A moisture vapor dual-cured modified polysiloxane and a method for preparing the same

Abstract

The application discloses a light-humidity dual-cured modified polysiloxane and a preparation method thereof, and belongs to the technical field of organic silicon polymer materials. First, dimethylsiloxane mixed ring, phenyl methyl dimethoxysilane coupling agent and 1,3-divinyl-1,1,3,3-tetramethyldisiloxane are reacted under the condition of an alkaline catalyst to obtain a first intermediate product; the first intermediate product is reacted with tetramethylcyclotetrasiloxane under the action of a first catalyst to obtain a second intermediate product; and the second intermediate product is reacted with 4-vinyl epoxycyclohexane and vinyltrimethoxysilane under the action of a second catalyst to obtain the light-humidity dual-cured modified polysiloxane. The modified polysiloxane can be quickly surface-dried and shaped through ultraviolet irradiation, and then the depth curing of shadow parts and thick coatings can be completed through humidity curing, so that the problem that a single light-cured system is difficult to completely cure is effectively solved, and the curing efficiency is high and the completeness is good.

Description

Technical Field

[0001] This application relates to the field of organosilicon polymer materials technology, specifically to a modified polysiloxane that undergoes photo-moisture dual curing and its preparation method. Background Technology

[0002] Ultraviolet (UV) curing technology has been widely used in coatings, inks, adhesives, and electronic packaging due to its advantages such as fast curing speed, low energy consumption, and no solvent emissions. However, UV curing technology has an inherent limitation: it can only effectively cure transparent substrates or areas directly exposed to UV light. For shaded areas of the substrate, inner surfaces of complex structures, or areas covered by opaque substrates, UV light cannot penetrate to reach them, resulting in incomplete curing of coatings or adhesives in these areas, which seriously affects the overall performance and reliability of the product.

[0003] To address these issues, researchers have developed a dual UV / moisture curing system. This type of system typically contains both carbon unsaturated bonds and silane groups. The carbon unsaturated bonds undergo free radical polymerization under UV irradiation for photocuring, while the silane groups undergo hydrolysis and condensation with moisture in the air after irradiation, achieving moisture-assisted curing. Both UV and moisture curing improve the thermodynamic properties of this system. However, the curing speed and final degree of curing in existing free radical UV / moisture dual curing systems are still not ideal, and their thermodynamic properties, such as volume shrinkage, hardness, tensile strength, and thermal stability, are insufficient to meet the stringent requirements of high-end applications in electronic packaging and aerospace coatings.

[0004] In the field of polysiloxane modification research, researchers have attempted to improve the heat resistance and mechanical strength of materials by introducing rigid groups such as phenyl groups, and have also tried to impart additional curing ability and bonding properties to materials by introducing epoxy groups. However, existing studies mostly introduce phenyl and epoxy groups independently into polysiloxane molecules, or simply mix them, failing to fully utilize the synergistic enhancement potential of the two functional groups at the molecular topology level. Summary of the Invention

[0005] The purpose of this application is to provide a modified polysiloxane material that can be both photocured and moisture-cured, and has excellent thermal stability and mechanical properties.

[0006] To achieve the above objectives, the technical solution adopted in this application is as follows: A modified polysiloxane with photo- and moisture-curing properties is provided, the structural formula of which is: , where R is either epoxycyclohexyl or trimethoxysilyl, and the same structure contains both R groups, 1≤m≤20, 99≤n≤999.

[0007] This application also provides a method for preparing a photo- and moisture-cured modified polysiloxane, comprising the following steps: S1: reacting a mixed cyclic form of dimethylsiloxane, a phenylmethyldimethoxysilane coupling agent, and 1,3-divinyl-1,1,3,3-tetramethyldisiloxane under alkaline catalytic conditions to obtain a first intermediate product; S2: reacting the first intermediate product with tetramethylcyclotetrasiloxane under the action of a first catalyst to obtain a second intermediate product; S3: reacting the second intermediate product with 4-vinylepoxycyclohexane and vinyltrimethoxysilane under the action of a second catalyst to obtain the photo- and moisture-cured modified polysiloxane. The structural formula of the first intermediate product is: Where 1≤m≤20, 99≤n≤999; The structural formula of the second intermediate product is: , where 1≤m≤20, 99≤n≤999.

