阅读说明：本技术 一种氮磷协效阻燃剂改性纤维素薄膜材料及制备方法 (Nitrogen-phosphorus synergistic flame retardant modified cellulose film material and preparation method thereof ) 是由 胡晓强 于 2020-12-01 设计创作，主要内容包括：本发明涉及阻燃材料技术领域,且公开了一种氮磷协效阻燃剂改性纤维素薄膜材料,对苯二胺、甲醛和亚磷酸发生Mannich反应,再与尿素生成N,N-二亚甲基苯基磷酸铵盐,作为氮磷协效阻燃剂,然后在双氰胺的催化作用下,其铵根离子与纤维素的羟基发生取代反应,得到氮磷协效阻燃剂接枝改性的N,N-二亚甲基苯基磷酸酯基纤维素,进一步塑化和成膜,得到氮磷协效阻燃剂改性纤维素薄膜材料,通过化学共价接枝,将氮磷协效阻燃剂引入纤维素的基体中,使阻燃剂高度分散在纤维素膜基体中,从而使较少的阻燃剂含量,也能显著提高纤维素薄膜材料的极限氧指数和阻燃性能。(The invention relates to the technical field of flame retardant materials, and discloses a nitrogen-phosphorus synergistic flame retardant modified cellulose film material, performing Mannich reaction on p-phenylenediamine, formaldehyde and phosphorous acid, then generating N, N-dimethylene phenyl ammonium phosphate with urea as a nitrogen-phosphorus synergistic flame retardant, then under the catalytic action of dicyandiamide, ammonium ions of the N, N-dimethylene phenyl phosphate ester cellulose are subjected to substitution reaction with hydroxyl of cellulose to obtain N, N-dimethylene phenyl phosphate ester cellulose grafted and modified by the nitrogen-phosphorus synergistic flame retardant, the N, N-dimethylene phenyl phosphate ester cellulose is further plasticized and filmed to obtain the nitrogen-phosphorus synergistic flame retardant modified cellulose film material, through chemical covalent grafting, the nitrogen-phosphorus synergistic flame retardant is introduced into a cellulose matrix, so that the flame retardant is highly dispersed in the cellulose membrane matrix, thereby leading the content of the flame retardant to be less and also being capable of obviously improving the limit oxygen index and the flame retardant property of the cellulose film material.)

1. A nitrogen-phosphorus synergistic flame retardant modified cellulose film material is characterized in that: the preparation method of the nitrogen-phosphorus synergistic flame retardant modified cellulose film material comprises the following steps:

(1) adding p-phenylenediamine, phosphorous acid and formaldehyde solution into a mixed solvent of distilled water and ethanol, placing the mixture into an oil bath reaction kettle, heating the mixture to 80-100 ℃, stirring the mixture for reaction for 6-12h, adding urea, stirring the mixture for reaction for 6-12h, carrying out reduced pressure distillation, washing a product, and recrystallizing and purifying the product to prepare N, N-dimethylene phenyl ammonium phosphate;

(2) adding cellulose, N-dimethylene phenyl ammonium phosphate and dicyandiamide into a mixed solvent of distilled water and ethanol, stirring and dissolving, pouring into a reaction kettle, heating to 60-80 ℃, reacting for 24-48h, carrying out reduced pressure distillation, washing and drying to prepare N, N-dimethylene phenyl phosphate cellulose;

(3) dissolving N, N-dimethylene phenyl phosphate cellulose, a plasticizer and a gelling agent in a distilled water solvent, uniformly stirring, pouring into a film forming mold, defoaming in vacuum, and curing to form a film to prepare the nitrogen-phosphorus synergistic flame retardant modified cellulose film material.

2. The nitrogen-phosphorus synergistic flame retardant modified cellulose film material according to claim 1, characterized in that: the mass ratio of the p-phenylenediamine, the phosphorous acid, the formaldehyde and the urea in the step (1) is 100:320-360:120-140: 150-250.

