Hydrophilic silicone rubber and preparation method thereof

Abstract

The invention relates to the technical field of rubber processing, in particular to hydrophilic silicone rubber and a preparation method thereof.The preparation method comprises the steps that firstly, silicone rubber and a cross-linking agent are evenly mixed according to a certain weight ratio, the mixture is poured into a polytetrafluoroethylene mold, bubbles are vacuumized, and then cross-linking curing is conducted at a certain temperature; meanwhile, maleic anhydride modified polyethylene glycol and methylbenzene are mixed according to a certain mass ratio to form a methylbenzene solution of maleic anhydride modified polyethylene glycol, and then the cured silicone rubber is placed in the methylbenzene solution of maleic anhydride modified polyethylene glycol to be subjected to swelling permeation treatment for a period of time; and cleaning the surface of the swelling permeation sample with absolute ethyl alcohol, and finally drying at a certain temperature to obtain the hydrophilic silicone rubber. According to the method, the wettability of the surface of the silicon rubber can be changed in a short time, the wettability of the surface of the silicon rubber is remarkably improved, and the original optical performance and mechanical performance of pure silicon rubber are maintained.

Description

Technical Field

[0001] The invention relates to the technical field of rubber processing, in particular to a hydrophilic silicone rubber and a preparation method thereof. Background Art

[0002] Silicone rubber has an increasingly wide range of applications due to its excellent flexibility, good transparency, and easy processing and molding properties. However, the inherent hydrophobic properties of silicone rubber limit the expansion of its application, restricting the expansion of its application areas.

[0003] The Chinese invention patent publication number CN104725658A discloses a surface hydrophilic silicone rubber film and a preparation method thereof. The surface of the silicone rubber is first ignited by ultraviolet radiation, and then the surface of the silicone rubber is treated with a silane coupling agent, and then a photosensitive substance is introduced on the surface of the silicone rubber, and finally a sulfobetaine type zwitterion is grafted on the surface of the treated silicone rubber to obtain a hydrophilic silicone rubber film.

[0004] The invention patent application with the Chinese invention patent publication number CN106046379A discloses a hydrophilic mercapto-modified silicone rubber and a preparation method thereof. The reactants octamethyltetrasiloxane, tetramethyltetravinylcyclotetrasiloxane, catalyst and end-capping agent are dehydrated and dried, and then reacted in an air-tight environment, and then the silicone rubber obtained by the reaction is mixed with white carbon black, hydroxy silicone oil and 2,5-dimethyl-2,5-bis(tert-butyl peroxide)hexane, and vulcanized to obtain vulcanized rubber, and finally the vulcanized rubber is placed in an ethanol solution containing a mercapto reagent and a photoinitiator and reacted under ultraviolet irradiation conditions to obtain a hydrophilic silicone rubber.

[0005] The above disclosed methods for preparing hydrophilic silicone rubber are relatively complex in process, high in energy consumption, involve multiple chemical substances, and are cumbersome in operation. Therefore, a simple and low-energy method is needed to solve these problems. Summary of the invention

[0006] In view of the problems in the prior art, the present invention provides a hydrophilic silicone rubber and a method for preparing the same. Based on the method of high and low temperature regulation and solidification state assisted swelling and penetration, a surfactant with a relatively low content can be distributed on the surface of the silicone rubber, thereby making the transmittance and mechanical properties of the prepared hydrophilic silicone rubber almost unchanged compared with those of the unmodified silicone rubber.

[0007] The technical solution adopted by the present invention to solve the technical problem is: a method for preparing hydrophilic silicone rubber, comprising the following preparation steps: Step 1: Weigh the silicone rubber and the cross-linking agent, stir and mix them evenly, then pour them into a polytetrafluoroethylene mold, place them in a vacuum environment to remove bubbles in the mixture, and add the cross-linking agent to cross-link to obtain semi-cross-linked silicone rubber; Step 2: adding maleic anhydride modified polyethylene glycol in an amount of 0.5 to 30 wt% of the solvent mass, and stirring to mix evenly; Step 3: Place the silicone rubber obtained in step 1 in a cutting device to cut into square pieces, and place them in the solution prepared in step 2 for swelling and penetration treatment for 10 to 120 minutes at a temperature of 40°C; Step 4: Take an appropriate amount of anhydrous ethanol to rinse the surface of the silicone rubber treated with swelling and penetration obtained in step 3, and then dry it at 100 °C for 2 h.

