JPH0458808B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a novel method for producing aromatic polybenzoxazole resin. Generally, aromatic polybenzoxazole resins are known to have excellent heat resistance, mechanical strength, and electrical properties. In general, the influence of molecular weight is important in determining the properties of polymer resins. If the degree of polymerization is low and the molecular weight is small, the viscosity and flexibility will be insufficient, making it difficult to process into membranes, fibers, and molded products. Moreover, even if processed, sufficient properties such as strength and heat resistance cannot be obtained. On the other hand, if the molecular weight is too high, the fluidity of the resin will be poor, which will cause problems during processing. [Prior Art] Polybenzoxazole resins are generally obtained by subjecting a polyamide resin obtained by the reaction of a diamine compound and a dicarboxylic acid dihalide to a cyclodehydration reaction, and the degree of polymerization thereof is controlled by the degree of polymerization of the polyamide resin. This degree of polymerization is based on the raw material diamine compound,
It is controlled by the amount of dicarboxylic acid dihalide charged. Using equimolar amounts of these reaction components,
High molecular weight aromatic polybenzoxazole resins can be controlled. However, such control of the molecular weight is possible only when the reactivity of the reaction component as a raw material is sufficiently high; if the reactivity is poor, only a reaction product with a low molecular weight can be obtained. Conventionally, it has been difficult to obtain a high molecular weight polymer of the aromatic polybenzoxole resin, which is the object of the present invention, due to the poor reactivity of the diamine compound, which is a reactive component thereof. The present inventors have made earnest efforts to obtain an aromatic polybenzoxazole resin that has a sufficiently high molecular weight and exhibits excellent properties, and as a result, the present invention has been accomplished. [Specific means for solving the problem] That is, the present invention provides the following: (In the formula, R is a divalent aromatic group, X is a divalent organic group, and n is an integer of 1 to 200.) In producing the aromatic polybenzoxazole resin represented by the general formula (In the formula, R ₁ is a monovalent organosilicon group, R ₂ is hydrogen or a monovalent organosilicon group, and X is a divalent organic group.) An aromatic diamine represented by the general formula (In the formula, R is a divalent aromatic group and Y is a halogen.) By reacting the aromatic dicarboxylic acid dihalide represented by the formula in an organic solvent, the general formula (In the formula, R is a divalent aromatic group, X is a divalent organic group, and n is an integer of 1 to 200.) This is a method for producing an aromatic polybenzoxazole resin, which is characterized by carrying out a dehydration cyclization reaction. The aromatic polyamide resin represented by the above general formula () is produced by a reaction between an aromatic diamine represented by the above general formula () and a dicarboxylic acid dihalide represented by the above general formula (). As the aromatic diamine represented by the general formula (), the divalent organic group represented by X in the formula includes a single crystal, an alkylene group, a halogenated alkylene group,
Examples include sulfone group, sulfide group, amino group, carbonyl group, ether group, etc., but more specific examples include bis(3-trimethylsilylamino-4-trimethylsiloxyphenyl)methane,
1-phenyl-1,1-bis(3-trimethylamino-4-trimethylsiloxyphenyl)ethane,
2.2-bis(3-trimethylamino-4-trimethylsiloxyphenyl)propane, 2.2-bis(3-trimethylsilylamino-4-trimethylsiloxyphenyl)hexafluoropropane, 1
-Phenyl-1.1-bis(3-trimethylsilylamino-4-trimethylsiloxyphenyl)trifluoroethane, 1-trifluoromethyl-1.1
-bis(3-trimethylsilylamino-4-trimethylsiloxy)ethane, [4.4'-bis(trimethylsilylamino)-3.3'-bis(trimethylsiloxy)]biphenyl, [3.3'-bis(trimethylsilylamino)-4.4'-bis (trimethylsiloxy)] biphenyl, bis(3-trimethylsilylamino-4-trimethylsiloxyphenyl)sulfone, bis(3-trimethylsilylamino-4-
trimethylsiloxyphenyl) sulfide, bis(3-trimethylsilylamino-4-trimethylsiloxyphenyl) ether, bis(3-trimethylsilylamino-4-trimethylsiloxyphenyl)ketone, bis(3-trimethylsilylamino-4-trimethylsiloxy) (phenyl)amine etc. are effective. Examples of the aromatic dicarboxylic acid dihalide represented by the general formula () include isophthalic acid dichloride, terephthalic acid dichloride, 4,4'-biphenyl dicarboxylic acid dichloride, biphenyl ether 4,4'-dicarboxylic acid dichloride, and benzophenone dichloride. Examples include 4,4'-dicarboxylic acid dichloride, benzosulfone-4,4'-dicarboxylic acid dichloride, isopropylidene biphenyl-4,4'-dicarboxylic acid dichloride, hexafluoroisopropylidene biphenyl-4,4'-dicarboxylic acid dichloride, etc. . These may be used alone or in combination of two or more. In this method, the molecular weight of the polybenzoxazole resin represented by the general formula () is the same as that of the diamine compound represented by the general formula ().
