Note: Descriptions are shown in the official language in which they were submitted.
23~3 - -
This invention relates to polymers, especially
polyketones al~d polysulfones, and a process for their
manu:EactureO
In the search for organic polymers suitable for
use at elevated temperatures, many repeating units
involving diverse ccnnecting linkages between aromatic
moieties have been suggested, e,g. aromatic structures
connected by such linkages as imldes, ethers, sulfones
and ketones. Unfortunately, as potential perfoYmance
at elevated temperature has ~een enhanced, the
amenability of the polymer candidates to classical
techniques of melt fabrication for polymers has
decline~ or disappeared. More often than not, the same
decline in melt processability accompanies attempts to
produce high temperature stable polymers having an
.
elongation of at least about 50%, a necessary property
for many polymer applications, e.g~, if a polymer-
; ~ insulated wire is to be capa~le of being twisted about
itself without cracking of the,insulation.
Aromatic polyketones are known to enjoy relatively
good resistance to thermal degradation. Bonner, in
U,SO Patent No. 3,065,205, proposes the Friedel-Crafts -
ca-talyzed pol~merization of certain reactants to yield
polyarylketones, and lists as typical Friedel-Crafts
.,
catalysts ferric chloride and boron trifluoride~ The
two basic reaction~ tauyht by this patent can be
summarized as follows-
.
~ 2 -
.
'' ~.
1) n(HR-O-RH) -~ n(Cl-A-Cl) ~nHCl + H(R-O-R-A)n ~1 .
and
2) n(HBH) ~ n(Cl-A~Cl)--~ nHCl -~ Cl(A-B)nH
where HBH is a polynuclear aromatic hydrocarbon, e.g.,
naphthalene, ~-O-RH is a diaromatic ether, e.gO,
dlphenyl ether, and Cl-A-Cl is a diacyl chloride, e.g.,
terephthaloyl chloride or
- 2a -
3~3, : `
pho~geneO When phosgene and diphenyl ether are reacted9 the
re~ulting poly~er will compri~e repeating unit~ of the structure:
~30~C - ' '
~,
~ha ~ame repeating u~it i~ ~tated in ~ritish Patent
~o ~, 971, 227 to arise from the sel*-c:onden~ation o~ diphenyl
ether-4-carbonyl chloride~ and ~rom the reaction of diphenyl
ether with diphenyl ether 4~4l-dicarbonyl chloride.
A dif:~erent approach 1~ taken by ~arnh~m and Johnso~
in ~riti~h Patent No. 1,078,234. ~er~9 polyarylethers ~re
produced by reaction o~ a dialkali metal salt o~ a dihydrlc
phenol with a dihalo benzenoid compound. The dihydric phenol
may contain a ~eto group - thu~ 494'~dihydro~y benzophenone
i~ ~tated to yield a polyarylether polyarylketone (~ee~ for
- e~ple s ola~ 1 5 ) .
S~ther improved method~ for making polyaryll~etoxle~
h~ve been proposedO For example, ln ~.,S. Pa~ent~ ~o~.
3~441,538 and 3,4429857 there i~ su~geæted the u~e OI ~droge~
fluoride/boro~ tri~luoride catalysis, a cataly~t æy~tem taugh~
in =~
~opchiev et al, Pergamon Pre~ (1959~, pO 122, ~_~
2401 (1961); and I & :6 ChemO 4~, 746 (1951~. ~ further
:~ ~uggesbion ~or a~ improved proces~ ~or ~ynthe~ising polyaryl-
: ~ ~ ketone~ iæ di~cloæed in ~3ritish Pate~t No., 1 ,08~,û210
.
: . Bri~ish Paterlb ~o~ 1,,086,0 1 di~clo~e~ the ~iedel-
;: 25 ~ Cra~t3 co~de~atlon polymerization o~ diacid h~lide~ with a
. . . . . .
,
second compound contai~ing a1; lea~t two displaceable aromatic
~lly bound hydrogen atoms~ pre~erab]y -the diacid hallde ~nd
the ~econd compound being present in substantially equimolar
amo~nts; or of a single compound cc)ntaining both an acid
halide group and at least one displaceable aromatically
bound hydro~en atom~ It l~ ~urther disclosed that molecular
weight may be controlled by u~i~g no~-~toichiometric amounts
o~ the two compou~ds or by adding a third component which
i~ mono~unctional under the conditions o~ the reaction~
Monoacid hal~des are me~tioned a~ examples o~ suitable
mono~unctional molecular weight control agent~
Br~tish Speci~ication No. 17109,842 discloses the
polymerization reaction o~ aryl disul~onyl ha:Lide~ with CO
pound~ contai~ing at least two di~placeable aromatically
bound hydrogens. I~ all the examples o~ this patent 9 a~
i~ those o~ 1,086,021, the proposal is either o~ e~uimolar
amoUntB 0~ electrophile and nucleophile or o~ an excess o~
~ the electrophile (i.e~ ~iacid halide). ~hi~ patent ~urther
propo~ the quenching o~ residual sulfonyl chloride ~roup~
by po~t polymerization addition o~ ba~e~ ~uch as aniline,
80dium ~arbonate or diphenylether ~ince re~idual sul~onyl
chloride groups on the pol~mer chains are stated to cause
the product~ to ~uffer from rl~ing vi~cosity when moltenO
I~ U~. PateD~ No~ ~593~400 there is proposed the
preparation ~ polyarylketone3 of mean inherent vi~co~ity
(Oot % W/Y in ~ul~uric acid~ 0~8 to about 12650 ~he inhere~t
v~8co~it~ and molecular weight are controlled by the u~e in
~ppropriate quantitie3 and reaction condition~ o~ selected
~ucleophilic age~t~ who~e reacti~ity to acetylation ~rela-tive
,
- . .
to a benzene reactivity of 1) is greater than about 150~
The use of nucleophile~ a~ molecular weight control
age~t~ in pol~merizations o~ thi,s type ig advantageous ~ince
it has been ~ound that othel~ise, in aclditio~ to the problem
oP melt in~tability (re~ulting ~rom the presence o~ e~ces~
~lectrophile ~hich in turn results in re~idual acid halide
polymer chain end group~) the presence o~ a~ e~cess o~ acid
halide groups ~i.e~ 9 electrophile~3 during polymeriza~ion
leada to the formatio~ o~ branched chain pGlymers resulting
~rom ortho~acylation of nucleophilic interior segments (~uch
. as diphenyl ether moietie3) in a polymer chai~ by the
te~minal ac~d halide group~ o~ neighbori~g cha~ns. It i~
believed to be the case that ~rhîle numerou~ sites on
the nucleophile are still available linear ohain building
~ill occur but once ~uch sites become low in concentration
the ordinarily much ~lower acylation reaction at the ortho
position becomes significant. This problem has been discussed
~ ~ngeloS et a (~OS~ Pa~ent No. 3,767,620) whlch describes
the formation o~ 9-phenylenexanth-hydrol re~idues
` ~ ~
.. ~0~
.
t~rough ortho acylation durlng the preparation o~ a polymer
ha~ing the repeatin~ structural ~orm~la~
~ 5 -
.
3'~3
~3~C13
o ~ .
Such a residue i~ ~ormed by the reactio~ o~ a diacyl hallde
wl~h diphenyl ether such that at least some o~ the diacyl
halide acylate~ diphenyl e-ther residues in each ring ortho
to the o~ygen atom ~because, vlrtua:Lly all the l~ara pos~tions
are already blvcked by prior acylatio~). Such ~ortho
acylated moietles are indiçated as ~eading to thermal
in3tability~ specificallyD impaired melt processability~
Such deg~adation oan be reduced by h~droge~ation ~reduction3o~ the polymer, ~or example, ~lith ethanol and hydrochloric
acid, formic acid or pre~erably triethyl sila~e in homogeneous
acid media~ to give the much more stable 9-phenylene~lthene
. reeidueO ~hi~ reduction i~ said to lead to products of
lighter color and much improved melt stability due to the
re~oYal o~ the hydro~yl group and its replacement b~ a
- h~drogen atom~
Treatment o~ the abo~e branched polymer~ dlssolved
1~1 aic~Loroacetic acid~ with,trl~thyl silane is also recommended
b~ Agolino i~ U.S~ Patent ~o~ 3~668~057 a~ a mean~ o~
~tabil~æi~g branched chairl residue~0
' 0~ course9 if as proposed in ~.S. Patent ~oO
3~59~ 9 400 the polymerization i~ carried out with the
~ucleophilic agent in exce~g a~d~or molecular ~eight control
~ fected wi~h a nucleophilic compQund, then there i~
~n e~cess o~ ite~ and the above-mentiQ~ed branching
~o
reaction will not occur/the ~ame deleteriou~ extent.
