Phosphate / Ti / Bi composite catalyst as well as preparation method and application thereof
By developing phosphate/Ti/Bi composite catalysts in dealcoholized room temperature vulcanized silicone rubber, the environmental and health risks of organotin catalysts and the attenuation of activity of organotitanium catalysts are solved, and the effect of high stability and rapid curing is achieved.
Patent Information
- Application Number
- CN202510477286.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-16
- Publication Date
- 2025-06-10
Smart Images
Figure CN120118318A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of silicone materials, and particularly relates to a phosphate / Ti / Bi composite catalyst, a preparation method thereof, and an application thereof. Background Art
[0002] One-component room temperature vulcanizing silicone rubber (RTV-1) is widely used in fields such as aerospace, high-speed rail, and 5G due to its excellent weather resistance, high and low temperature resistance, etc. RTV-1 is mainly divided into types such as alcohol-eliminating type, oxime-eliminating type, and acid-eliminating type. Among them, the alcohol-eliminating type room temperature vulcanizing silicone rubber is more environmentally friendly and odorless compared to oxime-eliminating type products and acid-eliminating type products because methanol molecules are eliminated during the curing process. The alcohol-eliminating type room temperature vulcanizing silicone rubber is usually prepared from hydroxyl-terminated polysiloxane or alkoxy-terminated polysiloxane as the base polymer, fumed silica or calcium carbonate as the filler, methyltrimethoxysilane or tetraethyl orthosilicate as the crosslinking agent, organotin or chelated tin as the catalyst, silane coupling agent as the tackifier, and silicone oil as the plasticizer. Currently, the alcohol-eliminating type one-component room temperature vulcanizing silicone rubber uses organotin as the main catalyst and organotitanium as the auxiliary catalyst. However, organotin compounds have significant impacts on the environment and human health, including endocrine disruption, nervous system damage, and immune system suppression, etc., and their use is restricted in many countries or regions in consumer products. Currently, organotitanium catalysts are primary titanium complexes and secondary titanium complexes. When used alone as the catalyst for alcohol-type silicone rubber, it will cause a serious decline in the storage stability of alcohol-eliminating type RTV-1, and the catalytic activity will rapidly decay during storage, losing the curing ability. At the same time, the system will thicken during the rubber preparation process, showing a viscosity peak. In the one-component alcohol-eliminating type room temperature vulcanizing silicone rubber, when using organotitanium (primary titanium complex and secondary titanium complex) catalyst alone in the prior art, due to the influence of residual moisture in the system during the product storage process, the catalytic performance of the titanium complex will be severely reduced, resulting in the situation that the silicone rubber does not cure.
[0003] Therefore, it is of great significance to develop a new type of highly stable catalyst to replace the organotin catalyst to meet the use requirements of alcohol-eliminating type room temperature vulcanizing silicone rubber and solve the problem of the short storage period of alcohol-eliminating type room temperature vulcanizing silicone rubber. Summary of the Invention
[0004] The present invention provides a phosphate / Ti / Bi composite catalyst, a preparation method thereof, and an application thereof. This catalyst has both high catalytic activity and high stability. When applied to alcohol-eliminating type room temperature vulcanizing silicone rubber, it can replace the organotin catalyst to realize the preparation of tin-free alcohol-eliminating type room temperature vulcanizing silicone rubber, and the product has the advantages of fast curing speed and stable storage.
[0005] The technical solution of the present invention is as follows:
[0006] In the first aspect, a preparation method of a phosphate / Ti / Bi composite catalyst is disclosed, including the following steps:
[0007] 1) React tetraalkyl titanate and organobismuth by stirring in an inert atmosphere at a temperature of 70 - 100 °C for 3 - 6 h. Preferably, the reaction temperature is 80 - 90 °C and the reaction time is 4 - 5 h.
