JPH0460489B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a bisphthalonitrile compound that forms a three-dimensional network structure. More specifically, due to the reactivity of bisphthalonitrile compounds,
The present invention relates to a thermosetting resin raw material composition that increases crosslinking density and, as a result, provides a cured product having a high modulus of elasticity and good heat resistance. [Prior Art] It has been reported that a three-dimensional network structure is formed in certain bisphthalonitrile compounds by heating and melting them or by heating and melting them with a curing agent and causing condensation polymerization (Journal of Applied Polymer
Science, Vol 293339 (1984)). In addition, attempts have been made to develop polymeric materials with high elastic modulus by solid-phase polymerization of diacetylene compounds (for example, Journal of Polymer Science, vol.
B9133 (1971), Journal of Polymer Science,
Polymer−Physics Edition Vol 121511
(1974)). [Problems to be Solved by the Invention] Bisphthalonitrile and diacetylene compounds can form a three-dimensional network structure by utilizing the high reactivity of cyano groups and acetylene groups. However, the results of previous research have shown that the crosslinking density of the curing agent has not been sufficiently increased, and the elastic modulus has been too high.
The pressure was insufficient at around 10 GPa. [Means for Solving the Problems] Therefore, the present inventors have conducted intensive research into further increasing the modulus of elasticity and improving the heat resistance of a molded article using a condensate of bisphthalonitrile. That is, the present invention includes the following components (A), (B), and (C), and contains 100% of the component (B).
Component (A) is blended in a ratio of 1 to 50 parts by weight to parts by weight, and component (C) is blended in a ratio of 1 to 10 parts by weight to 100 parts by weight of components (A) + (B). The present invention relates to a characteristic thermosetting resin raw material composition. (A) Component: Tetracyanobenzene (B) Component: Bisphthalonitrile represented by the following formula (In the formula, R represents an aromatic hydrocarbon ring.) (C) Component: Curing agent R of the component (B) in the present invention represents an aromatic hydrocarbon ring, and the bond in the main axis direction is a nonlocalized one of at least π electrons. It is characterized by the fact that the strength of the bond becomes stronger than that of a single σ bond. As a specific example of R,

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Examples include, but are not limited to, [Formula]. As the curing agent for component (C) in the present invention, amine compounds are usually suitable. For example, m-phenylenediamine, p-phenylenediamine, 4,4'-methylenedianiline, 4
-aminophenyl ether, 4,4'(p-phenylenedioxy)dianiline, 4-aminophenyl sulfone, and the like. These may be used alone or in combination of two or more. In the composition of the present invention, the amount of component (A) to be blended relative to 100 parts by weight of component (B) depends on the chemical structure of component (B), but is preferably 1 to 50 parts by weight, more preferably 2 to 30 parts by weight. Weight parts are good. (B) The amount of component is 1
If it is less than part by weight, the crosslinking density of the composition will be difficult to increase, and the strength and elastic modulus of the cured product after thermal crosslinking will be low, which is not preferable. On the other hand, if the amount of component (B) exceeds 50 parts by weight, the crosslinking density increases to some extent, but on the other hand, the cured product loses its flexibility and becomes extremely brittle, which is not preferred in practice. Furthermore, in the composition of the present invention, (A) + (B) components
The curing agent (C) component is added in an amount of 1 to 10 parts by weight per 100 parts by weight. When the amount of component (C) is less than 1 part by weight, there are disadvantages such as slow curing speed.
Practically unfavorable. Furthermore, if the amount of component (C) exceeds 10 parts by weight, the curing speed increases, but the substantial crosslinking density decreases, making it impossible to obtain desirable mechanical properties. The following components can be added to the composition of the present invention as necessary. (1) Powdered reinforcing agents and fillers, such as metal oxides such as aluminum oxide and magnesium oxide, metal hydroxides such as aluminum hydroxide,
Metal carbonates such as calcium carbonate and magnesium carbonate, diatomaceous earth powder, basic magnesium silicate, calcined clay, fine powder silica, fused silica,
Crystalline silica, carbon black, kaolin, finely powdered mica, quartz powder, metal hydroxides such as aluminum hydroxide, graphite, asbestos, molybdenum disulfide, antimony trioxide, etc. In addition, fibrous reinforcements and fillers, such as glass fibers, rock wool, ceramic fibers,
These include asbestos, inorganic fibers such as carbon fiber, and synthetic fibers such as paper, pulp, wood flour, linters, and polyamide fibers. The amount of these powder or fibrous reinforcing materials or fillers used varies depending on the purpose, but as a laminated material or molding material, up to 500 parts by weight can be used per 100 parts by weight of the resin composition. (2) Colorants, pigments, flame retardants such as titanium dioxide, yellow carbon black, iron black, molybdenum red, navy blue, ultramarine blue, cadmium yellow, cadmium red, inorganic phosphorus such as red phosphorus, and organic such as triphenyl phosphate. Such as phosphorus. (3) Furthermore, various synthetic resins can be blended for the purpose of improving the properties of the resin in the final coating film, adhesive layer, resin molded product, etc. For example, phenolic resin, alkyd resin, melamine resin, fluororesin, vinyl chloride resin, acrylic resin, silicone resin, polyester resin, etc.
