Method, product and application for preparing wide-temperature-range damping silicone rubber by dissolution blending

Abstract

The present invention belongs to the field of silicone damping materials, and particularly relates to a method, product and application for preparing a wide-temperature-range damping silicone rubber by solution blending. Phenyl silicone rubber and MQ resin are dissolved in a solvent, stirred and mixed, and then the solvent is removed. After mixing with a reinforcing filler and standing, a vulcanizing agent is added and mixed. The obtained mixture is vulcanized to obtain a wide-temperature-range damping silicone rubber. Incorporating MQ resin into phenyl silicone rubber by solution blending promotes the formation of a larger molecular interpenetration and entanglement between phenyl silicone rubber and MQ resin, thereby forming more interfacial regions in the phenyl silicone rubber matrix, and improving the damping performance and mechanical strength of the composite material.

Description

Technical Field

[0001] The present invention belongs to the field of silicone damping materials, and particularly relates to a method, product and application for preparing a wide-temperature-range damping silicone rubber by solution blending. Background Art

[0002] Disclosing the information of this background art section is only intended to enhance the overall understanding of the present invention and is not necessarily to be regarded as an admission or any form of implication that this information constitutes the prior art already known to those of ordinary skill in the art.

[0003] Vibration is a common challenge in various fields such as mechanical engineering, construction, transportation, and aerospace, with potentially significant impacts. Especially in the aerospace field, the vibrations occurring during launch and orbital operation can severely damage the structural stability, disrupt the functions of critical instruments, and ultimately lead to a shortened service life of the spacecraft. Damping materials can effectively absorb and dissipate vibration energy, reduce noise, and minimize structural resonance, providing crucial protection for the spacecraft and its internal systems. Due to the urgent need for long-term functional stability and reliability under harsh environmental conditions, damping materials for aerospace applications must be lightweight, mechanically robust, and have excellent resistance to extreme temperatures, corrosion, and aging. Compared with traditional alloy-based damping materials, viscoelastic damping materials exhibit superior performance over a wider frequency range, while having lower density, better processability, stronger corrosion resistance, and lower cost. Therefore, viscoelastic damping materials have become the first choice for vibration control in aerospace applications.

[0004] Among viscoelastic damping materials, silicone rubber has obvious advantages over traditional rubbers due to its -Si-O-Si- backbone. On the one hand, the bond energy of the Si-O-Si bond (460 kJ / mol) is significantly higher than that of the C-C bond (346 kJ / mol). On the other hand, the Si-O-Si bond has a longer bond length and a larger bond angle. This unique structure endows silicone rubber with extraordinary resistance to extreme temperatures, weather resistance, anti-aging properties, and excellent elastic retention, making it particularly suitable for applications in harsh environments. However, the inherent flexibility of silicone rubber and its weak intermolecular interactions limit its damping performance. To improve the damping performance, introducing phenyl groups into silicone rubber can improve the damping characteristics, but it is still difficult to meet the effective damping under a wide temperature range.

[0005] The damping filler (damping additive) includes particulate, flaky, fibrous, and nanoscale fillers, which can be introduced into the silicone rubber matrix by mechanical blending to improve the damping performance of the silicone rubber. The previous patent 202410078263.8 synthesized MQ resin as a silicone rubber damping additive and incorporated it into phenyl silicone rubber by mechanical blending. Although the phenyl silicone rubber composite prepared by mechanical blending exhibits excellent damping performance, due to the only mechanical shear force existing in the mechanical blending method, it can only ensure the uniform dispersion of MQ resin in the silicone rubber. Only the surface hydroxyl groups and phenyl groups of MQ resin can interact with phenyl silicone rubber, making it difficult to achieve effective damping in high-temperature environments and being unfavorable for applications in harsh environments. Summary of the Invention

[0006] To solve the deficiencies of the prior art, the present invention provides a method, product, and application for preparing wide-temperature-range damping silicone rubber by solution blending. The present invention incorporates MQ resin into phenyl silicone rubber by solution blending, promoting the formation of greater molecular interpenetration and entanglement between phenyl silicone rubber and MQ resin, thereby forming more interfacial regions in the phenyl silicone rubber matrix and improving the damping performance and mechanical strength of the composite material.

