FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
PROVISIONAL SPECIFICATION
(See Section 10; rule 13)
TITLE OF THE INVENTION
Cross-linkable poly(aryl ether ketone)s and articles made therefrom
APPLICANTS
SOLVAY SPECIALITIES INDIA PRIVATE LIMITED of
401, Suraj Prakash, 1st floor, 86, Shankar Ghanekar Marg,
Prabhadevi, Mumbai 400 025. (India)
PREAMBLE TO THE DESCRIPTION
The following provisional specification particularly describes the invention and the manner in
which it is to be performed.

Cross-linkable poly(aryl ether ketone)s and articles made therefrom
BACKGROUND OF THE INVENTION
Polymers, particularly plastics are usually linear long chain molecules of high molecular weights. The linearity gives some advantages, notably greater crystallization and therefore mechanical strength, and better thermal stability. However, presence of branches on linear polymeric chains has its advantages too. Notably, better melt strength of the material for film forming, coating, blow molding, on one hand and lower solution viscosity making higher solid content of solution feasible on the other hand as compared to linear polymers of similar molecular weights. Long chain branching, due to the presence of entanglements,
also tends to make these materials toughened as compared to linear polymers of similar structures.
Similarly, specialty plastics (Tg >160 C), due to their high temperature processing (>300 C) requirements have structural features with groups which are essentially non-reactive. Thus, groups such as -OH, -COOH, -CN, and others
are acidulously avoided. The presence of such reactive groups on the polymer chains lead to rapid uncontrolled cross-linking or degradation. Some side effects like crumbling of melts into powders are also very common. It is well known ' therefore that specialty polymers are linear and rigorously end capped materials, so that they can maintain their structures during the processing in extrusion,
injection molding, etc. They show very high thermal stability at temperatures like 380C without change in melt viscosities for 60-120 minutes in rheometers under high shear conditions. Normal engineering plastics, like polyamides, polyesters, polycarbonates are immediately affected and get cross-linked leading to much higher melt viscosities in less than a few minutes, making them
unprocessible at such high temperatures.
In general, branching particularly in specialty plastics (Tg > 180°C), is also avoided. The main reason for this is reduced thermal stability of branched polymers, due to reactive branch points creating cross-linking, degradation or color problems at high temperature processing.
If one can overcome these issues, branched polymers with reactive end
groups can be used to much advantage that they offer over similar but linear, end capped polymers.






The Applicant has found that shaped articles, or parts of shaped articles can easily be made from poly(aryl ether ketone)s comprising chains which comprise more than two reactive end groups. These polymers feature some distinct advantages, in particular in lower solution viscosities but higher melt viscosities as compared to linear poly(aryl ether ketone)s of similar molecular weight. DESCRIPTION OF THE INVENTION
A first aspect of the present invention is related to cross-linkable poly(aryl ether ketone)s comprising chains which comprise more than two reactive end groups selected fromhalogen and hydroxyl groups and to a method for their preparation.
Another aspect of the present invention is related to an essentially at most two dimensional shaped article, or part of shaped article, comprising a material comprising a cross-linked, generally thermoset, poly(aryl ether ketone).
Still another aspect of the present invention is related to a method for the preparation of said at most two dimensional articles, or part of shaped articles, comprising a material comprising a cross-linked poly(aryl ether ketone).
For the purpose of the present invention, the term "poly(aryl ether ketone)" is intended to denote any polymer of which more than 50 wt. % of the recurring units are recurring units (Rl) comprising at least one carbonyl group in-between two arylene groups, said recurring units (Rl) being of one or more of the following formulae :

Os
X-Ar)„-

(I)

(in


/!II_L£\ fBamUti!\ JWBSEBX\/0\i-C0H\J~0
(III)



X—(Ar~-X<
O—
-o



(IV)







X—(Ar-X
(V)



wherein :
- Ar is independently a divalent aromatic radical selected from phenylene, biphenylene or naphthylene,
- X is independently O, C(=O) or a direct bond,
- n is an integer of from 0 to 3,
- b, c, d and e are 0 or 1,
- a is an integer of 1 to 4, and
- preferably, d is 0 when b is 1.
Recurring units (Rl) may notably be chosen from :



-o
(VI)




o
o-
(VII)




CO
(VIII)




(IX)




(X)


CO—
(XI)







o—&. />—o
CO—
(XII)




~0"co"O~o-0""°
CO—

(XIII)


co-

(XIV)


CO—

(XV)






co-
o—4. />— co

(XVI)






o~~
CO
0—4 />—CO

(XVII)





o—
(XVIII)





co-4 ^-co-
(XIX)




