CN1563160A - Fire retardant in use for cellulose and fabricating method - Google Patents

Abstract

The invention relates to a flame retardant and a manufacturing method thereof. The designed molecular formula of the flame retardant for cellulose is C ₁₂ H ₂₆ O ₄ P ₂ S ₂ N ₂ , named 1,2-bis(2-thio- 5,5-Dimethyl-1,3,2-dioxaphosphorin-2-amino)ethane (DDPSN). Its production method is: firstly use the molar ratio of 1:1 phosphorous trichloride and neopentyl glycol to dissolve under the condition of temperature 45-75°C and benzene or pyridine whose mole number is 0.19-0.25 times the mole number of neopentyl glycol. , reacted for 1.5 to 3 hours, washed the product with water, and distilled off benzene, recrystallized with petroleum ether with 0.2 times the number of moles of benzene to generate DDSP, and then air-dried for 24 hours; then dried DDSP and ethylenediamine with a molar ratio of 2:1 Under the conditions of temperature 10-30°C and 0.1-0.15 moles of DDSP in chloroform or carbon tetrachloride, react for 3-5 hours, wash the product with water, and recrystallize with ether with 0.2 times the moles of chloroform or carbon tetrachloride , and then air-dried for 24 hours to generate the flame retardant DDPSN. The flame retardant of the invention is resistant to high temperature, resistant to water washing, has less addition amount, good flame retardant effect, high efficiency and environmental protection.

Description

A kind of flame retardant for cellulose and its preparation method

technical field

The invention relates to a flame retardant and its manufacturing method technology, specifically a flame retardant containing high-efficiency flame-retardant elements phosphorus, sulfur and nitrogen and specially used for cellulose and its derivative products and its manufacturing method technology. The patent classification number is proposed to be Int.Cl ⁷ C09D 7/12.

Background technique

Natural cellulose fiber is the earliest fiber used by humans, and viscose fiber is also the earliest chemical cellulose fiber used. Their comfortable and excellent performance is incomparable to other fibers, and they are widely favored by consumers. But whether it is natural cellulose fibers such as cotton and hemp, or chemical cellulose fibers such as viscose, all cellulose fibers have a biggest weakness, that is, they are flammable! Flammability limits the further development and wider application of cellulose fiber products, so developing cellulose fibers and their derivatives with good flame-retardant properties is an important research task. In fact, as early as the 1930s, durable fire retardants containing inorganic compounds of antimony and titanium had begun to be applied to the flame retardant treatment of cellulose fibers. Subsequently, Titanium Pigment successfully proposed DuPont's Erifon and Titanox FR and other flame-retardant finishing processes. In the 1960s, European and American countries competed to research and develop flame-retardant viscose fiber. After the 1970s, Lenzing developed a flame-retardant viscose fiber spun from Modal high-strength and high-wet modulus fibers. The flame retardant used was Sandoflam 5060. The fiber is blended with high-temperature-resistant aromatic polyamide fiber or wool, and the fabric can obtain a better flame-retardant effect; the American Avtex company has developed a flame-retardant viscose staple fiber with a positive oxygen phosphorus cyanide flame retardant Durvil, pajamas, bathrobes and blankets made of Durvil blended with an appropriate amount of Nomex fiber have good flame retardancy; the pollution-free flame-retardant polynosic fiber successfully developed by Japan Toyobo Co., Ltd. is A special phosphorus-based flame retardant is added to the spinning dope, and the oxygen index can reach 28-32. The fiber has the characteristics of high wet strength, good dimensional stability, and strong alkali resistance; Moscow, the former Soviet Union The flame-retardant ordinary viscose fiber used by the Textile Institute with methyl phosphoric acid diamide, when the phosphorus content reaches 2.1%, its oxygen index can also reach 28-33; the flame-retardant viscose fiber developed by the British Courtaulds company Asgard is a flame-retardant fiber made from viscose fabric impregnated with chemical solvents and then heat-treated to cause partial carbonization. Asgard fiber contains 5% carbon, and its oxygen index is as high as 50. It does not burn, melt, or shrink under flames, and has certain adsorption properties, but its tear strength is poor; the HFG fiber of Diwabo Corporation in Japan is made of Polychlorinated phosphonate flame retardant; Danufil CS flame retardant viscose fiber from Hoechst AG, Germany, the flame retardant is directly added to the spinning dope as finely dispersed particles , the oxygen index of the fiber is 27; in addition, the flame-retardant viscose fiber on the foreign market also has the permanent flame-retardant viscose fiber PER rayon (PER Rayon) in the United States; the permanent flame-retardant fiber of Avisco (Avisco) Viscose fiber; French Rhone Planck's flame-retardant viscose fiber TF80; in the 1990s, Abo Akadami of the Finnish Technology Research Center and Kemira Fabers of the textile manufacturing company Fibers) developed a flame-retardant viscose fiber with high silicon content called Visil. It is an organic/inorganic hybrid viscose fiber containing polysilicic acid, its oxygen index can reach more than 25, and it has excellent performance. It is a very good flame-retardant viscose fiber. British Courtaulds treated dry Lyocell fibers with tetravalent phosphide tetrakis hydroxymethylphosphorus-urea pre-concentrate to make flame-retardant Lyocell fibers.

