DE1795319C3 - Process for the preparation of polybenzimidazoles and their use - Google Patents

Description

IO

NH-R ₁ -NH ₂

NH ₂ NH-R ₁ -NIl

NH ₂

20th

in which R _{1 is} divalent aromatic radicals that are not or: ho- or peri-oriented, and R ₂ and R ₃ , which are identical or different, each have water- «toffatoine, lower aliphatic hydrocarbon radicals with 1 to 3 carbon atoms or R ₄ O- © of the R _{s are} OOC radicals, where R ₄ and R _{5 are} alkyl radicals having 1 to 3 carbon atoms or phenyl radicals, and optionally up to 50 mol percent of aliphatic diamines or diamines of the general formula

Hen can, however, use aromatic polyamines can J and / or secondary amino

^mI i? n place of the diamines are used, Sn k ^a eL i! ^le Lös ^e un _g smitte.n .ösliche hochmolekuTarr polymers are obtained by reaction of these polyamines and ^ carbonyl halides, son-5 "rn" s are typically crosslinked, obtained in solvents insoluble polymers.

An example of a reaction of an aromatic terramine with a dicarboxylic acid dihalogeni-i for the purpose of S llung is a precursor of a polybenzim.dazo s in Journal of Polymer Science, Vol. 50,528 (1961), where 3,3'-diaminobenzidine or 1 2,4,5-tetraminobenzene and an aromatic dicarboxylic acid chloride subjected to interfacial polycondensation will.

This example results in polyamide amines of fairly low molecular weight whose E.gen-

sLities measured at a 0.2% concentration of polymer in sulfuric acid, between 0.09 and 0.22. These polyamide amines were only i.i Sulfuric acid soluble and insoluble in all organic solvents, even if the inherent viscosity of polymers as low as

HN-R, -NH II

R, R ₈

35

in which R. ₆ denotes a divalent aromatic radical, R ₇ and R ₈ , which are identical or different, denote hydrogen atoms or alkyl radicals having 1 to 3 carbon atoms, the NHR ₇ and NHR ₈ radicals being bonded to core carbon atoms and not in ortho - Or are peri-position on R ₆ , with aromatic dicarboxylic acid dihalides of the general formula

HaIOC-R ₉ -COHaI

in which Hal is a halogen atom and R _{9 is} a divalent aromatic radical, the two COHal radicals not being in the ortho or peri position, in R ₉ , having been prepared at temperatures from -20 to 50 ¹ C in inert organic solvents Temperatures above 200 ° C or in the presence of acidic compounds above 60'C heated.

2. Use of the polybenzimidazoles obtained according to claim 1 as molded articles or Coatings.

It is known that linear high molecular weight polyymides are obtained by polycondensation of aromatic dimines and dicarboxylic acid halides. or a Roman from (1.) an aromatic compound that contains two o-Dia.ninosubstituenten on the aromatic nucleus and (2.) the diphenyl ester of an aromatic or heterocyclic dicarboxylic acid, the carboxyl groups on the nucleus, at least 30 minutes under reduced pressure the melt condensation is subjected, and optionally pulverizing the PoIykondensat formed and under reduced pressure '' ine temperature of at least 25O ⁰ C for a period of at least about 2 hours weitererhiizt (DT-aS 1 197 229). However, the products obtained are only in sulfuric acid soluble and not in other organic solvents.

The object of the invention is therefore to create a process for the preparation of polybenzimidazoles being the precursor to this, namely polyamidimines' in a variety of organic solvents are soluble in high concentration and are therefore used as paints and varnishes be able.

The invention is a method for Production of polybenzimidazoles, which is characterized in that one polyamide imines, which by Implementation of aromatic triamines or tetranines of the general formula

NH ₂ NH-R ₁ -NH ₂

NH-R ₁ -NH

R.,

NH,

in which R ₁ is divalent aromatic radicals which are not ortho-or peri-oriented are, and R., and R _3, which are identical or different, each represent hydrogen atoms, lower aliphatic hydrocarbon radicals _w ith 1 to 3 carbon atoms, or R ₄ O- or R _{5 represent} OOC radicals, where R ₁ and R _{5 represent} alkyl radicals having 1 to 3 carbon atoms or phenyl radicals, and optionally up to 50 mol percent of aliphatic diamines or diamines of the general formula

HN- R _(> - NH
R ₇ R ₈

15th

in which R _{e is} a divalent aromatic radical, R ₇ and R ₈ , which are identical or different, represent hydrogen atoms or alkyl radicals with 1 to 3 carbon atoms, the NHR ₇ and NHR ₈ radicals being bonded to core carbon atoms and not in ortho- or are peri-position on R ₆ , with aromatic dicarboxylic acid dihalides of the general formula

HaIOC-R ₉ -COHaI

'n of Hal is a halogen atom, and R ₉ is a divalent aromatic radical, the two radicals COHal not in ortho- or peri-position to R _9, have been prepared at temperatures of from -20 to 5O ⁰ C in inert organic solvents , heated to temperatures above 200C or in the presence of acidic compounds above 60 C ^u.

Another object of the invention is the use of the polybenzimidazoles obtained according to this claim as molded objects and coverings.

When reacting an aromatic triamine or tetramine, where one or both N-aryl-substituted secondary amino groups are bonded to a core carbon atom which is adjacent to a core carbon atom to which a primary amino group is bonded, with the aromatic dicarboxylic acid dihalide, these secondary amino groups do not react with the Carbonyl halide of the aromatic dicarboxylic acid dihalide, and therefore a substantially linear aromatic polyamideimine containing the secondary amino groups in their original form is formed. This is also the reason why this aromatic polyamideimine is soluble in numerous organic solvents. When s * using the reaction conditions mentioned in claim 1 to such aromatic Polyamidimine it is possible to introduce a Cyclodehydratisierungsumsetzung between the secondary amino groups and carbonamide groups. The thermally and chemically more stable polybenzimidazole is formed in the process.

The procedure according to the invention allows the degree of polymerization and the degree of cyclization to be as desired Wise and very easy to be regulated.

In the following the invention is described in detail in the following series; described below.

1. Aromatic triamines or tetramines.

2. Diamines.

3. Aromatic dicarboxylic acid dihalides.

4. Process for the preparation of the aromatic polvamidimine.

5. Structure and properties of the aromatic polyamide imines.

6. Process according to the invention for the preparation of the polybenzimidazoles from the aromatic pol> amidimines and properties of the polybenzimidazoles.

1. Aromatic triamines or tetramines

2,4'-diaminodiphenylamine, 2,3'-diaminodiphenylamine, 4-methyl-2,4'-diaminodiphenylamine, 4-methyl-2,3'-diaminodiphenylamine, 4 methoxycarbonyl ^^ '- diaminodiphenylamine, 4-methoxycarbonyl-2,3'-diaminodiphenylamine, 4-phenoxycarbonyl-2,3'-diaminodiphenylamine, 4-methoxy-2,4'-diaminodiphenylamine, l- (2-aminoanilino) -5-amino-naphthalene, l- (2-aminoanilino) -4-amino-naphthalene, N- (2-aminophenyl) -benzidine, N- (4-methoxycarbonyl-2-aminophenyl) -benzidine, 4- (2-aminoanilino) -4'-amino-diphenyl ether, 4- (4-methoxycarbonyl-2-amino-anilino) -4'-amino-diphenyl ether,

3- (2-aminoanilino) -3'-amino-diphenyl ether, 4- (2-aminoanilino) -4'-amino-diphenyl sulfone, 4- (4-methoxycarbonyl-2-aminoanilino) -4'-amino-diphenyl sulfone, 3 - (? - Aminoanilino) -3'-amino-diphenylsulfone, 4- (2-aminoanilino) -4'-amino-benzophenone, 4- (2-Aminoanilino) -4'-amino-diphenylmethane, N, N'-bis (2-amiiK> phenyl) -p-phenylenediamine, N, N'-bis (2-aminophenyl) -m-phenylenediamine, N, N'-bis (4-methyl-2-aminophenyl) -p-phenylenediamine,

