Oil-resistant high-foaming-rate silicone rubber foam material and preparation method thereof

Abstract

The invention discloses an oil-resistant high-foaming-rate silicone rubber foam material and a preparation method thereof.The silicone rubber foam material is prepared from a component A and a component B, and the mass ratio of the component A to the component B is 1: 1; the component A is prepared from the following raw materials in parts by weight: 20 to 100 parts of phenyl-containing alpha, omega-dihydroxy polydiorganosiloxane, 10 to 60 parts of modified vinyl silicone oil, 20 to 80 parts of hydrogen-containing silicone oil, 10 to 80 parts of filler and 0.1 to 3 parts of inhibitor; the component B is prepared from the following raw materials in parts by weight: 20 to 100 parts of phenyl-containing alpha, omega-dihydroxyl polydiorganosiloxane, 10 to 60 parts of modified vinyl silicone oil, 5 to 20 parts of hydroxyl silicone oil, 10 to 80 parts of filler and 0.1 to 5 parts of platinum catalyst. The silicone rubber foam material disclosed by the invention has the advantages of high foaming ratio, good high-temperature oil resistance, good stability of mechanical properties, good rebound resilience, foaming at normal temperature, no need of heating curing, simple process and the like.

Description

Technical Field

[0001] The invention relates to the technical field of silicone rubber foam materials, and in particular to an oil-resistant high-foaming-rate silicone rubber foam material and a preparation method thereof. Background Art

[0002] Foamed silicone rubber material is a porous polymer elastomer that has the advantages of ordinary silicone rubber and is also characterized by light weight, cushioning, shock absorption, and resistance to compression deformation. Therefore, it is widely used in electronics, automobiles, aviation, and daily life.

[0003] As foaming materials become more and more diversified, the market's performance requirements for foaming materials are further improved. When used in areas with more contact with solvents, such as automotive lubrication systems, electronic appliances, etc., foaming materials will swell at high temperatures, and the spatial structure will be destroyed, resulting in a significant reduction in its mechanical properties. On the other hand, due to the fast foaming speed of room temperature foam silicone rubber, it is easy to defoam, resulting in a low foaming ratio, and the foam material has poor cell stability. After cooling, the cells are prone to collapse, affecting its processing and practical application. Therefore, it is necessary to increase the foaming ratio of foaming materials and their oil resistance at high temperatures to expand their application areas. Summary of the invention

[0004] In view of the above-mentioned shortcomings that currently exist, the present invention provides an oil-resistant high foaming rate silicone rubber foam material and a preparation method thereof. The silicone rubber foam material of the present invention has the advantages of high foaming rate, good high-temperature oil resistance, good stability of mechanical properties, good resilience, foaming at room temperature, no need for heating and curing, and simple process.

[0005] In order to achieve the above object, the present invention provides an oil-resistant high-foaming rate silicone rubber foam material, wherein the oil-resistant high-foaming rate silicone rubber foam material is prepared from component A and component B, wherein the mass ratio of component A to component B is 1:1;

[0006] The component A is prepared from the following raw materials in parts by weight: 20-100 parts of α,ω-dihydroxy polydiorganosiloxane containing phenyl, 10-60 parts of modified vinyl silicone oil, 20-80 parts of hydrogen-containing silicone oil, 10-80 parts of filler, and 0.1-3 parts of inhibitor;

[0007] The B component is prepared from the following raw materials in parts by weight: 20-100 parts of phenyl-containing α, ω-dihydroxy polydiorganosiloxane, 10-60 parts of modified vinyl silicone oil, 5-20 parts of hydroxy silicone oil, 10-80 parts of filler, and 0.1-5 parts of platinum catalyst.

[0008] According to one aspect of the present invention, the structural formula of the modified vinyl silicone oil is: CH2=CH-Si(CH3)2-O-[Si(CH3)(CH2CH2CF3)-O] m-[Si(CH3)2-O] n -Si(CH3)2-CH=CH2; wherein the mass of the m segment accounts for 5-60wt.% of the mass of the modified vinyl silicone oil, and the mass of the n segment accounts for 10-80wt.% of the mass of the modified vinyl silicone oil.

