Oligoaminopropylsiloxane and method for synthesizing the same

Abstract

The application belongs to the technical field of oligomeric organosiloxane, and relates to a kind of oligomeric aminopropylsiloxane and a synthesis method thereof. The steps are as follows: allylamine is reacted with dimethylchlorosilane to generate substance IVa; substance IVa is hydrosilylated into substance IVb; the silicon hydride compound of substance Va is converted into the silanol compound of substance Vb; the silanol compound of substance IVb is reacted with substance V to be converted into the oligomeric aminopropylsiloxane of substance I. The four products prepared by the application are all clear and transparent oily liquids, have good fluidity and solubility, and can be stored at room temperature. The obtained substance contains a high-reactivity amino group, can not only perform addition reactions with unsaturated bonds such as epoxy groups and isothiocyanic acid groups, but also perform condensation reactions with aldehyde and ketone compounds, so that corresponding property exploration can be performed by modifying the siloxane. The method has the advantages of easy-to-obtain raw materials, simple operation, mild reaction conditions, simple post-treatment and the like, and is suitable for large-scale production.

Description

Technical Field

[0001] This invention belongs to the field of organosiloxane technology, and relates to a class of oligomeric aminopropyl siloxanes and their synthesis methods, particularly to a method for preparing oligomeric organosiloxanes with an aminoalkyl-terminated main chain. Background Technology

[0002] Oligomeric aminopropyl siloxanes can be used as intermediates in organic synthesis and the synthesis of polymers. They have strong reactivity and can be used to synthesize various siloxane polymers with amino reactive functional groups. They can be used as organosilicon copolymerization modifiers for polymers such as polyurethane, epoxy resin, polyamide, and polyimide. They can also be used as fiber finishing agents, coating additives, and mold release agents.

[0003] Organic polymers such as polyurethane, epoxy resin, polyamide, and polyimide modified with oligomeric aminopropylsiloxane are endowed with new properties (improving the flexibility, toughness, and yield of plastics, reducing internal stress, improving low-temperature impact strength, and without affecting the coatability of the products).

[0004] Similar oligomeric aminopropylsiloxanes, such as 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, are already in industrial production. However, no other methods for preparing longer-chain oligomeric aminopropylsiloxanes of this class have been reported. Summary of the Invention

[0005] This invention addresses the lack of traditional methods for preparing oligomeric aminopropyl siloxanes by proposing a new class of oligomeric aminopropyl siloxanes and their synthesis methods.

[0006] To achieve the above objectives, the present invention is implemented using the following technical solution:

[0007] The oligomeric aminopropyl organosiloxane proposed in this invention has the following structural formula:

[0008] The value of n is any one of 0, 2, 4, or 6.

[0009] The method for synthesizing oligomeric aminopropyl organosiloxanes proposed in this invention includes the following steps: (1) reacting allylamine with dimethylchlorosilane to generate substance IVa: N-dimethylsilylallylamine; (2) hydrosilylating substance IVa to substance IVb in the presence of catalyst A; (3) converting the silane compound of substance VA into the silanol compound of substance VAb; (4) reacting substance IVb with the silanol compound of substance V to convert it into oligomeric aminopropyl siloxane of substance I. Wherein catalyst A is a platinum compound.

[0010] The reaction equations for the four steps described above are as follows:

[0011] Step (1):

[0012]

[0013] Step (2):

[0014]

[0015] Step (3):

[0016]

[0017] Step (4):

[0018]

[0019] In the above steps, the value of n can be any one of 0, 2, 4, or 6.

[0020] The specific operation of step (1) is as follows: put allylamine into a container, add dimethylchlorosilane dropwise while stirring, keep the temperature at 0°C during the dropwise process, and after the dropwise addition is completed, keep the temperature at half an hour, then stir the reaction at room temperature for 3-5 hours. After the reaction product is extracted and filtered, N-dimethylsilylallylamine is obtained.

[0021] The method of the present invention can be carried out in a simple manner at atmospheric pressure and provides oligomeric polypropylsiloxanes in good yield.