[0008] As a preferred embodiment, the mass ratio of the phenylmethyldimethoxysilane coupling agent to the dimethylsiloxane mixed ring is 1:(1~99).

[0009] As another preferred embodiment, the mass ratio of the 1,3-divinyl-1,1,3,3-tetramethyldisiloxane to the dimethylsiloxane mixed ring is 1:(1~999).

[0010] As another preferred embodiment, the molar ratio of the first intermediate product to the tetramethylcyclotetrasiloxane is (1~5):(2~10).

[0011] As another preferred embodiment, the molar ratio of the second intermediate product to the 4-vinylepoxycyclohexane is (1~5):(2~10).

[0012] As another preferred embodiment, step S1 specifically involves: adding the dimethylsiloxane mixed cyclic compound, the phenylmethyldimethoxysilane coupling agent, and the 1,3-divinyl-1,1,3,3-tetramethyldisiloxane to a reaction vessel under an inert gas atmosphere; adding an alkaline catalyst; heating to 120-180 °C; maintaining the temperature for 6-8 h; and removing low-boiling substances for 2-4 h to obtain the first intermediate product.

[0013] As another preferred embodiment, step S2 specifically involves: adding the first intermediate product, the tetramethylcyclotetrasiloxane, and isopropanol to a reaction vessel under an inert gas atmosphere, adding the first catalyst, and heating to 95-150 °C, maintaining the temperature for 4-6 h until the material system becomes transparent, thereby obtaining the second intermediate product.

[0014] As another preferred embodiment, step S3 specifically involves: adding the second intermediate product and the 4-vinylepoxycyclohexane and vinyltrimethoxysilane to a reaction vessel under an inert gas atmosphere, followed by adding a second catalyst and heating to 95-150 °C, maintaining the temperature for 4-6 h until the material system becomes transparent, and removing low-boiling substances for 2-4 h to obtain the photo-moisture-gas dual-curing modified polysiloxane.

[0015] More preferably, the alkaline catalyst is potassium hydroxide or tetramethylammonium hydroxide, and both the first catalyst and the second catalyst are caster catalysts.

[0016] Compared with the prior art, the beneficial effects of this application are as follows: (1) The modified polysiloxane of this application has dual curing characteristics of light and moisture. It can achieve rapid surface drying and shaping by ultraviolet irradiation, and then complete the deep curing of shadow areas and thick coatings by moisture curing. It effectively solves the problem that a single light curing system is difficult to completely cure. It has high curing efficiency and good fullness. (2) The modified polysiloxane of this application is designed with a molecular structure of phenyl-modified main chain and cyclic siloxane branched graft alicyclic epoxy. Through the synergistic effect of multiple unit structures, it effectively improves the mechanical strength and thermal stability of the material, resulting in better overall performance and expanding more application scenarios. (3) The preparation process of this application is simple and controllable, the reaction conditions are mild and the reaction endpoint is easy to judge. The feed ratio of each raw material is adjustable in a wide range. The component ratio can be flexibly adjusted according to the performance requirements of the target product. Within a wide range of formulations, the modified polysiloxanes obtained can maintain good mechanical properties and thermal stability, and can adapt to the usage requirements of different application scenarios. The production flexibility and process adaptability are strong. Detailed Implementation

[0017] The present application will be further described below with reference to specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0018] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0019] This application provides a modified polysiloxane material that undergoes both light and moisture curing, with the following structural formula: , where R is either epoxycyclohexyl or trimethoxysilyl, and the same structure contains both R groups, 1≤m≤20, 99≤n≤999.

