CN101775138A - Novel polytriazoles imide resin and preparation method thereof - Google Patents

Abstract

The invention discloses a polyimide containing a triazole ring in the main chain structure, that is, polytriazole imide and a preparation method thereof. Firstly, a binary azide compound is designed and synthesized; secondly, a binary acid anhydride and meta Use aminophenylacetylene as raw material to design and synthesize terminal alkynyl imide compounds; thirdly, use terminal alkynyl imide compounds and azide compounds in equimolar amounts to carry out 1,3-dipolar cycloaddition polymerization in a solvent reaction, or adopt thermal polymerization reaction, or adopt catalytic polymerization reaction to synthesize new polytriazole imide; The polytriazole imide resin prepared by the present invention not only has good processability, but also has higher thermal stability, At the same time, it also has good mechanical properties and electrical properties, and reflects the characteristics of high corrosion resistance and high adhesion of polytriazole resins. It has broad application prospects in aviation, aerospace, microelectronics, automobiles, shipbuilding industries and other fields. .

Description

A kind of new polytriazole imide resin and preparation method thereof

【Technical field】

The present invention relates to the technical fields of chemistry, chemical engineering and materials, and relates to a new polytriazole imide resin and its preparation method, specifically, a method of using two-terminal alkynyl imide compounds and diazide compounds via 1 , 3-dipolar cycloaddition polymerization to prepare a new type of polytriazole imide resin.

【Background technique】

In the late 1960s, Baldwin et al. found in their research that compounds with both azido and alkynyl groups in their molecular structures can undergo 1,3-dipolar cycloaddition polymerization reactions to generate 1,4 substitutions and 1,5 Substituted linear triazole resins that form polymers with high thermal stability. In the 1980s, Mock et al. found that the 1,3-dipolar cycloaddition reaction of azide-alkynyl groups only produced 1,4-substituted triazole ring structures when catalyzed by some reagents with amino groups. The former Soviet Union and Beijing Institute of Technology in China used the reaction of azide and alkyne to prepare a new type of energetic adhesive. In 2002, Huang Farong's laboratory of East China University of Science and Technology began to study the reaction of alkyne and azide, and used the thermal reaction of alkyne and azide to prepare polytriazole resin. In the same year, Sharpless et al reported the 1,3-dipolar addition reaction of azide-alkynyl catalyzed by monovalent copper salt (Cu(I)), and found that the catalytic addition reaction rate increased by 10 ⁶ times, and It has stereoselectivity and only generates 1, 4-disubstituted 1, 2, 3-triazole compounds. Sharpless proposed the concept of Click chemistry.

The Click reaction is a simple and efficient synthetic reaction in chemistry. It is a nearly perfect chemical reaction. It is characterized by simple reaction conditions, generally insensitive to water and oxygen, easy access to starting materials and reagents, high yields, and products. Easy to separate. The 1.3-dipolar cycloaddition reaction of azide-alkynyl is a typical Click reaction and has become a hotspot in material science research. Hawker, Sharpless et al took the lead in applying Huisgen1,3-dipolar cycloaddition reaction to the synthesis of dendrimers. Afterwards, polymers with new molecular structures such as linear, cross-linked, star, and hyperbranched were successively synthesized by using the Click reaction. As an important synthetic method, Click reaction is also combined with other polymerization methods, such as living polymerization and atom transfer radical polymerization, in material synthesis, and is widely used in the design and preparation of new polymer materials.

The Huang Farong laboratory of East China University of Science and Technology applied the 1,3-dipolar cycloaddition reaction of azido group and alkynyl group at a lower temperature to the synthesis of polymers containing triazole rings, and successfully developed a 1,4 - Linear, cross-linked curable low temperature curable polytriazole resins of disubstituted and 1,5-disubstituted-1,2,3-triazole rings. The research results show that thermally cross-linked and cured polytriazole resins have excellent processability, thermal properties and mechanical properties. Recently, Tang Benzhong and others also used the non-catalytic cycloaddition reaction of azide and alkyne to prepare a linear polytriazole functional material with a weight average molecular weight of 20,000 to 30,000.

As a rigid aromatic ring, the triazole ring has good heat resistance, thermal oxidation resistance and chemical resistance. The triazole ring has good adhesion to metals and can be widely used as an anti-corrosion coating for metal materials. .

Polyimide material is a kind of polymer material containing five-membered imide ring in the molecular main chain. It not only has good heat resistance, but also has excellent dimensional stability, oxidation stability and chemical corrosion resistance. , radiation resistance, and good mechanical and dielectric properties, so it has outstanding application value and is widely used in aerospace, electrical and electronic, transportation and other fields.

At present, the application forms of polyimide are:

① Film manufacturing. The Kapton film developed by DuPont in the 1960s was one of the earliest products of polyimide; subsequently, the Japanese Unitika company successively developed Upilex-R and Upilex-S films, which have low shrinkage, low thermal expansion coefficient, and low Water absorption, as well as hydrolysis resistance and excellent mechanical properties.

