JPH04366131A - Thermosetting oligomer and its production - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

FIELD OF THE INVENTION This invention relates to a novel thermosetting oligomer. More specifically, the present invention relates to a polyimide that has excellent heat resistance, good solubility in organic solvents, and optimal reactivity for lamination and molding.

0002

[Prior Art and Problems to be Solved] Thermosetting resins are used as casting, impregnating, laminating, and molding materials for various electrical insulation materials, structural materials, and the like. In recent years, the conditions for using materials in each of these applications have become increasingly strict, and in particular, the heat resistance of materials has become an important characteristic. Conventionally, thermosetting polyimide resins and heat-resistant epoxy resins have been used for applications requiring heat resistance. Among them, the thermosetting polyimide resin used is kelimide, which is mainly composed of a combination of bismaleimide compounds and diaminodiphenylmethane [Matsuo Fujisawa, Plastics, 3rd Edition]
Volume 4, No. 7, Page 75, 1983]. However, polyimide has the disadvantage that it requires a high temperature and long heating process during its processing. In addition, acetylene-terminated polyimide is commercially available as Thermid [
Gulf R&D, JP-A-53-119865, etc.]. However, due to its relatively low solubility in organic solvents,
To make prepregs, dimethylformamide,
The resin must be dissolved using a high-boiling organic polar solvent such as dimethylacetamide, which poses problems in its handling. Many resin improvement methods have been proposed to solve these problems with polyimide, and among these, various polyesterimide resins have been proposed from the viewpoint of processing properties [for example, US Pat. No. 3,182,073] ,
No. 4,757,118, No. 4,362,861, 3
, No. 852, 246, etc. or JP-A-1-12381.
9, JP 1-163214, JP 2-138341
etc〕. However, although polyesterimide generally has a lower thermal softening point and better resin flow characteristics than polyimide,
It has been pointed out that it is inferior to polyimide in terms of heat resistance [
Keisuke Kurita et al., Polymer Processing, Volume 37, No. 2, 22-2
6 pages (1989)].

[0003] In addition, a similar method for synthesizing polyesterimide uses trimellitic anhydride as a starting monomer and a chlorinated p-toluenesulfonic acid/pyridine reaction solvent to synthesize a new acid dianhydride having an ester bond in the same system. A method of synthesis is also known, in which a diamine or the like is introduced after synthesis in H. Tanaka
et al. , Proceedings/Abst.
racts of Third International
nal Conference on Polyimi
des. 65-68 pp (1988)]. However, these findings are based on polymer films, and no knowledge has been reported regarding thermosetting or photoreactive ester imide oligomers that can be applied as matrix resins for laminated materials.

0004

[Means for Solving the Problems] In view of the above-mentioned circumstances, the present inventor has made extensive studies to solve these technical problems, and as a result, has arrived at the present invention. That is, the first aspect of the present invention is general formula (1)

[0005]

[Chemical formula 10]

(wherein R1 and R3 are divalent organic groups,
R2 is a tetravalent organic group, R4 is an organic group having thermal crosslinking reactivity, and R1 and R3 may be the same or different. X is 1 to 30, Y
represents a positive integer from 0 to 30. ) The new thermosetting oligomer shown in

The second aspect of the present invention is to maintain the reaction system at room temperature or lower in an inert gas atmosphere, and add an ester group-containing acid dianhydride represented by the following general formula (2) to an aprotic polar solvent, or Ester group-containing acid dianhydride and organic tetracarboxylic dianhydride represented by general formula (3)

[0008]

[Chemical formula 11]

(In the formula, R1 is a divalent organic group)

001
0]

[Chemical formula 12]

(wherein R2 is a tetravalent organic group) is dissolved in an aprotic polar solvent, and a diamine represented by the following general formula (4) is dissolved in an aprotic polar solvent.

