Phosphorylated polyphenyl ether and method for preparing the same

Abstract

The present application relates to the technical field of polyphenyl ether, and particularly relates to a phosphonated polyphenyl ether and a preparation method thereof.The phosphonated polyphenyl ether provided by the present application has a structure shown in formula 1; the content of P element in the phosphonated polyphenyl ether is 0.5-5 wt%.The phosphonated polyphenyl ether is obtained by phosphonating modification of polyphenyl ether, and the phosphonated polyphenyl ether can achieve UL-94 V-0 level of flame retardant effect under the condition of low P element content.The present application provides a preparation method of the phosphonated polyphenyl ether, and the phosphonated polyphenyl ether can be prepared by adopting dimethyl methylphosphonate to perform nucleophilic substitution reaction on brominated polyphenyl ether.Compared with modification of polyphenyl ether by using expensive DOPO, the dimethyl methylphosphonate used in the present application is much cheaper, and the production cost is greatly reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of polyphenyl ether, and particularly relates to a phosphonated polyphenyl ether and a preparation method and application thereof. BACKGROUND

[0002] Polyphenyl ether (PPO) is a thermoplastic engineering plastic with excellent performance, and has the advantages of small density, non-toxicity, good creep resistance, low molding shrinkage, high glass transition temperature (Tg), good electrical properties and the like. The high creep resistance is the most prominent feature of polyphenyl ether, and therefore polyphenyl ether is particularly suitable for making industrial structural parts that bear long-term load. However, polyphenyl ether also has some shortcomings, such as poor flame retardancy, which affects the popularization and application of polyphenyl ether.

[0003] In the related art, different phosphorus content phosphonated polyphenyl ethers are prepared by brominating polyphenyl ether and modifying the brominated polyphenyl ether with 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO). Compared with pure polyphenyl ether, the phosphonated polyphenyl ether has higher solubility and better flame retardancy. However, the preparation method uses DOPO with high cost, and is not suitable for mass production of enterprises.

[0004] Therefore, there is an urgent need to develop a low-cost modified polyphenyl ether material that can achieve UL94 V-0 level flame retardant effect. SUMMARY

[0005] Therefore, the purpose of the present application is to provide a phosphonated polyphenyl ether and a preparation method and application thereof. The phosphonated polyphenyl ether has low cost and can achieve UL94 V-0 level flame retardant effect.

[0006] In order to achieve the above-mentioned purpose of the application, the present application provides the following technical solutions:

[0007] The present application provides a phosphonated polyphenyl ether having the structure shown in formula 1:

[0008]

[0009] The content of P element in the phosphonated polyphenyl ether is 0.5-5 wt%.

[0010] The present application provides a preparation method of the phosphonated polyphenyl ether described in the above-mentioned solution, which comprises the following steps: mixing brominated polyphenyl ether having the structure shown in formula 2 and dimethyl methylphosphonate, and performing nucleophilic substitution reaction to obtain the phosphonated polyphenyl ether.

[0011] The bromination degree of the brominated polyphenyl ether is 4-16 wt%;

[0012] The molar ratio of the brominated polyphenyl ether to dimethyl methylphosphonate is 1.1-10:1;

[0013]

[0014] Preferably, the temperature of the nucleophilic substitution reaction is 160-200℃.

[0015] Preferably, the time of the nucleophilic substitution reaction is 9-12h.

[0016] Preferably, the nucleophilic substitution reaction is carried out under the condition of a protective gas.

[0017] Preferably, after the nucleophilic substitution reaction is completed, the obtained mixture is added into ethanol to precipitate the product, and the obtained precipitate is washed with water and dried to obtain the phosphonated polyphenyl ether.

[0018] Preferably, the preparation of the brominated polyphenyl ether comprises: mixing polyphenyl ether, N-bromosuccinimide, an azo initiator and a polar organic solvent to carry out a bromination reaction to obtain the brominated polyphenyl ether.

[0019] Preferably, the molar ratio of the polyphenyl ether and the N-bromosuccinimide is 1:(0.09-0.3).

[0020] Preferably, the temperature of the bromination reaction is 130-160℃, and the time is 3-6h.

[0021] The application provides an application of the phosphonated polyphenyl ether in a flame retardant.

[0022] The application provides a phosphonated polyphenyl ether having a structure shown in formula 1; the content of P element in the phosphonated polyphenyl ether is 0.5-5wt%. The phosphonated polyphenyl ether is obtained by phosphonating modification of polyphenyl ether, and the phosphonated polyphenyl ether can achieve the flame-retardant effect of UL-94 V-0 level under the condition of a low P element content.

