Single-component dealcoholized organic silicon pouring sealant and preparation method thereof

Abstract

The invention relates to the technical field of pouring sealants, in particular to a single-component dealcoholization type organic silicon pouring sealant and a preparation method thereof.The pouring sealant is prepared from, by weight, 100 parts of polyalkoxy-terminated polydimethylsiloxane, 0.5-8 parts of a catalyst, 0.5-15 parts of a cross-linking agent, 5-20 parts of filler and 0.01-1 part of a fluorescent whitening agent, and the single-component dealcoholization type organic silicon pouring sealant is prepared from, by weight, 100 parts of polyalkoxy-terminated polydimethylsiloxane, 0.5-8 parts of a catalyst, 0.5-15 parts of a cross-linking agent, 5-20 parts of filler and 0.01-1 part of a fluorescent whitening agent. The polyalkoxy-terminated polydimethylsiloxane is adopted as a base material and is matched with other components, so that the obtained pouring sealant has good transparency, tensile property and adhesive property, the viscosity peak phenomenon of the product is effectively reduced, the ageing resistance and storage stability of the product are improved, and meanwhile, the pouring sealant is convenient to use, environment-friendly and safe.

Description

Technical Field

[0001] The invention relates to the technical field of potting adhesives, and in particular to a single-component dealcoholized organosilicon potting adhesive and a preparation method thereof. Background Art

[0002] Potting compound is an adhesive used to seal or fix electronic components. It is poured into the interior of electronic components in liquid form. After curing, it plays a role in bonding, sealing and protecting electronic components, reducing the invasion of external force, moisture, dust and corrosive substances into electronic components, and extending the service life. It has been widely used in electronic products, LED lighting, communication equipment and automotive electronics.

[0003] At present, silicone potting glue has become a research hotspot in the field of potting glue technology due to its excellent comprehensive performance and simple molding process. Room temperature curing silicone potting glue (RTV) is divided into two systems: addition type and condensation type according to different vulcanization mechanisms. When the addition type silicone potting glue is cured, no small molecule by-products are generated, and the curing shrinkage rate is extremely small, but it is prone to catalyst poisoning problems, which makes the glue unable to cure normally. Condensation type RTV spontaneously absorbs moisture from the air, removes small molecule by-products for cross-linking and curing, but the reaction speed is slow, and a certain degree of curing shrinkage is caused when the small molecule by-products are removed; according to the different small molecule by-products generated, it can be divided into dealcoholization type, deketoxime type, dehydrogenation type, deacidification type, etc. In addition, according to different market packaging methods, it is divided into two forms of use: two-component and single-component. Two-component potting glue products are the most common, but because components A and B need to be mixed in a certain proportion before use, operation and construction are inconvenient. Single-component potting glue does not need to be mixed and can be directly poured into electronic components by equipment or manually, and then cured and cross-linked to form an elastomer.

[0004] The low molecular alcohol released by the single-component dealcoholization RTV has the characteristics of low odor, easy volatility, and non-corrosiveness, and has broad application prospects. Traditional dealcoholization RTV generally uses α, ω-dihydroxy polydimethylsiloxane (107 silicone rubber) as the base polymer, which is prone to the phenomenon of "viscosity peak" during the production process of the rubber, and will also affect the use and storage of the rubber. For example, patent CN114479755A discloses a condensation waterproof potting glue, which solves the problem of poor waterproof and moisture-proof performance of the potting glue. It uses double-terminal hydroxyl polydisiloxane as the base material, which has low volatility. The potting glue obtained after mixing with other raw materials has a strong hydrophobic type. However, the initial curing time of this product is 1-3h, and the final tensile strength is only 1.5-3kgf / cm2. In addition, defoamers and acetylene alcohol inhibitors are added to the system. The use of defoamers may reduce the adhesion of the rubber, thereby causing degumming; adding too much acetylene alcohol inhibitors during the volatilization process is easy to increase the shrinkage rate of the product, thereby affecting the surface flatness of the product.

