Functional monomaleimide and thermosetting composition therefrom

Novel N-(meth)allyloxyphenylmaleimides are prepolymerized with at least one bis-imide and formulated, together with at least one imidazole compound, into thermosetting compositions useful for the production of a wide variety of shaped articles having improved mechanical properties.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to novel maleimido compounds and to novel 
thermosetting compositions comprised thereof, the polymerizates of which 
have improved mechanical properties. 
2. Description of the Prior Art 
N-Substituted maleimides are a known family of chemical compounds and the 
N,N'-disubstituted bismaleimides are especially useful for the preparation 
of thermosetting polymers, the polybis-maleimides. 
Monomaleimides are also known to this art. Thus, U.S. Pat. No. 2,444,536 
describes a process for the preparation of N-arylmaleimides. 
Certain monomaleimides can be used in agrochemistry, as insecticides or 
fungicides. Others may serve to prepare polymers which can be crosslinked 
under the influence of light. 
Monomaleimides can also be used in mixtures with bis-maleimides for the 
production of thermosetting polymers. 
SUMMARY OF THE INVENTION 
A major object of the present invention is the provision of a novel class 
of monomaleimides having the general formula (I): 
##STR1## 
in which R represents a hydrogen atom or a methyl radical. 
These novel monomaleimides comprise: 
N-(2-allyloxyphenyl)maleimide, 
N-(3-allyloxyphenyl)maleimide, 
N-(4-allyloxyphenyl)maleimide, 
N-(2-methallyloxyphenyl)maleimide, 
N-(3-methallyloxyphenyl)maleimide, 
N-(4-methallyloxyphenyl)maleimide. 
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION 
More particularly according to the present invention, the subject 
maleimides of the formula (I) may be prepared especially from aminophenols 
(ortho-, meta- or para-), according to the Claisen reaction. 
For example, aminophenol, the amino group of which has been previously 
blocked by reaction with acetic anhydride to form acetamidophenol, may be 
reacted with an allyl- or a methallyl halide (most frequently, bromide), 
as the case may be, in solution in acetone and in the presence of 
dipotassium carbonate. The amino group is later regenerated by hydrolysis. 
The corresponding maleimide is then prepared in conventional manner by 
reacting, in solution, allyloxyaniline or methallyloxyaniline, obtained 
beforehand, with maleic anhydride in the presence of acetic anhydride, 
triethylamine and a nickel salt (nickel acetate in particular). 
N-Allyloxyphenylmaleimide or N-methalyloxyphenyl-maleimide is this 
obtained. 
N-(4-Allyloxyphenyl) maleimide is a mustard yellow-colored solid having a 
melting point of approximately 103.degree. C. 
The NMR results reflect the following structure: 
______________________________________ 
##STR2## 
NMR 1H; solvent: DMSO d6; reference: hexa- 
methyldisiloxane (HMDS) 
______________________________________ 
.delta. 7.16 (2H,m) H 3,5; -.delta. 7.10 (2H,s) maleimido; 
.delta. 6.98 (2H,m) H 2,6; 
.delta. 5.99 (1H,m) CH; 
.delta. 5.35 and 5.22 (2H,dd) 
CH.sub.2 ; 
.delta. 4.55 (2H,d) OCH.sub.2. 
______________________________________ 
N-(3-Allyloxyphenyl) maleimide is a viscous orange-yellow liquid, which 
crystallizes slowly at room temperture and boils at approximately 
150.degree. C. at a pressure of 20 Pa. 
The NMR results reflect the following structure: 
______________________________________ 
##STR3## 
NMR 1H; solvent: DMSO d6; reference: HMDS 
______________________________________ 
.delta. 6.85; 6.89 and 6.93 (3H,m) 
H4, H2 and H6; 
.delta. 7.10 (2H,s) maleimido; 
.delta. 7.32 (1H,5) H5; 
.delta. 5.99 (1H,m) CH; 
.delta. 5.35 and 5.21 (2H,dd) 
CH.sub.2 ; 
.delta. 4.51 (2H,d) OCH.sub.2. 
______________________________________ 
N-(2-Allyloxyphenyl) maleimide is a pale yellow crystalline solid, having a 
melting point of approximately 82.degree. C. and a boiling point of 
148.degree. C. to 155.degree. C. at a pressure of 20 Pa. 
The NMR results reflect the following structure: 
______________________________________ 
##STR4## 
NMR 1H; solvent: DMSO d6; reference: HMDS 
______________________________________ 
.delta. 7.38 (2H,dt) H5; 
.delta. 7.20 (1H,dd) H3; 
.delta. 7.15 (2H,s) maleimido; 
.delta. 7.09 (1H,dd) H6; 
.delta. 6.99 (1H,dt) H4; 
.delta. 5.83 (1H,m) CH; 
.delta. 5.18 and 5.11 (2H,dd) 
CH.sub.2 ; 
.delta. 4.50 (2H,d) OCH.sub.2. 
______________________________________ 
N-(4-Methallyloxphenyl) maleimide is a beige-colored solid having a melting 
point of 64.degree. C. 
The NMR results reflect the following structure: 
______________________________________ 
##STR5## 
NMR 1H; solvent: DMSO d6; reference: HMDS 
______________________________________ 
.delta. 7.16 (2H,d) H 3,5; 
.delta. 7.09 (2H,s) maleimido; 
.delta. 6.97 (2H,d) H 2,6; 
.delta. 4.90 and 5.00 (1H,s) 
CH.sub.2; 
.delta. 4.45 (2H,s) OCH.sub.2 ; 
.delta. 1.71 (3H,s) CH.sub.3. 
______________________________________ 
N-(3-Methalyloxyphenyl) maleimide is a beige-colored solid having a melting 
point of 39.degree. C. 
The NMR results reflect the following structure: 
______________________________________ 
##STR6## 
NMR 1H; solvent: DMSO d6; reference: HMDS 
______________________________________ 
.delta. 7.32 (1H,t) H5; 
.delta. 7.10 (2H,s) maleimido; 
.delta. 6.94 (1H,d) H6; 
.delta. 6.89 (1H,s) H2; 
.delta. 6.84 (1H,d) H4; 
.delta. 4.90 and 5.00 (1H,1) 
CH.sub.2; 
.delta. 4.42 (2H,s) OCH.sub.2 ; 
.delta. 1.70 (3H,s) CH.sub.3. 
______________________________________ 
N-(2-Methallyloxyphenyl) maleimide is a beige-colored solid having a 
melting point of 96.degree. C. 
The NMR results reflect the following structure: 
______________________________________ 
##STR7## 
NMR 1H; solvent: DMSO d6; reference: HMDS 
______________________________________ 
.delta. 7.36 (1H,t) H5; 
.delta. 7.20 (1H,d) H3; 
.delta. 7.14 (2H,s) maleimido; 
.delta. 7.07 (1H,d) H6; 
.delta. 6.98 (1H,t) H4; 
.delta. 4.82 and 4.88 (1H,s) 
CH.sub.2; 
.delta. 4.39 (2H,2) OCH.sub.2 ; 
.delta. 1.59 (3H,s) CH.sub.3. 
