Note: Descriptions are shown in the official language in which they were submitted.
~ ~ 7~7,~ ~
DehydrochlorinaCion 0f Vinyl Chloride Resins
The present invention relates to the dehydrochlorination o~
vinylchloride resins such as poly(vinylchloride).
Back~round 0f The Invention
Preparation of graft copolymers of polytvinyl chloride)
using free radical grafting techniques is ine~ficient in that
only low amounts of the grafting monomers becone chemically
attached as grafted polymer to the poly(vinyl chloride) .
backbcne. Compositions resulting from these grafein~ reactions
contain large amounts of un~rafted polymers which are usually
incompatible with poly(vinyl chloride). Consequently, the
materials haNe poor physical, optical and processin~ properties.
The main reason for the grafting inefficiency is the low
reactivity of the poly(vinyl chloride) towards attack by either
,` 15 inieiator or polymer free radicals.
It is known in the literaturel'2'3 that n~ch higher
grafting efficiencies can be obtained by usin~ a poly(vinyl
chloride) backbone that has been partially dehydrochlorinaeed.
Partially dehydrochlorinated poly(vinyl chloride) contains
unsaturated sequences (polyenes) ~hich are quite susceptible to
attack by free radicials.
Various technique~ have been described for prepar~ng
partially dehydrochlorinaeed poly(vinyl chloride)4. Chemical
methods [treatment of poly(vinyl chloride) with bases such as
potassium hydroxide or ammonia] are norm~lly carried out with the
poly(vinyl chloride) dissolved in a solvent such as
tetrahydrofuran in order to ~et uniform dehydro-
chlorinationl'3'5. Uhiform dehydrochlor;nation can also be
achieved by heating a solution of poly(vinyl chloride) in a high
boiling solvent such as ethyl benzoate at eemperatuses above
160C6. Solution eechniques are~very cumbersome, however,
since only dilute solutions ( 5% by weight) can be used and the
resultant dehydrochlorinated poly(vinyl chloride)-must be
recovered from the solvent by evaporation or precipitation~
`~17~ 87`
Base catalyzed dehydrochlorination of solid poly(vinyl chloride) occurs
mainly on the particle surface and there is a strong tendency towards gel
formation. More uniform dehydrochlorination of solid poly~vinyl chloride)
results from a pure thermal process. To obtain uniform dehydrochlorination on
dry, solid resins, the resin particles must be heated and circulated with an
inert gas as in a fluidized bed7. Alternatively, fluids such as ethylene glycol,
paraffin oil or maleic anhydride have been used as media in which the resin
particles can be circulated to provide uniform heat transfer2'8. Poly(vinyl
chloride) has been dehydrochlorinated in dimethylformamide solution containing
lithium chloride9. Poly(vinyl chloride) has been dehydrochlorinated and
sulfonated by treatment in sulfuric acidl. The dehydrochlorinated poly(vinyl
chloride), however~ must be isolated from these fluids prior to free radical
grafting, and the heat transfer fluids have to be purified before being
recirculated. Poly(vinyl chloride) has been treated in aq~leous caustic at 180
to 300C to obtain a high m.w. polymer composed mostly of carbon, hydrogen and
oxygen with traces of nitrogen and chlorine being present 1.
The present invention attempts to a~oid the difficulties alluded to
before and to provide a novel and simple process for the dehydrochlorination
of a vinyl chloride resin and the product of such process.
This invention also provides graft polymers of dehydTochlorinated
vinyl chloride resins.
