JPS63328A - Prepreg whose matrix is polyimide resin precursor composition - Google Patents

Abstract

PURPOSE:To prepare a prepreg having tack, being moldable in an autoclave and giving a tough composite molding, by impregnating a fibrous base material with a mixture of a partly esterified tetracarboxylic acid and a diamide. CONSTITUTION:The title prepreg can be obtd. by impregnating a fibrous base material (B) with a polyimide resin precursor compsn. (A) as a matrix. Compsn. (A) is a mixture of a reactant of an arom. tetracarboxylic dianhydride represented by formula I with a hydroxyl group-containing compd. represented by R-OH and a diamine represented by formula II in a molar ratio of the arom. tetracarboxylic dianhydride to the diamine of 1/0.8-1.2. In the above-described formulae, Ar is a tetravalent arom. group and two pairs of two valance among the four valances are in ortho or peri position with respect to each other; R is a 1-6C alkyl group, a 6-9C arom. group etc.; R' is a 6C or higher arom. group, a 2C or higher aliph. group, or a 6C or higher alicyclic group.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a prepreg using a novel polyimide resin precursor composition as a matrix resin. More specifically, it is a prepreg whose matrix is a polyimide resin precursor composition that can be molded using a general autoclave and exhibits toughness, which is a characteristic of thermoplastic matrix resins, after molding. It is.

<Prior Art> Prepregs made from thermoplastic resins and IJ lux resins have been well known. For example, those using polysulfone as a matrix resin (for example, JP-A-47
-10493 Publication, G, E.

Husman, Natl, SAMPE, Sy
mp, 24 21 ('79), etc.), ÷Qs o2
-Q-0-), whose matrix resin is polyether sulfone having the structure (for example, D, G, C
Hasin, et al.

Natl, SAMPE Technical Co.
nf, ヱ395 ('7g).

R, B, Rigby, Natl, SAMP
E, Symp, 27745 ('82), etc.)
, and ÷0−<ΣoQO−).

Those whose matrix resin is polyetheretherketone having the structure (for example, J, T.

Hartness, Natl, SAMPE,
Technical Conf.

14 26 ('82). R, B, Rigby,
Natl, SAMPE.

Symp, 27 745 ('82), etc.).

Also, prepregs using polyimide as a matrix resin have been well known.

These include those using linear polyimide as a matrix resin (e.g. R, S, f) Udinyak, Nat
l.

SAMP, Symp, 18 307 ('73
). H.H.Gibbs.

Natl, SAMP, Symp, 17 5
1-B-3ix0H, f(, Gibb
s, Natl, SAMPE, Symp,
20 212C75). H.H.Gibbs,
Natl, SAMPE, Te-chnica
l Conf, 10 211 ('78). H,
f(, Gibbs□.

Natl, SAMPE, Symp, 291
073 ('84), etc.), and those using crosslinked thermosetting polyimide as a matrix resin (for example, U.S. Pat. No. 4,166,170, U.S. Pat. No. 4,233,258, T, T, 5erafini et a
l,, NASA Technical Memo,
NASA TMX-71894 ('76). T
, T.

5erafini et al., J. App.
l, Polym, Sci,, 16905 ('
72). T, L, St, C1air et
al,, Natl.

SAMPE, Symp, 23 520 ('7
8). J.S.

Jones, Natl, SAMPE Tech
nical Conf, 14402(”82))
and so on.

<Problems to be solved by the invention> However, composite molded products obtained from prepregs using thermoplastic resins such as polysulfone, polyethersulfone, and polyetheretherketone as a matrix material have not been strong enough. Although it has excellent physical properties such as , prepreg has no tackiness at all and has the serious problem of being unable to be molded in an autoclave.

