CN106496551A - A kind of organophosphorus copolymer flame-retardant polyamide and preparation method thereof - Google Patents

Abstract

The invention discloses an organic phosphorus copolymerized flame-retardant polyamide and a preparation method thereof. The preparation method specifically comprises the following steps: (A) reacting an organic phosphorus flame-retardant monomer with a diamine monomer to form salt; (B) and (2) adding diacid, diamine or diamine salt or solution thereof, the salt or solution thereof obtained in the step (A), an antioxidant, a catalyst and deionized water into a reaction kettle, and preparing the required organic phosphorus copolymerization flame-retardant polyamide material by regulating and controlling the reaction temperature and pressure under the nitrogen atmosphere. The organic phosphorus polyamide material prepared by the invention has the advantages of small addition amount of the reaction flame retardant, no need of adding a synergistic flame retardant, controllable viscosity in the preparation process, excellent mechanical property of the obtained product, excellent flame retardant property, and suitability for various fields such as textiles, insulating materials, tire cords, films and the like.

Description

A kind of organophosphorus copolymer flame-retardant polyamide and preparation method thereof

technical field

The invention belongs to the technical field of flame-retardant polymer synthesis, and relates to a preparation method of copolymerized flame-retardant polyamide, in particular to a polymer material containing a phosphorus-containing reactive flame retardant copolymerized and embedded in polyamide molecular chains and a preparation method thereof.

Background technique

Polyamide is widely used in construction, chemical industry, transportation and military fields because of its excellent properties, such as high strength, heat resistance, wear resistance, solvent resistance, etc. However, polyamide itself is not flame retardant and may cause or aggravate fires. Therefore, how to modify and prepare polyamides with good flame retardant properties has been researched by industry personnel.

There are usually two ways to modify the flame retardant polyamide material: one is to add a reactive flame retardant to introduce a functional group with flame retardant activity during the nylon copolymerization process; the other is to add Type flame retardants and related synergistic flame retardants, blending processing. Among them, the physical blending method of the latter will be affected by factors such as dispersibility, compatibility, and interfaciality, while the former does not have these problems due to the occurrence of chemical reactions. In addition, in order to achieve a certain flame retardancy, the amount of additive flame retardant used will be relatively large, which will cause great damage to the mechanical and electrical properties and limit its application. The reactive flame retardant can solve these problems very well. Its molecular structure is copolymerized into the main chain of polyamide molecules, and there are no problems such as volatilization, migration, and exudation, and can provide reliable flame retardant performance within the service life of the material.

At present, the commonly used flame retardants mainly include halogen flame retardants, phosphorus flame retardants, nitrogen flame retardants, inorganic filler flame retardants and so on. The first few of them can be used as reactive flame retardants. Halogen-containing flame retardants have been widely used in high-polymer flame-retardant materials due to their high-efficiency flame-retardant properties. However, due to the generation of toxic gases and smoke during combustion, which are harmful to the environment and human body, their use is gradually restricted. . Phosphorus-based flame retardants, especially organophosphorus-based flame retardants, are promising to replace halogen-containing flame retardants. Phosphorus-based flame retardants can act in both the condensed phase and the gas phase. The flame retardant mechanism is that the flame retardants will produce phosphoric acid and polyphosphoric acid and other products during the combustion process, which will promote the dehydration and carbonization of the polymer and form a glass-like protective layer. , to prevent the transfer of heat and matter between the condensed phase and the gas phase. The combustion process of phosphorus-containing flame retardants will not produce toxic and harmful gases, and the amount of smoke will be less, which has a good flame-retardant effect. In particular, reactive phosphorus-based flame retardants can be polymerized to enter the molecular backbone of polymer materials that need to be flame-retardant, and they do not migrate or bleed out and are effective for a long time.

The patent with publication number CN104231262A discloses a preparation method of organophosphorus copolymerized flame-retardant polyamide, the steps are: (1) react flame-retardant monomer and diamine monomer in advance to prepare prepolymer; The polymerization monomer, the catalyst and the prepolymer are added into the reactor in a certain order. The flame retardants described in this patent are Or a derivative based on the substrate; wherein said R ₁ and R ₂ are both alkylene groups of 1-10 carbon atoms; or any one of R ₁ and R ₂ is H; X ₁ and X ₂ are H or 1-4 halogens that can replace H on the benzene ring. The flame retardant grade of the copolymerized product obtained in the present invention can reach the UL94V-0 grade, and the limiting oxygen index is greatly improved, the lowest value can reach 32, and the highest value can reach 45.