[0009] According to one aspect of the present invention, the viscosity of the phenyl-containing α,ω-dihydroxy polydiorganosiloxane is 8000-500000 mm 2 / s; the hydrogen content in the hydrogen-containing silicone oil is 0.36-1.6wt.%; the hydroxyl content in the hydroxyl silicone oil is 5-15wt.%.

[0010] According to one aspect of the present invention, the filler is at least one of white carbon black, calcium carbonate, kaolin, barium sulfate, aluminum hydroxide, silica powder, mica powder, diatomaceous earth, organic clay, titanium dioxide, silicon dioxide, aluminum oxide, zinc oxide and hollow glass microspheres.

[0011] According to one aspect of the present invention, the inhibitor is at least one of 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol, 1-ethynyl-1-cyclohexanol, 3,5-dimethyl-1-hexyn-3-ol, diethyl fumarate and dibutyl fumarate.

[0012] Based on the same inventive concept, the present invention also provides a method for preparing any of the above-mentioned oil-resistant high-foaming-rate silicone rubber foam materials, comprising the following steps:

[0013] S1. Trifluoropropylmethylcyclotrisiloxane, dimethylcyclosiloxane and 1,3-divinyltetramethyldisiloxane are mixed, (CH3)4NOH catalyst is added under an inert atmosphere at 100-130°C, and the mixture is stirred for reaction for 4h-5h to obtain modified vinyl silicone oil;

[0014] S2, putting phenyl-containing α, ω-dihydroxy polydiorganosiloxane and modified vinyl silicone oil into a planetary mixer, and stirring them evenly under vacuum; then putting filler, hydrogen-containing silicone oil, and inhibitor into the planetary mixer, vacuuming, degassing and mixing, to obtain component A;

[0015] S3, putting phenyl-containing α, ω-dihydroxy polydiorganosiloxane and modified vinyl silicone oil into a planetary mixer, and stirring them evenly under vacuum; then putting filler, hydroxy silicone oil, and platinum catalyst into the planetary mixer, vacuuming, degassing and mixing, to obtain component B;

[0016] S4. Mix components A and B in a mass ratio of 1:1 and pour into a mold to foam at room temperature.

[0017] According to one aspect of the present invention, the mass ratio of trifluoropropylmethylcyclotrisiloxane to dimethylcyclosiloxane is 1:1-3.5; the mass ratio of 1,3-divinyltetramethyldisiloxane to trifluoropropylmethylcyclotrisiloxane is 1:20-60.

[0018] According to one aspect of the present invention, the mass ratio of trifluoropropylmethylcyclotrisiloxane to catalyst is 1:0.1%-0.4%.

[0019] According to one aspect of the present invention, the inert atmosphere is nitrogen or an inert gas.

[0020] Beneficial effects of the present invention:

[0021] (1) The present invention reacts modified vinyl silicone oil, phenyl-containing α, ω-dihydroxy polydiorganosiloxane with hydrogen-containing silicone oil at room temperature, and -F groups and phenyl groups are cross-linked and distributed in the three-dimensional skeleton of the foamed silicone rubber to form a complex spatial network structure, which is more conducive to capturing small gas molecules and is not easy to defoam, thereby improving the foaming ratio of the foamed silicone rubber;

[0022] (2) The -F group introduced into the modified vinyl silicone oil of the present invention can effectively prevent the infiltration of non-polar oil media, improve the oil resistance of the foamed silicone rubber, and thus maintain its mechanical properties for a long time;

[0023] (3) The phenyl-containing α,ω-dihydroxy polydiorganosiloxane of the present invention introduces phenyl groups to improve the high temperature resistance of silicone rubber. The rigid groups make the cured network structure strong enough to support the pore structure, so that the pores are not easy to collapse. At the same time, due to the increased surface tension, it is more conducive to forming a uniform and dense low-density foam, thereby improving the resilience of the colloid.

[0024] (4) The foamed silicone rubber material prepared by the present invention only needs to mix component A and component B and foam at room temperature without heating and curing. The process is simple and the production efficiency is improved. DETAILED DESCRIPTION

[0025] To make the present invention easier to understand, the present invention is further described below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present invention and are not used to limit the scope of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention. Unless otherwise defined, the professional terms used below are consistent with the meanings understood by professional and technical personnel in the field; unless otherwise specified, the raw materials and reagents involved in this article can be purchased from the market or prepared by known methods.