According to the present invention, there is provided the method
which comprises dehydrochlorinating a vinyl chloride resin selected from the
group consisting of homopolyvinylchloride, a copolymer of vinyl chloride and
vinyl acetate containing up to about 50% by weight of vinyl acetate and a
copolymer of vinyl chloride and vinylidene chloride containing up to about 50%
by weight of vinylidene chloride and mixtures thereof as finely divided
particles suspended in water, by heating said resin in said water at from about
- 2 -
~727~
50 to 150 psi and at a temperature of from about 150 to 1~0C for from about
1 to 2 hours to remove not over about 3% by weight, or from about 1 to 2% by
weight, of chlorine from said resin, said water containing dissolved therein
from about 0.1 to 5 parts by weight per 100 parts by weight of said resin of
a material to prevent agglomeration of said resin during dehydrochlorination
and being selected from the group consisting of a solid watar soluble
electrolyte and a weak base, where said electrolyte is selected from the group
consisting of the lithium, sodium, pot.assium, magnesium, calcium, strontium
and barium bromide, chloride and iodide salts and mixtures of the same, ammonium
chloride and the sodium, potassium, lithium and magnesium acetates and where
said weak base is selected from the group consisting of the lithium, sodium and
potassium carbonates and phosphates and mixtures of the same, and, in said
water, free radical aqueous graft suspension polymerizing on said dehydro-:
chlorinated vinyl chloride resin a monomer containing a polyermizable ethylenical-
ly unsaturated double bond and being selected from the group consisting of amides,
nitriles, acrylates, alkacrylates, dienes and vinyl benzenes and mixtures
thereo:E, said monomer being used in the amount of from about 50 to 200 parts
by weight per 100 parts by weight of said dehydrochlorinated resin.
Thus, this invention offers a method in which a suspension of vinyl
chloride resin can be dehydrochlorinated in the same media (water) in which
the free radical grafting can be subsequently performed. A suspension of the
vinyl chloride resin in water is heated in a closed vessel from about 50 tc
120 psi at from about
- 2a -
~17273~
150 to 180C for fron about 1 to 2 hours. Porous vinylchloride
resins are preferred, although the techniques have been applied
to non-porous resins. During this heating, the vinylchloride
resin becomes partially dehydrochlorinated (not over about 3%
chlorine loss by weight). From about l to 2% by weight chlorine
loss is preferred for use in making the graft copolyners
described herein. With higher levels of chlorine loss in this
process, there is a tendency for gel ~ormation and increased
color in the subsequent graft copolymers. With chlorine losses
above 5% by weight, the resultant dehydrochlorinated
vinylchloride resin itself tends to become crosslinked.
The graft copolymers are produced by reacting the dehydro-
chlorinatecl vinylchloride resin with monomers and free radical
initiato¢s in an aqueous suspension process. The grafted product
is in the form of free-flawing particles which can be recovered
by filtration or centrifugation. This method also offers the
possibility of using the aqueous suspension for dehydro-
chlorination and grafting obtained originally by polymerizing the
vinylchloride resin by a suspension polymerization process. The
resultant graft copolymer can thus be produced directly in the
same aqueous media and vessel in which the vinyl chloride is
polymerized provided there are no inhibitors, short stops or
catalysts residues present which might interfere with the
subsequent graft polymerization or copolymerization. This will
save the steps required in isolating the vinylchloride resin. In
addition, ~mlike the techniques described in the previous
literature, no solvents or other organic media are required for
the dehydrochlorination.
During the dehydrochlorination in water there is a tendency
for the dehydrochlorinated vinylchloride resin to agglomerate,
possibly due to the development of electrostatic charges. It has
been found that this agglomeration preferably can be avoided by
carrying out the dehydrochlcrination in a dilute electrolyte
(e.g. sodium chloride, sodium iodide) solution. Free-flowing
~7~71~
partîcles of partially dehydrochlorinated vinylchloride resin,
thus, can be obtained. Alternatively, it is possible to
introduce weak bases (e.g. sodium carbonate, trisodium phosphate)
to capture the hydrogen chloride evolved during dehydro-
chlorinatic~. Also, the acid in the water may be neutralizedwith NaOH or other alkaline solutions.
I~hen monomers such as acrylates are grafted to the
partially dehydrochlorinated poly(vinyl chloride), there is a
significant increase in the grafting efficiency (% acrylate
grafted to the vinylchloride resin) compared to compositions
obtained from unmodified vinylchloride resins. The high level of
grafting results in increased compatibili~y and significant
improvement in the physical, optical and processing properties of
the resin. If monomers with a low glass transition temperature
(such as acrylates) are grafted to the partially
dehydrochlorinated vinylchloride resin, internally plasticized
vinylchloride resin compositions result. These compositions are
useful in makin~ films and coated fabrics and can be calendered,
molded or e~truded into various flexible products such as in
covers for ar~ rests, seats, chairs and so forth.
