CA1044397A

CA1044397A - Aromatic polyketones

Info

Publication number: CA1044397A
Application number: CA204,546A
Authority: CA
Inventors: Viktors Jansons; Klaus J. Dahl
Original assignee: Raychem Corp
Current assignee: Raychem Corp
Priority date: 1973-07-12
Filing date: 1974-07-11
Publication date: 1978-12-12
Also published as: NL7409407A; IT1030589B; SE407419B; BE817628A; FR2236884B1; ATA578074A; JPS5039399A; NL186451B; DE2433278A1; NL186451C; DE2433278C2; JPS59113030A; IL45249A0; FR2236884A1; IL45249A; JPS6254341B2; AT363255B; JPS604210B2; AU7119774A; SE7409131L

Abstract

ABSTRACT OF THE DISCLOSURE

Helt-stable aromatic polyketones useful in, eg, electrical insulation and comprised of, eg, the recurring unit

Description

~044~97 of recent years, aromatic polyketones have generated widespread academic interest by reason of their resistance to thermal degradation the interest being concentrated on poly~etones containing the repeating unit ~0 ~CO ' -' Throughout the specification and claims, the ring -system i8 to be read as aromatic. Polyketones having the ahove repeat unit may be prepared as suggested ~ `
in Bonner U.S. Patent No. 3,065,205, by Friedel-Crafts catalyzed polymerization of phosgene and diphenyl ether. The same repeat unit is additionally described, e.g., in British Patent No. 971,227 to result from polycondensation of diphenyl ether-4-carbonyl chloride, and from the reaction of diphenyl ether and diphenyl ether-4,4'-dicarbonyl chloride. ' A number of patents which include reference to improved methods of making such polyketones have since issued. For example processes disclosed in U.S. Patents 3,441,538 and 3,442,857 employ hydrogen fluoride boron trifluoride catalysts. Melt processable polymers having the above-mentioned repeating unit are described in U.S. Patent No. 3,953,400 is ued to Kiau~ J. Dahl, on 27th April, 1976, where additional . .

- 2 -' .

art is discussed.
Aromatic polyketones having other repeat units have also been investigated. Melt processable polyketones having the repeat unit S ~O~Co--are described in U.S. Patent ~o. 3,914,298 issued ;
21st October, 1975, to Xlaus J. Dahl as resulting t from e.g., HF/BF3-catalyzed, polymerization of biphenylyl-oxybenzoyl chloride. British Patent No. 1,078,234 describes polymers having the repeat unit , ~: ~ ~ ~ ' and melting at 350 from reaction of hydroquinone and 4,4'-difluorobenzophenone.
It would be of substantial advantage-if aromatic polyketones having desirable properties could be obtained from materials more readily available than certain starting materials previously employed.
The aromatic polyketone having a repeating unit ~ O--~ CO ~ (~0 .
has been prepared by the reaction of diphenyl ether i "

1~439~
and terephthaloyl chloride, but U.S. Patent No. 3,516,966 reports that the HF/BF3-catalyzed polymerization of those reactants affords melt-unstable product, and this patent describes the preparation of a copoly-ketone having a substantial content of isophthaloyl units, and reports the product as melt stable. While this process apparatus affords polymer of satisfactory molecular weight, compression molded slabs exhibit excessive gel content, indicative of a substantial - ~-degree of thermal crosslinking during melt processing.
It appears that diphenyl ether is unstable in the HF/BF3 system under the conditions described in U.S.
Patent ~o. 3,516,966 leading to undesirable side ; reactions.
The present invention provides a certain group of polyketones which enable an inherent viscosity ;
reà~sonably stable to high temperature processing, e.g., to compression moulding at 410C for 5 minutes !~ at 10~000 p.s.i. ~~ 7 x 106 kg/m2J.

- According to this invention there are provided aromatic polyketones comprising the recurring structural unit (I~
~ ~o~o~xo~CO~o~CO- ' wherein ea~h of x, m and n, which may be the same or different, is 0 or l, p is an integer from l to ..
4, n is 0 where x is l, and wherein when p is greater .
- 4 - ; ~

- , . - .~ , ~, , : . - :. : : . . . :, .. , . -.: :: - - .: : .

than 1 m is 1 and x is o, the inherent viscosity -~
of which polymers is greater than 0.4 and which is essentially unaffected by compression moulding at 410C for 5 minutes at 7.0 x 106 kg/m2. The symbol ~ represents a phenylene ring that has para linkages, which are preferred, meta linkages, or mixtures of para and meta linkages, of which mixtures those containing more than 5~% of para linkages are preferred. Polyketones that are composed of, especially those consisting essentially~f, one single repeating -unit of the formula above, as opposed to a mixture of two or more such units, are preferred, especially when an all-para unit which yield linear crystalline polymers when prepared by the processes described below.
Representative coreactants useful in forming -the homopolymers which are preferred in the practice of this invention are listed in the table which follows.
Each is a known compound which is obtainable by standard procedures, e.g., those described in the literature.