______________________________________ 
The novel monomaleimides of the general formula (I), when they are used 
with one or more bis-maleimides to prepare thermosetting compositions for 
molding or for impregnation, impart to such compositions improved 
mechanical properties compared with compositions which have been prepared 
without these novel monomaleimides. 
More precisely, the present invention also features novel thermosetting 
compositions, characterized in that they are comprised of: 
(A) a prepolymer obtained by reaction between 50.degree. C. and 300.degree. 
C. of: 
(a) a bis-imide or a combination of several bis-imides of the general 
formula (II): 
##STR8## 
in which: 
Y represents a hydrogen atom or a methyl group; 
L represents a divalent hydrocarbon radical, such as a cyclohexylene 
radical; a phenylene radical; the 4-methyl-1,3-phenylene radical; the 
2-methyl-1,3-phenyl radical; the 5-methyl-1,3-phenylene radical; the 
2,5-diethyl3-methyl-1,4-phenylene radical: and the radicals of the formula 
(III): 
##STR9## 
in which: 
T represents a simple valency bond or one of the following atoms or groups; 
##STR10## 
X represents a hydrogen atom, a methyl, ethyl or isopropyl radical; with 
(b) one or more monomaleimides of the general formula (I): 
##STR11## 
in which R represents a hydrogen atom or a methyl radical; and, if 
appropriate, with 
(c) an organosilicic compound containing at least one hydroxyl group bonded 
to a silicon atom in its molecule; and 
(B) imidazole or an imidazole derivative. 
Exemplary of the bis-maleimides of the formula (II), representative are: 
N,N'-meta-phenylene-bis-maleimide; 
N,N'-para-phenylene-bis-maleimide; 
N,N'-4,4'-diphenylmethane-bis-maleimide; 
N,N'-4,4'-diphenylether-bis-maleimide; 
N,N'-4,4'-diphenylsulfone-bis-maleimide; 
N,N'-1,4-cyclohexylene-bis-maleimide; 
N,N'-4,4'-(1,1-diphenylcyclohexylidene)bis-maleimide; 
N,N'-4,4'-(2,2-diphenylpropane)bis-maleimide; 
N,N'-4,4'-triphenylmethane-bis-maleimide; 
N,N'-1,3-(4-methylphenylene)bis-maleimide; 
N,N'-1,3-(2-methylphenylene)bis-maleimide. 
Among these bis-maleimides, particularly preferred are 
N,N'-4,4'-diphenylmethane-bis-maleimide, 
N,N'-1,3-(4-methylphenylene)bis-maleimide, 
N,N'-1,3-(2-methylphenylene)bis-maleimide, and mixtures thereof. 
These bis-maleimides can be prepared according to the processes described 
in U.S. Pat. No. 3,018,290 and British Pat. No. 1,137,290. 
The monomaleimide of the general formula (I) is preferably: 
N-(2-allyloxyphenyl)maleimide; 
N-(3-allyloxyphenyl)maleimide; 
N-(4-allyloxyphenyl)maleimide; 
N-(2-methallyloxyphenyl)maleimide; 
N-(3-methallyloxyphenyl)maleimide; 
N-(4-methallyloxyphenyl)maleimide; and mixtures thereof. 
The hydroxylated organosilicic compounds, which optionally comprise the 
subject compositions, are known compounds of the following general formula 
(IV): 
##STR12## 
in which R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5, which may be 
identical or different, represent: 
(i) a hydroxyl group or a group of the type-OR.sub.6 in which R.sub.6 may 
be a straight or branched chain alkyl radical containing 1 to 6 carbon 
atoms or a phenyl radical; 
(ii) a hydrogen atom; 
(iii) a straight or branched chain alkyl radical containing 1 to 6 carbon 
atoms which may be optionally substituted with one or more chlorine or 
fluorine atoms or with a -CN group; 
(iv) a straight or branched chain alkenyl radical containing 2 to 6 carbon 
atoms; 
(v) a phenyl radical, optionally substituted with one or more alkyl and/or 
alkoxy radicals containing 1 to 4 carbon atoms, or with one or more 
chlorine atoms; and y is an integer or a fractional number from 0 to 1000. 
For an organosilicic compound defined by formula (IV), y is, in fact, 
always an integer, but as in this case compounds having a polymeric 
structure (when y is greater than 1) are concerned, it is rare that a 
single compound is obtained, but most frequently a mixture of compounds of 
the same chemical structure, which differ by the number of recurring units 
in their molecule is obtained; this leads to a mean value for y, which may 
be an integer or a fractional number. 
The hydroxylated organosilicic compounds of the type mentioned above can be 
characterized by the ratio of the weight of the hydroxyl groups they 
contain to the total weight of their molecule. 
The use of a hydroxylated organosilicic compound is a measure which 
especially facilitates, during the preparation of the thermosetting 
compositions according to the present invention, the transition of the 
compounds with maleimide groups to the molten state and it also makes it 
possible to impart a greater fluidity to the thermosetting resin in the 
molten state. 
When the organosilicic compounds in fact are present, the compounds which 
are preferred are those mentioned above in which the ratio by weight of 
the hydroxyl groups in the molecule is at least 0.05% and preferably 0.1%. 
Among the organosilicic compounds of this preferred group, those which are 
particularly well suited are the compounds of the formula (IV) in which: 
R.sub.1, R.sub.2, R.sub.3 and R.sub.4, which may be identical or different, 
represent a straight or branched chain alkyl radical containing 1 to 6 
carbon atoms or a straight or branched chain alkenyl radical containing 2 
to 6 carbon atoms or a phenyl radical; 
R.sub.5 represents a hydroxyl group; and y is an integer or a fractional 
number, from 0 to 250. 
This circumscribes, therefore, silane-diols when y is 0 or, 
polysiloxane-diols when y is other than 0. 
For the preparation thereof, see W. NOLL: Chemistry and Technology of 
Silicones (English translation of the German edition of 1968), published 
by Academic Press of New York. 
The organosilicic compounds which are particularly suitable are: 
diethylsilane-diol; 
diphenylsilane-diol; 
methylphenylsilane-diol; 
1,1,3,3-tetramethyldisiloxane-1,3-diol; 
1,1-dimethyl-3,3-diphenyldisiloxane-1,3-diol; 
1,3-dimethyl-1,3-diphenyldisiloxane-1,3-diol; 
1,1,3,3,5,5-hexamethyltrisiloxane-1,5-diol; 
1,1,3,3,5,5,7,7-octamethyltetrasiloxane-1,7-diol; 
1,1,3,3,5,5,7,7,9,9-decamethylpentasiloxane-1,9-diol; 
1,1,3,3,5,5,7,7,9,9,11,11-dodecamethylhexasiloxane-1,11-diol; 
1,3,5,7,9-pentamethyl-1,3,5,7,9-pentaphenylpentasiloxane-1,9-diol; 
and the corresponding higher members of the series. 
The hydroxylated organosilicic compounds which are especially well suited 
may also be mixtures of two or more of the compounds mentioned above. 
