CA1315463C - Process for the production of high molecular weight polyamide-imide resin - Google Patents
Process for the production of high molecular weight polyamide-imide resinInfo
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- CA1315463C CA1315463C CA000590859A CA590859A CA1315463C CA 1315463 C CA1315463 C CA 1315463C CA 000590859 A CA000590859 A CA 000590859A CA 590859 A CA590859 A CA 590859A CA 1315463 C CA1315463 C CA 1315463C
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Abstract
ABSTRACT OF THE DISCLOSURE
High molecular weight polyamide-imides having a reduced viscosity of 0.3 dl/g or above and exhibiting excellent heat resistance and melt flowability is produced with good economic efficiency by a process, which process comprises the two reaction stages:
(a) a first reaction stage which comprises reacting (I) a trimellitic acid derivative and (II) an aromatic diamine in the presence of a polar solvent in the presence of a first dehydration catalyst until a polyamide-imide resin having a reduced viscosity of 0.2 to 0.5 dl/g as measured at a concentration of 0.5 g/dl in dimethylformamide at 30°C is produced; and (b) a second reaction stage which comprises adding a phosphorous ester as a second dehydration catalyst to the reaction mixture resulting from the first reaction stage and further reacting the reaction mixture until a high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above as measured at a concentration of 0.5 g/dl in dimethylformamide at 30 °C is produced.
High molecular weight polyamide-imides having a reduced viscosity of 0.3 dl/g or above and exhibiting excellent heat resistance and melt flowability is produced with good economic efficiency by a process, which process comprises the two reaction stages:
(a) a first reaction stage which comprises reacting (I) a trimellitic acid derivative and (II) an aromatic diamine in the presence of a polar solvent in the presence of a first dehydration catalyst until a polyamide-imide resin having a reduced viscosity of 0.2 to 0.5 dl/g as measured at a concentration of 0.5 g/dl in dimethylformamide at 30°C is produced; and (b) a second reaction stage which comprises adding a phosphorous ester as a second dehydration catalyst to the reaction mixture resulting from the first reaction stage and further reacting the reaction mixture until a high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above as measured at a concentration of 0.5 g/dl in dimethylformamide at 30 °C is produced.
Description
PROCESS FOR THE PRODUCTION OF HIGH MOLECULAR WEIGHT
POLYAMIDE-IMIDE RESIN
BACKGROUND OF THE INVENTION
(a) Field of the Invention The present invention relates to processes for producing polyamide-imide resins and, more particularly, it relates to economical processes for producing high molecular weight polyamide-im.ide resins exhibiting excellent heat resistance and melt flowability.
(b) Description o~ the Related Art As methods of producing polyamide-imides, :; a solution polymerization method with aromatic : : dilsocyanates (see Japanese Patent Application Publication No. 48-19274), a precipitation polymerization method with aromatic diisocyanates (see Japanese Patent Application Publicatlon No. 54-44719), a solution polymerization method with pyromellitic acid chlorides (see Japanese Patent ~ Applicatîon Publication No. 42-15637), and a solution : polymerization method with aromatic diamines (Japanese Patent Application Publication No. 49-4077) are Xnown. In the oase o~ the solution polymerization method with aromatic diisocyanates, undesirable side reactions tend to occur from the start of polymerization causing a dif~iculty in production of linPar polymers having high molecular weight.
The polymers produced by the method are therefore too poor in melt flowability to be suitable for the use of molding materials or the liXe.
Precipitation polymerization method with aromatic diisocyanates has problems in safety in working environment and cost since reaction is carried out using highly poisonous nitro compounds or expensive sulfolane type solvents. Further, the method, due to it's difficulty in controlling molecular weight, has difficulty in quality control of the product. Furthermore, the method tends to induce side reactions like the above-described solution I5 polymerization method with aromatic diisocyanates, and there~ore the produced polymers are also inferior in melt flowability. A solution polymerization method with pyromellitic acid chlorides is disadvantageous in cost since it needs a step for purifying the by-produced halogen compounds. Further, in case of producing modified polymers, the method has such a disadvantage as the restriction in materials to be used.
On the other hand, a solution polymerization method with aromatic diamines is free from these problems and is a useful method well-balanced in cost and melt flowability c~t~
` 1315~63 l and heat resistance of the product polymers. The method i5 practically carried out using a dehydration catalyst, ror example, phosphoric acid type catalysts such a~ phosphoric acid and polyphosphoric acid, borlc acid type catalysts such as boric acid and boric anhydride, and phosphorous triesters such as triphenyl phosphite. It is known that catalytic effects of these catalysts substantially dif-fer according to the kind thereo~.
That is, wh:Lle a single catalyst system o-f phosphoric acld, polyphosphoric acid or boric acid can exhibit sufficient catalytic effect with a small amount, it however needs a long time reaction at a high temperature of 200C or more. Therefore, even if N-methylpYrrolidone (boiling point: 202C ), which is a high boiling point solvent, is used as the solvent for synthesis, there will ~requently occur un~esirable phenomenon that the generating resins havi~g high molecular weight and high viscosity are -baked or stuck to the surface of reactor wall irl the course of the hi~h temperature and long time synthetic process.
While a slngle catalyst system of phosphorous tries$ers can achieve high molecular weight polymerization in a reaction at a relatively low temperature of 190C or less, it lS
required in an amount equivalent to the amount of the condensation-reactive groups of the acid component or amine component, and the use of a large quantity of expensive 13t5463 catalyst causes problems of cost and difficulty in controlling molecular weight.
SUMMARY OF THE INVENTION
An object of the present invention is to solve the problems of the conventional methods descr-ibed above and to provide an economical process for producing high molecular weight polyamide-imide resin having excellent heat resistance and melt flowability.
That is, the pre~ent invention provides a process for producing high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above by reacting a trimellitic acid derivative (I~ selected from the group consisting of trimellitic acid anhydride and an ester of trimellitic acid or trimellitic acid anhydride with an alcohol and an aromatic diamine (II), in the presence of a polar solvent and dehydration catalyst, which process comprises the two reaction stages: (a) a ~irst reaction stage which comprises reacting the trimellitic acid deriYative (I) and the aromatic diamine tII) in the presence of a polar solvent in the presence of a first dehydration ca~alyst selected from the group consisting of boric acld, boric anhydride, phosphoric aoidj pyrophosphoric acids, metaphosphoric acids, ethylmetaphosphoric acid, polyphospho~ic acid, phosphorus pentoxide, and phosphoric pentachloride at a temperature ranging from about 195C to about 205C until a polyamide-imide resin having a reduced d~
viscosity of 0.2 to 0.5 dl/g as measured at a concentration of 0.5 g/dl in di~ethylformamide at 30C is produced; and ~b) a second reaction stage which comprises adding a phosphorus triester as a second dehydration catalyst to the reaction mixture resulting from the first reaction stage and further reacting the reaction mixture at a temperature ranging from about 180C to about 190C until a high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above as measured at a concentration of 0.5 g/dl in dimethylformamide at 30C is produced; the first dehydration catalyst being used in an amount of 0.5 to 20% by weight on the basis of the total of the trimellitic acid derivative (I) and the aromatic diamine (II), and the phosphorus triester as a second dehydration catalyst being used in an amount of 0.1 to 50% by weight on the basis of the total of the trimellitic acid derivative (I) and the aromatic diamine (II).
Further, the present invention provides a process for producing high molecular weight polyamide imide resin having a reduced viscosity of 0.3 dl/g or above by reacting a trimellitic acid deri~ative (I) selected from the group consisting of trimellitic acid anhydride and an ester of trimellitic acid or trimellitic acid anhydride with an alcohol and an aromatic diamine (II), and one or more compounds (III) selected from the group consisting of (A) dicarboxylic acids and (B) lactams, in the presence of a polar solvent and dehydration catalyst, which process comprises the two reaction stages: (a) a first reaction stage which comprises reacting the trimellitic acid derivative (I) and the aromatic diamine (II), and one or more compounds (III) selected from the group consisting of (A3 dicarboxylic acids and (B) lactams, in the presence of a polar solvent in the presence of a first dehydration catalyst selected from the group consisting of boric acid, boric anhydride, phosphoric acid, pyrophosphoric acids, metaphosphoric acids, ethylmetaphosphoric acid, polyphosphoric acid, phosphorus pentoxide, and phosphoric pentachloride at a temperature ranging from about 195C to about 205C until a polyamide-imide resin having a reduced viscosity of 0.2 to 0.5 dl/g as measured at a concentration of 0.5 g/dl in dimethylformamide at 30C is produced; and (b) a second reaction stage which comprises adding a phosphorus triester as a second dehydration catalyst to the reaction mixture resulting from the first reaction stage and further reacting the reaction mixture at a temperature ranging from about ~80C to about 190-C until a high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above as measured at a concentration of 0.5 g/dl in dimethylformamide at 30C is produced; the first dehydration catalyst being used in an amount of 0~5 to 20% by weight on the basls of the total of the trimellitic acid derivative (I) and the aromatic diamine (II), and the one or more compounds (III) and the phosphorus triester as a second dehydration catalyst being used in an amount of 0.1 to 50% by weight on the basis of the total of the trimellitic acid derivative (I) : the aromatic diamine (II) and the one or more compounds (III).