[0026] Example 1

[0027] A method for preparing an oil-resistant high-foaming-rate silicone rubber foam material comprises the following steps:

[0028] (1) 88 parts of trifluoropropylmethylcyclotrisiloxane, 100 parts of dimethylcyclosiloxane and 2 parts of 1,3-divinyltetramethyldisiloxane were placed in a round-bottom three-necked flask, placed in a constant temperature oil bath, and nitrogen was introduced for protection. The temperature was raised to 120°C, and 0.2 parts of (CH3)4NOH catalyst was added dropwise. The reaction was stirred for 4 hours, and the mixture was cooled to room temperature and taken out to obtain modified vinyl silicone oil.

[0029] (2) 63 parts of α,ω-dihydroxy polydiorganosiloxane containing phenyl (viscosity 20000 mm 2 / s), 30 parts of modified vinyl silicone oil are put into a planetary mixer and stirred evenly under vacuum. Then 20 parts of fumed silica, 15 parts of aluminum hydroxide, 35 parts of hydrogen-containing silicone oil and 1 part of inhibitor (1-ethynyl-1-cyclohexanol) are put into a planetary mixer, vacuumed, degassed and mixed to obtain component A;

[0030] (3) 77 parts of α,ω-dihydroxy polydiorganosiloxane containing phenyl (viscosity 20000 mm 2 / s), 40 parts of modified vinyl silicone oil are put into a planetary mixer and stirred evenly under vacuum. Then 20 parts of fumed silica, 15 parts of aluminum hydroxide, 10 parts of hydroxy silicone oil and 2 parts of platinum catalyst are put into a planetary mixer, vacuumed, degassed and mixed to obtain component B;

[0031] (4) Mix components A and B in a mass ratio of 1:1 and foam at room temperature.

[0032] Example 2

[0033] A method for preparing an oil-resistant high-foaming-rate silicone rubber foam material comprises the following steps:

[0034] (1) 40 parts of trifluoropropylmethylcyclotrisiloxane, 85 parts of dimethylcyclosiloxane and 1.5 parts of 1,3-divinyltetramethyldisiloxane were placed in a round-bottom three-necked flask, placed in a constant temperature oil bath, and nitrogen was introduced for protection. The temperature was raised to 120°C, and 0.1 parts of (CH3)4NOH catalyst was added dropwise. The reaction was stirred for 4 hours, and the mixture was cooled to room temperature and taken out to obtain modified vinyl silicone oil.

[0035] (2) 47 parts of α,ω-dihydroxy polydiorganosiloxane containing phenyl (viscosity 80000 mm 2 / s), 10 parts of modified vinyl silicone oil are put into a planetary mixer and stirred evenly under vacuum. Then 10 parts of diatomaceous earth, 10 parts of silicon powder, 25 parts of hydrogen-containing silicone oil, and 0.5 parts of inhibitor (3-methyl-1-pentyn-3-ol) are put into a planetary mixer, vacuumed, degassed and mixed to obtain component A;

[0036] (3) 53 parts of α,ω-dihydroxy polydiorganosiloxane containing phenyl (viscosity 80000 mm 2 / s), put 20 parts of modified vinyl silicone oil into a planetary mixer and stir evenly under vacuum. Then put 10 parts of diatomaceous earth, 10 parts of silicon powder, 8 parts of hydroxy silicone oil and 1.5 parts of platinum catalyst into the planetary mixer, vacuum degassing and mixing to obtain component B;

[0037] (4) Mix components A and B in a mass ratio of 1:1 and foam at room temperature.

[0038] Example 3

[0039] A method for preparing an oil-resistant high-foaming-rate silicone rubber foam material comprises the following steps:

[0040] (1) 30 parts of trifluoropropylmethylcyclotrisiloxane, 100 parts of dimethylcyclosiloxane and 1.5 parts of 1,3-divinyltetramethyldisiloxane were placed in a round-bottom three-necked flask, placed in a constant temperature oil bath, and nitrogen was introduced for protection. The temperature was raised to 120°C, and 0.1 parts of (CH3)4NOH catalyst was added dropwise. The reaction was stirred for 4 hours, and the mixture was cooled to room temperature and taken out to obtain modified vinyl silicone oil.