Thus, commercially available hydroxylated polysiloxane oils or resins may 
be used for convenience. These are, especially, 
.alpha.,.omega.-dihydroxylated polymethylpolysiloxane oils containing from 
0.2 to 0.3% by weight of hydroxyl groups (Rhone-Poulenc 48V 500 oil), or 
10 to 12% by weight of hydroxyl groups (Rhone-Poulenc 48V 50 oil) or 
.alpha.,.omega.-dihydroxylated methylphenylpolysiloxane oils or resins 
containing 4.5% to 5% by weight of hydroxyl groups (Rhone-Poulenc oil 
50606) or from 7.5 to 8.5% by weight of hydroxyl groups (Rhone-Poulenc 
resin 50305); these commercially available oils or resins are given by way 
of example, but there are others which may be just as suitable. 
In the prepolymers (A) prepared from one or more bis-imides of formula (II) 
and from one or more monomaleimides of formula (I), the amounts of 
reagents are selected such as to obtain, by weight in relation to the 
total weight of these different constituents: 
from 50 to 95% of bis-imide(s), and 
from 5 to 50% monomaleimide(s). 
In the prepolymers (A) prepared from one or more bis-imides of formula 
(II), from one or more monomaleimides of formula (I) and a hydroxylated 
organosilicic compound of formula (IV), the amounts of reagents are 
selected such as to obtain, by weight in relation to the total weight of 
these different constituents: 
from 40 to 90% of bis-imide(s), from 5 to 40% of monomaleimide(s), and from 
5 to 40% of the hydroxylated organosilicic compound. 
To obtain compositions according to the invention of this type which have 
superior flexural properties when heated, it is preferable to use a 
proportion of the organosilicic compound of 5 to 20% (by weight) of the 
total weight of bis-imide(s), monomaleimide(s) and the hydroxylated 
organosilicic compound. 
The imidazole derivative (B) advantageously has the general formula (V): 
##STR13## 
in which R.sub.7, R.sub.8, R.sub.9 and R.sub.10, which may be identical or 
different, represent: a hydrogen atom, an alkyl or alkoxy radical 
containing 1 to 20 carbon atoms, a vinyl radical, a phenyl radical, a 
nitro group, R.sub.9 being capable of forming with R.sub.10 and the carbon 
atoms to which these radicals are linked, a single ring such as, for 
example, a benzene ring, R.sub.7 may also represent a carbonyl group 
linked to a second imidazole ring. 
As specific examples of such imidazole derivatives, representative are 
imidazole or glyoxaline, 1-methylimidazole, 2-methylimidazole, 
1,2-dimethylimidazole, 1-vinylimidazole, 1-vinyl-2-methylimidazole, 
benzimidazole and carbonyldiimidazole. 
The imidazole derivative is used in catalytic quantities. According to the 
nature of the imidazole derivative and according to the rate of 
polymerization desired at the time of use, the imidazole derivative is 
used at a proportion of between 0.02 and 1% by weight relative to the 
prepolymer (A). 
An imidazole proportion of 0.05 to 0.5% by weight relative to the 
prepolymer (A) is preferably used. 
The compositions according to the invention may also contain a 
N,N',N"-tris(hydroxyalkyl)hexahydrotriazine; 
N,N',N'-tris(hydroxyethyl)hexahydro-1,3,5-triazine, 
N,N',N"-tris(hydroxypropyl)hexahydro-1,3,5-triazine and 
N,N',N"-tris(hydroxybutyl)hexahydro-1,3,5-triazine are the preferred. 
N,N',N"-Tris(hydroxyethyl)hexahydro-1,3,5-triazine, which is commercially 
available, is preferably used. 
N,N',N"-Tris(hydroxyalkyl)hexahydrotriazine, when it is present, confers on 
the thermosetting compositions a higher pegosity and an improvement of the 
thermomechanical properties, especially of flexural strength. 
From 0 to 5% by weight of N,N',N"-tris(hydroxyalkyl)hexahydrotriazine 
relative to the prepolymer (A) is typically used. 
To obtain a good efficiency, it is preferable to use from 0.5 to 2% by 
weight of N,N',N"-tris(hydroxyalkyl)hexahydrotriazine relative to the 
prepolymer (A). 
The compositions according to the invention, after heat treatment, provide 
mechanical properties, especially flexural, at ambient temperature and on 
heating (usually 250.degree. C.) which are superior to those obtained with 
prior compositions, such as those described in French Patent Application 
No. 83/17,218, published under No. 2,553,780. 
Various adjuvants may also be incorporated into the compositions according 
to the invention. These adjuvants which are commonly used and are well 
known to those skilled in this art may be, for example, stabilizers or 
degradation inhibitors, lubricants or stripping agents, colorants or 
pigments, powdery or particle fillers such as silicates, carbonates, 
kaolin, chalk, ground quartz, mica or glass microbeads, etc. Adjuvants 
which modify the physical structure of the product obtained such as, for 
example, porogenous agents or fibrous reinforcing agents: fibrils of 
carbon, polyimide, aromatic polyamides, whiskers, etc. may also be 
incorporated. 
The manufacturing process is such that the thermosetting resin which is 
ready for use is sufficiently supple and sticky in a thin layer. 
Additionally, to obtain a homogeneous material after lamination, reactions 
which give rise to highly volatile compounds at the treatment temperatures 
should be limited. To this end, when the initial reagents contain a 
silanediol, it is desirable to first carry out the major part of the 
oligomerization reaction yielding water as by-product; this water can be 
removed more easily during the course of the manufacture of the resin. 
Firstly, an intimate mixing of the compounds with the maleimide groups and, 
if appropriate, the hydroxylated organosilicic compound is carried out. In 
order to avoid a premature homopolymerization of maleimides which would 
give rise to a resin which is too viscous, the maleimides +(if 
appropriate) hydroxylated organosilicic compound mixture is melted in the 
absence of a catalyst at a temperature not exceeding the melting point of 
the most difficult maleimide to liquefy. If the reaction mixture contains 
an organo-silicic compound with a high content of hydroxyl groups, the 
mixture is, in this case, maintained in the molten state such as to carry 
out a part of the oligomerization of the silanediol; preferably, this 
compound is heated to about 150.degree. C. until approximately 40% of the 
initial hydroxyl groups have disappeared during the oligomerization of 
this compound. In another embodiment, this oligomerization could be 
carried out before the introduction of the compounds having maleimide 
groups. 
The imidazole derivative (B) and the 
N,N',N"-tris(hydroxyalkyl)hexahydrotriazine where appropriate, are then 
added to the mixture which is well stirred, such as to enable their rapid 
dispersion. 
When the catalyst is particularly active, it is desirable to add it with a 
solvent which is compatible with the reaction medium in order to avoid its 
encapsulation in the polymer network which it generates. Thus, a solvent 
such as triallyl isocyanurate, diallyl phthalate or allyl benzoate can be 
used. 
A volatile solvent which will be eliminated later by evaporation under 
reduced pressure can also be used. In fact, the mixture is degassed to 
eliminate volatile products which are undesirable for the preparation of 
the laminates. The mixture is cast immediately after homogenization. 
The thermosetting compositions according to the invention have a sufficient 
pegosity for applications such as laminates and composite materials. 