Discussion Of Details And Preferred Embodiments
The vinylchloride polymer or resin to be dehydrochlorinated
is homopolyvinylchloride, vinylchloricle-vinyl acetate copolymer
containing up to about 50/O by weight of vinyl acetate, and
vinylchloride-vinylidene chloride copolymer containing up to
about 50% by weight of vinylidene chloride and mixtures.of the
sameO m ese polymers are made by the suspension polymerization
process. Suspension polymerization is well known as shown by
Schildknecht, "Vinyl and Related Polymers," 1952, John Wiley &
Sons, lnc., New York. See, also, '~odern Plastics Ehcyclopedia,"
October, 1980, Volume 57, Number 10A, McGraw-Hill Co. Inc., New
York, pages 104, 10~ and 110. These suspension polyners are
obtained as finely divided particles or solids. The preferred
vinylchloride resin to use is poly(vinylchloride).
1 ~L727~'~
Sufficient water is used during dehydrochlorination to suspend the
particles of the vinyl chloride resin. Generally, there may be used a suspension
of from about 15 to 50% by weight solids of the vinyl chloride resin in water,
preferably about 25% solids of the vinyl chloride resin in water.
The water soluble solid electrolyte ~a substance which dissociates
into two or more ions) or salt used to prevent agglomeration can be a water
soluble halide salt of an alkali metal or alkaline earth metal such as a lithium,
sodium, potassium, magnesium, calcium, strontium or barium bromide, chloride or
iodide salt or mixture thereof. Examples of such salts are lithium chloride,
lithium iodide, sodium chloride, sodium bromide, sodium iodide, potassium
bromide, magnesium chloride, calcium bromide, calcium iodide, barium chloride,
barium iodide, strontium chloride and strontium bromide. Sodium chloride is
the preferred salt to use.
Still other water soluble electrolytes can be used such as ammonium
chloride, sodium acetate, potassium acetate, lithium acetate, magnesium acetate
and so forth.
The weak base ~a base that does not ionize greatly) used to prevent
agglomeration can be an alkali metal carbonate or phosphate like sodium carbon-
ate, trisodium phosphate, lithium carbonate, lithium phosphate, potassium
carbonate, or potassium phosphate or other water soluble solid weak base or
mixture thereof.
On a dry weight basis the electrolyte or weak base is used in a very
minor amount of weight as compared to the vinyl chloride resin and sufficient
to prevent agglomeration during dehydrochlorination of the vinyl chloride resin.
Preferably, the electrolyte or weak base is used in an amount of from about
0.1 to 5.0 parts by weight per 100 parts by weight of the vinyl chloride resin.
After dehydrochlorination of the vinyl chloride resin in water may be
filtered or centrifuged to remove the water, washed and then resuspended in
t- ~
I ;J
.~ .~
;l172~
water to permit graft polymerization. Since the water ln which the vinyl
chloride resin is mixed usually
- 5a -
.~72~7
contains not more than about 0.10 mole of acid, it may be used as
the graft polymerization or copolymerization medium provided the
monomers used are not affected adversely.
The technique of polymerizing or copolymerizing one or more
monomers in the presence of a polymer or a substrate, "~raftin~
~echnique," is kncwn and is frequently called graft
polymerization or graft copolymerization. In this connecticn,
please see "Proceedings 0~ The Third Rubber Technology Gongress,"
1954, W~ Heffer & Sons, Ltd., Cambridge, pages 185-195;
"Copolymerization," High Polymers, Vol. XVIII, Ham, Interscience
Publishers a division of John Wiley & Sons, New York, 1964;
"Block and Graft Polymers," Burlant and Hoffm~n, Reinhold
Publishing Corporation, New York, 1960; "Block and Graft
Copolymers," Ceresa, Butterworth & Co. (Publishers) Ltd., London,
1962; Ceresa, "Block and Graft Copolymerization," Vol. 1 (1973)
and Vol. 2 (1976), John Wiley & Sons, Ltd., ~ew York; and '~Graft
Copolymers," Polymer Reviews, Vol. 16, Battaerd and Tregear,
Interscience Publishers, a division of John Wiley & Sons, New
York, lg67. See, also, U.S. Patents ~s. 3,180,908 and
3,519,702. The graft copolymer may c~ltain all graft copolymer
but also may be a mixture of homopolyners, copolymers as well as
the graf~ itself, depending on the rate of polymerization of the
monomers under the polymerization conditions and so forth.