.,.~, ~, ~'' - 6a -BRIEF DESCRIPTION OF DRAWING
Figure 1 shows the relationship between reaction time and reduced viscosity in Example 2 and Comparative Examples 1 and 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Some illustrative examples of (I) trimellitic acid derivatives to be used in the present invention include trimellitic acid anhydride and esters of trimellitic acid or trimellitic acid anhydride with an alcohol. Typical examples of the esters of trimellitic acid or trimellitic acid anhydride with an alcohol are monomethylesters o~ trimellitic acid or trimellitic acid anhydride. The pre~erred trimellitic acid derivative is trimellitic acid anhydride.
Some illustrative examples o~ (IIj aromatic ~ 131S463 1 diamines to be used in the pre.sent invention include m-phenylenediamine, p-phenylenediamine, 4,4' -diaminodiphenylpropane, 4,4' -diaminodiphenylmethane, 4,4' -diaminodiphenyl sulfide, 4,4' -diaminodiphenyl sulfone, 4,4' -diaminodiphenyl ether, 1,5-diaminonaphthalene, 3,3' -diaminobiphenyl, 3,3' -dimethoxybenzidine, 1,3-diamino-4-isopropylbenzene, xylylenediamine, 4,4~ -diaminoterphenyls, 4,4"' -diaminoquarterphenyl, 1,4-bis(p-aminophenoxy)benzene, 4,4' -bis(p-aminophenoxy)diphenyl sulfone~ ~
4,4' -bis(p-aminophenoxy)biphenyl, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bisl4-(4-aminophenoxy)phenyl~hexafluoropropane, 4,4' -diaminoben~ophenone, benzidine-2,3,5,6-tetramethyl-p-phenylenediamine, diaminotoluenes, tetrafluorophenylened1amines, and diaminooctafluorobiphenyls. These compounds may be used indlvidually or as a mixture thereof. In consideration o-f 20 ~ heat resistance and economical e~ficiency, the preferred aromatic diamines are 4~4' -dlaminodiphenylmethane, 4,4' -diaminodiphenyl ether,~p-phenylenediamine, and m-phenylenediamine.
The preferred polar solvents to be used in the present invention are those being capable of easily 1 dissolving the produced polyamide-imide resins and having a boiling point o~ 180C or above. Some illustrative examples o~ the preferred polar solven1;s 1nC1Ude N-methylpyrrolidone, N-ethylpyrrolidone, N-butylpyrrolidone, phenol, cresols, xylenols, r -butyrolactone, and sulfolane.
Among these, the particularly pre~erred is N-methylpyrrolidone.
Some illustrative examples of the first dehydration catalysts to be used in the present invention in the first reaction stage include boric acid and boric acid derivatives such as boric anhydride; pentavalent phosphorus compounds, for example, phosphoric acid, pyrophosphorlc acid, metaphosphoric acids such as trimetaphosphoric acid, ethylmetaphosphorie acid, polyphosphoric acids such as tetrapolyphosphoric acid, :
phosphorus pentoxide, and phosphorlc pentachloride. The preferred are phosphoric acid, polyphosphoric acids, boric acid, and boric anhydride, and the particularly preferred ls phosphoric acid.
The second dehydration catalysts to be used in the present invention in the second re~ction stage are phosphorous triesters~represented by the formula (R0)3P, wherein R is an aliphatic or aromatic su~stituent such as methyl, ethyl, isopropyl, butyl, 2-ethylhexyl, isooctyl, decyl, lauryl, phenyl, methylphenyl, ethylphenyl, 1 butylphenyl, octadecylphenyl, nonylphen~l, diphenylnonyl, biphen~l~l, cyclohexyl, and indenyl; and the preferred is triphanyl phosphite.
In the present invention, ~I~ trimellitic acid derivative and (II) arosnatic diamine are used preferably in an amount equimolar with each other, and the particularly preferable molar ratio, (II)/~I), is from 0.98 to 1.02.
In the present invention, one or more compounds (III) selected from the group consisting of (A) dicarboxylic acids and (B) lactams in addition to the (I) trimellitic acid derivative and (II) aro~atic diamine mentioned above may be used as materials at need.
Some illustrative examples of the (A) ~
dicarbo~ylic acids~which may be~used in the present inverlt10n include succinic aeid, adipic acid, sebacic acid, dodecanedicarboxylic acid, isophthalic acid, and terephthalic acid. In consideration of heat resistance and solubility o-~ the product resins, isophthalic acid is prefe~ably used.
In case of using the (A) dicarboxylic acids, it is desirable, in conslderation of heat resistance and flowability at the time of moldlng process, to use (A) as a part of acid component in an amount of 0.05 to O.S0 mol, preferably 0.1 to Q.3 mol per 1 mol of the (II) aromatic diamine.
1 31 ~463 1 Some illustrative examples of the (B) lactams which may be used in the present invention include lactams represented by the following general formu:La:
NH ~ C0 ~ ( C:~I2 ) r~/
wherein, n is an integer of from 2 to 20, and the preferred is ~ -caprolactam.
From the viewpoint of heat resistance and flowability at the time of molding process. it is desirable to use (B) in an amount of 0.05 to 0.50 mol, pre~erably 0.05 to 0.30 mol per 1 mol of the (II) aromatic diamine.
According to the present invention, acid component and amine component are reacted firstly in the : : ~ first reaction stage using the first dehydration catalyst until the reduced viscosity of polyamide-imide resin : produced reaches 0.2 to 0.5 dl/g, and the reaction is : further progressed by adding a phosphorous triester as the ; 20 second dehydration catalyst to increase the reduced ~iscosity of the polyamide-imide resin to 0.3 dl~g or above.
If the first reaction stage is concluded before : the reduced vi,scosity reaches 0.2 dl/g, the amount o~ the : : 25 second dehydration catalyst required wiIl be approximatelY
~15463 1 equivalent to the amount of acid component or amine component, causing the sa~e problem as that caused by separate use of the second dehydration catalyst. If the reduced viscosity exceeds 0.5 dl/g, partial gelation or runaway reaction will occur at the time of addition of the second dehydration catalyst, causing a di-friculty in controlling the molecular weight. The reduced viscosity of the polyamide-imide resin obtained in the second reaction stage should be 0.3 dl/g or above. In consideration of heat resistance, mechanical strength or the llke, the preferable reduced viscosity is 0.4 or above.
From the viewpoint of reactivity and facility~of purification, it is preferable to use the first dehydration catalyst of the present invention in an amount of 0.5 to 20 % by weight on the basis of total of the reaction species including (I) and ~II) or~ (I), (II) and (III). The particularly preferable amount is l to 5 % by weight.
From the view point of reactivity and facility of reaction control, it is preferable to use the second dehydration catalyst in an amount of 0.1 to 50 % by weight on the basis of total of the reaction species including (I) and (II) or ~I), (II) and (III). The particularly preferable amount is 3 to 30;X by weight.
In the present invention, the total concentration of the reactants of the polymerization system during the 1~
1 first reaction stage using the ~irst dehydration catalyst is preferably about 50 to 60 % by weight, and that during the second reaction stage using -the second dehydration catalyst is preferably about 30 to 40 % by weight. With regard to the reaction temperature, it is desirable to add the ~irst dehydration catalyst at a temperature in the vicinity of 170C , then carry out polymerization at a temperature in the vicinity o-f 195 to 205C , and conduct the addition o~ the second dehydration catalyst and the reaction in the second reaction stage at a temperature range of about 180 to 190C .
It is desirable to carry out the ~irst reaction stage and second reaction stage in an atmosphere of an inert gas such as nitro~en.
The polyamide-imlde resins obtained by the present invention may be protected with end-group blocking agents at the end of the polymerization reaction. The end-group protection increases the heat stability at the time20 o-~ molding.
The end-group blocking agents which may be used include, ~or example, phthalic anhydride, benzoic acid, acetic anhydride, aniline, n-butylamine, and phenyl isocyanate.
Z5 The polyamide-imide resins obtained by the 1 present invention may be, if desired, further diluted by adding the above-described polar solvents or low boiling point organic solvents, such as chloroform, tetrahydrofuran, diox~ne, toluene, and xylene, to the product solution resulting from the polymerization.
The polyamide-imide resins obtained hy the present invention may be used in solution state or powder state and also may be blended with other kinds o~ polymers, additives, fillers, reinforcing agents, etc., if de.sired.
The polyamide-imide resins obtained by the present invention, at need, may be improved o-f their physical properties extremely by heating them (for example, at 200 to 300~ for 1 to 24 hours) after molding.
According to the present invention, high molecular weight polyamide-imide resins having excellent heat resistance, melt flowability, and economical efficiency can be obtained.
~ :
The polyamlde-imide resins obtained by the present invention are suitable for the use of thermoplastic moldlng materials and are~ also useful as, ~or example, heat resistant materials ~or~heat resistant paints, heat resistant sheet~, heat resistant adhesives, heat resistant la~inating materials, heat resistant sliding materials, heat resistant fibers, heat resistant films, and the like.