[0008] Preferably, the silicone rubber is polydimethylsiloxane; The cross-linking agent is silicone oil.

[0009] Preferably, the molecular weight of the polyethylene glycol in the maleic anhydride-modified polyethylene glycol is 500; The solvent is toluene.

[0010] Preferably, in step 1, the mass ratio of silicone rubber to cross-linking agent is 10:1; The silicone rubber in step 1 is polydimethylsiloxane.

[0011] Preferably, the vacuum degree in step 1 is 0.08 MPa, and the cross-linking is performed at a temperature of 50° C. for 15 min.

[0012] Preferably, the cutting device in step three comprises a support seat, a protective box is fixedly mounted on the top of the support seat, a bottom plate is arranged in the middle of the protective box, and a plurality of knife holes are arranged in the middle of the bottom plate; An upper cutting disc and a lower cutting disc are arranged in the middle of the two protection boxes. The upper cutting disc and the lower cutting disc are arranged in a staggered manner and in parallel. The upper cutting disc and the lower cutting disc are both arranged in coordination with the knife hole opened in the middle of the bottom plate. A cross bar is fixedly connected in the middle of the two protection boxes, and a cleaning brush is arranged on one side of the cross bar close to the upper cutting disc and the lower cutting disc, and the cleaning brush is arranged in coordination with the upper cutting disc and the lower cutting disc.

[0013] Specifically, a driving motor is fixedly connected to one side of the support base, an output end of the driving motor is connected to a reducer, a reducer housing is fixedly connected to one side of the support base, and an output end of the reducer is connected to a first driving gear disc.

[0014] Specifically, a transmission assembly is fixedly connected to one side of the lower cutting disk close to the first driving sprocket disk. The transmission assembly includes a middle connecting shaft, which is fixedly connected to one end of the lower cutting disk. A first gear is fixedly sleeved on the outer wall of the end of the connecting shaft. The first gear is connected to the first driving sprocket disk through a first chain transmission.

[0015] Specifically, a third gear is disposed on one side of the upper cutting disc and the lower cutting disc, and the two third gears are meshed.

[0016] Specifically, a side discharge shaft and a side feed shaft are respectively arranged on both sides of the bottom plate, and both the side discharge shaft and the side feed shaft are connected to the middle part of the support seat, wherein both the side discharge shaft and the side feed shaft are arranged obliquely.

[0017] Specifically, one end of the side feed shaft close to the bottom plate is lower than one end of the side feed shaft away from the bottom plate.

[0018] Specifically, one end of the side discharge shaft close to the bottom plate is higher than one end of the side discharge shaft away from the bottom plate.

[0019] Specifically, a discharging roller is rotatably arranged between the two protection boxes, one side of the discharging roller is connected with a roller transmission gear, a second gear is sleeved on the middle part of the connecting shaft on one side of the lower cutting disc, and the roller transmission gear is connected to the second gear through a second transmission chain.

[0020] Specifically, a first extrusion roller and a lower driven roller are arranged in the middle of one side of the two protection boxes close to the side feed shaft, and the first extrusion roller and the lower driven roller are arranged in coordination; both ends of the lower driven roller are rotatably connected with a rotating shaft, and a connecting frame is fixedly connected to the side wall of the protection box, and the connecting frame is fixedly connected to the inner wall of the protection box, and a screw is fixedly penetrated and connected to the connecting frame, and one end of the rotating shaft is sleeved on the outer wall of the screw, and an adjusting spring is sleeved on the outer wall of the screw, and the adjusting spring is tightly pressed against the rotating shaft.

[0021] Specifically, a third gear connected to one side of the upper cutting disc is provided with a third transmission gear on a side away from the upper cutting disc, a driven member is fixedly provided on one side of the first squeezing roller, and the driven member is connected to the third transmission gear through a third transmission chain.

[0022] The present invention also provides silicone rubber prepared by using the preparation method of the hydrophilic silicone rubber.