[0005] In general, components are assembled, and the potting glue used is often transparent or translucent, that is, if a component fails during use, the fault point can be directly observed to facilitate later maintenance. However, the transparency and physical and mechanical properties of the product may be mutually contradictory. The potting glue with good transparency sacrifices physical and mechanical properties to a certain extent, such as slow curing speed, low elongation, poor bonding performance, etc. For example, patent CN116376511A provides a transparent deketoxime silicone sealant and preparation method, pointing out that when hydrophilic white carbon black is used as a reinforcing agent and thixotropic agent, the appearance of the produced glue is actually translucent, especially after long-term storage, its transparency decreases more significantly. Based on this, the invention proposes to graft silica with alkaline amino acids to change the surface properties of silica to obtain modified silica, so that the aggregation tendency of silica before the glue is cured is weakened, the transparency after curing is improved, and the transmittance decreases after storage for 30 days. However, after the silica is modified with alkaline amino acids, the tensile strength and elongation at break of the sealant are also weakened.

[0006] Therefore, how to provide a potting adhesive that is simple to operate, safe and environmentally friendly, has a fast curing speed and high light transmittance is the research direction that technicians in this field are committed to. Summary of the invention

[0007] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a single-component dealcoholized organic silicon potting adhesive.

[0008] To achieve the above purpose, the technical solution adopted by the present invention is: a one-component dealcoholized silicone potting adhesive, wherein the raw materials include the following components in parts by weight: 100 parts of polyalkoxy-terminated polydimethylsiloxane, 0.5-8 parts of catalyst, 0.5-15 parts of cross-linking agent, 5-20 parts of filler and 0.01-1 parts of fluorescent brightener.

[0009] As a specific implementation manner, the base material of the polyalkoxy-terminated polydimethylsiloxane is dimethoxy-terminated polydimethylsiloxane with a viscosity of 5000-80000 mPa·s at 25°C.

[0010] As a specific implementation manner, the dimethoxy-terminated polydimethylsiloxane adopts one or more of the brands O-FT800, O-F5000, O-F20000, O-F30000, and O-F80000 produced by Orange Sky New Materials (Guangzhou) Co., Ltd.

[0011] As a specific implementation, the catalyst uses an organic titanium catalyst; the crosslinking agent uses a silane crosslinking agent; the filler uses one or more of fumed silica, alumina, aluminum hydroxide, and calcium carbonate; and the fluorescent whitening agent uses a benzoxazole fluorescent whitening agent.

[0012] As a specific implementation manner, the catalyst uses the titanate chelate TYZOR-9000 produced by India Dovkat Chemicals Co., Ltd.

[0013] As a specific implementation, the filler is hydrophobic fumed silica, and the hydrophobic fumed silica is selected from at least one of Degussa R812S, Wacker H2000, and SD-2002P, SD-2006N, and SD-3001PH produced by Hangzhou Yingxing New Materials Co., Ltd.

[0014] As a specific implementation manner, the cross-linking agent is methyltrimethoxysilane.

[0015] As a specific implementation, the fluorescent whitening agent is 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene.

[0016] Another object of the present invention is to provide a method for preparing the above-mentioned one-component dealcoholized organosilicon potting adhesive, comprising the following steps:

[0017] Step 1, putting polyalkoxy-terminated polydimethylsiloxane and filler into a reaction kettle, stirring at a speed of 60 r / min, roughly mixing until the filler does not fly into powder, and then increasing the speed to 400 r / min and stirring until the mixture is uniformly mixed;

[0018] Step 2, add a crosslinking agent and a fluorescent whitening agent into the reaction kettle, evacuate to below -0.095 MPa, stir at a speed of 400 r / min, and stir for 30-40 min;

[0019] Step 3, adding a catalyst into the reaction kettle, and continuing stirring under a vacuum state below -0.095 MPa for 30-40 minutes to obtain the desired single-component dealcoholization type silicone potting adhesive.

[0020] As a specific implementation manner, during the preparation process, the real-time temperature in the reactor does not exceed 35°C.