It is limited by the amount of the dicarboxylic acid dihalide represented by: If equimolar amounts of these reaction components are used, a high molecular weight aromatic polybenzoxazole resin can be produced. In the present invention, the reaction between the aromatic diamine compound represented by the general formula () and the dicarboxylic acid dihalide represented by the general formula () is carried out in an organic solvent under substantially anhydrous conditions from -10°C to 50°C. The reaction is carried out at reflux temperature for several minutes to several hours. As the organic solvent that can be used in this method, a wide variety of generally known non-aqueous organic solvents can be used. Specifically, amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and pyridine;
Sulfur-based solvents such as dimethyl sulfoxide and tetramethylsulfone, benzene-based solvents such as benzene, toluene, anisole, diphenyl ether, nitrobenzene, benzonitrile, cresol, and phenol, and halogenated hydrocarbons such as chloroform, trichloroethane, carbon tetrachloride, etc. Examples include hydrogen, but are not limited thereto. The polybenzoxazole resin represented by the general formula () is produced from the polyamide resin represented by the general formula () by heating at 100 to 500°C for several seconds to several tens of hours in the presence or absence of a dehydrating agent. It is done by In the presence of a dehydrating agent such as polyphosphoric acid, the reaction can be carried out at lower temperatures. The reaction temperature can also be lowered by heating under reduced pressure. This reaction is carried out by forming a polyamide resin represented by the general formula () into a membrane,
It is also possible to react after forming into a fiber. Hereinafter, the present invention will be explained in more detail with reference to Examples. Example 1 2,2-bis (3
-trimethylsilylamino-4-trimethylsiloxyphenyl)hexafluoropropane 1.638g
(2.5 mmol) and 5 ml of dimethylacetamide,
The mixture was stirred and dissolved under a nitrogen gas atmosphere. After freezing this solution in a dry ice-acetone bath, 0.508 g (2.5 ml) of isophthaloyl dichloride was added. After changing to an ice bath and stirring slowly for 5 hours, the solution was poured into water to obtain a polyamide resin precipitate. The inherent clay of the resulting resin was 0.64 {0.5 g/dL dimethylcetamide, 30°C). Infrared absorption spectrum and elemental analysis result formula It was confirmed that the structure was Infrared absorption spectrum 1600cm ^-1 (NH) 1650cm ^-1 (C=O) Elemental analysis C H N Calculated value (%) 55.66 2.84 5.64 Actual value (%) 55.44 2.68 5.88 Next, this polyamide resin was treated with N-methyl- 2
- It was dissolved in pyrrolidone and spread on a glass plate to form a film. This film was heat-treated at 280 to 300°C for 10 hours in a nitrogen gas atmosphere to obtain a transparent and strong film. infrared absorption spectrum,
As a result of elemental analysis, it was confirmed that it was a polybenzoxazole resin represented by the following formula. Infrared absorption spectre 1620 cm ^-1 (C=N) Elemental analysis C H N Calculated value (%) 60.01 2.19 6.08 Actual value (%) 59.94 2.03 6.17 Example 2 In the same manner as (Example-1), 2.2-bis( 3
-trimethylsilylamino-4-trimethylsiloxyphenyl)hexafluoropropane 1.38g
(2.5 mmol) and 0.508 g of terephthalic acid chloride
(2.5 mmol) was reacted to obtain a polyamide resin. The inherent clay of the resulting resin was 0.65 (0.5 g/dL dimethylacetamide, 30°C). The results of elemental analysis and infrared absorption spectrum analysis are shown in Table 1. (Hereinafter, the analysis results of the practical examples and comparative examples are shown in Table 1.) From these results, it was confirmed that the structure was as shown below. This polyamide resin was treated in the same manner as in Example 1 to obtain a transparent and strong film. This material was a polybenzoxazole resin represented by the following formula. Example 3 In the same manner as in (Example-1), 2,2-bis(3-trimethylsilylamino-4-trimethylsiloxyphenyl)hexafluoropropane
1.638g (2.2mmol) and isophthalic acid chloride
0.254g (1.25mmol) and terephthalic acid chloride
0.254g (1.25mmol) was reacted to obtain a polyamide resin. The intrinsic viscosity of the resulting resin was 0.86 (0.5 g/dL dimethylacetamide, 30°C). As a result of the analysis, the structure was as shown in the following formula. A transparent and strong film was obtained by processing in the same manner as this polyamide resin (Example 1). This material was a polybenzoxazole resin represented by the following formula. Example 4 In the same manner as in (Example-1), 2.2-bis(3
-trimethylsilylamino-4-methylsiloxyphenyl)hexafluoropropane 1.638 g (2.5
mmol) and 0.737 g (2.5 mmol) of biphenyl ether-4.4'-dicarboxylic acid dichloride to obtain a polyamide resin. The intrinsic viscosity of the resulting resin was 0.47 (0.5 g/dL dimethylatomamide, 30°C). As a result of the analysis, it was confirmed that the structure was as shown in the following formula. A transparent and strong film was obtained by processing in the same manner as this polyamide resin (Example 1). This material was a polybenzoxazole resin represented by the following formula. Example 5 2.2-bis(3
-trimethylsilylamino-4-trimethylsiloxyphenyl)hexafluoroperopane 1.638g
(2.5 mmol) and 0.633 g (2.5 mmol) of 2.6-saphthalene dicarboxylic acid dichloride were reacted to obtain a polyamide resin. The intrinsic viscosity of the resulting resin is 0.60 (0.5
g/dL dimethylacetamide, 30°C).