[0008] 2) Add phosphate ester to the reaction product of step 1), continue stirring and reacting for 2 - 4 h, and remove low-boiling substances by vacuum distillation to obtain the phosphate / Ti / Bi composite catalyst. Preferably, the continuous reaction time is 2.5 - 3.5 h.
[0009] Preferably, the tetraalkyl titanate is one of tetra-n-propyl titanate, tetra-isopropyl titanate, and tetra-n-butyl titanate, and more preferably tetra-isopropyl titanate.
[0010] Preferably, the organobismuth is one of bismuth isooctanoate, bismuth neodecanoate, and bismuth tert-amyl alcoholate, and more preferably bismuth isooctanoate.
[0011] Preferably, the inert atmosphere is a nitrogen atmosphere, the reaction temperature in step 2) is 70 - 100 °C, and the temperature of vacuum distillation in step 2) is 110 - 120 °C.
[0012] Preferably, the molar ratio of tetraalkyl titanate to organobismuth is 1:(0.5 - 1.5), and more preferably 1:(0.6 - 1.4).
[0013] Preferably, the phosphate ester is one of bis(2-ethylhexyl) phosphate, bis(1-chloro-2-propyl) phosphate, diphenyl phosphate, and dibutyl phosphate, and more preferably bis(2-ethylhexyl) phosphate and bis(1-chloro-2-propyl) phosphate.
[0014] Preferably, the molar ratio of tetraalkyl titanate to phosphate ester is 1:(2 - 3), and more preferably 1:(2.1 - 2.9).
[0015] In the second aspect, a phosphate / Ti / Bi composite catalyst prepared by the above preparation method is disclosed.
[0016] In the third aspect, an application of the phosphate / Ti / Bi composite catalyst in the preparation of an alcohol-free room temperature vulcanized silicone rubber is disclosed.
[0017] The present invention first reacts titanate with organic bismuth to form a concentrated coordination of Ti / Bi bimetallic ion active groups. Since bismuth ions react more vigorously with water molecules, they can effectively protect the active centers of titanium ions. By further introducing a phosphate ester structure into the structure, the Ti / Bi is prevented from being destroyed, making the Ti / Bi coordination more stable. The phosphate ester can also effectively hinder the destruction of the metal ion active centers by water molecules, so that the composite catalyst not only maintains high catalytic activity but also effectively maintains the activity stability during the storage of silicone rubber.
[0018] Compared with the prior art, the present invention has the following beneficial effects:
[0019] 1. The highly stable phosphate ester / Ti / Bi composite catalyst for the alcohol-decoupling type room temperature vulcanized silicone rubber prepared by the present invention enhances the catalytic ability through the co-synergy of introducing organic bismuth and Bi, and enhances the stability of the catalyst by introducing phosphate ester coordination, effectively inhibiting the activity attenuation during storage.
[0020] 2. Using the catalyst prepared by the present invention to prepare room temperature vulcanized silicone rubber does not contain organotin and has the advantages of fast curing speed and stable storage.
[0021] 3. The process for preparing the catalyst of the present invention is simple and has high production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 is the infrared structure schematic diagram of Catalyst 1 prepared in Example 1 of the present invention. DETAILED DESCRIPTION OF THE INVENTION
[0023] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions will be clearly and completely described below in conjunction with the embodiments of the present invention.