'
flowever, it has now ~een disco~ered that when -the term-
inal yroup on either or both ends of each polymer chain is a
phenoxy (or other nucleophilic) moiety having a para position
available fQr reaction then, in highly acid media such as the
preferred hydroyen fluoride~boron fluoride mixtures, a, hereto-
fore unknown, branchIng reaction occurs. It is believed that
such branchin~ results from the reaction of the phenoxy (or
other nueleophilic) groups (presumably activatedr i.e.~ proton-
ated by the acid medium~ with carbonyl groups in the polymer
itself leading, it is believed/ to the formation of trisaryl
carbonium salts. Irl addition to the deleterious effect of
branching per _ on processabilityr such salts are thermally
very unstable and lead to degradation and discoloration in
the polymer when molten.
As disclosed in copendiny Canadian Application No.
258,689, filed August 9/ 1976, treatment of the polymerized
reaction media with certain bases before isolation of solid
polymer substantially improves the thermal stability of polymers
prepared by Friedel-Crafts condensat;~on polymerization through
a controlled decomposition of ketonic and other complexes
formed with the catalyst. However, this post-polymerization
treatment does nut stop the formation of branehed polymer chains
by or-tho acylation. Moreover 7 this treatment does not prevent
the herein-above mentioned protonated phenoxy group branching
reaction catalyzed by strong acid which takes place concurrently
with the polymerization reaetion itsel:E and can continue as long
as the polymer is in a strongly acid medium.
3 j`
~hu~ the need ~till exist~ ~or a method of preparing
polyarylketones and polyaryl ~ul~ones by a Friedel-Cra~t~
condensation ~olymerization reacti.on that yield3 linear~
~nbranched products o~ reproducibl.e molecular wei~ht, stable
and pr~dictable melt vi9eosity 7 and enhanced stability in
highly acid solutions~ ~he term "acylation" as used in
the in~tant applica-tion connotes the reaction in acidic
media o~ the moiety ArCO~ or ArS02 with an aromatic nucleo-
phile, Ar representing the residue o~ a protonated monomer
or a ~blymer chain which is con-tinuing to undergo polymeriza-
tion (chain growth) by means o~ the acylation reaction.
The term acid halide there~ore connotes any reactive species
formin~ the moièty ArCO~ or ArS02 under ~riedel-Cra-ft~
reaction conditions. Common example~ include Ar~COCl, Ar-COOH
~nd .Ar-COOR and the sul~onyl analo~ues ~hereof.
The pre~ent invention provides a polymer~ ~hich
compri~es repeating units of -the formula
~ M - Ar ~ B - Ar' ~
in which - M and - ~ - which may be the æame or di~erent
each represents - CO ~ or $0~ -, Ar repre~en-ts
or ~ ~ ~
in ~rhich ~ ~ repre~ents CO -, S02 ~ nHCO -, a
covalent bond or - ~ , wherein ~ ~ - represent~ - O -~
S ~ phen~leneo~y~ - O - Ar ~ O -~ or CR2) wherein each
R9 which may be the ~ame or different, represent~ hydro~eng
an alkyl or ~luoroalkyl group, preferably con-taining from 1
to 10 carbon atom~ 9 an un~ub~tituted phenyl group or a phenyl
.
~ 8 ~
group ~ubstituted by an elec-tron withdrawing group 9 and Ar'
represents
~ T ~ ,
the end groups o~ the polymer being ~ormed from a nucleo~hilic
or elec-trophilic capping agent~
Preferably, the alkyl or fluoralkyl groups that may
constitute R contain from 1 to 10 carbon atoms~
~he repeating ~lits in a given polymer advantageously
c~nsist essentially of repeating unit~ of the formula
~ M - Ar - 3 - Ar' ~
a~d the po~ymer i,s advantageously substantially linear and
advantageously is a homopolymer. The polymer may, however,
contain al~o units that are not a.s specified~ sv.ch a(lditional
or
units being either of unrelated structure/o~ structure deri~ed
from a unit -~ M Ar ~ ~ ~ Ar~ -~ but being -trivalent
or o~ other higher ~alency. The polymer may also contain
units of two or more identities represented by the general
for~ula ~ Ar - 3 - Ar' -~ in combination with other
unrelated repeating units. Pre~erably, when Ar~ is
~ T ~
and - T - represent~ 0 - Ar - 0 ~, the Ar ~egment o~ the
T moiety is dif-ferent from that of Ar in the
M ~ Ar - ~ - Arl ~ unit.
The nucleophilic capping agent is of the general
foxmula
~Ys
.
., .
_ g _.
, :
w~lerein - X ~ repre~ents a covalent bond~ - O ~ ~ S -,
or ~ CR2 - t wherein each R, which may be the same or di~eren-t~
has the meanin~ ~pecified above (prefera~ly - X - repre~ents
a covalen-t bond or - O -) and ~herein Y represents - CN,
- NO2, - CO ~ ~ S2 ~ ~ or, provided X i~ a covalent
bond, hydrogen~
The electro~hilic capping agent i5 of the general
~ormula Ar"COZ or Ar"SO~Zs wherein Z represent~ OH, halogen
~pre~erably chlorine or fluorine) or OAlk, wherein Alk
represent~ an alkyl group 9 preferably an alkyl group with
up to 10 carbon atom~ 9 and wherein Ar" repre~ents phenyl,
nAphthyl, biphenyl 7 ter~henyl, or phenoxyphen~
with at le~t ore electron withdrawing grbup on the phenoxy
moiety, preferably with ~uch a group at the ~ara po~itionO
The Ar" radical may otherwise be unsubst}.tuted but i~ pre~era'ol.y
~ubst~tuted by at least one electron withdrawing group~
A~ ~lectron withdrawing group~ halogeno, nitro and cyano
are pre~erred.
. Mi~tures o~ two or more nucleophilic or electro-
philic capping agents may be employed.
~he polymer may have all its end groups ~ormed
~rom electrophilic capping agent or all from nucleophilic
capping agent, or ~o~e from electrophilic and ~ome from
mlcleophilic capping agent. In ths preferred ca~e, ~here
the polymer i~ linear 9 each chain may have both end group~
~ormed ~rom the electro~hilic~ or nucleophilic 9 or may have
one end group ~ormed fro.~ electrophilic and the other from
nucleophilic, capping agent, according to the polymerization
reaction em~loyedO
_ 10 --
~3
I-t will be realized by those skilled in the art
that, although in most instances polymer chains have
two ends (i.e., are linear), in some circumstances,
as for example, ~o produce melt processable polymers
with high melt strength, it may be pre:Eerable to provide
polymers having chains with three or more ends, i.e.,
with long chain branches and that, in such circumstances
the present invention contemplates capping a]l t.he ends
of such molecules even though the term "double" or
"doubly" capped is used. '
The present invention also provides a process for
the manufacture of a polymer, by Friedel Crafts
condensation polymerization of ~ither
'(I) at least one first monomer containing diacid
halide groups and at least one second monomer
containing at least two displaceable aromatically bound
hydrogen atoms in the presence of from about 0.002
-- molè to abou~ 0.10 mole of nucleophilic capping agent
per mole of said first monomer if said first monomer
i5 in excess, ~rom about 0.002 mole to about 0.10 mole
of'electrophilic capping ayent per mole of said second
monomer if said second monomer is in excess, or from
about 0.001 to about 0O05 mole per mole of said first
monomer of each of electrophilic and nucleoph.ilic
~5 capping agent i'f said first and second monomers are
present in substantially equimolar quantities, or
(II) at least one'monomer having at leas-t one acid
halide group and at least one displaceable aromatically
bound hydrogen atoms, in the presence of ~rom about
vg~;;~ , .