[0041] (2) 70 parts of α,ω-dihydroxy polydiorganosiloxane containing phenyl (viscosity 80000 mm 2 / s), 21 parts of modified vinyl silicone oil are put into a planetary mixer and stirred evenly under vacuum. Then 20 parts of silicon dioxide, 20 parts of mica powder, 35 parts of hydrogen-containing silicone oil and 0.5 parts of inhibitor (1-ethynyl-1-cyclohexanol) are put into a planetary mixer, vacuumed, degassed and mixed to obtain component A;

[0042] (3) 80 parts of α,ω-dihydroxy polydiorganosiloxane containing phenyl (viscosity 80000 mm 2 / s), 34 parts of modified vinyl silicone oil are put into a planetary mixer and stirred evenly under vacuum. Then 20 parts of silicon dioxide, 20 parts of mica powder, 10 parts of hydroxy silicone oil and 2.5 parts of platinum catalyst are put into a planetary mixer, vacuumed, degassed and mixed to obtain component B;

[0043] (4) Mix components A and B in a mass ratio of 1:1 and foam at room temperature.

[0044] Example 4

[0045] A method for preparing an oil-resistant high-foaming-rate silicone rubber foam material comprises the following steps:

[0046] (1) 36 parts of trifluoropropylmethylcyclotrisiloxane, 40 parts of dimethylcyclosiloxane and 1 part of 1,3-divinyltetramethyldisiloxane were placed in a round-bottom three-necked flask, placed in a constant temperature oil bath, and nitrogen was introduced for protection. The temperature was raised to 120°C, and 0.1 parts of (CH3)4NOH catalyst was added dropwise. The reaction was stirred for 4 hours, and the mixture was cooled to room temperature and taken out to obtain modified vinyl silicone oil.

[0047] (2) 73 parts of α,ω-dihydroxy polydiorganosiloxane containing phenyl (viscosity 20000 mm 2 / s), 30 parts of modified vinyl silicone oil are put into a planetary mixer and stirred evenly under vacuum. Then 25 parts of organic clay, 20 parts of calcium carbonate, 40 parts of hydrogen-containing silicone oil and 1 part of inhibitor (3-methyl-1-pentyn-3-ol) are put into a planetary mixer, vacuumed, degassed and mixed to obtain component A;

[0048] (3) 80 parts of α,ω-dihydroxy polydiorganosiloxane containing phenyl (viscosity 80000 mm 2 / s), 50 parts of modified vinyl silicone oil are put into a planetary mixer and stirred evenly under vacuum. Then 25 parts of organic clay, 20 parts of calcium carbonate, 12 parts of hydroxy silicone oil and 2 parts of platinum catalyst are put into a planetary mixer, vacuumed, degassed and mixed to obtain component B;

[0049] (4) Mix components A and B in a mass ratio of 1:1 and foam at room temperature.

[0050] Comparative Example 1

[0051] The difference between this comparative example and Example 1 is that the α,ω-dihydroxy polydiorganosiloxane (viscosity 20000mm) containing phenyl in component A and component B is added. 2 / s) was changed to α, ω-dihydroxy polydimethylsiloxane (107 silicone rubber, viscosity 20000mm 2 Other steps and parameters are the same as those in Example 1.

[0052] Comparative Example 2

[0053] A method for preparing a silicone rubber foam material comprises the following steps:

[0054] (1) 63 parts of α,ω-dihydroxy polydiorganosiloxane containing phenyl (viscosity 80000 mm 2 / s), put 20 parts of vinyl silicone oil into a planetary mixer and stir evenly under vacuum. Then put 20 parts of kaolin, 15 parts of silicon dioxide, 35 parts of hydrogen-containing silicone oil, and 1 part of inhibitor (3,5-dimethyl-1-hexyn-3-ol) into a planetary mixer, vacuum degassing and mixing to obtain component A;

[0055] (2) 77 parts of α,ω-dihydroxy polydiorganosiloxane containing phenyl (viscosity 80000 mm 2 / s), 30 parts of vinyl silicone oil are put into a planetary mixer and stirred evenly under vacuum. Then 20 parts of kaolin, 15 parts of silicon dioxide, 10 parts of hydroxy silicone oil and 2 parts of platinum catalyst are put into a planetary mixer, vacuumed, degassed and mixed to obtain component B;

[0056] (3) Mix components A and B in a mass ratio of 1:1 and foam at room temperature.