3. The nitrogen-phosphorus synergistic flame retardant modified cellulose according to claim 1A film material characterized by: the molecular formula of the N, N-dimethylene phenyl ammonium phosphate in the step (1) is C₁₀H₃₂O₁₂N₆P₄Chemical structural formula is

4. The nitrogen-phosphorus synergistic flame retardant modified cellulose film material according to claim 1, characterized in that: the cellulose in the step (2) is any one of hydroxymethyl cellulose, hydroxyethyl cellulose or hydroxypropyl cellulose, and the mass ratio of the cellulose to the N, N-dimethylene phenyl ammonium phosphate and the dicyandiamide is 100:8-20: 1-3.

5. The nitrogen-phosphorus synergistic flame retardant modified cellulose film material according to claim 1, characterized in that: the plasticizer in the step (3) is glycerol, the gelling agent is carrageenan, and the mass ratio of the N, N-dimethylene phenyl phosphate-based cellulose to the glycerol to the carrageenan is 100:50-80: 30-40.

Technical Field

The invention relates to the technical field of flame retardant materials, in particular to a nitrogen-phosphorus synergistic flame retardant modified cellulose film material and a preparation method thereof.

Background

The flame retardant is a functional assistant for improving the flame retardant property of a polymer material, and the traditional flame retardant mainly comprises a halogen flame retardant, a nitrogen-phosphorus flame retardant, a nitrogen-series flame retardant, a silicon-series flame retardant and the like, wherein the nitrogen-phosphorus flame retardant has excellent flame retardant property, is thermally decomposed at high temperature to produce a phosphoric acid derivative, has the functions of promoting carbonization and inhibiting combustion free radical chain reaction, can be simultaneously thermally decomposed to generate nitrogen, ammonia and other non-combustible gases, can dilute the concentration of oxygen and further inhibit the combustion process, and the traditional combustion free radical chain reaction comprises ammonium polyphosphate, melamine phosphate, cyclophosphamide polymer and the like.

Cellulose is a polysaccharide compound which is widely distributed and contains most polysaccharide compounds in nature, such as polymerized cellulose, lignocellulose, cellulose ether and the like, is a natural high polymer material with excellent biocompatibility and biodegradability, can be prepared into materials such as cellulose films, cellulose aerogels, cellulose hydrogels and the like, and has important application in the fields of medicine, medical drug carriers, packaging materials and the like, but the traditional cellulose materials are easy to burn and poor in flame retardant property, limit the practical application of the cellulose materials, and therefore, the improvement of the performances such as the flame retardant property of the cellulose materials becomes a research hotspot.

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a nitrogen-phosphorus synergistic flame retardant modified cellulose film material and a preparation method thereof, and solves the problem of poor flame retardant property of a cellulose film.

(II) technical scheme

In order to achieve the purpose, the invention provides the following technical scheme: the preparation method of the nitrogen-phosphorus synergistic flame retardant modified cellulose film material comprises the following steps:

(1) adding a mixed solvent of distilled water and ethanol, adding p-phenylenediamine, phosphorous acid and formaldehyde solution into a reaction bottle, placing the mixture into an oil bath reaction pot, heating the mixture to 80-100 ℃, stirring the mixture for reaction for 6-12h, adding urea, stirring the mixture for reaction for 6-12h, distilling the mixture under reduced pressure to remove the solvent, washing the product with diethyl ether, adding distilled water for recrystallization and purification, and preparing the N, N-dimethylene phenyl ammonium phosphate.

(2) Adding cellulose, N-dimethylene phenyl ammonium phosphate and dicyandiamide into a mixed solvent of distilled water and ethanol, stirring and dissolving, pouring into a reaction kettle, heating to 60-80 ℃, reacting for 24-48h, carrying out reduced pressure distillation, washing and drying to prepare the N, N-dimethylene phenyl phosphate cellulose.

(3) Dissolving N, N-dimethylene phenyl phosphate cellulose, a plasticizer and a gelling agent in a distilled water solvent, uniformly stirring, pouring into a film forming mold, defoaming in vacuum, and curing to form a film to prepare the nitrogen-phosphorus synergistic flame retardant modified cellulose film material.