0012

[Chemical formula 13]H2N-R3-NH2
(4)

(In the formula, R3 is a divalent organic group)
is added and reacted in an amount necessary to obtain a telechelic oligoester amic acid terminated at both ends, and an acid anhydride represented by the general formula (5) dissolved in an aprotic polar solvent is further added.

[0014]

[Chemical formula 14]

(wherein R4 is an organic group having thermal crosslinking reactivity) is added to terminate the terminal, and then a non-solvent is added to thermally ring-close and dehydrate under azeotropy. Each content includes a method for producing a curable oligomer.

The method for producing the novel thermosetting oligomer of the present invention will be explained. Dry the reaction tank thoroughly and fill it with argon.
An ester group-containing organic tetracarboxylic dianhydride represented by general formula (2) in an inert gas atmosphere such as nitrogen;

0
017]

[Chemical formula 15]

(wherein R1 is a divalent organic group) or the ester group-containing tetracarboxylic dianhydride and the general formula (3)
An organic tetracarboxylic dianhydride represented by;

0019
]

[Chemical formula 16]

(wherein R2 is a tetravalent organic group) is dissolved in a polar organic solvent, and in the solution is added an organic diamine compound represented by the general formula (4);

[0021]

[Chemical formula 17] H2N-R3-NH2
(4)

(In the formula, R3 is a divalent organic group)
is dissolved in the same polar solvent as above, or added as a powder, taking care to avoid heat generation and thickening, to obtain a telechelic oligomer with amino group terminals. The reaction temperature at this time is -
A temperature range of 15 to 120°C is suitable, preferably -15°C.
~100°C, more preferably -15~50°C is suitable. The reaction time is preferably 1 to 5 hours. In this reaction solution,
Acid anhydride represented by general formula (5);

[0023]

[Chemical formula 18]

(In the formula, R4 is an organic group having thermal crosslinking reactivity) is added to terminate the terminal to form an oligoester amide represented by the following general formula (6), which is a precursor of a new thermosetting oligomer. Get acid.

[0025]

[Chemical formula 19]

(wherein R1 and R2 are divalent organic groups,
R3 is a tetravalent organic group, R4 is an organic group having thermal crosslinking reactivity, and R1 and R3 may be the same or different. X is 1 to 30, Y
represents a positive integer from 0 to 30. ) The temperature at this time is 0~
120°C is suitable, more preferably 0 to 100°C,
More preferably it is 40-100°C. Reaction time is 1~
About 5 hours is preferable.

[0027] Thereafter, a non-solvent is added to thermally ring-close and dehydrate the oligoester amic acid solution, followed by conversion to an ester imide oligomer under reflux and azeotropy. As the non-solvent used here, aromatic hydrocarbons such as xylene and toluene can be used, but toluene is preferably used. The reaction is azeotropic, distilling off the water
Reflux using a Stark reflux until the reaction stoichiometric amount of water is collected. Furthermore, a chemical ring closure method can also be used in combination. Examples of the dehydration ring-closing agent used here include aliphatic acid anhydrides such as acetic anhydride, aromatic acid anhydrides such as phthalic anhydride, and chloroacetic acid. In addition, as a dehydration catalyst, for example, an aliphatic tertiary catalyst such as triethylamine can be used.
Examples include heterocyclic tertiary amines such as pyridine, picolines, and isoquinoline. After the reaction, the esterimide oligomer is precipitated as a powder by pouring the oligoesterimide solution into water or an alcoholic solvent with vigorous stirring. The powder is collected by filtration and then dried under reduced pressure at about 80° C. for 48 hours.

As the ester group-containing tetracarboxylic dianhydride used in the present invention, ester group-containing tetracarboxylic dianhydrides having any structure can be used, but
These are USP 3182073, Journal of Polymer Science, Part 1, 1531
pp (1976), JP-A-1-254631, and JP-A-2-138341, it can also be synthesized using known techniques. That is, in an inert gas atmosphere such as argon or nitrogen, trimellitic acid chloride is dissolved in an organic solvent, and the general formula (7) is dissolved in the solution.