Examples of monomers which may be graft polymerized or
copolymerized with the dehydrochlorinated vinylchloride resin are
those monamers containing polymerizable ethylenically unsaturated
double bonds such as the amides like acrylamid~, methacrylamide
and N-hydroxymethyl acrylamide; the nitriles like acrylonitrile
and methacrylonitrile; the acrylates and aLkacrylates like methyl
acrylate, ethyl acrylate, butyl acrylate, ethyl hexyl acrylate,
octyl acrylate, hydroxy ethyl acrylate, hydroxy propyl acrylate,
methyl methacrylate, ethyl methacrylate, butyl methacrylate,
methyl ethacrylate, ethyl ethacrylate, butyl ethacrylate and
octyl ethacrylate; the dienes such as butadiene-1,3, chloroprene~
2,3-dimethyl butadiene-1,3, piperylene and isoprene, and the
~7278~
vinyl benzenes like styrene, alpha m~thyl styrene, p-tertiary
butyl styrene, methyl vinyl toluene and para vinyl toluene and
the like and mixtures of the same.
When graft copolymerizin~ a hard monomer like styrene, it
is desired to include with the styrene a sufficient amount of a
soft monomer like butyl acrylate or butadiene to act as a
plasticizer. Also, comonomers like acrylonitrile mqy improve
homogeniety and compatibility in the resulting resin. Even
though both acrylonitrile and methacrylonitrile can be used in
these graft copolymers, it has been found thae the latter has
l~ss tendency to yellow. The parts by weight ratio of the soft
monomer to the hard monomer may be from about 2:1 to 20:1.
It is particularly desirable to use mixtures of nitriles
and acrylates which can form polyacrylates having a low Tg such
as on the one hand acrylonitrile or methacrylonitrile and on the
other hand an acrylate or methacrylate monomer which could form
an acrylate polymer having a Tg (glass transition temperature) of
not above about -20C. Examples of such acrylate monomers are
ethyl acrylate, n-propyl acrylate, n-butyl acrylatel hexyl
acrylate, octyl acrylate, 2-ethyl hexyl acrylate, decyl acrylate,
methoxy ethyl acrylate, ethoxy ethyl acrylate, methoxy propyl
acrylate and ethoxy propyl acrylate and the like. These
monomers, thus, have the ~eneral formula CH2=CH-o~OR where R is
an alkyl group of 2 to 10 carbon atoms or a -R'oR" group where R~
is an alkylene group of 2 to 3 carbon atom~ and R" is a~ alkyl
group of 1 to 2 ca~bon atoms. It will be noted that poly(n-butyl
acryla~e) has a Tg of -55C. and poly(2-ethyl hexyl acrylate) has
a Tg of -77C. Also, there may be used as the a ylate monomer,
mononers having the formula ~ C-C(C ~)COOR " ' where R " ' is
an alkyl group of 8 to 18 carbon atoms such as n-octyl
methacrylate, n-dodecyl methacrylate, hexadecyl methacrylate and
n-octadecyl ~ethacrylate and the like. Poly~nqoctyl
methacrylate) has a Tg of -20C. and poly~n-octadecyl
methacrylate) has a Tg of -100C. Mixtures of these acrylate
monomers may be used. However, the higher molecular weight
acrylate and methacrylate monomers are less compatible (phase
~7~7~
-- 8 --
separation~ with polyvinyl chlcride. Thus, the higher molecular
weight acrylate and methacrylate monomers should be used in
mixtures, in am~unts up to 25% by wei~ht of the mixture, with a
lower molecular weight acrylate like ethyl, propyl and/or butyl
acrylate. Of these acrylate mono~ers it is preferred to use
n-butyl acrylate.
Overall in the graft polymerization process there can be
used from about 50 to 200 parts by weight of the grafting monomer
or monomer mixture per 100 parts by weight of the
dehydrochlorinated vinylchloride resin.
Graft polynerization should be conducted in a closed
reactor, such as a pressure reactor, fitted with a stirrer or
other agitating means, heating and cooling means, with means to
flush with or pump in an inert gas such as nitrogen, helium,
argon, neon and the like in order to polymerize preferably under
controlled, inert or non-reactive conditions, with means to
charge the resin (if previously separated), monomers, water,
initiators and so ~orth, venting means, and with means to recover
the graft polymer and so forth. The reactor should be cleaned or
Elushed out between polymerization ruls to remove traces of
initiators, modifier, colloids, residues and the like which might
interfere with subsequent polymerizatiLons. There should be
sufficient agitation or stirring of the polymerization media to
ensure thorough mixing, diffusion, ca~tact and so forth. All of
the polynerizaticn ingredients may be charged to the reactor at
the sa~e time, intermittently, increm~ntally or continuously.
