High-density silicone rubber suitable for smart wear and preparation process thereof

Abstract

The application relates to the technical field of high polymer materials, and particularly discloses a high-density silicone rubber suitable for intelligent wearing and a preparation process thereof. The high-density silicone rubber suitable for intelligent wearing comprises the following components in mass fractions: 40-60 parts of silicone rubber; 40-48 parts of modified inorganic filler; 0.3-1.5 parts of a coupling agent; 0.1-5 parts of inorganic pigment; 1.6-2.3 parts of a vulcanizing agent; the modified inorganic filler is obtained by modifying a composite inorganic filler with a modifying liquid; the composite inorganic filler is a composite of titanium dioxide, zinc oxide, boron nitride and calcium carbonate whisker; and the modifying liquid is a composite of a solvent, octadecyl trimethyl ammonium chloride, cyclohexene oxide and linoleic acid. The application has the advantage that the high-density silicone rubber can better keep the color from changing.

Description

Technical Field

[0001] This invention relates to the field of polymer materials, and in particular to a high-density silicone rubber formulation suitable for smart wearables and its preparation process. Background Technology

[0002] With the increasing popularity of wearable devices, high-density rubber materials are needed to enhance the texture of these devices and achieve a luxurious feel. Currently, fluororubber is commonly used for high-density rubber. However, perfluorohexanoic acid (PFHxA), a fluorinated organic compound, is a perfluorinated and polyfluoroalkyl substance. It is not environmentally friendly, cannot be recycled, and has non-degradable and bioaccumulative toxicity, posing risks to human health and the environment.

[0003] Silicone rubber is highly biocompatible, non-toxic, and pollution-free, making it the most commonly used rubber material for wearable devices. However, silicone rubber has a low density, which makes it difficult to meet the high-density rubber requirements of wearable devices. To increase the density of silicone rubber, a large amount of inorganic filler needs to be added. However, ordinary inorganic fillers have poor resistance to chemicals such as sweat and oleic acid. After wearing for a long time, the color of the product can be easily affected by sweat. Therefore, there is still room for improvement. Summary of the Invention

[0004] In order to better maintain the color of high-density silicone rubber and prevent it from changing, this application provides a high-density silicone rubber suitable for smart wearables and its preparation process.

[0005] In a first aspect, this application provides a high-density silicone rubber suitable for smart wearables, employing the following technical solution: A high-density silicone rubber suitable for smart wearables, comprising the following components in parts by weight:

[0006] 40-60 parts of silicone rubber;

[0007] 40-48 parts of modified inorganic filler;

[0008] 0.3-1.5 parts of coupling agent;

[0009] Inorganic pigments: 0.1-5 parts;

[0010] 1.6-2.3 parts of vulcanizing agent;

[0011] The modified inorganic filler is obtained by modifying a composite inorganic filler with a modifying liquid;

[0012] The composite inorganic filler is a mixture of titanium dioxide, zinc oxide, boron nitride, and calcium carbonate whiskers;

[0013] The modified liquid is a compound of solvent, octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid.

[0014] By adopting the above technical solution, a modified inorganic filler, obtained by modifying a composite inorganic filler composed of titanium dioxide, zinc oxide, boron nitride, and calcium carbonate whiskers with a modifying liquid composed of octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid, is added to silicone rubber. This significantly increases the density of the silicone rubber, giving it a better texture. Furthermore, it prevents discoloration of the silicone rubber under the long-term effects of sweat and oleic acid, maintaining its vibrant color and resulting in stable quality smart wearable devices.

[0015] Moreover, modified inorganic fillers can significantly improve the strength of silicone rubber, making smart wearable devices made of high-density silicone rubber more durable and less prone to damage.

[0016] Preferably, the mass ratio of titanium dioxide, zinc oxide, boron nitride, and calcium carbonate whiskers in the inorganic filler is 25-27:12-14:16-18:7-9.

