CN107151320A - A kind of method for preparing branching type aryl s-triazine structure o-phthalonitrile resin - Google Patents

Abstract

The invention discloses a method for preparing a branched aryl-s-triazine structure phthalonitrile resin, which belongs to the field of preparation of novel high-temperature-resistant polymer materials. The invention obtains a novel branched phthalonitrile structure by introducing a branched structure combined with a rigid aryl-s-triazine ring structure. The branched phthalonitrile resin containing aryl-s-triazine contains aryl-s-triazine and phthalonitrile with excellent heat resistance. While introducing rigid groups, the branched structure is used to increase cross-linking Density, which can not only improve heat resistance but also have excellent thermal stability. The glass transition temperature T _g can reach 480°C, and the thermal decomposition temperature T _5% can reach up to 581°C. As a new type of branched phthalonitrile, it expands the application range of phthalonitrile resin and can Used in high-tech fields such as microelectronics and aerospace.

Description

A kind of method for preparing branched type aryl-s-triazine structure phthalonitrile resin

technical field

The invention belongs to the field of preparation of novel high-temperature-resistant polymer materials, and relates to a novel high-temperature-resistant phthalonitrile resin containing a branched structure and a preparation method thereof.

Background technique

Branched aryl-s-triazine structure phthalonitrile resin is a kind of high-performance thermosetting resin, which has excellent thermal stability, thermal oxidation stability, moisture resistance, flame retardancy, chemical stability and mechanical properties. Aerospace, electronics, ships, machinery and other fields have a wide range of applications, and the application prospects are broad.

Branched aryl-s-triazine structure phthalonitrile resin is a high-temperature-resistant high-performance thermosetting resin polymerized from phthalonitrile structural units. The research pioneer of this resin is the U.S. Naval Research Laboratory, which has prepared a variety of phthalonitrile resins with typical structures during the long-term research process.

The following documents and patents have listed some of the phthalonitrile monomers prepared synthetically through research in recent years, with low melting points (Bulgakov, B.A.; Babkin, A.V.; Dzhevakov, P.B.; Bogolyubov, A.A.; Sulimov, A.V.; Kepman, A.V. ; Kolyagin, Y.G.; Guseva, D.V.; Rudyak, V.Y.; Chertovich, A.V.Low-meltingphthalonitrile thermosetting monomers with siloxane-and phosphatebridges.Eur.Polym.J.2016,84,205-217), containing triaryl structure (Sheng,H.; Zhao, F.; Yu, X.; Naito, K.; Qu, X.; Zhang, Q.Synthesis and thermal properties of high-temperaturephthalonitrile polymers based on 1,3,5-triazines.High Perform.Polym.2016, 28(5),600-609), low curing temperature structure (Sheng,L.P.; Yin,C.P.; Xiao,J.Y.A novelphthalonitrile monomer with low post cure temperature and short cure time.RSCAdv.2016,6(27),22204-22212 ) The above-mentioned studies mainly focus on the change of molecular structure to make it have good heat resistance, mechanical properties, etc.; some studies focus on the expansion of composite materials and optics (Derradji, M.; Feng, T.; Wang, H. .; Ramdani, N.; Zhang, T.; Wang, J.; Henniche, A.; Liu, W.-b. .Polym.J.2016,25(6),503-514.Pan,L.; Jia,K.;Shou,H.;Zhou,X.;Wang,P.;Liu,X.U nification of molecular NIR fluorescence and aggregation-induced blue emission via novel dendritic zinc phthalocyanines. Journal of Materials Science 2017, 52(6), 3402-3418).

Most of the above-mentioned phthalonitrile monomers have a benzene ring as the basic skeleton and a linear structure, and their polymers and composite materials exhibit excellent heat resistance and mechanical properties. In order to expand the diversity of its structure and to explore the new structure of high temperature resistant phthalonitrile, the present invention introduces a rigid triaryl structure and a branched structure into the main chain of the polymer to prepare a branched The new type of phthalonitrile resin can expand its scope of application and application prospects, and the heat resistance of the obtained new resin also has very high thermal stability.

