United States Patent
`Koch et al.
`
`[19]
`
`[75]
`
`[54] PREPARATION OF
`POLYARYLENEETHERKETONES
`Inventors:
`Juergen Koch, Neuhofen; Wolfgang
`Stegmaier, Hassloch; Gerhard Heinz,
`Weisenheim, all of Fed. Rep. of
`Germany
`[73] Assignee: BASF AktiengeselIschaft,
`Ludwigshafen, Fed. Rep. of
`Germany
`[21] App1. No.: 393,793
`[22] Filed:
`Aug. 15, 1989
`Foreign Application Priority Data
`[30]
`Fed. Rep. of Germany
`3829520
`Aug. 31, 1988 [DE]
`C08G 8/02; C08G 14/00;
`[51]
`Int. Cl.s
`C08G 85/00; C08F 2/00
`528/125; 528/126;
`528/128; 528/219; 526/65; 526/66
`528/125, 126, 128,219;
`526/65,66
`
`[52] U.s. Cl
`
`[58] Field of Search
`
`[56]
`
`References Cited
`U.S. PATENT DOCUMENTS
`3.441,538
`5/1969 Marks
`1/1972 Ben
`3,637,592
`3,953,400 4/1976 Dahl
`3,956,240· 5/1976 Dahl
`4.843,131
`6/1989 Becker et al.
`4,874,840 10/1989 Becker
`4,912,181
`3/1990 Becker et al.
`
`:
`
`528/125
`528/194
`528/179
`528/125
`526/65
`328/125
`526/65
`
`FOREIGN PATENT DOCUMENTS
`1383393
`2/1975 United Kingdom.
`
`111~11I~lnllll~111
`US005081215A
`Patent Number:
`[11]
`[45] Date of Patent:
`
`5,081,215
`Jan. 14, 1992
`
`8403892 10/1984 World Int. Prop. O ..
`
`OTHER PUBLICATIONS
`"Chemical Reaction Theory-An Introduction", Stick(cid:173)
`stoffbiicherei, 3rd ed., K. G. Denbigh et aI., Cambridge
`University Press, London, pp. 1-5-et seq.
`Primary Examiner-John Kight, III
`Assistant Examiner-P. Hampton-Hightower
`Attorney. Agent. or Firm-Gblon, Spivak, McClelland,
`Maier & Neustadt
`[57]
`ABSTRACf
`Polyaryleneetherketones are prepared by a quasicon(cid:173)
`tinuous process, by Friedel-Crafts polycondensation of
`a reaction mixture containing
`A. a monomer system of
`(a)
`(I) an aromatic dicarboxylic acid chloride or phos(cid:173)
`gene and
`(2) a polynuclear aromatic having two exchange(cid:173)
`able hydrogen atoms and/or
`(b) a polynuclear aromatic carboxylic acid chloride
`having one exchangeable hydrogen atom,
`B. a Lewis acid,
`C. if necessary, a Lewis base and
`D. an inert solvent.
`The reaction mixture is subjected to polycondensation
`in a first zone, with stirring, to a viscosity of not more .
`than 2,000 mPa.s,
`then conveyed through a second,
`vertical, unstirred zone with plug flow by means of gas
`pressure, where the polyco~densationis completed, and
`is finally di~charged continuously.
`
`6 Claims, 1 Drawing Sheet
`
`4
`
`3
`
`2
`
`---1
`
`--+---5
`
`t - - - - - - - - - -7
`
`6
`
`SNF Exhibit 1020, Page 1 of 6
`
`

`
`u.s. Patent
`
`Jan. 14, 1992
`
`5,081,215
`
`4
`
`3
`
`2 1
`
`-+---5
`
`1------------7
`
`6
`
`SNF Exhibit 1020, Page 2 of 6
`
`

`
`1
`
`PREPARATION OF
`POLYARYLENEETHERKETONES
`
`The present invention relates to a process for the
`preparation of polyaryleneetherketones by electrophilic
`polycondensation in two reaction zones.