[0017] By adopting the above technical solution and specifically selecting the mass ratio of titanium dioxide, zinc oxide, boron nitride, and calcium carbonate whiskers, the combination of titanium dioxide, zinc oxide, boron nitride, and calcium carbonate whiskers in a specific ratio, under the modification effect of the modifying liquid, can better maintain the color stability of high-density silicone rubber and significantly improve the strength of high-density silicone rubber.

[0018] Preferably, in the modified liquid, the mass ratio of solvent, octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid is 100:13-15:11-13:17-19.

[0019] By adopting the above technical solution and by specifically selecting the mass ratio of solvent, octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid, the modifying substances are combined in a specific ratio, resulting in a better modification effect of the modified liquid on the composite inorganic filler. This makes the modified inorganic filler better at maintaining the color stability of high-density silicone rubber and improving the strength of high-density silicone rubber.

[0020] Preferably, the solvent is an ethanol solution.

[0021] By adopting the above technical solution and specifically selecting the ethanol solution, the synergistic effect of the components in the modified solution is improved, resulting in a better modification effect.

[0022] Preferably, the modified inorganic filler is prepared by the following method:

[0023] Step 1): Mix the solvent, octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid evenly to obtain the modified solution;

[0024] Step 2) Mix titanium dioxide, zinc oxide, boron nitride and calcium carbonate whiskers evenly to obtain a composite inorganic filler;

[0025] Step 3): Add the composite inorganic filler to the modification liquid, stir for 4-6 hours, filter out the composite inorganic filler, dry it, and obtain the modified inorganic filler.

[0026] By adopting the above technical solution, the modified inorganic filler can significantly modify silicone rubber, increase the density of silicone rubber, and the color of high-density silicone rubber is not easily changed. Moreover, the strength of silicone rubber can be significantly improved.

[0027] Preferably, in step 3), the composite inorganic filler is added to the modified liquid, kept at a constant temperature of 60-70℃, and stirred for 4-6 hours.

[0028] By adopting the above technical solution and stirring at 60-70℃ for 4-6 hours, the modification is more complete, the modified inorganic filler has higher stability, the high-density silicone rubber is less prone to discoloration, and the high-density silicone rubber has higher strength.

[0029] Preferably, the coupling agent is a silane coupling agent.

[0030] By adopting the above technical solution and specifically selecting silane coupling agents, the compatibility between modified inorganic fillers and silicone rubber is high, and the effect of modified silicone rubber is more significant.

[0031] Secondly, this application provides a method for preparing high-density silicone rubber suitable for smart wearables, employing the following technical solution:

[0032] A method for preparing the above-mentioned high-density silicone rubber suitable for smart wearables includes the following steps:

[0033] Step 01): Mix the modified inorganic filler, inorganic pigment, and coupling agent at 80-100℃ to obtain a premix.

[0034] Step 02): Mix the premix and silicone rubber evenly using a rubber mixing equipment to obtain masterbatch.

[0035] Step 03): Mix the masterbatch and vulcanizing agent evenly using a rubber mixing equipment to obtain the final rubber compound.

[0036] Step 04): Place the final compound in a mold and heat to cure, thus obtaining a high-density silicone rubber suitable for smart wearables.

[0037] By adopting the above technical solution, the high-density silicone rubber produced has a high density, which can exhibit a good texture and well meet the needs of smart wearable devices. In addition, the high-density silicone rubber is not easy to discolor and has high strength, making the smart wearable devices made from it more durable and having high economic value.

[0038] In summary, this application has the following beneficial effects:

[0039] 1. This application utilizes a modified inorganic filler—a composite inorganic filler made from titanium dioxide, zinc oxide, boron nitride, and calcium carbonate whiskers—which is then modified with a modifying liquid made from octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid. Adding this modified inorganic filler to silicone rubber significantly increases its density, resulting in high-density silicone rubber with a superior texture. Furthermore, it prevents discoloration under prolonged exposure to sweat and oleic acid, maintaining the silicone rubber's vibrant color and ensuring stable quality in the resulting smart wearable devices. Moreover, the modified inorganic filler significantly improves the strength of the silicone rubber, making high-density silicone rubber smart wearable devices more durable and less prone to breakage.