[0007] To achieve the above object, the present invention is implemented through the following technical solutions:

[0008] In the first aspect, the present invention provides a method for preparing wide-temperature-range damping silicone rubber by solution blending, including the following steps:

[0009] Dissolve phenyl silicone rubber and MQ resin in a solvent, stir and mix, then remove the solvent, mix with a reinforcing filler, let stand, add a vulcanizing agent and mix, and vulcanize the obtained mixture to obtain wide-temperature-range damping silicone rubber;

[0010] The molar ratio of M / Q of the MQ resin is 0.5 - 0.9, and the structure of the M unit is , where R 1 , R 2 , R 3 are independently selected from one of alkyl and aryl, and at least one of R 1 , R 2 , R 3 is aryl.

[0011] Preferably, the mass ratio of the MQ resin to the silicone rubber is (0.2 - 0.4):1.

[0012] Preferably, the alkyl is an alkyl with 1 - 6 carbon atoms, and the aryl is phenyl or biphenyl.

[0013] Preferably, the preparation method of the MQ resin includes the following steps:

[0014] Tetraethyl orthosilicate, water, an acid catalyst, and a solubilizer are stirred and mixed, and then M monomer is added dropwise for reaction. After the reaction is completed, toluene is added. The obtained toluene solution of MQ resin is washed with deionized water, the solvent is removed, washed with ethanol, and dried to obtain MQ resin.

[0015] Further preferably, the acid catalyst includes hydrochloric acid, and the solubilizer includes ethanol.

[0016] Further preferably, the reaction temperature is 60 - 80 °C, and the reaction time is 3 - 5 h.

[0017] Preferably, the phenyl silicone rubber includes monophenyl silicone rubber, and the phenyl content of the phenyl silicone rubber is 20 - 40 mol%.

[0018] Preferably, the reinforcing filler includes fumed silica, the vulcanizing agent includes bis(2,4), and the mass ratio of the reinforcing filler, vulcanizing agent to the silicone rubber is (0.4 - 0.6):(0.01 - 0.03):1.

[0019] Preferably, the solvent includes dichloromethane.

[0020] Preferably, the silicone rubber and MQ resin are dissolved in the solvent and stirred and mixed at room temperature for 12 - 36 h; after mixing with the reinforcing filler, it is left standing at room temperature for 12 - 36 h.

[0021] Preferably, vulcanization includes primary vulcanization and secondary vulcanization; the temperature of primary vulcanization is 100 - 120 °C, the pressure is 5 - 15 MPa, and the time is 5 - 15 min; the temperature of secondary vulcanization is 170 - 190 °C, and the time is 3 - 5 h.

[0022] In a second aspect, the present invention provides a wide - temperature - range damping silicone rubber obtained by the method as described in the first aspect.

[0023] In a third aspect, the present invention provides the application of the wide - temperature - range damping silicone rubber as described in the second aspect in the preparation of damping materials and / or damping devices.

[0024] The beneficial effects obtained by one or more of the above - mentioned technical solutions of the present invention are as follows:

[0025] In the present invention, MQ resin is incorporated into phenyl silicone rubber by dissolution and blending, avoiding the aggregation of MQ resin caused by mechanical blending, promoting the formation of more significant molecular interpenetration and entanglement between phenyl silicone rubber and MQ resin, so that a thicker tightly - bound rubber layer and loosely - bound rubber layer are formed in the composite material, thereby expanding the interfacial area and generating more interfacial effects, improving the damping performance and mechanical strength of the composite material.

[0026] The present invention prepares a wide-temperature-range damping silicone rubber through solution blending. Compared with the damping silicone rubber prepared by mechanical blending, the wide-temperature-range damping silicone rubber has a wider damping temperature range with Tanδ>0.3 and a damping temperature range with Tanδ>0.2, can effectively buffer the impact when a steel ball falls, and has more excellent mechanical properties, meeting the anti-vibration requirements in harsh environments and broadening the application fields of silicone rubber materials.