Compared with foreign countries, the development of flame-retardant viscose fiber in my country is late, and the production capacity has not yet been formed, and the breadth and depth of development and application are far from enough. The industrial scale of domestic flame-retardant viscose fiber has explored the blending method and dip-coating method. The flame retardants used are mostly phosphorus-containing or halogen-containing organic compounds. Nanjing Chemical Fiber Company, Dandong Chemical Fiber Company, and Shanghai Chemical Fiber No. 3 Factory successively tested and produced flame-retardant viscose fiber products; Shanghai Textile Research Institute successfully synthesized STR-27 flame retardant (same structure as the aforementioned Sandoflam 5060) using domestic raw materials. And completed the development of flame-retardant viscose fiber, passed the small test appraisal of Shanghai Textile Bureau; and began to implement. In 2000, the Military Equipment Research Institute of the General Logistics Department and Beijing Institute of Technology jointly conducted research on flame retardant finishing of Lyocell fibers. The flame retardant used was THPC/urea initial shrinkage product of the British company Proban.

As mentioned above, there are many flame retardants for cellulose produced or researched at home and abroad, but most of the existing flame retardants for cellulose are halogen-containing flame retardants. It has good flame retardant effect. However, practice has proved that the halogen-containing flame retardants will produce toxic gases during the thermal decomposition process, thus causing serious environmental pollution problems. Therefore, the development of flame retardants for cellulose with low toxicity, halogen-free, environmental protection requirements and high efficiency has become a major research direction of countries all over the world. At present, there are also a small number of non-halogenated cellulose flame retardants, such as the STR-27 flame retardant successfully synthesized by the Shanghai Textile Research Institute and Sandoflam 5060, a similar foreign product. These two flame retardants have the same structure, are non-halogen flame retardants, contain phosphorus and sulfur elements, are phosphorus-sulfur composite flame retardants for cellulose, and are better among the existing cellulose flame retardants. . However, in the manufacturing process of flame-retardant cellulose products, the addition amount of flame retardants required in the prior art is relatively large (generally more than 20% of the cellulose weight, or higher, to meet the flame-retardant requirements), in order to obtain comparative The ideal flame retardant effect, the flame retardant efficiency is not high, and the product cost increases. At the same time, a large proportion of flame retardant addition will also reduce the original performance of the product, thus limiting the wide application of the flame retardant.

Contents of the invention

Aiming at the deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a kind of flame retardant with less added amount of flame retardant and good flame retardant effect, high-efficiency and environment-friendly flame retardant for cellulose; The method has the characteristics of simple process, low cost, easy industrial implementation and the like.

The technical solution of the present invention to solve the technical problem of the flame retardant product is: to design a flame retardant for cellulose, its molecular formula is C ₁₂ H ₂₆ O ₄ P ₂ S ₂ N ₂ , and its chemical structural formula is:

Named 1,2-bis(2-thio-5,5-dimethyl-1,3,2-dioxaphosphorin-2-amino)ethane (DDPSN).

The technical solution of the present invention to solve the technical problems of the flame retardant manufacturing method is: first use thion trichloride (PSCl ₃ ) and neopentyl glycol with a molar ratio of 1:1 at a temperature of 45-75° C. Under the condition that 0.19-0.25 times the number of moles of pentanediol is dissolved in benzene or pyridine, react for 1.5-3 hours, then wash the obtained product with water, distill off benzene, and recrystallize with petroleum ether with 0.2 times the number of moles of benzene to generate 2 - Thio-2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane (DDSP), then air-dried for 24h; Ethylenediamine is reacted for 3-5 hours at a temperature of 10-30°C and 0.1-0.15 moles of DDSP moles in chloroform or carbon tetrachloride are dissolved. Several ether recrystallizations, and then air-drying for 24 hours, can generate the flame retardant: 1,2-bis(2-thio-5,5-dimethyl-1,3,2-dioxaphospha Cyclohexa-2-amino)ethane (DDPSN).

The melting point of the flame retardant for cellulose of the present invention is 291-292°C, which is higher than the melting point of general flame retardants for cellulose (such as the melting point of Sandoflam 5060 is 228-229°C). , can withstand temperatures above 300°C, and has the characteristics of high temperature resistance. Because it contains three elements with high flame retardancy: phosphorus, sulfur and nitrogen, and all of them can chemically interact with the hydroxyl groups of cellulose, and the combination is firm. The flame retardant effect is stronger and longer lasting, and due to the synergistic effect of phosphorus-nitrogen and phosphorus-sulfur, it can greatly enhance the flame retardant performance of flame retardants on cellulose, and is an efficient and durable flame retardant. Combustion tests show that when the content of the flame retardant of the present invention is 20% in the cellulose, its limiting oxygen index can be as high as 32, and it has a good flame retardant effect. The flame retardant of the present invention is washable because it will not be dissolved by water. This shows that the flame retardant of the present invention can still maintain its flame retardant function even when rescued with water, thereby strengthening its flame retardant effect and prolonging its flame retardant time. At the same time, the flame retardant of the present invention is also slightly soluble in general organic solvents, such as ethanol, acetone, chloroform, carbon tetrachloride and acetonitrile, etc., which can also enhance its flame retardant effect and prolong its flame retardant time.