Contents of the invention

Compared with the technical background, the present invention has the advantages of providing a novel preparation method of high-temperature-resistant phthalonitrile resin containing branched structure, which expands the application range of phthalonitrile resin and can be applied to Ships, aerospace and other high-tech fields.

A method for preparing branched aryl-s-triazine structure phthalonitrile resin, comprising the following steps:

Monomer synthesis: Add trifluoromethanesulfonic acid dropwise to chloroform at a temperature below zero, stir evenly, then add p-fluorobenzonitrile, and continue stirring; after reacting at room temperature for 6-48 hours, pour the product into 0.1-0.2 mol/L ammonia water to obtain a filter cake, then wash the filter cake with ethanol, and vacuum dry it at 80-120°C for 24-48 hours to obtain the monomer 2,4,6-3-(4-fluorophenyl) -1,3,5-triazine (TFPT), spare; wherein the molar ratio of p-fluorobenzonitrile: trifluoromethanesulfonic acid is 1:3, the volume of chloroform ml: the mass of p-fluorobenzonitrile g=20:1;

Synthesis of prepolymer: Mix TFPT, bisphenol, catalyst anhydrous potassium carbonate, solvent and water-carrying agent toluene in proportion, first carry water at 130-140°C for 2-3 hours, then at 140-180°C After the toluene is evaporated under the temperature condition, the reaction is continued for 8-12 hours under the temperature condition of 140-180°C; then the temperature is lowered to 80-90°C, 4-nitrophthalonitrile is added to the reaction solution, and additional Solvent, react for 10-12 hours; then pour the product into 0.1-0.2 mol/L hydrochloric acid, wash the filtrate with distilled water until it is neutral, and dry it in vacuum at 80-120°C for 24-48 hours to obtain branched o-phenyl Dicyanonitrile prepolymer, spare; wherein, the molar ratio of bisphenol: TFPT is 3-4.2, the molar ratio of bisphenol: anhydrous potassium carbonate is 1.2-1.6:1, and the solvent volume ml is 5-20 times that of bisphenol and The sum of the mass g of TFPT, the volume of toluene is 0.5-2 times the solvent volume, the amount of 4-nitrophthalonitrile added is used to consume the remaining bisphenol, and the volume ml of added solvent is 4-nitrophthalonitrile 3-5 times the mass g of diformonitrile;

Curing: Mix branched phthalonitrile prepolymer with aromatic diamine, fully mix and stir, compound with glass fiber to obtain a laminate, and place it in a muffle furnace at 250-375 ° C for 16 hours of temperature-programmed curing. Finally, a branched aryl-s-triazine structure phthalonitrile resin is obtained; wherein the branched phthalonitrile prepolymer:aromatic diamine mass ratio is 1:0.05.

Described bisphenol is biphenol, hydroquinone, pyrocatechol, resorcinol, bisphenol A, bisphenol AF, bisphenol fluorene, 4-(4-hydroxyl) phenyl-2, 3-Naphthyridine-1-one (DHPZ), 2,7-naphthalenediol, 1,5-naphthalenediol, 1,6-naphthalenediol, 2,6-naphthalenediol, 1,3- Naphthalenediol, 2,3-naphthalenediol or 1,8-naphthalenediol.

The solvent is N,N-methylformamide, N,N-methylacetamide, dimethylsulfoxide or N-methylpyrrolidone.

The aromatic diamine is 4,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 1,3-bis(4-aminobenzene oxy)benzene, 4,4'-bis(4-aminophenoxy)diphenylsulfone, 2,6-bis(4-aminophenoxy)benzonitrile or 2,4-bis[4-(4 -aminophenoxy)phenyl]-6-phenyl-1,3,5-triazine.