N, N'-bis (4-methoxycarbonyl-2-aminophenyl) -m-phenylenediamine,

N, N'-bis (4-methoxy-2-aminophenyl) -p-phenylenediamine,

N- (4-methoxycarbonyl-2-aminophenyl) -N '(2-aminophenyl) -p-phenylene-diamine, N, N'-bis (4-methoxycarbonyl-2-aminophenyl) -p-phenylenediamine,

l, 5-bis (2-aminoanilino) -naphthalene, N, N'-bis (2-aminophenyl) -benzidine, 4,4'-bis (2-aminoanilino) diphenyl ether, 3,3'-3is (2-aminoanilino) diphenyl ether, 4,4'-bis (2-aminoanilino) diphenyl sulfone, 3,3'-bis (2-aminoanilino) -diphenylsulfone, 4,4'-bis (4-methoxycarbonyl-2-aminoanilino) -diphenylsulfone,

4,4'-bis (2-aminoanilino) -benzophenone, 4,4'-bis (2-aminoanilino) -diphenylmethane, 2,2'-bis- [4- (2-aminoanilino) -phenyl] propane, 4 '-Methyl-2,3'-diaminodiphenylamine,2'-methyl-2,5'-diaminodiphenylamine,2'-methyl-2,4'-diaminodiphenylamine,2'-methoxy-2,4'-diaminodiphenylamine, N- (2 -Aminophenyl) -3,3'-dimethylbenzidine, N, N'-bis (2-aminophenyl) -2-methyl-p-phenylenediamine,
N.N'-bis (2-aminophenyl) -4-methyl-m-phenylenediamine,

N, N'-bis (2-aminophenyl) -3,3'-dimethylbenzidine, N, N'-bis (2-aminophenyl) -3,3'-dimethoxybenzidine.

2. Diamines

The reaction of the aromatic triamine or aromatic tetramine with the aromatic

17 95

Dicarboxylic acid halide obtainable aromatic Polyamide imines can be modified by adding 50 mole percent or less of the aromatic triamines or tetramines can be replaced by one of the diamines listed below. Will the aromatic Polyamidimine modified in this way with a diamine, the resulting modified Polyamidimine and the polybenzimidazole obtainable by its cyclodehydration have improved mechanical properties Properties such as strength, flexibility and elongation, although not related to the thermal resistance are particularly improved.

Among such aromatic diamines, compounds are particularly preferred in which R _{6 is} a phenylene group, biphenylene group, naphthalene group or

means, in which B 'is an alkylene group with 1 to 3 carbon atoms,

—O—, —s—. —So ₂ -

Il —C—

is, R ₇ and R _{8 are} identical or different and represent a hydrogen atom or a methyl group.

Aliphatic diamines and thus alicyclic diamines can also be used. The usable Aliphatic diamines have a structure in which two amine groups are represented by at least 3 carbon atoms are separated from each other, and should preferably have 3 to 10 carbon atoms in total.

Examples of the diamines that act as modifiers The following compounds can be used:

m-phenylenediamine,

4-methyl-m-phenylenediamine,

3-ethyl-m-phenylenediamine,

4-chloro-m-phenylenediamine,

4,6-dimethyl-m-phenylenediamine,

p-phenylenediamine,

N-methyl-p-phenylenediamine,

Benzidine,

3,3'-dimethylbenzidine,

3,3'-dichlorobenzidine,

3,3'-dimethoxybenzidine,

2,2-bis (4-aminophenyl) -pror> an,

4,4'-diaminodiphenylmethane,

S ^ '- DichloM ^' - diaminodiphenylmethane,

Bis (4-N-methylaminophenyl) methane,

4,4'-diaminodiphenyl ether.

4,4'-diaminodiphenyl sulphide,

4,4'-diaminodipheny! Su! Fon,

3,3'-diaminodiphenyl isulfone,

4,4'-diamiiiobenzophenone.

3,3'-diaminobenzophenone,

1,5-diaminonaphthalene,

4,4'-diaminodicyclohexyl methane.

l ^ -BisiaminomethyO-cyclohexane,

Hexamethylenediamine.

Nonamethylene diamine.

The applied diamines and aromatic triamines or tetramines can be used in the reaction with the dihalides of the aromatic compounds listed below Dicarboxylic acids either in the form of free bases or in the customary manner in the form of inorganic ones or organic acid salts are used, which do not interfere with the conversion to the formation of the Polyamidimine occurs according to the invention. In case the diamines and aromatic triamines or tetramines

ίο are used in the form of salts, their hydrochlorides, sulfates and toluenesulfonates, for example, are preferred, while the carboxylates should not be used. However, since larger amounts of acid acceptors have to be used during the reaction in the case of using the acid salts than in the case of using the free bases, it is generally more favorable to use them in the form of free bases, except for these diamines, triamines and SaUs Tetramines can only be isolated in the form of the acid salts.

3. Aromatic dicarboxylic acid dihalides

Terephthaloyl dichloride,
Isophthaloyl dichloride,
5-chloro-isophthaloyl dichloride,
2-chloro-terephthaloyl dichloride,
2,5-dichloroterephthaloyl dichloride,
Tetrachloro-terephthaloyl dichloride,
4,4'-dibenzoyl dichloride,
3,3'-dibenzoyl dichloride,
4,4'-sulfonyldibenzoyldichloride,
3,3'-sulfonyldibenzoyldichloride,
4,4'-oxydibenzoyl dichloride,
3,3'-oxydibenzoyl dichloride,
3,4'-oxydibenzoyl dichloride,
4,4'-benzophenonedicarbonyl chloride,
3,3'-benzophenonedicarbonyl chloride,
Diphenylmethane ^ '- dicarbonylchloride,
Diphenylmethane-S ^ '- dicarbonylchloride,
2,2-bis (p-chlorocarbonylphenyl) propane,

blWhl

carbonylphenyl) indane,
Naphthalene- ^ o-dicarbonyl chloride,
Naphthalene-2,7-dicarbonyl chloride,
Naphthalene-IS-dicarbonyl chloride.

4. Process conditions in manufacture
the aromatic polyamide imines

Any inert organic solvent can be used as long as there is at least one, and preferably both reactants, aromatic triamine or tetramine and aromatic dicarboxylic acid dihalide dissolves and dissolves or at least swells a polymer to such an extent that it partially does formed polymers is kept in the active state until the reaction is complete and that yields desired high molecular weight polymers. "Inert" is understood to mean that the solvent is practically unreactive in the reaction to form the polyamidimines.

Examples of conversion processes that can be used in the context of the invention are the following:

(1) A method in which the reaction in the presence an organic acid acptors carried out under practically anhydrous conditions will, and

(2) a method wherein the reaction is carried out in the presence of an aqueous solution of an acid acceptor is carried out.

In the polymerization reaction (1) under practically anhydrous conditions, both a inert organic solvent! as well as an organic acid acceptor used when the inert organic solvents themselves have no ability as acid acceptors (a); or if the inert organic Solvent itself has an acid acceptor ability, it also acts as an acid acceptor (b). In the case of (a), the inert organic solvent should dissolve the organic acid acceptor. As inert Organic solvents of this type are the following compounds as examples: halogen-substituted non-aromatic hydrocarbons in which at least one hydrogen atom is attached to the Halogen atom is bonded carbon atom, for example chloroform, methylene chloride, 1,1,2-trichloroethane, 1,2-dicloroethane, chlorobromomethane, s-tetrachloroethane and cis-l ^ -dichloroethane, furthermore cyclic methylene sulfones, such as. B. tetramethylene sulfone and 2,4-dimethyltetramethylene sulfone, methyl ethyl ketone, tetrahydrofuran, acetonitrile, propionitrile, Diethyl cyanamide, dimethyl cyanamide and mixtures thereof, with tetrahydrofuran being particularly suitable is.