[0023] Beneficial effects of the present invention: (1) The present invention is based on the principle of swelling and penetration, so that the silicone rubber first swells in the toluene solution of the surfactant to open the internal space structure of the silicone rubber, and then uses the difference in concentration of the surfactant in the external and internal spaces of the silicone rubber as a driving force to allow the surfactant to enter the silicone rubber; at the same time, semi-curing is carried out at a low temperature, which is conducive to the expansion of the volume during swelling and leaves reaction sites.

[0024] (2) The present invention controls the swelling and penetration time so that the surfactant is distributed only in the surface layer of several hundred microns of the silicone rubber, which only changes the chemical composition and wettability of the surface layer of the silicone rubber. In most areas inside the silicone rubber, there is no surfactant, and the internal chemical composition and structure are almost unchanged. Therefore, the hydrophilic silicone rubber can maintain the transparency and mechanical properties of the original silicone rubber.

[0025] (3) The hydrophilic agent selected is a reactive hydrophilic agent, which can participate in the polymerization reaction of silicone rubber in the semi-cured state by utilizing its double bonds, thereby promoting its stable existence in the material.

[0026] (4) Compared with the prior art, the cleaning brush of the present application is placed in the gap between the upper cutting disc and the lower cutting disc during the cutting process. The cleaning brush can always clean the side walls of the upper cutting disc and the lower cutting disc to avoid the adhesion of rubber and ensure the cleanliness of the upper cutting disc and the lower cutting disc. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0028] Figure 1 is a flow chart of the preparation method of the present invention; Figure 2 It is an overall schematic diagram of the cutting device of the present invention; Figure 3 For the present invention Figure 2 Schematic diagram of the internal structure of the cutting device; Figure 4 This is a schematic diagram of the structure of the internal components of the protection box of the present invention; Figure 5 It is a schematic diagram of the three-dimensional structure of the upper cutting disc and the lower cutting disc of the present invention; Figure 6 It is a schematic diagram of the position structure of the first squeezing roller and the lower driven roller of the present invention; Figure 7 For the present invention Figure 6 Enlarged view of point A in the middle.

[0029] In the figure: 1, support base; 11, protective box; 12, bottom plate; 2. Side discharge shaft; 21. Side feed shaft; 3. driving motor; 31. speed reducer; 32. first driving gear plate; 33. first chain; 4. Transmission assembly; 41. First gear; 42. Second gear; 43. Third gear; 5. Upper cutting disc; 51. Lower cutting disc; 6. Discharging roller; 7. First extrusion roller; 71. Follower; 72. Third transmission chain; 75. Lower driven roller; 751. Connecting frame; 752. Rotating shaft; 753. Adjusting spring; 8. Cross bar; 81. Cleaning brush. DETAILED DESCRIPTION

[0030] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0031] like Figure 1-Figure 7 As shown, a method for preparing a hydrophilic silicone rubber of the present invention is characterized in that it comprises the following preparation steps: Step 1: Weigh the silicone rubber and the crosslinking agent, stir and mix them evenly, then pour them into a polytetrafluoroethylene mold, place them in a vacuum environment to remove bubbles in the mixture, add the crosslinking agent to crosslink and obtain semi-crosslinked silicone rubber; the silicone rubber is polydimethylsiloxane; the crosslinking agent is silicone oil.

[0032] The vacuum degree in the step 1 is 0.08 MPa, and the cross-linking is carried out at a temperature of 50° C. for 15 min.

[0033] The mass ratio of silicone rubber to cross-linking agent in step 1 is 10:1; the silicone rubber in step 1 is polydimethylsiloxane.

[0034] Step 2: Add maleic anhydride-modified polyethylene glycol in an amount of 0.5 to 30 wt % of the solvent mass, wherein the molecular weight of the polyethylene glycol in the maleic anhydride-modified polyethylene glycol is 500, and stir to mix evenly; the solvent is toluene.

[0035] Step 3: Place the silicone rubber obtained in step 1 in a cutting device to cut into square pieces, and place them in the solution prepared in step 2 for swelling and penetration treatment for 10 to 120 minutes at a temperature of 40°C; Step 4: Take an appropriate amount of anhydrous ethanol to rinse the surface of the silicone rubber treated with swelling and penetration obtained in step 3, and then dry it at 100 °C for 2 h.