[0021] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0022] 1) The present invention provides a one-component dealcoholized organosilicon potting adhesive, which adopts polyalkoxy-terminated polydimethylsiloxane as a base material and is matched with other components to make the obtained potting adhesive have good light transmittance, tensile properties and adhesive properties, effectively reduce the viscosity peak phenomenon of the product, and improve the aging resistance and storage stability of the product;

[0023] 2) The present invention provides a one-component dealcoholized silicone potting adhesive, which is easy to construct and does not require heating for curing. The adhesive can be cured by absorbing moisture in the air. The product is volatile and will not cause corrosive damage to electronic components, which is more environmentally friendly and safe.

[0024] 3) Compared with the prior art, the potting glue and its preparation method provided by the present invention have the advantages of low production cost and simple preparation. When used in the fields of electronic components, electronic modules, etc., it has good flow and filling properties, the product is transparent, the fault point can be directly observed, and it is convenient for later maintenance. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is further described below in conjunction with specific embodiments.

[0026] The following provides a one-component dealcoholized silicone potting adhesive. The raw materials include the following components in parts by weight: 100 parts of polyalkoxy-terminated polydimethylsiloxane, 0.5-8 parts of catalyst, 0.5-15 parts of cross-linking agent, 5-20 parts of filler and 0.01-1 parts of fluorescent brightener.

[0027] The base material of the polyalkoxy-terminated polydimethylsiloxane is dimethoxy-terminated polydimethylsiloxane with a viscosity between 5000 and 85000 mPa·s at 25°C.

[0028] In the following embodiments:

[0029] Polydimethylsiloxane O-FT800, O-F5000, O-F20000, O-F30000, and O-F80000 were all purchased from Chengtian New Materials (Guangzhou) Co., Ltd.

[0030] Among them, the viscosity of O-FT800 is 75000~85000mPa·s; the viscosity of O-F5000 is 5000mPa·s; the viscosity of O-F20000 is 20000mPa·s; the viscosity of O-F30000 is 30000mPa·s; and the viscosity of O-F80000 is 80000mPa·s.

[0031] The catalyst titanium complex M-T210 was purchased from Chengtian New Materials (Guangzhou) Co., Ltd.; the titanate chelate TYZOR-9000 was purchased from Dovkat Chemicals Ltd., India.

[0032] Methyltrimethoxysilane (MTMS, CAS: 1185-55-3) was used as the crosslinking agent.

[0033] The filler is a hydrophobic fumed silica with different specific surface areas, such as R812S, H2000, and at least one of SD-2002P, SD-2006N, and SD-3001PH produced by Hangzhou Yingxing.

[0034] Among them, hydrophobic fumed silica R812S was purchased from Degussa Chemical, and its tap density is 60g / L; hydrophobic fumed silica H2000 was purchased from Wacker Chemical, and its tap density is 200g / L; the tap density of SD-2002P is 300g / L; the tap density of SD-2006N is 50g / L; and the tap density of SD-3001PH is 60g / L.

[0035] Titanate chelate TYZOR-9000 is produced by Dorf Ketal.

[0036] The fluorescent brightener used is 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene (CAS: 7128-64-5).

[0037] Example 1

[0038] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components in parts by weight: 35 parts of dimethoxy-terminated polydimethylsiloxane O-F80000, 65 parts of dimethoxy-terminated polydimethylsiloxane O-F5000, 2.5 parts of hydrophobic fumed silica SD-2002P, 7.5 parts of hydrophobic fumed silica SD-3001PH, 4 parts of methyltrimethoxysilane MTMS, 1.5 parts of titanate chelate TYZOR-9000, and 0.02 parts of fluorescent whitening agent OB.

[0039] The preparation process of the one-component dealcoholized silicone potting adhesive in this example is as follows:

[0040] Step 1, roughly mix the hydrophobic fumed silica SD-2002P and the hydrophobic fumed silica SD-3001PH into the dimethoxy-terminated polydimethylsiloxane O-F80000 and the dimethoxy-terminated polydimethylsiloxane O-F5000, stir at a speed of 60 r / min until the fumed silica does not fly powder, increase the speed to 400 r / min, and stir for 30 minutes until the mixture is evenly mixed;

[0041] 2) Add methyltrimethoxysilane MTMS and fluorescent brightener OB, evacuate to below -0.095 MPa, and stir at 400 r / min for 30 min until the mixture is uniformly mixed;

[0042] 3) Finally, add the titanate chelate TYZOR-9000, evacuate to below -0.095MPa, stir at high speed for 30 minutes until the mixture is evenly mixed, and extrude the material. (At the same time, pay attention to the stirring state of the rubber material. If the "viscosity peak" phenomenon occurs, the stirring time should be appropriately extended.)

