Hollow glass nano-microsphere modified organic silicon elastomer and preparation method thereof

Abstract

The invention relates to the field of polymer composite materials, and discloses a hollow glass nano-microsphere modified organic silicon elastomer and a preparation method thereof. The material is prepared from the following components in percentage by mass: 60-90% of vinyl silicone oil, 0.1-10% of hydrogen-containing silicone oil, 1-20% of an MQ silicon resin solution, 1-50 ppm of a catalyst, 0.05-0.3% of an inhibitor, 5-20% of a solvent and 0.1-5% of hollow glass nano-microsphere turbid liquid, the m / q value of MQ silicon resin is 0.5-1.0, and hollow glass nano-microspheres are silicon dioxide hollow submicrospheres. The preparation method comprises the following steps: mixing the raw materials, adding a catalyst, hydrogen-containing silicone oil and an inhibitor into two groups, mixing, defoaming, curing and forming. The material has good flexibility, ductility, air permeability and moisture permeability, high thermal stability and excellent biocompatibility, and is suitable for the fields of artificial skin and the like.

Description

Technical Field

[0001] This invention relates to the field of polymer composite materials, and more specifically to an organosilicon elastomer material for manufacturing artificial skin and its preparation process. Background Art

[0002] Organosilicon elastomers are a class of synthetic polymers with silicon-oxygen bonds as the main chain and organic groups (such as methyl groups) attached to the side chains. They integrate the stability of inorganic materials with the flexibility of organic materials, exhibiting extremely excellent comprehensive properties: maintaining excellent elasticity and resilience over a very wide temperature range of -50℃ to 200℃; possessing outstanding chemical stability, weather resistance, and electrical insulation; and also possessing good biocompatibility, low surface energy, and good permeability to various gases. These properties make them key materials for medical devices, electronics, automotive industry, aerospace, building sealing, and emerging fields such as soft robotics and biomimetic skin. They are typically formed by curing and cross-linking liquid or paste prepolymers, and their properties can be widely controlled by adjusting the molecular structure, cross-linking density, and adding fillers.

[0003] Hollow glass nanospheres are submicron-sized microspheres with a hollow structure, composed of silica. Made of chemically stable inorganic glass, they possess excellent heat resistance, chemical inertness, insulation, and a certain degree of mechanical strength. They are easily dispersed, can be added to product formulations, and can reduce the amount of filler required. In addition to significant weight reduction, their closed hollow structure provides good thermal and sound insulation properties and may affect the dielectric constant or electromagnetic wave characteristics of the material. Therefore, this material is suitable as a modifier added to organosilicon products.

[0004] Existing silicone elastomers suffer from performance issues such as insufficient density, reduced strength and toughness, and low functional integration. Silicone elastomers modified with hollow glass nanospheres hold great potential for application in the field of high-performance silicone artificial skins. Through modification, silicone composite materials with ultra-low density, good flexibility and ductility, high biocompatibility, and good air and moisture permeability can be prepared to meet the requirements of high-end artificial skins. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, the present invention aims to provide a hollow glass nanosphere modified organosilicon elastomer and its preparation method. This material can provide good flexibility, ductility and air and moisture permeability, and is suitable for the field of artificial skin.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] 1. A hollow glass nanosphere modified organosilicon elastomer, composed of the following raw materials in the following mass ratio:

[0008] The composition includes 60-90% vinyl silicone oil, 0.1-10% hydrogen-containing silicone oil, 1-20% MQ silicone resin solution, 1-50 ppm catalyst, 0.05-0.3% inhibitor, and 5-20% solvent, along with 0.1-5% hollow glass nanosphere suspension.

[0009] The MQ silicone resin solution is prepared by mixing MQ silicone resin with a non-toxic and non-irritating solvent, with a mass fraction of 10-50%. The MQ silicone resin is prepared by the hydrolysis and condensation of tetraethyl orthosilicate; the m / q value of the MQ silicone resin is between 0.5 and 1.0. The M / Q value refers to the molar ratio of monofunctional siloxane units (M units) to tetrafunctional siloxane units (Q units).

[0010] The vinyl silicone oil is a methyl silicone oil with terminal or side groups, and a viscosity of 10,000 to 100,000 mPa·s; the vinyl content in the vinyl silicone oil is 0.05 to 0.50%.