The compositions can be used in molding or impregnation procedures. They 
can be used for the production of coatings, gluings, laminates and 
reinforced composite materials. The reinforcing material can be in the 
form of woven or unwoven sheets, of unidirectional elements or of natural 
or synthetic cut fibers such as filaments or fibers of glass, boron, 
carbon, tungsten, silicon, polyamide-imides or aromatic polyamides. The 
compositions are of special value in obtaining intermediate articles which 
are preimpregnated without a solvent. The impregnation of the fibrous 
material may be carried out using common techniques such as dip-coating, 
coating with a doctor blade or with curtain or impregnation by transfer. 
The transferable film and the preimpregnated articles may be used directly 
or stored for later use; they retain their properties very satisfactorily 
during a cold storage between 0.degree. and 10.degree. C. 
The impregnated materials can be used for making parts of various shapes 
and uses in numerous industries, such as, for example, in aeronautics. 
These parts, which may be revolving parts, are obtained by placing several 
layers of prepregs on a shape or a support. 
Crosslinking is then carried out under the usual technological conditions 
relating to composite materials, and, in particular, at temperatures of 
from 100.degree. to 300.degree. C. 
The prepregs can also be used as reinforcements or as means for repairing 
deteriorated parts. 
However, it is also possible to produce parts according to the techniques 
of filament winding, with or without support, or by injection molding, or 
by pultrusion. 
Thus, shaped products having high mechanical and thermal resistance may 
facilely be obtained. 
In order to further illustrate the present invention and the advantages 
thereof, the following specific examples are given, it being understood 
that same are intended only as illustrative and in nowise limitative.

EXAMPLE 1 
Preparation of N-(4-allyloxyphenyl)maleimide 
The title compound was prepared from para-allyloxyaniline, a suitable 
procedure for the preparation of which is featured in J.A.C.S., 44, pp. 
1741-44 (1922). 
Into a glass reactor, equipped with a central stirrer, a thermometer and an 
ascending coolant, maintained at 50.degree. C. under stirring and in which 
a slow stream of nitrogen was circulated: 
(i) 249 g of an acetone solution containing 149.0 g of 
para-allyloxyaniline; and 
(ii) 249 g of an acetone solution containing 112.7 g of maleic anhydride; 
were simultaneously introduced over the course of 20 minutes, by means of 
two dropping funnels. 
The reaction was exothermic and gave the immediate formation of a yellowish 
suspension. 
When the additions were complete, each funnel was rinsed with acetone (10 
cc), the contents of each of which were then added to the reaction mass, 
still maintained under stirring. 
The dropping funnel which previously contained the maleic anhydride, was 
charged with 163.2 of acetic anhydride and the other funnel was charged 
with 45.4 g of triethylamine. 
These two compounds were then introduced into the reactor over the course 
of 5 minutes and an aqueous solution (1.9 cc) containing 0.0528 mole of 
nickel acetate per 100 cc of solution was then added thereto. 
The reaction mixture was maintained at the reflux temperature, under 
stirring, for 2 hr, 30 min. The temperature was then decreased to 
30.degree. C., 1349 g of distilled water were added and the mixture was 
then cooled to 15.degree. C. under stirring. 
The dark yellow precipitate was drained, washed with an 80:20 (v/v) mixture 
of acetone:water (100 cc), which had previously been cooled to 10.degree. 
C., and then with distilled water (100 cc). 
The drained solid was dried for 15 hr at 40.degree. C. under reduced 
pressure (30 Pa). 
215.5 g of a powdery material having a mustard yellow color and an m.p. of 
103.degree. C. were thus obtained. 
The NMR spectrum corresponded to the structure of 
N-(4-allyloxyphenyl)maleimide. 
EXAMPLE 2 
Preparation of N-(3-allyloxyphenyl)maleimide 
The same apparatus as in Example 1 was used and the same procedure was 
followed. 
The starting material was meta-allyloxyaniline, a procedure for the 
preparation of which is described in Chemical Abstracts, 51, 4423 a to g 
(1957). 
The amounts used very twice those used in Example 1: 
(i) 498 g of an acetone solution containing 298.0 g of 
meta-allyloxyaniline; 
(ii) 498 g of an acetone solution containing 225.4 g of maleic anhydride; 
(iii) rinsing of each dropping funnel with acetone (20 cc); 
(iv) 326.4 g of acetic anhydride; 
(v) 90.8 g of triethylamine; 
(vi) an aqueous solution (3.8 cc) containing 0.0528 mole of nickel acetate 
per 100 cc of solution; and 
(vii) 2698 g of distilled water. 
The addition of 2698 g of distilled water to the reaction mixture resulted 
in the settling of a dark-colored oil, which was extracted with ethyl 
acetate (3.times.250 cc). The organic layers obtained were combined and 
dried over sodium sulfate. 
After removal of the solvent by drying under reduced pressure (initially at 
about 3000 Pa, and then at about 70 Pa), 464 g of a very dark, thick oil 
containing 0.309 ethylene double bonding per 100 g were obtained. 
22.77 g of this crude product were taken and 0.2 g of hydroquinone was 
added. This was distilled at a pressure of 12 Pa, in a 50 cc reactor 
equipped with a Vigreux column and with a fraction separator. 
14.7 g of a fraction distilling between 150.degree. C. and 155.degree. C. 
at 20 Pa were collected. 
This was a clear, orange-yellow, viscous liquid with an NMR spectrum which 
corresponded to the structure of N-(3-allyloxyphenyl)maleimide. 
EXAMPLE 3 
Preparation of N-(2-allyloxyphenyl)maleimide 
This compound was prepared from 2-allyloxyaniline, itself prepared as in 
J.A.C.S., 70, PAGE 593 (1948). 
Into a glass reactor equipped with a central stirrer, a thermometer and an 
ascending coolant, maintained at 50.degree. C. under stirring and in which 
a slow stream of nitrogen was circulated: 
(i) an acetone solution (443 cc) containing 298 g of 2-allyloxyaniline; and 
(ii) an acetone solution (443 cc) containing 235.2 g of maleic anhydride; 
were introduced simultaneously over the course of 30 minutes, by means of 
2 dropping funnels. 
The reaction was exothermic and gave the immediate formation of a yellowish 
suspension. 
When the additions were complete, each funnel was rinsed with acetone (10 
cc), the contents of each of which were then added to the reaction mass, 
still maintained under stirring. 
The funnel which previously contained the maleic anhydride was charged with 
265.2 g of acetic anhydride, and the other funnel was charged with 60.6 g 
of triethylamine. 
These two compounds were then introduced into the reactor over the course 
of 6 minutes and an aqueous solution (3.8 cc) containing 0.0528 mole of 
nickel acetate per 100 cc of solution was then added thereto. 
The reaction mixture was maintained at the reflux temperature, under 
stirring, for 2 hr, 30 minutes. The temperature was then decreased to 
30.degree. C., 2500 g of distilled water were added and the mixture was 
then cooled to 20.degree. C. under stirring. 
A dark oil rose to the surface of the aqueous phase. The aqueous phase was 
siphoned off and the oily phase was taken up with ethyl acetate (400 cc). 
The organic phase was washed with distilled water (2.times.500 cc) until 
the pH of the water used for washing was equal to 6. The organic phase 
which was separated by decantation was dried over 150 g of anhydrous 
sodium sulfate. 
