Sulfuryl-containing polyorganosilsesquioxane flame retardant and preparation method thereof

Abstract

The invention relates to the field of flame retardant preparation, in particular to a sulfuryl-containing polysilsesquioxane compound and a preparation method thereof, and the compound is suitable for being used as a flame retardant in polycarbonate materials. The invention discloses a sulfuryl-containing polyorganosilsesquioxane, the compound has an RSO2CH2CH2SiO1.5 unit, and the structure of the compound is as follows: # imgabs0 #, in which R is equal to C4H9 and C8H17. The invention further discloses a preparation method of the sulfuryl-containing polyorganosilsesquioxane. Vinyltrimethoxysilane and mercaptan which are rich in source and low in price are used as reactants, free radical addition, oxidation and hydrolytic condensation reaction are carried out, novel polysilsesquioxane containing sulfuryl is obtained, reaction conditions are mild, and the yield is high.

Description

Technical Field

[0001] The invention relates to the field of flame retardant preparation, in particular to a sulfone-containing polyorganosilisesquioxane compound and a preparation method thereof. The compound is suitable for being used as a flame retardant in polycarbonate materials. Technical Background

[0002] Polymer plastics are mainly composed of carbon, hydrogen and oxygen, which have the disadvantage of being extremely flammable and posing a fire hazard during application. Therefore, in order to meet the fire protection requirements of polymer materials, flame retardants need to be added to improve their flame retardant properties. Silicon-based flame retardants are called "green" flame retardants. They are easy to process and have significant flame retardant effects. They are a new type of high-efficiency, low-smoke, low-toxic, anti-drip, and environmentally friendly halogen-free flame retardant. Sulfur-based flame retardants are flame retardants containing sulfur elements in their structure. They have a highly efficient flame retardant effect on polycarbonate, but they also have some defects. For example, PC materials with sulfur-based flame retardants have poor water resistance. In order to further improve the flame retardant effect of sulfur-based flame retardants in PC, some synergists such as siloxanes and fluorinated polymers need to be added.

[0003] As various industries have higher and higher requirements for PC flame retardancy, the flame retardant efficiency of flame retardants with a single flame retardant element often cannot meet special needs. Therefore, synergistic flame retardant technology has gradually been developed to compound a single type of flame retardant to form an efficient flame retardant system containing multiple flame retardant elements. The flame retardant effect of this system is better than the sum of the single components, and it can achieve the effect of 1+1>2, which can reduce the amount of flame retardant while meeting the high flame retardant requirements of the material.

[0004] Patent 201010128415.9 provides a method for preparing polysilsesquioxane containing DOPO groups, and hydrolyzes and condenses silane with DOPO groups to obtain cage-type oligomeric silsesquioxanes. By combining flame retardant elements phosphorus and silicon, the flame retardant, mechanical and other properties of the polymer can be improved. Patent CN 202311313304.9 provides a method for preparing an organosilicon sulfonate flame retardant, and copolymerizes 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane and 3,3-disulfonic acid biphenyl di(amidobenzoic acid) as polymerization monomers to obtain an organosilicon polyaromatic amide sulfonate flame retardant. Through the synergistic effect of sulfonate and silicon, the problem of poor high temperature resistance and flame retardancy of polycarbonate is solved. Patent CN202411069827.8 discloses a flame retardant and toughening agent containing phosphorus and silicon elements, and its preparation method and application. It is prepared from a phosphorus-containing compound and 2,4,6-trimethyl-2,4,6-trivinylcyclotrisiloxane. The phosphorus and silicon elements can simultaneously improve the flame retardant properties and mechanical properties of the material, but the reaction temperature is high.

[0005] Although many flame retardants with synergistic effects of multiple elements with silicon as the main body have been developed, the amount added is still relatively large, and the flame retardant efficiency needs to be further improved. Therefore, the development of new sulfur- and silicon-containing flame retardants with simple preparation, high flame retardant efficiency and low addition amount has become an urgent need in the field of flame retardant polymer technology. Summary of the invention

[0006] The problem to be solved by the present invention is to provide a polyorganosilisesquioxane compound containing sulfone groups and a preparation method thereof. The polyorganosilisesquioxane compound is a novel compound containing sulfur and silicon elements at the same time and has a good synergistic flame retardant effect in polycarbonate.

[0007] The technical solution for realizing the present invention is:

[0008] The invention discloses a polyorganosilsesquioxane containing a sulfone group, the compound having RSO2CH2CH2SiO 1.5 The unit structure is as follows:

[0009]

[0010] Where R=C4H9,C8H 17 .

