Silicone ester-based flexible vulcanizable material and preparation method thereof

Abstract

The invention relates to the technical field of high polymer materials, in particular to an estersil-based flexible vulcanizable material and a preparation method thereof. The silicone rubber composition is prepared from the following components in parts by mass: 60 to 80 parts of silicone rubber, 25 to 35 parts of polyurethane, 5 to 15 parts of an organic solvent, 3 to 8 parts of a softener, 0.5 to 1.5 parts of a coupling agent, 0.1 to 0.5 part of a cross-linking agent, 5 to 15 parts of reinforcing carbon black, 0.2 to 1 part of polyol, 0.1 to 0.3 part of chitosan and 0.5 to 1.5 parts of tert-butyl peroxide phthalate. The estersil-based flexible vulcanizable material prepared by adopting the formula provided by the invention has excellent performance in wrinkle resistance, breaking strength, elongation at break, tear strength and adhesive property, and can meet the use requirements of vortex-induced vibration suppression towing cable-ribbon type products.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to a silicone ester-based flexible vulcanizable material and a preparation method thereof. Background Art

[0002] Silicone rubber and polyurethane are two common polymer materials. Silicone rubber has excellent weather resistance, insulation and physiological inertness, while polyurethane has high strength, high elasticity and high wear resistance. However, their respective limitations are also very obvious.

[0003] There are many literatures available on the blending and modification of silicone rubber and polyurethane materials. Most of these studies are conducted at the laboratory level on the interfacial tension, mechanical properties, and biocompatibility of the blended materials, but there is no research on the application level of industrial products, such as tear strength, flexibility and wrinkle resistance, high temperature and UV resistance, chemical adhesion, and difficulty in mass production.

[0004] When developing and producing vortex-induced vibration suppression towline-ribbon products, we encountered the problems of poor wrinkle resistance of polyurethane and poor strength and chemical bonding of silicone rubber. Therefore, it is necessary to develop a silicone rubber-polyurethane blended modified material that meets the requirements of high strength, good toughness, wrinkle resistance and recovery, and chemical bonding. Summary of the invention

[0005] In order to solve the problems mentioned in the above background technology, the present invention provides a silicone-based flexible vulcanizable material and a preparation method thereof.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: The first aspect of the present invention provides a silicone ester-based flexible vulcanizable material, which comprises, by weight: 60-80 parts of silicone rubber, 25-35 parts of polyurethane, 5-15 parts of organic solvent, 3-8 parts of softener, 0.5-1.5 parts of coupling agent, 0.1-0.5 parts of cross-linking agent, 5-15 parts of reinforcing carbon black, 0.2-1 parts of polyol, 0.1-0.3 parts of chitosan and 0.5-1.5 parts of tert-butyl peroxide phthalate.

[0007] Preferably, the organic solvent is any one of tetrahydrofuran, ethanol and acetone.

[0008] Preferably, the softener is trioctyl phosphate and the coupling agent is tetrapropoxysilane.

[0009] Preferably, the cross-linking agent is a di-tetra-sulfurizing agent, and the polyol is ethylene glycol or glycerol.

[0010] The present invention also provides a method for preparing a silicone ester-based flexible vulcanizable material, comprising the following steps: The silicone rubber and the cross-linking agent are mixed by a rubber mixing device, and reinforcing carbon black is added and continued to be mixed to obtain the mixed silicone rubber; Dispersing chitosan and tert-butyl peroxide phthalate in an organic solvent, then coating the mixed silicone rubber surface, and irradiating the mixed silicone rubber with an ultraviolet lamp to obtain activated silicone rubber; Add the activated silicone rubber, polyurethane, coupling agent and organic solvent into another rubber mixing equipment, heat up until the materials are completely melted, add softener and mix, make sheets, cool down, coat one side of the sheets with polyol, put into pre-made weak alkaline water, and make the side coated with polyol contact with the water surface; Finally, the vulcanization treatment is carried out in a vulcanizer to obtain a silicone ester-based flexible vulcanizable material.

[0011] Preferably, the mixing conditions of the silicone rubber and the cross-linking agent are: 50-100° C., 10-30 min; the conditions for adding reinforcing carbon black and continuing mixing are: 170-190° C., 3-10 min.

[0012] Preferably, the ultraviolet lamp irradiation time is 1-5 minutes.

[0013] Preferably, the conditions for adding the softener and kneading are: 120-200° C., 10-30 min.

[0014] Preferably, the weak alkaline water is prepared by adding anhydrous sodium carbonate into pure water, adjusting the pH to 8, and adjusting the water temperature to 65°C-70°C.