② Paint manufacturing. Used as insulating varnish or high temperature resistant coating.

③Manufacturing of advanced composite materials. As a high-temperature resistant resin-based composite material, it is widely used in structural parts and engine parts in the aerospace industry.

④ fiber manufacturing. The modulus of elasticity of the manufactured fiber is second only to that of carbon fiber, and it is a reinforcing agent for advanced composite materials.

⑤ Manufacture of foam and engineering plastics. The former is used as a heat and sound insulation material that is resistant to high temperature and low temperature, and the latter is mainly used for self-lubricating, sealing, insulating and structural materials.

⑥In addition, as a functional material, polyimide is also widely used in the fields of microelectronic devices, liquid crystal displays, and nonlinear optoelectronic materials.

However, a large number of studies have shown that the molecular chains of polyimide are relatively rigid, the force between molecular chains is very strong, and the molecular chains are tightly packed, which often makes polyimide infusible and insoluble. In response to this shortcoming, a lot of research has been carried out, and various methods have been used to improve the performance of polyimide. In recent years, through the molecular design of monomers, special structural units (such as flexible structural units, large side groups or solvophilic groups, twisted and non-coplanar structures), introduction of aromatic heterocycles, fluorosilicone, etc. have been introduced into the molecular structure. and other elements, or modify polyimide by means of copolymerization. At present, the polyimides that have been researched and developed are:

① Introduce flexible structural units into dianhydride or diamine monomers to improve the fluidity of polyimide molecular chains, or improve the solubility and melting properties of polyimide;

②Introduce twisted and non-coplanar structures into polyimide to distort the formed polyimide molecular chain segments, reduce or destroy the conjugated system of the polyimide molecular main chain, and reduce the intermolecular force , thereby improving the solubility of polyimide;

③Introduce large side groups or solvophilic groups on the molecular main chain to reduce the packing density of polymer molecular chains, so that solvent molecules can easily penetrate, thus having good solubility.

In recent years, the introduction of aromatic heterocyclic structures into the molecular backbone of polymers has become a research hotspot. The introduction of aromatic heterocyclic structural units into the molecular backbone of polyimide can not only significantly improve its processing performance while maintaining its excellent mechanical properties and heat resistance, but also improve its electrical and magnetic properties. At present, the pyridine ring is more frequently introduced into the aromatic heterocycle structure. The pyridine ring is a rigid aromatic heterocyclic molecule with aromaticity, symmetry, basicity and polarity. The research results show that the polyimide with pyridine ring in the main chain not only has excellent thermal stability and chemical stability, but also has good solubility and film-forming properties. The preparation of polyimides containing pyridine rings in the main chain is mainly achieved by designing and synthesizing dianhydride or diamine monomers containing pyridine rings. John et al obtained a dinitro compound containing a pyridine ring through the Claisen-Schmidt reaction, and then obtained a pyridine-containing diamine through Pd/C catalytic hydrogenation reduction. Yanfeng Li of Lanzhou University and others synthesized a series of polyimides containing pyridine rings. However, the synthesis of monomers containing pyridine rings is difficult, the yield is low, and the cost is high, which largely hinders the development of polyimides containing pyridine rings in the main chain.

There are many ways to synthesize polyimide. The polycondensation reaction of aromatic dianhydride and diamine is a general method for preparing polyimide. It often requires high temperature heat treatment to complete its imidization. Most of them are limited to films and coatings. aspects of application. In addition, because the polyamic acid solution is sensitive to temperature during storage, the method of polycondensation reaction is greatly limited. Therefore, the synthesis of melt-processable or soluble polyimide has become the focus of research.

【Content of invention】

The purpose of the present invention is to provide a new polytriazole acid with excellent mechanical properties and heat resistance, greatly improved soluble and fusible processing properties, special properties in electricity and magnetism, and easy processing through molecular design and synthesis. Imine resin; Another object of the present invention is to provide a preparation method of the polytriazole imide resin, thereby ensuring a wider application of polyimide.

For realizing above-mentioned object, the technical scheme that the present invention takes is:

A kind of polytriazole imide resin, its chemical structural formula is:

n=20～100,

In the formula,

In the polytriazole imide resin, the structure of the terminal alkynyl imide compound is as follows:

In described polytriazole imide resin, the structure of azide compound is as follows:

For realizing above-mentioned object, the technical scheme that the present invention takes is:

A kind of preparation method of polytriazole imide resin is characterized in that, polytriazole imide is prepared by the Click chemical cycloaddition polymerization reaction of alkyne-azide with terminal alkynyl imide compound and azide compound , using catalytic polymerization or thermal polymerization, the preparation steps are:

(1) Preparation of azide compounds

Using sodium azide and halogenated hydrocarbons as raw materials, the azide compound is prepared by nucleophilic substitution reaction. The preparation process is as follows: the synthesis of the azide compound is carried out in the solution, and the solvent is selected from N, N'-dimethylformamide ( DMF), benzene, toluene, dimethyl sulfoxide (DMSO), or tetrahydrofuran (THF); add the mixed solvent of toluene and DMF in the reactor, the volume ratio of the two is toluene: DMF=1: 1～2, The amount of addition is 800-1500mL of mixed solvent per mole of halogenated hydrocarbon; add halogenated hydrocarbon, which is chloride, bromide or iodide; the equivalent ratio of reaction raw materials sodium azide to halogenated hydrocarbon is 1.0- 3.0:1.0, the reaction temperature is 20-80°C, the reaction time is 2-10h, and its structural formula is:

in,

(2) Preparation of terminal alkynyl imide compounds

The terminal alkynyl imide compound is synthesized by reacting an acid anhydride with an amine compound with an alkyne group, followed by dehydration and cyclization with acetic anhydride. The preparation process is divided into two steps:

The first step, reacts aromatic acid anhydride and aromatic amine with alkyne group in organic solvent (acetone etc.) to generate amic acid;

The second step is to use acetic anhydride as a dehydrating agent and triethylamine as a catalyst for dehydration and cyclization to generate terminal alkynyl imide compounds;

These operations should be carried out under the protective conditions of inert gas, such as nitrogen, helium or argon, and finally, wash with acetone and purify the prepared terminal alkynyl imide compound. Its structural formula is:

in:

(3) Preparation of polytriazole imide

Carry out 1,3-dipolar cycloaddition polymerization in a solvent with the prepared two-terminal alkynyl imide compound and diazide compound in an equimolar amount, and the polymerization reaction is either a thermal polymerization reaction or a catalytic polymerization reaction ;

Described solvent is N, N'-dimethylformamide (DMF), N, N'-dimethylacetamide (DMAc), dimethylsulfoxide (DMSO) or N-methylpyrrolidone (NMP) one or more of

The thermal polymerization reaction is as follows: adding equimolar two-terminal alkynyl imide compounds and diazide compounds into a three-necked flask, adding a solvent, and preparing a mixed solution with a mass concentration of 5-50% (preferably 15 -30%), after fully stirring, heat up to 70-120°C (preferably 80-100°C), stir and react for 12-48 hours (preferably 24-36 hours), to obtain a polymer solution; after cooling to room temperature, react Pour the solution into ethanol to precipitate to obtain a white product; filter it with suction, wash it with hot ethanol, and dry it in a vacuum oven at 100°C overnight to obtain a polytriazole imide resin;

The catalytic polymerization reaction is as follows: adding equimolar alkynyl imide compounds and diazide compounds into a three-necked flask, adding solvent DMF, DMAc, DMSO or N-methylpyrrolidone, so that the mass concentration of the reactants 5% to 50% (preferably 15% to 30%), after stirring fully, heat up to 20 ~ 80°C (preferably 40°C to 60°C); then add CuSO ₄ 5H ₂ O and sodium ascorbate catalyst, the addition amount is respectively 5% and 10% of the number of moles of the base compound, while adding a triethylamine complexing agent equivalent to the number of moles of the terminal alkynyl imide compound, stirring and reacting at a constant temperature for 2 to 8 hours (preferably 3 to 4 hours), A viscous polymer solution is obtained; after cooling to room temperature, the reaction mixture is poured into deionized water to obtain a fibrous polytriazole imide resin, and simultaneously soaked and washed repeatedly with deionized water to remove the catalyst and triethylamine, Suction filtration, and after washing with hot ethanol, dry overnight in a vacuum oven at 100°C to obtain high molecular weight polytriazole imide, which is then dissolved in dimethylacetamide, dimethyl sulfoxide or N-methylpyrrolidone Reprecipitate and purify in medium, and obtain polytriazole imide resin after drying, and its chemical reaction equation is:

n=20～100,

In the formula:

A kind of new polytriazole imide resin of the present invention has the following advantages:

(1) The triazole ring is introduced into the main chain structure of the polyimide, so that the polytriazole imide resin is soluble and fusible, and has good processability;

(2) It has high thermal stability, its thermal decomposition temperature T _d5 can reach 360 °C, and the glass transition temperature (T _g ) can be above 200 °C;

(3) It has both good mechanical properties and good electrical properties;

(4) It has functional properties such as corrosion resistance and high adhesion, and has broad application prospects in the fields of aviation, aerospace, microelectronics, automobiles, and shipbuilding industries.

The positive effect of the preparation method of a kind of polytriazole imide resin of the present invention is:

(1) Click chemical cycloaddition polymerization reaction conditions are mild and controllable, it can be carried out under simple conditions, it is not sensitive to water and oxygen, and does not need protection such as nitrogen, helium or argon;

(2) The alkynyl-terminated imide compound is easy to prepare, and can be completely imidized at a relatively low temperature, avoiding the high-temperature imidization and side reactions of polyimide synthesis;

(3) The Click chemical cycloaddition reaction is complete and specific, and the addition reaction does not affect other functional groups, and has good compatibility. Through reasonable molecular design, the reaction can be easily introduced into polytriazole imide Sexual active groups, such as carboxyl, hydroxyl, etc.;

(4) No small molecular substances are released during the polymerization process, no side reactions or by-products are produced, and high molecular weight polyimides are easily synthesized.