[0020] This application achieves a dual-curing effect of synergistic UV curing and moisture curing by introducing silanoxy groups and epoxycyclohexane into modified polysiloxane materials. Under UV irradiation, the epoxy groups drive the cationic polymerization of the system, achieving rapid curing of the material surface. The silanoxy groups undergo a condensation reaction with water vapor, enabling deep curing of shadow areas that UV light cannot penetrate or the internal areas of thick coatings. This effectively solves the industry pain point that traditional single UV curing technology is difficult to completely cure complex structural parts.

[0021] Meanwhile, moisture curing, as a supplementary curing path to photocuring, can significantly alleviate the oxygen inhibition effect during photocuring, improve the uniformity and integrity of its cured cross-linked network structure, and greatly shorten the time required for complete curing of the material. It has the advantages of high curing efficiency and complete curing.

[0022] This application utilizes structural design to form a spindle-shaped molecular topology. This molecular structure can increase the entanglement and crosslinking density of molecular chains through cyclic branching units, effectively improving the strength and mechanical load-bearing capacity of the material. The introduction of rigid phenyl groups into the main chain of the modified polysiloxane material enhances interchain forces through π-π interactions with molecules, thereby improving the glass transition temperature and thermal decomposition stability of the material.

[0023] The spindle-shaped structure and rigid phenyl groups work synergistically to improve the hardness and mechanical strength of modified polysiloxane materials while retaining their inherent low-temperature flexibility, resulting in modified polysiloxane materials with excellent comprehensive thermodynamic properties through dual photo- and moisture-curing processes.

[0024] This application provides a method for preparing a modified polysiloxane material that undergoes both light and moisture curing, comprising the following steps: S1: The first intermediate product is prepared by reacting dimethylsiloxane mixed cyclic molecule (DMC), phenylmethyldimethoxysilane coupling agent and 1,3-divinyl-1,1,3,3-tetramethyldisiloxane under alkaline catalytic conditions. S2: The first intermediate product is reacted with tetramethylcyclotetrasiloxane under the action of the first catalyst to obtain the second intermediate product; S3: The photo- and moisture-cured modified polysiloxane of this application is prepared by reacting the second intermediate product, 4-vinylepoxycyclohexane and vinyltrimethoxysilane with a second catalyst.

[0025] The general structural formula of the first intermediate product is: , where 1≤m≤20, 99≤n≤999.

[0026] The general structural formula of the second intermediate product is: , where 1≤m≤20, 99≤n≤999.

[0027] This application constructs the main chain backbone of polysiloxane through a dimethylsiloxane mixed ring. Introducing phenyl groups in the S1 ring-opening copolymerization step hinders the free rotation of chain segments, which is beneficial to improving the glass transition temperature and heat resistance of the polymer. In addition, the π electron cloud in the phenyl structure can participate in the energy transfer during the ultraviolet light initiation process, which helps to achieve UV curing.

[0028] 1,3-Divinyl-1,1,3,3-tetramethyldisiloxane, used as a capping agent to introduce vinyl groups, allows for the control of the polymer and molecular weight of the first intermediate by adjusting the feed ratio of the dual-capped and dimethylsiloxane mixed rings, thus providing specific vinyl reaction sites for subsequent grafting. The cyclic structure of tetramethylcyclotetrasiloxane can serve as a rigid node introduced into the molecular chain end, increasing the local crosslinking density and improving thermal stability.

[0029] 4-Vinylepoxycyclohexane and vinyltrimethoxysilane are grafted through a second hydrosilylation process to introduce epoxy groups and siloxy groups, enabling secondary curing under humid conditions. This compensates for the inherent defects of shadow areas that cannot be reached by single UV light or the inability to penetrate thick coatings.

[0030] In some embodiments, the mass ratio of phenylmethyldimethoxysilane coupling agent to dimethylsiloxane mixed rings is 1:(1~99). The mass ratio of 1,3-divinyl-1,1,3,3-tetramethyldisiloxane to dimethylsiloxane mixed rings is 1:(1~999).

[0031] In some embodiments, the molar ratio of the first intermediate to tetramethylcyclotetrasiloxane is (1~5):(2~10).