0.001 mole to about 0.05 mole per mole of monomer of
each of nucleophilic and electroph:ilic capping agent,
wherein the nucleophilic capping agent is of the
formula
~ X ~ ~
and the electrophilic capping agent is of the general
formula Ari'COZ or Ar"S02Z, wherein Ar", X,Y and Z
have the meanings specified above.
The novel double capping process of the present
invention provides double capped polymers which have
excellent high temperature stability properties and
which are melt processable especially extrusible
product suitable for uses such as wire and cable
insulation. Advantageously, the polymer chain length
is within the range of from about 5 to about 500,
preferahly about 20 to about 300. Additionally, the
polymers of the present invention are fabricable by
conventional in~ection moulding techni~ues. Addition- I -
ally, these polymers are substantially free from
I
uncontrolled chain branchin~, controlled chain branching
may be achieved as described below.
The polymers produced by the process of this
invention are characterized by light color and excellent
thermal stability. In addition, they form stable
solutions even in highly acid media such as hydrogen
fluoride/boron trifluoride mixtures. Furthermore, the
solutions of the polymers according to the invention
in sulfuric acid are light in color, the solutions of
correspondin~ poly~ers prepared otherwise tllan by the
'.
12 -
invention being highly colored. Moreover, as these
polymers are essentially inert to further reaction
with either electrophilic or nucleophilic reagents
any residual polymer left in solution in a reactor
(for example on the walls of the reactor~ after
12a -
3 j
~ompletlon of one polymerization does n.o-t ha~e to be washed
out before commancement of another polymerizatlon. In prior
a~t processes residual polymer must be completely removed
~rom the reaction apparatus before fur-ther polymeri~ation is
carried ou-t, since its presence results in the production of
ve~ high molecular weight portions in the product of such
~urther polymeriæation. ~urthermore 3 as pre~iously no-ted,
polymer solutions produced by prior art processes have an
undesirable tendency to increase in molecular we-'Lgh-t o~ storage.
It is appropriate in order to ~acilîtate a *uller
understanding o~ the present invention to distinguish between
terms which are ~requently and generally erroneou~ly used
interchangeably in the prior art pertaining to ~riedel-Crafts
ca~alyzed polymeri~ationsO The term "quenching agent"
denotes a compound, usually a ~ewis ba~e (nucleophile),
~hich is added, almost in~ariably in very substantial exce~s,
to a po~ymerization reaction mixture after completion o~ the
polymerlzation reaction to react with the polymer end group~
~ -- catalyst comple~ so tha~ -the polymer molecule i5 substantially
less likely to undergo f~ther undesirable reactio~ Such
roaction is caused b~ reac-ti~e polymer end groups chemically
attacking on neighboring molecules with which the polymer
mol~cule comes in contact during subsequent proces~ing or
u~e9 Molecular weight control~ in contradistinction~ is
: 25 ge~erally e~ected by having, during~ and pre~erably ~rom
: the ~tart of 9 polymerization~ a molar exce~ o~ either the
~ucleophilic or the electrophilic difunctio~al reactant or
by adding, at any time before polymerizatio~ i~ complete,
a ~ucleophllic or electrophilic reagent which i~ mono~unctio~al
under th~ polymeri~ation reaction co~ditlons and which
thereby serYes a~ a chain terminator. ~uch monofunctio~al
~ 13 ~
~23~3
chain termination agent~q are, o~ course, ~lso use~ul when
e~fecting polymeri~ation usin~ a monorner h~ing both elec-tro-
philic and nucleophi:!ic moieties on the same molecule~ It
is, o* course, apparent that a quenching agent can sui-tably
S be used in conjunction with a mo]ecular weigh-t control agent.
A cappin~ agent 9 which can b~ either electrophilic
or nucleophilic 9 serves a di~ferent ~unction from either a
~uenching or molecular weight control agent. It~ purpose
is to form the groups at all (or both in the ca~e o~ a linear
molecule) ends of the polymer molecul~ and thereby cause
the end groups of the polymer molecule to be at least a~
resistant to chemical attack as the remainder of the molecule.
Its primary function is not to stop the polymerization and
in fact, unlike a quenching agent, it may be present in the
polymerization mixture throughout the polymerization reaction.
It should be noted that compounds which function as cappin~
agents, as above defined~ can under some circumstances serve
the ~unction of molecular weight control or, if adde~ in
- ~ large excess~ contrary to the teaching o~ the present lnvention~
can in some in~tances quench the reactionO However, the
pr~or art has in~ariably u~ecl either an electrophilic or nucleo-
philic molecular weight con-trol agent 1mder conditions which
result~ in the polymer ~olecule being reactive io~o7 uncapped
a~ herein de~ined, at at lea~t one end. ~o~ e~ampleg British
Patent NoO 1,387,303 contains a discu~sion o~ -the use of so-
alled capping agents in connection with polymerization
reactions analogous to those described herein. However~
it ~hould be noted that 9 in the conte~t o~ that patent~ the
~o~call~d capping agent~ were ln ~ct molecular weight control
P3
agent~ ~unc-tioning exclu~ively a~ 3uch and not a~ true cappi.ng
agents as de~cribed in the instant speci:~ication. In f2ct,
such ~rior art a~ents could not in ~act achieve -t.he objec-tive~
of the pre~ent inventiorl when used as described in said U.~.
pate~t~ Indeed~ the nature and significance o~ double
capping as disclo~ed and claimed herein was not appreciated
at -the time of said UoK~ patent~
The present invention contemplates the use of a
capping a~ent to provide a polymer molecule which i~ unreac-tive
and resi~tant to chemical attack at both ends o~ the molecule.
Use of a quenching and/or rnolecular wei~ht con-trol ~gent as
hereinabove defined in conjunction with a capping agent
provides no useful e~ect and c~n in ~orne circumstances be
deleterious. The distinction between quenching agent~ and
t5 capping ~gents may be clarified by considering the -former
as reducing the tendency of the polymer to attack other
molecule~ including nonomer or oligomer (which are less
~ reactive than the polymer), while the latter increases
the polymer'~ resistance to attack by species more reactive
than the polymerJ Since a quenching agent may only be added
after the enti.re polymeriza-tion is complete, the use o~ a
molecular weight control agen-t without a capping agent means
tha-t in any polymerization reaction mixture there will be
present before quenching substantial numbers o~ "completed"
- 25 molecules whose ~row-th has been stopped by the molecular
weight control agent but which are nonetheless ~u~ficiently
u~stable that they are under.going degradation~ Since other
molecule~ arel o~ cour~e7 ~till undergoing ~olymerization,
it i~ impractical to deactivate these completed molecule~
.
- 15 -
.
by adding a ~uenclling agent~ Thus/ when the polymeriæa-tlon
reaction is finally quenched~ ît will cont~lin a signi~'icant
proportion of molecules whose chain growth was com~leted
early on and which thereafter degr,aded. 'rhis problem is
particularly acute when highly reactive catalysts such as
HF-~F3 ~re utilized. This is one of the problems unex~ectedly
~olved by the present invention~
With this background 9 the use o~ the pre~ent
- invention to provide controlled branching may be more readily
understood. I~ ,the polymerization uses monomer ha~ing a
diacid halide and a displaceable hydrogen9 i~e.~ a type II
polyrnerization, a molecular ~eigh-t control agent having
more than t~lo chain initiation sites is employed 3 branching
will occur, and the nature ~nd molar percen-ta~e of capping
" agent will be in~luenced by the number of initiation sites~
~or example, i~ the molecular weight control agent
is ~ nucleophile, the end capping agent should be an electro-
phile, and be present in a pe.rcentage rnolar ratio equal to
the number o~ initiation sites~
Branching ma~r also occur i~ an electrophilic
capping agent having multiple ~unctionali-ty is used~ since
thi~ may cap several growing chai.ns; if there is u~ed a
molecular w~ight control agent in combination~ then if the
molecular weight control agent initiates on one side onl~y~
and is otherwise unreacti~e a single branching site results
i~ each molecu].e~ which is pre~erred~ Alternati~ely,
whiGh is not preferred~ the molecular ~eight con-trol agent
i~ polyfunctional~ and can initiate on one side but is still
reactive on the other9 and much branching wi.ll OCCUr9
...
possibly leading to unde~sired ~e7ation7 i.-~ a poly~unction.al.
capping agen-t is used~ In this case, it is a-lvantageou~ to
use both a mono~unctional cap~ing agent and a polyf~mctional
cappihg a~ent~ wi-th the ratio o-~ t;he concentration of the
mono~unc-tlonal cap ing a~ent to that o~ the pol~T~unctional
capping agent being equal to the f`unctionali-ty of the latter.