Description of drawings

Fig. 1 is the synthetic route schematic diagram of flame retardant DDPSN of the present invention;

Fig. 2 is the thermogravimetry-differential heat (TG-DTA) analysis figure of flame retardant DDPSN of the present invention;

Fig. 3 is the differential scanning calorimetry (DSC) analysis curve of flame retardant DDPSN of the present invention;

Fig. 4 is the infrared spectrum (IR) analysis spectrogram of flame retardant DDPSN of the present invention;

Fig. 5 is the nuclear magnetic resonance ( ^1HNMR ) analysis spectrogram of flame retardant DDPSN of the present invention;

Fig. 6 is a mass spectrometry (MS) analysis spectrum of the flame retardant DDPSN of the present invention.

Detailed ways

Further describe the present invention below in conjunction with embodiment and accompanying drawing:

The flame retardant for cellulose of the present invention has a molecular formula of C ₁₂ H ₂₆ O ₄ P ₂ S ₂ N ₂ and a chemical structural formula of:

It can be named as 1,2-bis(2-thio-5,5-dimethyl-1,3,2-dioxaphosphorin-2-amino)ethane (DDPSN). In the structural formula of the flame retardant, it can be clearly seen that there are three highly efficient flame retardant elements phosphorus, sulfur and nitrogen, and phosphorus and sulfur, phosphorus and nitrogen exist in the flame retardant in the form of stable chemical bonds. Their simultaneous existence and mutual synergy can greatly improve the flame retardant effect of the flame retardant, and have the characteristics of high temperature resistance.

The present invention simultaneously designs the manufacture method of flame retardant DDPSN. The method comprises the following two synthesis steps (referring to Fig. 1): at first with the molar ratio of 1: 1 phosphorus trichloride (PSCl ₃ ) and neopentyl glycol at a temperature of 45 ~ 75 ° C and the number of moles is neopentyl glycol Under the condition of 0.19-0.25 moles of benzene or pyridine dissolved, react for 1.5-3 hours, then wash the obtained product with water, distill off benzene, and then recrystallize with 0.2 moles of benzene in petroleum ether to generate 2-thio -2-Chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane (DDSP), then air-dried for 24 hours; Under the conditions of temperature 10-30°C and 0.1-0.15 moles of DDSP moles in chloroform or carbon tetrachloride dissolved, react for 3-5 hours, wash the obtained product with water, and then use 0.2 times the moles of chloroform or carbon tetrachloride in ether Recrystallization, then air-drying 24h, can generate described flame retardant: 1,2-bis(2-thio-5,5-dimethyl-1,3,2-dioxaphosphine- 2-amino)ethane (DDPSN).

The concrete technological process of the inventive method is as follows:

(1) Synthesis of PSCl ₃ . Add 1 mole of sulfur and 0.015 mole of aluminum trichloride to a four-necked flask equipped with a thermometer, agitator, and reflux condenser, and heat up to 115°C to melt the sulfur; 1 mole of PCl ₃ was quickly added to the four-necked flask, the temperature was controlled at 145° C., and the reaction was carried out for 1 hour. Finally, the reaction solution was distilled, and the fraction between 120°C was taken to obtain a colorless and transparent liquid, namely PSCl ₃ . PSCl ₃ is a kind of intermediate of herbicide pesticide, is a kind of known technology, is not essential content of the present invention. This synthetic procedure is not necessary when a commercially available product is available.

(2) Synthesis of DDSP. Add 0.24 moles of phosphorous trichloride PSCl ₃ and 0.24 moles of neopentyl glycol into a four-necked flask equipped with a thermometer, stirrer, and reflux condenser, then add 0.05 to 0.06 moles of benzene, and heat up to 50°C to make neopentyl glycol Dissolve the diol, then slowly add 0.05-0.06 mole of pyridine dropwise into the four-neck flask with a dropping funnel, control the temperature between 45-75°C, and react at a constant temperature for 1.5-3 hours. After the reaction, add 30ml of distilled water, shake well and filter to separate the oil layer, and distill off benzene, and finally recrystallize the product with 0.1-0.12 moles of petroleum ether to obtain a white semi-crystalline solid, which is 2-thio-2-chloro-5, 5-Dimethyl-1,3,2-dioxaphosphorinane (DDSP);

(3) Synthesize DDPSN. After drying the obtained DDSP, take 0.2 moles and add it to the same reaction device, add 0.02-0.03 moles of chloroform or CCl ₄ , control the reaction temperature at 10-30°C, slowly add 0.1 moles of ethylenediamine, and the reaction time is 3 hours. Wash the reaction product with water after stopping, and recrystallize with 0.04-0.06 mole of ether to obtain a white powdery solid, which is the flame retardant produced by the present invention: 1,2-bis(2-thio-5,5-dimethyl -1,3,2-dioxaphosphorin-2-amino)ethane (DDPSN).