The patent with publication number CN104262619A relates to a phosphorus-containing flame-retardant polyamide and its preparation method and application. The preparation method comprises: (1) performing precondensation reaction of hypophosphite used for flame retardancy and diamine to generate oligomer; (2) performing precondensation reaction of oligomer and dicarboxylic acid salt under nitrogen atmosphere, Obtaining a prepolymer; (3) after two precondensation reactions, raising the temperature to reduce the air pressure to normal pressure; (4) raising the temperature, pumping to a vacuum, and discharging to obtain a flame-retardant polyamide material. The flame retardants described in this patent are

Wherein R ₁ and R ₂ are linear, branched or cyclic C ₁ -C ₁₅ alkylene, C ₆ -C ₁₅ arylene or aralkylene; M is a metal element, when a is 1, M is lithium, sodium or potassium; when a is 2, M is calcium or magnesium. In this invention, when the phosphorus content reaches above 0.48%, the flame-retardant polyamide can pass the UL-94V-0 level, and the LOI value also increases significantly.

The patent with the publication number JPH09328543 relates to a polyamide copolymer containing phosphorus in the main chain and a preparation method thereof. The preparation method is as follows: (1) pre-reaction of phosphorus-containing dicarboxylate and diamine to form a salt; (2) polycondensation of the salt with other comonomers (diacid and diamine, or caprolactam) to prepare polyamide copolymer. In this patent, the dicarboxylate is

Wherein R ¹ is a straight chain or branched chain alkyl group with 1-8 carbon atoms; R ² is H or methyl. When the phosphorus content in the prepared polyamide copolymer is 6.48-6.58ppm, its limiting oxygen index can reach 28.9-29.9%, and it has good flame retardancy. However, the relative viscosity of the prepared polyamide material is only 0.78-0.82, and there is still a lot of room for improvement in the mechanical properties and other properties of the material samples.

As mentioned above, although many phosphorus-containing polyamides with good flame-retardant properties have been proposed in the prior art, there is still a strong demand for flame-retardant polyamides with excellent mechanical properties and flame-retardant properties.

Contents of the invention

The purpose of the present invention is to prepare a novel organophosphorus-based copolymerized flame-retardant polyamide material in view of the fact that the current flame-retardant polyamide market is mainly based on blending. Its characteristic is to use the characteristics of two carboxylic acid groups in the flame retardant monomer to form a salt with a dibasic amine, and then polycondense with a dibasic carboxylic acid amine salt to prepare a new type of organophosphorus copolymerized flame retardant polyamide. In this process, the amount of flame retardant added is small and no synergistic flame retardant is required, and the obtained polyamide material has excellent mechanical and electrical properties.

Technical scheme of the present invention:

A kind of flame-retardant polyamide, its general formula is as shown in following formula (1):

Wherein, R is selected from H, C ₁ -C ₅ alkyl, C ₆ -C ₁₀ aryl, C ₃ -C ₁₀ heteroaryl; R is preferably H, C ₁ -C ₃ alkyl, C ₆ -C ₈ Aryl, or C ₃ -C ₆ heteroaryl;

R ₁ and R ₂ are each independently selected from linear, branched or cyclic C ₁ -C ₁₀ alkylene, C ₆ -C ₁₅ arylene or aralkylene, C ₃ -C ₁₀ ester groups; R _1. Each R ₂ is independently preferably a linear, branched or cyclic C ₁ -C ₅ alkylene group, C ₆ -C ₁₀ arylene group or aralkylene group, or a C ₃ -C ₈ ester group;

R ₃ , R ₄ , R ₅ are each independently selected from C ₃ -C ₁₂ linear, branched or cyclic alkylene, C ₆ -C ₁₀ arylene, C ₃ -C ₁₀ heteroaryl; R ₃ , R ₄ and R ₅ are each independently preferably C _3- C ₈ linear, branched or cyclic alkylene, C ₆ -C ₈ arylene, C ₃ -C ₈ heteroaryl;

x represents 1-50, y represents 1-50, n represents 1-100; x is preferably 2-30, y is preferably 2-30, n is preferably 2-80, more preferably 5-50.