`Polyaryleneetherketones are high quality thermo(cid:173)
`plastics which have particularly good heat resistance,
`
`5,081,215
`
`2
`pressure, where the polycondensation is completed
`under substantially adiabatic conditions.
`The individual components of the reaction mixture
`are described in detail in WO 84/03892, which is hereby
`5 incorporated by reference.
`A. Preferred monomer systems A are:
`al)
`terephthaloyl
`chloride and 4,4'-diphenoxyben(cid:173)
`zophenone, which leads to a polyaryleneetherketone
`of the structure
`
`great toughness, very good mechanical properties and
`resistance to chemicals and solvents.
`Polyaryleneetherketones can be prepared by either
`nucleophilic or electrophilic substitution reactions.
`In the electrophilic polycondensation, either
`a) a monomer mixture consisting of .an aromatic dicar(cid:173)
`boxylic acid chloride or phosgene and a polynuclear
`aromatic having exchangeable hydrogen atoms or
`b) a polynuclear aromatic acyl chloride having a reac-
`
`20
`
`a2) terephthaloyl chloride and 1,4'-diphenoxybenzene,
`which leads to
`
`-o-0-o-0-o-c0-o-co-
`
`terephthaloyl chloride and 1,4-bis-(phenoxyben(cid:173)
`a3)
`zoyl)-benzene, which leads to
`
`tive hydrogen atom
`is converted in the presence of a Friedel-Crafts catalyst.
`According to U.S. Pat. Nos. 3,441,538, 3,953,400 and 35
`3,956,240, boron trifluoride in hydrogen fluoride as a
`solvent is employed.
`According to WO 84/03892, it is possible to use less
`corrosive solvents, for example methylene chloride or
`dichloroethane, if a Lewis acid, for example aluminum 40
`trichloride, preferably together with a Lewis base, for
`example lithium chloride or dimethylformamide, is used
`as the catalyst.
`This process variant avoids the use of HF and BF3,
`permits the polycondensation to be carried out at low 45
`temperatures and gives a gel-like reaction material
`which is easier to handle than the hard reaction prod(cid:173)
`ucts which are formed in the absence of a Lewis base.
`The polycondensation is carried out by a procedure
`in which the starting compounds are added in succes- 50
`sion to a stirred and temperature controlled suspension
`of aluminum chloride in the solvent. The polycondensa(cid:173)
`tion reaction leads to a pronounced increase in viscos(cid:173)
`ity.
`When the process is scaled up to the industrial scale, SS
`it is found that in many cases the reaction material is so
`highly viscous that it can no longer be stirred and dis(cid:173)
`charged from the reactor.
`It is an object ofthe present invention to improve the
`known process so that the resulting reaction material 60
`can be handled even when the procedure is carried out
`on an industrial scale.
`We have found that this object is achieved if the
`polycondensation is carried out in two reaction zones,
`and the reaction mixture is subjected to polycondensa- 6S
`tion in the first zone, with stirring, to a viscosity of not
`more than 2,000 mPa.s and is then conveyed through a
`second, vertical zone with plug flow by means of gas
`
`The aromatic dicarboxylic acid chloride and the pol(cid:173)
`ynuclear aromatic are used in essentially equimolar
`amounts, small deviations being permissible in order to
`obtain the required molecular weight.
`b) The polycondensation ofp-phenoxybenzoyl chloride
`with itself leads to
`
`-< )--0-(
`
`)--co-
`
`c) Monofunctional reagents for chain termination are,
`for example, benzoyl chloride and p-phenoxyben(cid:173)
`zophenone. They are particularly import.ant for the
`polycondensation of the monomers b) for obtaining
`the required -molecular weight; they are also used for
`stabilizing the polymers in .the melt. They are em(cid:173)
`ployed in general in amounts of from 1 to 10 mol %,
`based on the monomers a) or b).