If the molecular ~eight control agent is electrophilic, the
capping a~ent ~hould be nucleophilicO
I~ the polymerization is a q'ype I pol.y~erization~
similar considerations apply, except tha-t both the capping
agent and the molecular wei~ht control agen-t will be
nucleophilic if the electrophile monomer is in excess; and
vice versa.
It will be appreciated, howe~er, that although the
ln~ention may be employed to provide polymer~ having controlled
branching, the pre~erred products of the in~entio~ are
~ssentially linear polymers; the advantages o~ the process
of the in~ention including the reproducibili-ty o~ the resulting
polymer, and the ability to produce a polymer o~ desired
chain length and hence inherent ~iscosityc
~ ~'1 `-
The polymers with which the present invention is
particularly concerned include polyaryl ketones
comprising repeating units of the structure: ¦
O ,
C~ ......
i.e., poly(benzophenone ether). As especially
preferred, there may be mentioned homopolymers and
copolymers having such repeating units and having a
mean inherent viscosity within the range from about
0.8 ~o about lo 65. Such polymers and the preparati.on
thereof are disclosed in British Patent No. 1,387,303.
Secondly, there may be mentioned aromatic ketone I ;
polymers having the repeating unit: I
~ '' '' ' ' O=C~ ~
~ ~ ~ C- and ~ ~
=f ~ O ~
_ r
and especially homopolymers o ~-biphenylyloxybenzoyl
monomers and also copol~mers thereof incorporating
: minor proportions of corresponding o-comonomers,
polymers having a mean inherent viscosity between
about O.5 and about 107 being particularly preferred.
Analogous polymers and the manner of thelr preparation
are described in UOS. Patent No. 3,593,400.
The preaent invention also advantageously provide,s
the sulfony~ analogues of the a~ove-indicated polyaryl
ketones aDi~ the other polymers described in U.S. Patents l-
. ~
18 -
,
.
.. .. .
3~
~os. 3,441,538, 3,442,857, 3,321,449, and Briti~sh
Patents 971,227 to Goodman et al and 1,016,245 to
Jones, to the disclosures of which the reader is
referred to avoid unnecessary enlargement of the
present specification, and corresponding processes
for their manufacture.
Particularly useful solvents for use in such
polymerizations include nitrobenzene, o-dichloro-
benzene, sym-tetrachloroethane, methylene chloride,
mixtures of any o~ the foregoing, and also anhydrous
hydrogen fluoride. The common Friedel-Crafts catalysts
can suitably be employed in the polymerization process
including, for example, aluminum chloride, aluminum
bromide, boron trifluorlde, hydrogen fluoride, ferric
chloride, stannic chloride, indium chloride and
titanium tetrachloride. Aluminum, indium and ferric
chlorides are preferred ca~alysts and mixtures of
,, hydrogen fluoride and boron trifluoride are particularly
preferred.
The amount of, for example, the preferred catalysts
such as aluminum chloride or boron trifluoride will
ordinarily be at least one molar equivalent per carbonyl
or sul~onyl group of the monomeric reactants. In the
case of ferric or indium chloride less than a molar
equivalent i5 ordinarily used.
The polymers with which the present invention is
concerned are prepared b~ condensation polymerizationO
The condensation polymerizations used in the instant
invention are of two types~ In type I there are two
" , .
- 19-
~ '
3~3
monomeric starting materials, a first monomeric
reactant which is an electrophilic reagent, and is
generally a diacid halide, and a second monomeric
reactant containiny at least two displaceable
aromatically bound hydrogen atoms, a nucleophilic
reagent. If [EE7 is the molar concentration of the
electrophilic reagent and ~N~i.s the molax
concentration of the nucleophilic reagent and EE is
in excess, then the molecular weight, MW, of the
resulting polymer iR given ~y the formula:
[EE~ ~ [~N~
MW = ~ ~,c w
~E~ [N~ 2
where w is the molecular weight of the repeating unit
(i.e~, the EENN residue?-of the polymer.
Thus, use of an excess o~ EE effects molecular
weight control. Conversely, if NN iS in excess to
r ~ control molecular weight, the molecular weight is
equal to:
[~ ~ [EE~
_ _ - x 2
~NN] -- [EE]
~ If EE is in molar excess then the polymer chàins will
20 tend to have acid halide end groups which,as is well
known to those skilled in the art, readily react
further leadin~ to branched polymer chains and
instability of the polymer w~en molten.
- 20 ~
~1 ,
It has been unexpectedly discovered that when ~N
is used in excess in an effort to effect molecular
weight control and NN contains phenoxy ~roups or
groups similar in reactivity to acylation -to a phenoxy
group,which groups will be at at least one end of the
polymer chain because of the excess of ~, then
reaction of these end groups with the ketone catalyst
complex during or after polymerization tends to occur , -
so as also to cause branching, it is believed, through
the formation of trisaryl carbonium ion salts.
Furthermore, it has also been discovered that
molecular weight control through the addition of
monofunctional molecular weight control compounds to
a stoichiometric mixture of the starting materials
will not avoid either of the above problems as, ~
depending on whether the monofunctional agent is an~ ~`
electrophile or a nucleophile, each polymer molecule
- . will have an electrophilic or a nucleophilic group
respectively at the end of the polymer molecule
distant from the weight control agent residue which end
group can react further an~ cause chain branching.
The molecular weight Q~` the resultant polymer is given
by the formula:
Cc~ ~ w , . '
~ MW = - _ where [C~ = r~N~ = [E~ and
~ ~ ~:
wherein [T~ is the molar concentration of molecular
wei~ht control agent used, and w is the molecular
weight o~ the repeating unit of the polymer~ It is
thus apparent that molecular weight control for the
polymer in a type I reaction by use of excess
nucleophilic monofunctional molecular weight control
compound does not in any way address or solve the
problems of polymer stability to which the present
invention is directed. I
In the other type of polymerization (type II)
only one monomer, having both an acid halide group
and at least one aromatically bound displaceable
hydrogen is usedO If the molar concentration of th'e
monomer is [EN] and a monofunctional molecular weight
control agent is use~ -then the molecular weight of the
polymer is given byo
.
~EN~ x w
- M~ = ~ ~ ,` '
[T~
wher~ln in [T] and w are as defined above. Again,
use of a monofunctional a~ent for molecular weight
control suffers from the disadvantage that at least
one end of each polymer molecule is terminated either
by a reactive nucleophilic or electrophilic group
~hich can serve as a branch initiatorn
Accordîngly, the instant invention provides
Friedel Crafts condensation polymers whose molecules
are capped at both ends by groups which do not sPrve
as ~ranch initiators under polymerization conditions.
For a Type I condensation polymerization either
the electrophile or the nucleophile can be present in
.~ ' ' .
_ 22 -
.
f.~ 3
excess or both can be present in equimolar amounts.
In the first and second cas~s the molecular weight
s controlled by the excess r~a~tant, as above
indicated. In the first case, a nucleophilic cappiny
agen-t will effectively cap both ends o-f the polymer
chain. In the second case an electrophilic capping
agenk will cap both ends of the polymer molecule. In
a Type I polymerization, when equimolar amounts of
el~ctrophile and nucleophile are present or in a Type
II polymerization both an electrophilic and a
nucleophilic capping agent are added and the polymer
chain is capped with the nucleophilic cap at one end
and the electrophilic cap at the other. A further
advantage of the present invention is that under such
circum~ ances the capping a~ents will serve the
additional function of molecular weight control agent.