The preparation method of above-mentioned flame-retardant polyamide, comprises the following steps:

(A) reacting the organophosphorus flame retardant monomer of formula (2) or its derivatives with the diamine monomer of formula (3);

Wherein, R is selected from H, C ₁ -C ₅ alkyl, C ₆ -C ₁₀ aryl, C ₃ -C ₁₀ heteroaryl; R is preferably H, C ₁ -C ₃ alkyl, C ₆ -C ₈ Aryl, C ₃ -C ₆ heteroaryl;

R ₁ and R ₂ are each independently selected from linear, branched or cyclic C ₁ -C ₁₀ alkylene groups, C ₆ -C ₁₅ arylene groups or aralkylene groups, and C ₃ -C ₁₀ ester groups; R ₁ and R ₂ are each independently preferably linear, branched or cyclic C ₁ -C ₅ alkylene, C ₆ -C ₁₀ arylene or aralkylene, C ₃ -C ₈ ester group;

R ₃ is selected from C ₃ -C ₁₂ linear, branched or cyclic alkylene, C ₆ -C ₁₀ arylene, C ₃ -C ₁₀ heteroaryl; R ₃ is preferably C ₃ -C ₈ linear, branched Or cyclic alkylene, C ₆ -C ₈ arylene, C ₃ -C ₈ heteroaryl;

Compounds of the following formula (4) are obtained:

(B) allow the compound of formula (4) to react with the diacid of formula (5) and the diamine of formula (6), or react with the dibasic amide salt of formula (7) or its solution,

Wherein, R ₄ and R ₅ are selected from C ₃ -C ₁₂ linear, branched or cyclic alkylene, C ₆ -C ₁₀ arylene, C ₃ -C ₁₀ heteroaryl; R ₄ and R ₅ are preferably C ₃ -C ₈ linear, branched or cyclic alkylene, C ₆ -C ₈ arylene, C ₃ -C ₈ heteroaryl;

A polyamide of formula (1) is obtained:

Wherein, R, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , x, y, and n are as defined above.

Preferably, the flame retardant monomer of formula (2) reacts with the diamine monomer of formula (3) in a molar ratio of 1:0.1-20, preferably 1:0.5-10, more preferably 1:1-2.

In step (A), the reaction is usually carried out in the presence of a solvent such as water or an organic solvent such as an alcoholic solvent. Preferably, a slight excess of diamine monomers (such as 0.1-10%, preferably 0.5-5% molar excess ), so that the pH of the prepared salt solution is 7-9. The reaction temperature rose from room temperature to 40-70°C within 5-20 minutes.

Preferably, the diamine monomers described in step (A) are hexamethylenediamine, decanediamine, nonanediamine, undecanediamine, dodecanediamine, aliphatic C ₆ -C ₂₀ iminodiamine One or more of amines, aromatic diamines, and alicyclic diamines.

In step (B), the mol ratio of the diacid of formula (5) and the diamine of formula (6) is not particularly limited, for example the mol ratio of the diacid of formula (5) and the diamine of formula (6) can be 1:1.01-10, preferably 1:1.1-2, more preferably about 1:1.5.

In step (B), preferably, diacid and diamine or dibasic amide salt or its solution, step (A) reaction product (salt or salt solution), antioxidant, catalyst, deionized water are added to react In a nitrogen atmosphere, adjust the reaction temperature and pressure to obtain the desired organophosphorus copolymerized flame-retardant polyamide.

In step (B), further, the polymerized monomer diacid is, for example, adipic acid, sebacic acid, azelaic acid, undecanedioic acid, dodecanedioic acid, terephthalic acid, isophthalic acid One or more of dicarboxylic acid, phthalic acid or their derivatives and other aliphatic and aromatic dicarboxylic acids; diamines such as hexamethylenediamine, nonanediamine, decanediamine, undecanediamine One or more of amine, dodecanediamine, and aliphatic C ₆ -C ₂₀ iminodiamine, aromatic diamine or alicyclic diamine; and the dibasic amide salt is adipamide Amine salt, adipyl pentamethylenediamine salt, azelayl hexamethylene diamine salt, sebacoyl hexamethylene diamine salt, sebacoyl octyl diamine salt, suberoyl hexamethylene diamine salt, suberoyl octyl diamine salt one or more of.

Further, the antioxidants are compounds such as p-phenylenediamine and dihydroquinoline and derivatives thereof, 2,6-di-tert-butyl-4-methylphenol, bis(3,5-di-tert-butyl One or more of -4-hydroxyphenyl)sulfide, tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]pentaerythritol ester, etc.

Further, the catalyst is one or more of sodium hypophosphite, toluenesulfonic acid, neoferrocene chiral polyamide ligand, and the like.

Further preferably, in step (B), specifically include the following steps:

a. Add the polymerized monomer diacid and diamine or dibasic amide salt or its solution, the reaction product obtained in step (A), catalyst, antioxidant, and deionized water to the reactor, vacuumize, and fill with nitrogen several times, so that In the initial stage of the reaction, the pressure in the kettle is 0.1-0.5MPa;

b. Heat the reaction kettle, raise the temperature to 200-250°C, and when the pressure is 1.6-2.1MPa, maintain the reaction conditions for 30-180min;

c. Slowly release the pressure to normal pressure at 230-280°C, then vacuumize to -0.01 to -0.1MPa, and then copolymerize for 10-180min.

d. Finally, fill with nitrogen, discharge materials, cool, pelletize, extract, and dry to obtain the final product.