【Detailed ways】

The preparation method of the present invention is specifically described below through 9 examples, the purpose of which is to better understand the content of the present invention, but the protection scope of the present invention is not limited to the following examples.

According to the preparation steps of the preparation method of a polytriazole imide resin described above, the following experiments and verifications were carried out.

Example 1

(1) Synthesis of 1,4-diazidemethylbenzene (A1)

Add 50mmol of 1,4-dichloromethylbenzene, 150mmol of NaN ₃ , 20ml of toluene and 20ml of DMF into a three-necked flask, heat to 70-75°C under stirring, and react at constant temperature for 3h. After the reaction, cool the reaction product to room temperature. Pour into 200ml of deionized water, stand overnight under freezing conditions to precipitate white flaky crystals, filter, wash the filter cake with deionized water, and dry to obtain a white powdery solid with a yield of 90.0%, mp.26.0～27.5°C .

(2) Synthesis of bis(N-ethynylphenyl)-bisphenol A ether phthalimide (B1)

Add 20mmol of bisphenol A dianhydride (BPADA) and 40mmol of m-aminophenylacetylene into a 250ml four-neck flask equipped with stirring, constant pressure funnel and spherical condenser, add 50ml of acetone as a solvent, heat and reflux for 6 hours and then add 50ml acetic anhydride, and added 75ml of triethylamine as a catalyst, refluxed at 80 ° C for 6 hours, cooled and precipitated after the reaction, washed with acetone, filtered and dried to obtain the product, the yield was 92%; FTIR (cm ^{- 1} ): 3254 (≡CH), 1776 (C=O anti-symmetric stretching), 1714 (C=O symmetrical stretching, imine I), 1384 (CNC, imine II), 748 (C=O); ¹ H -NMR(DMSO): 7.2～8.0(Ar-H), 4.31(≡CH), 1.67(-CH ₃ ), its structural formula is:

(3) Preparation of polytriazole imide PTAI-A1-B1

Add 10mmol of 1,4-diazidemethylbenzene, 10mmol of bis(N-ethynylphenyl)-bisphenol A ether phthalimide and 30ml of DMAc into the reactor, stir well and dissolve to form a transparent Solution, heated up to 60°C, then added catalyst CuSO ₄ 5H ₂ O 0.5mmol, sodium ascorbate 1mmol and complexing agent triethylamine 10mmol, and stirred and reacted at 60°C for 2 hours to obtain a viscous polymer solution; cooling After reaching room temperature, slowly pour the reaction mixture into deionized water to obtain filamentous polytriazole imide, soak and wash it with deionized water three times at the same time, remove the catalyst and triethylamine, suction filter, and wash with hot ethanol, Dry overnight in a vacuum oven at 100°C to obtain white polytriazole imide; then dissolve it in DMAc for reprecipitation purification and dry to obtain polytriazole imide, FTIR (cm ^-1 ): 1777 (C =O anti-symmetric stretching), 1722 (C=O symmetrical stretching, imine I), 1372 (CNC, imine II), 744 (C=O); ¹ H-NMR (DMSO): 8.52 (triazole ring H), 7.2～8.0 (Ar-H), 5.62 (CH ₂ ), 1.68 (-CH ₃ ); its structural formula is:

The number average molecular weight Mn of the obtained polymer: 35500 (GPC), Mw/Mn=2.78; Intrinsic viscosity (0.5g/dl DMAc solution at 30 ℃) 0.42, water absorption rate 1.71%; The amine PTAI-A2-B1 has good solubility and is easily soluble in solvents such as DMF, DMAc, DMSO and NMP at room temperature.

Example 2

(1) Synthesis of 4,4'-diazidomethylbiphenyl (A2)

Add 50mmol of 4,4'-dichloromethylbiphenyl, 150mmol of NaN ₃ , 20ml of benzene and 20ml of DMF into a three-necked flask, heat to 75°C under stirring, and react at constant temperature for 3h. After the reaction, cool the reaction product to room temperature. Pour it into 200ml of deionized water, let stand overnight, a white solid precipitates out, filter, wash the filter cake with deionized water, and dry to obtain a white powdery solid with a yield of 89.0% and a melting point of 67-71°C.