The el~ctrophilic polymer end cap for the
polymers produced in accordance with the instant
invention will have the structure Ar"CO- or AR"$O2-
wherein ~R" is as previously defined for the
electrophilic capping agentO The nucleophilic polymer
end cap will have the structure:
I
I
~o~ 0~ ~50~ 1
wherein Y and X are as previously define~ for the
nucleophilic capping agent.
Preferred ratios of ingredients in accordance
with the instant invention for type I polymerizations
are as follows~
23 -
~ '
Case a [EEl ~ ~N~
Molar fraction of difunctional electrophile [EE] : 1
Molar fraction of difunctional nucleophile [~N~ a
Molar -fraction of nucleophilic cappirlg agent 2a
Case b [MN~ [EE~
Molar fraction of difunctional electrophile [EE~: 1
Molar fraction of difunctional nucleophile [NN~ a
Molar fraction of electrophilic capping agent: 2a
Case c [NN~ = [EE]
Molar fraction of difunctional reagents (EE ~ NN)
Molar fraction of nucleophilic capping agent~ a
Molar fraction of electrophilic capping agent: a
.
Note that in cases a and b the capping agent may be
added at any stage of the polymerization, including
after polymerization is complete, and no separate
molecular weight control agen~ is necessary. In case
c, one of the capping agents functions also as a
moleaular weight control agent and therefore is
preferably added early in the pol~erization, most
preferably at the beginning of the reaction. The other
capping agent in contradistinction can be added at any
time. It will preferably be electrophilic but can b~
nucleophilicu Preferably, in all three cases, the
capping agent~s) are added at the begiIming of or early
in the course of the polymerization D
For a condensation polymerization of type II,
as in case Ic, the objectives of the inventions are
attained by adding about equal molar fractions of both
electrophilic and nucleop~ilic capping agents~ Under
- ~4
~lZ3~3
these circumstances, a separate molecular weight
control agent is not required. The ratios of
ingredients for a type II condensation are:
Molar fraction of Type II monomer 1
Molar fraction of nucleophilic capping agent a
Molar fraction of electrophilic capping agent a
In practice it is fre~uently difficult to
select precisely the same amount of each capping
agent, but it is found that extreme precision is not
required. It is preferable, where precise equivalence
of electrophilic and nucleophilic capping acJents
cannot be provided, to use a very slight exce~s of the
nucleophilic gent.
For both Type I and ~ype II reactions, ~he
lS numerical value of a will preferably vary from akout
0.001 to about 0.05, preferably 0.002 to 0,01 based
on a value of 1 for the monomer, as above indicated.
As hereinbefore indicated, thè capping agents
utiliæed in the practice of the present invention can
20 be either nucleophilic or electrophilic. ;~
Preferred nucleophilic capping agents include
biphenyl, 4-phenoxy benzophenone, or an equimolax ;
mi~ture of diphenyl ether and b2nzoic acid or a
derivative -thereof which ~orms 4-phenoxy benzophenone
in situ
~ ..
Preferred nucleophilic capping agents include
benzoic acid, benzene 9~foni~ acid or the corresponding
acid halides.
The polymers of the present invention preferably
.
- 25
3~ 1
have viscosities ranging Erom about 0.5 to 200 and
containing from about 5 to about 300 repeating unitsO
As is apparent, ~oth horno and copolymers can be
prepared in accordance with the teaching of the
instant invention by using a l~xture of electrophilic
and/or nucleophilic bifunctional monomers and/or a
mixture of monomers of the EN type.
The following examples, in which "Te~lon" and
"Waring" are trade marks, illustrate the invention.
All parts are by weight and temperatures are in C
unless otherwlse noted. Throughout, mean inherent
viscosity is determined according to the method of
Sorenson et a , Preparative Methods of Pol~mer
Chemistry Interscience (1968), p~44 [0.1 g pol~mer
in 100 ml. soln. of conc. H2SO~ at 25 C~. Electronic
spectra of polymer solu-tions were determined with a
Perkin-Elmer 450 spectrophotometer using silica cells
having a 1 cm path length. A polymer sample of 0.02
-to 0.05 g was dissolved in 5~00 ml of dichloroacetic
acid at 150 -160 ~y agitating the sample for 15 to
20 min. The solution was recorded against a
dichloroacetic acid blank. The absorbance reading
obtained at 495 nm was divided by the s~lution
concentration in grams per milliliter to give an
absorbancy index value (As) which is a measure of
branched sites in the polymer.
EXAMPLE 1
BRANCHING DUE TO PHENOXY END GROUPS INTERACTING WITH
CARBONYL LINKAGES IN T~ POLYMER. MODEL COMPOUND
STUDY.
_ 26 -
.
A sample of 2.36 g ~10 mmoles) of p-phenoxy-
benzoyl chloride containing 00573 mole % of biphenyl
and 0.573 mole % benzoic acid was polymerized in the
standard manner. One half of the reaction solution
was worked up by precipitation to give a polymer of
inherent viscosity 1.33 and an As value of 10 at
495 nm. This product was compression molded at 400
for 5 min. to give a colorless slab of the same
inherent viscosity 1.33. To the other half of the
polymer ~olution was added 205 g (ca 10-~noles) of
4~bromodiphenyl ether acting as a ~Imodel~ ~or reactive
end gr~ups formed by prior art polymerizations. This
mixture was stirred for 16 hr at room temperature and
then recovered by precipitation into water. The
polymer precipitate was washed with acetone to remove
any excess 4-bromodiphenyl ether followed ~y drying
to give a colorless product of inherent visco~ity
1~33 and an As-value of 540 at 495 nm indicating a
considerable amount of tris-aryl carbonyl structures
forrned. ~his product was compression molded at 400
for 5 min to give a slab of decreased inherent
viscosity ( l-o 2~ 3
~XAMP~ 2
SUPP~ESSIO~ OF GEL FORMATIO~ DURING POLY~ RIZATIO~
2S BY DICAPPING
A sample of 37~9 parts of p-phenoxybenzoyl
chloride containing 0.134 parts (0.50 mole %) of
biphenyl was placed in a cold ~ca 0) pressure
reactor lined with FEP polymer and PqUipped with an
%~3
agitator, heating and cooling coils, a number of
nozzles, pressure and temperature regulating and
controlling devices. ~Ihydrous hydrogen fluoride
was cooIed to -20 in a separate vessel and about 105
parts were slowly added to the monomer with stirring.
The reaction temperature was slowly raised to 20
while maintaining a slow nitrogen purge. Hydrogen
chloride which evolved during this process was
allowed to escape through a condenser (held at -10~
and absorbed in a scrubber. The monomer solution was
then cooled to 0 and boron trifluoride gas was -
a~mitted to give a system pressure of 2.45 kg/cm2 and
a reaction temperature of 14 . These pressure/
temperature conditions were maintained for 4.5 hr.
Then the boron trifluoride supply was discontinued,
and khe reactor and contents were cooled to ~7,
followed by venting of boron trifluoride to the
scrubber until ambient pressure was establîshed. The
resulting polymer solution was transferred to a
larger vessel and diluted with hydrogen fluoride and
13.6 parts of water to give a solids content of 4.5~.
This solution was pressure fed via a polypropylene
cartridge filter (lO~) to a two~fluid spray nozzle for
recovery of solid polymer by spray drying as described
in U~SO patent 3,751,398. During this process, -the
filter cartridge bec~me obstructed by gelatinous
polymer material and had to be replaced four times
- before completing the run. The polymer recovered by
-spray drying was colorless ~nd had an inherent
~ 28 -
~.
3~
viscosity of 1.38. The gelatinous material removed
from the cartridge filter was found to be insoluble ,
in hydrogen fluoride, hydrogen fluoride/boron
trifluoride mixture, or concentrat~d sulEuric acid.