[0029]

[Chemical formula 20] HO-R1-OH (7)

00
A diol represented by the formula (wherein R1 is a divalent organic group), an amine, and an organic solvent are added while paying attention to the state of the reaction system. As the amine used as a scavenger for the reaction by-product hydrogen chloride, tertiary amines such as pyridine and triethylamine can be used, but pyridine is preferably used. Further, as the organic solvent, aromatic hydrocarbons such as xylene and toluene can be used, but toluene is preferably used. The reaction temperature at this time is -15~
The range of 120°C is suitable, more preferably 0 to 10
The temperature is 0°C, more preferably 40 to 100°C. The reaction time is preferably 1 to 3 hours. Thereafter, it is converted into an ester group-containing acid dianhydride under reflux conditions. After the reaction, the reaction system is sufficiently cooled, the precipitated salt is filtered off, the filtrate is collected, and the solvent is distilled off under reduced pressure to obtain crystals of the ester group-containing acid dianhydride. This was recrystallized from acetic anhydride, and the crystals were collected at 80°C.
Dry in vacuum for 48 hours.

R1 in the general formula (7) is a divalent organic group, preferably an aromatic group. Specific examples of this R1 group include the following, at least one of which is selected.

[0032]

[C21]

More specifically, from the viewpoint of balance of various characteristics,

[0034]

[Chemical formula 22]

It is preferable that at least one of the following is the main component. Furthermore, as the organic tetracarboxylic dianhydride that can be used in combination with the ester group-containing tetracarboxylic dianhydride in the present invention, organic tetracarboxylic dianhydrides of any structure can be used, but those of general formula (3) R2 of
The group is a tetravalent organic group, preferably an aromatic group. Specific examples of R2 include the following, and at least one of these is selected.

[0036]

[C23]

[0037]

[C24]

These organic tetracarboxylic dianhydrides may be used alone or in combination of two or more. More specifically, from the perspective of the balance of various characteristics,

[0039]

[C25]

It is preferable that at least one of the following is used as a main component. Further, as the divalent organic group R3 in the organic diamine compound represented by the general formula (4) used in the present invention, essentially any divalent organic group can be used.
Specifically, the following may be mentioned, and at least one of these is selected.

[0041]

[C26]

[0042]

[C27]

[0043]

[C28]

[0044] Among these, aromatic groups are preferable, and specifically,

[0045]

[C29]

It is preferable that the main component is at least one of the following.

The acid anhydride used in the present invention for terminal termination has the general formula (5)

[0048]

[C30]

It is preferably an aromatic group represented by
Examples of R4 of the aromatic acid anhydride include:

[0050]

[Chemical formula 31]

[0051] From the viewpoint of cost and handling, particularly preferred are:

[0052]

[C32]

##EQU1## is used. Examples of organic solvents used in the production reaction of the esterimide oligomer solution include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide, N,N'-dimethylformamide,
Examples include formamide solvents such as N,N'-diethylformamide, and acetamide solvents such as N,N'-dimethylacetamide and N,N'-diethylacetamide. These solvents can be used alone or as a mixed solvent of two or more. Furthermore, it can also be used as a mixed solvent with a non-solvent for polyamic acid such as methanol, ethanol, isopropanol, benzene, methyl cellosolve, etc. together with these polar solvents.

The mechanism behind the particularly high heat resistance of the reactive oligoesterimide according to the present invention is not clear, but it is due to thermal curing of acetylene (thermal trimerization).
This is thought to be the effect of the formation of an aromatic ring due to the formation of a benzene skeleton due to the formation of a benzene skeleton or the formation of a tetrabenzocyclooctadiene skeleton due to thermal curing of biphenylene [for example,
J. K. Still et al., Macromolecules, Volume 19,
No. 8, page 1985, 1986]. In addition, the number average degree of polymerization [DP; P. J. Flory, Principle
es of Polymer Chemistry:
Cornell University Press:
Ithaca, NY, p. 91, 1953], the copolymerization ratio X is 1 to 30, Y is 0 to 30, preferably 1 to 15, more preferably 1 to 1.
0 is good. If it exceeds 30, there will be a drawback that the solubility in organic solvents will decrease. Moreover, if it is less than 1, problems may arise in terms of mechanical strength.