[0011] The hydrogen-containing silicone oil has a hydrogen content of 0.02-1%, a molecular weight of 1000-10000, and a viscosity of 5-500 cst.

[0012] The catalyst is one or more of the following: a cassiterite catalyst, a platinum-divinyltetramethyldisiloxane complex, a chloroplatinic acid solution, and a silicone oil dilution solution.

[0013] The inhibitor is one or more of methylbutynol, ethynylcyclohexanol and 1-ethynyl-1-cyclohexanol, methylpentynol and benzotriazole.

[0014] The solvent is one or more of volatile silicone oil or other non-toxic and non-irritating solutions.

[0015] The hollow glass nanospheres are submicron-sized microspheres with a hollow structure made of silica, with a density of 0.1–2 g / cm³. 3 The mass fraction is 15-30%, the particle size distribution is 70-100% (100-1000 nm), and the pH value is 7-10.

[0016] The method for preparing the hollow glass nanosphere suspension is as follows: the hollow glass nanospheres are mixed with a solvent and sonicated for 30 minutes; wherein the mass fraction of the hollow glass nanosphere suspension is 10-30%.

[0017] 2. A method for preparing hollow glass nanosphere-modified organosilicon elastomer, comprising the following steps:

[0018] a. Mix MQ silicone resin solution with vinyl silicone oil and stir thoroughly for 10-20 minutes to obtain the base adhesive;

[0019] b. Mix the base adhesive obtained in step a with the hollow glass nanosphere suspension thoroughly for 10 min to 30 min to obtain a mixed colloid with a certain viscosity;

[0020] Specifically, the mass of the hollow glass nanospheres accounts for 0.1% to 5% of the total mass of the base adhesive;

[0021] c. Divide the mixed colloid obtained in step b into two parts. Add a catalyst to one part and mix evenly to obtain component A; add hydrogen-containing silicone oil and inhibitor to the other part and mix evenly to obtain component B.

[0022] Specifically, the molar ratio of hydrogen to vinyl groups in the added hydrogen-containing silicone oil and vinyl silicone oil is 0.5–3:1, preferably 0.5–1.5:1. The catalyst concentration is preferably 10–30 ppm, and the amount of inhibitor added is 0.1–2% of the total mass of the mixed colloid.

[0023] d. Mix components A and B thoroughly, place in an easily degassed mold, degas, and cure at 30–120℃ for 10–30 minutes. The resulting elastomer will have a thickness of 0.02–1 mm. The elastomer thickness can be adjusted flexibly according to actual application requirements.

[0024] Specifically, easy-to-release molds are made of non-stick materials such as polypropylene, high-density polyethylene, polycarbonate, ABS, polytetrafluoroethylene, or fluorinated release film.

[0025] The beneficial effects of the above technical solution are:

[0026] (1) Modifying organosilicon elastomer with hollow glass nanospheres can effectively improve the toughness and elongation of organosilicon matrix and reduce the Young's modulus of material to make it softer.

[0027] (2) The addition of hollow glass nanospheres improves its thermal stability;

[0028] (3) The nanospheres of hollow glass are highly hydrophilic, which can improve the water vapor permeability of silicone elastomers;

[0029] (4) The chemical inertness of hollow glass nanospheres combined with the biocompatibility of organosilicon matrix makes them suitable for medical-grade artificial skin. Attached Figure Description

[0030] Figure 1 The elastomer elongation (%) and toughness (kJ / m) of hollow glass with different nanosphere contents (0%, 0.5%, 1%, 1.5%, 2%) are shown. 3 In comparison, the tensile strength increased by 256.6% and the toughness increased by 637.6% when the addition amount was 1.5%.

[0031] Figure 2The graphs show the pressure versus Young's modulus of modified silicone elastomers with different proportions. They indicate that the Young's modulus decreased by 11.9% after adding 1.5% microspheres, thus improving the material's softness.

[0032] Figure 3 These are thermogravimetric analysis (TGA) curves of silicone elastomers modified with different proportions. After adding microspheres, the thermogravimetric temperature increased from 400℃ to 440℃, indicating enhanced thermal stability.