`B. A preferred Lewis acid is aluminum chloride, and
`aluminum bromide, antimony pemachloride, boron
`trifluoride, zinc chloride,
`iron(III) chloride,
`titanium
`tetrachloride and tin(ID chloride are also suitable. They
`are used in an amount of not less than one mole per
`nucleophilic group in the reaction mixture,
`it being
`necessary to use a small excess, preferably from 5 to 30
`mol %, which is sufficient to catalyze the polyconden(cid:173)
`sation reaction.
`C. The reaction mixture preferably contains a Lewis
`base, for example an alkali metal halide, such as LiCI or
`NaCI, and polar organic compounds, such as N-methyl(cid:173)
`pyrrolidone, N,N-dimethylformamide, I-methyl-2-pyr(cid:173)
`rolide, dimethyl sulfone, diphenyl sulfone, tetramethyl(cid:173)
`ene sulfone (sulfolane), dimethyl sulfide,
`imidazole,
`benzophenone and trimethylamine. LiCI and dimethyl
`
`SNF Exhibit 1020, Page 3 of 6
`
`

`
`5,081,215
`
`3
`sulfone are preferred. They are used in amounts of from
`0.01 to 4 moles per mole of acid groups.
`D. Suitable inert solvents are: methylene chloride,
`o-dichlorobenzene,
`1,2,4-trichlorobenzene,
`1,2-
`dichloroethane and 1, I,2,2-tetrachloroethane.
`The polycondensation is usually carried out at from
`-70· to + 150· C. Advantageously, it is initiated in the
`first reaction zone at
`low temperatures, for example
`from -SO· to _10· c., and the temperature is then
`allowed to increase to, for example, - 30· to + 30· C. 10
`The entire reaction should be carried out at least under
`slightly superatmospheric pressure,
`advantageously
`above 1.1, in particular from 2 to 10, bar, in order to
`prevent escape of the resulting hydrogen chloride and
`hence foaming. This is also important in the transfer 15
`from the first to the second reaction zone. For transfer(cid:173)
`ring the prepolymer from the stirred preliminary reac(cid:173)
`tor to the downstream reactor, it is adv~ntageous if thc
`pressure maintained in the preliminary reactor is higher
`than that in the downstream reactor. It may be useful to 20
`reduce the pressure in the downstream reactor slightly
`during introduction of prepolymer into the said reactor.
`However, the pressure should not be reduced to such an
`extent that the reaction material foams.
`Mixing of the liquid and solid reaction components 25
`and the prepolymerization are carried out in the first
`reaction zone with stirring, expediently in a cooled
`stirred kettle which advantageously consists of a corro(cid:173)
`sion-resistant alloy, for example Hastelloy. The initial
`viscosity is about 0.5 mPa.s. Polycondensation is carried 30
`out in the first reaction zone until
`the viscosity has
`increased to 20-2,000, preferably 50-200, mPa.s. In the
`case of the polycondensation of terephthaloyl chloride
`with diphenoxybenzophenone,
`this takes about 15-25
`minutes from the addition of the final monomer.
`The prepolymer is then introduced directly into the
`second reaction zone. This is done by means of gravity
`and/or inert gas pressure. The viscosity during transfer
`of the prepolymer to the downstream reactor should be
`sufficiently high to prevent the aluminum chloride from 40
`settling out in the downstream reactor; otherwise a high
`molecular: weight polyetherketone will not be formed.
`It should, however, be sufficiently low to permit com(cid:173)
`plete transfer of the prepolymer to the downstream
`reactor.
`
`4
`said reaction tube has no hydraulically operated parts.
`The lower end of the reaction tube advantageously
`tapers conically (see Figure) and ends in a discharge aid.
`The latter may consist of a vertical or, preferably, hori-
`5 zontal screw unit by means of which the reaction mate(cid:173)
`rial is forced out, and a perforated disk may be mounted
`on the screw, permitting preliminary comminution of
`the reaction material. The discharge aid can, however,
`also be a star wheel or a vertical, movable piston.