[0036] The cutting device in step 3 comprises a support base 1, a protective box 11 is fixedly mounted on the top of the support base 1, a bottom plate 12 is arranged in the middle of the protective box 11, and a plurality of knife holes are arranged in the middle of the bottom plate 12; The upper cutting disc 5 and the lower cutting disc 51 are arranged in the middle of the two protection boxes 11. The upper cutting disc 5 and the lower cutting disc 51 are arranged in a staggered manner and in parallel. The upper cutting disc 5 and the lower cutting disc 51 are both arranged in cooperation with the knife hole opened in the middle of the bottom plate 12. A cross bar 8 is fixedly connected in the middle of the two protection boxes 11 . A cleaning brush 81 is provided on one side of the cross bar 8 close to the upper cutting disc 5 and the lower cutting disc 51 . The cleaning brush 81 is provided in cooperation with the upper cutting disc 5 and the lower cutting disc 51 .

[0037] The upper cutting disc 5 and the lower cutting disc 51 can cut the flattened rubber into a preset size. During the cutting process, the cleaning brush 81 can be used to clean the side walls of the upper cutting disc 5 and the lower cutting disc 51 to prevent the rubber from adhering. The cross bar 8 supports the cleaning brush 81. The protection box 11 plays the role of installation and support.

[0038] Specifically, a driving motor 3 is fixedly connected to one side of the support base 1 , an output end of the driving motor 3 is connected to a reducer 31 , a housing of the reducer 31 is fixedly connected to one side of the support base 1 , and an output end of the reducer 31 is connected to a first driving gear disc 32 .

[0039] The driving motor 3 is turned on, and the output end of the driving motor 3 drives the first driving gear plate 32 to rotate through the reducer 31 .

[0040] Specifically, the lower cutting disc 51 is fixedly connected to a transmission assembly 4 on one side close to the first driving sprocket disc 32. The transmission assembly 4 includes a middle connecting shaft, which is fixedly connected to one end of the lower cutting disc 51. A first gear 41 is fixedly sleeved on the outer wall of the end of the connecting shaft. The first gear 41 is connected to the first driving sprocket disc 32 through a first chain 33.

[0041] A third gear 43 is disposed on one side of the upper cutting disc 5 and the lower cutting disc 51 , and the two third gears 43 are meshed with each other.

[0042] The first driving gear disc 32 drives the first gear 41 to rotate through the first chain 33. At this time, the connecting shaft rotates to drive the third gear 43 on the side of the lower cutting disc 51 to rotate, and at the same time drives the third gear 43 on the side of the upper cutting disc 5. The upper cutting disc 5 and the lower cutting disc 51 rotate at the same time to achieve the cutting of the rubber.

[0043] Specifically, a side discharge shaft 2 and a side feed shaft 21 are respectively arranged on both sides of the bottom plate 12, and the side discharge shaft 2 and the side feed shaft 21 are both connected to the middle of the support seat 1, wherein the side discharge shaft 2 and the side feed shaft 21 are both arranged obliquely; An end of the side feed shaft 21 close to the bottom plate 12 is lower than an end of the side feed shaft 21 away from the bottom plate 12; One end of the side discharge shaft 2 close to the bottom plate 12 is higher than the other end of the side discharge shaft 2 away from the bottom plate 12 .

[0044] The side feed shaft 21 is tilted to facilitate the falling of the rubber raw material, and the side discharge shaft 2 is tilted to facilitate the sliding of the cut rubber raw material and the collection of the cut rubber raw material.

[0045] Specifically, a discharging roller 6 is rotatably arranged between the two protection boxes, one side of the discharging roller 6 is connected with a roller transmission gear, a second gear 42 is sleeved on the middle part of the connecting shaft on one side of the lower cutting disc 51, and the roller transmission gear is connected to the second gear 42 through a second transmission chain.

[0046] The discharging roller 6 can be used to squeeze the cut rubber again. At the same time, the discharging roller 6 can slowly rotate to control the speed at which the cut rubber slides down along the bottom plate 12. At this time, the discharging roller 6 plays a blocking role, and the rubber squeezed by the discharging roller 6 slides down along the side discharging shaft 2. During the rotation of the first gear 41, the second gear 42 is driven to rotate synchronously through the connecting shaft. During the rotation of the second gear 42, the roller transmission gear can be driven to rotate through the second transmission chain. At this time, the discharge roller 6 rotates synchronously with the roller transmission gear.