(2) Preparation of polytriazole imide PTAI-A2-B1

Add 10mmol of 4,4'-diazidomethylbiphenyl, 10mmol of bis(N-ethynylphenyl)-bisphenol A ether phthalimide and 40ml of DMAc into the reactor to form a transparent solution. After fully stirring and dissolving, heat up to 60°C, then add catalyst CuSO ₄ 5H ₂ O 0.5mmol, sodium ascorbate 1.0mmol and complexing agent triethylamine 10.0mmol, and stir and react at 60°C for 4 hours to obtain a viscous polymer solution; after cooling to room temperature, slowly pour the reaction mixture into deionized water to obtain filamentous polytriazole imide, soak and wash with deionized water three times at the same time, remove the catalyst and triethylamine, filter with suction, and heat After washing with ethanol, dry overnight in a vacuum oven at 100°C to obtain white biphenyl-type polytriazole imides; then dissolve in DMAc for reprecipitation and purification, and dry to obtain polytriazole imides; FTIR (cm ^-1 ): 1777 (C=O anti-symmetric stretching), 1722 (C=O symmetric stretching, imine I), 1372 (CNC, imine II), 744 (C=O); ¹ H-NMR (DMSO ): 8.52 (H on the triazole ring), 7.2～8.0 (Ar-H), 5.62 (CH ₂ ), 1.67 (-CH ₃ ), its structural formula is:

The number average molecular weight Mn of the polymer obtained: 13000 (GPC), Mw/Mn=1.73; Intrinsic viscosity (0.5g/dl DMAc solution under 30 ℃) 0.36, and its water absorption rate is 1.62%; Polytriazole acid The imine PTAI-A2-B1 is easily soluble in solvents such as DMF, DMAc, DMSO and NMP at room temperature.

Example 3

(1) Synthesis of 4,4'-diazidomethyl diphenyl ether (A3)

Add 50mmol of 4,4'-dichloromethyldiphenyl ether, 150mmol of NaN ₃ , 20ml of toluene and 20ml of DMF into a three-necked flask, heat to 75°C under stirring, and react at constant temperature for 4h. After the reaction, cool the reaction product to room temperature , poured into 200ml of deionized water, let it stand overnight, a white solid was precipitated, filtered, the filter cake was washed with deionized water, and dried to obtain a white powdery solid with a yield of 85.0%.

(2) Preparation of polytriazole imide PTAI-A3-B1

Add 10mmol of 4,4'-diazidomethyl diphenyl ether, 10mmol of bis(N-ethynylphenyl)-bisphenol A ether phthalimide and 40ml of DMAc into the reactor to form a transparent solution , fully stirred and dissolved and heated to 60°C, then added catalyst CuSO ₄ ·5H ₂ O 0.5mmol, sodium ascorbate 1.0mmol and complexing agent triethylamine 10.0mmol, and stirred and reacted at 60°C for 8 hours to obtain viscous Polymer solution; After being cooled to room temperature, the reaction mixture is slowly poured into deionized water to obtain filamentous polytriazole imides; aftertreatment is the same as in Example 2, and drying obtains polytriazole imides; FTIR ( ^{cm- 1} ) with example 2, its structural formula is:

The prepared polytriazole imide PTAI-A3-B1 is soluble in solvents such as DMF, DMAc, DMSO and NMP, the intrinsic viscosity (0.5g/dl DMAc solution at 30°C): 0.30, and the glass transition temperature is 200 °C, 5% thermal weight loss temperature is 350 °C (N ₂ ).

Example 4

(1) Synthesis of bis(N-ethynylphenylphthalimide) ether (B2)

Add 12.4g (0.04mol) of 4,4'-oxydiphthalic anhydride and 11.23g (0.096mol) of m-aminophenylacetylene into a 250ml four-necked flask equipped with stirring, constant pressure funnel and spherical condenser, and add 100ml of acetone was used as the solvent, heated and refluxed for 4 hours, then added 50ml of acetic anhydride, and 75ml of triethylamine was added as a catalyst, refluxed at 80°C for 4 hours, cooled after the reaction, added to 200ml of ethanol for precipitation, suction filtration, Wash with acetone, filter with suction, and dry to obtain the product, stir at low temperature (in an ice-water bath) for 30 minutes, filter with suction to obtain a white product, wash with ethanol, and dry in vacuo. The yield is 96%; FTIR (cm ^-1 ): 3254 (≡CH), 1776 (C=O anti-symmetric stretching), 1714 (C=O symmetrical stretching, imine I), 1384 (CNC, imine II), 1230 (-O-), 748 (C ＝O); ¹ H-NMR (DMSO): 7.1～8.0 (Ar-H), 4.32 (≡CH), its structural formula is:

(2) Preparation of polytriazole imide PTAI-A1-B2

Add 10mmol of 1,4-diazidemethylbenzene, 10mmol of bis(N-ethynylphenylphthalimide) ether and 30ml of DMSO into the reactor to form a turbid mixed solution, which is heated up to 60°C, then add catalyst CuSO ₄ ·5H ₂ O 0.5mmol, sodium ascorbate 1.0mmol and complexing agent triethylamine 10.0mmol, and stir and react at 60°C for 4 hours to obtain a viscous polymer solution; cool to room temperature Finally, slowly pour the reaction mixture into 500mL of deionized water to obtain filamentous polytriazole imide, soak and wash it with deionized water three times at the same time, remove the catalyst and triethylamine, filter with suction, and wash with hot ethanol , dried overnight in a vacuum oven at 100°C to obtain light yellow polytriazole imide; then dissolved in DMAc for reprecipitation purification and drying to obtain polytriazole imide; FTIR (cm ^-1 ): 1777 (C=O anti-symmetric stretching), 1722 (symmetric stretching of C=O, imine I), 1372 (CNC, imine II), 1230 (-O-), 744 (C=O); ¹ H-NMR (DMSO): 8.52 (H on the triazole ring), 7.2～8.0 (Ar-H), 5.61 (-CH ₂ ); its structural formula is:

The prepared polytriazole imide is soluble in solvents such as DMF, DMAc, DMSO and NMP at room temperature, the intrinsic viscosity (0.5g/dl DMAc solution at 30°C) is 0.46, and the glass transition temperature is 230°C, 5 The % thermal weight loss temperature is 360°C (N ₂ ).

Example 5

Preparation of polytriazole imide PTAI-A2-B2

Add 10mmol of 4,4'-diazidomethylbiphenyl, 10mmol of bis(N-ethynylphenylphthalimide) ether and 50ml of NMP into the reactor to form a turbid mixed solution. After fully stirring Heat up to 60°C, then add catalyst CuSO ₄ ·5H ₂ O 0.5mmol, sodium ascorbate 1mmol and complexing agent triethylamine 10mmol, and stir and react at 60°C for 4 hours to obtain a viscous polymer solution; cool to room temperature Finally, slowly pour the reaction mixture into 500ml of deionized water to obtain filamentous polytriazole imide, soak and wash it with deionized water three times at the same time, remove the catalyst and triethylamine, filter it with suction, and wash it with hot ethanol , dried overnight in a vacuum oven at 100°C to obtain pale yellow polytriazole imide; then dissolved in NMP for reprecipitation and purification, and dried to obtain polytriazole imide; FTIR (cm ^-1 ): 1777 (C =O anti-symmetric stretching), 1724 (symmetric stretching of C=O, imine I), 1378 (CNC, imine II), 1232 (-O-), 754 (C=O); ¹ H-NMR (DMSO ): 8.5 (H on the triazole ring), 7.2～8.0 (Ar-H), 5.6 (-CH ₂ ); its structural formula is:

The prepared polytriazole imide is soluble in solvents such as DMF, DMAc, DMSO and NMP at room temperature, the intrinsic viscosity (0.5g/dl DMAc solution at 30°C) is 0.35, and the glass transition temperature is 210°C, 5 The % thermal weight loss temperature is 358°C (N ₂ ).

Example 6

(1) Synthesis of bis(N-ethynylphenylphthalimide)methanone (B3)

Add 12.4g (0.04mol) of 3,3',4,4'benzophenone tetracarboxylic dianhydride and 11.23g of m-aminophenylacetylene into a 250ml four-neck flask equipped with stirring, constant pressure funnel and spherical condenser (0.096mol), add 100ml of acetone as a solvent, heat and reflux for 4 hours, then add 50ml of acetic anhydride, and add 75ml of triethylamine as a catalyst, reflux at 80°C for 4 hours, cool after the reaction, and add to 200ml of ethanol Precipitation, suction filtration, washing with acetone, suction filtration, and drying to obtain the product with a yield of 96%; FTIR (cm ^-1 ): 3267 (≡CH), 1778 (C=O anti-symmetric stretching), 1720 (C =O, symmetrical stretching I), 1640 (keto group C=O), 1384 (CNC, II), 748 (C=O); ¹ H-NMR: 7.2～8.0 (Ar-H), 4.3 (≡CH) , whose structure is:

(2) Preparation of polytriazole imide PTAI-A1-B3

Add 10mmol of 1,4-diazidemethylbenzene, 10mmol of bis(N-ethynylphenylphthalimide)methanone and 30ml of DMAc into the reactor to form a turbid mixed solution, stir well and then raise the temperature to 60°C, then add catalyst CuSO ₄ 5H ₂ O 0.5mmol, sodium ascorbate 1mmol and complexing agent triethylamine 10mmol, and stir and react at 60°C for 3 hours to obtain a viscous polymer solution; the post-treatment method is the same as The same as in Example 4, the light yellow polytriazole imide was obtained; FTIR (cm ^-1 ): 1779 (C=O anti-symmetric stretching), 1725 (C=O symmetrical stretching, imine I), 1640 (ketone C=O), 1374 (CNC, imine II), 752 (C=O); ¹ H-NMR (DMSO): 8.5 (H on the triazole ring), 7.2～8.0 (Ar-H), 5.6 (-CH ₂ ); its structural formula is:

The prepared polytriazole imide is soluble in solvents such as DMF, DMAc, DMSO and NMP, the intrinsic viscosity (0.5g/dl DMAc solution at 30°C) is 0.40, the glass transition temperature is 230°C, and 5% thermal weight loss The temperature was 355°C (N ₂ ).