[0040] 2. In this application, the preferred method is to specifically select the mass ratio of titanium dioxide, zinc oxide, boron nitride, and calcium carbonate whiskers so that when titanium dioxide, zinc oxide, boron nitride, and calcium carbonate whiskers are mixed in a specific ratio, under the modification effect of the modifying liquid, the color stability of high-density silicone rubber can be better maintained, and the effect of improving the strength of high-density silicone rubber can be more significant.

[0041] 3. In this application, it is preferred to select the specific mass ratio of solvent, octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid so that each modifying substance is combined in a specific ratio. This results in a better modification effect of the modified liquid on the composite inorganic filler, and a better effect of the modified inorganic filler in maintaining the color stability of high-density silicone rubber and improving the strength of high-density silicone rubber. Detailed Implementation

[0042] The present application will be further described in detail below with reference to the embodiments.

[0043] Example 1

[0044] A high-density silicone rubber suitable for smart wearables is made from the following components.

[0045] Silicone rubber, modified inorganic fillers, coupling agents, inorganic pigments, and vulcanizing agents.

[0046] The silicone rubber was purchased from Dow Chemical, model number: RBB-2003.

[0047] The coupling agent was purchased from Shandong Qiyun Chemical Technology Co., Ltd., specifically silane coupling agent KH550.

[0048] The inorganic pigment is Pigment Red 101, purchased from BASF, model number: BASF Sicotrans red L2915D.

[0049] The vulcanizing agent is vulcanizing agent C-8, which was purchased from Dongguan Kexiwei Electronic Materials Co., Ltd.

[0050] Modified inorganic fillers are obtained by modifying composite inorganic fillers with a modifying liquid.

[0051] The composite inorganic filler is a blend of titanium dioxide, zinc oxide, boron nitride, and calcium carbonate whiskers.

[0052] Titanium dioxide was purchased from Langfang Qicai Pigment Co., Ltd.

[0053] Zinc oxide was purchased from Zhengzhou Yiteng Chemical Products Co., Ltd.

[0054] Boron nitride was purchased from Jinan Qiangxin Chemical Co., Ltd.

[0055] The calcium carbonate whiskers were purchased from Hubei Xinyuhong Biomedical Technology Co., Ltd.

[0056] The modified liquid is a compound of solvent, octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid.

[0057] The solvent is an ethanol solution with a concentration of 75%, purchased from Shandong Lanxing New Materials Co., Ltd.

[0058] Octadecyltrimethylammonium chloride was purchased from Hubei Zhongnuo Yaxing Biotechnology Co., Ltd.

[0059] Cyclohexene oxide was purchased from Hunan Jinyu Fine Chemical Co., Ltd.

[0060] Linoleic acid was purchased from Sichuan Huanxu Biotechnology Co., Ltd.

[0061] The preparation method of modified inorganic fillers is as follows:

[0062] Step 1): Add 100 kg of ethanol solution, 13 kg of octadecyltrimethylammonium chloride, 11 kg of cyclohexene oxide and 17 kg of linoleic acid into the reaction vessel, stir at 120 r / min for 10 min, mix evenly to obtain the modified solution.

[0063] Step 2): Add 25 kg of titanium dioxide, 12 kg of zinc oxide, 16 kg of boron nitride, and 7 kg of calcium carbonate whiskers into a stirred tank. Stir at 200 r / min for 15 min until the mixture is homogeneous to obtain the composite inorganic filler.

[0064] Step 3): Add 50 kg of composite inorganic filler and 50 kg of modified liquid into the reactor, keep the temperature at 60℃, stir at 60 r / min for 4 h, filter out the composite inorganic filler, and dry it at 110℃ for 2 h to obtain the modified inorganic filler.

[0065] The preparation method of high-density silicone rubber suitable for smart wearables includes the following steps:

[0066] Step 01): Add 40 kg of modified inorganic filler, 0.1 kg of inorganic pigment, and 0.3 kg of silane coupling agent into a stirred tank, keep the temperature at 80℃, and stir at 60 r / min for 15 min to obtain a premix.