This insoluble material was suspended in hydrogen
fluoride and agitated overnight, followed by
filtration. The filter residue was washed with water
and then dried at 110 /20 mm Hg/16 hr to give a
slightly pink polymer coagulate. Compression molding
at 400 for 5 min gave an incompletely fused, dark
brown slab. The-fused material was not soluble in
concentrated sulfuric acid. Differential scanning
calorimetry indicated a melting point at 365, a
glass transition temperature of 165 and a
recrystallization temperature of 263j the
corr~sponding numbers for the hydrogen fluoride
soluble spray dried polymer are 365, 165 and 210 ,
respectively~ , A sample of 0.0174 g of coagulate from
. the insoluble residue was dissolved in 5 ml of
, dichloroacetic acid at 160 to give a deep red
solution, which'was diluted 1:20 with dichloroacetic
acid and anaIyzed 'by electronic absorption spectroscopy.
A strong band was observed at 495 mm showing an ;
ab~orbance of 0.8. ~Trisphenoxyphenylcarbinol exhibits
~ strong absorption in dichloroacetic acid at 495 ~m
with an extinction coefficient,of 1.1 X 10 . Assuming
that the s~me type of structure Pxists in the polymer
coagulate, c~ulation would,suggest ca 2 mole % of ;
brancheæ/crosslinks.
The above polymer preparation which l~ an example
of the best available prior art technique w~ repeated
- 29
)3
a number of times leadlng invariably to filtex
obstruction of differing severity. When the polymer
preparation was repeated in the presence of 0.50 mole
% of biphenyl and 0.475 mole % of benzoic acid in
accordance with the teachings of the instan~ invention
a polyrner of inherent viscosity 1.35 was obtained and
the batch could be flltered and spray dried without
interruption, in ~act a number of batches could be
filtered through the same cartridge b~fore change
became necessary due to ~ccumulation of foreign,
nonpolymeric material.
EXAMP:I:E 3
BRANCHING DURI~G POL~ER PR:EPARATIO~
Batches of polymer using 37.9 parts of p-phenoxy-
benzoyl chloride were prepared in an FEP lined pressure
- reactor as described in Example 2, i.e., not in
r accordance with the instant invention. In two sets of
experiments no effort was~~nade to remove residual
pol~mer left in the reactor from previous runs (A~
A-2). Then two experiments were run where the reactor
was t~oroughly-cleaned of old polymer be~ore charging
new monomer and anhydrous hydrogen 1uoride (B~1, B-2)o
The polymers were recovered by spray drying and the I
inherent viscosity of powders and compression molded
slabs determined. Slab color (rating: 1 - colorless, I
10 = dark brown~, A5 of the po~der, and extrusibility
of the powder in a % inch Brabender extruder were
evalua~edO The résults obtained are shown belowv
, , .
~ 30
.`~i
~ .
Batch A (495nm) Inheren-t Color E~trud-
s ~iscosity ~o. ~ility
powder. sla~
A 1 250 1.35 1.21 8 No
A-2 314 1.45 1.35 8 No
B-1 14 1.31 1~35 2 Yes
B-2 70 1.40 lo 39 5 Yes
In spi~e of careful removal of old polymer from the
reactor before charging new monomer during a sequence
of ten experiments AS values between 10 and ca
70 analogous to B-1 and B-2 were observed. This did
not have a severe adverse effect on extrusibility but
undesirable color variations in the extrudate were
'notèd. When polymerizations were controlled by
t 15 dicapping with'biphe~yl and benzoic acid in accordance
with the teachings of the 'instant invention instead :~
; of single capping with biphenyl only a~ taught by the
prior a_t Ag values equal to or less than 25 were .
consistently ob~erved.
.
EXAMPLE 4
SHELF LIFE EV~LUTION OF MONO VERSUS DICAPPED poLy~æR
SOLUTIO~S .
- ~ .
Samples o'f -~.32 parts o-f p-phenoxybenzoyl chloride ,
containing 0.50 moIe % of the respective capping agents
lis-ted in the table below were polymerized at room
temperature in 8,parts of anhydrous hydrogen :Eluoride
under a boron trifluoride pressure of 2.1 kg/cm -for :~
4 to 90 hr. The resulting polymer solution~ were
worked.-~ y..-,precipitation into water. Evaluation for
31 - .
. : .
inherent viscosity was conducted in the usual manner
and the results are shown below~
1~IMæ I~HæRENT VISCOSITY
hr Reagënt DiPhenyl- 1,4 diphen Biphenyl/
ether benzophenone Benzoic ~cid
~0.5 mole %
--- -- of each)
41.2* 1.2* 1.5~
9~1.8* 2.3* 1.5+
* These experiments were not in accordance with the
instant invention. I
t These experiments were in accordance with the
instant invention.
This example indicates that double capping in
accordance with the teaching of ~he present invention
provides a consistent vi~c05ity product unaffected
by wide variations in reaction time.
,. . ~ . I
EXAMPLE 5
POLYMERIZATION IN HYDROGEl~ FLUORIDE CONTAINING SULFUR
DIOXIDlE. MONOCAYPING VERSUS DICAPPING
Samples oE p-phenoxybenzoyl chloride containing
0060 mole % of blp~enyl or a mixture of 0.60 mole %
of biphenyl and 0.60 mole % benzoyl chloride were
polymerized at a monomer concentration of 20% in ~
of variable ~ulfur dioxide content for 4 hr at room
temperature and 2ul kg/cm boron trifluoride pressure.
The resulting polymers were recovered in the standard
manner and evaluated for inherent viscosity, the results
are shown below.
- 32
.~ .
,
SULFUR DIOXIDE: INHERENI' VI ',COSITY
CONC.
% Monocapped* Dicappedt
~ 1.3 1.3
1.8 1u4
crosslinked 1.4
Aliquots of the abo~e polymer solutions containing
hydrogen fluo~id~ only as solvent were diluted after
polymerization with sulfur dioxide to give a solids
content of 5%O These solutions were then held for
24 hr under a pressure of 2.1 kgjcm2 boron trifluoride
pressure. Inherent viscosity measurements showed a
substantial increase.for the monocapped polymer while
the dicapped polymer-showed no change.
, . .
SULFUR DI~XIDE . I~IERE~ VISCOSIIY
CONC .
,
. % ~ Monocapped~ Dicapped
.~ ~ .
O 1.3 1.3
2.3 l.3
., .
* ~ot in accordance with the instant invention
t In accordance with the instant invention
.' ' ' '
12XAMPLE 6
POSTPOLYMERIZATIO~ OF DICAPPED VERSUS MONOCAPPED
POLYMER - -
~_ ~
A. A 150 ml:polychlorotrifluoroethylene tube was
. ~ charged with 2.3265 g (10.00 mmoles) of
p-phenoxybenzoyl chloride 0.0077 g ~0.()5 mmoles)
:' . ' .
- 33 -
3~3
1,
of biphenyl, O.057 g (O005 mmoles) o~ benzoic
acid, and a stir bar. To this mixture was slowly
added 10 ml of anhydrous hydrogen fluoride. The
tube was then connected to a polychlorotri-
fluorethylene vacuum lin~ (Toho Kasei CoO Ltd~,
Osaka, Japan) which had been purged with nitrogen.
Boron trifluoride gas was admitted and the
reaction mixtur~ was held at 2.9 kg/cm~ pre~sure
for 4 hr to give a vi~cous orange solution. Exces~ ¦
boron trifluoride wa~ purged from the reaction 1,
system after being cooled to -78C. The polymer
solution was diluted with aqueous hydro~en fluoride
and then poured into rapidly stirred water. The
re~ultant polymar precipitate was iltered and
washed with water, followed by drying at 120/20 mm
- Hg to yield colorles~ fluffy material of inherent
viscosity 1.360
r ~ B. The same proc~duxe was used as in Section A. How-
ever the polymerization time was increa~ed to 8 ~r
and the inherent viscoRity of the product was 1039.
C~ This polymer was prepared following the procedure
of Section A. After 4 hr of polyrnerization, excess
boron trifluoride wa3 purged from the reaction
sy~tem and 0.0146 g (O.04 mmoles~ of 4,4' diphenyl
ether diacid chloride was added to the solution.
Polymerization wa continued for 4 hr~ The in-
hexent vi~co~ity of the product was 1~340 A, ~ C
are in accordance with the in3tant invention.