In order to more fully and clearly illustrate the ~ ' 1315~63 1 present invention the following examples are set ~orth. It is intended that the examples be considered as illustrative rather than limiting the invention as disclosed and claimed herein.
The following examples also illustrate processes falling outside the scope of the instant invention and are presented for comparative purposes only.
EXAMPLES 1 to 5 and COMPARATIVE EXAMPLES 1 to 5 EX~MPLE 1 Mol ratio g wt. part trimellitic acid anhydride1.00 192 48.7 4,4' -diaminodiphenylmethane1.02 202 51.3 a~ueous phosphoric acid solution 0.02 2.3 0.5 (content of phosphoric acid: 85 %) N-methylpyrrolidone - 394 100 triphenyl phosphite 0.13 40 10 : ~ :
Irlto a four necked flask equipped with a stirrer, a nitrogen introduction tube, and an apparatus for moisture determination were placed the above components except triphenyl phosphlte, and the con~ent was dissolved by raising the temperature slowly to 180C with stirring under introduction of nitrogen gas. Subsequently, the resulting ~ ,~ ,, 1 solution was further heated to 210C and reaction was continued while removing rapidly ~he distilled water out of the reaction syskem and at the same time filling up the distilled N-methylpyrrolidone (first reaction stage). The progress of reaction was watched by measuring~the increase of molecular weight of the polymer with ~PLC (high per~ormanee liquid chromatography) to obtain a polyamide-imide resin having a reduced viscosity o~ U.3 dl~g as measured at a concentration of 0.5 g/dl in dimethylformamide at 30C . Subsequently, the resin concentration was diluted to 35 % by weight by adding N-`methylpyrrolldone and the reactlon temperature was lowered to 180C . Triphenyl phosphite was added in 5 portions over a period of 2 hours and the reactlon was continued (~second~
reaction stage). The end point o* the reaction was determined by measuring the molecular weight with~HPLC.
: ~ :
Thus a polyamide-imide resin~having a reduced viscosity of 0.65 dl/g was Pinally obtained. Nothlng unusual such as scorching o-f resin to the inner wall of the flask or gelation was observed.~
Mol ratio g wt. part trimellitic acid anhydride 1.00 192 48.7 1315~63 1 4,4' -diaminodiphenylmethane 1.02 202 51.3 aqueous phosphoric acid solution 0Ø223.2 5 (content of phosphoric acid: 85 %) N-methylpyrrolidone - 394 100 triphenyl phosphite 0.3.2 98.5 25 The procedure of Example 1 was repeated with the exception that the above components were used. First, first reaction was carried out to obtain a polyamide-imide resin having a reduced viscosity of 0.45 dlig.
Subsequently, second reaction was carried out to obtain a polyamide-imide resin having a -final reduced viscosity of 0.8 dl/g. Nothing unusual such as scorching of resin to the lnner wall oY the flask or gelation was observed.
. :
15 : EXAMPLE 3 :
Mol ratio g wt. part trlmellitic acid anhydride 1.00 192 48.7 4,4' -diaminodiphenylmethane 1.02 202 51.3 aqueous phosphoric acid solutlon 0.32 37.l 8 : ~ (content of phosphoric acid: 85 %) N-methylpyrrolidone - 394 100 : triphenyl phosphite : 0.065 2.0 0.5 The procedure of Exa~mple 1 was repeated with the ~5 exception that the above components were used. F:lrst, t 31 ~463 1 first reaction was carried out to obtaln a polyamide-imide resin having a reduced viscosity Or 0.3 dl/g.
Subsequently, second reaction was carried out to obtain finally a polyamide-imide resin having a reduced viscosity o-f 0.6 dl~g. Nothing unusual such as scorching o~ resin to the inner wall of the flask or gelation was observed.
~ol ratio g wt. part trimellitic acid anhydride 0.90 172.841.7 4,4' -diaminodiphenylmethane 1.02 202.048.8 isophthalic acid 0.10 16.64.0 ~ -caprolactam 0.20 22.65.5 aqueous phosphoric acid solution 0.21 24.3 5.9 (content of phosphoric acid: 85 %) N-methylpyrrolidone - 414 100 triphenyl phosphite 0.33 103,525 The procedure o~ Example 1 was repeated with the exception that the above components were used. First, ~irst reaction was carried out to obtain a polyamide-imide resin having a reduced viscosity of 0.3 dl/g.
Subsequently, second reaction was carried out to obtain a polyamide-imide resin having a reduced viscos~ty of 0.8 ~5 dl/g. Nothing unusual such as scorching of resln to the 13~5~63 1 inner wall of the flask or gelation was observed.
EX~MPLE 5 Mol ratio g wt. part trimellitic acid anhydride 0.85 163.2 ~0.6 4,4' -diaminodiphenylmethane 1.02 202.0 50.3 isophthalic acid 0.15 24.9 6.2 ~ -caprolactam 0.10 11.3 2.8 aqueous phosphoric acid solution 0.024 2.4 0.
: (content of phosphoric acid: 85 ~
N-methylpyrrolidone - 401.4 100 triphenyl phosphite 0.52 1~0.5 40 The procedure of Example 1 was repeated with the ~: 15 exception that the above component~ were used. First, first reaction was carried out to obtain a polyamide-imide : resin having a reduced viscosity of 0.45 dl/g.
Subsequently, second reaction was carried out to obtain a polyamide i~ide resin having a final reduced viscosity of 1.0 dl/g. Nothing unusual such as scorching of resin to the inner wall of the flask or gelation was ob~erved.
: ~ :
:
131~4~3 Mol ratio g wt. part trimellitic acid anhydride l.Q~ 19~ 48.7 4,4' -diaminodiphenylmethane 1.02 202 51.3 N-methylpyrrolidone - 394 100 Into the same type four-necked ~lask as that used in Example 1 were placed the above components and the content was dissolved by raising the temperature slowly to 180C with stirring under introductlon of nitrogen gas.
Subsequently, the resulting solution was ~urther heated to 210C and reaction was progressed, while the distilled~
water was rapidly removed o~ out of the reaction system ; 15 and at the same time the distilled N-~ethylpyrrolidone was filled op (first react~on stage). The progress of reaction was monitered by measuring the increase of molecular weight with HPLC to obtain a polyamide-imide resin having a ~ reduced viacoslty of 0.18 dl/g as measured at a ; ~20 concentration of~ 0.5~ g/dl in dlmethylformamide at 30C .
~ ~ The reac~ion product was a low viscoslty liquid.
:~: : :
1315~63 Mol ratio g wt. part trimellitic acid anhydride 1.00 192 48.7 4 ? 4' -diaminodlphenylmethane1.02 202 51.3 N-methylpyrrolidone - 394 100 aqueous phosphorlc acld solution 0.60 69.5 15 (content o~ phosphoric acid: 85 %) The procedure o~ the reaction stage 1 o~ Example 1 was repeated with the exception that the above components : were used, to obtain a polyamide-imide resin having a reduced v~scosity o~ 0.45 dl/g. However, since a:high temperature and a long reaction tlme (210C - 25 hours) were required -~or the reaction, scorchlng occurred on the bottom of the ~lask.~ :
Mol ratio g :wt. part 20~ trimellitic acld anhydride: 1.00 192 48.7 4,4' -diaminodiphenylmethane 1.02 202 51.3 N-methylpyrrolidone - 394 100 triphenyl phosphite 0.76 236 59.9 The procedure o~ the ~irst reaction stage o~
1 Example 1 was repeated with the exceptlon that the above components were used, to obtain a polyamide-imide resin having a reduced viscosity o-~ 0.18 dl/g. Subsequently, the resin concentration was decreased to 3~ % by wei~ht by adding N-methylpyrrolldone, and th~ reaction temperature was lowered to 180 to 190C . While the reaction was progressed by adding triphenyl phosphite in 5 portions over a period o~ 2 hours, the viscosity o~ varnish was rapidly increased and gelatinized.
Mol ratio g wt. part trimellitic acid anhydride 1.00 19248.7 4,4' -diaminodiphenylmethane 1.02 202 51.3 I
N-methylpyrrolldone - 394 100 aqueous phosphoric acid solution 0.02 0.23 0.06 (content of phosphoric acid: 85 %) triphenyl phosphite 0.76 236 60 The procedure of Example l was repeated with the exception that the above components were used. First, first reaction stage was carrled out to obtaln a polyamide-imide having ~ reduced viscosity of 0.18 dl/g.
Subsequently, triphenyl phosphite was added and reactlon was progressed ~or about 30 mlnu~es (second reaction .
.
1 stage). The reduced viscosity o-~ vanish was increased and the varnish was gelatinized at the end.