In the first step PSCl described in the inventive method ₃ synthetic process, because the synthetic of PSCl ₃ is carried out under high temperature condition, sulfur is easily subjected to thermal oxidation at high temperature and generates sulfur dioxide (SO ₂ ), so that actually participate in reaction sulfur In addition, when adding PCl ₃ , because it is a very violent exothermic reaction, the temperature in the reaction bottle rises sharply, the reaction temperature is difficult to control, and a large amount of PCl that has not had time to react _escapes . Into the air, also cause the ratio change of the amount between the reactant, and also be difficult to measure, these factors not only influence product yield, and also can have influence on the performance of product _PSCl3 . Considering the adverse effects of these factors on the synthesis reaction, the further feature of the method of the present invention is that nitrogen is selected as the protective gas during the entire synthesis process of the flame retardant, and the by-product hydrogen chloride gas (HCl) of the reaction is excluded. In the first step of the synthesis process, while nitrogen is used as a protective gas, the addition rate of PCl ₃ must also be controlled. It is required to add PCl ₃ slowly and stir evenly, so that the reaction can be carried out completely, the exothermic situation is mild, and the reaction is easier to control. , The yield of the reaction product PSCl ₃ is high, and it is easy to crystallize purely. In the same way, in the synthesis of the second step DDSP and the third step DDPSN, the method of passing nitrogen gas is also adopted, because in these two steps of reaction, hydrogen chloride (HCl) gas will also be produced, and the feeding of nitrogen gas is conducive to the formation of HCl gas. Discharge makes the reaction develop towards the positive direction, which is beneficial to the formation of the product. In addition, considering that in the synthesis of DDSP, a large amount of hydrogen chloride gas needs to be discharged, the method of adding fuacid agent pyridine can be used in the process to capture the by-product HCl gas, which is beneficial to the elimination of HCl gas. For the same reason, the addition of pyridine also requires slow and uniform dropwise addition. If pyridine is added too quickly, pyridine will react with HCl gas too quickly, and the generated pyridine salt will adhere to the wall of the reaction bottle, which is unfavorable for the normal progress of the reaction.

The flame retardant DDPSN of the present invention synthesized by the manufacturing method of the present invention has been further analyzed and studied as follows:

The analysis of the flame retardant of the present invention shows (see Fig. 3) that the melting point of the flame retardant DDPSN is 292-293° C., indicating that the flame retardant can withstand higher temperatures in the process of thermal decomposition, and can be used at higher temperatures. play a role in flame retardancy.

Analysis of Figure 2 shows that the flame retardant of the present invention begins to decompose at 110°C; during the period of 120-220°C, the weight loss is the fastest, and the weight loss can reach 60%; when it reaches 800°C, the weight loss is as high as 98%, and it is almost completely decomposed. A large amount of gas and volatile substances are generated in the weight loss, indicating that the flame retardant is mainly gas-phase flame retardant. It can also be seen from the DTA curve that the flame retardant of the present invention has a small melting endothermic peak at 120 ° C, and a decomposition exothermic peak at 158 ° C, which is in a relatively fast weight loss area, which is caused by decomposition to generate volatile substances; 210 There is a large endothermic decomposition peak at ℃, indicating that the flame retardant can decompose quickly and release a large amount of gas. The endothermic peak at 210°C just falls in the fastest weight loss area of the flame retardant, which is caused by the large amount of heat that is taken away when a large amount of gas is volatilized. It shows that the flame retardant can be thermally decomposed before the cellulose during the heating process, releasing a flame retardant gas, thereby blocking the contact of cellulose with oxygen and fire source, and playing a good flame retardant effect.

Further analysis shows (see Figure 4), 2972.52cm ^-1 is CH stretching vibration of -CH ₃ group, 3200～3500cm ^-1 is stretching vibration of NH, 1473.91cm ^-1 is bending vibration of -CH ₂ group, 1372.44 cm ^-1 is the bending vibration of CH.

From ^{the 1} HNMR chart (see Figure 5), it can be seen that the chemical shift of the -CH ₃ group is 0.89547 to 0.92098 ppm; the chemical shift of the -CH ₂ group is around 1.31216 ppm; the chemical shift of the -NH group is about 2.9 to 3.5 between; the chemical shift between 3.84295-4.03894ppm may be one of the -CH ₂ O groups, and the chemical shift of the other -CH ₂ O group may fall between 4.23261-4.30474ppm. In this compound, the chemical shifts of the two -CH ₂ O groups are difficult to distinguish due to the optical isomerism of the -CH ₂ O groups.

From the analysis of the mass spectrogram MS (see Figure 6), it can be seen that the relative molecular mass of the compound is 388.3, which is consistent with the expected molecular weight. There is a small peak near m/z 388.3, which is caused by the fragment peak generated by the isotope; m/z=30 is the CH ₂ O peak, and m/z=41.1 is the fragment corresponding to the C ₂ H ₂ O group Peak; m/z=69.1 is the fragment peak of C ₅ H ₁₀ group; m/z=133.1 is the fragment peak of C ₅ H ₁₀ O ₂ P group, m/z=167.5 is the fragment peak of C ₅ H ₁₀ O ₂ PS The fragment peak of the group, m/z=182.2 is the fragment peak of the C ₅ H ₁₁ O ₂ PSN group. Many other fragment peaks can also be seen from the MS diagram, which indicate the presence of isotopic elements such as P and S contained in the compound.