[0043] Example 2

[0044] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components in parts by weight: 35 parts of dimethoxy-terminated polydimethylsiloxane O-F20000, 65 parts of dimethoxy-terminated polydimethylsiloxane O-F5000, 10 parts of hydrophobic fumed silica R812S, 4 parts of methyltrimethoxysilane MTMS, 1.5 parts of titanate chelate TYZOR-9000, and 0.02 parts of fluorescent brightener OB.

[0045] The preparation method of the one-component dealcoholized silicone potting adhesive in this example is the same as that in Example 1.

[0046] Example 3

[0047] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components in parts by weight: 35 parts of dimethoxy-terminated polydimethylsiloxane O-F20000, 65 parts of dimethoxy-terminated polydimethylsiloxane O-F5000, 2 parts of hydrophobic fumed silica H2000, 8 parts of hydrophobic fumed silica R812S, 4 parts of methyltrimethoxysilane MTMS, 1.5 parts of titanate chelate TYZOR-9000, and 0.02 parts of fluorescent whitening agent OB.

[0048] The preparation method of the one-component dealcoholized silicone potting adhesive in this example is the same as that in Example 1.

[0049] Example 4

[0050] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components in parts by weight: 35 parts of dimethoxy-terminated polydimethylsiloxane O-F20000, 65 parts of dimethoxy-terminated polydimethylsiloxane O-F5000, 2 parts of hydrophobic fumed silica H2000, 8 parts of hydrophobic fumed silica R812S, 4 parts of methyltrimethoxysilane MTMS, 1.5 parts of titanate chelate TYZOR-9000, and 0.02 parts of fluorescent whitening agent OB.

[0051] The preparation method of the one-component dealcoholized silicone potting adhesive in this example is the same as that in Example 1, except that after the titanate chelate TYZOR-9000 is added, the stirring time is extended to 60 minutes.

[0052] Example 5

[0053] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components in parts by weight: 80 parts of dimethoxy-terminated polydimethylsiloxane O-F30000, 20 parts of dimethoxy-terminated polydimethylsiloxane O-FT800, 2 parts of hydrophobic fumed silica SD-2002P, 8 parts of hydrophobic fumed silica SD-2006N, 4 parts of methyltrimethoxysilane MTMS, 1.5 parts of titanate chelate TYZOR-9000, and 0.02 parts of fluorescent whitening agent OB.

[0054] The preparation method of the one-component dealcoholized silicone potting adhesive in this example is the same as that in Example 1.

[0055] Example 6

[0056] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components in parts by weight: 35 parts of dimethoxy-terminated polydimethylsiloxane O-F20000, 65 parts of dimethoxy-terminated polydimethylsiloxane O-F5000, 2 parts of hydrophobic fumed silica SD-2002P, 8 parts of hydrophobic fumed silica R812S, 4 parts of methyltrimethoxysilane MTMS, 1.5 parts of titanate chelate TYZOR-9000, and 0.02 parts of fluorescent brightener OB.

[0057] The preparation method of the one-component dealcoholized silicone potting adhesive in this example is the same as that in Example 1.

[0058] Comparative Example 1

[0059] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components by weight: 35 parts of dimethoxy-terminated polydimethylsiloxane O-F20000, 65 parts of dimethoxy-terminated polydimethylsiloxane O-F5000, 2 parts of hydrophobic fumed silica H2000, 8 parts of hydrophobic fumed silica R812S, 4 parts of methyltrimethoxysilane MTMS, 1.5 parts of titanium complex M-T210, and 0.02 parts of fluorescent brightener OB;

[0060] Among them, titanium complex M-T210 was purchased from Chengtian New Materials;

[0061] The preparation method of the one-component dealcoholized silicone potting adhesive in this example is the same as that in Example 1.