[0033] Figure 4 The test results show that the water vapor transmission rate of modified silicone elastomers with different proportions is 43.9% higher when the elastomer thickness is 500 μm. The results indicate that the addition of 2% microspheres increases the water vapor transmission rate by 43.9% compared to traditional materials. Detailed Implementation

[0034] To facilitate a better understanding of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all examples. Based on the embodiments of the present invention, all other examples obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Sample determination method:

[0036] The samples were prepared in a dumbbell shape, and the mechanical properties of the silicone elastomers were characterized using a universal testing machine at room temperature. Tensile measurements were performed at a tensile speed of 100 mm / min. The elastic modulus was calculated from the linear region (ε = 0-25%) of the tensile-strain curve. The toughness of the silicone elastomers was calculated as the area under the tensile-strain curve.

[0037] To characterize the thermogravimetric analysis of the sample, approximately 5 mg of colloidal sample was weighed, placed in a crucible, and then placed in the sample chamber. The temperature was increased at a rate of 10 K / min within the range of 35–800 °C, and the sample was measured under the condition of N2 as a protective gas and a gas flow rate of 30 ml / min.

[0038] Water vapor transmission rate was determined according to the moisture absorption method specified in the moisture permeability test. The inner diameter of the drying cylinder was (35.7±0.1) mm (cross-sectional area was 10 cm²). 2 Cut the patch to the same size and attach it to the top of the cylinder. Each cylinder has a flange at both ends, and each can hold 20 mL of deionized water. Place the treated sample in a drying oven at 37°C for 24 hours. Calculate the water vapor transmission rate (MVTR) using the following formula: X = (W1 - W2) × 1000 × 24 / T (in grams per square meter per 24 hours). 2 ·24h)] indicates.

[0039] Example 1

[0040] a. Mix MQ silicone resin solution with terminal vinyl silicone oil and stir thoroughly for 10 min to obtain the base adhesive. The MQ silicone resin solution has a mass fraction of 50% and an M / Q value of 0.8.

[0041] b. Thoroughly mix the base adhesive obtained in step a with the hollow glass nanosphere suspension for 20 minutes to obtain a mixed colloid of a certain viscosity. The mass fraction of the hollow glass nanosphere suspension is 10%, and the mass of the hollow glass nanospheres is 0.5% of the total mass of the base adhesive.

[0042] c. Divide the mixed colloid obtained in step b into two parts. Add a catalyst to one part and mix thoroughly to obtain component A; add hydrogen-containing silicone oil and an inhibitor to the other part and mix thoroughly to obtain component B. The ratio of the molar amount of hydrogen to the molar amount of vinyl groups in the added hydrogen-containing silicone oil and vinyl silicone oil is 1:1. The catalyst concentration is preferably 10 ppm, and the amount of inhibitor added is 0.1% of the total mass of the mixed colloid.

[0043] d. Mix components A and B thoroughly, place the mixture into a polytetrafluoroethylene mold, degas, and cure at 100℃ for 30 min. An elastomer with a thickness of 0.5 mm is obtained. Its tensile-strain curve is measured, thermogravimetric characterization is performed, and water vapor transmission rate is tested. The results are as follows: Figures 1-4 .

[0044] Example 2

[0045] a. Mix MQ silicone resin solution with terminal vinyl silicone oil and stir thoroughly for 10 min to obtain the base adhesive. The MQ silicone resin solution has a mass fraction of 50% and an M / Q value of 0.8.

[0046] b. Thoroughly mix the base adhesive obtained in step a with the hollow glass nanosphere suspension for 20 minutes to obtain a mixed colloid with a certain viscosity. The mass fraction of the hollow glass nanosphere suspension is 10%, and the mass of the hollow glass nanospheres is 1% of the total mass of the base adhesive.

[0047] c. Divide the mixed colloid obtained in step b into two parts. Add a catalyst to one part and mix thoroughly to obtain component A; add hydrogen-containing silicone oil and an inhibitor to the other part and mix thoroughly to obtain component B. The ratio of the molar amount of hydrogen to the molar amount of vinyl groups in the added hydrogen-containing silicone oil and vinyl silicone oil is 1:1. The catalyst concentration is preferably 10 ppm, and the amount of inhibitor added is 0.1% of the total mass of the mixed colloid.