[0024] Example 1
[0025] The preparation method of the phosphate ester / Ti / Bi composite catalyst is as follows: 28.4 g (0.1 mol) of tetra-isopropyl titanate and 63.8 g (0.1 mol) of bismuth isooctanoate are stirred and reacted at 80 °C under a nitrogen atmosphere for 4 h, 80.5 g (0.25 mol) of bis(2-ethylhexyl) phosphate ester is added and the reaction is continued to stir at 80 °C for 3 h. Under 115 °C and a vacuum degree of -0.095 MPa, the low-boiling substances are removed until the product quality no longer changes, and a light yellow oily liquid is obtained, which is the phosphate ester / Ti / Bi composite catalyst 1. The infrared spectrum of the phosphate ester / Ti / Bi composite catalyst 1 is as Figure 1 shown, and the absorption peak at 1250 cm -1 belongs to the stretching vibration of P=O, and the absorption peak at 1100 cm -1The absorption peak at [specific value] cm⁻¹ belongs to the P-O stretching vibration, 1050 cm -1 The absorption peak at [specific value] cm⁻¹ belongs to the Ti-O-C stretching vibration, 800 cm -1 The absorption peak at [specific value] cm⁻¹ belongs to the Bi-O-Bi stretching vibration, proving the successful introduction of phosphate ester, Ti, and Bi in the catalyst.
[0026] The phosphate ester / Ti / Bi composite catalyst is used for the preparation of alcohol-free room temperature vulcanized silicone rubber. The specific method is as follows:
[0027] Dimethyl silicone oil with a viscosity of 150 mPa·s, 107 rubber with a viscosity of 20000 mPa·s, methyltrimethoxysilane, KH-560 (γ-glycidoxypropyltrimethoxysilane), phosphate ester / Ti / Bi composite catalyst I, vinyltrimethoxysilane, fumed silica, and triethyl citrate are added to a planetary disperser in a mass ratio of 40:300:30:4:8:4:40:3, and compounded evenly to obtain alcohol-free room temperature vulcanized silicone rubber. Then, the properties of the silicone rubber are tested, and its surface drying, tack-free, curing time, and tensile properties are recorded. Then, it is canned and placed in an aging oven at 90 °C for 24 h. After taking it out and cooling it to room temperature, a rubber strip is extruded, and the surface drying, tack-free, curing time, and tensile properties are observed and recorded, as shown in Table 1 specifically.
[0028] Example 2
[0029] 28.4 g (0.1 mol) of titanium tetraisopropoxide and 63.8 g (0.1 mol) of bismuth isooctanoate are stirred and reacted at 90 °C under a nitrogen atmosphere for 5 h. Then, 62.8 g (0.25 mol) of bis-(1-chloro-2-propyl) phosphate ester is added and the reaction continues to stir at 90 °C for 3 h. At 115 °C and a vacuum of -0.095 MPa, low-boiling substances are removed until the product quality no longer changes, obtaining a light yellow oily liquid, which is the phosphate ester / Ti / Bi composite catalyst II.
[0030] The phosphate ester / Ti / Bi composite catalyst is used for the preparation of alcohol-free room temperature vulcanized silicone rubber. The specific method is the same as that in Example 1, except that the phosphate ester / Ti / Bi composite catalyst I is replaced with an equal amount of the phosphate ester / Ti / Bi composite catalyst II. The properties of the prepared alcohol-free room temperature vulcanized silicone rubber are shown in Table 1.
[0031] Example 3
[0032] 34 g (0.1 mol) of tetrabutyl titanate and 72.2 g (0.1 mol) of bismuth neodecanoate were stirred and reacted at 80 °C under a nitrogen atmosphere for 4.5 h. 65.5 g (0.28 mol) of diphenyl phosphate was added and the reaction was continued with stirring at 80 °C for 3 h. Low-boiling substances were removed at 115 °C under a vacuum of -0.095 MPa until the product quality no longer changed, obtaining a pale yellow oily liquid, which is the phosphate / Ti / Bi composite catalyst III.
[0033] The phosphate / Ti / Bi composite catalyst was used for the preparation of an alcohol-eliminating room temperature vulcanized silicone rubber. The specific method was the same as that in Example 1, except that the phosphate / Ti / Bi composite catalyst I was replaced with an equal amount of the phosphate / Ti / Bi composite catalyst III. The properties of the prepared alcohol-eliminating room temperature vulcanized silicone rubber are shown in Table 1.