Through the above research and analysis, it can be seen that the synthesized flame retardant has the same structure as the flame retardant DDPSN designed for cellulose in the present invention. When the content of the flame retardant in the present invention is 20% in the cellulose, its limiting oxygen index can be as high as 29, fully meeting the flame retardant standard.

Tests show that the flame retardant for cellulose of the present invention is insoluble in water, so it can be washed with water, and it is also insoluble in organic solvents such as ethanol, acetone, chloroform, carbon tetrachloride, and acetonitrile. This shows that even when rescued with water or the organic solvent, the flame retardant of the present invention can still maintain its flame retardant function, thereby strengthening its flame retardant effect and prolonging its flame retardant time, and has good flame retardant function or Effect.

The flame retardant for cellulose of the present invention is suitable for the flame retardant requirements of various cellulose and its derivative products (such as fibers, plastics, fabrics, non-woven fabrics, etc.).

The flame retardant of the invention can be used as a flame retardant additive component in the manufacturing process of various cellulose and its derivative products, and the added amount of the flame retardant is 15-30% of the weight of the cellulose or its derivative products.

The flame retardant of the invention can be used as a flame retardant additive component of the paint and is specially used in the coating process of various cellulose and its derivative products, and the flame retardant concentration of the paint solution is 5-30%.

Provide specific embodiment below, the present invention is described further:

Example 1:

(1) Synthesis of PSCl ₃

Add 1 mole of sulfur and 0.015 mole of aluminum trichloride to a four-necked flask equipped with a thermometer, agitator, and reflux condenser, and heat up to 115°C to melt the sulfur; 1 mole of PCl ₃ was quickly added to the four-necked flask, the temperature was controlled at 145° C., and the reaction was carried out for 1 hour. Finally, the reaction solution was distilled, and the fraction between 120°C was taken to obtain a colorless and transparent liquid, which was PSCl ₃ ;

(2) Synthesis of 2-thio-2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane (DDSP)

Add 0.24 moles of _PSCl and 0.24 moles of neopentyl glycol to a four-necked flask equipped with a thermometer, agitator, and reflux condenser, then add 0.05 moles of benzene, heat up to 50°C to dissolve neopentyl glycol, and then control The temperature was 45°C, and the reaction was carried out at constant temperature for 1.5h. After the reaction, add 30ml of distilled water, shake well and filter to separate the oil layer, and distill off benzene, and finally recrystallize the product with 0.1 mole of petroleum ether to obtain a white semi-crystalline solid, which is 2-thio-2-chloro-5,5- Dimethyl-1,3,2-dioxaphosphorinane (DDSP);

(3) Synthesis of 1,2-bis(2-thio-5,5-dimethyl-1,3,2-dioxaphosphorin-2-amino)ethane (DDPSN)

Put 1 mole of DDSP after drying into a four-neck flask equipped with a thermometer, a stirrer, and a reflux condenser, add 0.1 mole of CCl ₄ , control the reaction temperature at 10°C, and slowly add 0.5 mole of ethylenediamine. The reaction time is After 1.5h, the reaction product was washed with water after the reaction was stopped, and recrystallized with 0.2 mole of ether to obtain a white powdery solid, which was the flame retardant produced by the present invention: 1,2-bis(2-thio-5,5- Dimethyl-1,3,2-dioxaphosphorin-2-amino)ethane (DDPSN).

Example 2:

(1) Synthesis of PSCl ₃

With embodiment 1;

(2) Synthesis of DDSP

Add 0.24 moles of PSCl ₃ and 0.24 moles of neopentyl glycol to a four-necked flask equipped with a thermometer, a stirrer, and a reflux condenser, then add 0.055 moles of benzene, heat up to 50°C to dissolve the neopentyl glycol, and then control The temperature was 75°C, and the reaction was performed at a constant temperature for 3 hours. After the reaction, add 30ml of distilled water, shake well and filter to separate the oil layer, and distill off benzene, and finally recrystallize the product with 0.15 mole of petroleum ether to obtain a white semi-crystalline solid, which is DDSP;

(3) Synthesis of DDPSN

Put 1 mole of DDSP after drying into a four-necked flask equipped with a thermometer, a stirrer, and a reflux condenser, add 0.1 mole of CCl ₄ , control the reaction temperature at 30°C, and slowly add 0.5 mole of ethylenediamine. The reaction time is After 3 hours, the reaction product was washed with water and recrystallized with 0.2 mole of ether to obtain a white powdery solid, which was the flame retardant produced by the present invention: DDPSN.