Each compound is a common organic acid acceptor in the inert organic solvent can be used if they are used to react with the acid (hydrogen halide) formed during the polymerization reaction is capable and is a basic substance that has a stronger tendency to react with the Acid (hydrogen halide) has as reactants with the aromatic triamines or tetramines and which practically do not react with the aromatic Dicarboxylic acid dihalide, which is one of the reactants of the invention, reacts. Such basic substances (acid acceptors) include organic tertiary amines, such as trimethylamine, Triethylamine, N-ethylpiperidine, N-methylmorpholine, N-ethylmorpholine, Ν, Ν-dimethylbenzylamine and Ν, Ν-diethylbenzylamine, and polyfunctional tertiary amines, such as. B. Ν, Ν, Ν ', Ν'-tetramethyihexamethylene diamine.

The inert organic solvent that also acts as an acid acceptor (b) is organic Mentioned compounds of the amide type, such as. B. Ν, Ν-dimethylacetamide, Ν, Ν-diethylacetamide, Ν, Ν-dimethylpropionamide, Ν, Ν-dimethylbutyramide, l-Mothyl-2-pyrrolidone, l.S-Dimethyl ^ -pyrroIidon, l-ethyl-2-pyrrolidone, Ν, Ν, Ν ', Ν'-tetramethylurea, N-acetylpyrrolidine and hexamethylphosphoramide and mixtures thereof. If these solvents have insufficient acid acceptability, so can sometimes other acid acceptors, such as. B. tert. organic amines, as mentioned above, continue to be added.

Better results are sometimes obtained if one is added to the organic solvent a small amount of alkali or alkaline earth is added, for example lithium chloride, lithium bromide or calcium chloride.

If the polymerization is carried out in the presence of an aqueous solution of an acid acceptor, it is necessary to use an inert organic solvent, some of which is water is miscible. Examples of such inert liquid media are cyclic, non-aromatic, oxygen-containing, organic solvents, for example cyclic sulphones such as cyclic tetramelhylenesulphone and cyclic 2,4-dimethyl tetramethylene sulfone, cyclic ketones such as cyclohexanone and cyclopentanone, and cyclic ethers such as tetrahydrofuran and propylene oxide, lower aliphatic ketones such as methyl ethyl ketone and acetone, and mixtures thereof.

ίο Furthermore, in the case of the polycondensation reaction of type (2) a suitable neutral salt is added to the aqueous phase in addition to the acid acceptor in order to ensure the miscibility of the inert organic liquid medium with water in the usual way restrict. Suitable acid acceptors and neutral salts are the following:

Hydroxides of alkali metals, such as lithium hydroxide, sodium hydroxide and potassium hydroxide, and carbonates or bicarbonates of alkali metals, such as sodium carbonate and sodium bicarbonate, are preferred. Hydroxides, carbonates or bicarbonates of alkaline earth metals such as magnesium hydroxide, magnesium carbonate and calcium bicarbonate can also be used either alone or, if necessary, together with carbonates or bicarbonates of alkali metals. It is also possible to use water-soluble, organic, tertiary amines, such as. B. triethylamine to use.
It is preferred that these acid formulations be used in sufficient amounts to react with all of the acid (hydrogen halide) formed by the reaction.

As neutral salts are inorganic salts with great solubility in water, which with the reactants are not reactive. Alkali halides are preferred, such as. B. Sodium Chloride, Potassium chloride and lithium chloride. The sulfates and nitrates of the metals can also be used, however, it is preferred to use the same salt

4ü apply like the one formed by the implementation will. The use of such a neutral salt is particularly effective when such a reaction medium, such as acetone, which has very high hydrophilic properties, is used, and it is possible in this way a polymer with a higher molecular weight than in the absence of the neutral one Of salt.

The reaction conditions are described below.

According to the polycondensation process (1) a solution is prepared by adding the aromatic triamine or tetramine and, if necessary, the Acid acceptor and / or other additives are added. The aromatic triamine or tetramine can be used in the form of its acid salt if necessary. In this case, the acid salt should converted into the free base form in the solution by adding a calculated amount of an acid acceptor will. The solution is cooled to 0 to -20 ° C, and the dicarboxylic acid halogen itself or in the form of a solution in the reaction medium is added to the cooled solution; .. Da? The reaction mixture is stirred until the polycondensation has ended. The reaction temperature is in Range from 0 to 50 ° C. The time required to complete the reaction varies depending on the kind of the starting materials, the kind of the reaction solvent and the reaction temperature,

639 619/93

ψ)

10

but is usually between 0.5 and 8 hours. Bei dor vnrli ^^ ^, r c ι i

The polymer is separated off by the reaction * - a molecule rue S Ie ^hrlinuu ^. ^hin % & ^{n w} ! "

solution ζ, can be used for shaping purposes _e byjSm Ϊ 5 «ST", N, ^ TT "^ · '

The polycondensation process (2) is in ty- Uschs 5 Merk, ^ ^ one of the charak er, -

pischc. Manner carried out by adding a solution as flavoring according to the invention Dicarboxylic acid halide (C) in a Hei, w

if there is an emulsifier or a neutral salt, _c h ZTZ JP. V '"?""^ ^letran , ^im ? ■ '

and the _tS mixture is stirred rapidly The aronrt chin R r polycondensation under the same

tables rriamin or TetramS, (A) can be used in Pom s '* We ^ SSenT ΤΐΤί ^ ™ " ^wW · Säuresilzes if necessary In ₇ Z in h,".!, "- ^{bci der p} °'yl«> ndensal.onsumsel In this case the acid must be transferred to the free B ^ eniorm ^ Mo £ Sl T ⁸⁶ _p ^ ^itlcl . ^Z " ^r . ^Re fi ^ulicr _ri ^une m the solution by adding a calculated amount of reactio, ssv Z of the polyamidini.nc to be converted to that of the acid receptor. The implementation ₂₀ This ReS ^ ^ T "^" ^ADDING ^ '^ f is preferably at a temperature not high? tiönelle Z? Γ ^ ™ ^prefer e ^l ™ → ^ - executed as 50 X and is usually within BA _n ? Tf / ^{"1" U 16 "d Carbo">} · ^{lchloride such} as finished 15 minutes. The polymer is üb Ren ,, I, '"' P ^Chloranili" 'm-chloroaniline, licherw.ise powdered preserved and LAES skh easily obtain SZ S 'P-Toluoylchloride and p- or by filtration ^ nlorbenzoylchlond. Any number of mono-The polycondensation process (2) can be reduced to * ⁵ ITJr? r ^aromatic compounds used two ways to run. One route is the O, rhnnvih ° Γ " ⁵ ^ ^e " ^{1C primary} amino group above or typical procedures listed. The other we _R be ^ "^ 'halogen group with the same size is that a solution of the aromatic tri."" ^IOn . ^slah 'S ^{kcit again those of the primary} aminoamine or tetramine in the inert organic _3o or "Sc' C ^ Tf ™ ^Τ ί" ™ ⁰ ^ ^ "T solvent with a solution of the aromatic carhnn,! ,, S. ^ya - ° ^{8enids DCS mimatischen Dl} ". Dicarbdnsäuredihalogenids in e nem inert Orca ^{c dr} oonsduredihalogenids have beabsichnischen and the solvent are mixed and thereby a hind ^{densatlonsuiriSetzun} g virtually impossible beLösung or dispersion of a reactive oligo-""'