[0048] d. Mix components A and B thoroughly, place the mixture into a polytetrafluoroethylene mold, degas, and cure at 100℃ for 30 min. An elastomer with a thickness of 0.5 mm is obtained. Its tensile-strain curve is measured, thermogravimetric characterization is performed, and water vapor transmission rate is tested. The results are as follows: Figures 1-4 .

[0049] Example 3

[0050] a. Mix MQ silicone resin solution with terminal vinyl silicone oil and stir thoroughly for 10 min to obtain the base adhesive. The MQ silicone resin solution has a mass fraction of 50% and an M / Q value of 0.8.

[0051] b. Thoroughly mix the base adhesive obtained in step a with the hollow glass nanosphere suspension for 20 minutes to obtain a mixed colloid of a certain viscosity. The mass fraction of the hollow glass nanosphere suspension is 10%, and the mass of the hollow glass nanospheres is 1.5% of the total mass of the base adhesive.

[0052] c. Divide the mixed colloid obtained in step b into two parts. Add a catalyst to one part and mix thoroughly to obtain component A; add hydrogen-containing silicone oil and an inhibitor to the other part and mix thoroughly to obtain component B. The ratio of the molar amount of hydrogen to the molar amount of vinyl groups in the added hydrogen-containing silicone oil and vinyl silicone oil is 1:1. The catalyst concentration is preferably 10 ppm, and the amount of inhibitor added is 0.1% of the total mass of the mixed colloid.

[0053] d. Mix components A and B thoroughly, place the mixture into a polytetrafluoroethylene mold, degas, and cure at 100℃ for 30 min. An elastomer with a thickness of 0.5 mm is obtained. Its tensile-strain curve is measured, thermogravimetric characterization is performed, and water vapor transmission rate is tested. The results are as follows: Figures 1-4 .

[0054] Example 4

[0055] a. Mix MQ silicone resin solution with terminal vinyl silicone oil and stir thoroughly for 10 min to obtain the base adhesive. The MQ silicone resin solution has a mass fraction of 50% and an M / Q value of 0.8.

[0056] b. Thoroughly mix the base adhesive obtained in step a with the hollow glass nanosphere suspension for 20 minutes to obtain a mixed colloid of a certain viscosity. The mass fraction of the hollow glass nanosphere suspension is 10%, and the mass of the hollow glass nanospheres is 1.5% of the total mass of the base adhesive.

[0057] c. Divide the mixed colloid obtained in step b into two parts. Add a catalyst to one part and mix thoroughly to obtain component A; add hydrogen-containing silicone oil and an inhibitor to the other part and mix thoroughly to obtain component B. The ratio of the molar amount of hydrogen to the molar amount of vinyl groups in the added hydrogen-containing silicone oil and vinyl silicone oil is 1:1. The catalyst concentration is preferably 10 ppm, and the amount of inhibitor added is 0.1% of the total mass of the mixed colloid.

[0058] d. Mix components A and B thoroughly, place the mixture into a polytetrafluoroethylene mold, degas, and cure at 100℃ for 30 min. An elastomer with a thickness of 0.5 mm is obtained. Its tensile-strain curve is measured, thermogravimetric characterization is performed, and water vapor transmission rate is tested. The results are as follows: Figures 1-4 .

[0059] Comparative Example 1

[0060] a. Mix MQ silicone resin solution with terminal vinyl silicone oil and stir thoroughly for 10 min to obtain the base adhesive. The MQ silicone resin solution has a mass fraction of 50% and an M / Q value of 0.8.

[0061] b. Divide the base colloid obtained in step a into two parts. Add a catalyst to one part and mix thoroughly to obtain component A; add hydrogen-containing silicone oil and an inhibitor to the other part and mix thoroughly to obtain component B. The ratio of the molar amount of hydrogen to the molar amount of vinyl groups in the added hydrogen-containing silicone oil and vinyl silicone oil is 1:1. The catalyst concentration is preferably 10 ppm, and the amount of inhibitor added is 0.1% of the total mass of the mixed colloid.