Further, in step a, the addition amount of the polymerized monomer diacid and diamine or dibasic amide salt or its solution is 8-100 times, preferably 12-30 times, the mass of the flame retardant; the catalyst , antioxidant are respectively 0.01%～1.0% of the mass of the polymerized monomer, preferably 0.05-0.5%, more preferably 0.08-0.2%, more preferably such as about 1/1000; the amount of water added in the system (including adding separately The water, the water brought in with the product of step (A) and the water brought in with the dibasic amide salt) are 10-60% of the total mass of the reactants, preferably 30-50%.

In the present invention, the flame retardant and the diamine monomer are preferably salted according to, for example, 1: (1-2), and then the obtained salt is added to the polymerized monomer to participate in the polymerization reaction under the action of a catalyst. The flame retardancy properties of the obtained polyamide materials all meet the requirements of flame retardancy grade UL-94V-0.

by Hexamethylenediamine and PA66 salt are taken as examples. The mechanism of the reaction is: the flame retardant monomer first reacts with hexamethylenediamine to form a salt, and then the salt is copolymerized with nylon 66 salt to form a flame retardant polyamide. The reaction process can be written as:

The beneficial effects of the present invention are:

As long as the flame-retardant polyamide containing phosphorus-containing flame-retardant monomer accounts for about 6% of the total mass of the reactants, it can basically reach the UL-94V-0 level, and the limiting oxygen index ranges from 27% to 32%, low smoke and low toxicity, Efficient and stable, with controllable viscosity, solves the problem that many phosphorus-containing monomers disclosed in the prior art cannot achieve a higher degree of polymerization when the phosphorus content is increased.

detailed description

The present invention will be described in further detail below in conjunction with specific examples.

The organophosphorus flame retardant polyamide molecular structure of the present invention is as shown in formula 1 below:

Wherein, R is selected from H, C ₁ -C ₅ alkyl, C ₆ -C ₁₀ aryl, C ₃ -C ₁₀ heteroaryl; R is preferably H, C ₁ -C ₃ alkyl, C ₆ -C ₈ Aryl, C ₃ -C ₆ heteroaryl;

R ₁ and R ₂ are each independently selected from linear, branched or cyclic C ₁ -C ₁₀ alkylene, C ₆ -C ₁₅ arylene or aralkylene, C ₃ -C ₁₀ ester groups; R _1. Each R ₂ is independently preferably a linear, branched or cyclic C ₁ -C ₅ alkylene group, C ₆ -C ₁₀ arylene group or aralkylene group, or a C ₃ -C ₈ ester group;

R ₃ , R ₄ , R ₅ are each independently selected from C ₃ -C ₁₂ linear, branched or cyclic alkylene, C ₆ -C ₁₀ arylene, C ₃ -C ₁₀ heteroaryl; R ₃ , R ₄ and R ₅ are each independently preferably C _3- C ₈ linear, branched or cyclic alkylene, C ₆ -C ₈ arylene, C ₃ -C ₈ heteroaryl;

x represents 1-50, y represents 1-50, n represents 1-100; x is preferably 2-30, y is preferably 2-30, n is preferably 2-80, more preferably 5-50.

The preparation method of the organophosphorus copolymerized flame-retardant polyamide of the present invention specifically comprises the following steps:

(A) reacting an organophosphorus flame retardant monomer with a diamine, preferably making the amino group excessive, to generate a salt solution;

(B) reacting the reaction product of step (A) with diacid and diamine or dibasic amide salt or its solution to prepare organophosphorus copolymerized flame-retardant polyamide.

In step (A), preferably, the diamine monomer is slightly excessive, so that the pH of the salt solution is 7-9. The reaction temperature rose from room temperature to 40-70°C within 5-20 minutes.

Preferably, the diamine monomers described in step (A) are hexamethylenediamine, decanediamine, nonanediamine, undecanediamine, dodecanediamine, aliphatic C ₆ -C ₂₀ iminodiamine One or more of amines, aromatic diamines, and alicyclic diamines.

In step (B), preferably, the polymerized monomer, the reaction product of step (A), antioxidant, catalyst, and deionized water are added to the reactor, and under a nitrogen atmosphere, the reaction temperature and pressure are regulated to obtain the desired Organophosphorus copolymer flame retardant polyamide material.