Also, the ingredients may be added separately or in a nuxture.
Temperatures used during ~raft polymerization should be
sufficient to effect polymerization by activation of the
initiator and double bonds of the mKnomers. They should not be
too high to cause a runraway reaction and not too low to retard
polymerization. In general, the temperature m~y be from about 2
to ~0C. I~ even lower temperatures are used, it may be
desirable to add an-inert anti-freeze ~aterial to the
'' ""' ' .:
;
~ ~2~
g
polymerization media. Water is used in an amount sufficient to
obtain the desired degree of suspension or dispersion, cooling,
mixing, solids content and so forth.
Graft polymerization of the monomers is efEected by
free-radical initiators Gfree-radical formers or free-radical
fornun~ systems, catalysts) such as ammonium, potassium~or sodium
persulfate, ~ 2 and the like in an amount sufficient for
polymerization of the monamers. Other free-radical initiators
can b~ used which decompose or become active at the temperature
used during polymerization. Examples of some other free-radical
initiators are cumene hydroperoxide, dibenzoyl peroxide, diacetyl
peroxide, didecanoyl peroxide, di-t-butyl peroxide, dilauroyl
peroxide (preferred), bis (plmethoxy benzoyl) peroxide, t-butyl
peroxy pivalate, dicumyl peroxide, isopropyl percarbonate,
di-sec-butyl peroxydicarbonate, azobisdimethyl-valeronitrile,
2,2'-azobisisobutyTonitrile, 2,2'-azobis-2-methylbutyronitrile
and 2,2'-azobis Gmethylisobutyrate) and the like and mixtures of
the same. 0nly minor am3unts of initiators are necessary to
effect polymerization.
Protective colloids having little surface activity are
desirably used in the graft suspension polymerization process to
provide finely divided particles suspended in the aqueous
medium. Examples of useful protective colloids are copolymers of
from 30 to 50% vinyl acetate, balance 1-vinyl-2-pyrrolidone.
Other polymers can be used as a colloid such as those obtained by
copolymerizing a pyrrolidone, such as l-vinyl-3-pyrrolidone, or
vinyl piperidone, with a copolymerizable mKnomer`like vinyl
acetate, acrylic acid, methacrylic acid, butyl acrylate, ethyl
acrylate, methyl acrylate, ethyl vinyl ketone, allyl acetone,
methyl (5-hexene-2-one) vinyl ether, vinyl isobutyl ether, allyl
alcohol, 3-buten-1-ol, and the like and mixtures thereof. Still
other protective colloids may be used, for example, gelatin,
polyacrylamide, hydroxy ethyl cellulose, hydroxy propyl methyl
cellulose (preferred), carboxy methyl cellulose,~methyl
cellulose, gun arabic, gum tra~acanth, lcw molecular weight
polyvinyl alcohols etc. These protective colloids are used in
., ~
~ 1727~
- 10 -
amounts of frorn about 0.01 to 4.0% by weight, and preferably from
about 0.1 to 2% by weight, based on the weight of the graft
polymer obtained.
Other materials which may be used during the graft
polymerization are chelating or sequestering agents, chain
transfer agents or modifiers such as tertiary alkyl merc ptans to
prevent or reduce gel, stabilizers, antioxidants and shortstops
~to stop the polymerization at the desired conversion and prevent
further polymerization during stripping, work-up and so forth).
Swelling agents for the dehydrochlorinated resin, also, may be
used to facilitate ~he graft polymerization or copolymerization
processO
The following examples will serve to illustra~e the present
invention with more partlcularity to those skilled in the art.
In these examples the parts are parts by weight unless otherwise
noted.