kidneys are formed and then these with an aqueous 35 ⁵ · Aromatic Polyamidine

Solution of the acid acceptor brought into contact If H ,. di

is to end the polycondensation -. ^cnds ' olyamidimine with the aromatic There is hardly any difference "with regard to the-DTt" ⁶ "" ^{is iodified soi1} · ^ Hs triamine properties and the degree of polymerization between the content of structural units with the aromatic polyamideimines after _Λο ^ Mi ° ^{Dlam |} NEN preferably are not available as these two processes more ¹ ^ "^'andf" s tetramines be used' This u- ^{pr0Eent the} total structural units that when erfindunesgemäßen method .. beer are located 'is intended to aromatic triamine or tetramine and aromatic ^"V t " ^{Preferably not} more than 40 mole percent. Dicarbv'jisäurehalogenid in the inert organic tk hd? Are reacted ^{advantages cier since} in the obtained aromatic liquid medium, even if, ^{nc "Po} 'yamidimine are following aufceführt: aqueous solution of acid acceptor is used α ^{Since the} N-aryl-substituted secondary amino, since the aromatic triamines or tetramines ent h" ^ΡΡ £ ΐ is ^{Se 'BSL reaklionsf} äriig, at a position speaking the invention difficult _r soluble in water _ ^e | ^1achbart present ^to a primary amino group are, they move little in an aqueous phase ^self-S? I ^{do d 'C Venvendu} ng of aromatic Triwenn its solution in an inert organic Lö so Pi "° ■? ^{Tetramine to} form aromatic sungsmmel with a aqueous solution of the acid ^ ₁ 7 ^{a, m dlmid 'dle in N>'} - dialkyl, and cyclic mixed acceptor These facts demonstrate NC η ^{'such as "B"} Ν, Ν-dimethylacetamide, that the · reaction according to the!. Invention for education. ^ '^ ^Lme t ^h y ^If orrnamid and l-Methyi-2-pyrrolydon of an aromatic polyamidine from an aroma ^ I ^S ' i ° ^{Ie aromatic} polyamidimines are tables triamine or tetramine and an aroma <- a '" J ^etrameth y ^lharn material, Hexamethylphosphortischen dicarboxylic acid dihalide in all facial T α dimethyl sulfoxide, as well as in amides, for r points significantly from the known interfaces, such as are ^pieIe acetamide and cyclic amides polycondensation of aromatic diamines and orsa ^La ^ P ^rol actam, which is different usually at Raummscher dicarboxylic acid dihalides ^m ^ P ^{erature f} est are at temperatures above the In the known Grenzflächenpolykondensations' 60 P, P ^unktes this solution ^melz soluble. Some of the methods will use the aromatic diamine at a ™>^am; ^dlr nine are in phenols, such as m-cresol and interfacial transition from an aqueous to the Sä _u ™ n " ^l0Sl ' ^Ch ·

ikceptor dissolved containing phase in ^ the organic "mante heat-resistant polymers, such as. B.

Solvent phase polymerizes. Therefore vhd the ^{po |} Y ^heterocyclic compounds and full molecular weight of the polymer obtained in the wide range of 6, ^a '° ^matlsch , ^e polyamides usually show only one

Jmfang by such factors as Rührgeschwindiß ° ^eg f ^enzte solubility in organic solvents,

ceit of the reaction system, concentration of the reac ϊ, ϊ "^ ^{Γ £ extremely} difficult, stable solutions of

lonslösung and basicity of the acid acceptor stunning "TT ^Konzentra t'on of the polymers to produce.

s, Deem- On the other hand, the aromatic polyamide imines

according to the establishment in stable solutions of high Concentration can be transferred using the organic solvents listed above. Furthermore, these solutions can be mixed with other diluents, e.g. B. acetone, toluene. Cyclohexane. Benzene and methylene chloride can be diluted.

2. As a result, the aromatic polyamide-imides can be used as paints and varnishes will. These can be dissolved in the organic solvents listed above, or they can can be formed into brains, foils, fibers and other objects in a simple way.

3. The aromatic polyamide-imides can easily be replaced by further thermal and / or chemical Conversion of treatment into thermally and chemically stable N-aromatic-substituted polybenzimidazoles. The one with it The resulting polybenzimidazoles are usually soluble in suitable organic solvents.

6. In accordance with the invention method of manufacture
of N-aryl-substituted polybenzimidazoles

The aromatic polyamide-imides can be converted into N-aryl-substituted polybenzimidazoles, by heating them to a temperature above 200 C but below a temperature value which the decomposition of the polybenzimidazole obtained takes place to such an extent that substantial Damage caused. In general, however, it is preferred that the reaction at a Temperature of 200 to 600 C, in particular 250 to 500 C, is carried out. If an acidic substance simultaneously with the cyclodehydrationumseu, mg is used, the heating temperature is above 60 C: but it must be below a temperature at which the above-mentioned polybenzimidazole decomposes to such an extent that Disadvantages occur! In general, there is a temperature between 60 and 200 ° C, especially 80 and 200 ° C. suitable.

Those acidic substances are particularly preferred which absorb the water formed during the cyclodehydration reaction, d. H. one Have dehydrating effects. Examples are inorganic and organic acids such as hydrochloric acid, Phosphoric acid, polyphosphoric acid, p-toluenesulfonic acid, Oxalic acid, formic acid, dichloroacetic acid, triPoroacetic acid. The amount of to be added acidic substance can be about 0.001 to 15 percent by weight, based on polyamidimine, where however, the upper limit is not necessarily limited to 15% by weight.

The cyclodehydration to convert the Polyamidimines according to the invention in polybenzimidazoles can be effectively carried out when the reaction system contains the above-mentioned acidic substance and an organic solvent which can swell, and in particular both the polyamideimine and the polybenzimidazole can dissolve.

In practice, the cyclodehydration according to the invention can be carried out in the following manner will:

The Poiyamidirnine can undergo thermal cyclodehydration in the form of powders, flakes, irregularly broken particles or from the polyamideimine solutions shaped solids, such as B. films, foils, fibers, coatings and other shaped Be subject to circumstances. As a heating medium

Both a liquid wedge and a gas can be used as long as they are inert to the aromatic polyamide-imides and do not dissolve them. In general air, inert gases such as nitrogen and carbon dioxide gas, liquid media such as Heat transfer fluids and silicones.

If one wishes to dissolve the polybenzimidazole obtained in an organic solvent, it will preferred that the Würmecydisicrung in air-free Conditions is carried out, for example in an inert gas or under vacuum. It is also possible, the aromatic polyamideimine in the form of its solution in an organic solvent cyclodchydratisicren and thereby to be converted into a polybenzimidazole. In this case the application an acidic catalyst is preferred. For example, a solution of the polybenzimidazole if a solvent is used for both the aromatic pohamidimine as well as polybenzimidazole is applied and a small amount of an acidic catalyst, such as hydrochloric acid or p-ToluoI-sulfoiis-iure is added and at a temperature above 60 C, preferably at a temperature im Range of 80 C up to this point the solvent is heated.

If it is still a solid aromatic polyamidimine or a solution of the same in an inert organic solvent to such an acidic one Solvents such as formic acid, dichloroacetic acid and trfluoroacetic acid. wherein the polybenzimidazole of the invention is soluble. is added and the mixture is heated and cyclodehydrated, the obtained polybenzimidazole gradually in the acidic solvent in the course of the cyclodehydration reaction dissolved, and the polybenzimidazole can be obtained in the form of the solution. When the cyclodehydration reaction Performed in solution consists of that as a by-product Water formed has a tendency to initiate hydrolysis of the polyamideimine. It is therefore preferred that the heating conditions for the cyclodehydration reaction are relatively mild.

According to the invention, a molded article of a suitable cyclized polybenzimidazole can be obtained be, which one a solution of the aromatic polyamidimine during their formation, for example Forming into foils, after the casting process is heated, and after shaping can the molded article can be further subjected to cyclodehydration. Of course, the Cyclodehydration reaction can be promoted by adding a suitable acidic substance.