Example 3:

(1) Synthesis of PSCl ₃

With embodiment 1;

(2) Synthesis of DDSP

Add 0.24 moles of _PSCl and 0.24 moles of neopentyl glycol to a four-necked flask equipped with a thermometer, agitator, and reflux condenser, then add 0.05 moles of benzene, heat up to 50°C to dissolve neopentyl glycol, and then control The temperature was 60°C, and the reaction was carried out at a constant temperature for 2.5 hours. After the reaction, add 30ml of distilled water, shake and filter to separate the oil layer, and distill to remove benzene, and finally recrystallize the product with 0.12 moles of petroleum ether to obtain a white semi-crystalline solid, which is DDSP;

(3) Synthesis of DDPSN

Put 1 mole of DDSP after drying into a four-necked flask equipped with a thermometer, a stirrer, and a reflux condenser, add 0.1 mole of CCl ₄ , control the reaction temperature at 25°C, and slowly add 0.5 mole of ethylenediamine. The reaction time is After 3 hours, the reaction product was washed with water and recrystallized with 0.2 mole of ether to obtain a white powdery solid, which was the flame retardant produced by the present invention: DDPSN.

Example 4:

(1) Synthesis of PSCl ₃

With embodiment 1;

(2) Synthesis of DDSP

Add 0.24 moles of _PSCl and 0.24 moles of neopentyl glycol to a four-necked flask equipped with a thermometer, agitator, and reflux condenser, then add 0.06 moles of benzene, heat up to 50°C to dissolve the neopentyl glycol, and then control The temperature was 55°C, and the reaction was carried out at constant temperature for 2.5 hours. After the reaction, add 30ml of distilled water, shake well and filter to separate the oil layer, and distill off benzene, and finally recrystallize the product with 0.15 mole of petroleum ether to obtain a white semi-crystalline solid, which is DDSP;

(3) Synthesis of DDPSN

Put 1 mole of DDSP after drying into a four-necked flask equipped with a thermometer, agitator and reflux condenser, add 0.1 mole of CCl ₄ , control the reaction temperature at 20°C, slowly add 0.5 mole of ethylenediamine, and the reaction time is After 3 hours, the reaction product was washed with water and recrystallized with 0.2 mole of ether to obtain a white powdery solid, which was the flame retardant produced by the present invention: DDPSN.

Example 5:

(1) Synthesis of PSCl ₃

With embodiment 1;

(2) Synthesis of DDSP

Add 0.24 moles of PSCl ₃ and 0.24 moles of neopentyl glycol to a four-necked flask equipped with a thermometer, stirrer, and reflux condenser, then add 0.058 moles of benzene, heat up to 50°C to dissolve the neopentyl glycol, and then control The temperature was 50°C, and the reaction was performed at a constant temperature for 2 hours. After the reaction, add 30ml of distilled water, shake and filter to separate the oil layer, and distill to remove benzene, and finally recrystallize the product with 0.12 moles of petroleum ether to obtain a white semi-crystalline solid, which is DDSP;

(3) Synthesis of DDPSN

Put 1 mole of DDSP after drying into a four-necked flask equipped with a thermometer, agitator and reflux condenser, add 0.1 mole of CCl ₄ , control the reaction temperature at 20°C, slowly add 0.5 mole of ethylenediamine, and the reaction time is After 2 hours, the reaction product was washed with water and recrystallized with 0.2 mole of ether to obtain a white powdery solid, which was the flame retardant produced by the present invention: DDPSN.

Embodiment 6:

(1) Synthesis of PSCl ₃

With embodiment 1;

(2) Synthesis of DDSP

Add 0.24 moles of PSCl ₃ and 0.24 moles of neopentyl glycol to a four-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen inlet pipe, then add 0.055 moles of benzene, and heat up to 50°C to make the neopentyl glycol Dissolve, then control the temperature at 45°C, and react at a constant temperature for 1.5h. After the reaction, add 30ml of distilled water, shake well and filter to separate the oil layer, and distill off benzene, and finally recrystallize the product with 0.1 mole of petroleum ether to obtain a white semi-crystalline solid, which is DDSP;

(3) Synthesis of DDPSN

Put the dried 1 mole of DDSP into a four-neck flask equipped with a thermometer, a stirrer, and a reflux condenser nitrogen inlet tube, add 0.1 mole of CCl ₄ , control the reaction temperature at 10°C, and slowly add 0.5 mole of ethylenediamine, The reaction time is 1.5 hours. After the reaction is stopped, the reaction product is washed with water and recrystallized with 0.2 mole of ether to obtain a white powdery solid, which is the flame retardant produced by the present invention: DDPSN.

Embodiment 7:

(1) Synthesis of PSCl ₃

With embodiment 1;

(2) Synthesis of DDSP

Add 0.24 moles of PSCl ₃ and 0.24 moles of neopentyl glycol to a four-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen inlet pipe, then add 0.05 moles of benzene, and heat up to 50°C to make the neopentyl glycol Dissolve, then control the temperature at 45°C, and react at a constant temperature for 3h. After the reaction, add 30ml of distilled water, shake and filter to separate the oil layer, and distill to remove benzene, and finally recrystallize the product with 0.12 moles of petroleum ether to obtain a white semi-crystalline solid, which is DDSP;

(3) Synthesis of DDPSN

Put the dried 1 mole of DDSP into a four-neck flask equipped with a thermometer, a stirrer, and a reflux condenser nitrogen inlet tube, add 0.1 mole of CCl ₄ , control the reaction temperature at 10°C, and slowly add 0.5 mole of ethylenediamine, The reaction time is 3 hours. After the reaction is stopped, the reaction product is washed with water and recrystallized with 0.2 mole of ether to obtain a white powdery solid, which is the flame retardant produced by the present invention: DDPSN.