[0023] The application provides a preparation method of the phosphonated polyphenyl ether. The phosphonated polyphenyl ether is prepared by using dimethyl methylphosphonate to carry out a nucleophilic substitution reaction on the brominated polyphenyl ether. Compared with the modification of polyphenyl ether by using DOPO (expensive, 100 yuan / kg), the dimethyl methylphosphonate used in the application has a price of 15-20 yuan / kg, which greatly reduces the production cost. Moreover, the application does not need to use a catalyst.

[0024] In addition, the nucleophilic substitution reaction time of the application is at most 12h, which is greatly shortened compared with the modification by using DOPO (the time is 24h), and the production cost is further reduced. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 PPO 1 HNMR spectrum;

[0026] Figure 2 The infrared spectrum of brominated PPO-1 is as follows: 1 H NMR spectrum;

[0027] Figure 3 The infrared spectrum of phosphated PPO-1 is as follows: 1 H NMR spectrum;

[0028] Figure 4 The infrared spectrum of brominated PPO-1 is as follows:

[0029] Figure 5 The infrared spectrum of phosphated PPO-1 is as follows. DETAILED DESCRIPTION

[0030] The present application provides a phosphated polyphenylene ether, having a structure shown in formula 1:

[0031]

[0032] The content of P element in the phosphated polyphenylene ether is 0.5-5wt%.

[0033] In the present application, the subscripts a and b in formula 1 respectively represent the number of corresponding units, and the present application does not make special requirements on the specific values of a and b, as long as the content of P element in the phosphated polyphenylene ether is 0.5-5wt%.

[0034] In specific embodiments, the content of P element in the phosphated polyphenylene ether can be 0.5wt%, 1wt%, 1.5wt%, 2wt%, 2.5wt%, 3wt%, 3.5wt%, 4wt%, 4.5wt% or 5wt%.

[0035] The present application obtains a phosphated polyphenylene ether by phosphating modification of polyphenylene ether, which can achieve UL-94 V-0 level of flame retardant effect under the condition of low content of P element.

[0036] The present application provides a preparation method of the phosphated polyphenylene ether described in the above scheme, comprising the following steps: mixing brominated polyphenylene ether having a structure shown in formula 2 and dimethyl methylphosphonate to perform nucleophilic substitution reaction, to obtain the phosphated polyphenylene ether;

[0037] The bromination degree of the brominated polyphenylene ether is 4-16wt%;

[0038] The molar ratio of the brominated polyphenylene ether and dimethyl methylphosphonate is 1.1-10:1;

[0039]

[0040] In the present application, the preparation method of the brominated polyphenylene ether preferably comprises the following steps:

[0041] The polyphenylene ether, N-bromosuccinimide, azo initiator and polar organic solvent are mixed to carry out bromination reaction, and the brominated polyphenylene ether is obtained.

[0042] In the present application, the molar ratio of the polyphenylene ether and N-bromosuccinimide (NBS) is preferably 1:(0.09-0.3), and in specific embodiments, it can be 1:0.09, 1:0.1, 1:0.15, 1:0.2, 1:0.25 or 1:0.3.

[0043] In the present application, the azo initiator preferably includes azobisisobutyronitrile (AIBN), and the polar organic solvent preferably includes chlorobenzene. The mass of the azo initiator is preferably 1-5% of the mass of the polyphenylene ether, and in specific embodiments, it can be 1%, 2%, 3%, 4% or 5%. The present application does not have special requirements for the amount of the polar organic solvent, which can only ensure that the bromination reaction is carried out.

[0044] In the present application, the bromination reaction is preferably carried out under the condition of a protective gas, and the protective gas is preferably argon or nitrogen. In the present application, the temperature of the bromination reaction is preferably 130-160°C, and the time is preferably 3-6h. In specific embodiments, the temperature of the bromination reaction can be 130°C, 140°C, 150°C or 160°C, and the time of the bromination reaction can be 3h, 4h, 5h or 6h. The present application preferably carries out the bromination reaction under reflux conditions.

[0045] After the bromination reaction is completed, the present application preferably cools the obtained mixture to room temperature, then pours it into n-hexane to make the product precipitate and separate out, filters, washes with ethanol and then dries to obtain the brominated polyphenylene ether.

[0046] In the present application, when AIBN is used as the initiator, the reaction temperature is 130°C, and the reaction time is 4h, the equation of the bromination reaction is as follows:

[0047]

[0048] In the present application, the bromination degree of the brominated polyphenylene ether is 4-16wt%, and in specific embodiments, it can be 4wt%, 6wt%, 8wt%, 10wt%, 12wt%, 14wt% or 16wt%.

[0049] In the present application, the definition of the bromination degree is that the mass of the brominated polyphenylene ether unit accounts for the mass percentage of the polyphenylene ether.

[0050] After the brominated polyphenylene ether is obtained, the present application mixes the brominated polyphenylene ether and dimethyl methylphosphonate to carry out nucleophilic substitution reaction, and the phosphonated polyphenylene ether is obtained.