CO—d /)—CO-
(XX)

and






o
co-
CO
CO
ra
(XXI)

Preferably, recurring units (Rl) are chosen from :



(VI)

o—
(VII)

and




o

(IX)

More preferably, recurring units (Rl) are :


(VII)

For the purpose of the present invention, a poly(ether ether ketone) (PEEK)
is intended to denote any polymer of which more than 50 wt. % of the recurring units are recurring units (Rl) of formula (VII).
For the purpose of the present invention, a poly(ether ketone) (PEK) is intended to denote any polymer of which more than 50 wt. % of the recurring units are recurring units (Rl) of formula (VI).
For the purpose of the present invention, a poly(ether ketone ketone) (PEKK) is intended to denote any polymer of which more than 50 wt. % of the recurring units are recurring units (Rl) of formula (IX).
Preferably more than 70 wt. %, and more preferably more than 85 wt. % of 20 the recurring units of the poly(aryl ether ketone) are recurring units (Rl). Still more preferably, more than 90 wt. % of the recurring units of the poly(aryl ether ketone) are recurring units (Rl).

Excellent results were obtained when the poly(aryl ether ketone) is a poly(ether ether ketone) homopolymer, i.e. a polymer of which essentially all, if not all, the recurring units are of formula (VII). V1CTREX® 150 P and VICTREX® 450 P PEEKs from Victrex Manufacturing Ltd., and 5 KETASPIRE™ and GATONE® PEEKs from Solvay Advanced
Polymers, L.L.C. are examples of poly(ether ether ketone) homopolymers.
The poly(aryl ether ketone) can be amorphous (i.e. it has no melting point) or semi-crystalline (i.e. it has a melting point). It is usually semi-crystalline ; the case being, the melting point of the poly(aryl ether ketone) is advantageously
greater than 150 °C, preferably greater than 250°C, more preferably greater than 300°C and still more preferably greater than 325°C.
For the purpose of the present invention, the term "cross-linked poly(aryl ether ketone)"is intended to denote a poly(aryl ether ketone) in which chemical links have been established between the molecular chains of the polymer. The
cross-linked poly(aryl ether ketone) is preferably a thermosetting resin. When extensive, as in most thermosetting resins, cross-linking makes one infusible super-molecule of all the chains forming a three-dimensional or network polymer, generally by covalent bonding. Thermosetting materials cross-link generally under the influence of heat and/or catalysis, irradiation with high-
energy electron beams, or chemical cross-linking agents, such as organic peroxides.
For the purpose of the present invention, the term "cross-linkable poly(aryl ether ketone)"is intended to denote a poly(aryl ether ketone) which can be cross-linked.
The cross-linkable poly(aryl ether ketone) comprising chains which
comprise more than two reactive end groups selected from halogen and hydroxyl groups according to the present invention can be prepared by two methods, namely the nucleophilic and the electrophilic polymerizations.
The first method comprises the nucleophilic polymerization of i) a
polyfunctional aromatic compound having at least three functional groups, wherein at least one of the functional groups comprises a halogen, with ii) a dinucleophile and optionally iii) a difunctional aromatic compound, wherein at least one of the two functional groups comprises a halogen, such as the method described in U.S. Pat. Appl. 10/779207, the whole content of which is also
herein incorporated by reference.


This method allows the preparation of polymers capable of undergoing curing reactions (cross-linking). The thermosets are prepared in a single step utilizing mostly commercially available starting materials. It requires the polymerization of a polyfunctional aromatic having at least three functional
groups or, preferably, the copolymerization thereof with a difunctional aromatic compoundusing a dinucleophile , preferably a diol as a linking agent. By selecting the proportions of each of the components, a stable polymer or copolymer is provided having the desired degree of workability prior to curing and which is subsequently curable into a hygrothermally stable material having a
high glass transition temperature.
This method requires the use of a polyfunctional aromatic having at least three functional groups wherein the functional groups may comprise a combination of one halogen and two hydroxyl groups, or more preferably, two halogens and one hydroxyl group or most preferably, three halogens. The
halogen may comprise Br or I, more preferably F or most preferably CI. The aromatic is selected so as to have electron withdrawing properties and can thus include, but is not limited to, a sulfone, carbonyl or phosphine oxide. For good reactivity, the functional groups are preferably in the ortho or para positions in the rings relative to the electron withdrawing groups. The most preferred such
aromatic is a trifunctional aromatic comprising 2,4,4-trichlorodiphenylsulfone. The polyfunctional aromatic having at least three functional groups as set forth above is optionally and preferably copolymerized with a difunctional aromatic wherein the functional groups preferably comprise halogens, either Br or I, or more preferably F or most preferably CI. The aromatic has electron
withdrawing properties and can include, but is not limited to a dihalobenzenoid compound. The most preferred difunctional aromatic for copolymerization with 2,4,4'-trichlorodiphenylsulfone comprises 4-chlorophenyl sulfone.
In its most general form said nucleophilic polymerization allows the preparation of polymers according to the following scheme :
Equation I :