[0022] Another advantage of this method is that it can use low-cost raw materials such as allylamine and dimethylchlorosilane to prepare IVa, and no other reagents are required.

[0023] When allylamine reacts with dimethylchlorosilane, especially when the amount of allylamine is at least 5 molar equivalents, a two-phase liquid mixture is formed during the reaction. The lower phase contains the hydrochloride of the amine and only a very low proportion of silazane, while the upper phase mainly contains N-dimethylsilylallylamine of formula IVa and a small amount of allylamine. Furthermore, the upper phase is essentially free of chlorides.

[0024] As a result, N-dimethylsilylallylamine for subsequent hydrogenation and silylation can be obtained through simple phase separation. Another advantage is that the allylamine can be readily and completely recovered from the lower phase by reacting with an aqueous solution of a base, such as sodium hydroxide.

[0025] In this method, based on chlorosilanes, a molar excess of allylamine is preferably used, with a minimum of 5 molar equivalents of allylamine being preferred. In this embodiment, a liquid two-phase mixture containing no solids is obtained, wherein the upper phase contains formula IVa and a low proportion of allylamine, and the lower phase contains the hydrochloride of the amine dissolved in the amine, wherein the lower phase (salt phase) is substantially free of silanes.

[0026] Allylamine can be quantitatively recovered from the lower phase and reused by adding an alkali, such as an aqueous sodium hydroxide solution, and distillation, which improves energy utilization and reduces production costs.

[0027] The specific operation of step (2) is as follows: N-dimethylsilylallylamine is stirred and heated to 70°C under nitrogen protection, then caster catalyst is added, the temperature is maintained and the reaction is carried out for 5-8 hours, and the product of hydrosilylation, formula IVb, is obtained after the reaction.

[0028] Step (3) is performed as follows: In a three-necked flask equipped with a dropping funnel, thermometer, and condenser, place dry dioxane solvent, water, and catalyst Pd / C. Stir the flask thoroughly and slowly add 1,1,3,3-tetramethyldisiloxane (Va). Maintain the temperature at 40°C during the disiloxane addition. After addition, stir the reaction mixture overnight at room temperature. Then filter the mixture through a filter medium, remove the solvent by rotary evaporation, and obtain a white crystalline material. The product is further purified from the mixture of diethyl ether and hexane by recrystallization.

[0029] The specific operation of step (4) is as follows: the product of hydrogenation silanization, formula IVb, and the silanol of general formula V are mixed and stirred overnight at room temperature under nitrogen protection. After the reaction is completed, the low-boiling-point product is removed by vacuum extraction, and the product is purified by extraction with hexane and methanol.

[0030] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0031] 1. The four products prepared by this invention are all clear and transparent oily liquids with good fluidity and solubility. They are easily soluble in common organic solvents such as petroleum ether and dichloromethane, and can be stored at room temperature.

[0032] 2. The amino group obtained by this invention has high reactivity. It can not only undergo addition reactions with unsaturated bonds such as epoxy groups and isothiocyanate groups, but also undergo condensation reactions with aldehyde and ketone compounds. By modifying the amino group, many special structures can be introduced into amino silicone oil. The properties of various modified siloxanes can be studied. It can be used as an organosilicon copolymerization modifier for polymers such as polyurethane, epoxy resin, polyamide, and polyimide. It is also an ideal material as a fiber finishing agent, coating additive, and mold release agent. Attached Figure Description

[0033] Figure 1 The above is the 1H NMR spectrum of the compound oligoaminopropyltetrasiloxane obtained in Example 1 of this invention, with the solution being deuterated chloroform.

[0034] Figure 2 The above is the hydrogen spectrum of the compound oligoaminopropyl hexasiloxane obtained in Example 2 of this invention, with the solution being deuterated chloroform.

[0035] Figure 3 The above is the hydrogen spectrum of the compound oligoaminopropyl octasiloxane obtained in Example 3 of this invention, with the solution being deuterated chloroform.