[0051] In the present application, the molar ratio of the brominated polyphenyl ether and dimethyl methylphosphonate is preferably 1.1-10:1; in specific embodiments it can be 1.1:1, 2:1, 3:1, 4:1, 6:1, 8:1 or 10:1.

[0052] In the present application, the temperature of the nucleophilic substitution reaction is preferably 160-200°C, and the time is preferably 9-12h. In specific embodiments, the temperature of the nucleophilic substitution reaction can be 160°C, 170°C, 180°C, 190°C or 200°C; the time of the nucleophilic substitution reaction can be 9h, 10h, 11h or 12h. In the present application, the nucleophilic substitution reaction is preferably carried out under the condition of a protective gas, which is preferably nitrogen or argon.

[0053] In the present application, the equation of the nucleophilic substitution reaction is as follows:

[0054]

[0055] After the nucleophilic substitution reaction is completed, the present application preferably further comprises adding the obtained mixture into ethanol to precipitate the product, washing the obtained precipitate with water and drying to obtain the phosphonated polyphenyl ether.

[0056] Compared with the modification of polyphenyl ether using expensive DOPO, the dimethyl methylphosphonate used in the present application is low in price, greatly reducing the production cost. Moreover, the present application does not need to use a catalyst.

[0057] The present application provides the use of the phosphonated polyphenyl ether described in the above scheme or prepared by the preparation method described in the above scheme as a flame retardant.

[0058] The phosphonated polyphenyl ether and the preparation method thereof provided by the present application will be described in detail below in conjunction with examples, but they should not be understood as limiting the scope of protection of the present application.

[0059] Example 1

[0060] PPO 10.0g (repeating unit: 82.54mmol), NBS 1.468g (8.254mmol), AIBN 0.20g and chlorobenzene 200mL were added into a round-bottom glass bottle equipped with a nitrogen inlet, a condenser and a magnetic stirrer. The reaction mixture was heated to reflux temperature 160°C under the condition of nitrogen, and kept at this temperature for 4h. Then the reaction mixture was cooled to room temperature, poured into 500mL of n-hexane to precipitate the product. The precipitate was filtered, washed with ethanol, and then dried in a vacuum drying oven at 100°C to obtain a brominated polyphenyl ether, denoted as brominated PPO-1.

[0061] Brominated PPO-1 6.0 g and dimethyl methylphosphonate (DMMP) 25 g (200 mmol) were introduced into a round bottom flask equipped with a nitrogen inlet and a magnetic stirrer. The reaction mixture was stirred at 180°C for 12 h. Then the reaction mixture was cooled to room temperature, the product was precipitated into 150 mL of ethanol, washed with distilled water, and dried in a vacuum oven at 100°C. The phosphonated product was named phosphonated PPO-1, and the phosphorus content was determined to be 0.67 wt% by nuclear magnetic resonance integration area analysis.

[0062] Examples 2-3

[0063] The preparation method was the same as Example 1, except that the amount of raw materials was different.

[0064] The amount of raw materials and product of Examples 1-3 are shown in Table 1 and Table 2.

[0065] Table 1 Preparation of brominated polyphenylene oxide raw materials and bromination degree

[0066]

[0067]

[0068] Table 2 Preparation of phosphonated polyphenylene oxide raw materials and phosphorus content

[0069] Brominated polyphenylene ether DMMP Molar ratio of brominated polyphenylene ether to DMMP Phosphorus content Phosphorylated polyphenylene ether name Brominated PPO-1 6g 25g 2:1 0.67 wt% Phosphorylated PPO-1 Brominated PPO-2 6g 25g 4:1 2 wt% Phosphorylated PPO-2 Brominated PPO-3 6g 25g 8:1 4 wt% Phosphorylated PPO-3

[0070] Structure test:

[0071] Nuclear magnetic resonance measurements were performed on PPO, brominated PPO-1 and phosphonated PPO-1 using a nuclear magnetic resonance instrument in deuterated chloroform, and the results are shown in Figures 1-3 wherein, Figure 1 is the 1 HNMR spectrum of PPO; Figure 2 is the 1 HNMR spectrum of brominated PPO-1; Figure 3 is the 1 HNMR spectrum of phosphonated PPO-1. From the 1 HNMR spectrum of PPO and brominated PPO-1, it can be seen that 7.25 ppm is the solvent peak of deuterated chloroform, and brominated PPO-1 has CH2Br absorption at 2.77 ppm and 1.55 ppm. The bromination rate calculated from the signal integration area CH2 / ArH ratio is 4.3 wt%. From the comparison spectrum of brominated PPO-1 and phosphonated PPO-1, it can be seen that the methylene absorption rate of CH2-Br changes from 2.77 ppm to 3.7-3.75 ppm of CH2-P. The AreH signal produced by the benzene ring is observed at 6-7 ppm, which proves the successful nucleophilic substitution of dimethyl methylphosphonate.