where n is 3 or more, the three or more functional groups X and the two functional groups Y can be the same or different, wherein at least one of the X's and one of the Y's comprises a halogen and the remaining X's and Y's are

independently selected from the list of nucleophiles (shown in their protonated form):
o
N'
\f R -NH
-OH
and halogen, the groups —Nu are selected independently from the list of nucleophiles (shown in their protonated form) :


-OH

-SH

R
-NH

the base is any base strong enough to deprotonate the nucleophile or to accept the acid liberated on reaction. It will be recognized by one skilled in the art that some of the nucleophiles shown do not need to be deprotonated to react with an
activated aryl halide (e.g. —NH2) while others do (e.g. —OH, -SH, -NRH where R is alkyl, aryl, alkyl ketone or aryl ketone and phthalimide). The term nucleophile is used herein to refer to both the protonated and deprotonated forms. Q is any divalent moiety and may be aliphatic or aromatic and may contain heteroatoms and additional substituents, for example to aid in solubility
or processibility.
Non-limiting examples of dinucleophiles Q(Nu)2 used in the practice of the present invention include :

OO

„.0 K


T ■>-•■

JD-O

X^r

.o'"o-°x:x


In a preferred embodiment n is 3, all X's and Y's are CI, both Nu's are -OH, the base is potassium carbonate, Ar is diphenylsuifonetriyl, Ar' is diphenyl sulfonediyl, and Q is biphenylene :
c
(i .0 ,
'V-^' .

Typically, the dinucleophile and base are allowed to react first, with
removal of water as necessary (for example, azeotropic distillation), After this step, the dinucleophile may be monoaniona or a dianion (e.g. a double alkali metal salt), depending on the relative strength of the base and first and second pKa's of the dinucleophile. In either case it is preferred to have at least one
equivalent of base for each halogen group present so that as the reaction proceeds there is enough base to form the anion of each nucleophile group.
It is preferred that the independently selected functional groups X and Y (Equation I) consist of halogen or hydroxy groups, where the moles of hydroxy groups may be the same or in excess of the moles of the halogen groups. The
excess is preferably about 1 mol %, more preferably 2 mol %, yet more preferably 3 mol %, even more preferably 5 mol %, and most preferably 6-12 mol %. A large excess may be applied as needed to control molecular weight. Optionally, X comprises all halogen groups and Y, all hydroxy groups.
As a further option, a monohalo monomer may be included to control
molecular weight.
Ar, Ar' and Ar" are aromatic rings bearing one or more substituents having electron withdrawing properties. Such substituents can include ketone, sulfone, phosphine oxide, sulfoxide, cyano, fluoro, trifluoromethyl, nitro, azo groups and the like. Ar, Ar' and Ar" may be multiring or fused ring groups including
heterocyclic rings. Halo is F, CI, Br, I, R is alkyl, aryl, alkylester, arylester, amide, fluoroalkyl, fluoroaryl, alkylketone or arylketone.


ln its most general form Q can be represented as :
a- rx^-
-i i
R.m, Ri
(mi

where m is 0 to 4 and the R(m) are independently selected from alkoxy, aryloxy, alkyl, aryl, alkylester, arylester, amide, fluoroalkyl, fluoroaryl, polyalkalene oxy. Any two adjacent R(m) may be bridging to form cyclic or heterocyclic units. Z is independently selected from the group consisting of nil, -0-, -S-, -NR- and -CR1R2-, and R1 and R2 are independently selected from alkoxy, aryloxy, alkyl, aryl, alkylester, arylester, amide, fluoroalkyl, fluoroaryl, alkylketone, or arylketone.
Non-limiting examples of difunctional groups useful in the practice of the present invention are :

o. .0 V
Cl-h T-OH
°«W*°
cr ^-^ "-^ ci
=\ P o
Non-limiting examples of trifunctional groups useful in the practice of the present invention are :



H O . C !'

°VV*°

,xxxxr

0
^0 .
t&^r

IX,


ci —
L^vri ci"
0 . ,0

Nonlimiting examples of tetra-halo monomers include :

F"

* Q OF
.J L .