[0027] The present invention further regulates the M / Q molar ratio in the MQ resin, demonstrating the universality of solution blending for different MQ resins, and pointing out the direction for further modification of wide-temperature-range high-damping silicone rubber. Description of the Drawings

[0028] The attached drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0029] Figure 1 DMA curves of the wide-temperature-range high-damping silicone rubber in Examples 1 to 5, MBDC in Comparative Example 1, and blank silicone rubber in Comparative Example 2;

[0030] Figure 2 Stress-strain curves of the wide-temperature-range high-damping silicone rubber in Examples 1 to 5, MBDC in Comparative Example 1, and blank silicone rubber in Comparative Example 2;

[0031] Figure 3 Crosslinking chain densities of the wide-temperature-range high-damping silicone rubber in Examples 1 to 5, MBDC in Comparative Example 1, and blank silicone rubber in Comparative Example 2;

[0032] Figure 4 AFM modulus images of (a) DBDC in Example 1, (b) MBDC in Comparative Example 1, and (c) blank silicone rubber in Comparative Example 2;

[0033] Figure 5 DSC curves of (a) unvulcanized DBDC in Example 1, (b) unvulcanized MBDC in Comparative Example 1, and (c) phenyl silicone rubber raw rubber;

[0034] Figure 6 Modulus displacement curves of the dashed-line marked interface regions in the AFM-QNM modulus images of (a) DBDC in Example 1, (b) MBDC in Comparative Example 1, and (c) blank silicone rubber in Comparative Example 2 and the AFM-QNM modulus images of (d) DBDC in Example 1, (e) MBDC in Comparative Example 1, and (f) blank silicone rubber in Comparative Example 2;

[0035] Figure 7 Schematic diagram of the damping enhancement mechanism of DBDC. Detailed Embodiments

[0036] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in combination with specific examples and comparative examples.

[0037] Example 1

[0038] 208 g of tetraethyl orthosilicate, 120 mL of water, 12 mL of concentrated hydrochloric acid (mass fraction of 36%) and 50 g of ethanol were stirred and mixed, and then 185.6 g (molar amount is 80% of tetraethyl orthosilicate) of diphenylmethylchlorosilane was added dropwise. The reaction was carried out by stirring at 70 °C for 4 hours. After the reaction, toluene was added to promote the extraction of MQ resin. The toluene solution of MQ resin was washed with deionized water until the natural pH value was reached. The toluene solvent was removed using a rotary evaporator, and then washed three times with absolute ethanol, and then dried in an oven to obtain MQ resin, denoted as 0.8M / Q.

[0039] 100 parts by weight of phenyl silicone rubber (phenyl content is 30 mol%) and 30 parts by weight of MQ resin (0.8M / Q) were dissolved in dichloromethane and stirred and mixed at room temperature for 24 hours, and then the solvent dichloromethane was removed using an oven; the above mixture and 50 parts by weight of fumed silica were added to a dense refining machine and fully mixed at room temperature, and then passed through a perforator for 5 minutes and allowed to stand for 24 hours; finally, 2 parts by weight of bis(2,4) was added using a two-roll open mill at 25 °C to obtain a mixture. The mixture was transferred to a metal mold and vacuum vulcanized at 110 °C and 10 MPa for 10 minutes using a vacuum plate vulcanizer, and then secondarily vulcanized in a blast furnace at 180 °C for 4 hours to obtain a wide-temperature-range high-damping silicone rubber, denoted as DBDC.

[0040] Example 2

[0041] Differing from Example 1, 116 g (molar amount is 50% of tetraethyl orthosilicate) of diphenylmethylchlorosilane was added dropwise, and the obtained MQ resin was denoted as 0.5M / Q, and 0.5M / Q was used to prepare a wide-temperature-range high-damping silicone rubber.

[0042] Example 3

[0043] Differing from Example 1, 139.2 g (molar amount is 60% of tetraethyl orthosilicate) of diphenylmethylchlorosilane was added dropwise, and the obtained MQ resin was denoted as 0.6M / Q, and 0.6M / Q was used to prepare a wide-temperature-range high-damping silicone rubber.