Preferably, the mass ratio of the p-phenylenediamine, the phosphorous acid, the formaldehyde and the urea in the step (1) is 100:320-360:120-140: 150-250.

Preferably, the ammonium N, N-dimethylene phenyl phosphate in the step (1) has the formula C₁₀H₃₂O₁₂N₆P₄Chemical structural formula is

Preferably, the cellulose in the step (2) is any one of hydroxymethyl cellulose, hydroxyethyl cellulose or hydroxypropyl cellulose, and the mass ratio of the cellulose to the N, N-dimethylene phenyl ammonium phosphate salt and the dicyandiamide is 100:8-20: 1-3.

Preferably, the plasticizer in the step (3) is glycerol, the gelling agent is carrageenan, and the mass ratio of the N, N-dimethylene phenyl phosphate-based cellulose to the glycerol and the carrageenan is 100:50-80: 30-40.

Drawings

FIG. 1 is a chemical structural formula of an ammonium N, N-dimethylene phenyl phosphate salt;

FIG. 2 is a reaction equation for p-phenylenediamine, phosphorous acid and formaldehyde.

(III) advantageous technical effects

Compared with the prior art, the invention has the following beneficial technical effects:

according to the nitrogen-phosphorus synergistic flame retardant modified cellulose film material, p-phenylenediamine, formaldehyde and phosphorous acid are subjected to Mannich reaction, a phosphate group is subjected to reaction with urea to generate N, N-dimethylene phenyl ammonium phosphate salt serving as a nitrogen-phosphorus synergistic flame retardant, ammonium ions of the phosphate group and hydroxyl of cellulose are subjected to substitution reaction under the catalytic action of dicyandiamide to obtain nitrogen-phosphorus synergistic flame retardant graft modified N, N-dimethylene phenyl phosphate cellulose, the nitrogen-phosphorus synergistic flame retardant graft modified cellulose film material is further plasticized and formed into a film, the nitrogen-phosphorus synergistic flame retardant modified cellulose film material is obtained, and the nitrogen-phosphorus synergistic flame retardant is introduced into a cellulose matrix through chemical covalent grafting to highly disperse the flame retardant in the cellulose matrix, so that the content of the flame retardant is less, and the limiting oxygen index and the flame retardant performance of the cellulose film material can be remarkably improved.

Detailed Description

To achieve the above object, the present invention provides the following embodiments and examples: a nitrogen-phosphorus synergistic flame retardant modified cellulose film material is prepared by the following steps:

(1) adding a mixed solvent of distilled water and ethanol into a reaction bottle, adding p-phenylenediamine, phosphorous acid and a formaldehyde solution, placing the mixture into an oil bath reaction pot, heating the mixture to 80-100 ℃, stirring the mixture for reaction for 6-12h, adding urea, wherein the mass ratio of the p-phenylenediamine, the phosphorous acid, the formaldehyde and the urea is 100:320-₁₀H₃₂O₁₂N₆P₄The ammonium salt of N, N-dimethylenephenylphosphoric acid of (1).

(2) Adding cellulose, N-dimethylene phenyl ammonium phosphate and dicyandiamide into a mixed solvent of distilled water and ethanol in a mass ratio of 100:8-20:1-3, wherein the cellulose is any one of hydroxymethyl cellulose, hydroxyethyl cellulose or hydroxypropyl cellulose, stirring and dissolving, pouring into a reaction kettle, heating to 60-80 ℃, reacting for 24-48h, carrying out reduced pressure distillation, washing and drying to obtain the N, N-dimethylene phenyl phosphate-based cellulose.

(3) Dissolving N, N-dimethylene phenyl phosphate-based cellulose, glycerol serving as a plasticizer and carrageenan serving as a gelling agent in a mass ratio of 100:50-80:30-40 in a distilled water solvent, uniformly stirring, pouring into a film forming mold, defoaming in vacuum, and curing to form a film to prepare the nitrogen-phosphorus synergistic flame retardant modified cellulose film material.