D. A 1$0 ~l polychlorotrifluoroethylene tube was
_ 34 -
'
charged with 2.3265 g (10.00 mmoles~ of p-phenoxy-
benzoyl chloride, 0oO185 g (O.05 mmoles) of 4,4l_
diphenoxyben~ophenone, ancl a ,stir bar. To this
mixture wa~ slowly added 10 ml of hydrogen fluoride.
The tube was connected to a polychlorotrifluor-
ethylene vacuum line ~hich had been purged with
nitrogen. Boron trifluoride gas was admitted and
the reaction mixture was held at 2.1 kg/cm pressure
for 4 hr to give a vi~cous orange solution. Excess
boron trifluoride was purged from the reaction
system aftar being cooled to -78C. The polymer
solution was diluted with aqueous hydrogen fluoride ¦
and then poured into rapidly stirred water. The
resultant polymer precipitate was f.ilt~red and
wa~hed with water, followecl by drying at 125/20 mm
H~ to yield colorles~ fluffy ma~erial. The in~
herent viscosity of the product w~s 1.30. ~.
E. The same procedure wa~ used as in Section D, h~w~
ever the polymeriæation time wa~ increased to 8 hrO
The inherent vi~cosity ~f the product wa~ 1.31 n
F. Thi~ polymer wa~ prepared following the procedure3
o~ Section D. Af`ter 4 hr of polymerization, excess
boron trifluorid~ was purged from the reaction
~ystem and 0.014~ g (0.04 mmoles) of 4,4'-diphenyl .
ether diacid chloride was added to the ~olution.
~hen polymerization was continued for 4 hr. The
inherent viscosity of ~h~ re~ulting polymer was
4~20. mis ~xperiment wa~ repeated to give a
polymer of inherent visco~ity 4.26. D, E & F
are not in accordance with the instank :invention
- 35 -
~1 . '
.
and indicate the sensitivity of the prior art
product~ to continued polymerization leading to
excessively high molecular w~3ight when contacted
with additional monomer.
EXAMPLE 7 .
MOLECUI~R WE:IGHT CO~TROl: BY DICAPPIl~G WIm BIPHE~E A~D j
BENZOIC ACID ~
A series of polymerization experiments was run
with 10 mmoles of p-phenoxybenzoyl chloride in hydrogen
fluoride (25% solids concentration~ at room temperature
for 4 hr and 2.1 kg/cm of boron trifluoride pre3sure.
Molecular weight was controlled by the addition of bi I -
phenyl and benzoic acid in accordance with the instant
invention over an inherent viscosity range of 1.0 to
1.6~ The results are shown below.
~ ~ .
DICAPPI~G MOLE % INHERENT VISCOSITY
0~00 0~380 1 o58
- 400 o 380 1 ~ 6 2
0~ 600 Oo 570 1 J 23 .
0~ 600 0 ~ 570 1 ~ 27
0~ 700 0 ~ 665 1 ~15
0~700 0~665 1~15
0~800 0~764 1~03
0~800 0~764 1~04
0~900 0~355 0~95
O~ ~00 0 ~ 855 0 ~ g6
EXA~IPLE 8
Using the apparatus and procedures of Example 6, .
a mixture of p-phenoxybenzoyl chloride, p-phenoxybenzo-
phenone (0.5 mol %) and benzoic acid (0.5 mol ~O) were
.
- 3~ - -
~ ,
polymerized to yield a product having e~sentially the
same propertie~ and viscosity as materi.al A, B ~. C of
example 6 when polymerized for like periods of time and .
under similar conditions~
EXAMPLE 9
Using the apparatu~ and procedure~ of example 6 .
a mixture of 4, 4'-diphenoxybenzoph~none (4.95 mmoles~,
terephthaloyl chloride (5.00 mmole~)and p-phenoxybenæo-
phenone (0.1 mmoles) was polymerized to yield a light .
colored fluffy polymer substantially identical.to that ~:
of Example 6A and which ormed a stable ~olution in
hydrogen -fluoride.
EXAMPLE 10 .
Using the apparatu3 and procedures of Example 6
a mixture of ~,4'-diphenoxybenzophenone (5.0 rnmoles) ter- .
ephthaloyl chloride (4.95 mmoles) and benzoic acid (0.1 1
mmole~) was polymerized to yield a material ~ub~tantially ...
identical to that of the last example. :
EX~MPLE 11
Using the apparatus an~ procedureq of Example 6
a mixture of ~-phenoxybenzoyl chlorid~, ~enzoic acid
~0.5 mole %~ and, in three experimentQ, 0.5 mole % of -
p-cyanodip~enylether, p-nitrodiphenylether, and p-phenoxy 1~
diphenyl ~ulfone re~pectively to yield polymeric products 1-
of significant stability in ~ydrogen fluoride solution. .~.
EX~MPLE 12
In a ~imilar manner to that of Example 11 pol~meric ¦:
makerials were prepared from p-phenoxybenzoyl chloride,
biphenyl ~005 mole %) and, in threa experiment~, 0.5 .
~ 37 - .
'
I
~- ~
mole % of p-anisic acid, p-phenyl benzoic acicl, and p-
(4-chlorophenoxy) benzoic acid, saicl materials having
stable viscosities in hydrogen fluoride~
EXAMPLE 13
In a cooled 150 ml Teflon (polytetrafluoroethylene)
flask equipped with a ptfe coated st:irrer was placed
para-phenoxy benzoyl chloride (23.25 parts), biphenyl
(0.077 parts, 0.50 mol % nucleophilic capping agent~,
benzoic acid (0.057 parts, 0~50 mol % electrophilic
capping agent) and a~hydrous hydrogen fluoride (100 parts).
The mixture was stirred at 0C and 2.1 kg/cm2 boron
fluoride presqure applied~ The mi~ture was allowed to
warm to room temperature and stirring continued for 100
hour~. The polymer solution thereby obtained wa~ diluted
to about 5% solids content with hydrogen fluoride contain-
ing 5% w/v water and poured intQ water in a Waring
Blendor. The granular ,product wa washed copiously with I'
water and dried in vacuwm (15 mm Hg3 at 150C for four
hours. m e polymer, obtained in quantitative yiald, had
an inherent viscosity of 1.4 and an As-value of 10 at
495 nm. Thi~ polymer wa~ melt stable and could be readily , '
extruded.
EXAMPLE 14
This is an example using the teaching of the prior
art. The procedure of example ~3 wa~ repeated except
that the benzoic acid electrophilic capping agent was
omitted~ The recovered polymer had an inherent viæcosity
of 1~5 and an A~~value of 400 at 495 mm~ This material
' i
3t3~
w~s essentially inextrusible due to excessive decom-
posi~ion when extrusion was attempted.
EXAMPLE 15
The procedure of example 13 was followed except
that after 4 hours at room temperature the boron fluroide
was ven~ed and the polymer solution ~tirred for another
96 hours. ~he re~ultant polymer had the same good physical 1,
properties including extrusibility and appearanc~ as that
o Example 13.
EXAMPLE 16
This i~ an examplecarried out in accordance with
prior art teachings. The procedure of example 15 wa~
followed except that ~he benzoic acid was omitted. ~he
recovered polymer had an inherent viscosity of 1.45 and
an As-value of 350. Polymer prepared in this way was
found to be inextrusible without extensive deco~positionO
If the polymer is recovered immediately after venting the
boron fluoride (i.e., after 4 ho,urs) a product with an
inherent vi~co~ity of 1.4 and an A~ value of 35 i~
obtained. Polymer recovered rapidly in this way has
satisfactoxy extru~ion performance but this example shows
that the reaction mixtur~ obtaîned by the prior art
proce~es cannot be ~tored for any appreciable length of
time without impairment of the pol~mer processability.
Thi~ ~ensitivity makes the commercial production of such
prior art polymers ver~ difficult to contxol~ In con-
tradistinction, example 15 shows the novel pol~mer~ of
;~ the in~tant invention pos~e~s great ~tability in solution
in acidic media rendering them of great commerciial
uti~it~. I
~ 39
EXAMPLE 16
l~e procedure of example 13 was followed except
that after adding the boron trifluoride the reaction
mixture was stirred at 50C for four hours and then
worked up as in example 13. Polymer produced in this
manner ha~ an inherent viscosity of 'I.40 and an As value
of 20 and can be extruded sa~isfactoxily.