[0067] Step 02): Add 40.4 kg of premix and 40 kg of silicone rubber into an internal mixer, rotate at 60 r / min, keep the temperature at 100℃, and mix for 10 min to obtain masterbatch.

[0068] Step 03): Add 80.4 kg of masterbatch and 1.6 kg of vulcanizing agent to a two-mill, pass through a thin mill 10 times, mix evenly, and obtain the final compound; Step 04): Place the final compound into a mold, vulcanize at 10 MPa and 165°C for 10 min, cool and demold, then vulcanize again at 200°C for 4 h, and cool to room temperature to obtain high-density silicone rubber suitable for smart wearables.

[0069] Example 2

[0070] A high-density silicone rubber suitable for smart wearables is made from the following components.

[0071] Silicone rubber, modified inorganic fillers, coupling agents, inorganic pigments, and vulcanizing agents.

[0072] The silicone rubber was purchased from Dow Chemical, model number: RBB-2003.

[0073] The coupling agent was purchased from Shandong Qiyun Chemical Technology Co., Ltd., specifically silane coupling agent KH550.

[0074] The inorganic pigment is Pigment Red 101, purchased from BASF, model number: BASF Sicotrans red L2915D.

[0075] The vulcanizing agent is vulcanizing agent C-8, which was purchased from Dongguan Kexiwei Electronic Materials Co., Ltd.

[0076] Modified inorganic fillers are obtained by modifying composite inorganic fillers with a modifying liquid.

[0077] The composite inorganic filler is a blend of titanium dioxide, zinc oxide, boron nitride, and calcium carbonate whiskers.

[0078] Titanium dioxide was purchased from Langfang Qicai Pigment Co., Ltd.

[0079] Zinc oxide was purchased from Zhengzhou Yiteng Chemical Products Co., Ltd.

[0080] Boron nitride was purchased from Jinan Qiangxin Chemical Co., Ltd.

[0081] The calcium carbonate whiskers were purchased from Hubei Xinyuhong Biomedical Technology Co., Ltd.

[0082] The modified liquid is a compound of solvent, octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid.

[0083] The solvent is an ethanol solution with a concentration of 75%, purchased from Shandong Lanxing New Materials Co., Ltd.

[0084] Octadecyltrimethylammonium chloride was purchased from Hubei Zhongnuo Yaxing Biotechnology Co., Ltd.

[0085] Cyclohexene oxide was purchased from Hunan Jinyu Fine Chemical Co., Ltd.

[0086] Linoleic acid was purchased from Sichuan Huanxu Biotechnology Co., Ltd.

[0087] The preparation method of modified inorganic fillers is as follows:

[0088] Step 1): Add 100 kg of ethanol solution, 14 kg of octadecyltrimethylammonium chloride, 12 kg of cyclohexene oxide and 18 kg of linoleic acid into the reaction vessel, stir at 120 r / min for 10 min, mix evenly to obtain the modified solution.

[0089] Step 2): Add 26 kg of titanium dioxide, 13 kg of zinc oxide, 17 kg of boron nitride, and 8 kg of calcium carbonate whiskers into a stirred tank. Stir at 200 r / min for 15 min until the mixture is homogeneous to obtain the composite inorganic filler.

[0090] Step 3): Add 50 kg of composite inorganic filler and 50 kg of modified liquid into the reactor, keep the temperature constant at 65℃, rotate at 60 r / min, stir for 5 h, filter out the composite inorganic filler, and dry at 110℃ for 2 h to obtain the modified inorganic filler.

[0091] The preparation method of high-density silicone rubber suitable for smart wearables includes the following steps:

[0092] Step 01): Add 44 kg of modified inorganic filler, 2.5 kg of inorganic pigment and 1 kg of silane coupling agent into a stirred tank, keep the temperature at 90℃, rotate at 60 r / min and stir for 15 min to obtain a premix.