[0062] Comparative Example 2

[0063] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components by weight: 35 parts of dimethoxy-terminated polydimethylsiloxane O-F20000, 65 parts of dimethoxy-terminated polydimethylsiloxane O-F5000, 2 parts of hydrophobic fumed silica H2000, 8 parts of hydrophobic fumed silica R812S, 4 parts of methyltrimethoxysilane MTMS, 8 parts of titanate chelate TYZOR-9000, and 0.02 parts of fluorescent brightener OB;

[0064] The preparation method of the one-component dealcoholized silicone potting adhesive in this example is the same as that in Example 1.

[0065] Comparative Example 3

[0066] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components by weight: 35 parts of dimethoxy-terminated polydimethylsiloxane O-F20000, 65 parts of dimethoxy-terminated polydimethylsiloxane O-F5000, 4 parts of methyltrimethoxysilane MTMS, 1.5 parts of titanate chelate TYZOR-9000, and 0.02 parts of fluorescent brightener OB;

[0067] The preparation method of the single-component dealcoholized organic silicon potting adhesive in this example is similar to that in Example 1, omitting the step of uniformly mixing the gas and silicon.

[0068] Comparative Example 4

[0069] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components by weight: 100 parts of dimethoxy-terminated polydimethylsiloxane O-F20000, 2 parts of hydrophobic fumed silica H2000, 8 parts of hydrophobic fumed silica R812S, 4 parts of methyltrimethoxysilane MTMS, 1.5 parts of titanium complex TYZOR-9000, and 0.02 parts of fluorescent brightener OB;

[0070] The preparation method of the one-component dealcoholized silicone potting adhesive in this example is the same as that in Example 1.

[0071] Comparative Example 5

[0072] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components by weight: 100 parts of dimethoxy-terminated polydimethylsiloxane O-F5000, 2 parts of hydrophobic fumed silica H2000, 8 parts of hydrophobic fumed silica R812S, 4 parts of methyltrimethoxysilane MTMS, 1.5 parts of titanate chelate TYZOR-9000, and 0.02 parts of fluorescent brightener OB;

[0073] The preparation method of the one-component dealcoholized silicone potting adhesive in this example is the same as that in Example 1.

[0074] Comparative Example 6

[0075] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components by weight: 35 parts of dimethoxy-terminated polydimethylsiloxane O-F20000, 65 parts of dimethoxy-terminated polydimethylsiloxane O-F5000, 10 parts of hydrophobic fumed silica H2000, 4 parts of methyltrimethoxysilane MTMS, 1.5 parts of titanate chelate TYZOR-9000, and 0.02 parts of fluorescent brightener OB;

[0076] The preparation method of the one-component dealcoholized silicone potting adhesive in this example is the same as that in Example 1.

[0077] Comparative Example 7

[0078] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components in parts by weight: 100 parts of dimethoxy-terminated polydimethylsiloxane O-F30000, 2 parts of hydrophobic fumed silica SD-2002P, 8 parts of hydrophobic fumed silica SD-2006N, 4 parts of methyltrimethoxysilane MTMS, 1.5 parts of titanate chelate TYZOR-9000, and 0.02 parts of fluorescent whitening agent OB.

[0079] The preparation method of the one-component dealcoholized silicone potting adhesive in this example is the same as that in Example 1.

[0080] Comparative Example 8

[0081] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components in parts by weight: 100 parts of dimethoxy-terminated polydimethylsiloxane O-F80000, 2.5 parts of hydrophobic fumed silica SD-2002P, 7.5 parts of hydrophobic fumed silica SD-3001PH, 4 parts of methyltrimethoxysilane MTMS, 1.5 parts of titanate chelate TYZOR-9000, and 0.02 parts of fluorescent whitening agent OB.

[0082] The preparation method of the one-component dealcoholized silicone potting adhesive in this example is the same as that in Example 1.