[0044] Example 4

[0045] Different from Example 1, 162.4 g of diphenylmethylchlorosilane (70% of the molar amount of tetraethyl orthosilicate) was added dropwise, and the obtained MQ resin was denoted as 0.7M / Q. 0.7M / Q was used to prepare the wide-temperature-range high-damping silicone rubber.

[0046] Example 5

[0047] Different from Example 1, 208.8 g of diphenylmethylchlorosilane (90% of the molar amount of tetraethyl orthosilicate) was added dropwise, and the obtained MQ resin was denoted as 0.9M / Q. 0.9M / Q was used to prepare the wide-temperature-range high-damping silicone rubber.

[0048] The MQ resins with different M / Q molar ratios were characterized, and the results are shown in Table 1. As the M / Q molar ratio increases, the molecular weight and particle size of the MQ resin decrease.

[0049] Table 1 Parameters of different MQ resins

[0050]

[0051] The wide-temperature-range high-damping silicone rubbers obtained in Examples 1-5 were subjected to dynamic mechanical tests in the tensile mode, at 1 Hz, and at different temperatures, as Figure 1 shown. The variation trend of the damping coefficient of the wide-temperature-range high-damping silicone rubbers prepared with different MQ resins with temperature is the same. The damping performance first increases and then decreases with the increase of the M / Q molar ratio, and reaches the peak when the M / Q molar ratio is 0.8. Further, the stress-strain test of the wide-temperature-range high-damping silicone rubber was carried out, as Figure 2 shown. The mechanical properties also show a trend of first increasing and then decreasing with the increase of the M / Q molar ratio and reach the peak when the M / Q molar ratio is 0.8. The M monomer (such as diphenylmethylchlorosilane) is used as a capping agent. Increasing the M monomer will reduce the molecular weight and particle size of the MQ resin, and at the same time will also reduce its crosslinking density, making the MQ resin have higher solubility and enabling greater interpenetration and entanglement with the phenyl silicone rubber chain during the solvent blending process. In addition, with the increase of the M / Q molar ratio, the phenyl content in the MQ resin will also increase, thereby enhancing the π-π interaction between the MQ resin and the phenyl silicone rubber. The stronger interaction significantly improves the damping and mechanical properties of the wide-temperature-range high-damping silicone rubber. However, when the M / Q molar ratio becomes too high, the molecular weight of the MQ resin decreases too much, resulting in too small a resin core to provide sufficient mechanical strength and possibly damaging the damping performance at high temperatures, thus limiting the effectiveness of the wide-temperature-range high-damping silicone rubber.

[0052] Comparative Example 1

[0053] 100 parts by weight of phenyl silicone rubber (phenyl content: 30 mol%) and 50 parts by weight of fumed silica were mixed in a Banbury mixer, and then transferred to a two-roll mill. At 25 °C, 30 parts by weight of MQ resin (0.8 M / Q) and 2 parts by weight of bis(2,4-dichlorobenzoyl) peroxide were added and mixed. The mixed rubber was transferred to a metal mold and vacuum-cured at 110 °C and 10 MPa for 10 minutes using a vacuum flat vulcanizer, and then post-cured in a forced-air oven at 180 °C for 4 hours to obtain a mechanically blended damping silicone rubber, denoted as MBDC.

[0054] Comparative Example 2

[0055] 100 parts by weight of phenyl silicone rubber (phenyl content: 30 mol%) and 50 parts by weight of fumed silica were added to a Banbury mixer and thoroughly mixed at room temperature. Then, it was passed through the two-roll mill thinly for 5 minutes and allowed to stand for 24 hours. Finally, 2 parts by weight of bis(2,4-dichlorobenzoyl) peroxide were added using the two-roll mill at 25 °C to obtain a mixed rubber. The mixed rubber was transferred to a metal mold and vacuum-vulcanized at 110 °C and 10 MPa for 10 minutes using a vacuum plate vulcanizer, and then post-cured in a forced-air oven at 180 °C for 4 hours to obtain a blank silicone rubber.