[0034] Example 4
[0035] 28.4 g (0.1 mol) of tetrapropyl titanate and 42.3 g (0.09 mol) of bismuth tert-amyl alcoholate were stirred and reacted at 90 °C under a nitrogen atmosphere for 4 h. 48.3 g (0.23 mol) of dibutyl phosphate was added and the reaction was continued with stirring at 90 °C for 3.5 h. Low-boiling substances were removed at 115 °C under a vacuum of -0.095 MPa until the product quality no longer changed, obtaining a pale yellow oily liquid, which is the phosphate / Ti / Bi composite catalyst IV.
[0036] The phosphate / Ti / Bi composite catalyst was used for the preparation of an alcohol-eliminating room temperature vulcanized silicone rubber. The specific method was the same as that in Example 1, except that the phosphate / Ti / Bi composite catalyst I was replaced with an equal amount of the phosphate / Ti / Bi composite catalyst IV. The properties of the prepared alcohol-eliminating room temperature vulcanized silicone rubber are shown in Table 1.
[0037] Example 5
[0038] 34 g (0.1 mol) of tetrabutyl titanate and 82.9 g (0.13 mol) of bismuth isooctanoate were stirred and reacted at 85 °C under a nitrogen atmosphere for 5 h. 55.2 g (0.22 mol) of bis-(1-chloro-2-propyl) phosphate was added and the reaction was continued with stirring at 85 °C for 2.5 h. Low-boiling substances were removed at 115 °C under a vacuum of -0.095 MPa until the product quality no longer changed, obtaining a pale yellow oily liquid, which is the phosphate / Ti / Bi composite catalyst V.
[0039] The phosphate / Ti / Bi composite catalyst was used for the preparation of an alcohol-eliminating room temperature vulcanized silicone rubber. The specific method was the same as that in Example 1, except that the phosphate / Ti / Bi composite catalyst I was replaced with an equal amount of the phosphate / Ti / Bi composite catalyst V. The properties of the prepared alcohol-eliminating room temperature vulcanized silicone rubber are shown in Table 1.
[0040] Example 6
[0041] 28.4 g (0.1 mol) of tetra-isopropyl titanate and 32.9 g (0.07 mol) of bismuth tert-pentoxide were stirred and reacted under a nitrogen atmosphere at 90 °C for 4 h. Then, 58.5 g (0.25 mol) of diphenyl phosphate was added and the reaction was continued with stirring at 90 °C for 3.5 h. Low-boiling substances were removed at 115 °C under a vacuum of -0.095 MPa until the product quality no longer changed, obtaining a pale yellow oily liquid, which was the phosphate / Ti / Bi composite catalyst VI.
[0042] The phosphate / Ti / Bi composite catalyst was used to prepare an alcohol-eliminating room temperature vulcanized silicone rubber. The specific method was the same as that in Example 1, except that the phosphate / Ti / Bi composite catalyst I was replaced with an equal amount of the phosphate / Ti / Bi composite catalyst VI. The properties of the prepared alcohol-eliminating room temperature vulcanized silicone rubber are shown in Table 1.
[0043] Example 7
[0044] 28.4 g (0.1 mol) of tetra-n-propyl titanate and 36.1 g (0.05 mol) of bismuth neodecanoate were stirred and reacted under a nitrogen atmosphere at 70 °C for 6 h. Then, 64.4 g (0.2 mol) of bis(2-ethylhexyl) phosphate was added and the reaction was continued with stirring at 70 °C for 4 h. Low-boiling substances were removed at 115 °C under a vacuum of -0.095 MPa until the product quality no longer changed, obtaining a pale yellow oily liquid, which was the phosphate / Ti / Bi composite catalyst VII.
[0045] The phosphate / Ti / Bi composite catalyst was used to prepare an alcohol-eliminating room temperature vulcanized silicone rubber. The specific method was the same as that in Example 1, except that the phosphate / Ti / Bi composite catalyst I was replaced with an equal amount of the phosphate / Ti / Bi composite catalyst VII. The properties of the prepared alcohol-eliminating room temperature vulcanized silicone rubber are shown in Table 1.