Example 1
PVC I (3,000 gr~ms) and ethylene ~lycol (12 liters) were
charged to a 5-gallon stainless steel reactor. The reactor was
equipped with a stirrer, electrical strip heaters and a bottorn
take-off valve. The reactor with its contents were heated to
160C over a period of 50 minutes. The wall temperature of the
reactor was maintained at 165C (which kept the ethylene
glycol/PVC I slurry at 160CC) for 2 hours. Ihe reactor and its
contents were cooled to ambient temperatule and the ethylene
glycol/dehydrochlorinated PVC I slurry was discharged through the
bottom valve. Ihe dehydrochlorinated PVC I was recovered by
filtration and was washed with water and dried. The dried resin
consisted of orange-colored particles and had 55.78% chlorine
(original PVC I has 56.73% chlorine). The resin was soluble in
tetrahydrofuran and had a series of absorbances in the visible
spectrum from 250-600 nm, characteristic of polyene sequences of
different len~ths ~approximately C2 ~o C12).
Exanpl~ 2
m e method described in Exanple 1 was repeated exactly,
except that the ethylene glycol was replaced with water (14
.
7~7~
11 -
liters~. Ihe dehydrochlorinated P~C I could not be discharged
through the bottom valve but was caked in the upper level of the
reactor. This cake was removed, broken up into fine particles,
washed with water and dried. The resultant orange-colored resin
had 55~7~/O chlorine and was soluble in tetrahydrofuran. A series
of abscrbances was found in the visible spectrum from 250-600 nm,
characteristic of polyene sequences of different lengths.
Example 3
The method described in Example 2 was repeated exactly,
except that 75 grams of sodium chloride were added to the
water/PVC I mixture. The resultant dehydrochlorinated PVC I
flcwed freely through the bottom valve of the reactor. Ihe res;n
was recovered by filtration, ~ashed with water and dried. The
resultant dehydrochlorinated PVC I was orange-colored, soluble in
tetrahydrofuran and had 56.24% chlorine. The visible spectrum
showed a series of absorbances from 250-600 nm, characteristic of
polyene sequences of various lengths.
Exame~e 4
The method of Example 3 was repeated exactly, except that
the temperature of the waterlPVC I slurry was kept at 150C. The
resultant dehydrochlorinated PVC I discharged easily from the
bottom valve of the reactor. The resin was orange-colored,
soluble in tetrahydrofuran and had 56.46% chlorine.
Example 5
Ihe method of Example 4 was repeated exactly, excep~ that
the temperature of the waterlPVC I slurry was kept at 140C. The
dehydrochlorinated PVC I resin that was recovered consisted of
small orange particles which were soluble in tetrahydrofuran and
had 56.15% chlorine.
Exa~
The method of Example 4 was repeated exactly, except that
the sodium chloride was replaced with 75 grams of sodium iodide.
The dehydrochlorinated P~C I that resulted discharged easily from
the bottom valve of the reactor. It was orange-colored, soluble
in tetrahydrofuran and had 55.63% chlorine.
1~727~'7
- 12 -
Example 7
The method of Example 2 was repeated exactly, except that
the reactor contents were heated at 155C and 10.5 grams of
sodium carbonate were added to the slurry. The resultant
dehydrochlorinated PVC I discharged easily from the bo~tom valve
of the reactor. It was dark yellow-colored, soluble in
tetrahydrofuran and had 55.52% chlorine.
Example 8
The method of Example 3 was repeated exactly, except that
the poly(vinyl chloride) used was PVC II instead of PVC I. The
dehydrochlorinated PVC II discharged easily from the bottom valve
of the reactor. It was orange-colQred, soluble in
tetrahydrofuran and had 56~4~/o chlorine.
Example 9
The method of Example 3 was repeated exactly, except that
PVC III was used instead of PVC I. The dehydrochlorinated PVC III
discharged easily from the reactor. It was orange-colored,
soluble in tetrahydrofuran and had 56.()9% chlorine.
Example 10
Example 3 was repeated exactly, except that PVC IV was used
instead of PVC I. m e dehydrochlorinal:ed PVC IV discharged
easily from the reactor. It was pale yellow, soluble in
tetrahydrofuran and had 56.61% chlorine.
Example 11
25~ A mixture of n-butyl~acrylate (S0 grams), methacrylonitrile
(5.25 grams) and "Alperox'~rF (2 grans) (dilauroyl peroxide, 98C/
Pe~nwalt, Lucidol Chem. Div.) was prepared. ~his mixture was
added to a quart polymerization bottle ~hich contained PVC I (50
grams), water ~400 grams3 and '~ethocel J 75 HS (0.25 gram)
ohydroxy propylmethylcellulose, Dow Chemical Co.). The bottle
was capped and placed in a 6~C polynerization bath. The bottle
and its contents were rotated in the bath at 60C for 18 hours.