Beneficial effects of the present invention: the introduction of aryl-s-triazine combined with the branched structure obtains a novel branched phthalonitrile resin structure. As a rigid group, aryl-s-triazine is introduced into the main chain of phthalonitrile resin, which shows good heat resistance, and the effect of branched structure increases the cross-linking density, which makes the thermal performance of the resin Excellent, the thermal decomposition temperature (T _5% ) can reach up to 581°C, and the glass transition temperature ( _Tg ) can reach 480°C. As a new type of branched phthalonitrile, it expands the range of phthalonitrile resins. Wide range of applications, and can be used in high-tech fields such as ships and aerospace.

Description of drawings

Fig. 1 is the proton nuclear magnetic spectrum spectrogram of biphenol branched phthalonitrile (BP-CN).

Figure 2 is a comparison of the infrared spectra of biphenol branched phthalonitrile (BP-CN) and prepolymer (BP-OH)

detailed description

The specific implementation manners of the present invention will be further described below in conjunction with the accompanying drawings and technical solutions.

Example 1

Monomer synthesis: add 10.0 g (83.94 mmol) p-fluorobenzonitrile and 22.8 ml (251.82 mmol) catalyst trifluoromethanesulfonic acid into the reactor, and then add purified 200ml of chloroform; add chloroform and p-fluorobenzonitrile at -15°C in a constant temperature tank, stir for 30 minutes, then gradually add trifluoromethanesulfonic acid dropwise into the reactor using a constant pressure dropping funnel, and stir for 1 hour , and then react at room temperature for 24 hours; pour the product into 0.1 mol/L dilute ammonia water, then wash the filter cake with ethanol, and dry it in vacuum at 80°C for 24 hours to obtain the monomer 2,4,6-3-(4- Fluorophenyl)-1,3,5-triazine (TFPT), standby;

Synthesis of prepolymer: add 0.02 mole of TFPT and 0.06 mole of biphenyldiphenol, 0.072 mole of catalyst anhydrous potassium carbonate, then add 184.2ml of solvent NMP, add 368.4ml of toluene in solvent volume, and carry water at 130°C After 2 hours, distill toluene at 150°C, react for 8 hours; add 0.072 moles of 4-nitrophthalonitrile to block, 62.3ml solvent NMP; react at 80°C for 10-12 hours; then the product Pour into 300ml of 0.1 mol/L dilute hydrochloric acid, wash the filtrate to neutrality with distilled water, and then vacuum-dry at 80°C for 24 hours to obtain a branched phthalonitrile prepolymer for subsequent use;

Curing: Weigh 10 grams of the branched phthalonitrile prepolymer obtained above and mix it with 0.5 grams of aromatic diamine, fully mix and stir, compound with glass fiber to obtain a laminate, and put it in a muffle furnace at 250 ° C /3 hours, 325°C/3 hours, 350°C/2 hours, 375°C/8 hours programmed temperature rise curing, and finally a branched phthalonitrile resin was obtained.

Fig. 1 is the NMR spectrogram of biphenol branched phthalonitrile (BP-CN), as can be seen from the figure, the baseline of the spectrogram is flat, and the peak shape is clear, without miscellaneous peaks, illustrating The synthesized monomer has high purity. Through calculation, each hydrogen in the monomer structure is proved in the H NMR spectrum, which proves that the synthesized structure is biphenol branched phthalonitrile.

Fig. 2 is the infrared spectrogram contrast of biphenol branched phthalonitrile (BP-CN) and prepolymer (BP-OH), in the infrared spectrogram of BP-OH, 3417cm-1 place is The stretching vibration absorption peak of the hydroxyl group -OH is connected to the -OH of the water adsorbed on the surface of the sample here, so the absorption peak is relatively broad; 2231cm-1 is the stretching vibration absorption peak of -CN, and 1483cm-1 and 1360cm-1 are triazine rings The stretching vibration absorption peak. In the infrared curve of the product BP-CN, accompanied by the disappearance of -OH and the appearance of -CN at 2231cm-1, and the appearance of aromatic ether bond -C-O-C- at 1240cm-1, it is proved that branched phthalonitrile The structure of the resin:

The thermal decomposition temperature of the branched phthalonitrile prepared according to the method is as follows under air and nitrogen conditions:

(1) Air: T _id (initial thermal decomposition temperature) = 535°C, T _5% (thermal weight loss 5% temperature) = 568°C, carbon residue rate (800°C) = 36.2%;

(2) Nitrogen: T _id (initial thermal decomposition temperature) = 509°C, T _5% (thermal weight loss 5% temperature) = 573°C, carbon residue rate (800°C) = 79.1%, showing excellent heat resistance.