Example 1

(1) Adding a mixed solvent of distilled water and ethanol into a reaction bottle, adding p-phenylenediamine, phosphorous acid and a formaldehyde solution, placing the mixture into an oil bath reaction pot, heating the mixture to 80 ℃, stirring the mixture for reaction for 6 hours, adding urea, wherein the mass ratio of the p-phenylenediamine to the phosphorous acid to the formaldehyde solution to the urea is 100:320:120:150, stirring the mixture for reaction for 6 hours, distilling the mixture under reduced pressure to remove the solvent, washing the product with diethyl ether, adding distilled water to the product for recrystallization and purification, and preparing the compound with the molecular formula of C₁₀H₃₂O₁₂N₆P₄The ammonium salt of N, N-dimethylenephenylphosphoric acid of (1).

(2) Adding hydroxymethyl cellulose, N-dimethylene phenyl ammonium phosphate and dicyandiamide into a mixed solvent of distilled water and ethanol in a mass ratio of 100:8:1, stirring to dissolve, pouring into a reaction kettle, heating to 60 ℃, reacting for 24 hours, distilling under reduced pressure, washing and drying to obtain the N, N-dimethylene phenyl phosphate cellulose.

(3) Dissolving N, N-dimethylene phenyl phosphate-based cellulose, glycerol serving as a plasticizer and carrageenan serving as a gelling agent in a mass ratio of 100:50:30 in a distilled water solvent, uniformly stirring, pouring into a film forming mold, defoaming in vacuum, and curing to form a film to prepare the nitrogen-phosphorus synergistic flame retardant modified cellulose film material 1.

Example 2

(1) Adding a mixed solvent of distilled water and ethanol into a reaction bottle, adding p-phenylenediamine, phosphorous acid and a formaldehyde solution, placing the mixture into an oil bath reaction pot, heating the mixture to 80 ℃, stirring the mixture for reaction for 12 hours, adding urea, wherein the mass ratio of the p-phenylenediamine to the phosphorous acid to the formaldehyde solution to the urea is 100:330:125:180, stirring the mixture for reaction for 12 hours, distilling the mixture under reduced pressure to remove the solvent, washing the product with diethyl ether, adding distilled water for recrystallization and purification, and preparing the compound with the molecular formula of C₁₀H₃₂O₁₂N₆P₄The ammonium salt of N, N-dimethylenephenylphosphoric acid of (1).

(2) Adding hydroxyethyl cellulose, N-dimethylene phenyl ammonium phosphate and dicyandiamide into a mixed solvent of distilled water and ethanol in a mass ratio of 100:12:1.5, stirring and dissolving, pouring into a reaction kettle, heating to 70 ℃, reacting for 48 hours, distilling under reduced pressure, washing and drying to obtain the N, N-dimethylene phenyl phosphate cellulose.

(3) Dissolving N, N-dimethylene phenyl phosphate-based cellulose, glycerol serving as a plasticizer and carrageenan serving as a gelling agent in a mass ratio of 100:60:33 in a distilled water solvent, uniformly stirring, pouring into a film forming mold, defoaming in vacuum, and curing to form a film to prepare the nitrogen-phosphorus synergistic flame retardant modified cellulose film material 2.

Example 3

(1) Adding a mixed solvent of distilled water and ethanol into a reaction bottle, adding p-phenylenediamine, phosphorous acid and a formaldehyde solution, placing the mixture into an oil bath reaction pot, heating the mixture to 100 ℃, stirring the mixture for reaction for 6 hours, adding urea, wherein the mass ratio of the p-phenylenediamine to the phosphorous acid to the formaldehyde solution to the urea is 100:350:135:220, stirring the mixture for reaction for 10 hours, distilling the mixture under reduced pressure to remove the solvent, washing the product with diethyl ether, adding distilled water to the product for recrystallization and purification, and preparing the compound with the molecular formula of C₁₀H₃₂O₁₂N₆P₄The ammonium salt of N, N-dimethylenephenylphosphoric acid of (1).