The bottle was r~moved and its contents were poured onto a
filter. The filtered product was washed with water and dried. A
~ Tr~e ~ k
1 ~ 727~
- 13 -
99% yield of product was obtained which consisted of small white
particles. Five grams of this product were placed in a Soxhlet
extraction apparatus and extracted for 36 hours with
cyclohexane. The cyclohexane dissolved 1.8 grams of ungrafted,
rubbery product which was shown by infrared spectroscopy to
consist of a copolymer of butyl acrylate and methacrylonitrile.
On this basis, a grafting efficiency (% of the acrylate reacted
that became grafted to the PVC I) of 31% was calculated.
Example 12
The method of Example ll was repeated exactly, except that
the reaction product of Example l was used instead of PVC I.
During the grafting reaction, the orange-colored
dehydrochlorinated poly(vinyl chloride) was transformed into a
product which consisted of small while particles. The grafting
efficiency, as determined by cyclohexane extraction, was 63%.
Examp~
The method of Example 11 was repeated exactly, except that
the reaction product of Example 3 was used. A product consisting
of small while particles was obtained. The grafting efficiency
was determined to be 7~/O~
Example 14
Using the same generalized procedure described in Example
11, graft copolymers were made from all of the dehydroch~orinated
poly(vinyl chloride) samples obtained in Examples l-10. The
25 ~ grafted products were mixed wi,th typical poly(vinyl chloride)
stabilizers using a Brabender~Plasti-Corder at 150C.
C~mpression- lded tensile sheets were prepared at 150C from the
various compositions. The physical properties of each
composition are listed in the following table.
~T~ a,rk
~727~
- 14 -
'rable
Poly(vinyl
chloride) Used 100% Tensile Graves
for Graftin~ Mbdulus ~ Elon&ation Tear Shore "A"
MPa MPa % kN/m
PVC I
(E~ample 11) 5.79 6.69 240 35.7 90
Example 1 7.52 10.5 235 49.2 91
EKample 2 7.26 10.0 235 48.6 8g
Exanple 3 6.93 9.9 235 48.6 90
Example 4 8.53 11.3 260 51.1 96
Example 5 7.65 9.5 235 44.5 94
EXample 6 8.23 11.5 255 52.5 96
Exanple 7 7.39 10.1 230 45.2 92
Example 8 7.16 9.9 300 53.0 94
E~ample 9 8.97 11.9 230 52.5 96
F~mple 10 8.16 8.63 140 43.0 95
Notes:
1. U.S. Patent ND. 2,908,662, W. Rees.
20 2. U.S. Patent Nb. 3,576,914, J. Dbnat.
3. 0stensson and Flodin, JO Macramol. Sci.-Chem., A12(2),
249-260 (1978).
4. D. Braun, Pure and Applied Chemistry, Vol. 26, #2, 173
(1971).
25 5. A. Wirsen and P. Flodin, J. Appl. Poly. Sci. 22, 3039
(1978).
6. I. K. Varma and K. K. Sharma, Oie Angewandte
Makromolekulare Chemie 78, 181 (1979).
7. Netherlands Patent Specification 7214020, Dow Chemical Cn.
30 8, U.S. Patent Nb. 3,896,091, H. J. Fabris, H. Ublzmann and
W. J. van Essen.
9. J. P. Roth, P. Rempp and J. 8arrod, Jour. o~ Polymer
Science, Part C, Nb. 4, L~i7 (1963).
10. Z. Wolkober, Jour. of Poly,ner Science, Vol. 58, 1311
(1962).
11. U.S. Patent Nb. 3,826,789~ C. Yokokawa.
` 1;~72~7
- 15 -
PVC I Homopolyvinylchloride, inherent viscosity of 0077,
ASIM-D1755, porous.
PVC II Homopolyvinylchloride, inherent viscosity of 0.$7,
ASTM-D1755, non-porous.
PVC III Homopolyvinylchloride, inherent viscosity of l.Q3,
ASIM-D175S, porous.
PVC IV HomDpolyvinylchloride, inherent viscosity of 0.99,
ASTM-D1755, non-porous.
PVC I, II, III and IV were all finely divided, free-radical,
aqueous suspension polymerized vinylchloride polymers.