[0011] The method for preparing the sulfone-containing polyorganosilsesquioxane as shown in formula (I) of the present invention comprises the following steps: in an organic solvent I, vinyltrimethoxysilane reacts with 1 mole of mercaptan in the presence of a free radical initiator, an oxidant is added to react after removing the solvent, and the sulfone-containing polyorganosilsesquioxane is obtained by post-treatment with hydrolysis.

[0012] The specific steps include:

[0013] 1) In a reactor equipped with a stirrer, a thermometer, and a reflux condenser, an organic solvent, vinyltrimethoxysilane, a mercaptan, and a free radical initiator are added, the reaction temperature is controlled at 70-90° C., the reaction time is 4-6 hours, and the solvent is removed by rotary evaporation to obtain alkylthiotrimethoxysilane;

[0014] 2) adding an oxidant and an organic solvent to the alkylthiotrimethoxysilane obtained in step 1), controlling the reaction temperature to 20-30° C. (preferably 30° C.), the reaction time to 2-3 hours, and removing the solvent by rotary evaporation to obtain alkylsulfonetrimethoxysilane;

[0015] 3) adding 4 times the mass of deionized water to the alkylsulfone trimethoxysilane obtained in step 2), carrying out hydrolysis and condensation reaction, controlling the reaction temperature at 20-30° C., the reaction time at 8-10 hours, filtering, washing, and drying at 100° C. to obtain polyorganosilsesquioxane containing sulfone groups.

[0016] In the above step 1), the organic solvent is acetonitrile, acetone or tetrahydrofuran (preferably acetonitrile), and the ratio of its volume to the mass of vinyltrimethoxysilane is 10-20 ml:1 g;

[0017] In the above step 1), the mercaptan is 1-butyl mercaptan or 1-octanethiol, and its amount is 0.8-1 times the molar amount of vinyltrimethoxysilane;

[0018] The free radical initiator in the above step 1) is azobisisobutyronitrile or azobisisoheptanenitrile, and its amount is 0.03-0.05 times the molar amount of vinyltrimethoxysilane;

[0019] In the above step 2), the organic solvent is methanol or ethanol, and the ratio of its volume to the mass of alkylthiotrimethoxysilane is 5-10 ml:1 g;

[0020] The oxidant in the above step 2) is 30% concentration of hydrogen peroxide, and its amount is 3 to 5 times the molar amount of alkylthiotrimethoxysilane, preferably 5 times.

[0021] In addition, the present invention also provides a flame retardant, comprising a sulfone-containing polyorganosilsesquioxane represented by the structural formula (1).

[0022] The polyorganosilsesquioxane containing sulfone groups represented by the structural formula (1) is used for improving the flame retardant properties of polycarbonate materials.

[0023] Compared with the prior art, the present invention has the following significant advantages:

[0024] (1) The present invention uses vinyltrimethoxysilane and mercaptan, which are abundant in source and low in price, as reactants to obtain a novel sulfone-containing polyorganosilsesquioxane through free radical addition, oxidation and hydrolysis condensation reactions. The reaction conditions are mild and the yield is high.

[0025] (2) Sulfone polysilsesquioxane flame retardant has sulfone group and siloxy group, which can play a flame retardant role in both gas phase and condensed phase by releasing non-combustible gas sulfur dioxide and insulating layer silicon dioxide during the combustion of polycarbonate. It has the advantages of high flame retardant efficiency, good carbonization, good structure and material compatibility, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is the FT-IR graph of the target product a in Example 1.

[0027] Figure 2 This is the FT-IR graph of the target product b in Example 2. DETAILED DESCRIPTION

[0028] In order to better understand the present invention, the technical solution of the present invention is specifically described below through specific embodiments.

[0029] Example 1

[0030] In a reactor equipped with a stirrer, a thermometer, and a reflux condenser, 1.48 g (10 mmol) of vinyl trimethoxysilane, 0.9 g (10 mol) of 1-butanethiol, 81 mg (5 mol%) of azobisisobutyronitrile and 20 mL of acetonitrile were added, and the mixture was stirred at 90°C for 4 h. After the reaction was completed, the mixture was cooled to room temperature and part of the solvent was removed by rotary evaporation. Subsequently, 3.4 g (30 mmol) of 30% hydrogen peroxide and 20 mL of methanol were added, and the mixture was stirred at 30°C for 2 h. Stirring was stopped, part of the solvent was removed by rotary evaporation, and 10 mL of deionized water was added. The mixture was stirred at 30°C for 8 h, and the mixture was filtered and washed with methanol to obtain a white product, which was then dried in an oven to obtain butyl sulfone polysilsesquioxane with a yield of 80%.