Embodiment 8:

(1) Synthesis of PSCl ₃

With embodiment 1;

(2) Synthesis of DDSP

Add 0.24 moles of PSCl ₃ and 0.24 moles of neopentyl glycol to a four-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen inlet pipe, then add 0.055 moles of benzene, and heat up to 50°C to make the neopentyl glycol Dissolve, then control the temperature at 75°C, and react at a constant temperature for 1.5h. After the reaction, add 30ml of distilled water, shake well and filter to separate the oil layer, and distill off benzene, and finally recrystallize the product with 0.15 mole of petroleum ether to obtain a white semi-crystalline solid, which is DDSP;

(3) Synthesis of DDPSN

Put the dried 1 mole of DDSP into a four-neck flask equipped with a thermometer, a stirrer, and a reflux condenser nitrogen inlet tube, add 0.1 mole of CCl ₄ , control the reaction temperature at 30°C, and slowly add 0.5 mole of ethylenediamine, The reaction time is 1.5 hours. After the reaction is stopped, the reaction product is washed with water and recrystallized with 0.2 mole of ether to obtain a white powdery solid, which is the flame retardant produced by the present invention: DDPSN.

Embodiment 9:

(1) Synthesis of PSCl ₃

With embodiment 1;

(2) Synthesis of DDSP Add 0.24 moles of PSCl and _0.24 moles of neopentyl glycol in a four-necked flask equipped with a thermometer, stirrer, reflux condenser, and nitrogen inlet pipe, then add 0.058 moles of benzene, and heat up to 50 ℃ to dissolve the neopentyl glycol, and then control the temperature at 55 ℃ for a constant temperature reaction for 2 hours. After the reaction, add 30ml of distilled water, shake and filter to separate the oil layer, and distill to remove benzene, and finally recrystallize the product with 0.18 mole of petroleum ether to obtain a white semi-crystalline solid, which is DDSP;

(3) Synthesis of DDPSN

Put 1 mole of DDSP after drying into a four-neck flask equipped with a thermometer, a stirrer, and a reflux condenser nitrogen inlet tube, add 0.1 mole of CCl ₄ , control the reaction temperature at 25°C, and slowly add 0.5 mole of ethylenediamine, The reaction time is 2 hours. After the reaction is stopped, the reaction product is washed with water and recrystallized with 0.2 mole of ether to obtain a white powdery solid, which is the flame retardant produced by the present invention: DDPSN.

Example 10:

(1) Synthesis of PSCl ₃

With embodiment 1;

(2) Synthesis of DDSP

Add 0.24 moles of PSCl ₃ and 0.24 moles of neopentyl glycol to a four-necked flask equipped with a thermometer, stirrer, reflux condenser, and nitrogen inlet pipe, then add 0.06 moles of benzene, heat up to 50 ° C to make the neopentyl glycol Dissolve, and then dropwise add 0.06 mol of pyridine into the four-neck flask with a dropping funnel, control the temperature at 45°C, and react at a constant temperature for 1.5h. After the reaction, add 30ml of distilled water, shake well and filter to separate the oil layer, and distill off benzene, and finally recrystallize the product with 0.15 mole of petroleum ether to obtain a white semi-crystalline solid, which is DDSP;

(3) Synthesis of DDPSN

Put 1 mole of DDSP after drying into a four-neck flask equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen inlet pipe, add 0.1 mole of CCl ₄ , control the reaction temperature at 10°C, and slowly add 0.5 mole of ethylenediamine , The reaction time is 1.5h. After the reaction is stopped, the reaction product is washed with water and recrystallized with 0.2 mole of ether to obtain a white powdery solid, which is the flame retardant produced by the present invention: DDPSN.

Example 11:

(1) Synthesis of PSCl ₃

With embodiment 1;

(2) Synthesis of DDSP

Add 0.24 moles of PSCl ₃ and 0.24 moles of neopentyl glycol to a four-necked flask equipped with a thermometer, stirrer, reflux condenser, and nitrogen inlet pipe, then add 0.06 moles of benzene, heat up to 50 ° C to make the neopentyl glycol Dissolve, and then dropwise add 0.055 mol of pyridine into the four-neck flask with a dropping funnel, control the temperature at 45°C, and react at a constant temperature for 3 hours. After the reaction, add 30ml of distilled water, shake well and filter to separate the oil layer, and distill off benzene, and finally recrystallize the product with 0.1-0.12 moles of petroleum ether to obtain a white semi-crystalline solid, which is DDSP;

(3) Synthesis of DDPSN

Put 1 mole of DDSP after drying into a four-neck flask equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen inlet pipe, add 0.1 mole of CCl ₄ , control the reaction temperature at 10°C, and slowly add 0.5 mole of ethylenediamine , The reaction time is 3h. After the reaction is stopped, the reaction product is washed with water and recrystallized with 0.2 mole of ether to obtain a white powdery solid, which is the flame retardant produced by the present invention: DDPSN.