Mol ratio g wt. part trimellitic acid anhydridel.OO 192 4~.7 4,4' -dLaminodiphenylmethane1.02 202 51.3 N-methylpyrrolidone - 394 100 aqueous phosphoric acid solution 0.60 69.6 15 (content o~ phosphoric acid: 85 %) triphenyl phosphite 0.0064 1.97 0.05 The procedure of Example 1 was repeated w1th the~
exception that the above componente were used. First, I
1 15 first reaction stage was carrled out to obtain a polyamide-: .
imide resin having a reduced viscos1ty of 0.35 dl/g.
Subsequently, the second stage polymerization was attempted. However, polymerization to a high molecular w~eight polyamide-imide -~ailed to proceed under the reaction ~; 20 condltions, resulting in a solution with a final redueed ylscoslty o-~ 0.38 dl/~.
~ Films were produced from the polyamide-imide -~ resins obtained ln E~amples 1 to 5 and Co~parative E~amples 1 to 5 and glass transition tem~erature was mea ured with a thermomechanical analyzer. The results and the appearance of reaction in the course o-f synthesis were shown in Table 1.
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~ o C:~ o I I o ~o oo I o ~ I
X Z ~ ~1 0 O O
~ o o I I I ~o ~ I o .~ I
~ 2: ~ _ ~4, E C`l C`:l O I I Ln I I Ln LE~
c~ o o ~ I I ~r C~ X C~l ._ ~ O ~
C`~ O I I O I I CO ~ 0 2: o o o cY:)OO a) Ll~ ~0 ~ ~ ~ O ~ O C~ O U~
O ~ O o o o O ~ C~l O a~ C~ CO ~3 0 Ct~
:Z: ~ O O O O O C`~
Q~ C.~ O I I 00 u~ h~ CD ~ O
E Z .~ O O O C`~
.-1 X .
~ O ~ 0 1 1 ~ ~ L~ 00 C`~
~ :Z _ ._ O Q~
: ;Z ~ O I I ~ -4 o ~D ~ O ~ C
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E O ~ ~ ~
~ h 3 ~ h ~ b E ~ ~ ~ .C_) l O h ~_ :~ C h ~ 3 .~ _. : 2) r ~ ~ ~1) h c~
,C~ ~ .. C E ~ Cl. ,1:: ~ O
~C ~ O O :~ C~ ~
E ~ _ O ~ -- ~ O ~ E ~:
.~ al h h :~ ~: h . ~
~ o .~ ~ b ~ o I a~ .c ~ Q ~ ~ Q) _, et' ~4 0 1 0 ~-- ~ ta c: Il) ._ ~
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c ~ ~ v~ e .~ ~ ~ O O b a~
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!S~b ;
t315~63 1 The relationships between reaction time and reduced viscosity in Example 2 and Comparative Examples 1 and 2 are shown in Fi~ure 1.
The reaction appearance shown in the Table 1 was ~udged by examinlng the occurrence of scorching on the flaskls wall or generation o~ gelatinized matter. O
represents absence, and x represents presence.
~ he measuremen-t o~ glass transition temperatures (Tg) of films were conducted using a thermomechanical analyY,er of Perkin Elmer TMS-1.
Measuring conditions tension method temperature raising rate: 10C /min, load: 5 g, sample: 2 mm width, spun: 10 ~n Production o~ ~ilm 25 wt.% varnish was applied over a clean glass plate with an applicator to a thlckness o~ 80 ~ m and was 2~ then heated for 30 minutes with a 250C hot air dryer to obtain a film of about 20 ~ m thlckness.
POLYAMIDE-IMIDE RESIN
BACKGROUND OF THE INVENTION
(a) Field of the Invention The present invention relates to processes for producing polyamide-imide resins and, more particularly, it relates to economical processes for producing high molecular weight polyamide-im.ide resins exhibiting excellent heat resistance and melt flowability.
(b) Description o~ the Related Art As methods of producing polyamide-imides, :; a solution polymerization method with aromatic : : dilsocyanates (see Japanese Patent Application Publication No. 48-19274), a precipitation polymerization method with aromatic diisocyanates (see Japanese Patent Application Publicatlon No. 54-44719), a solution polymerization method with pyromellitic acid chlorides (see Japanese Patent ~ Applicatîon Publication No. 42-15637), and a solution : polymerization method with aromatic diamines (Japanese Patent Application Publication No. 49-4077) are Xnown. In the oase o~ the solution polymerization method with aromatic diisocyanates, undesirable side reactions tend to occur from the start of polymerization causing a dif~iculty in production of linPar polymers having high molecular weight.
The polymers produced by the method are therefore too poor in melt flowability to be suitable for the use of molding materials or the liXe.
Precipitation polymerization method with aromatic diisocyanates has problems in safety in working environment and cost since reaction is carried out using highly poisonous nitro compounds or expensive sulfolane type solvents. Further, the method, due to it's difficulty in controlling molecular weight, has difficulty in quality control of the product. Furthermore, the method tends to induce side reactions like the above-described solution I5 polymerization method with aromatic diisocyanates, and there~ore the produced polymers are also inferior in melt flowability. A solution polymerization method with pyromellitic acid chlorides is disadvantageous in cost since it needs a step for purifying the by-produced halogen compounds. Further, in case of producing modified polymers, the method has such a disadvantage as the restriction in materials to be used.
On the other hand, a solution polymerization method with aromatic diamines is free from these problems and is a useful method well-balanced in cost and melt flowability c~t~
` 1315~63 l and heat resistance of the product polymers. The method i5 practically carried out using a dehydration catalyst, ror example, phosphoric acid type catalysts such a~ phosphoric acid and polyphosphoric acid, borlc acid type catalysts such as boric acid and boric anhydride, and phosphorous triesters such as triphenyl phosphite. It is known that catalytic effects of these catalysts substantially dif-fer according to the kind thereo~.
That is, wh:Lle a single catalyst system o-f phosphoric acld, polyphosphoric acid or boric acid can exhibit sufficient catalytic effect with a small amount, it however needs a long time reaction at a high temperature of 200C or more. Therefore, even if N-methylpYrrolidone (boiling point: 202C ), which is a high boiling point solvent, is used as the solvent for synthesis, there will ~requently occur un~esirable phenomenon that the generating resins havi~g high molecular weight and high viscosity are -baked or stuck to the surface of reactor wall irl the course of the hi~h temperature and long time synthetic process.
While a slngle catalyst system of phosphorous tries$ers can achieve high molecular weight polymerization in a reaction at a relatively low temperature of 190C or less, it lS
required in an amount equivalent to the amount of the condensation-reactive groups of the acid component or amine component, and the use of a large quantity of expensive 13t5463 catalyst causes problems of cost and difficulty in controlling molecular weight.
SUMMARY OF THE INVENTION
An object of the present invention is to solve the problems of the conventional methods descr-ibed above and to provide an economical process for producing high molecular weight polyamide-imide resin having excellent heat resistance and melt flowability.
That is, the pre~ent invention provides a process for producing high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above by reacting a trimellitic acid derivative (I~ selected from the group consisting of trimellitic acid anhydride and an ester of trimellitic acid or trimellitic acid anhydride with an alcohol and an aromatic diamine (II), in the presence of a polar solvent and dehydration catalyst, which process comprises the two reaction stages: (a) a ~irst reaction stage which comprises reacting the trimellitic acid deriYative (I) and the aromatic diamine tII) in the presence of a polar solvent in the presence of a first dehydration ca~alyst selected from the group consisting of boric acld, boric anhydride, phosphoric aoidj pyrophosphoric acids, metaphosphoric acids, ethylmetaphosphoric acid, polyphospho~ic acid, phosphorus pentoxide, and phosphoric pentachloride at a temperature ranging from about 195C to about 205C until a polyamide-imide resin having a reduced d~
viscosity of 0.2 to 0.5 dl/g as measured at a concentration of 0.5 g/dl in di~ethylformamide at 30C is produced; and ~b) a second reaction stage which comprises adding a phosphorus triester as a second dehydration catalyst to the reaction mixture resulting from the first reaction stage and further reacting the reaction mixture at a temperature ranging from about 180C to about 190C until a high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above as measured at a concentration of 0.5 g/dl in dimethylformamide at 30C is produced; the first dehydration catalyst being used in an amount of 0.5 to 20% by weight on the basis of the total of the trimellitic acid derivative (I) and the aromatic diamine (II), and the phosphorus triester as a second dehydration catalyst being used in an amount of 0.1 to 50% by weight on the basis of the total of the trimellitic acid derivative (I) and the aromatic diamine (II).