[0031] The infrared characterization data are as follows:

[0032] FT-IR(KBr,cm -1 ): 3435(Si-OH),2870-2965(C4H9,CH2-CH2),1320&1265(SO2),1130&1040(Si-O-Si).

[0033] Example 2

[0034] In a reactor equipped with a stirrer, a thermometer, and a reflux condenser, 1.48 g (10 mmol) of vinyl trimethoxysilane, 1.46 g (10 mol) of 1-octanethiol, 81 mg (5 mol%) of azobisisobutyronitrile and 20 mL of acetonitrile were added, and the mixture was stirred at 90°C for 4 h. After the reaction was completed, the mixture was cooled to room temperature and part of the solvent was removed by rotary evaporation. Subsequently, 3.4 g (30 mmol) of 30% hydrogen peroxide and 15 mL of methanol were added, and the mixture was stirred at 30°C for 2 h. Stirring was stopped, part of the solvent was removed by rotary evaporation, and 10 mL of deionized water was added. The mixture was stirred at 30°C for 8 h, and the mixture was filtered and washed with methanol to obtain a white product, which was then dried in an oven to obtain octyl sulfone polysilsesquioxane with a yield of 82%.

[0035] The infrared characterization data are as follows:

[0036] FT-IR(KBr,cm -1 ): 3430(Si-OH), 2850-2960(C8H 17 ,CH2-CH2),1320&1260(SO2),1130&1040(Si-O-Si).

[0037] Example 3

[0038] In a reactor equipped with a stirrer, a thermometer, and a reflux condenser, 1.48 g (10 mmol) of vinyl trimethoxysilane, 1.17 g (8 mol) of 1-octanethiol, 81 mg (5 mol%) of azobisisobutyronitrile and 20 mL of acetonitrile were added, and the mixture was stirred at 90°C for 4 h. After the reaction was completed, the mixture was cooled to room temperature and part of the solvent was removed by rotary evaporation. Subsequently, 3.4 g (30 mmol) of 30% hydrogen peroxide and 15 mL of methanol were added, and the mixture was stirred at 30°C for 2 h. Stirring was stopped, part of the solvent was removed by rotary evaporation, and 10 mL of deionized water was added. The mixture was stirred at 30°C for 8 h, and the mixture was filtered and washed with methanol to obtain a white product, which was then dried in an oven to obtain octyl sulfone polysilsesquioxane with a yield of 63%.

[0039] Example 4

[0040] In a reactor equipped with a stirrer, a thermometer, and a reflux condenser, 1.48 g (10 mmol) of vinyl trimethoxysilane, 0.9 g (10 mol) of 1-butanethiol, 81 mg (5 mol%) of azobisisobutyronitrile and 20 mL of acetonitrile were added, and the mixture was stirred at 70°C for 6 h. After the reaction was completed, the mixture was cooled to room temperature and part of the solvent was removed by rotary evaporation. Subsequently, 3.4 g (30 mmol) of 30% hydrogen peroxide and 15 mL of methanol were added, and the mixture was stirred at 30°C for 2 h. Stirring was stopped, part of the solvent was removed by rotary evaporation, and 10 mL of deionized water was added. The mixture was stirred at 30°C for 8 h, filtered, washed with methanol, and a white product was obtained. The product was dried in an oven to obtain butyl sulfone polysilsesquioxane with a yield of 78%.

[0041] Example 5

[0042] In a reactor equipped with a stirrer, a thermometer, and a reflux condenser, 1.48 g (10 mmol) of vinyl trimethoxysilane, 0.9 g (10 mol) of 1-butanethiol, 81 mg (5 mol%) of azobisisobutyronitrile and 20 mL of acetonitrile were added, and the mixture was stirred at 90°C for 4 h. After the reaction was completed, the mixture was cooled to room temperature and part of the solvent was removed by rotary evaporation. Subsequently, 3.4 g (30 mmol) of 30% hydrogen peroxide and 15 mL of methanol were added, and the mixture was stirred at 20°C for 3 h. The stirring was stopped, part of the solvent was removed by rotary evaporation, and 10 mL of deionized water was added. The mixture was stirred at 30°C for 8 h, and the mixture was filtered and washed with methanol to obtain a white product, which was then dried in an oven to obtain butyl sulfone polysilsesquioxane with a yield of 76%.