Species or combinations of two or more types can be mentioned. The amount of these resins used is preferably within a range that does not impair the inherent properties of the resin composition of the present invention, that is, less than 50% by weight of the total resin amount. Examples of blending methods for component (A), component (B), component (C), and various additives include heating and melt mixing, kneading using a roll, kneader, etc., and mixing using an appropriate organic solvent. . -Synthesis of component A- 1,2,4,5-tetracyanobenzene is usually synthesized by a method using pyrometh acid tetraamide as an intermediate. This intermediate can be prepared by heating the ammonium salt of pyromellitic acid to form pyromellitic acid diimide, which is then treated with aqueous ammonia (Monatsh. 35, 396 (1914)). In addition, the reaction of reacting pyromellitic anhydride and urea in monochlorobenzene to obtain pyromellitic acid tetraamide in one step
khim Reaktivovi Preparatov No.12, 108
(1965)). To synthesize 1,2,4,5-tetracyanobenzene from the intermediate pyromellitic acid tetraamide thus obtained, a method of dehydration with thionyl chloride using dimethylformamide as a solvent is used (Chemistry and Industry, 1964, 752). -Synthesis of component B- The synthesis method for component B is the reaction of 4-nitrophthalonitrile with an alkali salt of biphenol (“Resins for
Aerospace”, Am.Chem.Soc.Symp.Ser., 132,
25 (1980)), various bisphthalonitriles are obtained. [Methods for measuring properties and evaluating effects] (1) Flexural modulus The standard method for measuring the flexural modulus is
ASTM-D790-66 can be used. However, the molded product of the present invention may not necessarily be large enough to be measured by the ASTM measurement method. Therefore, the following method was used to measure the flexural modulus of the small molded product. That is, to measure the flexural modulus mentioned above, the test piece is 30 mm long, 5 mm wide, and 1 mm high.
Measurements were made with the following settings: distance between fulcrums 16 mm, fulcrum tip radius 2R, pressure wedge tip radius 5R, and test speed 0.5 mm/min. In this case, although the flexural modulus was measured slightly smaller than the ASTM method, almost similar values were obtained. (2) Electrical conductivity Plate specimen (thickness 1mm, width 5mm, length 30mm)
A conductive paint (“Dotite”, manufactured by Fujikura Kasei Silver Co., Ltd.) was applied to both ends of the film, and after drying, the resistance value was measured using a digital multi-thermometer (manufactured by Takeda Riken Kogyo Co., Ltd.). The electrical conductivity was determined from this resistance value according to a conventional method. (3) Impact resistance The impact resistance of the sample was measured using a Shalpy impact tester (Co., Ltd.).