[0036] Figure 4 The above is the 1H NMR spectrum of the compound oligoaminopropyldecasiloxane obtained in Example 4 of this invention, with the solution being deuterated chloroform. Detailed Implementation

[0037] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described below with reference to specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0038] Numerous specific details are set forth in the following description to provide a thorough understanding of the invention. However, the invention may be practiced in other ways than those described herein, and therefore, the invention is not limited to the specific embodiments disclosed below. Unless otherwise specified, the following embodiments employ conventional procedures in chemical experiments.

[0039] Example 1

[0040] (1) Synthesis of N-dimethylsilylallylamine.

[0041] 42g of allylamine was added to a 250ml round-bottom flask equipped with a magnetic stirrer. 15g of dimethylchlorosilane (TISHAI (Shanghai) Chemical Industry Development Co., Ltd.) was slowly added dropwise through a constant-pressure funnel under magnetic stirring and a 0°C ice bath. After the addition was complete, the mixture was kept at 0°C for another half hour, then the ice bath was removed and the reaction was allowed to proceed overnight at room temperature. After the reaction, excess sodium hydroxide solution was used to neutralize the hydrochloric acid produced and remove excess allylamine. The solution was poured into a separatory funnel, shaken, and allowed to stand for 5 minutes. The solution separated into layers. The upper colorless liquid was obtained by extraction, which is the product N-dimethylsilylallylamine. The NMR data are as follows.

[0042] 1 HNMR (400MHz, CDCl3): δ5.92(m,1H),5.17-5.02(m,2H),4.68(s,1H)3.32(m,2H),0.14(m,6H).

[0043] (2) Synthesis of IVb.

[0044] The product N-dimethylsilylallylamine from step (1) was placed in a three-necked flask. Under nitrogen protection, the temperature was raised to 70°C, and 2-3 drops of castor catalyst (1,3-divinyl-1,1,3,3-tetramethyldisiloxane platinum (0), Shanghai Mairui Biochemical Technology Co., Ltd.) were added. The reaction was maintained at this temperature and stirred overnight. Low-boiling-point substances were removed using an oil pump to obtain a yellow liquid product. The NMR data of this product are as follows.

[0045] 1 HNMR (400MHz, (CD3)2CO): δ3.18(m,2H), 1.65(m,2H), 0.62(m,2H), 0.08(m,6H).

[0046] (3) Synthesis of 1,1,3,3-tetramethyldisilol in general formula V.

[0047] 50 ml of dioxane solvent, 3.6 g of water, and 120 mg of Pd / C were added to a flask. The mixture was stirred and heated to 40 °C at 200 rpm. 13.5 g of 1,1,3,3-tetramethyldisiloxane (Beijing Bailingwei Technology Co., Ltd.) was slowly added dropwise using a constant pressure funnel, maintaining the temperature at 40 °C throughout the addition. After the addition was complete, the temperature was lowered to room temperature and stirred overnight at room temperature. The liquid after the reaction was complete was filtered to remove Pd / C, and the solvent was removed by rotary evaporation. The product was then recrystallized in diethyl ether and n-hexane (volume ratio 1:1, total 50 ml) to obtain a white crystalline product. Its NMR data are shown below. 1 HNMR (400MHz, (CD3)2CO): δ5.02(s,2H),0.04(s,12H).

[0048] (4) Synthesis of oligomeric aminopropyl tetrasiloxane.

[0049] The product IVb from step (2) and the product 1,1,3,3-tetramethyldisilol from step (3) were placed in a reaction flask, with IVb in excess (3 molar equivalents). The mixture was stirred overnight at room temperature under nitrogen protection. After the reaction was complete, the low-boiling parts were removed by pumping out the product, and the mixture was purified by extraction with methanol and n-hexane to obtain the product oligomeric polypropyltetrasiloxane with a yield of 92%.

[0050] The product, oligomeric aminopropyl tetrasiloxane, has the following structural formula.