[0043] Example 6

[0044] In a reactor equipped with a stirrer, a thermometer, and a reflux condenser, 1.48 g (10 mmol) of vinyl trimethoxysilane, 0.9 g (10 mol) of 1-butanethiol, 81 mg (5 mol%) of azobisisobutyronitrile and 20 mL of acetonitrile were added, and the mixture was stirred at 90°C for 4 h. After the reaction was completed, the mixture was cooled to room temperature and part of the solvent was removed by rotary evaporation. Subsequently, 3.4 g (30 mmol) of 30% hydrogen peroxide and 15 mL of methanol were added, and the mixture was stirred at 30°C for 2 h. Stirring was stopped, part of the solvent was removed by rotary evaporation, and 10 mL of deionized water was added. The mixture was stirred at 20°C for 10 h, filtered, washed with methanol, and a white product was obtained. The product was dried in an oven to obtain butyl sulfone polysilsesquioxane with a yield of 75%.

[0045] Example 7

[0046] In a reactor equipped with a stirrer, a thermometer, and a reflux condenser, 1.48 g (10 mmol) of vinyl trimethoxysilane, 0.9 g (10 mol) of 1-butanethiol, 81 mg (5 mol%) of azobisisobutyronitrile and 25 mL of acetone were added, and the mixture was stirred at 90°C for 4 h. After the reaction was completed, the mixture was cooled to room temperature and part of the solvent was removed by rotary evaporation. Subsequently, 3.4 g (30 mmol) of 30% hydrogen peroxide and 15 mL of methanol were added, and the mixture was stirred at 30°C for 2 h. Stirring was stopped, part of the solvent was removed by rotary evaporation, and 10 mL of deionized water was added. The mixture was stirred at 30°C for 8 h, filtered, washed with methanol, and a white product was obtained. The product was dried in an oven to obtain butyl sulfone polysilsesquioxane with a yield of 77%.

[0047] Example 8

[0048] In a reactor equipped with a stirrer, a thermometer, and a reflux condenser, 1.48 g (10 mmol) of vinyl trimethoxysilane, 0.9 g (10 mol) of 1-butanethiol, 81 mg (5 mol%) of azobisisobutyronitrile and 15 mL of tetrahydrofuran were added, and the mixture was stirred at 90°C for 4 h. After the reaction was completed, the mixture was cooled to room temperature and part of the solvent was removed by rotary evaporation. Subsequently, 3.4 g (30 mmol) of 30% hydrogen peroxide and 15 mL of methanol were added, and the mixture was stirred at 30°C for 2 h. Stirring was stopped, part of the solvent was removed by rotary evaporation, and 10 mL of deionized water was added. The mixture was stirred at 30°C for 8 h, filtered, washed with methanol, and a white product was obtained. The product was dried in an oven to obtain butyl sulfone polysilsesquioxane with a yield of 65%.

[0049] Example 9

[0050] In a reactor equipped with a stirrer, a thermometer, and a reflux condenser, 1.48 g (10 mmol) of vinyl trimethoxysilane, 0.9 g (10 mol) of 1-butanethiol, 81 mg (5 mol%) of azobisisobutyronitrile and 20 mL of acetonitrile were added, and the mixture was stirred at 90°C for 4 h. After the reaction was completed, the mixture was cooled to room temperature and part of the solvent was removed by rotary evaporation. Subsequently, 3.4 g (30 mmol) of 30% hydrogen peroxide and 30 mL of ethanol were added, and the mixture was stirred at 30°C for 2 h. Stirring was stopped, part of the solvent was removed by rotary evaporation, and 10 mL of deionized water was added. The mixture was stirred at 30°C for 8 h, filtered, washed with methanol, and a white product was obtained. The product was dried in an oven to obtain butyl sulfone polysilsesquioxane with a yield of 74%.

[0051] Example 10

[0052] In a reactor equipped with a stirrer, a thermometer, and a reflux condenser, 1.48 g (10 mmol) of vinyl trimethoxysilane, 0.9 g (10 mol) of 1-butanethiol, 74.4 mg (5 mol%) of azobisisoheptanitrile and 20 mL of acetonitrile were added, and the mixture was stirred at 90°C for 4 h. After the reaction was completed, the mixture was cooled to room temperature and part of the solvent was removed by rotary evaporation. Subsequently, 3.4 g (30 mmol) of 30% hydrogen peroxide and 15 mL of methanol were added, and the mixture was stirred at 30°C for 2 h. Stirring was stopped, part of the solvent was removed by rotary evaporation, and 10 mL of deionized water was added. The mixture was stirred at 30°C for 8 h, and the mixture was filtered and washed with methanol to obtain a white product, which was then dried in an oven to obtain butyl sulfone polysilsesquioxane with a yield of 79%.