EXAMPLE 17
This is an example carried out in accordance with
prior art teachings~ The procedure of example 16 was
~ollowed except for the omission of benzoic acid. Polymer
produced in this manner has an inherent visco~ity of 1.5
and an A8-value of 415. Thi~ material suffers extensive
cros3linking and discoloration during extrusion. Examples
16 and ~7 show that pol~merizations carried out in
accordance with the instant invention are very little
affected by the temperature of polymerization whereas
polymerizations by prior art processes are extremely
sensitive to reaction temperature. Polymer ~f examples
13-17 comprises recurring units of the structure.
_ _
~ o~ ' _ i
~~_o~ ~
: _ _
- 40 -
'
EXAMPLE 18
POLYMæRIZATION OF p PHENOXYBENZENESULFONYL CHLORIDE.
MONOCAPPING VS. DICAPPING
Sodium p-phenoxybenzene sulfonate .
To a dry 3-neck 5-liter flask, equipped with a
mechanical stirrer and a dropping flmnel, was charged .
400 g (2.35 mole~) o freshly distilled dip~l~nyl ether~
While stirring, 1200 ml of dry dist. methylene chloride
was added slowly. A continuous stream of dry N2 was
passed through the reaction assembly and the flac;k was 1-
cooled to -23 with a dry ice/carbon tetrachloride slush
bath.
From the dropping funnel was added 910wly (ca~ 1 .
hr) with stirring 152 ml ~273 g, 2.35 moles) of dist.
chloro~ulfonic cacid. The reaction mixture was stirred
for 12 hr at -23 and then fox 12 hr at room temperature.
Then 3 liters of ice cold water was slowly added and the
resulting mixture was transferred to a separatory funnel
with the aid of 3 liters of water. The organic phas~
was separated and the aqueou3 phase wa3 extracted with
ether (3 x 80~ ml). The combined organic pha3es were
extracted with water (2 x 1000 ml) then dri~d (.MgSO~) and
freed of solvent (40-50/20 mm) to yiPld 61037 g (0.36
moles) of diphenyl ather. ~he combined a~ueous extracts
w~re briefly heatad to expel organic solv~nts and then
1500 g of solid sodium chloride was added slow:Ly with .
sti.rring~ After cooling to room temperature, the
crystalline precipitate was allowod to stand overnight. .
It was filtexed by centriEugation and washed w.ith 1~/o
- 41 -
~ ' .
3 .
sodium chloride solution. The slightly wet ~ilter cake
was once more recrystallized from water. Work-up of the
mother liquor gave a second crop. ~he filter cakes
were freed of water by centrifuging at ~500 rpm for 1/2
hr, followed by drying at 110Jo.5 mm overnight to aEford
543.4 g (2.0 moles, approximately 10~%, containing ~ome
sodium chloride) of colorless crystal~ine material.
p-Phenoxybenzene sulonyl chloride
A dry 3-neck, 5-liter flask equipped with a
mechanical stirxer, a dropping -funnel, and a nitrogen
sparge was charged with 610 g (2.42 moles) of finely
ground sodium p-phenoxybenzene sulfonate suspended in
1650 ml of dry dimethyl formamude. The reaction flask
was submerged in an ice bath and 195 ml (319 g, 2.68
moles) of distilled thionyl chloride was slowly added
with stirring within one hr~ The ~uspension was stirred
at ro~m temperature for 4 hr and then poured into a cold
0) mixture of ether (1.5 l) and water (l.5 l~ with
viyorous stirring. ~he aquaous p~ase was separated and
extracted with 300 ml of ether. ~he combined organic
extracts were washed with cold watex (300 ml), 10% ~aOH
~olution (2 x 300 ml) and water (2 x 150 ml). The final
wa~h water had a pH o~ 6.5 to 7. The ether solution was
dried (MgS04) and freed of solvent [40-50 (bath)/20 mm~
to give a light yellow oil. A sample o 5 g o finely
ground dry sodium chloride was added and the resulting
suspen~ion was subjected to a short path distillation at
150~160 (bath~j3 x 10 5 mm Hg using a 15 cm Vigraauz
colu~n. The column was jacketed with a haating tapa
kept at approximately 160~ A banana shap~d receiver
- ~2 -
'
3:~
cooled by running water was usedO A colorless distillate
of 534.9 g ~1.99 moles, 82%) was obtalned~ The dis-
tillate crystallized on standing, mp 41 43. Two
recrystallizations from ether/pentane under rigorously
anhydrous conditions gave 480 g (1.78 moles, 74%) of
colorle33 crystals~ mp 43.0-43.5 Zone refining and/or
vacuum sublimation did not raise the mp.
Ir (KBr~ 1181 (s) and 1385 (9) cm 1 (sulfonyl chloride~,
1255 (9) cm 1(ether~, 3080 (w), 1578 (~), 1490 (s) cm 1
(aromatic structure~. Nmr (CDCL3~ ~a 7092 (d, 2H, additional
fine splitting, ~b 7~03 (d, 2H, additional fine splitting),
Jab, 9.1 Hz, 6.9-7.7 (multiplet, 5H) ppm. Anal. Calcd for
C12HgClO3S C, 53.64; H, 3.38, Cl, 13~19, S 11.93. Found:
C, 53.77, 5~.50, 53.59; H, 3.47, 3.40, 3.42, Cl, 13~06,
13.14, 13.26, S, 11.77, 11.86, 11.96. Tlc, A~ter con-
version with pip~ridine to give the sulfonamide [SiO2,
hexane/ether (1/1) a~ ~olvent~: one spot>
; .
- ~ p-Phenoxybenzenesulfonyl chloride samples of two
purity yrade~ were used -for this experiment. One grade
melted at 41-43 and the other at 43-43.5. Samples of
the rPspective monomers (10 mmole) containing either 0.50
mole % biphenyl (mono capped) or 0.50 mole /0 biphenyl and
0.48 mole /0 benzoic acid (dicapped) were polymeriæed in
10 ml of anhydrous hydrogen fluoride at room temperature .
and a BF3 pre~sure o~ 30 psi for 16 hr. The resultant
viscou~ solution~ contained some gelatinous material when
the les~ p~re monbmer was u~ed with biphenyl as capping
: reagent only. The other solutions were all free of gelO
Standard work~up gave c~lorless polymers which were
~valuated for înherent visco~ity before and after
~ompre~ion molding at 400/5 minO The data obtainPd
are shown below. I
- 43 -
MONOCAPPED DICAPPED
Pres~nce Color Presence Color
Monomer Purity ~inh of of ~inh of of
_ _mp powder slab qels Slab powder slab g~ ___ Slab
41-43 1~05 0.50~ Yes Brown 1~00 1.00 No Color-
less
43-43.5 1.00 0~98 No Color- 1.02 1.03 No Color-
less less
The slab dissolved incompletely in conc. H~S04, the
gelatinous material was removed by filtratlon before
viscosity determination.
EXAMPLE 19
A sample of ~.32 parts of p-phenoxybenzoyl chloride containing
0,5 mole % diphenyl ether and 1.0 mole % ben~oic aci.d in accord-
ance with the teachings of the present invention was polymerized
in 10 parts of anhydrous hydrogen fluoride for 4 hr at room tem-
perature under a boron trifluoride pressure of 30 psi. ~he pol~mer
solution was worked up as in example 9 to give a colorless material
which had an inherent viscosity of 1.46 and an As-value of 15
This exp0riment was repeated, but the reaction time was extended
to 9Q hr. The xesultant polymer had an inherent` viscosity of 1051
and an As-value o~ 25. In another set of experimerlts the above
prepaxation of polymer was repeated except that in one experiment
only 0.5 mole % of benzoic acid was used and in the other no
benzoic aci~ was used. In both experiments after four hrs of
reaction the polymer had an inherent viscosity of about 1.45 and
a low As but after 90 hrs of reaction the inherent viscosities
were much higher, the racovered polymers contained gel particles,
were highly colored and had ver~ high As values. These experiments
illustrate the distinct function performed by a molecular weight
~ontrol reagent ~diphenyl ether ? and a capping reagent (benzoic
acid)~
i~ '
44