[0083] Comparative Example 9

[0084] This example provides a one-component dealcoholized silicone potting adhesive, which includes the following components in parts by weight: 35 parts of dimethoxy-terminated polydimethylsiloxane O-F20000, 65 parts of dimethoxy-terminated polydimethylsiloxane O-F5000, 2 parts of hydrophobic fumed silica H2000, 8 parts of hydrophobic fumed silica R812S, 4 parts of methyltrimethoxysilane MTMS, 0.4 parts of titanate chelate TYZOR-9000, and 0.02 parts of fluorescent whitening agent OB.

[0085] The preparation method of the one-component dealcoholized silicone potting adhesive in this example is the same as that in Example 1.

[0086] The silicone potting adhesives obtained in the above examples and comparative examples were tested for the following items:

[0087] 1) Surface drying test: The surface drying time (room temperature) of the obtained silicone potting adhesive is tested according to GB / T 13477.5-2002;

[0088] 2) Viscosity test: The viscosity of the obtained silicone potting compound was tested at 25°C and a constant shear rate using a rotational rheometer, with a 25 mm flat rotor, 1 mm spacing, and a shear rate of 2 s -1 , test time 5min;

[0089] 3) Tensile strength and elongation at break: The tensile strength and elongation at break of the obtained silicone potting compound were tested using the national standard GB / T 528-2009 (room temperature);

[0090] 4) Optical test: Use a spectrophotometer (room temperature) to test the transmittance of the potting glue film in the visible light wavelength range of 190-800nm, and record the L*, a*, and b* values;

[0091] 5) Hardness: The Shore A hardness of the obtained silicone potting compound was tested using the national standard GB / T 531.1-2008 (room temperature);

[0092] 6) Aging test: The cured film was placed in an aging box at a temperature of 85°C and a humidity of 85% for accelerated aging for 168 hours and 1000 hours, then taken out and tested after cooling to room temperature.

[0093] The test results are shown in Table 1.

[0094] Table 1

[0095]

[0096]

[0097] The samples prepared in Examples 1-4 and Comparative Examples 1 and 2 were aged, and the test results are as follows:

[0098] Table 2

[0099]

[0100] It can be seen from Tables 1 and 2 that the silicone potting adhesive prepared by the preparation method of the present invention has good comprehensive performance, and after accelerated aging, the performance declines reasonably, indicating that the product has good stability and has a wide range of application scenarios.

[0101] From the comparison between Examples 3 and 4, it can be seen that after adding the catalyst, the stirring time is extended, and the hydrogen bonds are broken by mechanical force in a vacuum environment to make the colloid pass through a viscosity peak, which not only reduces the viscosity of the entire adhesive system, but also slightly improves the transparency of the potting glue. However, this process also leads to an extension of the production time and increases the overall production cost.

[0102] From the colloidal systems of Example 3 and Comparative Examples 1, 2, and 9, the type and amount of the catalyst determine the surface drying and curing speed of the potting glue. The titanium-based catalyst determines that it will have different degrees of yellowness according to the groups around its titanium atoms, which affects the yellow chromaticity index of the potting glue product and the yellowing problem of subsequent aging; because the potting glue is cured from the outside to the inside, when the amount of the catalyst is too large and the surface of the potting glue is cured too quickly, moisture can no longer enter the interior of the glue system, resulting in insufficient curing depth of the potting glue, inability to achieve potting, and low elongation at break; similarly, when the amount of the catalyst is too small, the surface drying time is too long or even impossible to dry, and the potting glue cannot achieve its use value.

[0103] Comparative Example 3 Compared with Example 3, no filler is added in Comparative Example 3, and the viscosity of the system is very small, which leads to a greatly prolonged surface drying time, while the tensile strength and elongation at break are greatly reduced.

[0104] Compared with Example 3 and Comparative Example 4, Comparative Example 4 simply uses methoxy-terminated polydimethylsiloxane O-F20000 as the base polymer, so that its surface drying time is extended compared with Example 3, and the viscosity is greatly increased. At the same time, the tensile strength and elongation at break are increased, and the transparency is slightly reduced; Compared with Example 3 and Comparative Example 5, Comparative Example 5 solely uses methoxy-terminated polydimethylsiloxane O-F5000 as the base polymer, and the surface drying time is extended, the viscosity is reduced, and the tensile strength and elongation at break are also greatly reduced.