(2) Adding hydroxypropyl cellulose, N-dimethylene phenyl ammonium phosphate and dicyandiamide into a mixed solvent of distilled water and ethanol in a mass ratio of 100:16:2.5, stirring and dissolving, pouring into a reaction kettle, heating to 70 ℃, reacting for 36 hours, distilling under reduced pressure, washing and drying to obtain the N, N-dimethylene phenyl phosphate cellulose.

(3) Dissolving N, N-dimethylene phenyl phosphate-based cellulose, glycerol serving as a plasticizer and carrageenan serving as a gelling agent in a mass ratio of 100:70:36 in a distilled water solvent, uniformly stirring, pouring into a film forming mold, defoaming in vacuum, and curing to form a film to prepare the nitrogen-phosphorus synergistic flame retardant modified cellulose film material 3.

Example 4

(1) Adding a mixed solvent of distilled water and ethanol, adding p-phenylenediamine, phosphorous acid and a formaldehyde solution into a reaction bottle, placing the reaction bottle in an oil bath reaction kettle, heating the reaction bottle to 100 ℃, stirring the reaction bottle for 12 hours, and adding urea, wherein the mass ratio of the p-phenylenediamine, the phosphorous acid, the formaldehyde and the urea is100:360:140:250, stirring for 12h, distilling under reduced pressure to remove the solvent, washing the product with diethyl ether, adding distilled water for recrystallization and purification to obtain the compound with the molecular formula C₁₀H₃₂O₁₂N₆P₄The ammonium salt of N, N-dimethylenephenylphosphoric acid of (1).

(2) Adding hydroxyethyl cellulose, N-dimethylene phenyl ammonium phosphate and dicyandiamide into a mixed solvent of distilled water and ethanol in a mass ratio of 100:20:3, stirring to dissolve, pouring into a reaction kettle, heating to 80 ℃, reacting for 48 hours, distilling under reduced pressure, washing and drying to obtain the N, N-dimethylene phenyl phosphate cellulose.

(3) Dissolving N, N-dimethylene phenyl phosphate-based cellulose, glycerol serving as a plasticizer and carrageenan serving as a gelling agent in a mass ratio of 100:80:40 in a distilled water solvent, uniformly stirring, pouring into a film forming mold, defoaming in vacuum, and curing to form a film to prepare the nitrogen-phosphorus synergistic flame retardant modified cellulose film material 4.

Comparative example 1

(1) Adding a mixed solvent of distilled water and ethanol into a reaction bottle, adding p-phenylenediamine, phosphorous acid and a formaldehyde solution, placing the mixture into an oil bath reaction pot, heating the mixture to 100 ℃, stirring the mixture for reaction for 6 hours, adding urea, wherein the mass ratio of the p-phenylenediamine to the phosphorous acid to the formaldehyde solution to the urea is 100:300:110:130, stirring the mixture for reaction for 12 hours, distilling the mixture under reduced pressure to remove the solvent, washing the product with diethyl ether, adding distilled water to the product for recrystallization and purification, and preparing the compound with the molecular formula of C₁₀H₃₂O₁₂N₆P₄The ammonium salt of N, N-dimethylenephenylphosphoric acid of (1).

(2) Adding hydroxymethyl cellulose, N-dimethylene phenyl ammonium phosphate and dicyandiamide into a mixed solvent of distilled water and ethanol in a mass ratio of 100:5:0.5, stirring and dissolving, pouring into a reaction kettle, heating to 80 ℃, reacting for 24 hours, distilling under reduced pressure, washing and drying to obtain the N, N-dimethylene phenyl phosphate cellulose.

(3) Dissolving N, N-dimethylene phenyl phosphate-based cellulose, glycerol serving as a plasticizer and carrageenan serving as a gelling agent in a mass ratio of 100:40:26 in a distilled water solvent, uniformly stirring, pouring into a film forming mold, defoaming in vacuum, and curing to form a film, thereby preparing the nitrogen-phosphorus synergistic flame retardant modified cellulose film material, wherein the nitrogen-phosphorus synergistic flame retardant modified cellulose film material is comparative 1.

The limit oxygen index of the nitrogen-phosphorus synergistic flame retardant modified cellulose film material is tested by using a limit oxygen index tester, and the test standard is GB/T5454-1997.