阅读说明：本技术 一种混合型含磷多元醇阻燃剂的制备方法 (Preparation method of mixed phosphorus-containing polyol flame retardant ) 是由 汲方奎 董晓红 毕继辉 房连顺 贾正仁 吕志锋 于 2021-02-02 设计创作，主要内容包括：一种混合型含磷多元醇阻燃剂的制备方法,属于阻燃材料技术领域,具体涉及混合型膦酸酯阻燃剂的生产工艺。在N-2氛围中,将含磷溶剂和五氧化二磷混合后再将体系冷却至室温,然后加入有机羟基化合物进行反应,得到中间体,冷却后再通入氧化烯烃,反应在停止通入氧化烯烃后继续进行,直至反应釜内压力下降至恒压时,再经老化、脱除低沸物,得混合型含磷多元醇阻燃剂。本发明工艺简单、无污染、反应条件温和、高产率,低成本。(A preparation method of a mixed phosphorus-containing polyol flame retardant belongs to the technical field of flame retardant materials, and particularly relates to a production process of a mixed phosphonate flame retardant. In N 2 In the atmosphere, mixing a phosphorus-containing solvent and phosphorus pentoxide, cooling the system to room temperature, adding an organic hydroxyl compound for reaction to obtain an intermediate, cooling, introducing olefin oxide, continuing the reaction after stopping introducing the olefin oxide until the pressure in the reaction kettle is reduced to a constant pressure, and aging and removing low-boiling-point substances to obtain the mixed phosphorus-containing polyol flame retardant. The invention has simple process, no pollution, mild reaction condition, high yield and low cost.)

1. A preparation method of a mixed phosphorus-containing polyol flame retardant is characterized by comprising the following steps:

1) putting a phosphorus-containing solvent into a reaction kettle, and adding N₂After replacing oxygen in the reaction kettle, adding phosphorus pentoxide into the reaction kettle, after the feeding is finished, heating the system in the reaction kettle to 90 ℃, stirring for 2-3 hours, and cooling the mixed system to room temperature;

2) adding an organic hydroxyl compound into the reaction kettle at a speed of 50-150 g/h to keep the temperature in the reaction kettle not higher than 60 ℃, and after the dropwise adding is finished, reacting for 2-6 h at a reaction temperature of 60-100 ℃ to obtain an intermediate;

3) when the intermediate is cooled to room temperature, introducing olefin oxide, and simultaneously controlling the pressure in the reaction kettle to slowly rise to maintain the final pressure of the reaction kettle at 0.01-0.2 MPa;

4) and (3) continuing the reaction after stopping introducing the olefin oxide until the pressure in the reaction kettle is reduced to a constant pressure, and aging for 2 hours to remove low-boiling-point substances to obtain the mixed phosphorus-containing polyol flame retardant.

2. The preparation method of the mixed phosphorus-containing polyol flame retardant as claimed in claim 1, wherein the feeding molar ratio of the phosphorus-containing solvent to the phosphorus pentoxide is 0.8-1.2: 1.

3. The method for preparing the mixed phosphorus-containing polyol flame retardant of claim 1 or 2, wherein the phosphorus-containing solvent is dimethyl methylphosphonate or diethyl ethylphosphonate.

4. The method for preparing the mixed phosphorus-containing polyol flame retardant of claim 1, wherein the feeding molar ratio of the phosphorus pentoxide to the organic hydroxyl compound is 1: 1-2.5.

5. The method for preparing the mixed type phosphorus-containing polyol flame retardant as claimed in claim 1 or 4, wherein the organic hydroxy compound is a mixture of a small molecular alcohol and a polyether polyol.

6. The preparation method of the mixed phosphorus-containing polyol flame retardant as claimed in claim 5, wherein the molar ratio of the small molecular alcohol to the polyether polyol is 1: 1-3.

7. The method for preparing the mixed phosphorus-containing polyol flame retardant of claim 5, wherein the small molecular alcohol is any one of ethanol, ethylene glycol, diethylene glycol, glycerol or trimethylolpropane.

8. The method for preparing the mixed phosphorus-containing polyol flame retardant of claim 5, wherein the polyether polyol is one or two of polyoxypropylene diol PPG-200, polyoxypropylene diol PPG-400 and polyoxypropylene triol N-303.