After removal of the solvent by drying under reduced pressure (initially at 
about 3000 Pa, then at about 70 Pa), 450 g of a very dark thick oil were 
obtained; this was treated with ethyl alcohol (560 cc), the mixture was 
cooled to 5.degree. C. in ice, and filtered. 416 g of a moist 
beige-colored precipitate were obtained. This was dried for 15 hours at 
40.degree. C. under reduced pressure (30 Pa) and 365 g of a beige-colored 
crystalline material having a m.p. of 82.degree. C. were obtained. 
The NMR spectrum corresponded to the structure of 
N-(2-allyloxyphenyl)maleimide. 
EXAMPLE 4 
Preparation of N-(4-methallyloxyphenyl)maleimide 
This compound was prepared from 4-methallyloxyaniline. 
(4.1) 4-methallyloxyaniline: 
This compound was prepared from para-methallyloxyacetamidobenzene. The 
latter compound was obtained by a method analogous to that for the 
preparation of orthoacetamidophenylallyl ether, described in J.A.C.S., 70, 
page (1948), substituting the allyl bromide with methallyl chloride, and 
operating in the presence of a catalytic amount of potassium iodide (10% 
in moles relative to methallyl chloride). 
Into a glass reactor equipped with a central stirrer, a thermometer and an 
ascending coolant; 
(i) 205 g of para-methallyloxyacetamidobenzene; and 
(ii) 5N ethanolic sodium hydroxide (400 cc); were added. After 
homogenization; 
13.6 g of imidazole, which was 20% (in moles) relative to the 
para-methallyloxyacetamidobenzene, were added. 
The reaction mixture was maintained at the reflux temperature, under 
stirring, for 3 hours. 
The reaction mixture was cooled to 20.degree. C. 
The ethanol was removed under reduced pressure (about 70 Pa). 
Ethyl acetate (250 cc) was added to the reaction mass, and the mixture was 
washed with distilled water (2.times.250 cc) until the washings attained a 
pH of 7. 
The ethyl acetate in the organic phase was removed under reduced pressure 
(about 70 Pa) and 165.5 g of the crude product were obtained. 
135.4 g of the purified product were obtained by distillation at 
113.degree. C. at 0.05 mm Hg. 
The NMR spectrum corresponded to the structure of 4-methallyloxyaniline. 
(4.2) N-(4-methallyloxyphenyl)maleimide: 
Into a glass reactor equipped with a central stirrer, a thermometer and an 
ascending coolant, maintained at 50.degree. C., under stirring, and in 
which a slow stream of nitrogen was circulated: 
(i) an acetone solution (52 cc) containing 32.6 g of 4-methallyloxyaniline; 
and 
(ii) an acetone solution (52 cc) containing 22.5 g of maleic anhydride; 
were simultaneously introduced over the course of 15 minutes by means of 
two dropping funnels. 
The reaction was exothermic and gave the immediate formation of a yellowish 
suspension. 
When the additions were complete, each funnel was rinsed with acetone (10 
cc), the contents of each of which were then added to the reaction mass, 
still maintained under stirring. 
The dropping funnel which previously contained the maleic anhydride was 
charged with 26.5 of acetic anhydride and the other funnel was charged 
with 6.1 g of triethylamine. 
These two compounds were then introduced into the reactor over the course 
of 5 minutes and an aqueous solution (0.4 cc) containing 0.0528 mole of 
nickel acetate per 100 cc of solution was then added. 
The reaction mixture was maintained at the reflux temperature, under 
stirring, for 2 hours, 30 minutes. The temperature was then decreased to 
20.degree. C. 
The reaction mixture was precipitated by pouring it slowly into iced water 
(500 cc), under vigorous stirring. 
The precipitate was filtered, washed again with cooled distilled water, and 
dried for 15 hours at 40.degree. C. under reduced pressure (30 Pa). 39.4 g 
of a beige-colored precipitate, having an m.p. of 64.degree. C. were 
obtained. 
The NMR spectrum corresponded to the structure of 
N-(4-methallyloxyphenyl)maleimide. 
EXAMPLE 5 
Preparation of N-(3-methallyloxyphenyl)maleimide 
(5.1) 3-methallvloxvaniline: 
The starting material was meta-methallyloxyacetamidobenzene, which was 
obtained under the same conditions as those described in Example 4, 
paragraph (4.1) for para-methallyloxyacetamidobenzene. 
Into a glass reactor equipped with a central stirrier, a thermometer and an 
ascending coolant: 
(i) 205 g of meta-methallyloxyacetamidobenzene; and 
(ii) 5N ethanolic sodium hydroxide (400 ml); were introduced. 
After homogenization: 
13.6 g of imidazole, which was 20% (in moles) were added. 
The reaction mixture was maintained at the reflux temperature, under 
stirring, for 3 hours. 
The reaction mixture was cooled to 20.degree. C. 
The ethanol was removed under reduced pressure (about 70 Pa). 
Ethyl acetate (250 cc) was added to the reaction mass, and the mixture was 
washed with distilled water (2.times.250 cc) until the washings attained a 
pH of 7. 
The ethyl acetate in the organic phase was removed under reduced pressure 
(about 70 Pa) and 144 g of the crude product were obtained. 
124 g of the purified material were obtained by distillation at 85.degree. 
C. at 0.05 mm Hg. 
The NMR spectrum corresponded to the structure of 3-methallyloxyaniline. 
(5.2) N-(3-methallyloxyphenyl)maleimide: 
Into a glass reactor equipped with a central stirrer, a thermometer and an 
ascending coolant maintained at 50.degree. C., under stirring, and in 
which a slow stream of nitrogen was circulated; 
(i) an acetone solution (105 cc) containing 65.2 g of 
3-methallyloxyaniline; and 
(ii) an acetone solution (105 cc) containing 45.0 g of maleic anhydride; 
were introduced simultaneously over the course of 20 minutes by means of 
two dropping funnels. 
The reaction was exothermic and gave the immediate formation of a yellowish 
suspension. 
When the additions were complete, each funnel was rinsed with acetone (10 
cc), the contents of each of which were then added to the reaction mass, 
still maintained under stirring. 
The dropping funnel which previously contained the maleic anhydride was 
charged with 53.0 g of acetic anhydride and the other funnel was charged 
with 12.2 g of triethylamine. 
These two compounds were then introduced into the reactor over 5 minutes 
and an aqueous solution (0.8 cc) containing 0.0528 mole of nickel acetate 
per 100 cc of solution was then added. 
The reaction mixture was maintained at the reflux temperature, under 
stirring, for 2 hours, 30 minutes. The temperature was then decreased to 
20.degree. C. 
The reaction mixture was precipitated in distilled water at 10.degree. C. 
(500 cc). The viscous, very dark oil collected was washed with a pH 7 
phosphate buffer (250 cc), then with distilled water (2.times.500 cc). The 
product obtained by drying under reduced pressure (30 Pa) for 15 hours at 
30.degree. C. was cooled in an acetone+solid carbon dioxide mixture; 78 g 
of a beige-colored solid having an m.p. of 39.degree. C. were thus 
obtained. 