As a result of the analysis, it was confirmed that the structure was as shown in the following formula. This polyamide resin was treated in the same manner as in Example 1 to obtain a transparent and strong film. This material was a polybenzoxazole resin represented by the following formula. Example 6 In the same manner as (Example-1), 2.2-bis(3
-trimethylsilylamino-4-trimethylsiloxyphenyl)hexafluoropropane 1.638g
(2.2 mmol) and hexafluoroisopropylidene biphenyl-4.4'-dicarboxylic acid dichloride
1.073g (2.5mmol) was reacted to obtain a polyamide resin. The intrinsic viscosity of the produced resin is 0.40 (0.5g/dL
dimethylacetamide (30°C). As a result of the analysis, it was confirmed that the structure was as shown in the following formula. This polyamide resin was treated in the same manner as in Example 1 to obtain a transparent and strong film. This material was a polybenzoxazole resin represented by the following formula. Example 7 In the same manner as (Example-1), 2.2-bis(3
-trimethylsilylamino-4-trimethylsiloxyphenyl)propane 1.368 g (2.2 mmol),
0.508 g (2.5 mmol) of isophthalic acid chloride was reacted to obtain a polyamide resin. The intrinsic viscosity of the resulting resin is 0.55 (0.5 g/dL dimethylacetamide, 30
℃). As a result of the analysis, it was confirmed that the structure was as shown in the following formula. This polyamide resin was treated in the same manner as in Example 1 to obtain a transparent and strong film. This product was a polybenzoxazole resin represented by the following formula. Example 8 In the same manner as in Example 1, 1.262 g (2.5 mmol) of 4.4'-bis(trimethylsilylamino)-3.3'-bis(trimethylsiloxy)biphenyl and 0.508 g (2.5 mmol) of isophthalic acid chloride were reacted. A polyamide resin was obtained. The intrinsic viscosity of the resulting resin is 0.50 (0.5 g/dL dimethylacetamide, 30
℃). As a result of the analysis, it was confirmed that the structure was as shown in the following formula. This polyamide resin was treated in the same manner as in Example 1 to obtain a transparent and strong film. This material was a polybenzoxazole resin represented by the following formula. Comparative Example 1 Under the same conditions as (Example-1), 2.2-bis(3
0.915 g (2.5 mmol) of -amino-4-hydroxyphenyl)hexafluoropropane and 0.508 g (2.5 mmol) of isophthalic acid chloride were reacted to obtain a polyamide resin. The product is (Example-1)
It had the same structure as the polyamide resin manufactured by.
The intrinsic viscosity of the polyamide resin produced is 0.08 (0.5g/
dL dimethylacetamide, 30°C). This polyamide resin was treated in the same manner as in Example 1, but no film was obtained, and only powdered polybenzoxazole was obtained.

【table】

[Table] [Effects of the present invention] The present invention provides an advantageous method for producing an aromatic polybenzoxazole resin represented by the general formula (). This resin has good properties such as heat resistance, weather resistance, mechanical strength, and electrical properties, and is known to be an excellent industrial material. Conventionally, it has been difficult to produce high molecular weight resins. In contrast, the present invention provides an advantageous method for producing the resin with a sufficiently high molecular weight, and has high industrial value.

Claims (1)

[Claims] 1. General formula (In the formula, R is a divalent aromatic group, X is a divalent organic group, and n is an integer of 1 to 200.) In producing the aromatic polybenzoxazole resin represented by the general formula (In the formula, R ₁ is a monovalent organosilicon group, R ₂ is hydrogen or a monovalent organosilicon group, and X is a divalent organic group.) An aromatic diamine represented by the general formula (In the formula, R is a divalent aromatic group and Y is a halogen.) By reacting the aromatic dicarboxylic acid dihalide represented by the formula in an organic solvent, the general formula (In the formula, R is a divalent aromatic group, X is a divalent organic group, and n is an integer of 1 to 200.) A method for producing a polybenzoxazole resin, which comprises carrying out a dehydration cyclization reaction.