(manufactured by Toyo Seiki Seisakusho), and the impact value was evaluated as the value obtained by dividing the energy required to break by hitting it with a hammer by the cross-sectional area of the sample. In the test, a plate-like object with a cross-sectional area of 5 mm ² (1 mm x 5 mm) and a length of 40 mm was struck perpendicular to its length to break it. The distance between the fulcrums was chosen to be 20 mm. Hammer weight (1Kg) speed, cutting edge radius, and support trapezoid shape were in accordance with JIS standards. Those with an impact value of 4 kg·cm/cm ² or less were judged to have poor impact resistance, and those with an impact value of 4 kg·cm/cm ² or more were judged to be good. [Effects of the Invention] The composition of the present invention is composed of two types of bisphthalonitrile compounds with different properties, and the cyano groups are intermolecularly cross-linked by heat treatment for forming, resulting in a high-performance composition with excellent impact resistance and thermal properties. A rigid molded body can be obtained. Furthermore, since this crosslinked body is composed of π-electron conjugated bonds, it exhibits excellent electrical conductivity. Therefore, the composition of the present invention can be used in a wide range of fields such as electronic materials, aerospace, precision machinery, and structural materials. [Examples] A more specific explanation will be given below with reference to Examples, but these Examples are merely illustrative, and the present invention is not limited by the Examples. Example 1 109 parts by weight of pyromellitic anhydride, 100 parts by weight of urea, and about 700 parts by weight of monochlorobenzene were charged into a reaction vessel equipped with a stirring blade, a condenser, and a thermometer. Under reflux for 7.5 hours with stirring (118~
125°C). After cooling, it is filtered through a glass filter, and the resulting slightly yellow powder is air-dried.
350 parts by weight of concentrated aqueous ammonia was added to the air-dried powder, stirred for 1.5 hours, and then filtered. The obtained powder was further extracted twice with 350 parts by weight of concentrated aqueous ammonia to remove unreacted substances. After extraction with aqueous ammonia, wash with water until the filtrate becomes neutral. Further vacuum drying yielded 107 parts by weight of pale pink pyromellitic acid tetraamide. Pyromellitic acid tetraamide obtained here
37.5 parts by weight was placed in a container, and 250 parts by weight of dehydrated dimethylformamide was added. While keeping the reaction solution in the container at -1 to -2℃ using an ice bath, add the mixture under stirring.
178 parts by weight of thionyl chloride was added dropwise over 2.5 hours. After completion of the dropwise addition, the reaction was allowed to proceed at room temperature for 2 days. After the reaction was completed, the orange transparent solution obtained by filtration through a glass filter was poured into a mixture of 200 parts by weight of ice and 100 parts by weight of concentrated hydrochloric acid. The precipitated crystals were filtered out using a glass filter, washed with water until the filtrate became neutral, and then dried. 18 parts by weight of 1, 2, 4, 5
-Tetracyanobenzene was obtained as a pale yellow powder. 24 parts by weight of the 1,2,4,5-tetracyanobenzene thus obtained was recrystallized using 390 parts by weight of acetic acid. 19 parts by weight of needle-like crystals were obtained.
This crystal was recrystallized using 110 parts by weight of methyl cellosolve. 13 parts by weight of almost white plate-like crystals were obtained. The melting point was 272-273°C. Next, 4,4'-bis(4-phenyleneoxyphthalonitrile) was synthesized by the following method. Put 110 parts by weight of concentrated ammonia water into a reaction container,
To this was added portionwise 25 parts by weight of 4-nitrophthalimide. After the addition, the reaction solution was stirred for 1 hour and then filtered through a glass filter. The obtained green-green powder was placed in a container, and 110 parts by weight of concentrated aqueous ammonia was added while stirring the liquid with a stirring blade. After stirring the suspension for 1 hour, the crystals were filtered out using a glass filter. The obtained crystals were washed with water until the filtrate became neutral, and then dried under vacuum. 23 parts by weight 4
-Nitrophthalamide was obtained. Next, 21 parts by weight of 4-nitrophthalamide and 88 parts by weight of dimethylformamide were charged into a reaction vessel, the liquid temperature was maintained at -29 to -34°C while stirring, and 62 parts by weight of thionyl chloride was added over 1 hour. dripped. After dropping, the temperature of the solution was slowly returned to room temperature over 4 hours.
The resulting green-brown clear solution was allowed to stand overnight and then poured into a mixture of 50 parts by weight of concentrated hydrochloric acid and 100 parts by weight of broken ice. Since crystals slowly precipitated, the mixture was kept at 10°C or lower for 2 hours with occasional stirring, and then filtered. The obtained cake was washed while the filtrate remained neutral, and when dried in vacuum, about 11 parts by weight of 4
- Nitrophthalnitrile was obtained as a gray-green powder. The melting point was 140-144°C. Next, 52 parts by weight of dimethyl sulfoxide, 59 parts by weight of P,P'-biphenol, 16 parts by weight of potassium carbonate, and 11 parts by weight of 4-nitrophthalnitrile were placed in a reaction vessel purged with nitrogen. The temperature of the mixed solution was raised from room temperature while stirring, and the temperature was kept at 56-59°C for 4 hours to react. After the reaction, the resulting reddish-brown dispersion was returned to room temperature and cooled with 125 parts by weight of 3NHCl.