10443~7 .,, .~.1 ,~

,~ O ~ O O o ~ o ~:

~ ~ ~ ~' 'u ~ 'U

-.
:- -~ ~-"' U N
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~1 ~UId -~ ~ Z; ~ ,i ,~

~' ~ X I o o -1 o o ' ', ~: ~ ! -' -' : .:
0 0 - ' ' ' ~ l , ,, ,, " ,, -:
, l :: 2~ -~0~439~ :
In the case of the electrophilic reactant, the displaced group is preferably chlorine but may be~ for example, methoxy or hydroxy. For the case where p is 2, 3 or 4, any of the electrophilic coreactants may be employed with, respectively, tetra-, penta- or hexaphenylene ether. The first-named reactant is obtainable by e.g.~ condensation of 2 moles of phenol with 1 mole of 4l4'-dibromodi-phenylether. Pentaphenylene ether is obtainable, -for example, by condensing 1 mole of 1,4-dibromo-benzene and 2 moles of 4-hydroxydiphenylether, -while the last-mentioned coreactant is obtainable, for examp?e by condensation of 1 mole of 4,4'-dibromo-diphenylether and 2 moles of 4-hydroxydiphenylether.
Preferably, essentially all of the repeating units of the polymer are identical. In such cases, the essentially para polymer is expected to exhibit thermooxidative stability superior to polymers - characterized by substantial meta linkage, as is the case where, e.g., mixtures of terephthaloyl and isophthaloyl chloride are employed as electrophilic reactants. Of course, even where only terephthaloyl cbloride or a like "para" reactant is employed, it is believed that a minor number to the extent of a few percent, of the repeating units will contain~ ;
linkages arising from attack of the electrophilic ':

. . .. . . - . , . : . -.. . . . -reactant on the growing polymer chain at positions other than para.
More generally, the invention also provides copolyketones, consisting essentially of a single repeating unit conforming to the structural formula last depicted. Among suitable candidates for copoly-: merization may be mentioned the following nucleophilic coreactants: ` .
diphenyl sulfide 4,4~-diphenoxybiphenyl p-phenoxyphenol 2,2'-diphenoxybiphenyl p-phenylphenol 1,2-diphenoxybenzene dibenzofuran 1,3-diphenoxybenzene thianthrene l-phenoxynaphthalene phenoxathiin 1,2-diphenoxynaphthalene 1~ phenodioxin diphenyl ether .~
diphenylene l,5-diphenoxynaphthalene ..
Similarly, the following electrophilic coreactants .
for copolyketone formation may be mentioned: . . ~: .
phosgene . :~
carbonyl difluoride :.
isophthaloyl chloride benzene-1,4-di~sulfonyl chloride) ::~
benzene-1,3-di(sulfonyl chloride~ -:
2-chlorobenzene-1,4-disulfonyl chloride thio-bis(4,4'-benzoyl chloride) oxy-bis(4,.4'-benzene ~ulfonyl chloride) , ~, '' .': ;' '' 10~43g7 : ' benzophenone-4,4~-di(carbonyl chloride~
oxy-bis(3,3'-benzoyl chloride) thio-bis(3,3'-benzene sulfonyl chloride) .:
; oxy-bis(3,3t-benzene sulfonyl chloride~
diphenyl-3,31-ditcarbonyl chloride~ .
carbonyl-bis(3,3'-benzoyl chloride~
: sulfonyl-bis(4,4'-benzoyl chloride~
sulfonyl-bis(3,3'-benzoyl chloride~
sulfonyl-bis(3,4'-benzoyl chloride3 thio-bis(3,4'-benzoyl chloride~
diphenyl-3,4'-di(carbonyl chloride) oxy-bis[4,4'-(2-chlorobenzoyl chloride~]
naphthalene-1,6-ditcarbonyl chloride) naphthalene-l,~-di(carbonyl chloride~
naphthalene-2,6-di(carbonyl chloride~
naphthalene-1,5-di(sulfonyl chloride) oxy-bi~[7,7'-naphthalene-2,2'-di(carbonyl -~ chIoride)]
thio-bi~[8,8'-naphthalene-1,1~-di~carbonyl .
chloride)] ~;
-~ 7,7'-binaphthyl-2,2'-di(carbonyl chloride~ ~
diphenyl-4,4'-di(carbonyl chloride~ --carbonyl-bis[7,7'-naphthalene-2,2'-di(carbonyl : ch}oride)]
: 25 sulfonyl-bis[6,6'-naphthalene-2,2'-di(carbonyl ~:~
chloride)3 - _ 9 _ ':

. .. . . . . j., .. , , j " , j;,., ,. . . . : . . . . ., . . . ~ i . .:. - . , ~ .,. . - . . . . . . i . - ` . . .