`To obtain uniform product quality, in particular with
`regard to the degree of polymermaterial, the reaction
`must pass through the tube reactor with plug flow, from
`the point of entry into the tube reactor to the point of
`discharge from the said reactor. The following mea(cid:173)
`sures are advantigeous for ensuring this:
`a) Coating of the inner wall of the tube reactor and of
`the feed lines and discharge lines with a low-friction
`material which is inert to the reaction material and
`antiadhesive, . for example polytetrafluoroethylene
`(PTFE), polyvinylidene fluoride (PVDF), perfluoro(cid:173)
`ethylenepropylene (FEP) or other coatings or linings
`having appropriate properties.
`(b) Installation of an apparatus at the end of the cylindri(cid:173)
`cal area, which apparatus is preferably in the form of
`a conical or double-cone displacer or in the form of a
`perforated plate or concentric rings. This prevents
`the reaction material from flowing out only in the
`region around the longitudinal axis in the discharge
`area.
`The downstream reactor possesses, at the upper end,
`a feed for compressed gas, which has three objects:
`a) Producing an inert gas volume above the reaction
`material.
`b) Building up pressure to prevent the reaction mate(cid:173)
`rial from foaming.
`c) Moving the reaction material with plug flow to the
`discharge aid in the lower part of the reactor.
`The reaction tube is advantageously provided with a
`jacket through which liquid flows or with another suit(cid:173)
`able apparatus for temperature control.
`The mode of operation of this reactor, starting from a
`reactor already filled with prepolymer, may be de(cid:173)
`scribed as follows.
`45 A) By means of gas pressure, preferably with nitrogen,
`the reaction material is forced continuously with plug
`flow toward the discharge aid in the conicaol part of
`the reactor. From there, the reaction material is dis-
`charged by the discharge aid into a downstream
`working-up unit. There, preliminary comminution
`takes place.
`B) The volume which becomes available in the tube
`reactor is filled at regular time intervals by introduc(cid:173)
`tion of prep6lymer. In the optium case, the same
`amount is discharged continuously as is introduced
`batchwise at the upper end of the tube reactor, so that
`the amount of reaction mixture present in the reactor
`remains on average constant. The level of the reactor
`content should be such that the time from introduc(cid:173)
`tion to discharge is sufficient to achieve the desired
`molecular weight. The intrinsic viscosity (measured
`for DoS g/lOO ml in H2S04) of the polymer prepared
`should preferably be from 0.5 to 1.6.
`The amount of reaction product fed to the down-
`65 stream working-up unit can be varied in a simple man(cid:173)
`ner by changing the rotary speed of the discharge
`screw, and remains very substantially constant with
`time. Since preliminary comminution of the reaction
`
`35
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`In the simplest case, the downstream reactor of the
`second reaction zone consists of a simple vessel. In
`industrial-scale plants, however, a vertical, cylindrical, 50
`unstirred tube reactor having an l:d ratio of from 2:1 to
`10:1 is preferred, in order to be able to handle the highly
`viscous polymer in a closed apparatus and to be able to
`discharge it for further working up.
`.
`The Figure shows such a tube reactor schematically. 55
`It consists of a reaction tube (1) which contains the
`reaction material (2). A displacement apparatus (5) may
`be installed at its lower conical end. The prepolymer (3)
`is introduced batchwise from the preliminary reactor
`into the reaction tube and conveyed downward contin- 60
`uously by means of gas pressure (4). The polymer is
`forced out (7) by a discharge aid (6) and can then be
`comminuted. The tube reactor may be constructed in
`any size, and the ratio of its volume to the volume of the
`preliminary reactor is made to correspond to the ratio
`of the residence times of the reaction material in the two
`reaction zones. Since the reaction material is conveyed
`through the reaction tube by means of gas pressure, the
`
`SNF Exhibit 1020, Page 4 of 6
`
`

`
`5,081,215
`
`5
`material takes place in the discharge screw, the down(cid:173)
`stream comminution unit is relieved.
`The residence time in the second reaction zone is in
`general from 3 to 8, preferably from 4 to 5, hours.