[0056] Dynamic mechanical tests were carried out on MBDC and the blank silicone rubber and compared with DBDC. The results are as Figure 1 shown. Near the glass transition temperature (Tg), the order of tanδ is: blank silicone rubber > MBDC > DBDC. However, at higher temperatures, the order is DBDC > MBDC > blank silicone rubber. When the temperature is lower than Tg, the phenyl silicone rubber is still in the glassy state, and the movement of its molecular chains is significantly restricted. As the temperature increases, the segments gradually change from the frozen state to the active state. The movement of the molecular chains needs to overcome the intermolecular cohesive force, resulting in the absorption and dissipation of energy. The addition of MQ resin introduces large phenyl groups, which further hinders the segmental movement of phenyl silicone rubber. Therefore, the tanδ of MBDC and DBDC near Tg is lower than that of the blank sample. Among them, DBDC is the lowest, which is attributed to the stronger molecular interpenetration and entanglement between MQ resin and phenyl silicone rubber, imposing greater restrictions on chain movement. Above Tg, the mobility of the phenyl silicone rubber chains increases, and the phenyl groups in the MQ resin generate π-π interactions and hydrogen bonds with the phenyl silicone rubber molecules, which can significantly improve the damping performance of the composite material. These interactions significantly improve the damping performance of the composite material. In addition, the interpenetration and entanglement between molecular chains generate more interfacial interactions, further improving the damping performance. DBDC has greater molecular interpenetration and entanglement between MQ resin and phenyl silicone rubber chains, resulting in an increase in its high-temperature tanδ. The damping temperature range with Tanδ > 0.3 and the damping temperature range with Tanδ > 0.2 are 139 °C and 235 °C respectively, which are significantly wider than 110 °C and 207 °C of MBDC.

[0057] As Figure 2 shown, the blank silicone rubber exhibits the highest tensile strength and Young's modulus, with a tensile strength of 10.1 MPa and an elongation at break of 340%; in contrast, MBDC has the lowest tensile strength of 6.5 MPa and an elongation at break of 380%; while DBDC shows improved mechanical properties compared to MBDC, with a tensile strength of 7 MPa and an elongation at break of 448%. Low-field nuclear magnetic resonance tests were carried out on the blank silicone rubber, MBDC and the wide-temperature-range high-damping silicone rubbers of Examples 1 to 5, and the crosslinking chain density was calculated. As Figure 3 shown, MBDC and the wide-temperature-range high-damping silicone rubbers have similar crosslinking densities and are both lower than that of the blank silicone rubber. Since the MQ resin does not participate in crosslinking, the mechanical properties of MBDC and the wide-temperature-range high-damping silicone rubbers are lower than those of the blank silicone rubber. However, the wide-temperature-range high-damping silicone rubbers contain more bound rubber, resulting in more interfacial effects and thus better mechanical properties than MBDC.

[0058] AFM modulus images ( Figure 4 ) show that the low-modulus regions correspond to the silicone rubber matrix, while the high-modulus regions correspond to the fillers. The smaller aggregates in the high-modulus regions are SiO 2 , and the larger aggregates are MQ resins. The distribution of SiO 2 and MQ resins in the phenyl silicone rubber forms a characteristic "island" structure. Both DBDC and MBDC show a relatively uniform distribution of MQ resins in the phenyl silicone rubber. The aggregates in MBDC are larger and more numerous, while the aggregates in DBDC are smaller and more evenly distributed. This difference is attributed to the solvent blending process, which allows the molecular chains of the MQ resin to interpenetrate and entangle with the phenyl silicone rubber chains, effectively dissolving part of the MQ resin in the matrix and reducing the number of aggregates. In contrast, the mechanical blending process does not involve solvents, resulting in larger MQ resin aggregates in MBDC.

[0059] Differential scanning calorimetry (DSC) was used to measure the heat capacity jump (ΔCp) of pure phenyl silicone rubber (uncured phenyl silicone rubber gum stock), MBDC (uncured compound) and DBDC (uncured compound) (the DSC curves are as Figure 5 shown). The Tg and ΔCp values of each sample were obtained from the DSC curves, and the normalized heat capacity jump (ΔC pn ) and the mass fraction of the polymer segments in the interfacial region (χ im ) were calculated using equations (1) and (2):

[0060] ΔC pn =ΔC p / (1 - )(1)

[0061] χ im =(ΔC p0 -ΔC pn ) / ΔC p0 (2)

[0062] In the formula, ω represents the mass fraction of the filler in the composite material, and ΔC p0 represents the heat capacity jump of pure phenyl silicone rubber near Tg.