[0051]

[0052] The proton spectrum of oligoaminopropyltetrasiloxane is as follows: Figure 1 As shown, the NMR data are as follows.

[0053] 1HNMR (400MHz, CDCl3): δ2.67(m,4H), 1.47(m,4H), 1.14(m,4H), 0.74(m,4H), 0.1(m,27H).

[0054] Example 2

[0055] Unless otherwise specified, this embodiment is the same as embodiment 1.

[0056] (1) Synthesis of N-dimethylsilylallylamine.

[0057] 42g of allylamine was added to a 250ml round-bottom flask equipped with a magnetic stirrer. 15g of dimethylchlorosilane was slowly added dropwise through a constant-pressure funnel under ice bath conditions. After the addition was complete, the temperature was maintained at 0℃ for half an hour, then the ice bath was removed and the reaction was allowed to proceed overnight at a constant pressure. After the reaction, the hydrochloric acid produced was neutralized with sodium hydroxide aqueous solution to remove excess allylamine. The solution was poured into a separatory funnel, shaken, and allowed to stand for 5 minutes. The solution separated into layers. The upper colorless liquid was obtained by extraction, which was the product N-dimethylsilylallylamine. Its NMR data were as follows: 1 HNMR (400MHz, CDCl3): δ5.92 (m, 1H), 5.17-5.02 (m, 2H), 4.68 (s, 1H), 3.32 (m, 2H), 0.14 (m, 6H).

[0058] (2) Synthesis of IVb.

[0059] The product from step 1, N-dimethylsilylallylamine, was loaded into a three-necked flask. Under nitrogen protection, the temperature was raised to 70°C, and 2-3 drops of castor catalyst were added. The reaction was maintained at this temperature with stirring overnight. Low-boiling-point substances were removed using an oil pump to obtain a yellow liquid product. Its NMR data are as follows: 1 HNMR (400MHz, (CD3)2CO): δ3.18(m,2H), 1.65(m,2H), 0.62(m,2H), 0.08(m,6H).

[0060] (3) Synthesis of 1,1,3,3,5,5,7,7-octamethyltetrasilanol in general formula V.

[0061] This step is basically the same as step (3) in Example 1. The difference is that the raw material 1,1,3,3-tetramethyldisiloxane is replaced with 1,1,3,3,5,5,7,7-octamethyltetrasiloxane (Beijing Bailingwei Technology Co., Ltd.). After the reaction, the product 1,1,3,3,5,5,7,7-octamethyltetrasilanol is a colorless liquid. Its NMR data is as follows: 1 HNMR (400MHz, (CD3)2CO): δ6.35 (s, 2H), 0.1 (s, 24H).

[0062] (4) Synthesis of oligomeric aminopropyl hexasiloxane.

[0063] This step is basically the same as step (4) in Example 1. The difference is that the reactant 1,1,3,3-tetramethyldisilol is replaced with 1,1,3,3,5,5,7,7-octamethyltetrasilol, resulting in the product oligomeric aminopropyl hexasiloxane with a yield of 92%, and its structural formula is as follows.

[0064]

[0065] The proton NMR spectrum of the product is as follows: Figure 2 As shown. The NMR data are... 1 HNMR (400MHz, CDCl3): δ2.67(m,4H), 1.47(m,4H), 1.14(m,4H), 0.74(m,4H), 0.1(m,39H).

[0066] Example 3

[0067] Unless otherwise specified, this embodiment is the same as embodiment 1.

[0068] (1) Synthesis of N-dimethylsilylallylamine.

[0069] 42g of allylamine was added to a 250ml round-bottom flask equipped with a magnetic stirrer. 15g of dimethylchlorosilane was slowly added dropwise through a constant-pressure funnel under ice bath conditions. After the addition was complete, the temperature was maintained at 0℃ for half an hour, then the ice bath was removed and the reaction was allowed to proceed overnight at a constant pressure. After the reaction, the hydrochloric acid produced was neutralized with sodium hydroxide aqueous solution to remove excess allylamine. The solution was poured into a separatory funnel, shaken, and allowed to stand for 5 minutes. The solution separated into layers. The upper colorless liquid was obtained by extraction, which was the product N-dimethylsilylallylamine. Its NMR data were as follows: 1 HNMR (400MHz, CDCl3): δ5.92(m,1H),5.17-5.02(m,2H),4.68(s,1H)3.32(m,2H),0.14(m,6H)

[0070] (2) Synthesis of IVb.