When obtaining a cured product from the novel thermosetting oligomer of the present invention, known epoxy resins, epoxy resin curing agents, curing accelerators, fillers, flame retardants, reinforcing agents, surface treatment agents, and pigments may be used as necessary. , various elastomers, etc. can be used in combination.

Epoxy resin is a compound having two or more epoxy (glycidyl) groups in its molecule; examples include bisphenol A, bisphenol F, hydroquinone, resorcinol, flurglycine, tris(4-hydroxyphenyl)methane, , 1,2,2,-tetrakis(4-hydroxyphenyl)ethane and other dihydric or trihydric or higher phenols, or halogenated polyphenols such as tetrabromobisphenol A and novolacs derived from brominated polyphenols. glycidyl ether compounds, phenol, novolac epoxy resins which are reaction products of phenols such as ortho-cresol and formaldehyde, aniline, para-aminophenol, meta-aminophenol, 4-amino-metacresol, 6-amino-metacresol, 4,4'
-diaminodiphenylmethane, 8,8'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 1,4-bis(4-aminophenoxy)benzene, 1,4-bis(
3-aminophenoxy)benzene, 1,3-bis(3-
Aminophenoxy)benzene, 2,2-bis(4-aminophenoxyphenyl)propane, paraphenylenediamine, metaphenylenediamine, 2,4-toluenediamine, 2,6-toluenediamine, paraxylylenediamine, metaxylylenediamine , 1,4-cyclohexane-bis(methylamine), 1,3-cyclohexane-
Bis(methylamine), 5-amino-1-(4'-aminophenyl)-1,8,8-trimethylindane, 6-
Amine-based epoxy resins derived from amino-1-(4-aminophenyl)-1,8,8-trimethylindane, etc., glycidyl esters derived from aromatic carboxylic acids such as paraoxybenzoic acid, terephthalic acid, isophthalic acid, etc. hydantoin-based epoxy resin derived from 5,5-dimethylhydantoin etc., 2,2'-bis(
3,4-epoxycyclohexyl)propane, 2,2-
Bis[4-(2,3-epoxypropyl)cyclohexyl]propane, vinylcyclohexane dioxide, 3
, 4-epoxycyclohexanecarboxylate, and one or more of triglycidyl isocyanurate, 2,4,6-triglycidoxy-s-triazine, and the like. Examples of known epoxy curing agents include amine curing agents such as aromatic amines and aliphatic amines such as xylylene diamine, polyphenol compounds such as phenol novolak and cresol novolac, and hydrazide compounds.

Examples of curing accelerators include amines such as benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and 1,8-diazabicycloundecene, and 2-ethyl-4-methylimidazole. Examples include imidazole compounds and boron trifluoride amine complexes.

Addition of known elastomers to improve mechanical strength is also effective. Specific examples of known elastomers include the following.

[0059]

[Chemical formula 33]

The elastomer described above is Silast
ic (LS-420), Sylgard (184)
is from Dow Corning, Hiker ATBN (1
300 x 16 etc.), CTB (2000 x 162),
CTBN (1300×13, 1300×8, 13
00 × 31) and VTBN (1300 × 23) can be purchased from Ube Industries, Ltd., and 3F can be purchased from Monsanto. The inorganic filler used is water-insoluble and insulating. Examples include silica, alumina, zirconia, titanium dioxide, metal oxides such as zinc white, metal hydroxides such as magnesium hydroxide and aluminum hydroxide, talc,
These include natural minerals such as kaolin, mica, wollastonite, and clay minerals, and insoluble salts such as calcium carbonate, magnesium carbonate, barium sulfate, and calcium phosphate. As reinforcing materials, carbon fiber, glass fiber, aramid fiber, liquid crystal polyester fiber such as Vectra, polybenzothiazole (PB
T) Examples include nonwoven fabrics, mats, paper, and combinations thereof made of fibers, alumina fibers, etc.