[0062] c. Mix components A and B thoroughly, place the mixture into a polytetrafluoroethylene mold, degas again, and cure at 100℃ for 30 min. An elastomer with a thickness of 0.5 mm is obtained. Its tensile-strain curve is measured, thermogravimetric characterization is performed, and water vapor transmission rate is tested. The results are as follows: Figures 1-4 .

Claims

1. A hollow glass nanosphere-modified organosilicon elastomer and its preparation method, characterized in that... The modified organosilicon elastomer for insulating glass nanospheres is composed of the following raw materials in the following mass ratios: 60-90% vinyl silicone oil, 0.1-10% hydrogen-containing silicone oil, 1-20% MQ silicone resin solution, 1-50 ppm catalyst, 0.05-0.3% inhibitor, and 5-20% solvent, and 0.1-5% insulating glass nanosphere suspension.

2. The MQ silicone resin solution of claim 1 is prepared by mixing MQ silicone resin with a non-toxic and non-irritating solvent, and its mass fraction is 10-50%. Wherein, MQ silicone resin is prepared by the hydrolysis and condensation of tetraethyl orthosilicate; the m / q value of MQ silicone resin is between 0.5 and 1.

0. The M / Q value refers to the molar ratio of monofunctional siloxane units (M units) to tetrafunctional siloxane units (Q units).

3. The vinyl silicone oil of claim 1 is a methyl silicone oil with terminal or side groups, and a viscosity of 10,000 to 100,000 mPa·s; the vinyl content in the vinyl silicone oil is 0.05 to 0.25%.

4. The hydrogen content in the hydrogen-containing silicone oil according to claim 1 is 0.2-1%, the molecular weight is 1000-5000, and the viscosity is 50-500 cst.

5. The catalyst according to claim 1 is one or more of the following: a cassiterite catalyst, a platinum-divinyltetramethyldisiloxane complex, a chloroplatinic acid solution, and a silicone oil dilution solution.

6. The inhibitor of claim 1 is one or more of methylbutynol, ethynylcyclohexanol and 1-ethynyl-1-cyclohexanol, methylpentynol and benzotriazole.

7. The solvent of claim 1 is one or more of volatile silicone oil or other non-toxic and non-irritating solutions.

8. The hollow glass nanospheres of claim 1 are submicron-sized microspheres with a hollow structure made of silicon dioxide, with a density of 0.1-2 g / cm3, a mass fraction of 15-30%, a particle size distribution of 70-100%: 100-1000 nm, and a pH value of 7-10.

9. The method for preparing the hollow glass nanosphere suspension according to claim 1 is as follows: mixing the hollow glass nanospheres with a solvent and sonicating for 30 min; wherein, The mass fraction of the hollow glass nanosphere suspension is 10-30%.

10. The method for preparing the hollow glass nanosphere modified organosilicon elastomer according to claim 1, comprising the following steps: a. Mix MQ silicone resin solution with vinyl silicone oil and stir thoroughly for 10-20 minutes to obtain the base adhesive; b. Thoroughly mix the base adhesive obtained in step a with the hollow glass nanosphere suspension for 10-30 minutes to obtain a mixed colloid of a certain viscosity. The mass of the hollow glass nanospheres accounts for 0.1-5% of the total mass of the base adhesive. c. Divide the mixed colloid obtained in step b into two parts. Add a catalyst to one part and mix thoroughly to obtain component A; add hydrogen-containing silicone oil and an inhibitor to the other part and mix thoroughly to obtain component B. The ratio of the molar amount of hydrogen to the molar amount of vinyl groups in the added hydrogen-containing silicone oil and vinyl silicone oil is 0.5 to 3:1, preferably 0.5 to 1.5:

1. The catalyst concentration is preferably 10 to 30 ppm, and the amount of inhibitor added is 0.1 to 2% of the total mass of the mixed colloid. d. Mix components A and B thoroughly, place in an easily degassed mold, degas, and cure at 30–120℃ for 10–30 minutes. The resulting elastomer will have a thickness of 0.02–1 mm. The elastomer thickness can be adjusted flexibly according to actual application requirements.

11. The easy-release mold according to claim 10 is made of non-stick materials such as polypropylene, high-density polyethylene, polycarbonate, ABS, polytetrafluoroethylene or fluorinated release film.

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