The N-aryl-substituted polybenzimidazoles produced by the process of the invention have excellent heat resistance when used for a long time at 200 ° C, for example resistant, have a good resistance to oxidizing atmospheres and are stable to various chemicals such as acids or alkalis, unc can be formed into objects with excellent mechanical and electrical properties. Molded articles made from these polybenzimidazoles are useful as coatings, films, fibers and other everyday objects.

Most of the N-aryl-substituted polybenzene produced by the inventive method imidazoles are soluble in formic acid or dichloroacetic acid. Some of them are even in m-cresol

Dimethyl sulfoxide, N-methyl-2-pyrrolidone or Ν, Ν-Dimethylacetamide soluble. Furthermore I mclzcn some of them above 300 C. From for this reason they can easily be deformed into a wide variety of objects.

The structures of the aromatic polyamidimines and the N-aryl-substituted polybenzimidazoles, the represented by the above general formulas were determined by elemental analysis or Infrared absorption spectra confirmed as given in the examples below.

The invention is explained in more detail below by means of examples, some of the examples Polyamidimines relates to those in the invention Process polybenzimidazoles are produced.

In the examples, the intrinsic viscosities (// _{i! Lh} ) are measured at 30 C and which are measured according to the following formula

/, inh =

In I ₁ rei

were determined.

The relative viscosity (// _r , i) can be determined by dividing the flow time in Ostwald viscometers of a dilute solution of the polishing agent by the flow time for the pure solvent. In the above formula, C denotes the polymer concentration, given as the number of grams of the polymer weight in 100 ml of solvent.

Unless otherwise stated, the inherent viscosities listed in the examples were obtained with dimethylformamide solutions of the polymers determined at a concentration of 0.5 g / 100 ml.

The thermogravimetric analyzes were with an extent of the temperature increase son 5 C min carried out in air.

example 1
A. Preparation of the polyamideimine

A solution consisting of 2.72 g (0.01 mol) of Z ^ '- diaminodiphenylamine'ii hydrochloride. 4.24 g (0.04 mol) of sodium carbonate, 50 ml of water and 42 ml of tetrahydrofuran were placed in a vortex mixer and shaken vigorously. To the resulting mixture, a solution consisting of 2.03 g (0.01 mol) of terephthaloyl chloride and 17 ml of tetrahydrofuran was added and reacted by continuing the shaking for 10 minutes. The reaction was carried out at room temperature, and towards the end of the reaction, precipitation of a polymer was completed by adding a large amount of water. After filtering. Washing and drying gave a yellow powdery polymer almost quantitatively. It was found that this polymer possessed an egg viscosity of 0.77 and in an organic solvent, such as. B. Dimeth ^ 'lformamide, N. ^ I-DimethvI-acetamid, N-methyl-2-pyrrolidone and dimethyl sulfoxide, was soluble in large concentrations. A tough yellow clear film could be formed from such a solution. It was observed that the polymer did not soften below a temperature of 350 ° C. on a hot plate. Thermo-gravimetric analysis of the polymer showed a weight loss by cyclodehydration at a temperature in the vicinity of 250 C, but thereafter it showed almost no weight loss up to a temperature of 430 C and even maintained at a temperature of 550 "76" , ', of the initial weight ¹ at.

The infrared absorption bands became at 3300cm ίο due to the - NH group and at 1650 cm 'unc 1510 to 1530 cm 'due to the

—CNH group

observed. The elemental analysis yields values for C: 70.95 ",,, H: 5.21 'J ₁₁ and N: 12.15" ,,, which essentially agrees with the calculated values (C: 72.93 ",,. H: 4, 59%, N: 12.76 ",,). It could be confirmed from these data that the polymer obtained has a polyamidimine structure.

B. Preparation of the polybenzimidazole

This polymer in powder form was at 300 ° C. for 6 hours under reduced pressure heated to cyclodehydrate it. After this treatment, the polymer hardly changed external appearance, with the exception of a slight fading of the color. The resulting cyclized The polymer had an inherent viscosity of 0.63. measured in a sulfuric acid solution. It was insoluble in solvents of amide glyph and in dimethyl sulfoxide, but soluble in formic acid, dichloroacetic acid and m-cresol. A solution of the polymer in such a solvent produces a film.

According to the infrared absorption spectrum, a characteristic absorption of the amide moiety was weakened, and a characteristic absorption of the N-aryl-substituted benzimidazole showed strong absorption ^{even at 1380 cm -1.} To find out the degree of cyclization, the polyamideimine was dissolved in 116 "" polyphosphoric acid and heated to prepare a standard sample of the polyamide benzimidazole which was considered fully cyclized as described in Example 45. The polyamide benzimidazole according to the present example and the standard sample according to Examples 45 were compared on the basis of their infrared absorption spectrum and found to be in good agreement with each other in terms of their absorption bands and their relative intensities, and it was found that the cyclization of the polyamidimine by heating under the conditions of the present example was almost complete The thermogravimetric analysis of the cyclized polymer revealed that there was no weight loss by cyclodehydration at a temperature in the vicinity of 250 ° C, which was observed with the polyamideimine before cyclization, and there was hardly any weight t loss up to 430 ^c C, and

even at 690 C ⁼ 70% of the initial weight are retained. This is an indication of the excellent thermal stability of the polyamide benzimidazole obtained above.

ϊ 7 95

Example 2 (polyamidimine)

In a 100 ml, three-necked flask fitted with an air-tight stirrer and a calcium chloride tube, 2.72 g (0.01 mol) were added. 2,4'-dian; inodiphenylamine dihydrochloride suspended in 25 ml of N-methyl-2-pyrrolidone. whereupon 2.02 g (0.02 mol) of triethylamine was added. While the resulting mixture was being cooled with ice from the outside, 2.03 g (0.01 mol) of terephthaloyl chloride was added with stirring. The system was ice-cooled until the exotherm in the initial stage of the reaction subsided, and then the reaction was continued at room temperature. After a total reaction time of 5 hours, the converted solution was transferred to water and a polymer separated off. The separated polymer was washed thoroughly with a dilute aqueous solution of sodium carbonate, exchanged with water and methanol ions, and dried under reduced pressure. A yellow polymer was obtained quantitatively which had an inherent viscosity of 0.29. The infrared absorption spectrum. the solubility and the thermal properties of the polymer obtained correspond to the polymer obtained in Example 1.

Example 3 (polyamidimine)

^I: s was repeated according to Example 1, except that isophthaloyl chloride was used in place of Therephthaloylchlorid the operation. A light yellow polymer with an inherent viscosity of 0.69 was obtained almost quantitatively. The polymer obtained was in a polar organic solvent, such as. B. Dimethylformamide, Ν, Ν-Dimcthylacetamid, N-methyl-2-pyrrolidone and Dimethylsulfoxyd soluble in high concentration, and it could be obtained such a shaped object as a film from the solution of the polymer in such a solvent.

It was observed that the polymer non-softened on a hot plate at a temperature below 35O ⁰ C. The thermogravimetric analysis of the polymer showed a weight loss due to cyclodehydration at a temperature in the vicinity of 250 ° C., but beyond that it shows almost no weight loss up to a temperature of 420 ° C. The infrared absorption spectrum indicated that the characteristic absorptions of the polymer obtained agree well with those of the polymer according to Example 1, from which it can be concluded that it has a polyamidimine structure.