[0057] Comparative Example 3

[0058] (1) 68 parts of α,ω-dihydroxy polydiorganosiloxane containing phenyl (viscosity 80000 mm 2 / s), 20 parts of vinyl silicone oil, 5 parts of methyl fluorosilicone oil, put them into a planetary mixer, and stir them evenly under vacuum. Then put 20 parts of diatomaceous earth, 20 parts of calcium carbonate, 38 parts of hydrogen-containing silicone oil, and 1 part of inhibitor (1-ethynyl-1-cyclohexanol) into the planetary mixer, vacuum degassing and mixing to obtain component A;

[0059] (2) 82 parts of phenyl-containing α,ω-dihydroxy polydiorganosiloxane (viscosity 80000 mm2 / s), 33 parts of vinyl silicone oil, and 5 parts of methyl fluorosilicone oil were added to a planetary mixer and stirred evenly under vacuum. Then 20 parts of diatomaceous earth, 20 parts of calcium carbonate, 10 parts of hydroxy silicone oil, and 2 parts of platinum catalyst were added to the planetary mixer, and vacuum degassing and mixing were performed to obtain component B;

[0060] (3) Mix components A and B in a mass ratio of 1:1 and foam at room temperature.

[0061] Performance testing and result analysis:

[0062] The performance tests of Examples 1-4 and Comparative Examples 1-3 were carried out, wherein the Shore hardness: according to GB / T

[0063] 531-2008; Compression set: measured according to GB / T 6669-2008; Tensile strength: measured according to GB / T528-2009; Elongation at break: measured according to GB / T 528-2009; Oil resistance test: tested according to GB / T 1690-2006, test the performance data of resistance to 2# standard oil, the test conditions are: 150℃×72h, the test results are shown in Table 1 below:

[0064] Table 1:

[0065]

[0066]

[0067] By comparing the various properties of Examples 1-4 and Comparative Examples 1-3 in Table 1, it can be seen that the -F group and phenyl cross-linking in the oil-resistant high foaming rate silicone rubber foam material of the present invention are distributed in the three-dimensional skeleton of the foamed silicone rubber, which is conducive to capturing small gas molecules and is not easy to defoam, thereby improving the foaming ratio of the foamed silicone rubber. By comparing the various properties of Example 1 and Comparative Example 1 in Table 1, it can be seen that the introduction of phenyl in the oil-resistant high foaming rate silicone rubber foam material of the present invention can improve the uniformity of the pores of the foamed silicone rubber, and the rigid group effectively prevents the collapse of the pores, thereby improving the mechanical properties and resilience of the colloid. By comparing the various properties of Examples 1-4 and Comparative Example 2 in Table 1, it can be seen that the introduction of the -F group in the oil-resistant high foaming rate silicone rubber foam material of the present invention can effectively improve the high temperature oil resistance of the foamed silicone rubber, and with the increase of the -F group content, the high temperature oil resistance of the colloid can be further improved. By comparing the properties of Examples 1-4 and Comparative Example 3 in Table 1, it can be seen that the fluorinated silicone oil will slowly precipitate at high temperatures, reducing the high-temperature oil resistance of the foamed silicone rubber, while the -F group of the modified vinyl silicone oil is cross-linked in the network structure of the foamed silicone rubber through a silylation reaction, which can more effectively improve the high-temperature oil resistance of the colloid.