In step (B), further, the dibasic acid of the polymerized monomer is, for example, adipic acid, sebacic acid, azelaic acid, undecanedioic acid, dodecanedioic acid, terephthalic acid, isophthalic acid, One or more of phthalic acid, phthalic acid or their derivatives and other aliphatic and aromatic dicarboxylic acids; diamine compounds such as hexamethylenediamine, nonanediamine, decanediamine, One or more of undecanediamine, dodecanediamine, and aliphatic C ₆ -C ₂₀ iminodiamine, aromatic diamine or alicyclic diamine; the dibasic amide salts Compounds such as polyhexamethylene adipamide, polypentamethylene adipamide, polyhexamethylene azelayl, polyhexamethylene sebacamide, polyoctyl sebacamide, hexamethylene suberamide , polyhexamethylene dodecamide, polyoctylene suberoyl diamide, etc., or one or more of them.

Further, the antioxidants are compounds such as p-phenylenediamine and dihydroquinoline and derivatives thereof, 2,6-di-tert-butyl-4-methylphenol, bis(3,5-di-tert-butyl One or more of -4-hydroxyphenyl)sulfide, tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]pentaerythritol ester, etc.

Further, the catalyst is one or more of sodium hypophosphite, toluenesulfonic acid, neoferrocene chiral polyamide ligand, and the like.

Further preferably, in step (B), specifically include the following steps:

a. Add the polymerized monomer diacid and diamine or dibasic amide salt or its solution, the reaction product obtained in step (A), catalyst, antioxidant, and deionized water to the reactor, vacuumize, and fill with nitrogen several times, so that In the initial stage of the reaction, the pressure in the kettle is 0.1-0.5MPa;

b. Heat the reaction kettle, raise the temperature to 200-250°C, and when the pressure is 1.6-2.1MPa, maintain the reaction conditions for 30-180min;

c. Slowly release the pressure to normal pressure at 230-280°C, then vacuumize to -0.01 to -0.1MPa, and then copolymerize for 10-180min;

d. Finally, fill with nitrogen, discharge materials, cool, pelletize, extract, and dry to obtain the final product.

Further, in step a, the addition amount of the polymerized monomer is 8-100 times the mass of the flame retardant, preferably 10-40 times, more preferably 12-30 times; the catalyst and the antioxidant are respectively 0.01% to 1.0% of the mass of the polymerized monomer (or dibasic amide salt), preferably 0.05-0.5%, more preferably 0.08-0.2%, more preferably for example about 1/1000; the amount of water added in the system is the reactant 10-60% of the total mass, preferably 30-50%.

Embodiments of the present invention are as follows:

The methods used in the following examples are conventional methods unless otherwise specified.

The materials, reagents, etc. described in the following examples were obtained from the market unless otherwise specified. "%" is in mass fraction unless otherwise specified.

Example 1:

Stir and react the flame retardant monomer and hexamethylenediamine in an aqueous solution at a molar ratio of 1:1.2 at 40°C for 0.5 h, adjust the pH of the solution to 7.2, and dry to form a salt. Add 50% nylon 66 salt (hexamethylene adipamide salt) solution, the salt obtained above, accounting for 6.0% of the salt mass, the catalyst sodium hypophosphite, and the antioxidant p-phenylenediamine, each accounting for 1‰, to react Reactor, evacuated, filled with nitrogen 5 times, and finally kept the pressure in the reactor at 0.2MPa. Heat the reactor, keep stirring at a high speed, and when the temperature of the reactor reaches 220°C and the pressure is 1.8 MPa, keep the temperature and pressure constant for 1.5 hours. Then the temperature was raised to 250°C, and the pressure was released to normal pressure within 1 hour. Vacuumize to -0.05MPa. After the stirring speed drops to a certain value and stabilizes, fill nitrogen to 0.2MPa, discharge the material, cool, cut into pellets, extract, and dry to obtain the final product with a relative viscosity of 2.3 and a limiting oxygen index of 27.5. %, the flame retardant level reaches UL94V-0 level. Wherein said organophosphorus flame retardant monomer is:

Example 2:

Stir and react the flame retardant monomer and hexamethylenediamine in an aqueous solution at a molar ratio of 1:1.3 at 50°C for 1 hour, adjust the pH of the solution to 7.8, and dry to form a salt.