Composite molded products obtained from prepregs using linear polyimide as a matrix resin also have excellent physical properties such as heat resistance, but linear polyimide is a solid with a high melting point (softening point), so it cannot be melted. Impregnation is difficult, and prepregs using a linear polyimide matrix alone have no tack. Therefore, the solution of linear polyimide or its precursor polyamic acid 78
The base material is impregnated with a solution in the form of H, and in order to maintain tackiness, it is subjected to bond layer autoclave molding with some of the solvent remaining, while removing the solvent and performing the imide ring-closing reaction when polyamic acid is used. A method of molding is used. However, these linear polyimides and their precursor polyamic acids are N,N-dimethylformamide, N,N-dimethylacetamide and N
- Because only high-boiling polar solvents such as methylpyrrolidone are available, strict temperature/depressurization control is required to remove these solvents during molding. Moreover, these high boiling point polar solvents have a very high affinity for polyimide and its precursor polyamic acid, so it is very difficult to completely remove them after impregnating the base material, and some residual solvent may be the cause. The origin occurs when voids are generated in the cured product and the physical properties of the cured book are deteriorated.

In addition, since the preliminary resin of crosslinked thermosetting polyimide is a solid with a high melting point, it is used as a solution in a high-boiling polar solvent with high affinity when impregnating it into the substrate, so as mentioned above, Similar to linear polyimide: has an origin.

Therefore, as a method for solving the black point problem in crosslinked thermosetting polyimide resins, researchers at NASA have developed a method that utilizes a monomeric precursor composition of crosslinked thermosetting polyimide resins. For example, the 'L developed by NASA
ARC-160'' consists of a mixture of compounds A-C (section a, U.S. Pat. No. 4,166,170;
(U.S. Pat. No. 4,233,258, etc.).

A, Reaction product of benzophenonetetracarboxylic dianhydride and ethyl alcohol B, Reaction product of nadic acid anhydride and ethyl alcohol C, Polyamines H2NoC) i2ONH2 This 'LARC-160' is a very viscous one night product. It is possible to impregnate the base material without the aid of a solvent.It is also soluble in boiling point solvents such as alcohols, and can be diluted with these solvents to further impregnate the base material. cJ can be easily made.

The prepreg thus obtained also has task properties and can be molded in an autoclave. In this way, 'LARC-160', which uses a monomer precursor composition of cross-linked thermosetting polyimide resin, overcomes the process problems that conventional cross-linked thermosetting polyimide resins and precursors had. Although this problem has been improved, since it is a crosslinked thermosetting type, the final cured product has insufficient strength and is brittle, which is a serious drawback.

Therefore, in the present invention, the finally obtained composite molded product is a linear thermoplastic type matrix resin with high toughness, and when impregnated into a fiber base material, it has tackiness and can be molded in an autoclave. The objective is to obtain a prepreg that is capable of

Means for Solving the Problems In order to solve the above problems, the present inventors have made extensive studies and found that partial esters of tetracarboxylic acid and diamide/monomer, which are monomeric precursors of linear polyimide resins, have been developed. It was discovered that by using the mixture as a matrix resin, a new prepreg having the desired properties could be obtained, and the present invention was achieved.

That is, the present invention provides an aromatic tetracarboxylic dianhydride represented by the formula R-
It consists of a reaction product with a hydroxyl group-containing compound represented by 01() and a diamine represented by the formula H2N-R'-Nl2, and 0.8 to 1 of the above diamine per 1 mole of the above aromatic tetracarboxylic dianhydride.
．． A prepreg having a matrix of a polyimide resin precursor composition of 2 mol and a polyimide resin pre-J body composition consisting of @8M1 base material (here, Ar is a tetravalent aromatic group, and two of the The two sets of valences are in an ortho or peristaltic relationship with each other, and R is an alkyl group having 1 to 6 carbon atoms, an aromatic group having 6 to 9 carbon atoms, an alkoxyalkyne group having 2 to 10 carbon atoms, or Flucoxyalkyleneoxyalkylene J having 3 to 10 carbon atoms, R' represents an aromatic group having 6 or more carbon atoms, an aliphatic group having 2 or more carbon atoms, or an alicyclic group having 6 or more carbon atoms.) It is something.

The polyimide resin precursor composition, which is one of the constituent components of the present invention, is mainly composed of the above two components a and b.