[0032] In some embodiments, the molar ratio of the second intermediate to 4-vinylepoxycyclohexane is (1~5):(2~10).

[0033] In some embodiments, the molar ratio of the second intermediate to vinyltrimethoxysilane is (1~5):(2~10).

[0034] This application provides a specific method for preparing a modified polysiloxane material that undergoes both light and moisture curing, comprising the following steps: S1: Under an inert gas atmosphere, dimethylsiloxane mixed ring, phenylmethyldimethoxysilane coupling agent and 1,3-divinyl-1,1,3,3-tetramethyldisiloxane are added to the reaction vessel, an alkaline catalyst is added and the temperature is raised to 120~180 ℃, the reaction is maintained at this temperature for 6~8 h, and the first intermediate product is obtained after removing low-boiling substances for 2~4 h. S2: Under an inert gas atmosphere, the first intermediate product, tetramethylcyclotetrasiloxane, and isopropanol are added to the reaction vessel, the first catalyst is added, and the temperature is raised to 95~150 ℃. The reaction is maintained at this temperature for 4~6 h until the material system becomes transparent, thus obtaining the second intermediate product. S3: Under an inert gas atmosphere, the second intermediate product, 4-vinylepoxycyclohexane and vinyltrimethoxysilane are added to the reaction vessel, followed by the addition of the second catalyst and the temperature is raised to 95~150 ℃. The reaction is maintained at this temperature for 4~6 h until the material system is transparent. After removing low-boiling substances for 2~4 h, the modified polysiloxane with photo-moisture dual curing of this application is obtained.

[0035] In some embodiments, the alkaline catalyst may be potassium hydroxide or tetramethylammonium hydroxide.

[0036] In some embodiments, both the first catalyst and the second catalyst are cassette catalysts, and the amount of cassette catalyst used is 1.2~2 ppm.

[0037] This application uses a mixture of dimethylsiloxane rings, phenylmethyldimethoxysilane, and 1,3-divinyl-1,1,3,3-tetramethyldisiloxane as raw materials. A ring-opening polymerization reaction is carried out under the action of an alkaline catalyst to introduce silanoxy groups into the polysiloxane molecular backbone, yielding a first intermediate. Subsequently, the first intermediate is reacted with tetramethylcyclotetrasiloxane under the catalysis of a Castanet catalyst to undergo a hydrosilylation reaction, grafting cyclic siloxane units containing active silane-hydrogen bonds onto the molecular backbone, yielding a second intermediate. The second intermediate retains highly reactive silane-hydrogen functional groups and can serve as a general intermediate for functional modification. Various functional groups can be grafted onto it via subsequent hydrosilylation reactions, providing a new synthetic route for preparing various types of functionalized modified siloxanes.

[0038] Finally, 4-vinylepoxycyclohexane and vinyltrimethoxysilane were grafted onto the second intermediate via a hydrosilylation reaction, ultimately forming a spindle-shaped product structure. This molecular structure possesses both phenyl and cyclohexane functional groups, enabling dual UV-moisture curing while simultaneously achieving a synergistic effect with the rigid phenyl group through its structural state, thus endowing the material with superior thermal stability and mechanical properties.