The NMR spectrum corresponded to the structure of 
N-(3-methallyloxyphenyl)maleimide. 
EXAMPLE 6 
Preparation of N-(2-methallyloxyphenyl)maleimide 
This compound was prepared from 2-methallyloxyaniline. 
(6.1) 2-methallyloxyaniline: 
The starting material was ortho-methallyloxyacetamidobenzene, which was 
obtained under the same conditions as those described in Example 4, 
paragraph (4.1), for para-methallyloxyacetamidobenzene. 
Into a glass reactor equipped with a central stirrer, a thermometer and an 
ascending coolant; 
(i) 205 g of ortho-methallyloxyacetamidobenzene; and 
(ii) 5N ethanolic sodium hydroxide (400 ml); were introduced. After 
homogenization: 
13.6 g of imidazole, which was 20% (in moles) were added. 
The reaction mixture was maintained at the reflux temperature, under 
stirring, for 3 hours. 
The reaction mixture was cooled to 20.degree. C. 
The ethanol was removed under reduced pressure (about 70 Pa). 
Ethyl acetate (250 cc) was added to the reaction mass and the mixture was 
washed with distilled water (2.times.250 cc) until the washings attained a 
pH of 7. 
The ethyl acetate was removed from the organic phase under reduced pressure 
(about 70 Pa) and 168.10 g of crude product were obtained. 
136.10 g of the purified product were obtained by distillation at 
81.degree. C. at 0.05 mm Hg. 
The NMR spectrum corresponded to the structure of 2-methallyloxyaniline. 
(6.2) N-(2-methallyloxyphenyl)maleimide: 
Into a glass reactor equipped with a central stirrer, a thermometer and an 
ascending coolant maintained at 50.degree. C., under stirring, and in 
which a slow stream of nitrogen was circulated: 
(i) an acetone solution (105 cc) containing 65.2 g of 
2-methallyloxyaniline; and 
(ii) an acetone solution (105 cc) containing 45.0 g of maleic anhydride; 
were simultaneously introduced, over the course of 20 minutes, by means of 
2 dropping funnels. 
The reaction was exothermic and gave the immediate formation of a yellowish 
suspension. 
When the additions were complete, each funnel was rinsed with acetone (10 
cc), the contents of each of which were then added to the reaction mass, 
still maintained under stirring. 
The dropping funnel which previously contained the maleic anhydride was 
charged with 53.0 g of acetic anhydride and the other funnel was charged 
with 12.2 g of triethylamine. 
These two compounds were then introduced into the reactor over the course 
of 5 minutes and an aqueous solution (0.8 cc) containing 0.0528 mole of 
nickel acetate per 100 cc of solution was then added. 
The reaction mixture was maintained at the reflux temperature, under 
stirring, for 2 hours, 30 minutes. The temperature was then decreased to 
20.degree. C. 
The reaction mixture was precipitated in iced distilled water (500 cc) 
under vigorous stirring. The chestnut-colored precipitate was filtered, 
washed again with cooled distilled water, and dried for 15 hours at 
40.degree. C. under reduced pressure (30 Pa), and 70.0 g of a 
beige-colored precipitate having an m.p. of 96.degree. C. were obtained. 
The NMR spectrum corresponded to the structures of 
N-(2-methallyloxyphenyl)maleimide. 
EXAMPLE 7 
An apparatus which consisted of a glass reactor equipped with a central 
stirrer and a degassing tubulus connected to a vacuum pump through cold 
traps (acetone+solid carbon dioxide mixture) was used. 
The reactor containing 17.78 g of N-(3-allyloxyphenyl)maleimide was placed 
in an oil bath heated to 150.degree. C. After 3 minutes of heating, 60.44 
g of N,N'-4,4'-diphenylmethane-bis-maleimide were charged therein, over 
the course of 3 minutes, under stirring. After 2 minutes, the reaction 
mass was degassed under reduced pressure (1330 Pa) for 10 minutes at 
150.degree. C. The reaction mass was then clear and it cooled to 
130.degree. C. in 4 minutes. 
Atmospheric pressure was re-established in the reactor and a solution based 
on 0.09 g of imidazole and 1.69 g of triallyl isocyanurate was introduced. 
The mixture was stirred briefly, while maintaining the temperature at 
130.degree. C.; it was then degassed again under reduced pressure (1330 
Pa) for 3 minutes. 
Atmospheric pressure was re-established in the reactor and the resin 
contained therein was then cast in a mold which was pre-heated to 
120.degree. C. and made of two rectangular chromium-plated plates which 
were separated by a 4 mm thick air gap. 
The crosslinking of the resin contained in the mold was carried out at 
atmospheric pressure in an oven heated according to the thermal cycle 
below: 
(a) temperature rise from 120.degree. C. to 150.degree. C. in 1 hour; 
(b) maintenance at 150.degree. C. for 1 hour; 
(c) temperature rise from 150.degree. C. to 200.degree. C. in 40 minutes; 
(d) maintenance at 200.degree. C. for 2 hours; 
(e) temperature rise from 200.degree. C. to 250.degree. C. in 40 minutes; 
(f) maintenance at 250.degree. C. for 16 hours; and 
(g) cooling to room temperature in 1 hour. 
After stripping, a plate was obtained from which test pieces of 
30.times.7.times.4 mm size were cut and used for measuring the initial 
flexural characteristics (strength and modulus): 
Flexural strength: 
at 23.degree. C.: 139 MPa 
at 250.degree. C.: 73.5 MPa 
Flexural modulus: 
at 23.degree. C.: 3387 MPa 
at 250.degree. C.: 2762 MPa 
EXAMPLE 8 
An apparatus which consisted of a glass reactor, equipped with a central 
stirrer and a degassing tubulus connected to a vacuum pump through cold 
traps (a solid carbon dioxide+acetone mixture) was used. 
The reactor was immersed in an oil bath heated to 160.degree. C. The 
reactor was charged with: 
(i) 90.25 g of N,N'-4,4'-diphenylmethane-bismaleimide; 
(ii) 19.25 g of N-(4-allyloxyphenyl)maleimide; and 
(iii) 37.50 g of diphenylsilanediol over the course of 3 minutes, under 
stirring. 
This molten and homogeneous mixture was stirred for 26 minutes. The 
reaction mass was cooled to 120.degree. C. in 10 minutes and degassed 
under reduced pressure (660 Pa) for 4 minutes. 
Atmospheric pressure was then re-established in the reactor and 2.85 g of 
triallyl isocyanurate containing 0.15 g of imidazole were introduced. 
The mixture was stirred for 1 minute, while maintaining the temperature at 
120.degree. C.; it was then degassed again under reduced pressure (400 Pa) 
for 3 minutes. 
The reaction mass was stirred for an additional 5 minutes at 120.degree. C. 
under atmospheric pressure and then cast in a mold which was pre-heated to 
110.degree. C. and which consisted of two rectangular chromium-plated 
plates separated by a 4 mm-thick air gap. 
On another fraction of the composition, changes over time in dynamic 
viscosity at 90.degree. C. (determined with a rotary bob viscometer) and 
its gel time at 160.degree. C. were determined. 