Example 7

Preparation of polytriazole imide PTAI-A2-B3

The preparation process is similar to the preparation of polytriazole imide PTAI-A1-B3 in Example 6, but stirred and reacted at 60°C for 4 hours to obtain light yellow polytriazole imide; FTIR (cm ^-1 ) is the same as Embodiment 6; Its structural formula is:

The prepared polytriazole imide is soluble in solvents such as DMF, DMAc, DMSO and NMP, the intrinsic viscosity (0.5g/dl DMAc solution at 30°C) is 0.30, the glass transition temperature is 235°C, and 5% thermal weight loss The temperature was 360°C (N ₂ ).

Example 8

(1) Synthesis of bis(N-ethynylphenylphthalimide) hexafluoroisopropane (B4)

Add 40mmol of 4,4'-hexafluoroisopropylidene phthalic anhydride, 96mmol of m-aminophenylacetylene in a 250ml four-neck flask equipped with stirring, constant pressure funnel and spherical condenser, add 100ml of acetone as a solvent, and heat After refluxing for 4 hours, add 50ml of acetic anhydride, and add 75ml of triethylamine as a catalyst, reflux at 80°C for 4 hours, add to 500ml of deionized water after the reaction, stir and precipitate, and filter with suction to obtain a white product, which is then used Washed with ethanol and dried in vacuum to obtain the product with a yield of 90%; FTIR (cm ^-1 ): 1782 (C=O anti-symmetric stretching), 1724 (C=O symmetrical stretching, imine I), 1384 (CNC, II imine), 1136(-CF ₃ ), 753(C=O); ¹ H-NMR(DMSO): 7.2～8.0(Ar-H), 4.30(≡CH), its structural formula is:

(2) Preparation of polytriazole imide PTAI-A1-B4

Add 10mmol of 1,4-diazidomethylbenzene, 10mmol of bis(N-ethynylphenylphthalimide)hexafluoroisopropane and 30ml of DMF into the reactor to form a transparent solution, fully stir to dissolve After heating up to 60°C, add catalyst CuSO ₄ ·5H ₂ O 0.5mmol, sodium ascorbate 1mmol and complexing agent triethylamine 10mmol, and stir and react at 60°C for 4 hours to obtain a viscous polymer solution, which was cooled to After room temperature, slowly pour the reaction mixture into 500mL of deionized water to obtain filamentous polytriazole imide, soak and wash it with deionized water three times at the same time, remove the catalyst and triethylamine, filter with suction, and wash with hot ethanol Dry overnight in a vacuum oven at 100°C to obtain white polytriazole imide, which is then dissolved in DMF for reprecipitation and purification, and dried to obtain polytriazole imide; FTIR (cm ^-1 ): 1782 (C= O anti-symmetric stretching), 1724 (symmetric stretching of C=O, imine I), 1375 (CNC, imine II), 1136 (-CF ₃ ), 752 (C=O); ¹ H-NMR (DMSO) : 8.53 (H on the triazole ring), 7.2～8.0 (Ar-H), 5.61 (-CH ₂ ), its structural formula is:

The prepared polytriazole imide is soluble in solvents such as DMF, DMAc, DMSO and NMP, the intrinsic viscosity (0.5g/dl DMAc solution at 30°C) is 0.30, the glass transition temperature is 235°C, and 5% thermal weight loss The temperature was 360°C (N ₂ ).

Example 9

Preparation of polytriazole imide PTAI'-A1-B1 by thermal polymerization

Add 10mmol of 1,4-diazidemethylbenzene, 10mmol of bis(N-ethynylphenyl)-bisphenol A ether phthalimide and 30ml of DMAc into the reactor, stir well and dissolve to form a transparent solution, heated to 100°C, and stirred and reacted at 100°C for 24 hours to obtain a polymer solution; after cooling to room temperature, the reaction mixture was poured into 200ml of ethanol to precipitate to obtain a white product, which was filtered by suction and washed with hot ethanol , dried overnight in a vacuum oven at 100°C to obtain polytriazole imide; FTIR (cm ^-1 ): 1777 (C=O anti-symmetric stretching), 1722 (C=O symmetrical stretching, imine I), 1372 (CNC, imine II), 1150 (-CH ₃ ), 744 (C=O); ¹ H-NMR (DMSO): 8.4-8.5 (H on the triazole ring), 7.2-8.0 (Ar-H) , 5.62(CH ₂ ), 1.68(-CH ₃ ), its structural formula is:

The obtained polytriazole imide PTAI'-A1-B1 has good solubility, and is easily soluble in solvents such as DMF, DMAc, DMSO and NMP at room temperature; solution) 0.28; the glass transition temperature is 180°C, and the 5% thermal weight loss temperature is 360°C (N ₂ ).