O
O

CI'
F O F
11
F ^ F

CI'

CI O C!
X 4 t
ii i
A J ° !i

CI

Non- limiting examples of hexa-halo monomers include :


ci V ci

The linking agent (comonomer) preferred for the polymerization of the multifunctional aromatic having at least three functional groups or the copolymerization thereof with the difunctional aromatic is derived from dihydric polynuclear phenols, preferably dihydroxy aromatic compounds. A most
preferred linking agent for the polymerization of 2 ,4,4'-trichlorodiphenylsulfone or the copolymerization of 2,4,4'- trichlorodiphenylsulfone with 4-chlorophenyl sulfone is derived from 4,4'-biphenol.
By combining the polyfunctional aromatic having at least three functional
groups, or its combination with the difunctional aromatic, with an excess of the diol linking agent, the polymerization reaction is controlled so as to limit the molecular weight of the resulting polymer or copolymer and thus preserve the workability of the material prior to curing. An excess is defined in terms of the total number of hydroxyl groups of the linking agent relative to the total number
of functional groups in the poly- and difunctional aromatics, wherein the former preferably exceeds the latter, preferably by at least 1 % or more preferably, by at least 10%.
Reaction of the diol linking agent with K2CO3 or Na2CO3 or an appropriate base as is well known in the art turns the diol into the corresponding double
alkali metal salt which allows the polymerization reaction to proceed to
completion. The resulting material is stable, soluble in a variety of organic solvents and workable so as to readily facilitate molding, compositing, its use as an adhesive, coating or blending component. Subsequent curing at an elevated temperature greater than about 250°C, preferably 300°C or most preferably
340°C, yields a material that has a very high glass transition temperature.


The second method for the preparation of a cross-linkable poly(ether ether ketone) comprising chains which comprise more than two reactive end groups selected from halogen and hydroxyl groups, comprises an electrophilic polymerization of phenoxy phenoxy benzoic acid using an alkane sulfonic acid 5 as solvent, a condensing agent, optionally a diluent, in the temperature range of 40 to 160° C, followed by precipitation of the said poly(ether ether ketone) in water after it has achieved the desired inherent viscosity (Inh.V.) and after the removal of the acid residues with treatments with water and later with organic solvent like DMAc or DMF or with bicarbonate solution, filtering and drying it
to give the cross-linkable poly(ether ether ketone), such as the one described in U.S. Pat. 6,566,484, the whole content of which is also herein incorporated by reference.
Said second method involves reacting phenoxy phenoxy benzoic acid (PPBA) in alkane sulfonic acid with a condensing agent, with or without a
diluent at 40° to 160° C. The alkane sulfonic acid used can be any aliphatic sulfonic acid including haloalkane sulfonic acid, preferably methane sulfonic acid (MSA), trifluoro or trichloro methane sulfonic acid. The condensing agents used for example are thionyl chloride, phosphorous trichloride, phosphorous pentachloride or phosphorous pentoxide, methane sulfonic anhydride or their
mixtures. The diluent is, for example, a non-polar aprotic solvent such as
methylene chloride, ethylene dichloride, or sulfolane, or their mixtures or any of the polar organic compounds remaining inert in this system.
The alkane sulfonic acid mixture with its anhydride was found to be a solvent as well as a powerful catalyst for polymerization, of phenoxy phenoxy
benzoic acid (PPBA) to give PEEK. It was also found that in MSA-MSAN system, the methane sulfonic acid anhydride (MSAN), gets easily reconverted into MSA after reaction work-up in water, so that recycling is possible and waste generation is minimal, MSA being recoverable and recyclable. Additionally, the MSAN need not be prepared separately and added during the reaction, but can
also be prepared in-situ. When the reaction mass is added into water during the work-up of the reaction, the acid remains dissolved in water and the polymer easily precipitates out. The polymer is isolated by filtration, and is washed and dried. Any unreacted anhydride present in the reaction mass gets reconverted into the acid by reaction with water during the work-up. The resultant acid and
water mixture can be easily separated by fractional distillation and both the acid and water can be recycled for the next batch.