The polymerization of the resin contained in the mold was carried out at 
atmospheric pressure in an oven heated according to the following thermal 
cycle: 
(a) temperature rise from 110.degree. C. to 150.degree. C. in 1 hour; 
(b) maintenance at 150.degree. C. for 1 hour; 
(c) temperature rise from 150.degree. C. to 200.degree. C. in 1 hour; and 
(d) maintenance at 200.degree. C. for 1 hour. 
At the end of this cycle, the resin was polymerized. 
It was reheated (still in the mold) for 15 h, 30 min, in another oven at 
250.degree. C. It was permitted to cool to room temperature. 
After stripping, a pale ochre-colored plate with no surface defects was 
obtained. 
Test pieces of 30.times.7.times.4 mm size were cut from this plate and used 
for the determination of flexural characteristics (strength and modulus) 
before aging (initial values) and after 1000 hours at 250.degree. C. in 
air. 
The weight loss observed after this period of thermal aging was also 
determined on these test pieces. 
Finally, the temperature at which the material began to decompose was 
determined by thermogravimetry at 5.degree. C./minute in air using a test 
piece which was ground to a powder of particle size .ltoreq.100 .mu.m. 
(1) The characteristics measured on the unpolymerized resin were as 
follows: 
Dynamic viscosity at 90.degree. C.: 
time 0 :5.28 Pa.times.s 
after 1 hr at 90.degree. C.: 12.4 Pa.times.s after 2 hr at 90.degree. C.: 
28.8 Pa.times.s 
Gel time at 160.degree. C.: 10.4 minutes. 
(2) Characteristics of the polymerized resin: 
Temperature at beginning of decomposition: 344.degree. C. 
Flexural strength and flexural modulus: 
______________________________________ 
initial after 1000 hr at 250.degree. C. 
at 23.degree. C. 
at 250.degree. C. 
at 23.degree. C. 
at 250.degree. C. 
______________________________________ 
Flexural strength (in MPa): 
110 49 91 48 
Flexural modulus (in MPa): 
1950 1190 2700 1700 
______________________________________ 
Weight loss after 1000 hr at 250.degree. C. in air: 4.58% 
No cracking of the test pieces thus aged. 
EXAMPLE 9 
Example 8 was repeated, substituting N-(4-allyloxyphenyl) maleimide with 
N-(3-allyloxyphenyl) maleimide. 
(1) Characteristics of the unpolymerized resin: 
lnitial viscosity at 90.degree. .C: 0.54 Pa.times.s 
Gel time at 160.degree. C.: 20.9 minutes. 
(2) Characteristics of the polymerized resin: 
Temperature at beginning of decomposition: 354.degree. C. 
Flexural strength and flexural modulus: 
______________________________________ 
initial after 1000 hr at 250.degree. C. 
at 23.degree. C. 
at 250.degree. C. 
at 23.degree. C. 
at 250.degree. C. 
______________________________________ 
Flexural strength (in MPa): 
100 47 106 56 
Flexural modulus (in MPa): 
2000 1300 2500 1500 
______________________________________ 
Weight loss after 1000 hr at 250.degree. C. in air: 5.4% 
EXAMPLE 10 
The procedure of Example 8 was repeated, using the following charges: 
(i) 85.0 g of N,N'-4,4'-diphenylmethane-bismaleimide; 
(ii) 25.0 g of N-(3-allyloxyphenyl)maleimide; and 
(iii) 12.5 g of diphenylsilanediol. 
The molten mixture was stirred for 26 minutes. 
The reaction mass was cooled to 120.degree. C. over 10 minutes and degassed 
at 400 Pa for 4 minutes. 
Atmospheric pressure has then re-established in the reactor and 2.375 g of 
triallyl isocyanurate, containing 0.125 g of imidazole, were introduced. 
The mixture was stirred for 4 minutes at 135.degree. C. and was then 
degassed again for 12 minutes at 930 Pa. 
The amber-colored, homogeneous reaction mass was cast in the pre-heated 
mold described in Example 8 and polymerized as indicated in Example 8. 
(1) Characteristics of the unpolymerized resin: 
Initial viscosity at 90.degree. C.: 0.4 Pa.times.s 
Gel time at 160.degree. C.: 34 minutes 
(2) Characteristics of the polymerized resin: 
Temperature at beginning of decomposition: 358.degree. C. 
Flexural strength and flexural modulus: 
__________________________________________________________________________ 
Flexural strength (in MPa) 
Flexural modulus (in MPa) 
after 1000 hr after 1000 hr 
initial at 250.degree. C. 
initial at 250.degree. C. 
at 23.degree. C. 
at 250.degree. C. 
at 23.degree. C. 
at 250.degree. C. 
at 23.degree. C. 
at 250.degree. C. 
at 23.degree. C. 
at 250.degree. C. 
__________________________________________________________________________ 
138 76 126 59 3000 1900 3100 2600 
__________________________________________________________________________ 
Weight loss after 1000 hr at 250.degree. C. in air: 3.85 
EXAMPLE 11 
The procedure of Example 8 was repeated, using the various reagents listed 
below: 
(i) 90.0 g of N,N'-4,4'-diphenylmethane-bismaleimide; 
(ii) 12.0 g of N,N'-1,3-(4-methylphenylene)-bismaleimide; 
(iii) 15.0 g of diphenylsilanediol; 
(iv) 30.0 g of N-(3-allyloxyphenyl)maleimide; 
(v) 2.85 g of triallyl isocyanurate; and 
(vi) 0.15 g of imidazole. 
(1) Characteristics of the unpolymerized resin: 
Initial dynamic viscosity at 90.degree. C.: 0.82 Pa.times.s 
Gel time at 160.degree. C.: 30 minutes 
(2) Characteristics of the polymerized resin: 
Flexural strength and flexural modulus: 
__________________________________________________________________________ 
Flexural strength (in MPa) 
Flexural modulus (in MPa) 
after 1000 hr after 1000 hr 
initial at 250.degree. C. 
initial at 250.degree. C. 
at 23.degree. C. 
at 250.degree. C. 
at 23.degree. C. 
at 250.degree. C. 
at 23.degree. C. 
at 250.degree. C. 
at 23.degree. C. 
at 250.degree. C. 
__________________________________________________________________________ 
136 74 135 49 3000 2100 3000 2300 
__________________________________________________________________________ 
Weight loss after 1000 hr at 250.degree. C. in air: 3.68% 
EXAMPLE 12 
The apparatus described in Example 8 was charged with 18.78 g of 
N-(3-allyloxyphenyl)maleimide. 
The reactor was immersed in an oil bath heated to 160.degree. C. and 38.32 
g of N,N'-4,4'-diphenylmethane-bis-maleimide and 5.63 g of 
diphenylsilanediol were introduced, under stirring. 
After 8 minutes, the mixture was molten and homogeneous. 
The mixture was stirred for an additional 20 minutes at 160.degree. C. and 
was then cooled to 120.degree. C. 
A degassing was carried out at a pressure of 400 Pa for 4 minutes. 
After returning to atmospheric pressure, a mixture of: 
(i) 0.036 g of imidazole; 
(ii) 1.80 g of N,N',N"-tris(hydroxyethyl)hexahydrotriazine; and 
(iii) 2.94 g of diallyl phthalate; was added. 