Adipic acid and hexamethylenediamine are configured according to a molar ratio of 1:1.2, and the above-mentioned salts accounting for 7% of the mass of the above two, catalyst toluenesulfonic acid and antioxidant 2,6- Di-tert-butyl-4-methylphenol and 35% deionized water were added to the reactor, vacuumed and filled with nitrogen for 3 times, and finally the internal pressure of the reactor was kept at 0.3 MPa. Heat the reactor, keep stirring at a high speed, and when the temperature of the reactor reaches 215°C and the pressure is 1.7 MPa, keep the temperature and pressure constant for 1.6 hours. Then the temperature was raised to 240°C, and the pressure was released to normal pressure within 1.5 hours. Vacuumize to -0.06MPa. After the stirring speed drops to a certain value and stabilizes, fill nitrogen to 0.3MPa, discharge the material, cool, pelletize, extract, and dry to obtain the final product. The relative viscosity is 2.1 and the limiting oxygen index is 29. %, the flame retardant level reaches UL94V-0 level. Wherein said organophosphorus flame retardant monomer is:

Example 3:

Stir and react the flame retardant monomer and nonanediamine in an aqueous solution at a molar ratio of 1:1.5 at 60°C for 1 hour, adjust the pH of the solution to 7.6, and dry to form a salt. Undecanedioic acid and hexamethylenediamine with a molar ratio of 1:1.1 and 8% of the above-mentioned salts accounting for the total mass of the above two, the catalyst sodium hypophosphite and the antioxidant bis(3,5-bis) each accounting for 1‰ tert-butyl-4-hydroxyphenyl) sulfide and 40% deionized water were added to the reactor, vacuumed and filled with nitrogen 4 times, and finally the internal pressure of the reactor was kept at 0.2 MPa. Heat the reaction kettle and keep stirring at high speed. When the temperature of the reactor reaches 245°C and the pressure is 1.7 MPa, keep the temperature and pressure constant for 2 hours. Then the temperature was raised to 255°C, and the pressure was released to normal pressure within 2 hours. Vacuumize to -0.09MPa. After the stirring speed drops to a certain value and stabilizes, fill nitrogen to 0.3MPa, discharge the material, cool, pelletize, extract, and dry to obtain the final product. The relative viscosity is 2.0 and the limiting oxygen index is 32.2. %, the flame retardant grade reaches UL94V-0. Wherein said organophosphorus flame retardant monomer is:

Example 4:

Stir the flame retardant and hexamethylenediamine in an aqueous solution at 42°C for 50 minutes at a molar ratio of 1:1.2, adjust the pH of the solution to 7.4, and dry to form a salt. Undecanedioic acid and octyldiamine with a molar ratio of 1:1.15 and the above-mentioned salts accounting for 8% of the total mass of the above two, catalyst toluenesulfonic acid each accounting for 1‰, antioxidant tetrakis [β- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester and 40% of deionized water were added to the reactor, vacuumed and filled with nitrogen for 3 times, and finally the internal pressure of the reactor was kept at 0.35 MPa. Heat the reaction kettle and keep stirring at high speed. When the temperature of the reactor reaches 230°C and the pressure is 1.8 MPa, keep the temperature and pressure constant for 2 hours. Then the temperature was raised to 260°C, and the pressure was released to normal pressure within 1 hour. Vacuumize to -0.05MPa. After the stirring speed drops to a certain value and stabilizes, fill nitrogen to 0.3MPa, discharge the material, cool, pelletize, extract, and dry to obtain the final product. The relative viscosity is 2.05 and the limiting oxygen index is 31.5. %, the flame retardant grade reaches UL94V-0. Wherein said organophosphorus flame retardant monomer is:

Example 5

At 65°C, stir the flame retardant monomer and hexamethylenediamine in an aqueous solution at a molar ratio of 1:1.2 for 0.5h, adjust the pH of the solution to 7.3, and dry to form a salt. Add 50% nylon 66 salt (hexamethylene adipamide salt) solution, the above-mentioned salt accounting for 10.0% of the salt mass, sodium hypophosphite catalyst and antioxidant p-phenylenediamine each accounting for 1‰ to the reactor, Vacuumize, fill with nitrogen 3 times, and finally keep the pressure in the reactor at 0.25MPa. Heat the reactor, keep stirring at a high speed, and when the temperature of the reactor reaches 240°C and the pressure is 1.95 MPa, keep the temperature and pressure constant for 1.5 hours. Then the temperature was raised to 260°C, and the pressure was released to normal pressure within 1 hour. Vacuumize to -0.05MPa. After the stirring speed drops to a certain value and stabilizes, fill nitrogen to 0.4MPa, discharge the material, cool, pelletize, extract, and dry to obtain the final product. The P content is 0.82-0.86wt.%. The relative viscosity is 2.25, the limiting oxygen index is 34.0%, and the flame retardant grade reaches UL94V-0 level. Wherein said organophosphorus flame retardant monomer is:

1. Preparation of Specimen

The test samples made of polyamide materials without flame retardants are called "PA", and the test samples made of the organophosphorus flame-retardant polyamide materials obtained in the above-mentioned Examples 1-5 are called "FR" in turn. -A"-"FR-E".