: - - . - . :. .. ~

~4397 - -:
dikenzofuran-2,7-di~carbonyl chloride) The preferred process conditions are preferably ~ ;
employed in the formation of homopolymers, many of them novel, from the above-listed coreactants. Where the copolyketone coreactant is more than binucle?r the copolyketone should, by preference contain at least 70h, most preferably at least about 8~o~ repeat units of the general formula last depicted.
In a further embodiment of the invention we prepare linear, crystalline melt-stable polymers predominantly and, most preferably, essentially comprising the repeat unit -... ..

~*C~x~~ ' ' wherein the moieties of structure ~ are~ for each repeat unit, independently selected from the group consisting of ~ and ~ , x and m being as earlier defined. Preferably, up to 50%
of the ~ moieties are ~ , most preferably from about 10% to about 50X. &ch polymers are prepared ju8t a9 in the case of all-para polymers, save that some or all of the electrophilic terephthaloyl chloride ~ -, reactant is replaced by isophthaloyl chloride. The use of mixtures of terephthaloyl and isophthaloyl chlorides in varlous proportion~ results in variation .,:

- 10- ~, , ~0443~7 of the melting temperature between 271 and 360C for the system ~o~o ~ CO~CO--: Copolymers of this type confer greater latitude in extrusion temperatures and afford improved compatibility for blending with other resins to obtain special effects, for example plasticization. Additional advantages which may acc~ue from this deviation from an all-para polymer system include changes in crystallization behaviour and attendant effects on stress corrosion in fluids, or at elevated temperatures.

.

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1~4397 Preferably the polymers of the invention have inherent viscosity of at least about 0.4, more preferably from about 0.5 to about 2.0, and most preferably from about 0.7 to 1.5. Molecular weight may be controlled by capping, as disclosed in the above-mentioned U.S. Patent No. 3,953,400. Pre~erred capping agents contain a ketonic linkage, e.g., 4-phenoxybenzophenone. ~he present invention accordingly provides a capped polymer of the above-specified formulae.
In preparing the polymers of the invention by the preferred procedure, equimolar amounts of ~ --nucleophilic and electrophilic tpreferably dichloride~ coreactants are combined, optionally with minor amounts of monofunctional capping agent, and sufficient anhydrous HF added to form, at 0C, a 10%
wt. solution. At -20C to 10C, preferably 0 C, ;~
after first allowing all HCl or equivalent to evolve, BF3 is added under 30 p.s.i. (2.1 kg/cm2~ pressure~
the material permitted to react for about 6 hours, and the polymerization mixture is then diluted with S2 or additional HF to form a solution containing about 5% wt solids. Recovery is by spray drying or precipitation in a *Waring blendor into H20 (room temperature~ or methanol t-78C). The fluorine and boron content of the resulting product is reduced by 1 2 : :

.. . .. ,: .
"Waring is a trade mark. ~

.~

1~44397 water wash and the material then dried at 150C and 20 mm Hg for 3 to 5 hours. All reactions are preferably performed in a transition metal-free environment. By the process preferably used for - 5 preparing the polymers of the invention, a substantially linear, crystalline polymer may be obtained, which has desirahle properties, for example, when used as an electrical wire, cable, or other component insulation.
~ In the following Exiamples of preferred embodiments of the invention, all parts and percentages are by weight and all temperatures in C
unles~ otherwise indicated.

A~ : :
i' :' ' :'.' ' ' ~ ' ... 1 ' ~" . ' .