Specific examples of aromatic tetracarboxylic dianhydrides and their pen/ze/nucleus substituted products are mentioned. These aromatic tetracarboxylic dianhydrides are used in one portion or in a mixture of 24 or more.

Formula R-O reacted with aromatic tetracarboxylic dianhydride
Specific examples of the hydroxyl group-containing compound represented by H include methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, pentyl alcohol, ethylene glycol monomethyl ether (methyl cellosolve),
Examples include ethylene glycol monoethyl ether (ethyl cellosolve), ethylene glycol monopropyl ether (propyl cellosolve), ethylene glycol monomethyl ether (butyl cellosolve), diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether. These water r group-containing compounds may be used alone or in a mixture of 21 or more.

The reaction conditions for the aromatic tetracarboxylic dianhydride and the hydroxyl group-containing compound in the polyimide resin precursor composition of the present invention are set such that the amount of the hydroxyl group-containing compound is less than 2 moles per 1 mole of the aromatic tetracarboxylic dianhydride. Although it is possible to allow some of the acid anhydride groups to remain, it is usually recommended that 2 moles or more of the hydroxyl group-containing compound be reacted.

In this case, component a is mainly composed of a partial ester represented by the following formula.

An isomer in which the bonding position l of HO2C- is switched.

(Here, Ar represents a tetravalent aromatic group, and the two groups of divalent groups among the tetravalents are in the ortho position or the position relationship with each other.) If an excess of the hydroxyl group-containing compound is used, the remaining Water 2 Fund H compounds remain. In practical applications, it is possible to remove the remaining components and use component a alone, or to leave it remaining and use it in a mixed state with component a. Usually, it is often preferable to use the compound with a slight excess of the hydroxyl group-containing compound remaining.

The reaction between the aromatic tetracarboxylic dianhydride and the hydroxyl group-containing compound is usually carried out at 0 to 200°C (more preferably at 20-1
50° C.) for 0.5 to 20 hours.

Although this reaction can be carried out in a solvent inert to the esterification of acid anhydrides, conduction is carried out without using any other special solvent since the hydroxyl group-containing compound is in a liquid state.

Specific examples of the diamine represented by the formula H, N-R'-NH of component b include meta-phenylene diamine, para-phenylene diamine, diaminodiphenyl ether, diaminodiphenylmethane, diaminodiphenylsulfone, diaminodiphenyl sulfide, diaminodiphenylethane, and diaminodiamine. diphenylpropane, diaminodiphenylketone, diaminodiphenylhexafluoropropane,
Bis(aminopheno-P7)benzene, bis(aminophenoxy)diphenylsulfone, bis(aminoenoxy)diphenylpropane, bis(aminophenyl)cyclohexane, diaminonaphthalene, o,o'-dimethylbenzidine, 0.0'-dimethoxybenzidine ,o,o
'-dichlorobenzidine, xylyle/diamine, 4.4
'-diaminodicyclohexylmethane, diaminocyclohexane, hexamethylenediamine, ethylenediamine, trimethylenediamine, tetramethylenediamine, undecamethylenediamine, alkyl having 1 to 3 carbon atoms, alkoxy having 1 to 3 carbon atoms, and halogen-substituted products thereof, etc. can be mentioned. These diamines are used in mixtures of 1 m or 24 or more.

The ratio of each of the above components in the polyimide resin precursor composition of the present invention is 0.8 to 12 moles (more preferably 0.8 to 12 moles) of diamine per 1 mole of aromatic tetracarboxylic dianhydride.
9 to L1 mol). Diamine is less than 0.8 mol or 12 mol per mol of aromatic tetracarboxylic dianhydride
Polyimide is finally obtained when you enjoy moles! This is not preferred because the degree of polymerization of the R fat does not increase and the strength is low and brittle.

Component a and b of the polyimide resin precursor composition of the present invention
Preferably, the components are mixed at a temperature below 120°C (more preferably 100°C).

In addition to component a and component b, a hydroxyl group-containing compound represented by the formula R-OH and its solvent can also be added to the polyimide resin precursor composition of the present invention for the purpose of adjusting the viscosity. .