Claims (7)

1. a polytriazole imide resin, is characterized in that, its chemical structural formula is:

n=20～100, In the formula,

one of

one of

One of. 2. polytriazole imide resin according to claim 1, is characterized in that, wherein the chemical structure of terminal alkynyl imide compound is:

one of One of. 3. polytriazole imide resin according to claim 1, is characterized in that, wherein the chemical structure of azide compound is:

One of. 4. a kind of preparation method of polytriazole imide resin as claimed in claim 1 is characterized in that, with terminal alkynyl imide compound and azide compound by the Click chemical cycloaddition polymerization of alkyne-azide Reaction prepares polytriazole imide, and its preparation steps are: (1) Preparation of azide compounds Using sodium azide and halogenated hydrocarbons as raw materials, the azide compound is prepared by nucleophilic substitution reaction. The preparation process is as follows: the synthesis of the azide compound is carried out in the solution, and the solvent is selected from N, N'-dimethylformamide ( DMF), benzene, toluene, dimethyl sulfoxide (DMSO), or tetrahydrofuran (THF); add the mixed solvent of toluene and DMF in the reactor, the volume ratio of the two is toluene: DMF=1: 1～2, The amount of addition is 800-1500mL of mixed solvent per mole of halogenated hydrocarbon; add halogenated hydrocarbon, which is chloride, bromide or iodide; the feed ratio (equivalent ratio) of the reaction raw material sodium azide to halogenated hydrocarbon 1.0～3.0:1.0, the reaction temperature is 20～80°C, the reaction time is 2～10h, and its structural formula is:

in,

one of (2) Preparation of terminal alkynyl imide compounds The terminal alkynyl imide compound is synthesized by reacting an acid anhydride with an amine compound with an alkyne group, followed by dehydration and cyclization with acetic anhydride. The preparation process is divided into two steps: The first step, reacts aromatic acid anhydride and aromatic amine with alkyne group in organic solvent (acetone etc.) to generate amic acid; The second step is to use acetic anhydride as a dehydrating agent and triethylamine as a catalyst for dehydration and cyclization to generate terminal alkynyl imide compounds; Finally, it is washed with acetone and purified to obtain a terminal alkynyl imide compound, whose structural formula is:

in:

one of

one of (3) Preparation of polytriazole imide Carry out 1,3-dipolar cycloaddition polymerization reaction in solvent with prepared two-terminal alkynyl imide compound and diazide compound in equimolar amount, polymerization reaction or thermal polymerization reaction; described solvent is One or more of N, N'-dimethylformamide, N, N'-dimethylacetamide, dimethyl sulfoxide or N-methylpyrrolidone; the thermal polymerization reaction is: Add moles of two-terminal alkynyl imide compound and diazide compound into a three-necked flask, add a polar solvent, and prepare a mixed solution with a mass concentration of 5-50%. After stirring fully, the temperature is raised to 70-120°C. Stir the reaction for 12 to 48 hours to obtain a polymer solution; after cooling to room temperature, pour the reaction solution into ethanol to precipitate to obtain a white product; filter with suction, wash with hot ethanol, and dry overnight in a vacuum oven at 100°C to obtain a polymer Triazole imide resin, its structural formula is:

In the formula:

one of one of

One of. 5. the preparation method of polytriazole imide resin according to claim 4 is characterized in that, in the thermal polymerization reaction of preparing polytriazole imide, the mass concentration of the mixed solution of preparation is 15～30% , after sufficient stirring, the temperature is raised to 80-100°C, and the reaction is stirred for 24-36 hours to obtain a polymer solution. 6. the preparation method of polytriazole imide resin according to claim 4 is characterized in that, the polymerization reaction of preparation polytriazole imide adopts catalytic polymerization reaction, and described catalytic polymerization reaction is: equimolar Add several alkynyl imide compounds and diazide compounds into a three-necked flask, add solvent DMF, DMAc, DMSO or N-methylpyrrolidone, so that the mass concentration of the reactant reaches 5-50%, after stirring fully, heat up to 20-80°C, then add CuSO ₄ 5H ₂ O and sodium ascorbate catalyst, the addition amount is respectively 5% and 10% of the moles of the alkynyl compound, and at the same time add three Ethylamine complexing agent, stirred and reacted at constant temperature for 2 to 8 hours to obtain a viscous polymer solution; after cooling to room temperature, pour the reaction mixture into deionized water to obtain fibrous polytriazole imide resin. Soak and wash repeatedly with deionized water to remove the catalyst and triethylamine, filter with suction, wash with hot ethanol, and dry in a vacuum oven at 100°C overnight to obtain high molecular weight polytriazole imide, which is then dissolved in dimethyl Acetamide, dimethyl sulfoxide or N-methylpyrrolidone reprecipitation and purification, after drying to obtain polytriazole imide resin. 7. the preparation method of polytriazole imide resin according to claim 6 is characterized in that, in the catalytic polymerization reaction of preparing polytriazole imide, reactant mass concentration is 15～30%, stirs fully Afterwards, the temperature is raised to 40-60° C.; the reaction time is 3-4 hours under constant temperature, and a viscous polymer solution is obtained.