[0061]

[Examples] Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples in any way, and the present invention may be practiced without departing from the spirit thereof. Various modifications, improvements, and improvements have been made based on the knowledge of those skilled in the art.
It can be implemented in a modified manner.

Reference Example 1 A 1-liter three-necked flask was equipped with a three-way cock, a Dimroth reflux condenser, and a dropping funnel. After thoroughly drying the reaction system and purging it with nitrogen, 42.1g (200mmol
) and 250 ml of dry toluene (dried on a sodium wire) were placed in a flask and heated to 100°C in an oil bath to dissolve the trimellitic acid chloride. 22.8g (100m
mol) of bisphenol A, 20 ml of dry pyridine, and 100 ml of dry toluene were added dropwise over 15 minutes while paying attention to the state of the reaction system, and then allowed to react for 30 minutes. Thereafter, the mixture was allowed to react under reflux for 3 hours. After the reaction was completed, the reaction system was sufficiently cooled, and the precipitated white precipitate of pyridinium salt was filtered off by suction filtration. When the filtrate was collected and the solvent was distilled off under reduced pressure using an evaporator, 57
．． 2 g (yield: 99%) of white crystals were precipitated. When this was recrystallized from acetic anhydride, 16.3 g of the target compound was obtained. The melting point is 190-191℃ (literature value 192℃
)Met. In addition, the following formula obtained

[0063]

[C34]

The elemental analysis value of the tetracarboxylic dianhydride shown as CHO is calculated value (%): C; 68.75 H; 3.47 Actual value (%); C; 68.49 H; 3 .52, and the spectrum data is IR (KBr, cm-1)
=3430, 2980, 1850, 1840,
1780, 1740, 1620, 1500, 1
230, 1170, 1100, 1050, 10
20, 930, 900, 880, 720, 6
201H-NMR (acetone, ppm) δ=
1.83 (S, 6H, -CH3)7.3 (m,
8H, Ph −H) 8.3 (m, 2H, Ph
-H) 8.8 (m, 4H, Ph -H)

0
Example 1 A 1 liter four-necked flask was equipped with a three-way cock, a Dean-Stark distiller, a Dimroth reflux condenser, a dropping funnel, and a serum cap. After drying the reactor under reduced pressure and thoroughly purging with nitrogen, the following formula obtained in Reference Example 1

[
0066

[C35]

5.77 g (10
mmol) and 30 ml of dry dimethylformamide (hereinafter referred to as DMF) were charged into the reaction system and cooled on ice. next,

0
068]

[C36]

5.84g of diamine (20mm
ol) in 20 ml of DMF was placed in a dropping funnel and added to the reaction system while being careful to avoid heat generation. 0℃
After reacting for 1 hour at 60℃ and 0.5 hour at 60℃, the following formula

[
0070

[C37]

3.28 g (2
0 mmol) was dissolved in 10 ml of DMF and added to the reaction system. After reacting at 60° C. for 0.5 hour, 150 ml of toluene was added. The reaction was carried out under reflux for 45 hours, and 0.70 ml (theoretical value: 0.72 ml) of water was distilled off under toluene azeotropy. After the reaction, the reaction solution was poured into 500 ml of methanol to precipitate the imide oligomer. The precipitated oligomer was filtered under reduced pressure and dried in vacuo at 80° C. for 48 hours to obtain 13.08 g (yield: 92.3%) of a pale yellow powder. This imide oligomer is 4.0
When press-molded for 2.0 hours at 230°C under contact pressure using g, the result was 12 mm (width) x 12 cm (length) x 1.2
A casting plate with a thickness of mm (thickness) was obtained. Tables 1 and 2 show the results of various physical property measurements of the oligomer and casting plate.