[0046] Example 8
[0047] 34 g (0.1 mol) of tetra-n-butyl titanate and 70.5 g (0.15 mol) of bismuth tert-pentoxide were stirred and reacted under a nitrogen atmosphere at 100 °C for 3 h. Then, 63 g (0.3 mol) of dibutyl phosphate was added and the reaction was continued with stirring at 100 °C for 2 h. Low-boiling substances were removed at 115 °C under a vacuum of -0.095 MPa until the product quality no longer changed, obtaining a pale yellow oily liquid, which was the phosphate / Ti / Bi composite catalyst VIII.
[0048] The phosphate / Ti / Bi composite catalyst was used to prepare an alcohol-eliminating room temperature vulcanized silicone rubber. The specific method was the same as that in Example 1, except that the phosphate / Ti / Bi composite catalyst I was replaced with an equal amount of the phosphate / Ti / Bi composite catalyst VIII. The properties of the prepared alcohol-eliminating room temperature vulcanized silicone rubber are shown in Table 1.
[0049] Comparative Example 1
[0050] Prepare a de-alcoholic room temperature vulcanizing silicone rubber, and the specific method is as follows:
[0051] Add dimethyl silicone oil with a viscosity of 150 mPa·s, 107 rubber with a viscosity of 20,000 mPa·s, methyltrimethoxysilane, KH-560 (γ-glycidoxypropyltrimethoxysilane), tetra-isopropyl titanate, vinyltrimethoxysilane, fumed silica, and triethyl citrate in a mass ratio of 40:300:30:4:8:4:40:3 to a planetary disperser for uniform compounding to obtain silicone rubber. Then test the properties of the silicone rubber, record its surface drying, tack-free, curing time, and tensile properties, and then put it into a 90°C aging oven for 24 h after canning. After taking it out and cooling it to room temperature, extrude the rubber strip, and observe and record the surface drying, tack-free, curing time, and tensile properties, as shown in Table 1 specifically.
[0052] Comparative Example 2
[0053] Prepare a de-alcoholic room temperature vulcanizing silicone rubber, and the specific method is as follows:
[0054] Add dimethyl silicone oil with a viscosity of 150 mPa·s, 107 rubber with a viscosity of 20,000 mPa·s, methyltrimethoxysilane, KH-560 (γ-glycidoxypropyltrimethoxysilane), bismuth isooctanoate, vinyltrimethoxysilane, fumed silica, and triethyl citrate in a mass ratio of 40:300:30:4:8:4:40:3 to a planetary disperser for uniform compounding to obtain silicone rubber. Then test the properties of the silicone rubber, record its surface drying, tack-free, curing time, and tensile properties, and then put it into a 90°C aging oven for 24 h after canning. After taking it out and cooling it to room temperature, extrude the rubber strip, and observe and record the surface drying, tack-free, curing time, and tensile properties, as shown in Table 1 specifically.
[0055] Comparative Example 3
[0056] Prepare a de-alcoholic room temperature vulcanizing silicone rubber, and the specific method is as follows:
[0057] Dimethyl silicone oil with a viscosity of 150 mPa·s, 107 rubber with a viscosity of 20,000 mPa·s, methyltrimethoxysilane, KH-560 (γ-glycidoxypropyltrimethoxysilane), bis(2-ethylhexyl) phosphate, vinyltrimethoxysilane, fumed silica, and triethyl citrate were added to a planetary disperser in a mass ratio of 40:300:30:4:8:4:40:3, and compounded evenly to obtain silicone rubber. The properties of the silicone rubber were tested, and its surface drying, tack-free, curing time, and tensile properties were recorded. Then, it was canned and placed in an aging oven at 90 °C for 24 h. After taking it out and cooling it to room temperature, a rubber strip was extruded, and the surface drying, tack-free, curing time, and tensile properties were observed and recorded, as shown in Table 1 specifically.