[0039] Example 1 A modified polysiloxane material with photocuring and moisture curing was prepared according to the following preparation method, by mass parts: S1: Under a nitrogen atmosphere, 1000 parts of dimethylsiloxane mixed cyclic compound, 40 parts of phenylmethyldimethoxysilane coupling agent and 40 parts of 1,3-divinyl-1,1,3,3-tetramethyldisiloxane were added to a reactor. Then, potassium hydroxide catalyst was added and the temperature was raised to 150 °C. The reaction was maintained at this temperature for 8 h. The pressure was then evacuated to 0.02~0.03 MPa to remove low-boiling substances. The pressure was then increased to 0.05~1 MPa and maintained for 4 h to obtain the first intermediate product. S2: Under a nitrogen atmosphere, the first intermediate product mentioned above, 110 parts of tetramethylcyclotetrasiloxane, and 100 parts of isopropanol were added to the reactor. Then, a caster catalyst was added and the temperature was raised to 120 °C. The amount of caster catalyst was about 1.5 ppm. The reaction was maintained at this temperature for about 6 hours until the material system became transparent, thus obtaining the second intermediate product. S3: Under a nitrogen atmosphere, the above-mentioned second intermediate product, 120 parts of 4-vinylepoxycyclohexane, and 70 parts of vinyltrimethoxysilane were added to the reactor. Then, a caster catalyst was added and the temperature was raised to 120 °C. The amount of caster catalyst was about 2 ppm. The reaction was maintained at this temperature for about 6 hours until the material system became transparent. After removing low-boiling substances for 3 hours, the photo-moisture-gas dual-curing modified polysiloxane of this application was obtained.

[0040] Example 2 The phenylmethyldimethoxysilane coupling agent in step S1 was adjusted to 60 parts by mass, while the other preparation steps remained the same as those in Example 1.

[0041] Example 3 The phenylmethyldimethoxysilane coupling agent in step S1 was adjusted to 80 parts by mass, while the other preparation steps remained the same as those in Example 1.

[0042] Example 4 In step S1, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane was adjusted to 20 parts by mass; in step S2, tetramethylcyclotetrasiloxane was adjusted to 60 parts by mass; in step S3, 4-vinylepoxycyclohexane was adjusted to 60 parts by mass; and vinyltrimethoxysilane was adjusted to 30 parts by mass. The other preparation steps were consistent with the preparation steps in Example 1.

[0043] Example 5 In step S1, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane was adjusted to 60 parts by mass; in step S2, tetramethylcyclotetrasiloxane was adjusted to 160 parts by mass; in step S3, 4-vinylepoxycyclohexane was adjusted to 180 parts by mass; and vinyltrimethoxysilane was adjusted to 100 parts by mass. The other preparation steps were consistent with the preparation steps in Example 1.

[0044] Example 6 In step S3, the amount of 4-vinylepoxycyclohexane was adjusted to 80 parts by mass, and the amount of vinyltrimethoxysilane was adjusted to 100 parts by mass. The other preparation steps were the same as those in Example 1.

[0045] Example 7 In step S3, the amount of 4-vinylepoxycyclohexane was adjusted to 150 parts by mass, and the amount of vinyltrimethoxysilane was adjusted to 30 parts by mass. The other preparation steps were the same as those in Example 1.

[0046] Example 8 In step S3, the amount of 4-vinylepoxycyclohexane was adjusted to 180 parts by mass, and the amount of vinyltrimethoxysilane was adjusted to 20 parts by mass. The other preparation steps were the same as those in Example 1.

[0047] Comparative Example 1 In step S1, the phenylmethyldimethoxysilane coupling agent was replaced with octylmethyldimethoxysilane, while the other preparation steps remained the same as those in Example 1, to obtain the modified siloxane of Comparative Example 1.

[0048] Comparative Example 2 In step S2, tetramethylcyclotetrasiloxane was replaced with 1,1,3,3-tetramethyldisiloxane, while the other preparation steps remained the same as those in Example 1, to obtain the modified siloxane of Comparative Example 2.

[0049] Comparative Example 3 In step S3, 4-vinylepoxycyclohexane was replaced with vinyl glycidyl ether, while the other preparation steps remained the same as in Example 1, to obtain the modified siloxane of Comparative Example 3.

[0050] Comparative Example 4 Purchase a commercially available photo- and moisture-curing dual-curing siloxane product, whose main component is an acrylic polyurethane-modified organosilicon polysiloxane compound.

[0051] Performance testing By weight, under a light-proof and nitrogen atmosphere, 2 parts of diphenyl-(4-phenylthio)phenylsulfonium hexafluoroantimonate and 2 parts of propylene carbonate were mixed evenly, and then 100 parts of Examples 1 to 8 or Comparative Examples 1 to 3 (Comparative Example 4 was a commercially available finished product and did not require additional formulation adjustments) and 1 part of di(dodecylthio)dibutyltin were added sequentially. The mixture was mixed evenly in a high-speed mixer, and after defoaming and filtration, the corresponding test samples were obtained.