Further, the present invention provides a process for producing high molecular weight polyamide imide resin having a reduced viscosity of 0.3 dl/g or above by reacting a trimellitic acid deri~ative (I) selected from the group consisting of trimellitic acid anhydride and an ester of trimellitic acid or trimellitic acid anhydride with an alcohol and an aromatic diamine (II), and one or more compounds (III) selected from the group consisting of (A) dicarboxylic acids and (B) lactams, in the presence of a polar solvent and dehydration catalyst, which process comprises the two reaction stages: (a) a first reaction stage which comprises reacting the trimellitic acid derivative (I) and the aromatic diamine (II), and one or more compounds (III) selected from the group consisting of (A3 dicarboxylic acids and (B) lactams, in the presence of a polar solvent in the presence of a first dehydration catalyst selected from the group consisting of boric acid, boric anhydride, phosphoric acid, pyrophosphoric acids, metaphosphoric acids, ethylmetaphosphoric acid, polyphosphoric acid, phosphorus pentoxide, and phosphoric pentachloride at a temperature ranging from about 195C to about 205C until a polyamide-imide resin having a reduced viscosity of 0.2 to 0.5 dl/g as measured at a concentration of 0.5 g/dl in dimethylformamide at 30C is produced; and (b) a second reaction stage which comprises adding a phosphorus triester as a second dehydration catalyst to the reaction mixture resulting from the first reaction stage and further reacting the reaction mixture at a temperature ranging from about ~80C to about 190-C until a high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above as measured at a concentration of 0.5 g/dl in dimethylformamide at 30C is produced; the first dehydration catalyst being used in an amount of 0~5 to 20% by weight on the basls of the total of the trimellitic acid derivative (I) and the aromatic diamine (II), and the one or more compounds (III) and the phosphorus triester as a second dehydration catalyst being used in an amount of 0.1 to 50% by weight on the basis of the total of the trimellitic acid derivative (I) : the aromatic diamine (II) and the one or more compounds (III).
.,.~, ~, ~'' - 6a -BRIEF DESCRIPTION OF DRAWING
Figure 1 shows the relationship between reaction time and reduced viscosity in Example 2 and Comparative Examples 1 and 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Some illustrative examples of (I) trimellitic acid derivatives to be used in the present invention include trimellitic acid anhydride and esters of trimellitic acid or trimellitic acid anhydride with an alcohol. Typical examples of the esters of trimellitic acid or trimellitic acid anhydride with an alcohol are monomethylesters o~ trimellitic acid or trimellitic acid anhydride. The pre~erred trimellitic acid derivative is trimellitic acid anhydride.
Some illustrative examples o~ (IIj aromatic ~ 131S463 1 diamines to be used in the pre.sent invention include m-phenylenediamine, p-phenylenediamine, 4,4' -diaminodiphenylpropane, 4,4' -diaminodiphenylmethane, 4,4' -diaminodiphenyl sulfide, 4,4' -diaminodiphenyl sulfone, 4,4' -diaminodiphenyl ether, 1,5-diaminonaphthalene, 3,3' -diaminobiphenyl, 3,3' -dimethoxybenzidine, 1,3-diamino-4-isopropylbenzene, xylylenediamine, 4,4~ -diaminoterphenyls, 4,4"' -diaminoquarterphenyl, 1,4-bis(p-aminophenoxy)benzene, 4,4' -bis(p-aminophenoxy)diphenyl sulfone~ ~
4,4' -bis(p-aminophenoxy)biphenyl, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bisl4-(4-aminophenoxy)phenyl~hexafluoropropane, 4,4' -diaminoben~ophenone, benzidine-2,3,5,6-tetramethyl-p-phenylenediamine, diaminotoluenes, tetrafluorophenylened1amines, and diaminooctafluorobiphenyls. These compounds may be used indlvidually or as a mixture thereof. In consideration o-f 20 ~ heat resistance and economical e~ficiency, the preferred aromatic diamines are 4~4' -dlaminodiphenylmethane, 4,4' -diaminodiphenyl ether,~p-phenylenediamine, and m-phenylenediamine.
The preferred polar solvents to be used in the present invention are those being capable of easily 1 dissolving the produced polyamide-imide resins and having a boiling point o~ 180C or above. Some illustrative examples o~ the preferred polar solven1;s 1nC1Ude N-methylpyrrolidone, N-ethylpyrrolidone, N-butylpyrrolidone, phenol, cresols, xylenols, r -butyrolactone, and sulfolane.
Among these, the particularly pre~erred is N-methylpyrrolidone.
Some illustrative examples of the first dehydration catalysts to be used in the present invention in the first reaction stage include boric acid and boric acid derivatives such as boric anhydride; pentavalent phosphorus compounds, for example, phosphoric acid, pyrophosphorlc acid, metaphosphoric acids such as trimetaphosphoric acid, ethylmetaphosphorie acid, polyphosphoric acids such as tetrapolyphosphoric acid, :
phosphorus pentoxide, and phosphorlc pentachloride. The preferred are phosphoric acid, polyphosphoric acids, boric acid, and boric anhydride, and the particularly preferred ls phosphoric acid.
The second dehydration catalysts to be used in the present invention in the second re~ction stage are phosphorous triesters~represented by the formula (R0)3P, wherein R is an aliphatic or aromatic su~stituent such as methyl, ethyl, isopropyl, butyl, 2-ethylhexyl, isooctyl, decyl, lauryl, phenyl, methylphenyl, ethylphenyl, 1 butylphenyl, octadecylphenyl, nonylphen~l, diphenylnonyl, biphen~l~l, cyclohexyl, and indenyl; and the preferred is triphanyl phosphite.
In the present invention, ~I~ trimellitic acid derivative and (II) arosnatic diamine are used preferably in an amount equimolar with each other, and the particularly preferable molar ratio, (II)/~I), is from 0.98 to 1.02.
In the present invention, one or more compounds (III) selected from the group consisting of (A) dicarboxylic acids and (B) lactams in addition to the (I) trimellitic acid derivative and (II) aro~atic diamine mentioned above may be used as materials at need.
Some illustrative examples of the (A) ~
dicarbo~ylic acids~which may be~used in the present inverlt10n include succinic aeid, adipic acid, sebacic acid, dodecanedicarboxylic acid, isophthalic acid, and terephthalic acid. In consideration of heat resistance and solubility o-~ the product resins, isophthalic acid is prefe~ably used.
In case of using the (A) dicarboxylic acids, it is desirable, in conslderation of heat resistance and flowability at the time of moldlng process, to use (A) as a part of acid component in an amount of 0.05 to O.S0 mol, preferably 0.1 to Q.3 mol per 1 mol of the (II) aromatic diamine.
1 31 ~463 1 Some illustrative examples of the (B) lactams which may be used in the present invention include lactams represented by the following general formu:La:
NH ~ C0 ~ ( C:~I2 ) r~/
wherein, n is an integer of from 2 to 20, and the preferred is ~ -caprolactam.
From the viewpoint of heat resistance and flowability at the time of molding process. it is desirable to use (B) in an amount of 0.05 to 0.50 mol, pre~erably 0.05 to 0.30 mol per 1 mol of the (II) aromatic diamine.
According to the present invention, acid component and amine component are reacted firstly in the : : ~ first reaction stage using the first dehydration catalyst until the reduced viscosity of polyamide-imide resin : produced reaches 0.2 to 0.5 dl/g, and the reaction is : further progressed by adding a phosphorous triester as the ; 20 second dehydration catalyst to increase the reduced ~iscosity of the polyamide-imide resin to 0.3 dl~g or above.
If the first reaction stage is concluded before : the reduced vi,scosity reaches 0.2 dl/g, the amount o~ the : : 25 second dehydration catalyst required wiIl be approximatelY
~15463 1 equivalent to the amount of acid component or amine component, causing the sa~e problem as that caused by separate use of the second dehydration catalyst. If the reduced viscosity exceeds 0.5 dl/g, partial gelation or runaway reaction will occur at the time of addition of the second dehydration catalyst, causing a di-friculty in controlling the molecular weight. The reduced viscosity of the polyamide-imide resin obtained in the second reaction stage should be 0.3 dl/g or above. In consideration of heat resistance, mechanical strength or the llke, the preferable reduced viscosity is 0.4 or above.
From the viewpoint of reactivity and facility~of purification, it is preferable to use the first dehydration catalyst of the present invention in an amount of 0.5 to 20 % by weight on the basis of total of the reaction species including (I) and ~II) or~ (I), (II) and (III). The particularly preferable amount is l to 5 % by weight.
From the view point of reactivity and facility of reaction control, it is preferable to use the second dehydration catalyst in an amount of 0.1 to 50 % by weight on the basis of total of the reaction species including (I) and (II) or ~I), (II) and (III). The particularly preferable amount is 3 to 30;X by weight.
In the present invention, the total concentration of the reactants of the polymerization system during the 1~
1 first reaction stage using the ~irst dehydration catalyst is preferably about 50 to 60 % by weight, and that during the second reaction stage using -the second dehydration catalyst is preferably about 30 to 40 % by weight. With regard to the reaction temperature, it is desirable to add the ~irst dehydration catalyst at a temperature in the vicinity of 170C , then carry out polymerization at a temperature in the vicinity o-f 195 to 205C , and conduct the addition o~ the second dehydration catalyst and the reaction in the second reaction stage at a temperature range of about 180 to 190C .
It is desirable to carry out the ~irst reaction stage and second reaction stage in an atmosphere of an inert gas such as nitro~en.
The polyamide-imlde resins obtained by the present invention may be protected with end-group blocking agents at the end of the polymerization reaction. The end-group protection increases the heat stability at the time20 o-~ molding.
The end-group blocking agents which may be used include, ~or example, phthalic anhydride, benzoic acid, acetic anhydride, aniline, n-butylamine, and phenyl isocyanate.