[0063] Table 2 Tg, ΔC p 、ΔC pn and χ im

[0064]

[0065] As shown in Table 2, DBDC contains a higher proportion of polymer segments in the interfacial region. This indicates that the solution blending method helps to form more bound rubber between the MQ resin and phenyl silicone rubber, thus forming more interfacial regions in DBDC. As Figure 6 shown, AFM-QNM modulus images of blank silicone rubber, MBDC, and DBDC were obtained, and then quantitative analysis was performed on the interfacial regions marked by the dashed lines. The filler in the rubber can form a bound rubber (BR) layer with rubber molecules, and this bound rubber layer can be divided into a tightly bound rubber (TBR) layer formed by chemical adsorption and a loosely bound rubber (LBR) layer formed by physical adsorption and mechanical entanglement. In summary, the damping enhancement mechanism of DBDC is as Figure 7 shown. Compared with MBDC, DBDC prepared by solution blending shows a thicker bound rubber layer. During the preparation of DBDC, the MQ resin and phenyl silicone rubber are dissolved in an organic solvent, allowing their molecular chains to move freely. Under stirring, the mutual penetration and entanglement of molecular chains are promoted, while the aggregation of the MQ resin is reduced. Therefore, more interactions and hydrogen bonds occur between the MQ resin and phenyl silicone rubber. After removing the solvent, a thicker TBR layer is formed in DBDC, and this thicker TBR layer helps with additional physical adsorption and mechanical entanglement with the external rubber matrix, thus forming a thicker LBR layer. In contrast, only mechanical force is involved in the preparation of MBDC. Although the MQ resin is uniformly dispersed in the phenyl silicone rubber matrix, aggregation occurs during the mixing process. In this case, π-π interactions and hydrogen bonds are limited to the surface of the MQ aggregates, and the phenyl groups and hydrogen bonds within the aggregates cannot interact with phenyl silicone rubber, resulting in a significantly thinner adhesive rubber layer. In DBDC, the higher content of bound rubber increases the interfacial regions within the composite material. Under external force, the rubber molecules in these interfacial regions undergo non-linear deformation, enhancing energy dissipation and improving the complex damping performance.

[0066] Example 6

[0067] Dissolve 100 parts by weight of phenyl silicone rubber (phenyl content is 20 mol%) and 20 parts by weight of MQ resin (0.8M / Q) in dichloromethane, stir and mix at room temperature for 24 hours, and then use an oven to remove the solvent dichloromethane; add the above mixture and 40 parts by weight of fumed silica into a kneader, fully mix at room temperature, then pass through a two-roll mill thinly for 5 minutes, and let stand for 24 hours; finally, add 1 part by weight of bis(2,4) at 25 °C using a two-roll mill to obtain a rubber compound. Transfer the rubber compound to a metal mold, use a vacuum flat vulcanizer to vacuum vulcanize at 110 °C and 10 MPa for 10 minutes, and then secondary vulcanize in a forced-air oven at 180 °C for 4 hours to obtain a wide-temperature-range high-damping silicone rubber.

[0068] Example 7

[0069] Dissolve 100 parts by weight of phenyl silicone rubber (phenyl content is 40 mol%) and 40 parts by weight of MQ resin (0.8M / Q) in dichloromethane, stir and mix at room temperature for 24 hours, and then use an oven to remove the solvent dichloromethane; add the above mixture and 60 parts by weight of fumed silica into a kneader, fully mix at room temperature, then pass through a two-roll mill thinly for 5 minutes, and let stand for 24 hours; finally, add 3 parts by weight of bis(2,4) at 25 °C using a two-roll mill to obtain a rubber compound. Transfer the rubber compound to a metal mold, use a vacuum flat vulcanizer to vacuum vulcanize at 110 °C and 10 MPa for 10 minutes, and then secondary vulcanize in a forced-air oven at 180 °C for 4 hours to obtain a wide-temperature-range high-damping silicone rubber.

