curative VC-50.

6. The high temperature resistant composite material for gilding roller according to claim 1, characterized in that, The particle size of the boron nitride nanosheet ranges from 30-100 nm.

7. The high temperature resistant composite material for gilding roller according to claim 1, characterized in that, The magnesium oxide is light magnesium oxide.

8. The high temperature resistant composite material for gilding roller according to claim 1, characterized in that, The diamine curing agent is 2-aminoethyl aminocarbamate or di(orthoamino)phenyl disulfide.

9. A method of producing a high-temperature resistant composite material for a gilding roller according to any one of claims 1 to 8, characterized by, Including the following steps: Mix the high molecular weight fluorine rubber raw rubber and the low molecular weight fluorine rubber raw rubber uniformly to obtain a fluorine rubber raw rubber mixture; Add the boron nitride nanosheet and the tetrafluoroethylene-propylene copolymer to the fluorine rubber raw rubber mixture in batches, mix uniformly, and then add the magnesium oxide, the diamine curing agent, and the accelerator, mix uniformly to obtain a mixed compound; Perform tabletting operation on the mixed compound, and control the thickness of the rubber tablet to be 2-10 mm; Vulcanize the rubber tablet: vulcanize at 160-170°C for 20-30 minutes, then increase the temperature to 185-195°C, and vulcanize for 2.5-3.5 hours.

10. The method of claim 9, wherein the gilding roller is a gilding roller for a gilding machine. When the raw materials of the high-temperature-resistant composite material for the gold stamping roller further include ethylene-methyl acrylate copolymer and dicumyl peroxide, the following steps are further included before adding the boron nitride nanosheet and the tetrafluoroethylene-propylene copolymer: Mix the ethylene-methyl acrylate copolymer, the dicumyl peroxide, and the fluorine rubber raw rubber mixture uniformly; When the raw materials of the high-temperature-resistant composite material for the gold stamping roller further include fluorocarbon surfactant, add the fluorocarbon surfactant simultaneously with the boron nitride nanosheet and the tetrafluoroethylene-propylene copolymer; Before performing the tabletting operation on the mixed compound, the following steps are further included: Open-mix the mixed compound for 5-10 minutes, then adjust the roller temperature to 25-35°C, and mix for 3-5 minutes.