[0071] The product from step 1, N-dimethylsilylallylamine, was loaded into a three-necked flask. Under nitrogen protection, the temperature was raised to 70°C, and 2-3 drops of castor catalyst were added. The reaction was maintained at this temperature with stirring overnight. Low-boiling-point substances were removed using an oil pump to obtain a yellow liquid product. Its NMR data are as follows: 1 HNMR (400MHz, (CD3)2CO): δ3.18(m,2H), 1.65(m,2H), 0.62(m,2H), 0.08(m,6H).

[0072] (3) Synthesis of 1,1,3,3,5,5,7,7,9,9,11,11,-dodecyl hexasilanol in general formula V.

[0073] This step is basically the same as step (3) in Example 1. The difference is that the raw material 1,1,3,3-tetramethyldisiloxane is replaced with 1,1,3,3,5,5,7,7,9,9,11,11-dodecylmethylhexasiloxane (Beijing Bailingwei Technology Co., Ltd.). After the reaction, the product 1,1,3,3,5,5,7,7,9,9,11,11-dodecylmethylhexasilanol is a colorless liquid, and its NMR data is as follows.

[0074] 1 HNMR (400MHz, (CD3)2CO): δ5.11 (s, 2H), 0.1 (m, 36H).

[0075] (4) Synthesis of oligomeric aminopropyl octasiloxane.

[0076] This step is basically the same as step (4) in Example 1. The difference is that the reactant 1,1,3,3-tetramethyldisilol is replaced with 1,1,3,3,5,5,7,7,9,9,11,11-dodecylhexasilol, resulting in the product oligomeric aminopropyl octasiloxane with a yield of 92%.

[0077] The structural formula of the product is as follows.

[0078]

[0079] Its proton spectrum is as follows Figure 3 As shown, the NMR data are HNMR (400MHz, CDCl3): δ2.67(m,4H), 1.47(m,4H), 1.14(m,4H), 0.74(m,4H), 0.1(m,51H).

[0080] Example 4

[0081] Unless otherwise specified, this embodiment is the same as embodiment 1.

[0082] (1) Synthesis of N-dimethylsilylallylamine.

[0083] 42g of allylamine was added to a 250ml round-bottom flask equipped with a magnetic stirrer. 15g of dimethylchlorosilane was slowly added dropwise through a constant-pressure funnel under ice bath conditions. After the addition was complete, the temperature was maintained at 0℃ for half an hour, then the ice bath was removed and the reaction was allowed to proceed overnight at a constant pressure. After the reaction, the hydrochloric acid produced was neutralized with sodium hydroxide aqueous solution to remove excess allylamine. The solution was poured into a separatory funnel, shaken, and allowed to stand for 5 minutes. The solution separated into layers. The upper colorless liquid was obtained by extraction, which was the product N-dimethylsilylallylamine. Its NMR data were as follows: 1 HNMR (400MHz, CDCl3): δ5.92 (m, 1H), 5.17-5.02 (m, 2H), 4.68 (s, 1H), 3.32 (m, 2H), 0.14 (m, 6H).

[0084] (2) Synthesis of IVb.

[0085] The product N-dimethylsilylallylamine from step (1) was loaded into a three-necked flask. Under nitrogen protection, the temperature was raised to 70°C, and 2-3 drops of castor catalyst were added. The reaction was maintained at this temperature with stirring overnight. Low-boiling-point substances were removed using an oil pump to obtain a yellow liquid product. Its NMR data were as follows: 1 HNMR (400MHz, (CD3)2CO): δ3.18(m,2H), 1.65(m,2H), 0.62(m,2H), 0.08(m,6H).