[0093] Step 02): Add 47.5 kg of premix and 50 kg of silicone rubber into an internal mixer, rotate at 60 r / min, maintain a constant temperature of 110℃, and mix for 12 min to obtain masterbatch.

[0094] Step 03): Put 97.5 kg of masterbatch and 1.95 kg of vulcanizing agent into a two-roll mill, pass through it 10 times, mix evenly, and obtain the final rubber compound.

[0095] Step 04): Place the final rubber compound into a mold, vulcanize at 10 MPa and 165°C for 10 minutes, cool and demold, then vulcanize again at 200°C for 4 hours, and cool to room temperature to obtain high-density silicone rubber suitable for smart wearables.

[0096] Example 3

[0097] A high-density silicone rubber suitable for smart wearables is made from the following components.

[0098] Silicone rubber, modified inorganic fillers, coupling agents, inorganic pigments, and vulcanizing agents.

[0099] The silicone rubber was purchased from Dow Chemical, model number: RBB-2003.

[0100] The coupling agent was purchased from Shandong Qiyun Chemical Technology Co., Ltd., specifically silane coupling agent KH550.

[0101] The inorganic pigment is Pigment Red 101, purchased from BASF, model number: BASF Sicotrans red L2915D.

[0102] The vulcanizing agent is vulcanizing agent C-8, which was purchased from Dongguan Kexiwei Electronic Materials Co., Ltd.

[0103] Modified inorganic fillers are obtained by modifying composite inorganic fillers with a modifying liquid.

[0104] The composite inorganic filler is a blend of titanium dioxide, zinc oxide, boron nitride, and calcium carbonate whiskers.

[0105] Titanium dioxide was purchased from Langfang Qicai Pigment Co., Ltd.

[0106] Zinc oxide was purchased from Zhengzhou Yiteng Chemical Products Co., Ltd.

[0107] Boron nitride was purchased from Jinan Qiangxin Chemical Co., Ltd.

[0108] The calcium carbonate whiskers were purchased from Hubei Xinyuhong Biomedical Technology Co., Ltd.

[0109] The modified liquid is a compound of solvent, octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid.

[0110] The solvent is an ethanol solution with a concentration of 75%, purchased from Shandong Lanxing New Materials Co., Ltd.

[0111] Octadecyltrimethylammonium chloride was purchased from Hubei Zhongnuo Yaxing Biotechnology Co., Ltd.

[0112] Cyclohexene oxide was purchased from Hunan Jinyu Fine Chemical Co., Ltd.

[0113] Linoleic acid was purchased from Sichuan Huanxu Biotechnology Co., Ltd.

[0114] The preparation method of modified inorganic fillers is as follows:

[0115] Step 1): Add 100 kg of ethanol solution, 15 kg of octadecyltrimethylammonium chloride, 13 kg of cyclohexene oxide and 19 kg of linoleic acid into the reaction vessel, stir at 120 r / min for 10 min, mix evenly to obtain the modified solution.

[0116] Step 2): Add 27 kg of titanium dioxide, 14 kg of zinc oxide, 18 kg of boron nitride, and 9 kg of calcium carbonate whiskers into a stirring vessel, stir at 200 r / min for 15 min, and mix evenly to obtain a composite inorganic filler.

[0117] Step 3): Add 50 kg of composite inorganic filler and 50 kg of modified liquid into the reactor, keep the temperature at 70℃, rotate at 60 r / min, stir for 6 h, filter out the composite inorganic filler, and dry at 110℃ for 2 h to obtain the modified inorganic filler.

[0118] The preparation method of high-density silicone rubber suitable for smart wearables includes the following steps:

[0119] Step 01): Add 48 kg of modified inorganic filler, 5 kg of inorganic pigment, and 1.5 kg of silane coupling agent into a stirred tank, keep the temperature at 100℃, rotate at 60 r / min, and stir for 15 min to obtain a premix.