Example 2 Aromatic acid dianhydride (A) 5.77g (10mmol)

[
0073

[C38]

Aromatic acid dianhydride (B) 4.44g (10
mmol)

[0075]

[C39]

3.28 g (20 mmo) of aromatic primary amine
l)

[0077]

[C40]

Aromatic acid anhydride 3.28g (20mmol
)

[0079]

[C41]

A reaction was carried out under the same conditions as in Example 1 using [0080] to obtain 24.49 g (yield: 90.6%) of ester imide oligomer. Press molding was performed using 4.0 g of the above ester imide oligomer under the same conditions as in Example 1, and the result was 12 mm (width) x 12 cm (length) x 1.2 m.
A casting plate having a thickness of m (thickness) was obtained. Tables 1 and 2 show the results of measuring various physical properties of the oligomer and its casting plate.

Comparative Example 1 4.5 g of a commercially available imide type thermosetting oligomer was press-molded at 230° C. and 10 kg/cm 2 for 1.5 hours, resulting in a size of 12 mm (width) x 12 cm (length) x 1.
A casting plate with a thickness of 2 mm was obtained. Tables 1 and 2 show the results of measuring various physical properties of the imide type thermosetting oligomer and its casting plate.

[0082]

[Table 1]

[0083]

[Table 2]

[0084]

Effects of the Invention By using the reactive ester imide oligomer according to the present invention, it is possible to obtain a cured product that has excellent processing properties due to high resin fluidity and has an extremely high heat resistance that has never been seen before. Furthermore, the reactive ester imide oligomer according to the present invention has excellent mechanical strength, dimensional stability, electrical properties, and the like. In particular, it is possible to obtain a polyesterimide that has excellent solubility in solvents, adhesion with other substances, and flexibility, and is less likely to cause voids or cracks in molded products. As mentioned above, since the reactive ester imide oligomer of the present invention has many characteristics as described above, it can be used as a laminate,
It is possible to provide a material with extremely high industrial value for a wide range of applications such as heat-resistant paints, polymeric materials for electronic devices, and molding materials, and its usefulness is extremely large.

Claims (7)

[Claims] Claim 1: General formula (1) [Formula 1] (wherein, R1 and R3 are divalent organic groups, R2 is a tetravalent organic group, and R4 is an organic group having thermal crosslinking reactivity. , R1 and R3 may be the same or different. X represents a positive integer of 1 to 30, and Y represents a positive integer of 0 to 30. 2. The oligomer according to claim 1, wherein R1 is at least one selected from the following groups. [Case 2] 3. The oligomer according to claim 1, wherein R2 is at least one selected from the following groups. [Chemical formula 3] 4. The oligomer according to claim 1, wherein R3 is at least one selected from the following groups. [C4] 5. The oligomer according to claim 1, wherein R4 is at least one selected from the following groups. [C5] 6. The reaction system is kept below room temperature in an inert gas atmosphere, and the following general formula (
2), or the ester group-containing acid dianhydride and the organic tetracarboxylic dianhydride represented by the general formula (3) [Formula 6] (wherein, R1 is divalent (organic group) [Formula 7] (in the formula, R2 is a tetravalent organic group) is dissolved in a solution,
The following general formula (4) dissolved in an aprotic polar solvent
Diamine represented by [Formula 8] H2N-R3-NH2
(4) (wherein R3 is a divalent organic group) is added and reacted in an amount necessary to obtain a telechelic oligoester amic acid terminated at both ends, and then the general formula ( 5) An acid anhydride represented by formula 9 (wherein R4 is an organic group having thermal crosslinking reactivity) is added to terminate the terminal, and then a nonsolvent is added to thermally ring-close/close the ring under azeotropy. A method for producing a novel thermosetting oligomer characterized by dehydration. 7. The method according to claim 6, wherein the aprotic polar solvent is dimethylformamide.