9. The method for preparing the mixed phosphorus-containing polyol flame retardant according to claim 1, wherein the mass of the alkylene oxide introduced is 70-90% of the mass of the intermediate.

10. The method of claim 1 or 9, wherein the alkylene oxide is ethylene oxide or propylene oxide.

Technical Field

The invention belongs to the technical field of production of flame retardant materials, and particularly relates to a production process of a mixed phosphonate flame retardant.

Background

The flame retardant is a special chemical auxiliary agent for improving the combustion performance of the combustible material. At present, the additive flame retardant containing halogen compounds is commonly used in the market, and can release corrosive and toxic gas when in use, pollute the environment and corrode equipment and harm the health of human bodies. The common halogen-free phosphorus phosphonate flame retardant has low phosphorus content, unobvious flame retardant effect and poor hydrolysis resistance and stability. Therefore, the halogen-free phosphorus-containing polyether polyol flame retardant with high flame retardance, high efficiency, hydrolysis resistance and environmental protection is the hot research at present. The phosphorus-containing polyether polyol is generally prepared from a phosphorus-containing compound, a small molecular alcohol and an alkylene oxide as raw materials.

Patent document CN 103204876 a discloses a preparation method of oligomeric organic phosphonate, which comprises the following preparation steps: (1) mixing DMMP and P₂O₅Reacting at 85-90 ℃; (2) cooling the reaction liquid obtained in the step (1) to 85-90 ℃, and adding an organic hydroxyl compound and trialkyl phosphite; (3) heating the reaction liquid obtained in the step (2) to 40-120 ℃ in a closed reaction kettle, introducing ethylene oxide, maintaining the pressure at 0.1-1.0 Mpa, and introducing the gas for 2-3 h; (4) when the hydroxyl value of the product is 130-150 mgKOH/g and the acid value is 5-25 mgKOH/g, the reaction is stopped to obtain the product.

Patent document CN 103554473 a discloses a method for preparing phosphorus-containing flame-retardant polyether polyol, which comprises the steps of firstly pouring phosphoric acid and phosphorus pentoxide into a reactor, then dripping ethylene glycol into the reactor for reaction and curing, and finally reacting ethylene oxide and propylene oxide to obtain the product.

Patent document CN 104829823 a discloses a method for preparing a phosphorus-containing flame-retardant polyol, which comprises heating phosphorus pentoxide and small molecular alcohol to obtain an intermediate, and continuously adding a catalyst and an epoxide to obtain the phosphorus-containing flame-retardant polyol.

Patent document CN 103467732 a discloses a method for preparing phosphorus-containing flame-retardant polyether polyol, which comprises reacting micromolecular alcohols with alkylene oxide under the action of a catalyst to obtain micromolecular polyether, mixing with a phosphorus-containing compound, reacting with the alkylene oxide under the action of the catalyst, neutralizing, dehydrating and refining to obtain the phosphorus-containing flame-retardant polyether polyol.

The phosphorus-containing flame-retardant polyether polyol preparation method disclosed by the above document mostly takes a phosphorylation reagent and small molecular alcohol as raw materials, and then alkylene oxide is introduced for chain extension. On one hand, the phosphorus-containing polyether polyol prepared by the method has a large acid value, and a part of tertiary amine catalyst can be neutralized in a prepared foam composition, so that the catalytic activity is reduced, and the foam structure is easy to collapse. On the other hand, the reaction of the raw material micromolecule alcohol and the olefin oxide can generate micromolecule aldehyde substances, which can cause heavy odor of products, and the foam used for polyurethane foaming has poor yellowing resistance, thereby influencing the use effect.

Disclosure of Invention

The invention aims to provide a preparation method of a mixed phosphorus-containing polyol flame retardant, which has the advantages of simple preparation process, no pollution, mild reaction conditions and high yield.