[0053] Embodiment 11

[0054] In a reactor equipped with a stirrer, a thermometer, and a reflux condenser, 1.48 g (10 mmol) of vinyl trimethoxysilane, 0.9 g (10 mol) of 1-butanethiol, 49 mg (3 mol%) of azobisisobutyronitrile and 20 mL of acetonitrile were added, and the mixture was stirred at 90°C for 4 h. After the reaction was completed, the mixture was cooled to room temperature and part of the solvent was removed by rotary evaporation. Subsequently, 3.4 g (30 mmol) of 30% hydrogen peroxide and 15 mL of methanol were added, and the mixture was stirred at 30°C for 2 h. Stirring was stopped, part of the solvent was removed by rotary evaporation, and 10 mL of deionized water was added. The mixture was stirred at 30°C for 8 h, filtered, washed with methanol, and a white product was obtained. The product was dried in an oven to obtain butyl sulfone polysilsesquioxane with a yield of 71%.

[0055] Example 12

[0056] In a reactor equipped with a stirrer, a thermometer, and a reflux condenser, 1.48 g (10 mmol) of vinyl trimethoxysilane, 0.9 g (10 mol) of 1-butanethiol, 81 mg (5 mol%) of azobisisobutyronitrile and 20 mL of acetonitrile were added, and the mixture was stirred at 90°C for 4 h. After the reaction was completed, the mixture was cooled to room temperature and part of the solvent was removed by rotary evaporation. Subsequently, 5.7 g (50 mmol) of 30% hydrogen peroxide and 30 mL of ethanol were added, and the mixture was stirred at 30°C for 2 h. Stirring was stopped, part of the solvent was removed by rotary evaporation, and 10 mL of deionized water was added. The mixture was stirred at 30°C for 8 h, and the mixture was filtered and washed with methanol to obtain a white product, which was then dried in an oven to obtain butyl sulfone polysilsesquioxane with a yield of 80%.

[0057] The above embodiments do not limit the present invention in any way, and any technical solutions obtained by equivalent replacement or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A sulfone-containing polyorganosilsesquioxane, characterized in that: The compound has RSO2CH2CH2SiO 1.5 The unit structure is as follows: Where R=C4H9,C8H 17 .

2. The method for preparing the sulfone-containing polyorganosilsesquioxane according to claim 1, wherein vinyltrimethoxysilane reacts with 1 mole of mercaptan in an organic solvent I in the presence of a free radical initiator, an oxidant is added to react after removing the solvent, and the sulfone-containing polyorganosilsesquioxane is obtained by post-treatment with hydrolysis.

3. The preparation method according to claim 2, characterized in that: The organic solvent I is acetonitrile, acetone or tetrahydrofuran, and the ratio of its volume to the mass of vinyltrimethoxysilane is 10-20ml:1g.

4. The preparation method according to claim 2, characterized in that: The mercaptan is 1-butanethiol or 1-octanethiol, and the molar amount thereof is 0.8-1 times the molar amount of vinyltrimethoxysilane.

5. The preparation method according to claim 2, characterized in that: The free radical initiator is azobisisobutyronitrile or azobisisoheptanenitrile, and the molar amount thereof is 0.03-0.05 times the molar amount of vinyltrimethoxysilane.

6. The preparation method according to claim 2, characterized in that: The oxidant is 30% concentration of hydrogen peroxide, and its molar amount is 3 to 5 times the molar amount of alkylthiotrimethoxysilane.

7. The preparation method according to claim 2, characterized in that: The specific steps include: 1) adding an organic solvent, vinyltrimethoxysilane, thiol and a free radical initiator into a reactor, controlling the reaction temperature to 70-90° C., the reaction time to 4-6 hours, and removing the solvent by rotary evaporation to obtain alkylthiotrimethoxysilane; 2) adding an oxidant and an organic solvent II to the alkylthiotrimethoxysilane obtained in step 1), controlling the reaction temperature to 20-30° C. and the reaction time to 2-3 hours, and removing the solvent by rotary evaporation to obtain alkylsulfonetrimethoxysilane; 3) adding 4 times the mass of deionized water to the alkylsulfone trimethoxysilane obtained in step 2), carrying out hydrolysis and condensation reaction, controlling the reaction temperature at 20-30° C., the reaction time at 8-10 hours, filtering, washing, and drying at 100° C. to obtain polyorganosilsesquioxane containing sulfone groups.

8. The preparation method according to claim 7, characterized in that: In step 2), the organic solvent II is methanol or ethanol, and the ratio of its volume to the mass of alkylthiotrimethoxysilane is 5-10 ml:1 g.

9. A flame retardant comprising the sulfone group-containing polyorganosilsesquioxane according to claim 1.

10. Use of the sulfone group-containing polyorganosilsesquioxane according to claim 1 for improving the flame retardant properties of polycarbonate materials.

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