[0070] Example 8

[0071] Dissolve 100 parts by weight of phenyl silicone rubber (phenyl content is 30 mol%) and 30 parts by weight of MQ resin (0.8M / Q) in dichloromethane, stir and mix at room temperature for 24 hours, and then use an oven to remove the solvent dichloromethane; add the above mixture and 50 parts by weight of fumed silica into a kneader, fully mix at room temperature, then pass through a two-roll mill thinly for 5 minutes, and let stand for 24 hours; finally, add 2 parts by weight of bis(2,4) at 25 °C using a two-roll mill to obtain a rubber compound. Transfer the rubber compound to a metal mold, use a vacuum flat vulcanizer to vacuum vulcanize at 120 °C and 15 MPa for 5 minutes, and then secondary vulcanize in a forced-air oven at 170 °C for 3 hours to obtain a wide-temperature-range high-damping silicone rubber.

[0072] Example 9

[0073] 100 parts by weight of phenyl silicone rubber (phenyl content is 30 mol%) and 30 parts by weight of MQ resin (0.8 M / Q) are dissolved in dichloromethane, stirred and mixed at room temperature for 24 hours, and then the solvent dichloromethane is removed using an oven; the above mixture and 50 parts by weight of fumed silica are added to a Banbury mixer, fully mixed at room temperature, passed thinly through a two-roll mill for 5 minutes, and left standing for 24 hours; finally, 2 parts by weight of bis(2,4) is added using a two-roll mill at 25°C to obtain a rubber compound. The rubber compound is transferred to a metal mold and vacuum vulcanized at 100°C and 5 MPa for 15 minutes using a vacuum flat vulcanizer, and then post-cured in a forced-air oven at 190°C for 5 hours to obtain a wide-temperature-range high-damping silicone rubber.

[0074] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for preparing a wide temperature range damping silicone rubber by dissolving and blending, characterized in that: The following steps are involved: The phenyl silicone rubber and the MQ resin are dissolved in a solvent, stirred and mixed, and then the solvent is removed, mixed with a reinforcing filler, and then allowed to stand, and then a vulcanizing agent is added and mixed, and the obtained mixture is vulcanized to obtain a wide temperature range damping silicone rubber; The molar ratio of M / Q of the MQ resin is 0.5 to 0.9, and the structure of the M unit is , wherein R1, R2, and R3 are independently selected from one of an alkyl group and an aryl group, and at least one of R1, R2, and R3 is an aryl group; The mass ratio of the MQ resin to the silicone rubber is (0.2-0.4):

1.

2. The method according to claim 1, characterized in that The alkyl group is an alkyl group having 1 to 6 carbon atoms, and the aryl group is a phenyl group or a biphenyl group.

3. The method according to claim 1, characterized in that The phenyl silicone rubber includes monophenyl silicone rubber, and the phenyl content of the phenyl silicone rubber is 20-40 mol%.

4. The method according to claim 1, characterized in that The reinforcing filler includes fumed silica, the vulcanizing agent includes di-2,4, and the mass ratio of the reinforcing filler, the vulcanizing agent and the silicone rubber is (0.4-0.6):(0.01-0.03):

1.

5. The method according to claim 1, characterized in that The solvent includes dichloromethane.

6. The method according to claim 1, characterized in that Dissolve silicone rubber and MQ resin in a solvent, stir and mix at room temperature for 12 to 36 hours; after mixing with reinforcing fillers, let stand at room temperature for 12 to 36 hours.

7. The method according to claim 1, characterized in that Vulcanization includes primary vulcanization and secondary vulcanization; the temperature of primary vulcanization is 100~120℃, the pressure is 5~15 MPa, and the time is 5~15 min; the temperature of secondary vulcanization is 170~190℃, and the time is 3~5 h.

8. A wide temperature range damping silicone rubber, characterized in that: Obtained by the method according to any one of claims 1 to 6.

9. Use of the wide temperature range damping silicone rubber according to claim 8 in the preparation of damping materials and / or damping devices.

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