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A 50 ml. polychlorotrifluoroethylene tube`
was charged with 1.2984g (4.95 m~oles) of 1,4-diphenoxy-benzenej 1.0049g (4.95 mmoles) of terephthaloyl chloride, 0.0027 g (0.01 mmoles~ of 4-phenoxybenzophenone tcapping agent) and a stir bar. ~o this mixture was slowly added 20 ml of anhydrous hydrogen fluoride. The tube was then connected to a polychlorotrifluoroethylene vacùum line tToho Kasei Co. Ltd., Osaka, Japan) and purged with ni~rogen while cooling to 0C. Boron trifluoride gas was admitted and the reaction mixture -was held at 2.1 kg/cm2 pressure for 6 hr. to give a viscous orange-red solution. Excess boron trifluoride was purged from the reaction system, the polymer solution ;
was diluted with anhydrous hydrogen fluoride, and then poured into rapidly stirred, cold (-78) methanol.
The resultant polymer precipitate was filtered and washed with water and methanol, followed by drying i at 180-200/20 mm Hg to yield colourless, fluffy material, which was annealed at 230 for 20 minutes. Inherent vis~osity before and after compression molding, ele-mental composition and physical characteristic~ of the polymer are set out, in Tables II - IV, infra. In - -i the case of this and the following Examples, compression molding at 410 for 5 minutes at a pressure of 7.03 x 106 kg/m2 afforded nearly colourless, flexible slabs.

.~ - .

~, .

It is particularly noteworthy that in every case inherent ~iscosity was essentially unaffected by compression molding. mis also held true when, in related work, diphenyl ether and terephthaloyl chloride were reacted by the foregoing procedure to afford a polymer having the repeat unit ~ O ~CO ~ CO

in the latter case inherent viscosity of the powder was 0.53 and that of the slab 0.49. All inherent viscosities are mean values obtained according to the method of Sorenson et al, Pre~arative Methods of PolYmer ChemistrY, Interscience ~1968~ p. 44 ~0.1 g.
polymer in 100 ml. soln. of concentrated H2S04 at 25C3. Melting points were determined with a Perkin-J 15 Elmer Diferential Scanning Calorimeter.

The additional polymers listed in Table 1 were prepared following the procedure of Example 1 --and their properties determined as set out in Tables II - IV. In the case of Example 5 no melt point was determined, though the material is estimated to melt - at a temperature within the range 300-350C. -,~. .

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, S~ ~1 o l o ''~ $ .~~
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Polymerization of 1,4-diphenoxybenzene with isophthaloyl chloride Anhydrous hydrogen fluoride was saturated with boron trifluoride at -23C, and 2.1 kg/cm (30 psi) p~essure for 4 hr. A 50-ml reaction tube was charged with 1.3050 g (4.975 mmoles) of 1,4-diphenoxybenzene, 1.0151 g (5 mmoles) of isophthaloyl chloride, 0.0137 g (1 mole %) of ~-phenoxybenzo-phenone and a stir bar. To this mixture was added slowly 10 ml of the cold (-78) boron trifluoride saturated hydrogen fluoride solution, and the reaction tube was connected to the vacuum line. A boron trifluoride pressure of 30 psi (2.1 kg/ m2) was applied and the polymerization was allowed to proceed at 0 for 16 hr. to give a viscous, orange solution. Excess boron trifluoride was purged from the reaction system, the polymer solution was diluted with hydrogen fluoride and then poured into rapidly stirred, cold (0) water. The resultant polymer precipitate was filtered and washed with water, followed by drying at 150/20 mm Hg to yield colorless, fluffy material. The material showed an inherent viscosity of 1.36. Compression molding at 400 for 5 min produced a flexible slab of inherent viscosity 1.37. Differential scanning ; ~ -colorimetry indicated a glass transition temperature of 153 and a crystalline melting temperature of 271 (scan rate: 20jmin). The~mogravimetric analysis in air showed a 10% weight loss at 600 (scan rate: 20D/min). Molecular spectroscopy revealed the following data which are consistent with a linear polymer of repeating unit: .

_~o ~ ~3 ~

infrared (film cast from hydrogen fluoride): 1655 cm l ~ketone link3, 1235 cm~
[ether link]; ultraviolet (conc. sulfuric acid) -~ max., 407 nm (e, 4.8 x 104);
nuclear magnetic resonance (ClCF2-COCF2Cl D20/CDC13 = 1:1): ~, ppm: 7.18 ~doublet, 4H, J = 9 Hz), 7.28 tsinglet, 4H), [protons in ortho position to -ether linkage]; 7.82 (singlet, 3H), 8.08 (doublet, 4H, J = 9 Hz), 8.18 ~sing-., ,~.1, g.

--1~44397 : ~:
let, lH) ~protons in proximity of ketone linkages3. ~:~
EXAMPLE 7 .:
Polymerization of 1,4-Diphenoxybenzene with Mixture of Terephthaloyl Chloride .-and Isophthaloyl Chloride The experiment detailed in the precedin~ example was repeated, but mixtures of terephthaloyl chloride and isophthaloyl chloride were used. ~ ~ .
Acid chloride ratios employed and data of polymer characterization are shown .. ^ - .:- .
in Table V.