The test sample preparation process of all the above samples refers to the GB/T 9532-2008 "Compression Molding of Plastic Thermoplastic Material Samples" standard.

2. Limiting Oxygen Index (LOI) Test

The limit oxygen index test refers to the standard of GB/T 2406.2-2009 "Determination of Combustion Behavior of Plastics by Oxygen Index Method", and the limit oxygen index tester is used to measure at room temperature. Spline specification: 80mm*10mm*4mm.

3. UL-94 test

The vertical burning test refers to the standard of GB/T 2408-2008 "Plastic Combustion Performance Test Methods Horizontal Method and Vertical Method", and the CFZ-5 vertical combustion tester is used to measure at room temperature. Spline specification: 125mm*13.2mm*3.2mm. Fix the spline vertically on the sample holder, the clamping part at the upper end is 6mm, the distance between the lower end of the spline and the absorbent cotton (4mm thick) is 300mm, apply flame at the bottom 10mm of the spline, and record the test data of the spline. After the spline combustion is extinguished, light it again according to the standards in Table 1, and record the test data.

Table 1 Determination grade control standard

4. Test conclusion

It can be seen from the flame retardant performance test results of the example that the existence of the organic phosphorus flame retardant structure improves the flame retardant performance of polyamide. When the flame retardant monomer content reaches more than 6%, the flame retardant polyamide can pass the V-0 test of UL-94, and the LOI value also increases accordingly. Therefore, it can be proved that the flame retardant modification of polyamide by using the reactive organophosphorus flame retardant in the present invention is feasible and efficient. The organophosphorus copolymerized flame-retardant polyamide material obtained through the scheme provided by the invention has a high limiting oxygen index and a high relative viscosity value at the same time. Due to the existence of end groups, to obtain materials with higher viscosity, the traditional solid viscosity increasing process can be used to obtain various required viscosity values.

The above descriptions are only preferred embodiments of the present invention, and do not limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims (7)

1. a kind of organophosphors system copolymerization Flameproof polyamide, its formula is such as with following formula (1) Suo Shi：

Wherein, R is selected from H, C₁-C₅Alkyl, C₆-C₁₀Aryl, C₃-C₁₀Heteroaryl；R is preferably H, C₁-C₃Alkyl, C₆-C₈Aryl, C₃- C₆Heteroaryl；

R₁、R₂It is each independently selected from straight chain, the C of branched or ring-type₁-C₁₀Alkylidene, C₆-C₁₅Arlydene or sub- aralkyl, C₃-C₁₀ Ester group；R₁、R₂Straight chain, the C of branched or ring-type are each independently preferably₁-C₅Alkylidene, C₆-C₁₀Arlydene or sub- aralkyl, C₃- C₈Ester group；

R₃、R₄、R₅It is each independently selected from C₃-C₁₂Linearly, branched or cyclic alkylidene, C₆-C₁₀Arlydene, C₃-C₁₀Heteroaryl； R₃、R₄、R₅C is each independently preferably₃-C₈Linearly, branched or cyclic alkylidene, C₆-C₈Arlydene, C₃-C₈Heteroaryl；

X represents that 1-50, y represent that 1-50, n represent 1-100；X is preferably 2-30, and y is preferably 2-30, and n is preferably 2-80, more preferably 5-50.

2. the preparation method of the Flameproof polyamide described in claim 1, comprises the following steps：

(A) diamines monomer by organophosphors system flame-retardant monomer of formula (2) or derivatives thereof with formula (3) reacts；

Wherein, R is selected from H, C₁-C₅Alkyl, C₆-C₁₀Aryl, C₃-C₁₀Heteroaryl；R is preferably H, C₁-C₃Alkyl, C₆-C₈Aryl, C₃- C₆Heteroaryl；

R₁、R₂It is each independently selected from straight chain, the C of branched or ring-type₁-C₁₀Alkylidene, C₆-C₁₅Arlydene or sub- aralkyl, C₃- C₁₀Ester group；R₁、R₂Straight chain, the C of branched or ring-type are preferably independently of one another₁-C₅Alkylidene, C₆-C₁₀Arlydene or sub- aralkyl Base, C₃-C₈Ester group；

R₃It is selected from C₃-C₁₂Linearly, branched or cyclic alkylidene, C₆-C₁₀Arlydene, C₃-C₁₀Heteroaryl；R₃Preferably C₃-C₈Linearly, Branched or cyclic alkylidene, C₆-C₈Arlydene, C₃-C₈Heteroaryl；