The invention comprises the following steps:

1) putting a phosphorus-containing solvent into a reaction kettle, and adding N₂After replacing oxygen in the reaction kettle, adding phosphorus pentoxide into the reaction kettle, after the feeding is finished, heating the system in the reaction kettle to 90 ℃, stirring for 2-3 hours, and cooling the mixed system to room temperature;

2) adding an organic hydroxyl compound into the reaction kettle at a speed of 50-150 g/h to keep the temperature in the reaction kettle not higher than 60 ℃, and after the dropwise adding is finished, reacting for 2-6 h at a reaction temperature of 60-100 ℃ to obtain an intermediate;

3) when the intermediate is cooled to room temperature, introducing olefin oxide, and simultaneously controlling the pressure in the reaction kettle to slowly rise to maintain the final pressure of the reaction kettle at 0.01-0.2 MPa;

4) and (3) continuing the reaction after stopping introducing the olefin oxide until the pressure in the reaction kettle is reduced to a constant pressure, and aging for 2 hours to remove low-boiling-point substances to obtain the mixed phosphorus-containing polyol flame retardant.

The invention has simple process, no pollution, mild reaction condition, high yield and low cost. The product prepared by the method has small acid value and peculiar smell, the foam foamed by polyurethane has good yellowing resistance and no peculiar smell, and the process has the advantages of adjustable phosphorus content and functionality of the product, can prepare phosphorus-containing polyether polyol flame retardants applied to different fields according to the requirements of customers, and has wide application range.

Preferably, the feeding molar ratio of the phosphorus-containing solvent to the phosphorus pentoxide is 0.8-1.2: 1.

The phosphorus-containing solvent is dimethyl methylphosphonate or diethyl ethylphosphonate.

The feeding molar ratio of the phosphorus pentoxide to the organic hydroxyl compound is 1: 1-2.5.

The organic hydroxyl compound is a mixture of micromolecular alcohol and polyether polyol.

The mole ratio of the micromolecule alcohol to the polyether polyol is 1: 1-3.

The organic hydroxyl compound adopted by the invention is a mixture of micromolecular alcohol and polyether polyol, so that on one hand, aldehyde micromolecules in the flame retardant can be reduced, and peculiar smell can be reduced; on the other hand, the chain length of the flame-retardant polyol can be adjusted to be short, and the chain rigidity and softness can be adjusted to prepare different types of phosphorus-containing flame-retardant polyols, so that the phosphorus-containing flame-retardant polyol can be applied to various fields.

The small molecular alcohol is any one of ethanol, ethylene glycol, diethylene glycol, glycerol or trimethylolpropane.

The polyether polyol is polyoxypropylene glycol PPG-200, polyoxypropylene glycol PPG-400 or polyoxypropylene triol N-303.

The mass of the introduced olefin oxide is 70-90% of the mass of the intermediate.

The alkylene oxide is ethylene oxide or propylene oxide.

The process has the beneficial effects that:

(1) the flame retardant disclosed by the invention is simple in preparation process, free of special equipment, pollution-free, mild in reaction condition, high in yield and low in cost.

(2) The flame retardant prepared by the method has small acid value and small smell, and is used for hard polyurethane foam, and the hard polyurethane foam has good yellowing resistance and no peculiar smell. Meanwhile, the functionality of the flame retardant is moderate (1-3), and the prepared body flame-retardant foam has good flexibility of hardness, thereby greatly expanding the application field of the flame retardant.

(3) The flame retardant produced by the process has the advantages of adjustable phosphorus content and functionality, wide application range and capability of preparing phosphorus-containing polyether polyol flame retardants applied to different fields according to customer requirements.

Detailed Description

Firstly, preparing a phosphorus-containing polyol flame retardant:

the present invention is further illustrated by the following examples, which should not be construed as limiting the scope of the invention as claimed.

Dimethyl methylphosphonate, diethyl ethylphosphonate, phosphorus pentoxide, ethanol, ethylene glycol, diethylene glycol, polyoxypropylene glycol (PPG-200 and PPG-400), glycerol, trimethylolpropane, polyoxypropylene triol (N-303), Ethylene Oxide (EO) and Propylene Oxide (PO) used in the examples of the present invention are all general technical grade products.

Comparative example 1:

refer to patent document CN 104829823 a.

Adding 142g of phosphorus pentoxide into the reaction kettle, starting stirring, adding 92g of ethanol, and stirring at 80 ℃ for 2 hours to obtain an intermediate. 2g of triethanolamine is continuously added, the temperature is kept at 120 ℃, 260g of ethylene oxide is added, and the reaction is carried out for 1 hour, 435g of product is obtained, the acid value is 14.8 mgKOH/g, and the hydroxyl value is 54 mgKOH/g.