Example 4 (Polyamideimine)

In a 100 ml three-necked flask equipped with an airtight stirrer and a calcium chloride tube, 2.90 g (0.01 mol) of N, N'-bis (2-aminophenyl) -p-phenylenediamine in 20 ml of N-methyl-2-pyrrolidone dissolved with mixing and stirring. While the resulting solution was being cooled with ice from the outside, 2.07 g (0.0102 mol) of terephthaloyl chloride was added with stirring. The reaction system was cooled until the exothermic phenomenon at the beginning of the reaction subsided, and then the reaction was continued at room temperature. After a total reaction time of 5 hours, the reacted solution was added to water and a polymer separated out. The precipitated polymer was washed thoroughly with a dilute aqueous solution of sodium carbonate, exchanged with water and methanol and dried under reduced pressure. A yellowish-orange polymer was obtained quantitatively which had an inherent viscosity, measured in N-methyl-2-pyrrolidone solution, of 0.27. The polymer obtained was soluble in solvents such as Ν, Ν'-dimethylacetamide, N-methyl-2-pyrrolidone and dimethyl sulfoxide, and a film can be formed from a solution of the polymer in such a solvent. It was observed that the polymer on a

ίο The heating plate has not softened below a temperature of 35O ° C. The thermogravimetric analysis of the polymer showed that a weight loss mt cyclodehydration to? .U a temperature around 25O ^C C but thereafter it shows nearly no weight loss up to a temperature of 450 C. It has a strong, characteristic absorption of

Il

—CNH-

observed at 3300 cm ^-1 , 1660 cm ^-1 , 1510 to 1530 cm ^-1 and 1300 cm ^-1 in the infrared spectrum of the polymer, as with the polymer according to Example 1. In the elemental analysis, values were found for C: 72.52%, H: 5 , 10% and N: 13.03 "", which essentially corresponds in calculated values (C: 74.27%, H: 4.79%, N: 13.33%).

The polymer obtained, in irregularly ground or comminuted form, was heated for 4 hours at 32 ° C. under reduced pressure in order to cyclodehydrate it. A red-brown cyclized product was obtained which had an inherent viscosity in sulfur, acid solution of 0.23. The product was insoluble in amide type solvents but soluble in formic acid or dichloroacetic acid. It was possible to perform a dry molding of the polymer from its solution in such a solvent. It was found from the infrared absorption spectrum that some characteristic absorptions of the amide carbonyl remained in the vicinity of 1660 cm ", but the absorption of the amide II and III at 1530 cm ^-1 and 1300 cm" ¹ almost disappeared. On the other hand, a strong characteristic was revealed Absorption of the N-aryl-substituted benzimidazole at 1380 cm ', which indicates that the polymer had been converted into polybenzimidazo. The thermogravimetric analysis of the heat-treated polymer showed that there was no weight loss due to cyclodehydration, which occurred for the polyamideimine at a temperature of around 250.degree and above occurred, and that the polymer exhibited hardly any reduction in weight at a temperature up to 500 ° C. and that 70% of the initial weight

609 619/93

fio

were still present even at 640 "C. This is an indication for the excellent thermal stability.

Example 5
(Polyamideimine)

A solution consisting of 2.90 g (0.01 mol) of N, N'-bis (2-aminophenyl) -p-phenylenediamine, 2.12 g (0.02 mol) of sodium carbonate, 40 ml of tetrahydrofuran and 50 ml Water was placed in a vortex mixer and shaken vigorously, after which a solution consisting of 2.03 g (0.01 mol) of terephthaloyl chloride and 17 ml of tetrahydrofuran was added. The shaking was continued for 10 minutes to effect the reaction. The reaction was carried out at room temperature, and at the end of the reaction the precipitation of the polymer was completed by adding a large amount of water. Filtration, washing and drying gave a gel-orange polymer in almost quantitative yield. This polymer had an inherent viscosity; t ^: it of 0.38, measured in sulfuric acid solution to yar in dimethylsulfoxide, N-methyl-2-pyrrolido ·, \, N-dimethyldcetamide and dimethylformamide r.il. ; soluble in content of lithium chloride. The I lfr. infrared absorption spectrum, and the results dt 1 i thermogravimetric analysis of this polymer; were the same as those of the polyamidimine according to Example 4.

30 Example 6

(Polyamideimine)

The procedure of Example 2 was repeated with the modification that isophthaloyl chloride was added Instead of terephthaloyl chloride was used. It became a light yellow polymer almost quantitatively obtained which had an inherent viscosity of 0.47 in a concentrated sulfuric acid solution. The The polymer was in dimethyl sulfoxide, N-methyl-2-pyrrolidone, Ν, Ν-dimethylacetamide and dimethylformamide with a content of lithium chloride soluble, and shaped objects could be made from a solution of this polymer in these solvents getting produced.

The polymer obtained did not soften at a temperature below 350 ° C. The thermogravimetric Analysis of the polymer revealed that there was a remarkable weight loss due to cyclodehydration could be observed at a temperature in the vicinity of 250 C, but after that Almost no weight loss was observed at a temperature up to 480 C, which is excellent means thermal stability.

The infrared absorption spectrum of the polymer corresponds to that of the polyamidimine according to Example 4 with regard to the characteristic absorption of the Amide group, and it was observed that the polymerizate has a polyamidimine structure.

60

B eis ρ ie I e 7 to 11
(Polyamide imides)

The procedure according to Example 1 was used repeated, with the modification that a combination of triamine dihydrochloride and the dicarbonyl chloride as indicated in Table I, was replaced. Each example has been quantitative a powdery polymer which was light yellow to yellow was obtained. The inherent viscosity of each obtained Polymer is given in Table I. All the polymers obtained were in such solvents such as N-methylpyrrolidone Ν, Ν-dimethylacetamide, Dimethylformamide and dimethylsulfoxide were soluble and had an excellent (transforming Characteristic.

The infrared absorption spectrum of the polymer showed a strong characteristic absorption of the Amide group, and thermogravimetric analysis indicated that weight loss in one Temperature in the vicinity of 250 "C and above due to the cyclodehydration taking place. From this it can be concluded that the polymers obtained according to these examples have a polyamidimine structure exhibit.

table 1 Aromatic Own example Aromatic Dicarbonyl viscosity Triamine dihydro chloride of he chloride hold Poly merisats ('/ inh) 2,6-naphthalene 0.75 7th 2,4'-diamino dicarbonyl diphenylamine chloride Isocynchomero 0.61 8th 2,4'-diamino nyl chloride diphenylamine Terephthaloyl 0.58 9 4-methyl- chloride 2,4'-diamino diphenylamine Terephthaloyl 0.39 10 4'-methyl chloride 2,3'-diamino diphenylamine Terephthaloyl 0.48 11th l- (2-amino- chloride anilino) -4-ami- nonaphthalene Ie 12 to 22 B e i s ρ i e (Polyamide imines)

The procedures of Example 1 were repeated with the modification that parts of the 2,4'-diaminodtphenylamine dihydrochloride (2,4'-DADPA ■ 2 HCl) by other aromatic triamines or aromatic ones Diamines were replaced and parts of the terephthaloyl chloride were replaced by other aromatic dicarbonyl chlorides, as shown in Table 2 below. In each example it became a powdery Quantitatively obtained polymer with a color of light yellow-yellow. The inherent viscosity of each polymer is listed in Table 2. Each of the polymers did not soften below a temperature of 300 C, as could be seen on a hot plate. The solubility of each polymer was much more similar in comparison to the homopolymer according to Example 1, and it was in such Solvents such as N-methyl-2-pyrrolidoii, Ν, Ν-dimethylacetamide and dimethylformamide soluble. It could be a stretchable, tough film from a solution

of each polymer in such a solvent be shaped.

It was z. B. found that a film with a thickness of about 40 microns, which by drying

deformation from a solution of the polyamidimine in dimethylformamide, which was obtained according to 3example 13, had a strength of 620 kg / cm ² and an elongation of 12 ".