[0105] Comparing the colloid systems of Example 5 and Comparative Example 7, it can be seen that when the dimethoxy-terminated polydimethylsiloxane O-F30000 is used alone as the base polymer, the surface drying time is too long, the viscosity is reduced, the transparency of the product is improved, but the tensile strength and elongation at break are greatly reduced.

[0106] Compared with Example 1, Comparative Example 8 uses dimethoxy-terminated polydimethylsiloxane O-F80000 as the base polymer alone. Its surface drying time is prolonged, the viscosity is too high, the tensile strength is increased, but the elongation at break is greatly reduced. At the same time, the transparency and yellowing value of the product are greatly affected.

[0107] By comparing Examples 1 and 3 with Comparative Examples 4, 5, 7 and 8, it can be seen that the various properties of the colloid system involving a single base polymer or reinforcing filler cannot reach the optimal level. Only by producing with a reasonable ratio can the comprehensive performance of the potting glue be the most excellent and stable.

[0108] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A one-component dealcoholized silicone potting adhesive, characterized in that: The raw materials include the following components in parts by weight: 100 parts of polyalkoxy-terminated polydimethylsiloxane, 0.5-8 parts of catalyst, 0.5-15 parts of crosslinking agent, 5-20 parts of filler and 0.01-1 parts of fluorescent brightener.

2. A one-component dealcoholized silicone potting adhesive according to claim 1, characterized in that: The base material of the polyalkoxy-terminated polydimethylsiloxane is dimethoxy-terminated polydimethylsiloxane with a viscosity between 5000 and 80000 mPa·s at 25°C.

3. A one-component dealcoholized silicone potting adhesive according to claim 2, characterized in that: The dimethoxy-terminated polydimethylsiloxane is one or more of the brands O-FT800, O-F5000, O-F20000, O-F30000, and O-F80000 produced by Orange Sky New Materials (Guangzhou) Co., Ltd.

4. The one-component dealcoholized silicone potting adhesive according to claim 1, characterized in that: The catalyst adopts an organic titanium catalyst; the crosslinking agent adopts a silane crosslinking agent; the filler adopts one or more of fumed silica, alumina, aluminum hydroxide, and calcium carbonate; and the fluorescent brightener adopts a benzoxazole fluorescent brightener.

5. The one-component dealcoholized organosilicon potting adhesive according to claim 4, characterized in that: The catalyst used is the titanate chelate TYZOR-9000 produced by India Dovkat Chemical Co., Ltd.

6. The one-component dealcoholized organic silicone potting adhesive according to claim 4, characterized in that: The filler is hydrophobic fumed silica, and the hydrophobic fumed silica is selected from at least one of Degussa R812S, Wacker H2000, and SD-2002P, SD-2006N, and SD-3001PH produced by Hangzhou Yingxing New Materials Co., Ltd.

7. The one-component dealcoholized organosilicon potting adhesive according to claim 4, characterized in that: The crosslinking agent used was methyltrimethoxysilane.

8. The one-component dealcoholized organosilicon potting adhesive according to claim 4, characterized in that: The fluorescent brightener adopts 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene.

9. A method for preparing a one-component dealcoholized organosilicon potting adhesive as claimed in any one of claims 1 to 8, characterized in that: The following steps are involved: Step 1, putting polyalkoxy-terminated polydimethylsiloxane and filler into a reaction kettle, stirring at a speed of 60 r / min, roughly mixing until the filler does not fly into powder, and then increasing the speed to 400 r / min and stirring until the mixture is uniformly mixed; Step 2, add a crosslinking agent and a fluorescent whitening agent into the reaction kettle, evacuate to below -0.095 MPa, stir at a speed of 400 r / min, and stir for 30-40 min; Step 3, adding a catalyst into the reaction kettle, and continuing stirring under a vacuum state below -0.095 MPa for 30-40 minutes to obtain the desired single-component dealcoholization type silicone potting adhesive.

10. The method for preparing a one-component dealcoholization type silicone potting adhesive according to claim 9, characterized in that: During the preparation process, the real-time temperature in the reactor does not exceed 35°C.

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