[0058] Comparative Example 4
[0059] Different from Example 1, the addition amount of bismuth isooctanoate in this comparative example is 114.9 g (0.18 mol), and the remaining preparation methods and steps are the same as those in Example 1. The performance test results of the silicone rubber are shown in Table 1.
[0060] Comparative Example 5
[0061] Different from Example 1, the temperature of the stirring reaction of tetra-isopropyl titanate and bismuth isooctanoate is replaced from 80 °C to 110 °C, and the temperature of the reaction after adding bis(2-ethylhexyl) phosphate is replaced from 80 °C to 110 °C. The remaining preparation methods and steps are the same as those in Example 1. The performance test results of the silicone rubber are shown in Table 1.
[0062] Comparative Example 6
[0063] Different from Example 1, the preparation method of the composite catalyst is as follows: 28.4 g (0.1 mol) of tetra-isopropyl titanate and 80.5 g (0.25 mol) of bis(2-ethylhexyl) phosphate were stirred and reacted at 80 °C under a nitrogen atmosphere for 3 h. At 115 °C and a vacuum of -0.095 MPa, low-boiling substances were removed until the product quality no longer changed, and a composite catalyst was obtained.
[0064] The remaining preparation methods and steps are the same as those in Example 1. The performance test results of the silicone rubber are shown in Table 1.
[0065] Comparative Example 7
[0066] Different from Example 1, the preparation method of the composite catalyst is as follows: 28.4 g (0.1 mol) of tetra-isopropyl titanate and 63.8 g (0.1 mol) of bismuth isooctanoate were stirred and reacted at 80 °C under a nitrogen atmosphere for 4 h. At 115 °C and a vacuum of -0.095 MPa, low-boiling substances were removed until the product quality no longer changed, and a composite catalyst was obtained.
[0067] The remaining preparation methods and steps are the same as those in Example 1, and the performance test results of the silicone rubber are shown in Table 1.
[0068] Comparative Example 8
[0069] Different from Example 1, the preparation method of the composite catalyst is as follows: 28.4 g (0.1 mol) of tetra-isopropyl titanate and 63.8 g (0.1 mol) of bismuth isooctanoate are stirred and reacted at 80 °C under a nitrogen atmosphere for 8 h, 80.5 g (0.25 mol) of bis(2-ethylhexyl) phosphate is added and the reaction is continued by stirring at 80 °C for 6 h, and the low-boiling substances are removed at 115 °C under a vacuum of -0.095 MPa until the product quality no longer changes, obtaining the composite catalyst.
[0070] The remaining preparation methods and steps are the same as those in Example 1, and the performance test results of the silicone rubber are shown in Table 1.
[0071] Table 1
[0072]
[0073]
[0074] It should be noted that non-curing in Table 1 means non-curing in 7 days during the experiment. If it still does not cure after 7 days, it has no meaning in the actual application process, so it has no practical application value.
[0075] The alcohol-based adhesive prepared by using the phosphate / Ti / Bi composite catalyst prepared in Examples 1-8 of the present invention has reasonable surface drying, tack-free and curing times, the tensile strength is above 2.4 MPa, the elongation at break is above 300%, there is no viscosity peak during the preparation process, and after aging at 90 °C for 1 day, it can still maintain the surface drying, tack-free and curing properties, and the performance of the sealant decays slightly.