- 14-
In MSA-P2O5 system, similarly, MSA and H3PO4 are formed on precipitation of PEEK in water, from which MSA can be separated and reused. Thus, a significant advantage of this method is the ease of work-up and isolation of polymer due to the use of aqueous system for precipitation of PEEK. Further purification of PEEK is required to remove traces of acid, which can be
accomplished by washing with hot water containing alkali and refluxing in water again to remove last traces of salt and alkali.
Generation of MSAN is readily carried out with any of the condensing agents, thionyl chloride (SOCI2) or phosphorous pentoxide are the preferred
reagents, due again to the ease of operation and feasibility of using the byproducts, with minimum waste generation.
SOCI2 reacts with MSA to give flue gasses SO2 and HC1, which can be reacted back to give SOCI2, and recycled, (Geiko V. I., Gladushko et. al. Khim. Khim. Tecknol. 1985, 28(5) - 4 (Russ)). With P205, similar treatment yields
H3PO4, a useful acid, which also can be separated from its mixture with MSA by extraction with suitable solvents or by fractional distillation of MSA and used as such. Such recycling was not achievable when a common catalyst like AICI3 was used for polymerization.
This method makes it possible to prepare PEEK electrophilically using
homogenous solutions. The old AICI3 method was heterogeneous making
molecular weight control nearly impossible as PEEK tended to crystallise out of solution forming a slurry. In this method, rate of polymerization reaction and ultimate molecular weights can be readily controlled by a proper choice of reaction temperature, monomer concentration, and the quantity of anhydride
employed. Thus, the kinetics of polymerization is easily controlled. Another advantage is the use of an acid monomer as the precursor, instead of the acid chloride as the precursor in case of manufacture based on Friedel-Crafts synthesis with catalysts, like AICI3. As is widely known, an acid chloride is susceptible to hydrolysis, even in presence of trace quantities of water. These
problems are overcome here by using acid monomer itself.
Since preferred polymerization temperatures are low to moderate in the range of 60-100°C only, towards the end, the reaction mass viscosity increases and it makes efficient stirring difficult.
Addition of diluents, like CH2C12 or CH2C1-CH2C1 or toluene, helps
advantageously in keeping the solution stirrable and improves mixing. Another advantage derived by the addition of a diluent, which can be low boiling and


immiscible with water, is that on precipitation in hot water, it simply boils off and thus gets readily separated. Another advantage of adding a diluent is that the precipitating PEEK is obtained in this case as fine granules or powder. Without such a diluent, lumps or thick fibres are obtained requiring further size reduction. Yet another advantage of using the diluent is that the PEEK obtained as powder contains less than 10 % MSA entrapped in it, while the lumpy or fibrous PEEK contains as much as 15-25 % MSA entrapped, requiring more exhaustive post-polymerization treatments.
After separation from the reaction mass by precipitation in water, the polymer is filtered and washed conveniently free of MSA and H3PO4, if any, as shown in the examples. PEEK is subsequently treated in refluxed water, followed by refluxing in alkaline solution. Alternately, an organic base like dimethyl formamide (DMF) or dimethyl acetamide (DMAc), etc. can also be used. A formic acid treatment is optionally given to PEEK samples with higher UV absorbance (As) or high As values, to reduce them to lower As levels and to improve its color from buff to white during powder stage.
Preferably, PEEK so produced has to be made completely free of the
solvent, as even small quantities of the solvent left behind has very deleterious
effect on the processability of PEEK at high temperatures.
This electrophilic method allows the production of poly(ether ether ketone)
(PEEK), which is thermally stable and melt processible. It involves polymerising phenoxy phenoxy benzoic acid (PPBA) using alkyl sulfonic acid and a condensing agent with or without a diluent at 40-160°C. Thereafter, separating PEEK from the reaction mixture by precipitation in water and giving further water treatments for purification. Further, PEEK powder may be treates with organic solvent with or without formic acid to improve the colour.
The present invention relates also to cross-linked poly(aryl ether ketone) shaped articles, or part of shaped articles, which are essentially at most two-dimensional. These include essentially one-dimensional shaped articles like filaments or to essentially two-dimensional shaped articles like films, sheets and slabs. It relates also to performing methods of making said shaped articles, and to end-uses of said shaped articles.
Preferably, the essentially at most two dimensional article of the present invention is selected from a film, a fiber, a sheet, a slab or a hollow body. More preferably, it is a film.
Preferably, said article comprises cross-linked poly(ether ether ketone).