[0047] Specifically, the first extrusion roller 7 and the lower driven roller 75 are arranged in the middle part of one side of the two protection boxes 11 close to the side feed shaft 21, and the first extrusion roller 7 and the lower driven roller 75 are arranged in coordination; the two ends of the lower driven roller 75 are rotatably connected with the rotating shaft 752, and the side wall of the protection box 11 is fixedly connected with a connecting frame 751, and the connecting frame 751 is fixedly connected to the inner wall of the protection box 11, and the connecting frame 751 is fixedly connected with a screw, and one end of the rotating shaft 752 is sleeved on the outer wall of the screw, and the outer wall of the screw is sleeved with an adjusting spring 753, and the adjusting spring 753 is tightly pressed against the rotating shaft 752.

[0048] The rubber is pressurized by the cooperation of the first squeezing roller 7 and the lower driven roller 75. When harder impurities enter the first squeezing roller 7 and the lower driven roller 75, the lower driven roller 75 will move downward to make way. At this time, the adjustment spring 753 will be compressed, thereby avoiding damage to the first squeezing roller 7 and the lower driven roller 75.

[0049] Specifically, a third transmission gear is provided on the side of the third gear 43 connected to one side of the upper cutting disc 5 away from the upper cutting disc 5 , a follower 71 is fixedly provided on one side of the first squeezing roller 7 , and the follower 71 is connected to the third transmission gear through a third transmission chain 72 .

[0050] When the third gear 43 connected to one side of the upper cutting disc 5 rotates, the third transmission gear is driven to rotate. During the rotation process, the third transmission gear drives the follower 71 to rotate synchronously through the third transmission chain 72. When the follower 71 rotates, it can drive the first squeezing roller 7 to rotate.

[0051] Working principle of the cutting equipment: When processing rubber, the rubber is placed on the side feed shaft 21 arranged on one side of the bottom plate 12. The side feed shaft 21 is arranged at an angle. The side feed shaft 21 extends to the middle of the first squeezing roller 7 and the lower driven roller 75. The rubber will enter between the first squeezing roller 7 and the lower driven roller 75. The rubber is squeezed by the first squeezing roller 7 and the lower driven roller 75. After the rubber is squeezed into a flat shape, the rubber will enter the upper surface of the bottom plate 12, wherein the bottom plate 12 is also arranged at an angle, and the rubber after squeezing can just fall onto the upper surface of the bottom plate 12. The rubber is further cut by the cooperation of the upper cutting disk 5 and the lower cutting disk 51, and the rubber is cut into a preset size for subsequent use.

[0052] During the cutting process, the cleaning brush 81 is placed in the gap between the upper cutting disk 5 and the lower cutting disk 51. The cleaning brush 81 can always clean the side walls of the upper cutting disk 5 and the lower cutting disk 51 to avoid rubber adhesion and ensure that the upper cutting disk 5 and the lower cutting disk 51 are clean.

[0053] The present invention also provides a silicone rubber which is prepared by adopting the preparation method of the hydrophilic silicone rubber.

[0054] Example 1: Weigh 10 g of silicone rubber polydimethylsiloxane and 1 g of cross-linking agent silicone oil and cure at 50 °C for 15 min. Prepare a toluene solution of surfactant maleic anhydride-modified polyethylene glycol (MEG) (weight ratio maleic anhydride-modified polyethylene glycol (MEG): toluene = 100:1). Then place the cured silicone rubber in the toluene solution of maleic anhydride-modified polyethylene glycol (MEG), maintain the temperature at 40 °C, and perform swelling and penetration treatment for 30 min. After taking out, rinse the sample after swelling and penetration treatment with anhydrous ethanol, and then dry it at 100 °C for 2 h.

[0055] Example 2: Weigh 10 g of silicone rubber polydimethylsiloxane and 1 g of cross-linking agent silicone oil and cure at 50 °C for 15 min. Prepare a toluene solution of surfactant maleic anhydride-modified polyethylene glycol (MEG) (weight ratio maleic anhydride-modified polyethylene glycol (MEG): toluene = 100:2). Then place the cured silicone rubber in the toluene solution of maleic anhydride-modified polyethylene glycol (MEG), maintain the temperature at 40 °C, and perform swelling and penetration treatment for 30 min. After taking out, rinse the sample after swelling and penetration treatment with anhydrous ethanol, and then dry it at 100 °C for 2 h.