[0076] For the alcohol-type sealant prepared with the traditional phthalate catalyst in Comparative Example 1, the tensile strength and elongation at break are slightly poor, and there is an obvious viscosity peak during the preparation process. Although it has reasonable surface drying, tack-free and curing times under conventional conditions, it has no curing ability after aging at 90 °C for 1 day. In Comparative Example 2, an organic bismuth catalyst is used instead of the phosphate / Ti / Bi composite catalyst, and the surface drying and tack-free times are too long and it cannot cure within seven days. In Comparative Example 3, a phosphate is used instead of the phosphate / Ti / Bi composite catalyst to prepare the alcohol-type sealant and it cannot cure. The main reason is that the phosphate cannot provide metal active centers and cannot form a stable coordination structure, so curing cannot be achieved. In Comparative Example 4, the addition amount of bismuth isooctanoate is too much. Compared with Example 1, although it can cure normally, the surface drying, tack-free and curing times are prolonged under conventional and aging conditions, and the performance decreases significantly. This is because the excessive addition of bismuth isooctanoate makes the content of the phosphate / Ti / Bi composite catalyst per unit mass of the prepared catalyst decrease, and the catalytic performance weakens.
[0077] In Comparative Example 5 and Comparative Example 8, higher reaction temperatures or longer reaction times were respectively adopted. The prepared catalyst was dark blackish red in color. Although the surface drying, tack-free, curing times and properties after conventional and aging were all good after making the glue, the color of the colloid was yellowish, which affected the appearance. At the same time, the higher reaction temperature and longer reaction time increased the energy consumption.
[0078] In Comparative Example 6 and Comparative Example 7, Ti reacted only with phosphate ester and organic bismuth respectively to prepare the catalyst. Since its structure was unstable compared with the catalyst prepared in the examples of the present invention, the obtained alcohol-based glue had longer surface drying, tack-free and curing times, and the tensile strength and elongation at break were not as good as those in the examples of the present application. Moreover, after aging at 90 °C for 1 day, all indexes decayed significantly.
[0079] Although the present invention has been described in detail by way of preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, those of ordinary skill in the art can make various equivalent modifications or substitutions to the embodiments of the present invention, and these modifications or substitutions should all be within the scope covered by the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims
1. A method for preparing a phosphate ester / Ti / Bi composite catalyst, characterized in that: The following steps are involved: 1) stirring titanate and organic bismuth at 70-100° C. in an inert atmosphere for 3-6 hours; 2) adding the phosphate ester to the reaction product of step 1), continuing the stirring reaction for 2-4 hours, and removing the low-boiling substances by vacuum distillation to obtain the phosphate ester / Ti / Bi composite catalyst.
2. The method for preparing the phosphate ester / Ti / Bi composite catalyst according to claim 1, characterized in that: The titanate is one of tetra-n-propyl titanate, tetra-isopropyl titanate and tetra-n-butyl titanate.
3. The method for preparing the phosphate ester / Ti / Bi composite catalyst according to claim 1, characterized in that: The organic bismuth is one of bismuth isooctanoate, bismuth neodecanoate and bismuth tert-amyl alcohol.
4. The method for preparing the phosphate ester / Ti / Bi composite catalyst according to claim 1, characterized in that: The inert atmosphere is a nitrogen atmosphere, the reaction temperature in step 2) is 70-100°C, and the temperature of the reduced pressure distillation in step 2) is 110-120°C.
5. The method for preparing the phosphate ester / Ti / Bi composite catalyst according to claim 1, characterized in that: The molar ratio of titanate to organic bismuth is 1:(0.5-1.5).
6. The method for preparing the phosphate ester / Ti / Bi composite catalyst according to claim 1, characterized in that: The phosphate ester is one of di(2-ethylhexyl)phosphate, bis-(1-chloro-2-propyl)phosphate, diphenyl phosphate and dibutyl phosphate.
7. The method for preparing the phosphate ester / Ti / Bi composite catalyst according to claim 1, characterized in that: The molar ratio of titanate to phosphate is 1:(2-3).
8. The phosphate ester / Ti / Bi composite catalyst prepared by the preparation method according to any one of claims 1 to 7.
9. Use of the phosphate ester / Ti / Bi composite catalyst as claimed in claim 8 in the preparation of dealcoholization type room temperature vulcanized silicone rubber.