Example 2

The monomer synthesis steps are the same as in Example 1.

Prepolymer synthesis: add 0.02 moles of TFPT and 0.072 moles of biphenyldiphenol, 0.0864 moles of catalyst anhydrous potassium carbonate to the reactor, then add 206.5ml of solvent NMP, add 413ml of toluene as a solvent volume, and bring water to toluene at 130°C for 2 Hours, after distilling toluene at 150°C, react for 8 hours; add 0.1008 moles of 4-nitrophthalonitrile to block, 87.2ml solvent NMP; react at 80°C for 10-12 hours; then pour the product Put into 0.1 mol/L dilute hydrochloric acid of 300ml, after the filtrate is washed to neutrality with distilled water, 80 ℃ of vacuum dryings 24 hours, obtain the branched type phthalonitrile prepolymer, standby;

The curing steps are the same as in Example 1.

The thermal decomposition temperature of the branched phthalonitrile prepared according to the method is as follows under air and nitrogen conditions:

(1) Air: T _id (initial thermal decomposition temperature) = 517°C, T _5% (thermal weight loss 5% temperature) = 572°C, carbon residue rate (800°C) = 47.6%;

(2) Nitrogen: T _id (initial thermal decomposition temperature) = 504°C, T _5% (thermal weight loss 5% temperature) = 582°C, carbon residue rate (800°C) = 77.9%, showing excellent heat resistance.

Example 3

The monomer synthesis steps are the same as in Example 1.

Prepolymer synthesis: add 0.02 moles of TFPT and 0.06 moles of 4-(4-hydroxyl) phenyl-2,3-naphthyridine-1-one (DHPZ) to the reactor, 0.072 moles of catalyst anhydrous potassium carbonate, Then add 215.6ml solvent NMP, add 431ml solvent volume of toluene, carry water in toluene at 130°C for 2 hours, distill the toluene at 170°C, react for 8 hours; add 0.072 moles of 4-nitrophthalonitrile to block , 62.3ml solvent NMP; react at 80°C for 10-12 hours; then pour the product into 300ml of 0.1 mol/L dilute hydrochloric acid, wash the filtrate to neutral with distilled water, and dry it in vacuum at 80°C for 24 hours. Its structural formula is as follows:

The curing steps are the same as in Example 1.

The thermal decomposition temperature of the DHPZ type phthalonitrile prepared according to the method is as follows under air and nitrogen conditions:

(1) Air: T _id (initial thermal decomposition temperature) = 520°C, T _5% (thermal weight loss 5% temperature) = 573°C, carbon residue rate (800°C) = 48.6%;

(2) Nitrogen: T _id (initial thermal decomposition temperature) = 514°C, T _5% (thermal weight loss 5% temperature) = 586°C, carbon residue rate (800°C) = 78.9%, showing excellent heat resistance.

Example 4-13

The diphenol in the prepolymer synthesis step among the embodiment 1 is respectively made of hydroquinone, pyrocatechol, resorcinol, bisphenol A, bisphenol AF, bisphenol fluorene, 2,7-naphthalene Diphenol, 1,5-naphthalenediol, 1,6-naphthalenediol, 2,6-naphthalenediol, 1,3-naphthalenediol, 2,3-naphthalenediol or 1,8-naphthalenediol substitute , the structural formula of the branched phthalonitrile prepolymer obtained by it:

one of them are replaced by the following groups, respectively,

Other steps are the same as in Example 1, and the obtained product and physical property data are similar to Example 1.