Comparative example 2:

refer to patent document CN 103204876 a.

124g dimethyl methylphosphonate, N are added to the reaction kettle₂Purging to be oxygen-free, starting a circulating water cooling system, starting a stirrer, slowly adding 142g of phosphorus pentoxide into a reaction kettle, heating to 90 ℃, stirring for 3 hours, cooling to room temperature, slowly adding 124g of ethylene glycol, heating to 70 ℃, reacting for 3 hours, and adding 10g of trimethyl phosphite to obtain an intermediate.

Heating the intermediate to 80 ℃, slowly introducing ethylene oxide, controlling the pressure to slowly rise and keeping the pressure at 1.0MPa, introducing gas for 2h, metering and introducing 290g of ethylene oxide, stopping the reaction, and removing low-boiling-point substances to obtain 650g of product, wherein the acid value is 11.2 mgKOH/g, and the hydroxyl value is 78 mgKOH/g.

Example 1:

124g dimethyl methylphosphonate, N are added to the reaction kettle₂Purging to be oxygen-free, starting a circulating water cooling system, starting a stirrer, slowly adding 142g of phosphorus pentoxide into a reaction kettle, heating to 90 ℃, stirring for 3 hours, cooling to room temperature, slowly adding 46g of ethanol and 400g of polyoxypropylene glycol PPG-400 at the speed of 50-150 g/h, heating to 80 ℃, and reacting for 3 hours to obtain an intermediate.

After 712g of the intermediate is cooled to room temperature, 498g of ethylene oxide is slowly introduced, the pressure is controlled to slowly rise and is not higher than 0.1MPa, the temperature is controlled to be about 80 ℃, the reaction is continued after the feeding is finished, when the pressure is basically unchanged, the aging is carried out for 2h, and low-boiling-point substances are removed, 1185g of a product, the acid value is 3.2 mgKOH/g, and the hydroxyl value is 182 mgKOH/g is obtained.

Example 2:

166g of diethyl ethylphosphonate, N, were added to the reactor₂Purging to be oxygen-free, starting a circulating water cooling system, starting a stirrer, slowly adding 142g of phosphorus pentoxide into a reaction kettle, heating to 90 ℃, stirring for 3 hours, cooling to room temperature, slowly adding 46g of ethanol and 350g of polyoxypropylene triol N-303 at the speed of 50-150 g/h, heating to 90 ℃, and reacting for 3 hours to obtain an intermediate.

Cooling 704g of intermediate to room temperature, slowly introducing 490g of ethylene oxide, controlling the pressure to slowly rise and be not higher than 0.1MPa, controlling the temperature to be about 80 ℃, continuing the reaction after the feeding is finished, aging for 2h when the pressure is basically unchanged, and removing low-boiling-point substances to obtain 1190g of product, the acid value of 2.6 mgKOH/g and the hydroxyl value of 236 mgKOH/g.

Example 3:

100g of dimethyl methylphosphonate, N are added into a reaction kettle₂Purging to be anaerobic, starting a circulating water cooling system, starting a stirrer, slowly adding 142g of phosphorus pentoxide into the reaction kettle, then heating to 90 ℃, stirring for 3h, cooling to room temperature, slowly adding 53g of diethylene glycol and 200g of polypropylene oxide at the speed of 50-150 g/hAnd (3) heating the alkene glycol PPG-200 to 80 ℃ for reaction for 3h to obtain an intermediate.

When 495g of intermediate is cooled to room temperature, 366g of propylene oxide is slowly introduced, the pressure is controlled to slowly rise and is not higher than 0.1MPa, the temperature is controlled to be about 80 ℃, the reaction is continued after the addition of the materials is finished, when the pressure is basically unchanged, the aging is carried out for 2h, and low-boiling-point substances are removed, 842g of product, the acid value is 2.9 mgKOH/g, and the hydroxyl value is 259 mgKOH/g.