As additional solvent, N, which is common as a solvent for imide resin,
Although it is possible to use aprotic polar solvents such as N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, and dimethylsulfoxide, they have low affinity for imide compounds and are easy to remove.
1 alcohols, 6m alkylene glycol monoalkyl ethers (cellosolve, etc.), volatile ketones,
Various halogenated hydrocarbons and the like are preferred.

Moreover, the polyimide precursor composition of the present invention can also be used in a blend with other thermoplastic polymers and/or thermosetting resins.

The fiber base material, which is the other component of the present invention, includes carbon fiber, glass fiber, boron fiber, silicon carbide fiber,
Examples include inorganic fibers such as asbestos 2 fibers, polyaramid 1 fibers, polybenzimidazole fibers, polybenzimidazole fibers, and polybenzithiazole W4 fibers. These fiber base materials are used in the form of LID, cloth, mat or cut fiber.

Polyimide front body material) IJ Nox is impregnated into the fiber base material by melt impregnation without using a solvent or by solution impregnation using the above-mentioned solvents.Then, if necessary, the solvent is removed to obtain a prepreg. It will be done.

The prepreg of the present invention obtained in this way has characteristics such as tankability and drapability, and
1 Press molding is of course possible, but autoclave molding is also possible. The prepreg of the present invention undergoes a polymerization reaction during molding, and ultimately becomes a composite molded product having a linear polyimide tree B2 having strong A properties and excellent heat resistance as a matrix.

<Example> The present invention will be explained in more detail below with reference to Examples.

Note that the values of %, parts, and ratios used in this example are
Unless otherwise specified, the values for weight %, covering area and weight ratio are shown, respectively.

Measurement of each sample was carried out according to the following method.

Bending stress: ASTM D790 bending modulus ・
... ASTM D648-56 (18,56
kg/cG Example 1 Benzophenonetetracarboxylic acid dihydrate 483.3 in a four-bottle flask with an internal volume of 311 equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen inlet tube under a nitrogen atmosphere.
f (1,5 mol) and ethylene glycol monomethyl ether (methyl cellosolve) 570.7 f
(7.5 mol) was charged and reacted at 110°C for 2 hours to obtain a homogeneous solution.

The reaction mixture was then cooled to 60°C and 2.2-(4°4'
-His(p-aminophenoxy)diphenyl]propane (hereinafter abbreviated as PODA) 615.81 (15 mol) was added little by little and mixed by 8 folds to obtain a viscous polyimide resin precursor composition.

Next, the obtained composition was melted and impregnated into a carbon fiber cloth base material (Toyoshi Trading Card Cloth #6142) at 80° C. to obtain a prepreg. The obtained Gripreg had prepreg properties such as drapability and tackiness.

Next, the obtained Gripreg was cut into 25L11×15Y1 pieces, and then 16 pieces were layered. Place the bonded prepreg in a vacuum bag, sandwich it between stainless steel plates, set it in an autoclave, and heat it at 100°C for 1 hour.
Apply a pressure of kq/c4 and heat at 120°C for 1 hour, then 1
Molding was performed under temperature conditions of 50° C. for 1 hour and 290° C. for 1 hour to obtain a composite molded plate.

When the physical properties of the obtained composite plate were measured, the results shown in Table 1 below were obtained.

Table 1 Example 2 Using absolute ethanol 4611 (10 mol) instead of ethylene glycol 7-methyl ether (Methyl Cellsolve) 570.7 F (7.5 mol) and PODA 615.8N O, 5 mol ) instead of 3,4'-diaminodiphenyl ether 300.3y
Same as Example 1 except for using (1.5 mol)? When this synthesis operation was performed, a viscous polyimide resin precursor composition was obtained.

The composition obtained next is 200! diluted with 100f of ethanol, and prepared with carbon fiber cloth base material (Torayka Cross #
6142) and then heated at 70℃ for 30 minutes.
After drying at 0° C. for 15 minutes, a prepreg with $2% of ethanol remaining in the matrix was obtained. The obtained prepreg had properties such as drapeability and tackiness that enabled it to be molded in an autoclave.