[0120] Step 02): Add 54.5 kg of premix and 60 kg of silicone rubber into an internal mixer, rotate at 60 r / min, keep the temperature at 120℃, and mix for 15 min to obtain masterbatch.

[0121] Step 03): Add 114.5 kg of masterbatch and 2.3 kg of vulcanizing agent into the open mill, pass through it 10 times, mix evenly, and obtain the final rubber compound.

[0122] Step 04): Place the final rubber compound into a mold, vulcanize at 10 MPa and 165°C for 10 minutes, cool and demold, then vulcanize again at 200°C for 4 hours, and cool to room temperature to obtain high-density silicone rubber suitable for smart wearables.

[0123] Comparative Example 1

[0124] A high-density silicone rubber suitable for smart wearables, differing from Example 1 only in that:

[0125] In the preparation method of modified inorganic filler, sodium p-toluenesulfonate is used to replace octadecyltrimethylammonium chloride in an equal amount.

[0126] Sodium p-toluenesulfonate was purchased from Shandong Ruifeng New Materials Co., Ltd.

[0127] Comparative Example 2

[0128] A high-density silicone rubber suitable for smart wearables, differing from Example 1 only in that:

[0129] In the preparation method of modified inorganic filler, polyethylene glycol-2000 is used to replace cyclohexene oxide in an equal amount.

[0130] Polyethylene glycol-2000 was purchased from Ba Shifu (Shanghai) Biomedical Technology Co., Ltd.

[0131] Comparative Example 3

[0132] A high-density silicone rubber suitable for smart wearables, differing from Example 1 only in that:

[0133] In the preparation method of modified inorganic fillers, isomeric tridecyl alcohol polyoxyethylene ether is used to replace linoleic acid in an equal amount.

[0134] Isotridecyl alcohol polyoxyethylene ether was purchased from Shandong Tianzeda Chemical Co., Ltd.

[0135] Comparative Example 4

[0136] A high-density silicone rubber suitable for smart wearables, differing from Example 1 only in that:

[0137] In the preparation method of the modified inorganic filler, sodium p-toluenesulfonate is used to replace octadecyltrimethylammonium chloride in an equal amount; polyethylene glycol-2000 is used to replace cyclohexene oxide in an equal amount; and isomeric tridecyl alcohol polyoxyethylene ether is used to replace linoleic acid in an equal amount.

[0138] Sodium p-toluenesulfonate was purchased from Shandong Ruifeng New Materials Co., Ltd.

[0139] Polyethylene glycol-2000 was purchased from Ba Shifu (Shanghai) Biomedical Technology Co., Ltd.

[0140] Isotridecyl alcohol polyoxyethylene ether was purchased from Shandong Tianzeda Chemical Co., Ltd.

[0141] Experiment 1

[0142] Chemical resistance test

[0143] 1. Samples of high-density silicone rubber suitable for smart wearables, as described in the embodiments and comparative examples, were prepared with a length of 5cm, a width of 5cm, and a thickness of 1mm.

[0144] Each example or comparative example consists of a set of 11 samples. One sample is randomly selected from each set as a control sample, and the remaining 10 samples are to be tested.

[0145] The control sample was placed in the air, while the test sample was immersed in a sodium chloride solution at a constant temperature of 60°C for 48 hours. The test sample was then compared with the control sample, and the color of each test sample was observed to see if there was a visible difference from the color of the control sample. The number of test samples whose color was visible to the control sample was recorded as the number of sodium chloride solution samples that changed color.

[0146] Sodium chloride solution: Mix 5g sodium chloride and 95g tap water thoroughly.

[0147] 2. Samples of high-density silicone rubber suitable for smart wearables, as described in the embodiments and comparative examples, were prepared with a length of 5cm, a width of 5cm, and a thickness of 1mm.

[0148] Each example or comparative example consists of a set of 11 samples. One sample is randomly selected from each set as a control sample, and the remaining 10 samples are to be tested.