[0056] Example 3: Weigh 10 g of silicone rubber polydimethylsiloxane and 1 g of cross-linking agent silicone oil and cure at 50 °C for 15 minutes. Prepare a toluene solution of surfactant maleic anhydride-modified polyethylene glycol (MEG) (weight ratio maleic anhydride-modified polyethylene glycol (MEG): toluene = 100:3). Then place the cured silicone rubber in the toluene solution of maleic anhydride-modified polyethylene glycol (MEG), maintain the temperature at 40 °C, and perform swelling and penetration treatment for 30 minutes. After taking out, rinse the sample after swelling and penetration treatment with anhydrous ethanol, and then dry it at 100 °C for 2 hours.

[0057] Comparative Example 1: Weigh 10 g of silicone rubber polydimethylsiloxane and 1 g of cross-linking agent silicone oil, stir and mix them evenly, then pour them into a polytetrafluoroethylene mold, and then place them in a vacuum environment to remove bubbles in the mixture. The vacuum degree is 0.08 MPa, and finally cross-link them at 100 °C for 45 min.

[0058] Comparative Example 2: Weigh 10 g of silicone rubber polydimethylsiloxane and 1 g of cross-linking agent silicone oil, then add surfactant maleic anhydride modified polyethylene glycol (MEG) (weight ratio silicone rubber: maleic anhydride modified polyethylene glycol (MEG) = 100:1), stir and mix evenly, pour into a polytetrafluoroethylene mold, and then place in a vacuum environment to remove bubbles in the mixture, the vacuum degree is 0.08 MPa, and finally cross-link at 100 °C for 45 min.

[0059] Comparative Example 3: Weigh 10 g of silicone rubber polydimethylsiloxane and 1 g of cross-linking agent silicone oil, then add surfactant maleic anhydride modified polyethylene glycol (MEG) (weight ratio of silicone rubber: maleic anhydride modified polyethylene glycol (MEG) = 100:2), stir and mix evenly, pour into a polytetrafluoroethylene mold, and then place in a vacuum environment to remove bubbles in the mixture, the vacuum degree is 0.08 MPa, and finally cross-link at 100 °C for 45 min.

[0060] Comparative Example 4: Weigh 10 g of silicone rubber polydimethylsiloxane and 1 g of cross-linking agent silicone oil, then add surfactant Triton X-100 (weight ratio of silicone rubber: maleic anhydride modified polyethylene glycol (MEG) = 100:3), stir and mix evenly, pour into a polytetrafluoroethylene mold, and then place in a vacuum environment to remove bubbles in the mixture, the vacuum degree is 0.08 MPa, and finally cross-link at 100 °C for 45 min.

[0061] Table 1 Changes in contact angle, optical properties and mechanical properties of the silicone rubber prepared in each example before and after 3 minutes

[0062] As can be seen from Table 1, when the hydrophilic silicone rubber is prepared by the swelling penetration method and the swelling time is set to 30 minutes, through the comparison of the contact angle data, the content of Triton X-100 in Example 2 is the appropriate content for the swelling penetration to reach equilibrium in the surface layer. At this time, the contact angle of water and the hydrophilic silicone rubber at the moment of contact is 66.8°, and it becomes 47.7° after 3 minutes. Compared with the pure silicone rubber (Comparative Example 1), the hydrophilic property of the silicone rubber surface is significantly improved. Through further comparison, it is found that the transmittance and mechanical properties of the hydrophilic silicone rubber prepared by the swelling penetration method are almost the same as those of pure silicone rubber (transmittance 78.9%, modulus 0.707 MPa, tensile strength 5.48MPa, elongation at break 293.97%).

[0063] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention.