Z5 The polyamide-imide resins obtained by the 1 present invention may be, if desired, further diluted by adding the above-described polar solvents or low boiling point organic solvents, such as chloroform, tetrahydrofuran, diox~ne, toluene, and xylene, to the product solution resulting from the polymerization.
The polyamide-imide resins obtained hy the present invention may be used in solution state or powder state and also may be blended with other kinds o~ polymers, additives, fillers, reinforcing agents, etc., if de.sired.
The polyamide-imide resins obtained by the present invention, at need, may be improved o-f their physical properties extremely by heating them (for example, at 200 to 300~ for 1 to 24 hours) after molding.
According to the present invention, high molecular weight polyamide-imide resins having excellent heat resistance, melt flowability, and economical efficiency can be obtained.
~ :
The polyamlde-imide resins obtained by the present invention are suitable for the use of thermoplastic moldlng materials and are~ also useful as, ~or example, heat resistant materials ~or~heat resistant paints, heat resistant sheet~, heat resistant adhesives, heat resistant la~inating materials, heat resistant sliding materials, heat resistant fibers, heat resistant films, and the like.
In order to more fully and clearly illustrate the ~ ' 1315~63 1 present invention the following examples are set ~orth. It is intended that the examples be considered as illustrative rather than limiting the invention as disclosed and claimed herein.
The following examples also illustrate processes falling outside the scope of the instant invention and are presented for comparative purposes only.
EXAMPLES 1 to 5 and COMPARATIVE EXAMPLES 1 to 5 EX~MPLE 1 Mol ratio g wt. part trimellitic acid anhydride1.00 192 48.7 4,4' -diaminodiphenylmethane1.02 202 51.3 a~ueous phosphoric acid solution 0.02 2.3 0.5 (content of phosphoric acid: 85 %) N-methylpyrrolidone - 394 100 triphenyl phosphite 0.13 40 10 : ~ :
Irlto a four necked flask equipped with a stirrer, a nitrogen introduction tube, and an apparatus for moisture determination were placed the above components except triphenyl phosphlte, and the con~ent was dissolved by raising the temperature slowly to 180C with stirring under introduction of nitrogen gas. Subsequently, the resulting ~ ,~ ,, 1 solution was further heated to 210C and reaction was continued while removing rapidly ~he distilled water out of the reaction syskem and at the same time filling up the distilled N-methylpyrrolidone (first reaction stage). The progress of reaction was watched by measuring~the increase of molecular weight of the polymer with ~PLC (high per~ormanee liquid chromatography) to obtain a polyamide-imide resin having a reduced viscosity o~ U.3 dl~g as measured at a concentration of 0.5 g/dl in dimethylformamide at 30C . Subsequently, the resin concentration was diluted to 35 % by weight by adding N-`methylpyrrolldone and the reactlon temperature was lowered to 180C . Triphenyl phosphite was added in 5 portions over a period of 2 hours and the reactlon was continued (~second~
reaction stage). The end point o* the reaction was determined by measuring the molecular weight with~HPLC.
: ~ :
Thus a polyamide-imide resin~having a reduced viscosity of 0.65 dl/g was Pinally obtained. Nothlng unusual such as scorching o-f resin to the inner wall of the flask or gelation was observed.~
Mol ratio g wt. part trimellitic acid anhydride 1.00 192 48.7 1315~63 1 4,4' -diaminodiphenylmethane 1.02 202 51.3 aqueous phosphoric acid solution 0Ø223.2 5 (content of phosphoric acid: 85 %) N-methylpyrrolidone - 394 100 triphenyl phosphite 0.3.2 98.5 25 The procedure of Example 1 was repeated with the exception that the above components were used. First, first reaction was carried out to obtain a polyamide-imide resin having a reduced viscosity of 0.45 dlig.
Subsequently, second reaction was carried out to obtain a polyamide-imide resin having a -final reduced viscosity of 0.8 dl/g. Nothing unusual such as scorching of resin to the lnner wall oY the flask or gelation was observed.
. :
15 : EXAMPLE 3 :
Mol ratio g wt. part trlmellitic acid anhydride 1.00 192 48.7 4,4' -diaminodiphenylmethane 1.02 202 51.3 aqueous phosphoric acid solutlon 0.32 37.l 8 : ~ (content of phosphoric acid: 85 %) N-methylpyrrolidone - 394 100 : triphenyl phosphite : 0.065 2.0 0.5 The procedure of Exa~mple 1 was repeated with the ~5 exception that the above components were used. F:lrst, t 31 ~463 1 first reaction was carried out to obtaln a polyamide-imide resin having a reduced viscosity Or 0.3 dl/g.
Subsequently, second reaction was carried out to obtain finally a polyamide-imide resin having a reduced viscosity o-f 0.6 dl~g. Nothing unusual such as scorching o~ resin to the inner wall of the flask or gelation was observed.
~ol ratio g wt. part trimellitic acid anhydride 0.90 172.841.7 4,4' -diaminodiphenylmethane 1.02 202.048.8 isophthalic acid 0.10 16.64.0 ~ -caprolactam 0.20 22.65.5 aqueous phosphoric acid solution 0.21 24.3 5.9 (content of phosphoric acid: 85 %) N-methylpyrrolidone - 414 100 triphenyl phosphite 0.33 103,525 The procedure o~ Example 1 was repeated with the exception that the above components were used. First, ~irst reaction was carried out to obtain a polyamide-imide resin having a reduced viscosity of 0.3 dl/g.
Subsequently, second reaction was carried out to obtain a polyamide-imide resin having a reduced viscos~ty of 0.8 ~5 dl/g. Nothing unusual such as scorching of resln to the 13~5~63 1 inner wall of the flask or gelation was observed.
EX~MPLE 5 Mol ratio g wt. part trimellitic acid anhydride 0.85 163.2 ~0.6 4,4' -diaminodiphenylmethane 1.02 202.0 50.3 isophthalic acid 0.15 24.9 6.2 ~ -caprolactam 0.10 11.3 2.8 aqueous phosphoric acid solution 0.024 2.4 0.
: (content of phosphoric acid: 85 ~
N-methylpyrrolidone - 401.4 100 triphenyl phosphite 0.52 1~0.5 40 The procedure of Example 1 was repeated with the ~: 15 exception that the above component~ were used. First, first reaction was carried out to obtain a polyamide-imide : resin having a reduced viscosity of 0.45 dl/g.
Subsequently, second reaction was carried out to obtain a polyamide i~ide resin having a final reduced viscosity of 1.0 dl/g. Nothing unusual such as scorching of resin to the inner wall of the flask or gelation was ob~erved.
: ~ :
:
131~4~3 Mol ratio g wt. part trimellitic acid anhydride l.Q~ 19~ 48.7 4,4' -diaminodiphenylmethane 1.02 202 51.3 N-methylpyrrolidone - 394 100 Into the same type four-necked ~lask as that used in Example 1 were placed the above components and the content was dissolved by raising the temperature slowly to 180C with stirring under introductlon of nitrogen gas.
Subsequently, the resulting solution was ~urther heated to 210C and reaction was progressed, while the distilled~
water was rapidly removed o~ out of the reaction system ; 15 and at the same time the distilled N-~ethylpyrrolidone was filled op (first react~on stage). The progress of reaction was monitered by measuring the increase of molecular weight with HPLC to obtain a polyamide-imide resin having a ~ reduced viacoslty of 0.18 dl/g as measured at a ; ~20 concentration of~ 0.5~ g/dl in dlmethylformamide at 30C .
~ ~ The reac~ion product was a low viscoslty liquid.
:~: : :
1315~63 Mol ratio g wt. part trimellitic acid anhydride 1.00 192 48.7 4 ? 4' -diaminodlphenylmethane1.02 202 51.3 N-methylpyrrolidone - 394 100 aqueous phosphorlc acld solution 0.60 69.5 15 (content o~ phosphoric acid: 85 %) The procedure o~ the reaction stage 1 o~ Example 1 was repeated with the exception that the above components : were used, to obtain a polyamide-imide resin having a reduced v~scosity o~ 0.45 dl/g. However, since a:high temperature and a long reaction tlme (210C - 25 hours) were required -~or the reaction, scorchlng occurred on the bottom of the ~lask.~ :
Mol ratio g :wt. part 20~ trimellitic acld anhydride: 1.00 192 48.7 4,4' -diaminodiphenylmethane 1.02 202 51.3 N-methylpyrrolidone - 394 100 triphenyl phosphite 0.76 236 59.9 The procedure o~ the ~irst reaction stage o~
1 Example 1 was repeated with the exceptlon that the above components were used, to obtain a polyamide-imide resin having a reduced viscosity o-~ 0.18 dl/g. Subsequently, the resin concentration was decreased to 3~ % by wei~ht by adding N-methylpyrrolldone, and th~ reaction temperature was lowered to 180 to 190C . While the reaction was progressed by adding triphenyl phosphite in 5 portions over a period o~ 2 hours, the viscosity o~ varnish was rapidly increased and gelatinized.