Example 4:

133g diethyl ethylphosphonate, N, were added to the reactor₂Purging to be oxygen-free, starting a circulating water cooling system, starting a stirrer, slowly adding 142g of phosphorus pentoxide into a reaction kettle, heating to 90 ℃, stirring for 3 hours, cooling to room temperature, slowly adding 31g of ethylene glycol and 350g of polyoxypropylene triol N-303 at the speed of 50-150 g/h, heating to 70 ℃, and reacting for 3 hours to obtain an intermediate.

Cooling 656g of intermediate to room temperature, slowly introducing 485g of propylene oxide, controlling the pressure to slowly rise and be not higher than 0.1MPa, controlling the temperature to be about 80 ℃, continuing the reaction after the feeding is finished, aging for 2h when the pressure is basically unchanged, and removing low-boiling-point substances to obtain 1120g of product, wherein the acid value is 2.4mgKOH/g, and the hydroxyl value is 321 mgKOH/g.

Example 5:

83g diethyl ethylphosphonate, N₂Purging to be oxygen-free, starting a circulating water cooling system, starting a stirrer, slowly adding 142g of phosphorus pentoxide into a reaction kettle, heating to 90 ℃, stirring for 3 hours, cooling to room temperature, slowly adding 72g of trimethylolpropane and 350g of polyoxypropylene triol N-303 at the speed of 50-150 g/h, heating to 70 ℃, and reacting for 3 hours to obtain an intermediate.

When 647g of intermediate is cooled to room temperature, 518g of ethylene oxide is slowly introduced, the pressure is controlled to slowly rise and is not higher than 0.1MPa, the temperature is controlled to be about 80 ℃, the reaction is continued after the addition is finished, when the pressure is basically unchanged, the aging is carried out for 2h, and low-boiling-point substances are removed, thus obtaining 1151g of product, the acid value is 1.4mgKOH/g, and the hydroxyl value is 384 mgKOH/g.

Example 6

62g of methylphosphonic acid bis (methylene phosphonic acid) are added into a reaction kettleMethyl ester, N₂Purging to be oxygen-free, starting a circulating water cooling system, starting a stirrer, slowly adding 142g of phosphorus pentoxide into a reaction kettle, heating to 90 ℃, stirring for 3 hours, cooling to room temperature, slowly adding 23g of ethanol, 100g of PPG-200 and 175g of polyoxypropylene triol N-303 at the speed of 50-150 g/h, heating to 80 ℃, and reacting for 3 hours to obtain an intermediate.

And cooling 502g of the intermediate to room temperature, slowly introducing 402g of propylene oxide, controlling the pressure to slowly rise and be not higher than 0.1MPa, controlling the temperature to be about 80 ℃, continuing the reaction after the addition is finished, aging for 2h when the pressure is basically unchanged, and removing low-boiling-point substances to obtain 898g of a product, wherein the acid value is 1.1mgKOH/g, and the hydroxyl value is 413 mgKOH/g.

Second, application example:

the application effect of the prepared flame retardant is inspected by preparing the flame retardant rigid polyurethane foam.

The flame retardants of the 2 comparative examples and 6 examples described above were in the white material component, respectively. And (3) electrically stirring and uniformly mixing the white material and the black material at the material temperature of 25 ℃, pouring the mixture into a mould for foaming to obtain 8 hard foam samples, curing for 72 hours, observing the application performance (appearance and cell structure) and measuring the flame retardant performance (limiting oxygen index LOI) of the hard foam samples.

The application performance of the sample is mainly to observe whether the sample has yellowing condition, whether the cell structure is uniform or not and whether the collapse phenomenon exists or not. The Limiting Oxygen Index (LOI) of the sample is measured by a JF-II type limiting oxygen index tester (Shanghai Zhongluo industry Co., Ltd.) according to GB/T2406-93 standard, and the sample size is 100 mm multiplied by 10 mm multiplied by 4 mm.

The test results are shown in the following table:

as can be seen from the product parameters and application results of the above examples and comparative examples, the acid value and hydroxyl value results of the product of the invention are superior to those of the comparative example, and the prepared flame-retardant rigid polyurethane foam has good yellowing resistance, uniform and non-collapsing foam cell structure and better flame-retardant effect.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the equivalent replacement or change according to the technical solution and the inventive concept should be covered by the scope of the present invention.