Claims

1. A method for preparing a hydrophilic silicone rubber, characterized in that: The method comprises the following preparation steps: Step 1: Weigh the silicone rubber and the cross-linking agent, stir and mix them evenly, then pour them into a polytetrafluoroethylene mold, place them in a vacuum environment to remove bubbles in the mixture, and add the cross-linking agent to cross-link to obtain semi-cross-linked silicone rubber; Step 2: adding maleic anhydride-modified polyethylene glycol in an amount of 0.5 to 30 wt% of the solvent mass, and stirring to mix evenly; Step 3: Place the silicone rubber obtained in step 1 in a cutting device to cut into square pieces, and place them in the solution prepared in step 2 for swelling and penetration treatment for 10 to 120 minutes at a temperature of 40°C; Step 4: Take an appropriate amount of anhydrous ethanol to rinse the surface of the silicone rubber treated with swelling and penetration obtained in step 3, and then dry it at 100 °C for 2 h.

2. The method for preparing a hydrophilic silicone rubber according to claim 1, characterized in that: The silicone rubber is polydimethylsiloxane; The cross-linking agent is silicone oil.

3. The method for preparing a hydrophilic silicone rubber according to claim 2, characterized in that: The molecular weight of the polyethylene glycol in the maleic anhydride modified polyethylene glycol is 500; The solvent is toluene.

4. The method for preparing a hydrophilic silicone rubber according to claim 3, characterized in that: In step 1, the mass ratio of silicone rubber to cross-linking agent is 10:1; The silicone rubber in step 1 is polydimethylsiloxane.

5. The method for preparing a hydrophilic silicone rubber according to claim 4, characterized in that: The vacuum degree in the step 1 is 0.08 MPa, and the cross-linking is carried out at a temperature of 50° C. for 15 min.

6. The method for preparing a hydrophilic silicone rubber according to claim 5, characterized in that: The cutting device in step three comprises a support base (1), a protective box body (11) is fixedly mounted on the top of the support base (1), a bottom plate (12) is arranged in the middle of the protective box body (11), and a plurality of knife holes are arranged in the middle of the bottom plate (12); An upper cutting disc (5) and a lower cutting disc (51) are disposed in the middle of the two protection boxes (11); the upper cutting disc (5) and the lower cutting disc (51) are disposed in a staggered manner, and the upper cutting disc (5) and the lower cutting disc (51) are disposed in parallel; the upper cutting disc (5) and the lower cutting disc (51) are both disposed in cooperation with a knife hole provided in the middle of the bottom plate (12); A cross bar (8) is fixedly connected to the middle of the two protection boxes (11), and a cleaning brush (81) is provided on one side of the cross bar (8) close to the upper cutting disc (5) and the lower cutting disc (51), and the cleaning brush (81) is provided in cooperation with the upper cutting disc (5) and the lower cutting disc (51).

7. The method for preparing a hydrophilic silicone rubber according to claim 6, characterized in that: A drive motor (3) is fixedly connected to one side of the support base (1), an output end of the drive motor (3) is connected to a reducer (31), a housing of the reducer (31) is fixedly connected to one side of the support base (1), and an output end of the reducer (31) is connected to a first drive gear disc (32).

8. The method for preparing a hydrophilic silicone rubber according to claim 7, characterized in that: A transmission assembly (4) is fixedly connected to one side of the lower cutting disc (51) close to the first driving toothed disc (32), the transmission assembly (4) comprising a middle connecting shaft, the connecting shaft being fixedly connected to one end of the lower cutting disc (51), a first gear (41) being fixedly sleeved on the outer wall of the end of the connecting shaft, the first gear (41) being connected to the first driving toothed disc (32) via a first chain (33).

9. The method for preparing a hydrophilic silicone rubber according to claim 8, characterized in that: A third gear (43) is provided on one side of the upper cutting disc (5) and the lower cutting disc (51), and the two third gears (43) are meshed with each other.

10. The method for preparing a hydrophilic silicone rubber according to claim 9, characterized in that: A side discharge shaft (2) and a side feed shaft (21) are respectively arranged on both sides of the bottom plate (12); the side discharge shaft (2) and the side feed shaft (21) are both connected to the middle of the support seat (1); and the side discharge shaft (2) and the side feed shaft (21) are both arranged at an angle.

11. A hydrophilic silicone rubber, characterized in that: The hydrophilic silicone rubber is prepared by the method for preparing the hydrophilic silicone rubber according to any one of claims 1 to 10.

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