[0052] The modified polysiloxane materials prepared in each embodiment and comparative example were subjected to Shore hardness testing according to the test method of GB / T 531.1-2008. The tensile strength of the modified polysiloxane materials prepared in each embodiment and comparative example was tested according to the test method of GB / T 528-2009. The thermal properties of the modified polysiloxane materials prepared in each embodiment and comparative example were tested using a Pyris 1 thermogravimetric analyzer under a nitrogen atmosphere. T5% represents the thermal decomposition temperature corresponding to a 5% sample mass loss, T10% represents the thermal decomposition temperature corresponding to a 10% sample mass loss, and the 800℃ residue represents the carbon residue mass retention rate when the sample is heated to 800℃. Higher values ​​for these three indicators indicate better thermal stability of the material. The test results are recorded in Table 1 below.

[0053] Table 1 Performance test results of each embodiment and comparative example

[0054] In Examples 1-3, the amount of phenylmethyldimethoxysilane coupling agent was gradually increased, and the strength, toughness, and thermal stability of the modified polysiloxane material cured by both light and moisture were simultaneously improved. Compared with Examples 1, 4, and 5, the amounts of 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, tetramethylcyclotetrasiloxane, and 4-vinylepoxycyclohexane were simultaneously increased, and the mechanical and thermal properties of the material were continuously improved. This indicates that increasing the grafting ratio of cyclic siloxanes and epoxy functional groups can increase the curing crosslinking density of the modified polysiloxane material cured by both light and moisture, strengthen the proportion of spindle-shaped structures, and further improve the overall performance of the product material.

[0055] By adjusting the amount of 4-vinylepoxycyclohexane in Examples 1 and 6-8, the curing crosslinking density of the modified polysiloxane material cured by both light and moisture can be increased. Furthermore, the alicyclic structure and phenyl and cyclic siloxanes form a synergistic effect, achieving a simultaneous improvement in the strength and toughness of the product material.

[0056] In Comparative Example 1, the phenylmethyldimethoxysilane coupling agent was replaced with octylmethyldimethoxysilane, resulting in the absence of phenyl groups in the product structure. In Comparative Example 2, tetramethylcyclotetrasiloxane was replaced with 1,1,3,3-tetramethyldisiloxane, which disrupted the cyclic branched structure and spindle-shaped structure of the product in this application. In Comparative Example 3, 4-vinylepoxycyclohexane was replaced with vinyl glycidyl ether, changing the terminal alicyclic epoxy functional group to a glycidyl ether type epoxy.

[0057] The modified polysiloxane materials prepared in Comparative Examples 1 to 3 all showed inferior performance compared to the scheme described in this application. The modified polysiloxane material with dual curing of light and moisture in this application, through structural design, constructs a spindle-shaped modified polysiloxane structure using three molecular structures: phenyl-modified main chain, cyclic siloxane grafting, and alicyclic epoxy functionalization. Functionally, it achieves dual curing effects of ultraviolet light and moisture, solving the problem that single ultraviolet light cannot cure shadow areas and thick coatings. In terms of performance, it achieves simultaneous improvement in mechanical strength, toughness, and thermal stability, and its overall performance is superior to similar products on the market.

[0058] In summary, this application successfully prepared a modified polysiloxane capable of dual curing under light and moisture by employing a stepwise synthesis process, sequentially involving alkali-catalyzed ring-opening polymerization and a two-step hydrosilylation reaction. Through a rational molecular structure design, this method introduces phenyl structural units into the polysiloxane backbone while grafting alicyclic epoxy groups onto cyclic siloxanes as branching nodes. This endows the material with dual curing characteristics under both UV and moisture conditions, effectively overcoming the limitations of single-light curing systems in achieving complete curing of shaded areas, thick coatings, and colored systems, thus improving curing efficiency and sufficiency. Furthermore, the synergistic effect of the phenyl groups, cyclic branching structures, and alicyclic epoxy groups significantly improves the material's mechanical properties and thermal stability. In addition, the hydrogen-containing cyclic siloxane modified intermediate obtained during the preparation process exhibits good reactivity, allowing for the expansion of material properties through grafting different functional groups. This provides a new technical approach for the preparation and application of high-performance dual-curing organosilicon materials.