Mol ratio g wt. part trimellitic acid anhydride 1.00 19248.7 4,4' -diaminodiphenylmethane 1.02 202 51.3 I
N-methylpyrrolldone - 394 100 aqueous phosphoric acid solution 0.02 0.23 0.06 (content of phosphoric acid: 85 %) triphenyl phosphite 0.76 236 60 The procedure of Example l was repeated with the exception that the above components were used. First, first reaction stage was carrled out to obtaln a polyamide-imide having ~ reduced viscosity of 0.18 dl/g.
Subsequently, triphenyl phosphite was added and reactlon was progressed ~or about 30 mlnu~es (second reaction .
.
1 stage). The reduced viscosity o-~ vanish was increased and the varnish was gelatinized at the end.
Mol ratio g wt. part trimellitic acid anhydridel.OO 192 4~.7 4,4' -dLaminodiphenylmethane1.02 202 51.3 N-methylpyrrolidone - 394 100 aqueous phosphoric acid solution 0.60 69.6 15 (content o~ phosphoric acid: 85 %) triphenyl phosphite 0.0064 1.97 0.05 The procedure of Example 1 was repeated w1th the~
exception that the above componente were used. First, I
1 15 first reaction stage was carrled out to obtain a polyamide-: .
imide resin having a reduced viscos1ty of 0.35 dl/g.
Subsequently, the second stage polymerization was attempted. However, polymerization to a high molecular w~eight polyamide-imide -~ailed to proceed under the reaction ~; 20 condltions, resulting in a solution with a final redueed ylscoslty o-~ 0.38 dl/~.
~ Films were produced from the polyamide-imide -~ resins obtained ln E~amples 1 to 5 and Co~parative E~amples 1 to 5 and glass transition tem~erature was mea ured with a thermomechanical analyzer. The results and the appearance of reaction in the course o-f synthesis were shown in Table 1.
:: :
:
~: 20 :: ` :
:
~: 2 5 u~ c~ o I I L/~ ~ o o o o o ~ o C~ C~ O C~, C~ :Z ._ ~ o C~ o ,o~
~ o C:~ o I I o ~o oo I o ~ I
X Z ~ ~1 0 O O
~ o o I I I ~o ~ I o .~ I
~ 2: ~ _ ~4, E C`l C`:l O I I Ln I I Ln LE~
c~ o o ~ I I ~r C~ X C~l ._ ~ O ~
C`~ O I I O I I CO ~ 0 2: o o o cY:)OO a) Ll~ ~0 ~ ~ ~ O ~ O C~ O U~
O ~ O o o o O ~ C~l O a~ C~ CO ~3 0 Ct~
:Z: ~ O O O O O C`~
Q~ C.~ O I I 00 u~ h~ CD ~ O
E Z .~ O O O C`~
.-1 X .
~ O ~ 0 1 1 ~ ~ L~ 00 C`~
~ :Z _ ._ O Q~
: ;Z ~ O I I ~ -4 o ~D ~ O ~ C
--O ~ C .
E O ~ ~ ~
~ h 3 ~ h ~ b E ~ ~ ~ .C_) l O h ~_ :~ C h ~ 3 .~ _. : 2) r ~ ~ ~1) h c~
,C~ ~ .. C E ~ Cl. ,1:: ~ O
~C ~ O O :~ C~ ~
E ~ _ O ~ -- ~ O ~ E ~:
.~ al h h :~ ~: h . ~
~ o .~ ~ b ~ o I a~ .c ~ Q ~ ~ Q) _, et' ~4 0 1 0 ~-- ~ ta c: Il) ._ ~
_ ~ 07 ~'~CL h ~ o~ t~ ,E ~ ~7 CS
c ~ ~ v~ e .~ ~ ~ O O b a~
O h O 8 o ~ ~ ~ 3 o e ~ $ a~ c~ ~
!S~b ;
t315~63 1 The relationships between reaction time and reduced viscosity in Example 2 and Comparative Examples 1 and 2 are shown in Fi~ure 1.
The reaction appearance shown in the Table 1 was ~udged by examinlng the occurrence of scorching on the flaskls wall or generation o~ gelatinized matter. O
represents absence, and x represents presence.
~ he measuremen-t o~ glass transition temperatures (Tg) of films were conducted using a thermomechanical analyY,er of Perkin Elmer TMS-1.
Measuring conditions tension method temperature raising rate: 10C /min, load: 5 g, sample: 2 mm width, spun: 10 ~n Production o~ ~ilm 25 wt.% varnish was applied over a clean glass plate with an applicator to a thlckness o~ 80 ~ m and was 2~ then heated for 30 minutes with a 250C hot air dryer to obtain a film of about 20 ~ m thlckness.
Claims (35)
1. A process for producing high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above by reacting a trimellitic acid derivative (I) selected from the group consisting of trimellitic acid anhydride and an ester of trimellitic acid or trimellitic acid anhydride with an alcohol and an aromatic diamine (II), in the presence of a polar solvent and dehydration catalyst, which process comprises the two reaction stages:
(a) a first reaction stage which comprises reacting the trimellitic acid derivative (I) and the aromatic diamine (II) in the presence of a polar solvent in the presence of a first dehydration catalyst selected from the group consisting of boric acid, boric anhydride, phosphoric acid, pyxophosphoric acids, metaphosphoric acid, ethylmetaphosphoric acid, polyphosphoric acid, phosphorus pentoxide, and phosphonic pentachloride at a temperature ranging from about 195°C to about 205°C until a polyamide-imide resin having a reduced viscosity of 0.2 to 0.5 dl/g as measured at a concentration of 0.5 g/dl in dimethylformamide at 30°C is produced; and (b) a second reaction stage which comprises adding a phosphorus triester as a second dehydration catalyst to the reaction mixture resulting from the first reaction stage and further reacting the reaction mixture at a temperature ranging from about 180°C to about 190°C until a high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above as measured at a concentration of 0.5 g/dl in dimethylformamide at 30°C is produced; the first dehydration catalyst being used in an amount of 0.5 to 20% by weight on the basis of the total of the trimellitic acid derivative (I) and the aromatic diamine (II), and the phosphorus triester as a second dehydration catalyst being used in an amount of 0.1 to 50% by weight on the basis of the total of the trimellitic acid derivative (I) and the aromatic diamine (II).
(a) a first reaction stage which comprises reacting the trimellitic acid derivative (I) and the aromatic diamine (II) in the presence of a polar solvent in the presence of a first dehydration catalyst selected from the group consisting of boric acid, boric anhydride, phosphoric acid, pyxophosphoric acids, metaphosphoric acid, ethylmetaphosphoric acid, polyphosphoric acid, phosphorus pentoxide, and phosphonic pentachloride at a temperature ranging from about 195°C to about 205°C until a polyamide-imide resin having a reduced viscosity of 0.2 to 0.5 dl/g as measured at a concentration of 0.5 g/dl in dimethylformamide at 30°C is produced; and (b) a second reaction stage which comprises adding a phosphorus triester as a second dehydration catalyst to the reaction mixture resulting from the first reaction stage and further reacting the reaction mixture at a temperature ranging from about 180°C to about 190°C until a high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above as measured at a concentration of 0.5 g/dl in dimethylformamide at 30°C is produced; the first dehydration catalyst being used in an amount of 0.5 to 20% by weight on the basis of the total of the trimellitic acid derivative (I) and the aromatic diamine (II), and the phosphorus triester as a second dehydration catalyst being used in an amount of 0.1 to 50% by weight on the basis of the total of the trimellitic acid derivative (I) and the aromatic diamine (II).
2. The process of claim 1, wherein the first dehydration catalyst is selected from the group consisting of phosphoric acid, polyphosphoric acids, boric acid, and boric anhydride.
3. The process of claim 2, wherein the first dehydration catalyst is phosphoric acid.
4. The process of claim 1, wherein the phosphorous triester as a second dehydration catalyst is selected from the compounds having the structure represented by the following general formula:
(RO)3P
wherein R is selected from the group consisting of methyl, ethyl, isopropyl, butyl, 2-ethylhexyl, isooctyl, decyl, lauryl, phenyl, methylphenyl, ethylphenyl, butylphenyl, octadecylphenyl, nonylphenyl, diphenylnonyl, biphenylyl, cyclohexyl, and indenyl.
(RO)3P
wherein R is selected from the group consisting of methyl, ethyl, isopropyl, butyl, 2-ethylhexyl, isooctyl, decyl, lauryl, phenyl, methylphenyl, ethylphenyl, butylphenyl, octadecylphenyl, nonylphenyl, diphenylnonyl, biphenylyl, cyclohexyl, and indenyl.
5. The process of claim 4, wherein the phosphorous triester as a second dehydration catalyst is triphenyl phosphite.
6. The process of claim 1, wherein the first dehydration catalyst is used in an amount of 1 to 5 % by weight on the basis of the total of the trimellitic acid derivative (I) and the aromatic diamine (II), and the phosphorous triester as a second dehydration catalyst is used in an amount of 3 to 30% by weight on the basis of the total of the trimellitic acid derivative (I) and the aromatic diamine (II).