[0149] The control sample was placed in the air, and the test sample was immersed in oleic acid at a constant temperature of 60°C for 48 hours. The test sample was compared with the control sample, and the color of the test sample was observed to see if there was a visible difference from the color of the control sample. The number of test samples with a visible difference from the color of the control sample was recorded as the number of oleic acid sample color changes.

[0150] Oleic acid was purchased from Shandong Hairui New Materials Co., Ltd., with a purity of 99.9%.

[0151] Experiment 2

[0152] The tensile strength of the test samples made of high-density silicone rubber suitable for smart wearables in each embodiment and comparative example was tested according to GB / T528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber".

[0153] The specimen used was a dumbbell-shaped specimen, type 1.

[0154] In the laboratory, the tensile testing machine has a tensile speed of 500 mm / min, an ambient temperature of 25℃, and a relative humidity of 50%.

[0155] The detailed experimental data for Experiments 1-2 are shown in Table 1.

[0156] Table 1

[0157]

[0158]

[0159] Based on the data comparison of each embodiment and comparative example in Table 1, it can be seen that the chemical resistance of each embodiment is significantly better than that of each comparative example. Each embodiment did not show discoloration after being immersed in sodium chloride solution and oleic acid for a long time at high temperature, proving that the high-density silicone rubber of each embodiment can maintain color stability for a long time when worn on the human body and is not prone to discoloration.

[0160] Meanwhile, the tensile strength of each embodiment is significantly higher than that of each comparative example, proving that the modification of the composite inorganic filler with octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid in each embodiment is more effective. This allows the modified inorganic filler to better stabilize the pigment color, making the high-density silicone rubber less prone to discoloration. At the same time, it can significantly improve the tensile strength of the high-density silicone rubber, making it less prone to breakage and with a longer service life.

[0161] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A high-density silicone rubber suitable for smart wearables, characterized in that: The composition includes the following components in parts by weight: 40-60 parts silicone rubber; 40-48 parts of modified inorganic filler; 0.3-1.5 parts of coupling agent; Inorganic pigments: 0.1-5 parts; 1.6-2.3 parts of vulcanizing agent; The modified inorganic filler is obtained by modifying a composite inorganic filler with a modifying liquid; The composite inorganic filler is a mixture of titanium dioxide, zinc oxide, boron nitride, and calcium carbonate whiskers; The modified liquid is a compound of solvent, octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid; In the inorganic filler, the mass ratio of titanium dioxide, zinc oxide, boron nitride, and calcium carbonate whiskers is 25-27:12-14:16-18:7-9. In the modified liquid, the mass ratio of solvent, octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid is 100:13-15:11-13:17-19. The preparation method of the modified inorganic filler is as follows: Step 1), mix the solvent, octadecyltrimethylammonium chloride, cyclohexene oxide, and linoleic acid evenly to obtain the modified solution; Step 2), mix titanium dioxide, zinc oxide, boron nitride and calcium carbonate whiskers evenly to obtain a composite inorganic filler; Step 3) Add the composite inorganic filler to the modification solution, stir for 4-6 hours, filter out the composite inorganic filler, dry it, and obtain the modified inorganic filler. In step 3), the composite inorganic filler is added to the modified liquid, kept at a constant temperature of 60-70℃, and stirred for 4-6 hours.

2. The high-density silicone rubber suitable for smart wearables according to claim 1, characterized in that: The solvent is an ethanol solution.

3. The high-density silicone rubber suitable for smart wearables according to claim 1, characterized in that: The coupling agent is a silane coupling agent.

4. A method for preparing high-density silicone rubber suitable for smart wearables according to any one of claims 1-3, characterized in that: Includes the following steps: Step 01): Mix the modified inorganic filler, inorganic pigment, and coupling agent at 80-100℃ to obtain a premix. Step 02), the premix and silicone rubber are mixed evenly using a rubber mixing equipment to obtain masterbatch; Step 03) Mix the masterbatch and vulcanizing agent evenly using a rubber mixing equipment to obtain the final rubber compound; Step 04): Place the final compound in a mold and heat to cure, thus obtaining a high-density silicone rubber suitable for smart wearables.

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