Obtain the compound of following formula (4)：

(B) diamine reactant of the compound of formula (4) and the diacid of formula (5) and formula (6), or the binary amidic-salt with formula (7) allowed Or its solution reaction,

Wherein, R₄And R₅It is selected from C₃-C₁₂Linearly, branched or cyclic alkylidene, C₆-C₁₀Arlydene, C₃-C₁₀Heteroaryl；R₄And R₅Excellent Elect C as₃-C₈Linearly, branched or cyclic alkylidene, C₆-C₈Arlydene, C₃-C₈Heteroaryl；

The polyamide of acquisition formula (1)：

Wherein, R, R₁、R₂、R₃、R₄、R₅, x, y, n as defined above.

3. preparation method according to claim 2, wherein, the diamines monomer of the flame-retardant monomer of formula (2) and formula (3) according to 1:0.1-20, preferably 1:0.5-10, more preferably 1:The molar ratio reaction of 1-2.

4. the preparation method according to Claims 2 or 3, wherein, in step (A), diamines monomer is slightly excessive, makes to be obtained Saline solution PH be 7-9；Reaction temperature is raised to 40-70 DEG C by room temperature in 5-20min；And/or

In step (A), the diamines monomer is hexamethylene diamine, decamethylene diamine, nonamethylene diamine, hendecane diamidogen, dodecamethylene diamine, fat Fat race C₆-C₂₀One or more in imino group diamidogen, aromatic diamine, alicyclic diamine；And/or

In step (B), change that diacid and diamidogen or binary amidic-salt or its solution, the product of step (A) are formula (4) Compound, antioxidant, catalyst, deionized water add reactor, under nitrogen atmosphere, regulate and control reaction temperature and pressure, needed for being obtained Organophosphors system copolymerization fire-retardant polyamide material.

5. the preparation method according to any one of claim 2-4, in step (B), the polymerized monomer diacid is for oneself Diacid, decanedioic acid, Azelaic Acid, heneicosanedioic acid, dodecanedioic acid, p-phthalic acid, M-phthalic acid, phthalic acid or he Derivant and other aliphatic and aromatic dicarboxylic acid in one or more；Diamidogen is hexamethylene diamine, nonamethylene diamine, the last of the ten Heavenly stems two Amine, hendecane diamidogen, dodecamethylene diamine and aliphatic C₆-C₂₀In imino group diamidogen, aromatic diamine or alicyclic diamine One or more；And binary amidic-salt is hexamethylene adipamide salt, adipyl pentanediamine salt, hexamethylene azelamide salt, the last of the ten Heavenly stems two Acyl hexamethylene diamine salt, decanedioyl octamethylenediamine salt, suberoyl hexamethylene diamine salt, one or more of suberoyl octamethylenediamine salt.

The antioxidant is the compound such as p-phenylenediamine and dihydroquinoline and its derivant, 2,6- di-tert-butyl-4-methy phenols, Double (3,5- di-tert-butyl-hydroxy phenyl) thioethers, four (β-(3,5- di-tert-butyl-hydroxy phenyl) propanoic acid) pentaerythritol ester In one or more；And/or

The catalyst is sodium hypophosphite, toluene sulfonic acide, one or more in new ferrocene chiral polyamide part.

6. the preparation method according to any one of claim 2-5, wherein, in step (B), specifically includes following steps：

A. by polymerized monomer be diacid and diamidogen or binary amidic-salt or its solution, step (A) gained product, catalyst, Antioxidant, deionized water add reactor, and evacuation, inflated with nitrogen are for several times so that initial reaction stage, and in kettle, pressure is 0.1- 0.5MPa；

B. reacting by heating kettle, is warming up to 200-250 DEG C, when pressure is 1.6-2.1MPa, maintains this reaction condition 30-180min；

C. start slow pressure release to normal pressure at 230-280 DEG C, be then evacuated to -0.01 to -0.1MPa, then copolymer-1 0- 180min；

D. nitrogen, discharges material is finally filled with, cooling, pelletizing, is extracted, is dried to obtain final product.

7. preparation method according to claim 6, wherein, in step a, the polymerized monomer diacid and diamidogen or binary acyl The addition of amine salt or its solution is 8-100 times of the flame-retardant monomer quality, preferably 10-40 times, more preferably 12-30 times；Institute The 0.01%-1.0% that catalyst, antioxidant are respectively the diacid and diamidogen or binary amidic-salt or its solution quality is stated, excellent Select 0.05-0.5%, more preferably 0.08-0.2%, more preferably e.g., from about 1/1000；In system, the addition of water is the total matter of reactant The 10-60% of amount, preferably 30-50%.