`
`EXAMPLE I
`In a 2 I pressure vessel, 580 g (4.35 moles) of alumi(cid:173)
`num chloride are suspended in 840 ml of dry methylene
`
`6
`The resulting polymer has an intrinsic viscosity of
`1.07 (measured at 25° C. in concentrated sulfuric acid,
`0.5 g/l00 ml).
`With the aid of the apparatus described in this Exam(cid:173)
`S pIe, it is also possible to maintain continuous operation
`of the downstream reactor and working-up unit over a
`prolonged period.
`The resulting polymer has the structure
`
`-{ }-o-{ }-CO-{ }-o-< }-CO-< }-CO-
`
`chloride and the suspension is cooled to below 0° C.
`112.96 g (1.20 ~oles) of dimethyl sulfone, 162.42 g (0.8
`mole) of tereph'thaloyl chloride and 4.05 g (0.029 mole)
`of benzoyl chloride are added in succession while cool- 20
`ing. After the mixture has been cooled to < - 10° C.,
`298.41 g (0.814 mole) of 4,4'-diphenoxybenzophenone
`are also added. The vessel is then provided with a gas(cid:173)
`tight seal and nitrogen under about 3 bar is forced in to
`maintain the pressure. With slow heating, the viscosity 25
`increases to 100 mPa.s in the course of about 20 minutes.
`The temperature is then about 18° C. During this pre(cid:173)
`condensation time, the inert gas pressure in the reaction
`vessel is increased to about 10 bar.
`The volume of the prepolymer is about 1,500 mL
`By means of the applied nitrogen pressure, the reac(cid:173)
`tion mixture is then discharged through the base outlet
`valve in the course of 5 minutes and transferred to the
`downstream reactor via a pressure-resistant tube coated
`on the inside with PTFE.
`The procedure is repeated and the resulting prepoly(cid:173)
`mer is transferred to the downstream reactor at inter(cid:173)
`vals of one hour.
`The diameter of the downstream reactor is 150 mm
`and the length of the cylindrical part is about 500 mm. 40
`The volume is thus about 8,800 cm3. A double-cone
`displacer element is mounted by means of three webs in
`the transition from the cylindrical to the conical part of
`the reactor. All surfaces of the tube reactor which corne
`into contact with the product are coated with PTFE.
`A Hastelloy C4 discharge screw which is driven by
`an electric motor, has a diameter of 40 mm and dis(cid:173)
`charges at right angles to the axis of the reaction tube is
`mounted in the lower, conical part of the downstream
`reac.tor. A perforated plate having 4 mm holes and a SO
`rotating scraper is mounted at the discharge orifice of
`the screw.
`The downstream reactor is operated in such a way
`that 1,50<? ~l of reacted material are discharged per
`hour. ThlS IS the same amount as that which is intro- 55
`duced batchwise in the form of prepolymer into the
`downstream reactor.
`The temperature in the downstream reactor is 25° C.,
`the pressure is 5 bar and the mean residence time is 5
`hours.
`The discharged reaction material is worked up by
`~eans of a hammer mill, 200 lib of water being sprayed
`In to hydrolyze the polymer/aluminum chloride com(cid:173)
`plex. With a throughput of 1,500 ml of polymer per
`hour, the power consumption of the mill is 0.6 kW.
`The polymer is then freed of catalyst residues by
`repeated extraction with water and is dried under re(cid:173)
`duced pressure at 200° C.
`
`Its glass transition temperature is 175 0 C. and its melt- .
`ing point is 375 0 C.