Preferably, said article comprises cross-linked poly(ether ketone).
Preferably, said article comprises cross-linked poly(ether ketone ketone).
More preferably, said article comprises cross-linked poly(ether ether
ketone).
From a practical point of view, any shaped article is three-dimensional, and
can thus be characterized notably by three characteristic dimensions ("length", "width" and "height"). However, some shaped articles are such that one or two of their characteristic dimensions is (are) considerably lower than respectively the other two ones or the third one. Here and wherever else used in the present
description, the terms "considerably lower" should generally be understood as "more than 5 times lower" and preferably as "more than 10 times lower", unless they characterize a "two-dimensional thickness" as defined hereafter in the description.
Precisely, for the purpose of the present invention an essentially two-
dimensional shaped article is intended to denote a shaped article of which one of its characteristic dimensions ("thickness-height") is considerably lower than its other two ones ("width" and "length"), while an essentially one-dimensional shaped article is intended to denote a shaped article of which two out of its characteristic dimensions ("thickness-width" and "thickness-height") are
considerably lower than its third one ("length"). Otherwise said, from a
mathematic point of view, essentially two-dimensional articles have essentially the appearance of a geometric surface, while essentially one-dimensional articles have essentially the appearance of a geometric line. Thus, an essentially two-dimensional article can be viewed as a surface (with a certain length and a
certain width) differing from a geometric surface in that it has a certain non-zero thickness (typically in a direction perpendicular to the surface), said non-zero thickness being however considerably lower than the square root of the surface area developed by the surface itself and, more precisely, said non-zero thickness being considerably lower than both the length and the width of the surface itself;
an essentially one-dimensional article can be viewed as a line (of a certain
length) differing from a geometric line, essentially in that it has a non-zero "two-dimensional thickness" (typically in a plane perpendicular to the line, with a certain non-zero thickness-width and a certain non-zero thickness-height as characteristic dimensions), said non-zero two-dimensional thickness being
however considerably lower (here specifically, the terms "considerably lower", which characterize a two-dimensional thickness, should generally be understood


as "more than 25 times lower" and preferably as "more than 100 times lower") than the square of the length of the line itself, more precisely, said non-zero thickness-width and said non-zero thickness-height being both considerably lower than the length of the line itself. The geometric surface can be curved or plane, twisted or untwisted ; the geometric line can be a straight line or a curved line.
Essentially zero-dimensional articles i.e. articles having essentially the appearance of a geometric point (sometimes also referred to as "material point"), with essentially no length, no width and no height, like powdery spherical
particles of polymer or powdery spherical inorganic particles coated with a polymer (with a typical diameter of a few microns), are not shaped articles within the meaning of the present invention. Thus, within the meaning of the present invention, an essentially at most two-dimensional shaped article can be either an essentially two-dimensional shaped article or an essentially one-
dimensional shaped article.
The thickness of a shaped article of a regular or irregular volume is preferably defined as :
t = ¦V t(x,y,z) dx dy dz / V,
wherein x, y and z are the coordinates of an elementary volume dV (dV being
equal to dx times dy times dz) of the shaped article of overall plain volume V, and T is the local thickness.
The local thickness x, associated to a material point of coordinates (x,y,z), is defined as the length of the shortest straight line D including the material point of concern, which goes right through the shaped article (i.e. which goes from the
material point where D enters the shaped article to the material point where D exits the shaped article).
Shaped article (A) has a thickness t advantageously lower than 100 mm. A first preferred shaped article (A) is essentially two-dimensional [shaped article (Al)].
The thickness t of shaped article (Al) complies preferably with the
relationship :
t<(V/k2)l/3 [ which is equivalent to V > (k.t). (k.t). t ] (rel-1)
wherein V is the overall plain volume of the shaped article and k is equal to 10, t is expressed in mm and V is expressed in mm3.
The thickness t of shaped article (Al) complies very preferably with above
relationship (rel-1), except k is now equal to 100.


In addition, the thickness t of shaped article (Al) complies preferably with the relationship :
t<(S/2)l/2/k [ which is equivalent to S > 2 . (k.t). (k.t) ] (rel-2)
wherein S is the overall surface area developed by the shaped article, k is equal to 10, t is expressed in mm and S is expressed in mm2.
The thickness t of shaped article (Al) complies very preferably with above relationship (rel-2), except k is now equal to 100.
In a first preferred variation of shaped article (Al), shaped article (Al) is chosen from articles having a thickness lower than 500 (am [shaped article (Al-1)]. Shaped article (Al-1) is commonly referred to as a film.
Shaped article (Al-1) has a thickness of preferably less than 250 mm, more preferably less than 150 mm.
Shaped article (Al-1) has a thickness of preferably more than 5 mm, more
preferably more than 50 urn.
Shaped article (Al-1) complies preferably with relationship (rel-1) in
which k has been changed to 1000. Very preferably, it complies with relationship (rel-1) in which k has been changed to 10000.
Shaped article (Al-1) is preferably flexible. It is sometimes very preferred that article (Al-1) can be flexed in such a way that it can get the appearance of a parallelepiped rectangle-like volume the thickness of which is considerably
lower than its length and its width ; roughly speaking, it looks then like a "plane with an extremely low thickness".
Shaped article (Al-1) can be an uncoated film.
Alternatively, shaped article (Al-1) can be a film coated on an essentially two- or on a three-dimensional substrate. The essentially two- or the three-dimensional substrate can be notably a fabrics, a polymeric film free of polymer (P), a sheet of paper, a wood or a metal component.
An embodiment of article (Al-1) is one wherein the substrate is a metal
component.
Another embodiment of article (Al-1) is one wherein the substrate differs
from a metal component.
In a second preferred variation of shaped article (Al), shaped article (Al)
is chosen from shaped articles having a thickness from 500 mm to 5000 um
[shaped article (A 1-2)].
Shaped article (A 1-2) has preferably the appearance of a parallelepiped
rectangle-like volume the thickness of which is considerably lower than its