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rl _1 9 ~I t~ 1 ~ .~ td O L~ O ' ~ E--~ H __ J
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1~44397 The products of this invention are film and fiber-forming polymers suitable for use in electrical insulation, as by melt extrusion over wires, cables, and the like. Preferred polymers are crystalline materials melting at a temperature in the range 340-404 C. ~hose in which carbonyl moieties are present in a numerical proportion greater than ether oxygen may be expected to crystallize substantially more quickly than, e.g., polythenzophenone ether)~, offering the possibility that the post-annealing step commonly practised with extrudates of the latter polymer can be eliminated without adversely af~ecting properties such as tensile strength and resistance to scrape abrasion and en~ironmental stress corrosion.
Polymers prepared according to this invention whose melting points are 400C or higher when employed ;
in electrical insulation have the advantage of res-i~ting loss of insulative integrity if inadvertèntly contacted with a hot soldering iron.
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Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A polymer of which at least some of the recurring units are of the formula (I) wherein the symbol represents a phenylene ring having para linkages, a phenylene ring having meta linkages, or a mixture of such rings, wherein each of x, m and n, which may be the same or different, is 0 or 1, p is 1, 2, 3 or 4, n is 0 when x is 1, and m is 1 and x is 0 when p is greater than 1, the inherent viscosity of the polymer being at least about 0.4 and being essentially unaffected by compression moulding at 410°C for 5 minutes at 7.0 x 106 kg/cm2.

2. A polymer as claimed in claim 1, consisting essentially of identical recurring units within the formula I.

3. A polymer as claimed in claim 2, wherein the symbol represents a para-linked phenylene group.

4. A polymer as claimed in claim 3, which is a substantially linear crystalline polymer.

5. A polymer of which at least some of the recurring units are of the formula (II) wherein each of x, m and n, which may be the same or different, is 0 or 1, p is 1, 2, 3 or 4, n is 0 when x is 1, and m is 1 and x is 0 when p is greater than 1, the inherent viscosity of the polymer being at least about 0.4 and being essentially unaffected by compression moulding at 410°C for 5 minutes at 7.0 x 106 kg/cm2.

6. A polymer as claimed in claim 5, which is substantially linear.

7. A polymer as claimed in claim 5 or claim 6, wherein a major proportion of the recurring units are of formula (II).

8. A polymer as claimed in claim 5 or claim 6, which consists essentially of units of formula (II).

9. A polymer as claimed in claim 5 or claim 6, wherein substantially all of the recurring units of the formula (II) are identical.

10. A polymer as claimed in claim 5 or claim 6, wherein, in each of the recurring units of the formula (II), m is 1 and each of x and n is 0.

11. A polymer as claimed in claim 5 or claim 6, wherein, in each of the said repeating units of the formula (II), each of m, n and x is 0.

12. A polymer as claimed in claim 5, which has an inherent viscosity of at least 0.5.

13. A polymer as claimed in claim 12, which has an inherent viscosity between 0.5 and 2Ø

14. A polymer consisting essentially of the recurring unit (III) wherein each of m, n and x is 0 or 1 and when x is 1 n is 0, and having an inherent viscosity that is essentially unaffected by compression moulding at 410°C for 5 minutes at 7.0 x 106 kg/cm2.

15. A polymer as claimed in claim 14, which has an inherent viscosity of at least 0.5.

16. A polymer as claimed in claim 14, which has an inherent viscosity between 0.5 and 2.0

17. A polymer as claimed in claim 1, consisting essentially of the recurring unit (IV)

18. A polymer as claimed in claim 1, consisting essentially of the recurring unit (V)

19. A polymer as claimed in claim 1, consisting essentially of the recurring unit (VI)

20. A polymer as claimed in claim 1 consisting essentially of the recurring unit (VII)

21. A polymer as claimed in claim 1 consisting essentially of the recurring unit (VII)

22. A shaped structure comprising a polymer as claimed in any one of claims 1, 5 or 14.

23. A film, fibre or electrical insulating material comprising a polymer as claimed in any one of claims 1, 5 or 14.

24. A linear, crystalline melt-stable polymer containing repeat units of the formula wherein x, m and have the meanings specified in claim 1.

25. A polymer as claimed in claim 24, which consists essentially of the repeat units specified therein.

26. A polymer as claimed in any one of claims 1, 5 or 14, which is capped.

27. A polymer as claimed in any one of claims 1, 5 or 14 which is capped by 4-phenoxybenzophenone.