`
`EXAMPLE 2
`In a I 1 pressure vessel, 300 ml of dry 1,2--dichloroe(cid:173)
`thane are initially taken and cooled to - 30° C. 400 g (3
`moles) of aluminum chloride, 31.79 g (0.75 mole) of
`lithium chloride and 54.83 g (0.75 mole) of dry dimeth-
`ylformamide are slowly added in succession, while
`cooling. The mixture is recooled to - 200 c., after
`which a mixture of 167.75 g (0.750 mole) ofp-phenoxy(cid:173)
`benzoyl chloride, 0.633 g (0.450 mole) of benzoyl chlo(cid:173)
`ride, 1.234 g (0.0450 mole) of p-phenoxybenzophenone
`30 and 130 ml of 1,2-dichloroethane is added dropwise in
`the course of 15 minutes. During this procedure, the
`temperature is kept below - 5~ C. by cooling. The pres(cid:173)
`sure. vessel is then closed. and nitrogen is forced in to a
`pressure of 5 bar. After about 50 minutes, the viscosity
`35 of the prepolymer has reached about 100 mPa.s. The
`prepolymer is transferred to the downstream reactor
`described in Example 1 via the base outlet valve and a
`PTFE-lined pressure tube. The volum~ of the prepoly(cid:173)
`mer is about 700 ml per batch.
`The downstream reactor is filled with the prepoly-
`mer at intervals of 2 hours. The downstream reactor is
`temperature controlled at 0° C. by means of the jacket
`through which liquid flows. After the downstream re(cid:173)
`actor has been completely filled, 350 ml of polymer per
`hour are discharged continuously at
`the lower end.
`Introduction of fresh prepolymer is continued. The
`discharged reaction material is worked up in a hammer
`mill as described in Example I. After repeated extrac(cid:173)
`tion with water, the resulting polymer is dried under
`reduced pressure. The yield is 84 g per hour.
`The polymer obtained has the structure
`
`45
`
`00-{ }-CO-
`
`and has a glass transition temperature of 165° C. and a
`melting point of 365 0 C. The intrinsic viscosity (0.5
`60 g/IOO ml in concentrated sulfuric acid at 25° C.) is 1.1.
`We claim:
`1. A process for the preparation of a polyarylenee(cid:173)
`therketone by Friedel-crafts polycondensation of a re(cid:173)
`action mixture containing
`65 A. a monomer system of
`(a)
`(1) an aromatic dicarboxylic acid chloride or phos(cid:173)
`gene and
`
`SNF Exhibit 1020, Page 5 of 6
`
`

`
`5,081,215
`
`7
`(2) an essentially equimolar amount of a polynu(cid:173)
`clear aromatic which contains two hydrogen
`atoms exchangeable by electrophilic substitution
`(b) a polynuclear aromatic carboxylic acid chloride
`which has a hydrogen atom exchangeable by elec(cid:173)
`trophilic substitution and is capable of undergoing
`condensation with itself, or
`(c) a mixture of (a) and (b),
`B. a Lewis acid in an amount of not less than one 10
`mole per nucleophilic group in the reaction mix(cid:173)
`ture and in addition a small excess which is suffi(cid:173)
`cient to catalyze the reaction, and
`C. a solvent which is inert under reaction conditions,
`wherein the reaction mixture is subjected to polycon(cid:173)
`densation in a first reaction zone, with stirring, to a
`viscosity of not more than 2,000 mPa.s and is then
`conveyed through a second, vertical reaction zone
`with plug flow by means of gas pressure acting 20
`
`8
`directly upon the reaction material, where the
`polycondensation is completed.
`2. A process as claimed in claim 1, wherein the poly(cid:173)
`condensate from the second reaction zone is discharged
`5 continuously by a conveying unit.
`3. A process as claimed in claim 1, wherein the first
`reaction zone is a cooled stirred kettle, and the second
`reaction zone is a vertical, cylindrical, unstirred tube
`reactor.
`4. A process as claimed in claim 1, wherein a Lewis
`base in an amount of from 0.01 to 4 moles per mole of
`acid group is additionally present during the polycon(cid:173)
`densation.
`S. A process as claimed in claim 2, wherein the poly(cid:173)
`15 condensate is discharged continuously from the second
`reaction zone by a horizontally arranged screw unit.
`6. A process as claimed in claim 1, wherein a mono(cid:173)
`functional reagent for blocking the terminal groups is
`additionally present during the polycondensation.
`• • •
`• •
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`SNF Exhibit 1020, Page 6 of 6