[0015] Preferably, the conditions of the vulcanization treatment are: 1-5 MPa, 50-100° C., 10 min.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The silicone-based flexible vulcanizable material prepared by the formula of the present invention has excellent performance in wrinkle resistance, breaking strength, breaking elongation, tear strength, and bonding performance, and can meet the use requirements of vortex-induced vibration suppression towline-streamer type products.

[0017] 2. The formula of the present invention uses chitosan and tert-butyl peroxide phthalate. When the two are added at the same time, a synergistic enhancement effect is produced. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a physical picture of the vortex-induced vibration suppression towline-ribbon type product.

[0019] Figure 2 This is a real picture of the streamer obtained from the silicone-based flexible vulcanizable material in Example 1. DETAILED DESCRIPTION

[0020] Unless otherwise specified, the raw materials and reagents used in the present invention are commercially available or can be prepared by known methods.

[0021] Among them, silicone rubber: Wacker R401 / 70A, Shanghai Yazhu Chemical Technology Co., Ltd.; Polyurethane: IROGRANA85P4394, Huntsman Chemical Trading (Shanghai) Co., Ltd.; Example 1

[0022] A silicone ester-based flexible vulcanizable material comprises, by weight, 70 parts of silicone rubber, 30 parts of polyurethane, 10 parts of organic solvent, 5 parts of softener, 1 part of coupling agent, 0.3 parts of cross-linking agent, 10 parts of reinforcing carbon black, 0.5 parts of polyol, 0.2 parts of chitosan and 1 part of tert-butyl peroxide phthalate.

[0023] The method for preparing a silicone ester-based flexible vulcanizable material comprises the following steps: The silicone rubber and the crosslinking agent are mixed by a rubber mixing device at 75°C for 20 minutes; reinforcing carbon black is added and mixed for 5 minutes at 180°C. After the mixing is completed, the material temperature is maintained at 35-40°C to obtain the mixed silicone rubber; Dispersing chitosan and tert-butyl peroxide phthalate in tetrahydrofuran, then coating the mixed silicone rubber surface, and irradiating with ultraviolet light for 3 minutes to obtain activated silicone rubber; Add the activated silicone rubber, polyurethane, coupling agent and tetrahydrofuran into another rubber mixing equipment, heat up until the materials are completely melted, add softener, mix at 185℃ for 20min; make into a sheet with a thickness of 1mm, cool down to 70℃, coat one side of the sheet with ethylene glycol, put into pre-made weak alkaline water (the preparation method of weak alkaline water is: add anhydrous sodium carbonate to pure water, adjust the pH to 8, and adjust the water temperature to 65℃-70℃), and the side coated with ethylene glycol is in contact with the water surface; Finally, the vulcanization treatment is carried out in a vulcanizer under the vulcanization conditions of 3MPa, 70°C, and 10min to obtain a silicone-based flexible vulcanizable material. Example 2

[0024] The difference between this embodiment and embodiment 1 is that the silicone rubber is 60 parts, and the rest is exactly the same as that of embodiment 1. Example 3

[0025] The difference between this embodiment and embodiment 1 is that the silicone rubber is 80 parts, and the rest is exactly the same as embodiment 1. Example 4

[0026] The difference between this embodiment and embodiment 1 is that the polyurethane is 25 parts, and the rest is exactly the same as embodiment 1. Example 5

[0027] The difference between this embodiment and embodiment 1 is that the polyurethane is 35 parts, and the rest is exactly the same as embodiment 1.

[0028] Comparative Example 1 The difference between this comparative example and Example 1 is that there is 0 part of chitosan, and the rest is exactly the same as Example 1.

[0029] Comparative Example 2 The difference between this comparative example and Example 1 is that: 0 part of tert-butyl peroxide phthalate is used, and the rest is exactly the same as Example 1.

[0030] Comparative Example 3 The difference between this comparative example and Example 1 is that: 0 parts of chitosan and 0 parts of tert-butyl peroxide phthalate, and the rest are exactly the same as in Example 1.

[0031] Results and Testing Wrinkle resistance: Prefabricate a film with a length and width of 300mm and a bottom thickness of 1mm, fold it in half, press it with a 1kg weight, and then release it for 24 hours to compare the recovery of the crease; Breaking strength, breaking elongation, tearing strength: tested in accordance with GJB 1916A-2022.

[0032] Adhesion: The tear strength between the cold vulcanized material and the vulcanized rubber is tested according to GJB 1916A-2022. The results are shown in Table 1.

[0033] Table 1

[0034] It can be seen from Examples 1-5 in Table 1 that the silicone-based flexible vulcanizable material prepared using the formula of the present invention has excellent performance in wrinkle resistance, breaking strength, elongation at break, tear strength, and bonding performance, and can meet the use requirements of vortex-induced vibration suppression towline-streamer type products.