[0086] (3) Synthesis of 1,1,3,3,5,5,7,7,9,9,11,11,13,13,15,15-hexadecyl octasilol in general formula V.

[0087] This step is basically the same as step (3) in Example 1. The difference is that the raw material 1,1,3,3-tetramethyldisiloxane is replaced with 1,1,3,3,5,5,7,7,9,9,11,11,13,13,15,15-dodecylhexasiloxane (Beijing Bailingwei Technology Co., Ltd.). After the reaction, the product 1,1,3,3,5,5,7,7,9,9,11,11,13,13,15,15-hexadecyloctasilol is a colorless liquid, and its NMR data is as follows.

[0088] 1 HNMR (400MHz, (CD3)2CO): δ5.11 (s, 2H), 0.1 (m, 48H).

[0089] (4) Synthesis of oligomeric aminopropyl decasiloxane

[0090] This step is basically the same as step (3) in Example 1. The difference is that the reactant 1,1,3,3-tetramethyldisilol is replaced with 1,1,3,3,5,5,7,7,9,9,11,11,13,13,15,15-hexadecyloctasilol, resulting in the product oligomeric aminopropyl decasiloxane with a yield of 92%. The structural formula of this product is as follows.

[0091]

[0092] Its proton spectrum is as follows Figure 4 As shown, the NMR data are 1 HNMR (400MHz, CDCl3): δ2.67(m,4H), 1.47(m,4H), 1.14(m,4H), 0.74(m,4H), 0.1(m,63H).

[0093] The four products prepared by this invention are all clear, transparent, oily liquids with excellent fluidity and solubility. They are readily soluble in common organic solvents such as petroleum ether and dichloromethane, and can be stored at room temperature. The amino groups of the substances obtained by this invention have high reactivity; they can undergo addition reactions with unsaturated bonds such as epoxy groups and isothiocyanate groups, and also condensation reactions with aldehyde and ketone compounds. Modification of the amino groups can introduce many special structures into amino silicone oils, which is of great significance to the research of polysiloxanes. They are also ideal materials for fiber finishing agents, coating additives, and the production of release agents.

[0094] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for synthesizing oligomeric aminopropylsiloxanes, characterized in that, The steps are as follows: (1) Allylamine reacts with dimethylchlorosilane to form a two-phase liquid mixture. After phase separation, the upper phase is taken to obtain the product dimethylallylaminosilane IVa, with the following structural formula: ； (2) The product dimethylallylaminosilane IVa undergoes a hydrosilylation reaction under the action of catalyst A to obtain product IVb. The catalyst A is a platinum compound, and the structural formula of product IVb is as follows: ； (3) Substance Va reacts with water under the catalytic action of catalyst B to produce product V, wherein catalyst B is palladium on carbon; The Va structure is as follows: ； The structural formula of product V is as follows: ， (4) Product IVb reacts with product V to yield oligomeric aminopropylsiloxane, with the following structural formula: , where n can be any one of 0, 2, 4, or 6; In step (1), the molar ratio of allylamine to dimethylchlorosilane is not less than 5. Dimethylchlorosilane is added to allylamine by dropping while stirring. The dropping process is carried out in an ice bath to keep the reaction temperature at 0°C. After the dropping is completed, continue the ice bath for 0.5 h, and then react at room temperature for 3-5 h. Step (2) is carried out under a nitrogen atmosphere at a temperature of 70°C for 5-8 hours.

2. The method for synthesizing oligomeric aminopropylsiloxane according to claim 1, characterized in that, In step (3), the solvent for the reaction is dioxane. Substance Va is slowly added dropwise to a solvent containing a catalyst and water. The molar ratio of substance Va to water is 1:

2. The reaction temperature is 40°C. After the addition is complete, the mixture is stirred overnight.

3. The method for synthesizing oligomeric aminopropylsiloxane according to claim 1, characterized in that, In step (4), the reaction of product IVb with product V is carried out under a nitrogen atmosphere and under stirring.

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