Degassing was carried out again at 1300 Pa for 4 minutes at 120.degree. C. 
A portion of the composition was cast in the mold described in Example 3 at 
110.degree. C. The resin contained in the mold was polymerized according 
to the thermal cycle indicated in Example 3. 
(1) Characteristics of the unpolymerized resin: 
Initial dynamic viscosity at 90.degree. C.: 2.57 Pa.times.s 
Dynamic viscosity after 2 hr at 90.degree. C.: 4.54 Pa.times.s 
(2) Characteristics of the polymerized resin: 
Initial flexural strength at 23.degree. C.: 137 MPa 
Initial flexural strength at 250.degree. C.: 53 MPa 
Initial flexural modulus at 23.degree. C.: 2700 MPa 
Initial flexural modulus at 250.degree. C.: 1200 MPa 
EXAMPLE 13 
Example 10 was repeated, substituting N-(3-allyloxyphenyl)maleimide with 
N-(2-allyloxyphenyl)maleimide. 
The amounts of the different reagents used were as follows: 
(i) 40.8 g of N,N'-4,4'-diphenylmethane-bismaleimide; 
(ii) 12.0 g of N-(2-allyloxyphenyl)maleimide; 
(iii) 6.0 g of diphenylsilanediol; 
(iv) 1.14 g of triallyl isocyanurate; and 
(v) 0.06 g of imidazole. 
The composition obtained before polymerization was clear. 
The polymerization in the mold described in Example 8 was carried out 
according to the thermal cycle indicated for the previous examples. 
Characteristics of the polymerized resin: 
Initial flexural strength at 23.degree. C.: 162 MPa 
Initial flexural strength at 250.degree. C.: 84 MPa 
Initial flexural modulus at 23.degree. C.: 3100 MPa 
Initial flexural modulus at 250.degree. C.: 2000 MPa 
EXAMPLE 14 
An apparatus which consisted of a glass reactor, equipped with a central 
stirrer and a degassing tubulus connected to a vacuum pump through cold 
traps (a solid carbon dioxide+acetone mixture) was used. 
The reactor was immersed in an oil bath heated to 160.degree. C. The 
reactor was charged with: 
(i) 67.2 g of N,N'-4,4'-diphenylmethane-bismaleimide; 
(ii) 20.98 g of N-(4-methallyloxyphenyl)maleimide; and 
(iii) 9.82 g of diphenylsilanediol; over the course of 3 minutes, under 
stirring. 
This molten and homogeneous mixture was stirred for 26 minutes. The 
reaction mass was cooled to 120.degree. C. over 10 minutes and degassed 
under reduced pressure (660 Pa) for 4 minutes. 
Atmospheric pressure was then re-established in the reactor and 2.0 g of 
triallyl isocyanurate, containing 0.10 g of imidazole, were introduced. 
The mixture was stirred for 1 minute, while maintaining the temperature at 
120.degree. C.; it was then degassed again under reduced pressure (400 Pa) 
for 3 minutes. 
The reaction mass was stirred for an additional 5 minutes at 120.degree. C. 
at atmospheric pressure and then cast in a mold which was pre-heated to 
110.degree. C. and was made of two rectangular chromium-plated plates 
separated by a 4 mm-thick air gap. 
On another fraction of the composition: changes with time in the dynamic 
viscosity at 90.degree. C. (determined using a rotary bob viscometer) and 
its gel time at 160.degree. C. were determined. 
The polymerization of the resin contained in the mold was carried out at 
atmospheric pressure, in an oven heated according to the thermal cycle 
below: 
(a) temperature rise from 100.degree. C. to 150.degree. C. in 1 hour; 
(b) maintenance at 150.degree. C. for 1 hour; 
(c) temperature rise from 150.degree. C. to 200.degree. C. in 1 hour; 
(d) maintenance at 200.degree. C. for 1 hour. 
At the end of the cycle, the resin was polymerized. 
It was reheated (still in the mold) for 15 hr, 30 min, in another oven at 
250.degree. C. It was permitted to cool to room temperature. After 
stripping, a pale ochre-colored plate with no surface defects was 
obtained. 
Test pieces of 30.times.7.times.4 mm size were cut from this plate and used 
for the determination of flexural characteristics (strength and modulus). 
Finally, the temperature at which the material began to decompose was 
determined by thermogravimetry at 5.degree. C./minute in air, using a test 
piece which was ground into a powder of particle size &lt;100 .mu.m. 
(1) Characteristics of the unpolymerized resin: 
Dynamic viscosity at 90.degree. C.: time 0 226 Pa.times.s 
Dynamic viscosity after 1 hr at 90.degree. C.: 386 Pa.times.s 
Gel time at 160.degree. C.: 13.8 minutes 
(2) Characteristics of the polymerized resin: 
Temperature at beginning of decomposition : 360.degree. C. 
Flexural strength and flexural modulus: 
Initial flexural strength at 23.degree. C.: 113 MPa 
Initial flexural strength at 250.degree. C.: 72 MPa 
Initial flexural modulus at 23.degree. C.: 2470 MPa 
Initial flexural modulus at 250.degree. C.: 1820 MPa 
EXAMPLE 15 
Example 14 was repeated, substituting N-(4-methallyloxyphenyl)maleimide 
with N-(3-methallyloxyphenyl)maleimide. 
After stripping, a pale ochre-colored plate was obtained. 
(1) Characteristics of the unpolymerized resin: 
Dynamic viscosity at 90.degree. C.: time 0: 7.9 Pa.times.s 
Gel time at 160.degree. C.: 23.4 minutes 
(2) Characteristics of the polymerized resin: 
Temperature at beginning of decomposition : 360.degree. C. 
Flexural strength and flexural modulus: 
Initial flexural strength at 23.degree. C.: 122 MPa 
Initial flexural strength at 250.degree. C.: 67 MPa 
Initial flexural modulus at 23.degree. C.: 2400 MPa 
Initial flexural modulus at 250.degree. C.: 1890 MPa 
EXAMPLE 16 
Example 14 was repeated, substituting N-(4-methallyloxyphenyl)maleimide 
with N-(2-methallyloxyphenyl)maleimide. 
After stripping, a dark red, transparent plate was obtained. 
(1) Characteristics of the unpolymerized resin: 
Dynamic viscosity at 90.degree. C.: time 0 8.2 Pa.times.s 
Gel time at 160.degree. C.: 19.5 minutes 
(2) Characteristics of the polymerized resin: 
Temperature at beginning of decomposition: 363.degree. C. 
Flexural strength and flexural modulus: 
Initial flexural strength at 23.degree. C.: 1400 MPa 
Initial flexural strength at 250.degree. C.: 67 MPa 
Initial flexural modulus at 23.degree. C.: 2530 MPa 
Initial flexural modulus at 250.degree. C.: 1800 MPa 
While the invention has been described in terms of various preferred 
embodiments, the skilled artisan will appreciate that various 
modifications, substitutions, omissions, and changes may be made without 
departing from the spirit thereof. Accordingly, it is intended that the 
scope of the present invention be limited solely by the scope of the 
following claims, including equivalents thereof.