[0035] By comparing Example 1 and Comparative Examples 1-3, it can be seen that the addition of chitosan and tert-butyl peroxide phthalate has an important influence on the final performance of the product, such as adhesion. The adhesion of the product without chitosan and only tert-butyl peroxide phthalate is 38.4 N / mm (Comparative Example 1), and the adhesion of the product without tert-butyl peroxide phthalate and only chitosan is 33.2 N / mm (Comparative Example 2). When both are missing, the adhesion is reduced to 30.1 N / mm (Comparative Example 3). When both are added at the same time, the adhesion is increased to 48.6 N / mm (Example 1), indicating that when the two are added at the same time, a synergistic enhancement effect is produced. The possible reason is that chitosan contains a large number of hydroxyl and amino groups, and tert-butyl phthalate peroxide contains carboxyl and oxidizing peroxy groups. When the two are added at the same time, on the one hand, the surface roughness of the silicone rubber is increased and the van der Waals force between the molecules is enhanced, and on the other hand, the film-forming ability of the silicone rubber is improved. After subsequent blending with polyurethane and heating, the polyurethane is quickly melted, and the ester group, ether bond and broken silicon oxygen bond form new chemical bonds under the joint action of coupling agents and organic solvents. The addition of softener interacts with the hydroxyl and carboxyl groups on the surface of the material to form a very strong orientation and adsorption, and the chemical bonding properties of the hydrophilic group are further improved by coating with polyols.

[0036] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A silicone-based flexible vulcanizable material, characterized in that: Calculated by mass, it includes: 60-80 parts of silicone rubber, 25-35 parts of polyurethane, 5-15 parts of organic solvent, 3-8 parts of softener, 0.5-1.5 parts of coupling agent, 0.1-0.5 parts of cross-linking agent, 5-15 parts of reinforcing carbon black, 0.2-1 parts of polyol, 0.1-0.3 parts of chitosan and 0.5-1.5 parts of tert-butyl peroxide.

2. A silicone-based flexible vulcanizable material according to claim 1, characterized in that: The organic solvent is any one of tetrahydrofuran, ethanol and acetone.

3. A silicone-based flexible vulcanizable material according to claim 1, characterized in that: The softener is trioctyl phosphate, and the coupling agent is tetrapropoxy silane.

4. A silicone-based flexible vulcanizable material according to claim 1, characterized in that: The cross-linking agent is a di-tetra-sulfurizing agent, and the polyol is ethylene glycol or propylene glycol.

5. A method for preparing the silicone ester-based flexible vulcanizable material according to any one of claims 1 to 4, characterized in that: The steps include: The silicone rubber and the cross-linking agent are mixed by a rubber mixing device, and reinforcing carbon black is added and continued to be mixed to obtain the mixed silicone rubber; Dispersing chitosan and tert-butyl peroxide phthalate in an organic solvent, then coating the mixed silicone rubber surface, and irradiating the mixed silicone rubber with an ultraviolet lamp to obtain activated silicone rubber; Add the activated silicone rubber, polyurethane, coupling agent and organic solvent into another rubber mixing equipment, heat up until the materials are completely melted, add softener and mix, make sheets, cool down, coat one side of the sheets with polyol, put into pre-made weak alkaline water, and make the side coated with polyol contact with the water surface; Finally, the vulcanization treatment is carried out in a vulcanizer to obtain a silicone ester-based flexible vulcanizable material.

6. The method for preparing a silicone ester-based flexible vulcanizable material according to claim 5, characterized in that: The mixing conditions of the silicone rubber and the crosslinking agent are: 50-100° C., 10-30 min; the conditions for adding reinforcing carbon black and continuing mixing are: 170-190° C., 3-10 min.

7. The method for preparing a silicone-based flexible vulcanizable material according to claim 5, characterized in that: The ultraviolet light irradiation time is 1-5min.

8. The method for preparing a silicone-ester-based flexible vulcanizable material according to claim 5, characterized in that: The conditions for adding softener and kneading are: 120-200℃, 10-30min.

9. The method for preparing a silicone-ester-based flexible vulcanizable material according to claim 5, characterized in that: The weak alkaline water is prepared by adding anhydrous sodium carbonate into pure water, adjusting the pH to 8, and adjusting the water temperature to 65° C.-70° C.

10. The method for preparing a silicone ester-based flexible vulcanizable material according to claim 5, characterized in that: The conditions of the vulcanization treatment are: 1-5MPa, 50-100°C, 10min.

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