Example 12:

(1) Synthesis of PSCl ₃

With embodiment 1;

(2) Synthesis of DDSP

Add 0.24 moles of PSCl ₃ and 0.24 moles of neopentyl glycol to a four-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen inlet pipe, then add 0.05 moles of benzene, and heat up to 50°C to make the neopentyl glycol Dissolve, and then dropwise add 0.06 mol of pyridine to the four-neck flask with a dropping funnel, control the temperature at 75°C, and react at a constant temperature for 1 hour. After the reaction, add 30ml of distilled water, shake and filter to separate the oil layer, and distill to remove benzene, and finally recrystallize the product with 0.12 moles of petroleum ether to obtain a white semi-crystalline solid, which is DDSP;

(3) Synthesis of DDPSN

Put 1 mole of DDSP after drying into a four-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen inlet pipe, add 0.1 mole of CCl ₄ , control the reaction temperature at 30°C, and slowly add 0.5 mole of ethylenediamine , The reaction time is 2h. After the reaction is stopped, the reaction product is washed with water and recrystallized with 0.2 mole of ether to obtain a white powdery solid, which is the flame retardant produced by the present invention: DDPSN.

Example 13:

(1) Synthesis of PSCl ₃

With embodiment 1;

(2) Synthesis of DDSP

Add 0.24 moles of PSCl ₃ and 0.24 moles of neopentyl glycol to a four-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen inlet pipe, then add 0.05 moles of benzene, and heat up to 50°C to make the neopentyl glycol Dissolve, and then dropwise add 0.05 mole of pyridine to the four-neck flask with a dropping funnel, control the temperature at 45°C, and react at a constant temperature for 1.5h. After the reaction, add 30ml of distilled water, shake well and filter to separate the oil layer, and distill off benzene, and finally recrystallize the product with 0.1 mole of petroleum ether to obtain a white semi-crystalline solid, which is DDSP;

(3) Synthesis of DDPSN

Put 1 mole of DDSP after drying into a four-neck flask equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen inlet pipe, add 0.1 mole of chloroform or CCl ₄ , control the reaction temperature at 10°C, and slowly add 0.5 mole of ethyl alcohol. Diamine, the reaction time is 2h, after the reaction is stopped, the reaction product is washed with water, and recrystallized with 0.2 mole of ether to obtain a white powdery solid, which is the flame retardant produced by the present invention: 1,2-bis(2-sulfur Dioxa-5,5-dimethyl-1,3,2-dioxaphosphorin-2-amino)ethane (DDPSN).

Example 14:

Example 14 is basically the same as Example 13, with the difference that: in the third step of synthesizing DDPSN, _0.15 mol of CCl is used, the reaction temperature is 20° C., the reaction time is 3 h, and the solvent diethyl ether used for recrystallization is 0.3 mol.

Claims (5)

1. A flame retardant for cellulose, its molecular formula is C ₁₂ H ₂₆ O ₄ P ₂ S ₂ N ₂ , and its chemical structural formula is: Named 1,2-bis(2-thio-5,5-dimethyl-1,3,2-dioxaphosphorin-2-amino)ethane (DDPSN), 2. The flame retardant for cellulose according to claim 1, characterized in that the flame retardant has a melting point of 291-292°C, is insoluble in water and slightly soluble in ethanol, acetone, chloroform, carbon tetrachloride and ethyl alcohol. organic solvents such as eyeglass. 3. a kind of manufacture method of flame retardant for cellulose as claimed in claim 1, first use mol ratio as 1: 1 phosphorus trichloride (PSCl ₃ ) and neopentyl glycol at temperature 45～75 ℃ with mole Under the condition that 0.19 to 0.25 times the number of moles of neopentyl glycol is dissolved in benzene or pyridine, react for 1.5 to 3 hours, then wash the product with water, distill off benzene, and recrystallize with petroleum ether with 0.2 times the number of moles of benzene , to generate 2-thio-2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane (DDSP), then air-dried for 24h; then dried with a molar ratio of 2:1 DDSP and ethylenediamine are reacted for 3 to 5 hours at a temperature of 10 to 30°C and 0.1 to 0.15 moles of DDSP moles in chloroform or carbon tetrachloride are dissolved, and the resulting product is washed with water, and then washed with 0.2 times chloroform or tetrachloride Diethyl ether recrystallization of carbonized moles, and then air-drying for 24 hours, can generate the described flame retardant: 1,2-bis(2-thio-5,5-dimethyl-1,3,2-bis Oxaphosphorin-2-amino)ethane (DDPSN). 4. according to the manufacture method of the described flame retardant for cellulose of claim 3, it is characterized in that this method selects nitrogen to make protective gas in the whole synthesis process of described flame retardant, and the by-product hydrogen chloride gas of getting rid of reaction. 5. according to the manufacture method of the described flame retardant for cellulose of claim 3, it is characterized in that this method selects pyridine to make acid agent in the whole synthesis process of described flame retardant, captures reaction by-product hydrogen chloride gas.

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