Table 2

example Amine component Comonomer i '.- V 4,4'-diaminodiphenyl ether (Mole) Acid chloride components (Mole) Own No. Amount of 4,4'-diaminodiphenylmethane 0.002 0.01 viscosity of the 2,4'-DADl 4,4'-DiaminodiphenyIsulfone 0.002 0.01 Polymer 2HCl 3,3'-Diaminodiphen \ Nulfone 0.0025 0.01 (MoI) m-phenylenediamine 0.004 0.0! ('/ inh) 12th 0008 p-phenylenediamine 0.002 Terephthaloyl chloride 0.01 1.05 13th 0.008 N-methyl-p-phenylenediamine 0.002 the same 0.01 0.89 14th 0.0075 1,5-diaminonaphthalene 0.001 desel. 0.01 0.67 15th 0.006 the same 0.002 the same 0.01 0.80 16 0.008 the same 0.008 0.75 17th 0.008 4-methoxycarbonyl- the same 0.002 0.84 18th 0.009 2,4'-diaminodipheny! Amine 0.002 the same 0.01 0.58 19th 0.008 4-methoxy-2,4'-diamino the same 0.73 20th 0.01 diphenylamine · 2HCl 0.002 Terephthaloyl chloride 0.01 0.71 Isophthaloyl chloride 21 0.008 Terephthalic oyl chloride 0.58 0.008 the same 0.49

Examples 23-30
(Polyamide imines)

In each example, 0.01 moles of the aromatic triamine or tetramine were shown as shown in Table 3, with 0.01 mol of the aromatic dicaibonyl dichloride in N-methylpyrrolidone (N - MP) in agreement reacted with procedures according to Example 4, a polyamideimine being obtained. For example when using a hydrochloride, an amine as a starting material, triethylamine was in a Amount equimolar to the hydrochloric acid content in the amine was, the reaction in the form of a solution in N-methylpyrrolidone, as described in Example 2, added. The amount of N-methylpyrrolidone used and the inherent viscosity of each polymer is shown in Table 3 below. All the polymers obtained were in such Solvents such as N-methylpyrrolidone, Ν, Ν-dimethylacetamide, dimethylformamide and dimethylsulfoxide soluble, and molded articles such as B. a film from the solutions of the Polymers produced in these solvents. It was observed that that obtained in Example 28 was obtained Polymer on a hot plate had a softening point of 320 to 340 "C and that the The polymer obtained according to Example 30 had a softening point of 270 to 290.degree. Other Polymers showed no clear softening point at a temperature below 350 C.

Table 3 example

Amine component

Acid Chloride Component

Amount of N-MP

(ml)

Inherent viscosity of the polymer

dl Inh)

23 2,4'-Diaminodiphenylamine · 2HCl

24 the same.

25 N, N'-bis (2-aminophenyl) benzidine

26 N- (2-aminophenyl) benzidine

27 1,5-bis (2-aminoaniline) naphthalene

28 4,4'-bis (2-aminoaniline) diphenyl sulfone

29 4 "(2-aminoanilino) -4'-aminodiphenyl sulfone

30 4,4'-bis (2-aminoanilino) -diphenyiälh; r de ^ gl.

4,4'-dibenzoyl chloride 20th 0.29 4,4'-sulfonyldibenzoyl chloride 20th 0.31 Terephthaloylchloriii 30th 0.65 the same 30th 0.71 the same 30th 0.46 the same 25th 0.55 the same 25th 0.59

0.58

B is ρ ie 1 e 31 to
(Polyamide imines)

39

The working methods according to the example! 4 were repeated with the change that part of the aroi.id table Triamine or aromatic tetramine by aromatic diamine or aliphatic diamine such as shown in Table 4, and replaced part of the terephthaloyl chloride with isophthaloyl chloride would. When using a hydrochloride,

an amine as the starting material was triethylamine in an amount which was equimolar to the hydrochloric acid content in the amine, the reaction in Ft.rm of a solution in N-methylpyrrolidone, as described in Example 2, added. The amount of N-methylpyrrolidone that was used and the inherent viscosities of those obtained Polymers are shown in Table 4 below. The polymers obtained with Except for the polymer that had been obtained according to Example 32, N-methylpyrrolidone, Dimethylformamide, Ν, Ν-dimethylacctamide and dimethyl sulfoxide soluble. The polymer according to Example 32 was only soluble in N-methylpyrrolidone. It molded articles such as B. a film of solutions of these polymers in such solvents getting produced.

Table 4

When implementing 0.02 moles of terephthaloyl chloride with 0.005 mol of N, N'-bis (2-aminophcry '|) -p-phenylenediamine and 0.015 mol of 4,4'-diaminodiphenyl ether in N-methylpyrrolidone, a polymer with an intrinsic viscosity (measured at 30 C, 0.5 2.100 ml polymer concentration in concentrated Sulfuric acid) of 0.95, which was insoluble in an Omani solvent and only in Sulfuric acid was soluble.

It was observed that the polymer obtained according to Example 38 had a softening point on a hot plate from 325 to 340 C and the polymer obtained according to Example 39 has a softening point from 315 to 330 C. All other polymers obtained showed no clear softening point at a temperature below 350 C.

Example amine componentsc

Amount of triamine

or tetramine

Comonomer acid chloride component c

(Mole)

(Garbage

Amount higen-

iin viscosity of

N - MC polymer

(Mol) (ml) (i / inh)

N, N'-bis- (2-amino-0.015 4,4-diamino-0.005 terephthaloylphenyl) -p-phenylcn- diphenyl chloride

diamine

the same
the same

the same

the same
the same
the same

2,4'-diaminodiphenylamine
dihydrochloride

the same

0.010 the same

0.015 like

0.010 descl.

0.010 the same.

0.005

0.010

0.01 4,4'-diamino-0.005 diphenylmethane tercphthaloyl chloride
Isophthaloyl chloride

Terephthaloyl chloride
isophthaloyl chloride

Terephthaloyl chloride

0.01 3,3'-diamino-0.005 like diphenyl sulfone

0.008 1,5-naphthalene-0.002 like diamine

0.016 4,4'-diamino-0.004 like dicyclohexylmethane

0.016 hexamethylene 0.004 like diamine

0.02 40

0.02 40

0.015 40 0.005

0.015 40 0.005

0.015 30

0.015 30

0.01 20

0.02 60

0.02 50

0.59

0.80 conc. 0.45

0.60

0.65 0.60 0.43 0.40

0.28

Example 40
(Polybenzimidazole)

It became a tough yellow film by a dry method from a solution of the polyamideimine obtained according to Example 1 in N-methyl-2-pyrrolidone. The film was for 5 hours at 300 C below, heated under reduced pressure to cyclodehydrate it. The film retained its elasticity, and along with it except that the color faded a little, there was no change in its external appearance perceived. According to the infrared absorption spectrum, the characteristic absorption decreased of the amide group, and the characteristic absorption of the N-aryl-substituted benzimidazole at 1380 cm 'came out clearly. By comparison the relative intensity of the characteristic absorption as in Example 1, it was found that the relative intensity of the characteristic absorption of the film according to the present example almost completely corresponds to that of the standard sample. From this it can be concluded that the film is almost completely converted into polyamibenzimidazole

Was 60.

Example 41

(Polybenzimidazole)

The polyamideimine obtained according to Example 3 was pulverized for 6 hours at 310.degree heated to cyclodehydrate it. There was almost no change in the external appearance of the treated polymer perceived. The poly

mcrisat only swelled in amide-type solvents such as. B. dimethylacetamide and N-methyl-2-pyrrolydone and was insoluble in them. It was in such solvents as formic acid, dichloroacetic acid and sulfuric acid, almost entirely soluble, though it remained partially undissolved. The The polymer had an inherent viscosity in sulfuric acid of 0.29.