7. The process of claim 1, wherein the trimellitic acid derivative (I) is trimellitic acid anhydride.
8. The process of claim 1, wherein the aromatic diamine (II) is selected from the group consisting of 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, p-phenylenediamine, and m-phenylenediamine.
9. The process of claim 8, wherein the aromatic diamine (II) is 4,4'-diaminodiphenylmethane.
10. The process of claim 1, wherein the polar solvent is selected from the group consisting of N-methylpyrrolidone, N-ethylpyrrolidone, N-butylpyrrolidone, phenol, cresols, xylenols, .lambda.-butyrolactone, and sulfolane.
11. The process of claim 10, wherein the polar solvent is N-methylpyrrolidone.
12. A process for producing high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above by reacting a trimellitic acid derivative (I) selected from the group consisting of trimellitic acid anhydride and an ester of trimellitic acid or trimellitic acid anhydride with an alcohol and an aromatic diamine (II), and one or more compounds (III) selected from the group consisting of (A) dicarboxylic acids and (B) lactams, in the presence of a polar solvent and dehydration catalyst, which process comprises the two reaction stages:
(a) a first reaction stage which comprises reacting the trimellitic acid derivative (I) and the aromatic diamine (II), and one or more compounds (III) selected from the group consisting of (A) dicarboxylic acids and (B) lactams, in the presence of a polar solvent in the presence of a first dehydration catalyst selected from the group consisting of boric acid, boric anhydride, phosphoric acid, pyrophosphoric acids, metaphosphoric acids, ethylmetaphosphoric acid, polyphosphoric acid, phosphorus pentoxide, and phosphoric pentachloride at a temperature ranging from about 195°C to about 205°C until a polyamide-imide resin having a reduced viscosity of 0.2 to 0.5 dl/g as measured at a concentration of 0.5 g/dl in dimethylformamide at 30°C is produced; and (b) a second reaction stage which comprises adding a phosphorus triester as a second dehydration catalyst to the reaction mixture resulting from the first reaction stage and further reacting the reaction mixture at a temperature ranging from about 180°C to about 190°C until a high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above as measured at a concentration of 0.5 g/dl in dimethylformamide at 30°C is produced; the first dehydration catalyst being used in an amount of 0.5 to 20% by weight on the basis of the total of the trimellitic acid derivative (I) and the aromatic diamine (II), and the one or more compounds (III) and the phosphorus triester as a second dehydration catalyst being used in an amount of 0.1 to 50% by weight on the basis of the total of the trimellitic acid derivative (I) the aromatic diamine (II) and the one or more compounds (III).
(a) a first reaction stage which comprises reacting the trimellitic acid derivative (I) and the aromatic diamine (II), and one or more compounds (III) selected from the group consisting of (A) dicarboxylic acids and (B) lactams, in the presence of a polar solvent in the presence of a first dehydration catalyst selected from the group consisting of boric acid, boric anhydride, phosphoric acid, pyrophosphoric acids, metaphosphoric acids, ethylmetaphosphoric acid, polyphosphoric acid, phosphorus pentoxide, and phosphoric pentachloride at a temperature ranging from about 195°C to about 205°C until a polyamide-imide resin having a reduced viscosity of 0.2 to 0.5 dl/g as measured at a concentration of 0.5 g/dl in dimethylformamide at 30°C is produced; and (b) a second reaction stage which comprises adding a phosphorus triester as a second dehydration catalyst to the reaction mixture resulting from the first reaction stage and further reacting the reaction mixture at a temperature ranging from about 180°C to about 190°C until a high molecular weight polyamide-imide resin having a reduced viscosity of 0.3 dl/g or above as measured at a concentration of 0.5 g/dl in dimethylformamide at 30°C is produced; the first dehydration catalyst being used in an amount of 0.5 to 20% by weight on the basis of the total of the trimellitic acid derivative (I) and the aromatic diamine (II), and the one or more compounds (III) and the phosphorus triester as a second dehydration catalyst being used in an amount of 0.1 to 50% by weight on the basis of the total of the trimellitic acid derivative (I) the aromatic diamine (II) and the one or more compounds (III).
13. The process of claim 12, wherein the first dehydration catalyst is selected from the group consisting of phosphoric acid, polyphosphoric acids, boric acid, and boric anhydride.
14. The process of claim 13, wherein the first dehydration catalyst is phosphoric acid.
15. The process of claim 12, wherein the phosphorous triester as a second dehydration catalyst is selected from the compounds having the structure represented by the following general formula:
(RO)3P
wherein R is selected from the group consisting of methyl, ethyl, isopropyl, butyl, 2ethylhexyl, isooctyl, decyl, lauryl, phenyl, methylphenyl, ethylphenyl, butylphenyl, octadecylphenyl, nonylphenyl, diphenylnonyl, biphenylyl, cyclohexyl, and indenyl.
(RO)3P
wherein R is selected from the group consisting of methyl, ethyl, isopropyl, butyl, 2ethylhexyl, isooctyl, decyl, lauryl, phenyl, methylphenyl, ethylphenyl, butylphenyl, octadecylphenyl, nonylphenyl, diphenylnonyl, biphenylyl, cyclohexyl, and indenyl.
16. The process of claim 15, wherein the phosphorous triester as a second dehydration catalyst is triphenyl phosphite.
17. The process of claim 12, wherein the first dehydration catalyst is used in an amount of 1 to 5% by weight on the basis of the total of the trimellitic acid derivative (I), the aromatic diamine (II) and one or more compounds (III), and the phosphorous triester as a second dehydration catalyst is used in an amount of 3 to 30% by weight on the basis of the total of the trimellitic acid derivative (I), the aromatic diamine (II), and one or more compounds (III).
18. The process of claim 12, wherein the trimellitic acid derivative (I) is trimellitic acid anhydride.
19. The process of claim 12, wherein the aromatic diamine (II) is selected from the group consisting of 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, p-phenylenediamine, and m-phenylenediamine.
20. The process of claim 19, wherein the aromatic diamine (II) is 4,4'-diaminodiphenylmethane.
21. The process of claim 12, wherein the dicarboxylic acids (A) are succinic acid, adipic acid, sebacic acid, dodecanecarboxylic acid, isophthalic acid, and terephthalic acid.
22. The process of claim 12, wherein one or more of the dicarboxylic acids (A) are used in an amount of 0.05 to 0.50 mol per 1 mol of the aromatic diamine (II).
23. The process of claim 22, wherein one or more of the dicarboxylic acids (A) are used in an amount of 0.1 to 0.3 mol per 1 mol of the aromatic diamine (II).
24. The process of claim 12, wherein the lactams (B) are compounds represented by the following general formula:
wherein n is an integer of 2 to 20.
wherein n is an integer of 2 to 20.
25. The process of claim 12, wherein one or more of the lactams (B) are used in an amount of 0.05 to 0.50 mol per 1 mol of the aromatic diamine (II).
26. The process of claim 25, wherein one or more of the lactams (B) are used in an amount of 0.05 to 0.30 mol per 1 mol of the aromatic diamine (II).
27. The process of claim 12, wherein the compound (III) is isophthalic acid.
28. The process of claim 12, wherein the compound (III) is .epsilon.-caprolactam.
29. The process of claim 12, wherein the compounds (III) are isophthalic acid and .epsilon.-caprolactam.
30. The process of claim 12, wherein the polar solvent is selected from the group consisting of N-methylpyrrolidone, N-ethylpyrrolidone, N-butylpyrrolidone, phenol, cresols, xylenols, .lambda.-butyrolactone, and-sulfolane.
31. The process of claim 30, wherein the polar solvent is N-methylpyrrolidone.
32. The process of claim 1, wherein the first reaction stage and the second reaction stage are carried out in an atmosphere of an inert gas.
33. The process according to claim 32, wherein the inert gas is nitrogen.
34. The process according to claim 12, wherein the first reaction stage and the second reaction stage are carried out in an atmosphere of an inert gas.
35. The process according to claim 34, wherein the inert gas is nitrogen.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000590859A CA1315463C (en) | 1987-08-20 | 1989-02-13 | Process for the production of high molecular weight polyamide-imide resin |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62207231A JPS6451438A (en) | 1987-08-20 | 1987-08-20 | Production of high-mw polyamide-imide resin |
| CA000590859A CA1315463C (en) | 1987-08-20 | 1989-02-13 | Process for the production of high molecular weight polyamide-imide resin |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1315463C true CA1315463C (en) | 1993-03-30 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000590859A Expired - Fee Related CA1315463C (en) | 1987-08-20 | 1989-02-13 | Process for the production of high molecular weight polyamide-imide resin |
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| Country | Link |
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| CA (1) | CA1315463C (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116194513A (en) * | 2020-09-22 | 2023-05-30 | 艾伦塔斯欧洲有限公司 | Wire enamel composition comprising polyamideimide |
-
1989
- 1989-02-13 CA CA000590859A patent/CA1315463C/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116194513A (en) * | 2020-09-22 | 2023-05-30 | 艾伦塔斯欧洲有限公司 | Wire enamel composition comprising polyamideimide |
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