Next, the obtained prepreg was cut into a size of 25 a x 15 m, 16 sheets were laminated, and autoclave molded in the same manner as in Example 1 to obtain a composite molded plate.

When the physical properties of the obtained composite molded plate were measured,
The results shown in Table 2 below were obtained.

Table 2 Comparative Example 1 The reactor of Example 1 was charged with 100.1 F (0.5 mol) of 3,4'-diaminodiphenyl needle and 2000, y of N-methylpyrrolidone under a nitrogen atmosphere. I made 8 folds. Next, while cooling the reactor in an ice water bath, benzophenonetetracarboxylic dianhydride 16
11 F (0.5 mol) was gradually added at a rate that did not allow the internal temperature to rise above 20°C. After the addition was completed, the reaction was further carried out for 1 hour at an internal temperature of 30°C, and a polyamic acid solution was obtained.

Next, the obtained polyamic acid solution was applied to a carbon 1 cloth base material (
After impregnating with Toshi trading card cloth #6142), 100 ~
Same as Example 2 at 200°C? When dried until the residual solvent in Trix was 2% by weight, the resulting prepreg had no tackiness or drapeability at all, and could not be molded in an autoclave. In order to maintain tackiness and drapeability in this polyamic acid prepreg, 3% N-methylpyrrolidone is added to the matrix.
It was necessary to allow 0% by weight or more to remain.

Next, a prepreg in which 30% by weight of N-methylpyrrolidone remained in the matrix was prepared, and 2511X15c
After cutting to a size of 1.5 mm, 6 sheets of I were laminated in one layer and autoclaved in the same manner as in Example 2. The resulting composite molded product foamed and was of no practical use.Furthermore, The molding process was repeated by changing the molded article as shown in Table 3, but in each case the molded products obtained had a large number of voids and were of no practical use.

Table 3 Example 3 Benzophenone tetracarboxylic dianhydride 483.3
using biphenyltetracarboxylic dianhydride 441°3F (1,5 mol) instead of y (1,5 mol) and PODA 615. +H+ (h5 mol), this 4,4'-diaminodiphenylmethane 297.
Same as Example 1 except that 4F (15 mol) was used)
When the synthesis operation was performed, a viscous polyimide resin precursor composition was obtained.

Next, the obtained composition was impregnated into a carbon fiber cloth base material (Torayka Cloth J 6142) at 80° C. to obtain a prepreg. The obtained prepreg had properties such as drapeability and tackiness that enabled it to be molded in an autoclave.

<Effects of the Invention> The Gripreg of the present invention has special features such as tackiness and drapability required for autoclave molding, and can be press-molded as well as autoclave-molded.

The composite molded body laminated with the prepreg of the present invention and molded into 11 parts has excellent mechanical properties such as toughness and heatability, and is used in various applications such as electronic parts, anti-aircraft/Uichi d equipment parts, automobile parts, etc. Widely used in fields such as equipment parts.

Claims (1)

[Claims] (A) a, an aromatic tetracarboxylic dianhydride represented by the formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼ and the formula R-
Consisting of a reaction product with a hydroxyl group-containing compound represented by OH and b, a diamine represented by the formula H_2N-R'-NH_2, 0.8 to 1 of the above diamine per 1 mole of the above aromatic tetracarboxylic dianhydride.
．． A prepreg having as a matrix a polyimide resin precursor composition consisting of a 2 mol polyimide resin precursor composition and (B) a fiber base material. (However, here, Ar is a tetravalent aromatic group, and two sets of divalents among the tetravalents are in the ortho or peri position relationship with each other, R is an alkyl group having 1 to 6 carbon atoms, and An aromatic group having 6 to 9 carbon atoms, an alkoxyalkylene group having 2 to 10 carbon atoms, or an alkoxyalkyleneoxyalkylene group having 3 to 10 carbon atoms, R' is an aromatic group having 6 or more carbon atoms, an aliphatic group having 2 or more carbon atoms group, alicyclic group having 6 or more carbon atoms.)