The infrared absorption spectrum indicated a strong absorption at 1380 cm "" ¹ , and it can be concluded that the polyamideimine had been converted to polyamide benzimidazole. The thermogravimetric analysis showed that hardly any weight loss takes place at a temperature of up to 420 ^° C. and that 70% of the initial ^{weight is still present even at 600 ° C.}

B is ρ ie! 42
(Polybenzimidazole)

A tough yellow film was obtained by a dry method from a solution of the polyimimine obtained in Example 3 in N-methylpyrrolidone. The film was heated under reduced pressure at 310 ° C. for 5 hours to cyclodehydrate it. The film became almost colorless, but there was no other change in appearance. The infrared absorption spectrum indicated the presence of a characteristic absorption of the Βεηζ-imidazole at 1380 cm " ¹ , to the same degree as Example 40, and it can be concluded that the film was almost completely converted to polyamide benzimidazole.

Example 43
(Polybenzimidazole)

The Polyamidimin Example 6 obtained as described was heated in powdered form for 4.5 hours at 33O ⁰ C to cyclodehydrating it. A purple cyclized polymer was obtained which was insoluble in solvents of the amide type but was soluble in formic acid. Shaped articles such as B. Films are made from the solution of the polymer in this solvent. The polymer had an inherent viscosity in sulfuric acid of 0.46. According to the thermogravimetric analysis, almost no weight loss occurred at a temperature up to 55CFC, indicating excellent thermal stability.

From the infrared absorption spectrum it can be concluded that the polyamideimine is almost complete in polybenzimidazole as in the case of Example 4 had been converted.

B: eis ρ ie 1 44
(Polybenzimidazole)

The polyamideimine (0.8 g) obtained according to Example 4 was heated in 20 g of polyphosphoric acid (total amount of P ₂ O ₅ = 84%) in a 50 ml three-necked flask equipped with a stirrer sealed against air and a calcium chloride tube , and the solution was further ^{heated for 2 hours at 120 °} C. with stirring. After the reaction had ended, the reactants mixture was transferred to approximately 0.5 l of cold water in order to deposit a polymer. After thorough washing with water and an aqueous solution of sodium carbonate, the polymer was filtered and dried. A red-violet cyclized polymer was obtained almost quantitatively. The obtained polymer swelled and was insoluble in the above-mentioned amide-type solvents, but was soluble in formic acid and dichloroacetic acid. Shaped articles such as B. a film can be produced by means of a dry method from a solution of the polymer in a solvent such as this. The polymer had an intrinsic viscosity in formic acid of 0.40.

ίο According to the infrared absorption spectrum, a characteristic absorption of the amide group disappeared, and a characteristic absorption of the N-aryl-substituted benzimidazole at 1380 cm ^{& liter became} strongly apparent. From this fact, it could be confirmed that the polyamideimine was almost completely converted into polybenzimidazole. By measuring by means of a thermobalance was found that almost no weight loss is effected, and at a temperature of up to 500'C 70% of the initial weight are still present even at 640 ⁰ C, indicating excellent thermal stability.

Example 45 (Polybenzimidazole)

Ig of Polyamidimins obtained in Example 1 was reacted (= 84% total content of P ₂ O ₅₎ for 2 hours at 120 ⁰ C in 26 g PoIyphosphorsäure, wherein a light yellow Polyamidbenzimidazol was obtained. The polyamide benzimidazole obtained was soluble in formic acid, dichloroacetic acid and m-cresol, and molded articles could be produced from a solution of the polyamide benzimidazole in such a solvent. It had an intrinsic viscosity in formic acid of 0.53.

Since almost the same cyclization conditions as in Example 44 were used, it is assumed that that the polyamide benzimidazole obtained in the present example is complete has been cyclized. The infrared absorption spectrum of this polymer became the standard spectrum used to determine the degree of cyclization of the polyamide benzimidazoles obtained by other cyclization methods to determine.

Example 46 (Polybenzimidazole)

1.0 g of the polyamidimine obtained according to Example 1 were suspended in 10 ml of 99% strength formic acid and refluxed for 5 minutes with stirring. The polymer dissolved all gradually rose, and a homogeneous solution with a red-violet color was thus obtained. The homogeneous « Solution was poured onto a glass plate, and di <formic acid was evaporated, whereby a through more visible film received vmrde. The infrared absorption spectrum of the film corresponded well to that de polyamide benzimidazole obtained in Example 45, wa means that the conversion was complete. There The polyamide benzimidazole obtained in this way had a basic molar viscosity of 0.71 in formic acid. It has better solubility than a polyamide benzimidazc with the same repeating unit that is used in de the last half of Example 1 had been obtained by means of Hitzecyclisierun. It wasn't just in Ameiser acid, chloroacetic acid and m-cresol soluble, but also in solvents of the amide type, such as. I. N-methylpyrrolidone, Ν, Ν-dimethylacetamide and D methylformamide.

B eis ρ ie I e 47 to 62
(Polybenzimidazoles)

The cyclization of every polyamideimine. as shown in Table 5, under the same conditions as in the example! 46 realized by means of formic acid. In each case, a cyclized polymer was obtained in the form of a homogeneous solution at the end of the reaction and could be used directly as a solution for molding such articles as a film. The obtained polybenzimidazoles were in formic acid, dichloroacetic acid, m-cresol and N-methylpyrrolydone soluble. The infrared absorption spectrum showed that all the polymers obtained had been almost completely cyclized. The inherent viscosity of each of the cyclized polymers in formic acid is shown in Table 5. It was observed that the polybenzimidazoles obtained had no clear softening point at a temperature below 300.degree. C. on a hot plate, with the exception of the polyamidebenzimidazole obtained in Example 60, which ^{softened at a temperature in the vicinity of 300.degree.} C. and that obtained in Example 57 polymer, d; .s melted at a temperature near 300 ⁰ C.

B is ρ ie 1 e 63 to 76
(Polybenzimidazoles)

Each of the polyamideimines shown in Table 6 was in a mixture of N-methylpyrrolidor and formic acid cyclized. In each example, the mixed solvent consisted of 10 parts of N-methylpyrrolidone and a part of formic acid, and the polymer was homogeneously therein in a concentrate

ίο tration of 10 to 15% solved. The solution was then heated to 130 to 150 ⁰ C Einei subjected to reaction for 3 hours. The polymer was obtained as a homogeneous solution at the end of the reaction and could be used directly as a solution for shaping an object, such as, for. B. a movie, use! will. The inherent viscosities of the polybenzimidazoles obtained in N-methylpyrrolidone are shown in Table 6 at the same time. The infrared absorption spectrum indicated the disappearance or weakening of a characteristic absorption of the amide group and the occurrence of a characteristic absorption of the benzimidazole group in the vicinity of 1380 cm- ', and it can be confirmed that all of the polymers were almost completely cyclized. The polybenzimidazoles obtained according to these examples showed no clear softening point at a temperature below

Table 5 Polyamideimine
Example no. >, i " _h the poly
benzimidazole 300'C a hot plate. Ί inh Polybenz example
No. in formic acid 30 Table 6 0.89 imidazole
V Inh 0.80 0.85 7th
O 0.51
0.45
0.30 example Polyamide imines 0.84 0.81 47
4c O
10 0.45 No. Example no. 0.73 0.73 HO
49 1 1 0.85 35 63 13th 0.29 0.82 50 12th 0.55 64 15th 0.65 0.31 51 14th 0.61 65 17th 0.71 0.53 52 16 0.51 66 19th 0.46 0.78 53 20th 0.51 67 23 0.59 0.40 54 21 0.36 40 68 25th 0.80 0.42 55 22nd 0.25 69 26th 0.45 0.71 56 24 0.56 70 27 0.65 0.40 57 28 0.48 71 31 0.43 0.52 58 29 0.43 72 32 0.40 0.45 59 30th 0.54 45 73 34 0.33 60 33 0.65 74 35 61 36 75 37 62 76 38

Claims (1)

Patent claims: 1. A process for the preparation of polybenzimidazoles, characterized in that one polyamidimines, which by reacting aromatic triamines or tetramines of the general formula