I poured it little by little. Foaming occurred, but when this stopped and the temperature reached 7°C, the precipitated crystals were filtered out.
The filtrate was washed with water until it became neutral and dried under vacuum to obtain 13.3 parts by weight of 4,4'-bis(4-phenyleneoxyphthalonitrile) as a pale yellow powder. The melting point was 235-238°C. A polyphthalonitrile molded article was produced by condensation polymerization from 1,2,4,5-tetracyanobenzene and 4,4'-bis(4-phenyleneoxyphthalonitrile) synthesized as described above by the following method. Ivy. 97 parts by weight of 4,4'-bis(4-phenyleneoxyphthalonitrile), 3 parts by weight of 1,2,4,5-tetracyanobenzene, and 3 parts by weight of P-phenylenediamine were placed in a reaction vessel and thoroughly blended. After that, heat and melt at 250℃. After stirring for about 5 minutes after melting, the melt becomes slightly sticky, so heating is stopped and the mixture is cooled. Crush this into powder. Powdered prepolymer is put into a mold,
Using a compression press, mold into a plate (1 mm thick, 50 mm wide, 80 mm long) at 200°C and a pressure of 15 kg/cm ² . The obtained molded product was heat treated in a nitrogen atmosphere from 250 to 900°C in 50°C steps for 30 minutes at each temperature.
If the sample is suddenly treated at a high temperature, foaming or the like may occur, so it is preferable to gradually increase the treatment temperature in this way. The molded article obtained had a flexural modulus of 25 GPa, an electrical conductivity of 2.1×10 ² S/cm, and good impact resistance. Example 2 and Comparative Examples 1 and 2 Polyphthalonitrile molded products were produced by changing the blending ratio of tetracyanobenzene and bisphthalonitrile and the amount of curing agent added under the conditions of Example 1. Ivy. Table 1 shows the properties of these molded products.
These results show that molded bodies obtained from compositions within the scope of the present invention are excellent in elastic modulus, electrical conductivity, and impact resistance. Comparative Example 3 After purging a reaction vessel with a stirring blade with nitrogen, 38.4 parts by weight of dimethyl sulfoxide, 5.3 parts by weight of bisphenol A, 11.7 parts by weight of potassium carbonate, and 8.1 parts by weight of purified 4-nitotophthalonitrile were added in order. The temperature was raised while stirring while nitrogen was gradually introduced. Fever is seen around 45℃. The reddish-brown dispersion obtained after reacting at 56-62°C for 4 hours was poured into 95 parts by weight of cooled 3NHCl. After cooling to 10°C, the precipitated crystals were filtered out, washed with water until the filtrate became neutral, and then dried in vacuum. 10.7 parts by weight of 4,4'-isopropylidene-bis(4-phenyleneoxyphthalonitrile) was obtained as a pale yellow powder. 4,4′-isopropylidene-bis(4-phenyleneoxyphthalonitrile) thus obtained
To 90 parts by weight, 10 parts by weight of tetracyanobenzene and 3 parts by weight of P-phenylenediamine are placed in a reaction vessel and heated and melted at 250°C. After stirring for 5 minutes,
The mixture was placed in a mold for molding, and a molded product was obtained by the method described in Example 1 below. This molded product had a low flexural modulus of 3 GPa, poor impact resistance, and did not exhibit desirable properties. Example 3 Using 1,4-bis(3',4'-dicyanophenoxy)benzene obtained in the same manner as in Example 1 except that an equivalent amount of hydroquinone was used instead of P,P'-biphenol. The flexural modulus of the obtained polyphthalonitrile molded body was 19GPa, and the electrical conductivity was 4.8×
10 ^-1 S/cm, the impact resistance was good.

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Claims (1)

[Scope of Claims] 1 Contains the following components (A), (B) and (C), and component (B)
Component (A) is 1 to 50 parts by weight per 100 parts by weight, (A)+
A thermosetting resin raw material composition characterized in that component (C) is blended in a ratio of 1 to 10 parts by weight to 100 parts by weight of component (B). (A) Component: Tetracyanobenzene (B) Component: Bisphthalonitrile represented by the following formula (In the formula, R represents an aromatic hydrocarbon ring) (C) Component: Curing agent