Claims (4)

1. a kind of method for preparing branching type aryl s-triazine structure o-phthalonitrile resin, it is characterized in that comprising the following steps：

Monomer is synthesized：It is subzero in temperature, trifluoromethayl sulfonic acid is added dropwise into chloroform, after stirring, adds To fluorobenzonitrile, continue to stir；After reacting 6-48 hours at room temperature, in the ammoniacal liquor that product is poured into 0.1-0.2 moles/L, obtain Filter cake, then uses alcohol flushing filter cake, and 80-120 DEG C is dried in vacuo 24-48 hours, obtain monomer 2,4,6-3- (4- fluorophenyls)- 1,3,5-triazines, it is standby；Wherein, to fluorobenzonitrile：Trifluoromethayl sulfonic acid mol ratio is 1：3, chloroform volume ml：To fluorobenzonitrile quality G=20：1；

Prepolymer is synthesized：TFPT, bis-phenol, catalyst Anhydrous potassium carbonate, solvent and water entrainer toluene are mixed in proportion, existed first 130-140 DEG C of temperature conditionss Toluene band water 2-3 hours, after then steaming toluene under 140-180 DEG C of temperature conditionss, 140- Continue to react 8-12 hours under 180 DEG C of temperature conditionss；Then 80-90 DEG C is reduced the temperature to, 4- nitros are added into reaction solution adjacent Benzene dicarbonitrile, and solvent is added, react 10-12 hours；Then product is poured into 0.1-0.2 moles/L hydrochloric acid, with distillation Water washs filtrate to neutrality, and 80-120 DEG C is dried in vacuo 24-48 hours, obtains branching type phthalonitrile prepolymer, standby With；Wherein, bis-phenol：TFPT mol ratios are 3~4.2, bis-phenol：Anhydrous potassium carbonate mol ratio is 1.2~1.6：1, solvent volume Ml is 5~20 times of bis-phenols and TFPT mass g sums, and the volume of toluene is 0.5-2 times of solvent volume, 4- nitrophthalonitriles Addition is used to consume remaining bis-phenol, and the volume ml for adding solvent is 3-5 times of 4- nitrophthalonitrile quality g；

Solidification：Branching type phthalonitrile prepolymer is mixed with aromatic diamines, stirring is sufficiently mixed, is combined with glass fibre To laminate, and 250-375 DEG C of Muffle furnace Program elevated cure 16 hours is placed on, finally obtains branching type aryl s-triazine Structure o-phthalonitrile resin；Wherein branching type phthalonitrile prepolymer：Aromatic diamines mass ratio is 1：0.05.

2. the method according to claim 1 for preparing branching type aryl s-triazine structure o-phthalonitrile resin, its feature It is, described bis-phenol is '-biphenyl diphenol, hydroquinones, catechol, resorcinol, bisphenol-A, bisphenol AF, bisphenol fluorene, 4- (4- hydroxyls) phenyl -2,3- benzodiazine -1- ketone (DHPZ), 2,7- naphthalenediols, 1,5- naphthalenediols, 1,6- naphthalenediols, 2,6- naphthalenes Diphenol, 1,3- naphthalenediols, 2,3- naphthalenediols or 1,8 naphthalenediols.

3. the method as claimed in claim 1 for preparing branching type aryl s-triazine structure o-phthalonitrile resin, its feature exists In described solvent is N, N-METHYLFORMAMIDE, N, N- methylacetamides, dimethyl sulfoxide (DMSO) or 1-METHYLPYRROLIDONE.

4. the method according to claim 1 for preparing branching type aryl s-triazine structure o-phthalonitrile resin, its feature It is, described aromatic diamines are DDS, 4,4 '-diaminodiphenyl ether, 4,4 '-MDA, Double (4- amino-benzene oxygens) diphenyl sulphone (DPS)s of 1,3- bis- (4- phenalgins epoxide) benzene, 4,4'-, (4- amino-benzene oxygens) benzonitriles of 2,6- bis- or 2,4- bis- [4- (4- amino-benzene oxygens) phenyl] -6- phenyl -1,3,5-triazines.