[0068] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the art within the technical scope disclosed in the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. An oil-resistant high foaming rate silicone rubber foam material, characterized in that: The oil-resistant high-foaming-rate silicone rubber foam material is prepared from component A and component B, and the mass ratio of component A to component B is 1:1; The component A is prepared from the following raw materials in parts by weight: 20-100 parts of α,ω-dihydroxy polydiorganosiloxane containing phenyl, 10-60 parts of modified vinyl silicone oil, 20-80 parts of hydrogen-containing silicone oil, 10-80 parts of filler, and 0.1-3 parts of inhibitor; The B component is prepared from the following raw materials in parts by weight: 20-100 parts of phenyl-containing α, ω-dihydroxy polydiorganosiloxane, 10-60 parts of modified vinyl silicone oil, 5-20 parts of hydroxy silicone oil, 10-80 parts of filler, and 0.1-5 parts of platinum catalyst.

2. The oil-resistant high foaming rate silicone rubber foam material according to claim 1, characterized in that: The structural formula of the modified vinyl silicone oil is: CH2=CH-Si(CH3)2-O-[Si(CH3)(CH2CH2CF3)-O] m -[Si(CH3)2-O] n -Si(CH3)2-CH=CH2; wherein the mass of the m segment accounts for 5-60wt.% of the mass of the modified vinyl silicone oil, and the mass of the n segment accounts for 10-80wt.% of the mass of the modified vinyl silicone oil.

3. The oil-resistant high foaming rate silicone rubber foam material according to claim 1, characterized in that: The viscosity of the phenyl-containing α,ω-dihydroxy polydiorganosiloxane is 8000-500000 mm 2 / s; the hydrogen content in the hydrogen-containing silicone oil is 0.36-1.6wt.%; the hydroxyl content in the hydroxyl silicone oil is 5-15wt.%.

4. The oil-resistant high foaming rate silicone rubber foam material according to claim 1, characterized in that: The filler is at least one of white carbon black, calcium carbonate, kaolin, barium sulfate, aluminum hydroxide, silicon powder, mica powder, diatomaceous earth, organic clay, titanium dioxide, silicon dioxide, aluminum oxide, zinc oxide and hollow glass microspheres.

5. The oil-resistant high foaming rate silicone rubber foam material according to claim 1, characterized in that: The inhibitor is at least one of 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol, 1-ethynyl-1-cyclohexanol, 3,5-dimethyl-1-hexyn-3-ol, diethyl fumarate and dibutyl fumarate.

6. The method for preparing the oil-resistant high foaming rate silicone rubber foam material according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Trifluoropropylmethylcyclotrisiloxane, dimethylcyclosiloxane and 1,3-divinyltetramethyldisiloxane are mixed, (CH3)4NOH catalyst is added under an inert atmosphere at 100-130°C, and the mixture is stirred for reaction for 4h-5h to obtain modified vinyl silicone oil; S2, putting phenyl-containing α, ω-dihydroxy polydiorganosiloxane and modified vinyl silicone oil into a planetary mixer, and stirring them evenly under vacuum; then putting filler, hydrogen-containing silicone oil, and inhibitor into the planetary mixer, vacuuming, degassing and mixing, to obtain component A; S3, putting phenyl-containing α, ω-dihydroxy polydiorganosiloxane and modified vinyl silicone oil into a planetary mixer, and stirring them evenly under vacuum; then putting filler, hydroxy silicone oil, and platinum catalyst into the planetary mixer, vacuuming, degassing and mixing, to obtain component B; S4. Mix components A and B in a mass ratio of 1:1 and pour into a mold to foam at room temperature.

7. The method for preparing the oil-resistant high foaming rate silicone rubber foam material according to claim 6, characterized in that: The mass ratio of the trifluoropropylmethylcyclotrisiloxane to the dimethylcyclosiloxane is 1:1-3.5; the mass ratio of the 1,3-divinyltetramethyldisiloxane to the trifluoropropylmethylcyclotrisiloxane is 1:20-60.

8. The oil-resistant high foaming rate silicone rubber foam material according to claim 6, characterized in that: The mass ratio of the trifluoropropylmethylcyclotrisiloxane to the catalyst is 1:0.1%-0.4%.

9. The oil-resistant high foaming rate silicone rubber foam material according to claim 6, characterized in that: The inert atmosphere is nitrogen or an inert gas.

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