[0059] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this application. Various changes and modifications can be made to this application without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection claimed by this application is defined by the appended claims and their equivalents.

Claims

1. A modified polysiloxane that undergoes both light and moisture curing, characterized in that, Its structural formula is: , where R is either epoxycyclohexyl or trimethoxysilyl, and the same structure contains both R groups, 1≤m≤20, 99≤n≤999.

2. A method for preparing a photo- and moisture-cured modified polysiloxane, characterized in that, The preparation steps include the following: S1: The first intermediate product is prepared by reacting a mixed cyclic dimethylsiloxane, a phenylmethyldimethoxysilane coupling agent, and 1,3-divinyl-1,1,3,3-tetramethyldisiloxane under alkaline catalytic conditions. S2: The first intermediate product is reacted with tetramethylcyclotetrasiloxane under the action of a first catalyst to obtain the second intermediate product; S3: The modified polysiloxane with photo-moisture dual curing is prepared by reacting the second intermediate with 4-vinylepoxycyclohexane and vinyltrimethoxysilane under the action of a second catalyst; The structural formula of the first intermediate product is: Where 1≤m≤20, 99≤n≤999; The structural formula of the second intermediate product is: , where 1≤m≤20, 99≤n≤999.

3. The preparation method according to claim 2, characterized in that, The mass ratio of the phenylmethyldimethoxysilane coupling agent to the dimethylsiloxane mixed ring is 1:(1~99).

4. The preparation method according to claim 2, characterized in that, The mass ratio of the 1,3-divinyl-1,1,3,3-tetramethyldisiloxane to the dimethylsiloxane mixed ring is 1:(1~999).

5. The preparation method according to claim 2, characterized in that, The molar ratio of the first intermediate product to the tetramethylcyclotetrasiloxane is (1~5):(2~10).

6. The preparation method according to claim 2, characterized in that, The molar ratio of the second intermediate product to the 4-vinylepoxycyclohexane is (1~5):(2~10).

7. The preparation method according to claim 2, characterized in that, The S1 step specifically involves: under an inert gas atmosphere, adding the dimethylsiloxane mixed cyclic compound, the phenylmethyldimethoxysilane coupling agent, and the 1,3-divinyl-1,1,3,3-tetramethyldisiloxane to a reaction vessel, adding an alkaline catalyst, heating to 120~180 ℃, maintaining the temperature for 6~8 h, and removing low-boiling substances for 2~4 h to obtain the first intermediate product.

8. The preparation method according to claim 2, characterized in that, The S2 step specifically involves adding the first intermediate product, the tetramethylcyclotetrasiloxane, and isopropanol to a reaction vessel under an inert gas atmosphere, adding the first catalyst, and heating to 95-150 °C. The reaction is maintained at this temperature for 4-6 h until the material system becomes transparent, thereby obtaining the second intermediate product.

9. The preparation method according to claim 2, characterized in that, The S3 step specifically involves adding the second intermediate product and the 4-vinylepoxycyclohexane and vinyltrimethoxysilane to a reaction vessel under an inert gas atmosphere. Then, a second catalyst is added and the temperature is raised to 95-150 °C. The reaction is maintained at this temperature for 4-6 h until the material system becomes transparent. After removing low-boiling substances for 2-4 h, the modified polysiloxane with photo-moisture dual curing is obtained.

10. The preparation method according to claim 2, characterized in that, The alkaline catalyst is potassium hydroxide or tetramethylammonium hydroxide, and both the first catalyst and the second catalyst are caster catalysts.

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