[0072] The infrared test was performed on brominated PPO-1 and phosphated PPO-1, and the results are shown in Figure 4 and Figure 5 The infrared spectra of brominated PPO-1 Figure 4 ) and phosphated PPO-1 Figure 5 ) can be seen that the P=O stretching vibration appears at 1310 cm -1 ; there is a sharp band at 850 cm -1 , which is the stretching vibration of phenyl phosphorus; new vibration peaks appear at 2305-3300 cm -1 , which is confirmed by the nuclear magnetic spectrum, proving the successful preparation of phosphated polyphenyl ether.

[0073] Performance test:

[0074] The flame retardancy of phosphated polyphenyl ether was determined by UL94 VTM vertical experiment, each sample was ignited twice, after the first ignition, the second time was recorded by continuing to ignite on the burned sample. The test results are shown in Table 3.

[0075] Table 3 Flame retardant properties of examples and PPO

[0076] Sample name Phosphorus content First burn time (s) Second burn time (s) UL-94 rating PPO 0 10.6 2.3 V-1 Phosphorylated PPO-1 0.67 wt% 2.7 1.2 V-0 Phosphorylated PPO-2 2 wt% 1.3 0.4 V-0 Phosphorylated PPO-3 4 wt% 1 0.1 V-0

[0077] As can be seen from Table 3, phosphorus has good flame retardancy, and phosphated polyphenyl ether with a phosphorus content as low as 1.0 wt% can achieve UL-94 V-0 level.

[0078] Comparative examples 1-3

[0079] To explore the effect of different reactants on the flame retardancy of phosphated polyphenyl ether:

[0080] The difference from example 1 is that dimethyl methylphosphonate is replaced by equimolar amount of trimethyl phosphate, triethyl phosphate and triphenyl phosphate, respectively, and the specific reaction conditions and yield of phosphated polyphenyl ether are shown in Table 4.

[0081] Table 4 Reaction conditions and yield and flame retardant properties of example 1 and comparative examples 1-3

[0082] Number Reactant 1 Reactant 2 Molar ratio of reactants Yield UL-94 rating Comparative Example 1 Brominated PPO-1 Trimethyl phosphate 2:1 - - Comparative Example 2 Brominated PPO-1 Triethyl phosphate 2:1 - - Comparative Example 3 Brominated PPO-1 Triphenyl phosphate 2:1 25％ V-1 Example 1 Brominated PPO-1 Dimethyl methylphosphonate 2:1 95％ V-0

[0083] As can be seen from the results in Table 4, trimethyl phosphate, triethyl phosphate and brominated polyphenyl ether do not react, triphenyl phosphate can react, but the yield is low, and the flame retardant performance does not reach V0 level through flame retardant test, and triphenyl phosphate has been officially listed in the SVHC candidate substance list.

[0084] The above merely describes the preferred embodiments of the present application, and it should be pointed out that, for those skilled in the art, several improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be considered as falling within the protection scope of the present application.

Claims

1. A method for preparing phosphorylated polyphenylene ether, characterized by, The method comprises the following steps: mixing brominated polyphenyl ether with the structure shown in formula 2 and dimethyl methylphosphonate, and performing nucleophilic substitution reaction to obtain the phosphonated polyphenyl ether; The bromination degree of the brominated polyphenyl ether is 4-16 wt%. The molar ratio of the brominated polyphenyl ether and dimethyl methylphosphonate is 1.1-10:

1. The content of P element in the phosphonated polyphenyl ether is 0.5-5 wt%.

2. The production method according to claim 1, characterized by, The temperature of the nucleophilic substitution reaction is 160-200℃.

3. The production method according to claim 1 or 2, characterized by, The time of the nucleophilic substitution reaction is 9-12h.

4. The production method according to claim 1 or 2, characterized by, The nucleophilic substitution reaction is performed under the condition of passing protective gas.

5. The preparation method according to claim 1, characterized in that, After the nucleophilic substitution reaction is completed, the obtained mixture is added into ethanol to precipitate the product, the obtained precipitate is washed with water and dried to obtain the phosphonated polyphenyl ether.

6. The method of claim 1, wherein, The preparation of the brominated polyphenyl ether comprises the following steps: mixing polyphenyl ether, N-bromosuccinimide, azo initiator and polar organic solvent, and performing bromination reaction to obtain the brominated polyphenyl ether.

7. The production method according to claim 6, wherein The molar ratio of the polyphenyl ether and N-bromosuccinimide is 1:(0.09-0.3).

8. The preparation method according to claim 6, characterized in that, The temperature of the bromination reaction is 130-160℃, and the time is 3-6h.

9. Application of the phosphonated polyphenyl ether prepared by the preparation method in any one of claims 2-8 as a flame retardant.

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