length and its width ; roughly speaking, it looks then like a "plane with a very low thickness". Then, shaped article (A 1-2) is commonly referred to as a sheet.
In a third preferred variation of shaped article (Al), shaped article (Al) is chosen from shaped articles having a thickness above 5000 um [shaped article 5 (A 1-3)].
Shaped article (Al-3) has preferably the appearance of a parallelepiped
rectangle-like volume the thickness of which is considerably lower than its
length and its width ; roughly speaking, it looks then like a "plane with a low
thickness". Then, shaped article (Al-3) is commonly referred to as a slab.
Shaped article (Al-3) is advantageously rigid.
In a fourth preferred variation of shaped article (Al), shaped article (Al) is a hollow body [shaped article (A 1-4)].
The thickness of the walls of shaped article (A 1-4) is advantageously equal
to the thickness t of shaped article (A 1-4).
Shaped article (A 1-4) has a thickness t of preferably at least 250 mm, more
preferably at least 500 um.
Shaped article (A 1-4) has a thickness t of preferably at most 5000 um, more preferably at most 2500 um.
A second preferred shaped article (A) is essentially one-dimensional 20 [shaped article (A2)].
Shaped article (A2) has a thickness t which is preferably lower than 10 mm, more preferably less than 250 urn, still more preferably less than 50 um, and the most preferably less than 10 (xm.
The thickness t of shaped article (A2) complies preferably with the relationship:
t<(V/k')1/3 [which is equivalent to V>(k'.t) .t .t] (rel-3)
wherein k' is equal to 10, V as above defined, t is expressed in mm and V is expressed in mm3.
The thickness t of shaped article (A2) complies very preferably with above relationship (rel-3), except k' is now equal to 100.
The thickness t of shaped article (A2) complies still more preferably with above relationship (rel-3), except k' is now equal to 1000.
The thickness t of shaped article (A2) complies the most preferably with
above relationship (rel-3), except k' is now equal to 10000.
In addition, the thickness of shaped article (A2) complies preferably with
the relationship :


t<(S/k')'/2/2 [which is equivalent to S> 4. (k'.t).t] (rel-4)
S as above defined, k'is equal to 10, t is expressed in mm and S is expressed in
mm2.
The thickness t of shaped article (A2) complies very preferably with above relationship (rel-4), except k' is now equal to 100.
The thickness t of shaped article (A2) complies still more preferably with above relationship (rel-4), except k' is now equal to 1000.
The thickness t of shaped article (A2) complies the most preferably with
above relationship (rel-4), except k' is now equal to 10000.
In a first preferred variation of shaped article (A2), shaped article (A2) has
the appearance of a cylinder-like plain volume the diameter of which is
considerably lower than its length ; roughly speaking, it looks then like a
"straight line with an extremely low diameter" [shaped article (A2-1)]. Shaped
article (A2-1) is commonly referred to as a fiber. For certain variations of shaped article (A2), in particular when shaped
article (A2) is a filament, good results can be obtained notably when shaped article (A2) consists essentially of, or even consists of, polymer composition (C).
In a second preferred variation of shaped article (A2), shaped article (A2)
is a coating coated on an essentially one-dimensional substrate, like an inorganic
fiber, a polymeric fiber free of polymer (P) or a metal [shaped article (A2-2)].
Shaped article (A2-2) has then preferably the appearance of a circular crown
surrounding a cylinder-like plain volume composed by the essentially one-
dimensional substrate, the thickness of the crown being considerably lower than
the length and the diameter of the cylinder-like plain volume.
The thickness t of shaped article (A2-2) is still more preferably less than
50 mm, and the most preferably less than 10 urn. Besides, it is advantageously lower than the diameter of the essentially one-dimensional substrate.
Shaped article (A2-2) is advantageously few sensitive to interfacial segregation and delamination failure. In addition, it has advantageously a long- term thermal stability. These good properties are usually achieved notably because of the high glass transition temperature of polymer (P).
The method for the preparation of an essentially at most two dimensional shaped article, or part of shaped article, comprising a material comprising a cross-linked poly(aryl ether ketone) according to the present invention comprises 35 the steps of:

(a) heating a cross-linkable poly(aryl ether ketone) comprising chains which comprise more than two reactive end groups selected from halogen and hydroxy I groups to a temperature of above its melting point;
(b) melting the cross-linkable poly(aryl ether ketone);
(c) forming said shaped article, or part of shaped article;
(c) maintaining it at a temperature of the melting point of the cross-linkable poly(aryl ether ketone) for a sufficient time in order to obtain said shaped article, or part of shaped article.
In a specific embodiment of said method for the preparation of essentially at most two dimensional articles, or part of shaped articles, comprising a material comprising a cross-linked poly(aryl ether ketone), the poly(aryl ether ketone) is poly(ether ether ketone). In such a case, in step (a) and (d), the temperature is of above 330°C, preferably of above 340°C and more preferably of above 345°C.


CLAIMS
1. An essentially at most two dimensional shaped article, or part of shaped article, comprising a material comprising a cross-linked poly(aryl ether ketone).
2. The article or part of shaped article according to claim 1 wherein said
article is a film, a fiber, a sheet, a slab or a hollow body.
3. The article or part of shaped article according to claim 1 wherein said
article is a film.
4. The article or part of shaped article according to claim 1 wherein said
article is a film coated on an essentially two- or on a three-dimensional substrate.
5. The article or part of shaped article according to claim 1 wherein said article is a coating coated on an essentially one-dimensional substrate.
6. The article or part of shaped article according to any one of the preceding claims wherein said poly(aryl ether ketone) is poly(ether ether ketone).
7. The article or part of shaped article according to claim 6 wherein said
poly(aryl ether ketone) is poly(ether ketone).
8. The article or part of shaped article according to claim 6 wherein said
poly(aryl ether ketone) is poly(ether ketone ketone).
9. A method for the preparation of an essentially at most two dimensional
shaped article, or part of shaped article, comprising a material comprising a
cross-linked poly(aryl ether ketone) comprising the steps of:
(a) heating a cross-linkable poly(aryl ether ketone) comprising chains which comprise more than two reactive end groups selected from halogen and hydroxyl groups to a temperature of above its melting point;
(b) melting the cross-linkable poly(aryl ether ketone);
(c) forming said shaped article, or part of shaped article;


(d) maintaining it at a temperature of the melting point of the cross-linkable poly(aryl ether ketone) for a sufficient time in order to obtain said shaped article, or part of shaped article.
10. The method of claim 9, wherein the essentially at most two
dimensional shaped article, or part of shaped article is identical to the article or part of shaped article according to claim 1.
11. The method of claim 9, wherein the essentially at most two
dimensional shaped article, or part of shaped article is identical to the article or
part of shaped article according to claim 2.
12. The method of claim 9, wherein the essentially at most two
dimensional shaped article, or part of shaped article is identical to the article or part of shaped article according to claim 3.
13. The method of claim 9, wherein the essentially at most two
dimensional shaped article, or part of shaped article is identical to the article or
part of shaped article according to claim 4.
14. The method of claim 9, wherein the essentially at most two dimensional shaped article, or part of shaped article is identical to the article or part of shaped article according to claim 5.
15. The method of claim 9, wherein the essentially at most two
dimensional shaped article, or part of shaped article is identical to the article or part of shaped article according to claim 6.
16. The method of claim 9, wherein the essentially at most two
dimensional shaped article, or part of shaped article is identical to the article or
part of shaped article according to claim 7.
17. The method of claim 9, wherein the essentially at most two
dimensional shaped article, or part of shaped article is identical to the article or part of shaped article according to claim 8.
18. A cross-linkable poly(aryl ether ketone) comprising chains which comprise more than two reactive end groups selected from halogen and hydroxyl groups.



19. A method for the preparation of a cross-linkable poly(aryl ether
ketone) comprising chains which comprise more than two reactive end groups
selected from halogen and hydroxyl groups, which comprises a nucleophilic
polymerization of i) a polyfunctional aromatic compound having at least three
reactive groups, wherein at least one of the functional groups comprises a halogen, with ii) a dinucleophile and optionally iii) a difunctional aromatic compound, wherein at least one of the two functional groups comprises a halogen.
20. A method for the preparation of a cross-linkable poly(ether ether
ketone) comprising chains which comprise more than two reactive end groups
selected from halogen and hydroxyl groups, which comprises an electrophilic polymerization of phenoxy phenoxy benzoic acid using an alkane sulfonic acid as solvent, a condensing agent, a diluent, in the temperature range of 40 to 140° C, followed by precipitation of the said poly(ether ether ketone) in water after it has achieved the desired inherent viscosity and after the removal of the acid residues with treatments with water and later with organic solvent like DMAc or DMF or with bicarbonate solution, filtering and drying it to give the cross-linkable poly(ether ether ketone).