There are disclosed polymerizable thioester synergists which have utility in enhancing the antioxidative activity of phenolic and amine stabilizers. The invention is also concerned with the thioesters themselves, their use in oxidizable organics, their combination with polymerizable and/or conventional antioxidants, and with polymers which contain these thioesters as physical admixtures or segmeric units of the polymer.

TECHNICAL FIELD 
This invention is concerned with polymerizable thioester synergists and to 
antioxidant systems which employ thioester synergists. More particularly, 
this invention relates to organic compositions stabilized against 
oxidative degradation by a stabilizing system comprising a novel thioester 
compound and phenolic and/or amine antioxidant(s). Vulcanized and 
unvulcanized polymers containing these novel thioesters as segmeric units 
have demonstrated a synergistic effect with phenolic and amine 
antioxidants. 
BACKGROUND ART 
It is well known that organic materials such as plastics, rubbers, 
lubricating oils, etc. are prone to oxidation and deterioration in the 
presence of oxygen. Oxidation of organic materials causes the loss of 
those intrinsic properties characteristic of the organic material. With a 
view to preventing deterioration, a variety of antioxidants and 
antiozonants have been developed; however, these stabilizers fail to 
prevent completely the deterioration of the desired properties of the 
materials to which they are added. Thus, those skilled in the art are 
constantly searching for new and more effective stabilizing systems which 
are useful for the protection of polymers and other organic materials. 
Synergists have been known in the art for some time. See for example U.S. 
Pat. No. 3,492,336 which discloses a novel tetra-alkyl thioethyl 
thiodisuccinate compound for use with phenolic type antioxidants in the 
stabilization of polyolefins. 
U.S. Pat. No. 4,254,020 discloses compounds such as 
2,12-dihydroxy-4,10-dithia-7-oxatridecamethylene 
bis[3-(dodecylthio)propionate] as a synergist with phenolic antioxidants. 
In U.S. Pat. No. 3,398,116 a thiocarboxylic acid thioether ester is used in 
combination with a limited group of phenolic antioxidants to stabilize 
poly-alphaolefins against oxidative degradation. 
U.S. Pat. No. 3,758,549 discloses polyalkanol esters of alkylthio-alkanoic 
acids as synergists with phenolic antioxidants and U.S. Pat. Nos. 
3,666,716 and 3,505,225 disclose derivatives of diphenylamine and 
phenylnaphthylamines as antioxidants with dialkyl 3,3'-thiodipropionates 
as a synergist. U.S. Pat. No. 3,450,671 discloses polyolefin compositions 
stabilized with dialkyl 3,3'-thiodipropionate and a polyphenol. 
An article by R. Chandra, Polymer, Vol. 24, February 1983 discloses 
styrene-butadiene copolymers stabilized with a synergist mixture of the 
antioxidant 3,5-di-t-butyl-4-hydroxybenzylmercaptan in combination with 
1,1,5-triphenyl-2-s-(3',5'-di-t-butyl-4'-hydroxy)benzyl-iso-4-thiobiuret 
bound to the polymer as a synergist. 
The art of using a combination of antioxidants has been utilized by the 
industry, and such stabilizing systems are often highly effective. 
Conventionally used synergists are normally added to the material to be 
stabilized during a mixing operation. It was thought that for a compound 
to exhibit synergistic properties with an antioxidant or antiozonant it 
would require a certain amount of mobility within and about the polymer 
structure. The present invention has unexpectedly discovered that 
synergists can be attached or "bound" to a polymer (a segmeric unit of the 
polymer) and still exhibit synergistic properties with a phenolic or an 
amine stabilizer. Further, it has been discovered that bound synergists 
demonstrate activity with what is now known in the art as bound 
antioxidants. This is highly unexpected and contrary to numerous and 
various teachings in the art. It has been discovered that the particular 
compounds of this invention can be co-polymerized with other monomers to 
form a polymer that has chemically attached to it, via a covalent bond, a 
moiety which can synergistically enhance the antidegradative properties of 
phenolic and amine antioxidants. 
It has also been discovered that the compounds of this invention can be 
grafted onto the polymeric backbone using a technique similar to that 
described in U.S. Pat. No. 4,155,955 which is herein incorporated by 
reference. 
The majority of the synergistic stabilizers to date have been used in 
conjunction with phenolic antioxidants since use with amine antioxidants 
has not demonstrated synergistic properties. It was felt that synergism 
was simply overpowered by the excellent stabilizing properties of 
compounds such a N,N'-p-phenylenediamine. In this regard, it is surprising 
that the compounds of the instant invention demonstrate synergistic 
activity with amine type antioxidants. As a result of these discoveries, 
it has been found that the combined use of the compounds of this invention 
and an antioxidant brings about an unexpectedly powerful antioxidative 
effect. None of the cited patents or other literature in the art has 
disclosed or even suggests the synergist compounds disclosed in this 
invention. 
DISCLOSURE OF THE INVENTION 
The present invention relates to a stable organic composition which 
comprises an oxidizable diene containing polymer, a phenolic and/or amine 
antioxidant and a compound selected from formulae I-XII: 
##STR1## 
wherein 
R is selected from hydrogen, methyl or phenyl radicals; 
R.sup.1 is selected from hydrogen, methyl or ethyl radicals; 
R.sup.2 is selected from hydrogen or methyl radicals; 
R.sup.3 is selected from hydrogen, alkyl radicals of 1 to carbon atoms, 
phenyl and substituted phenyl radicals; 
R.sup.4 is an alkyl radical of 1 to 3 carbon atoms; 
Q may be the same or different divalent radical selected from --O-- or 
--NH--; 
.beta. is 0 or a whole number from 1 to 20; 
n is a whole number from 2 to 20; 
m is 0 or 1 or 2; 
x is a whole number from 1 to 20; 
.alpha. is a monovalent radical selected from alkyl radicals of 1 to 30 
carbon atoms, the radical 
##STR2## 
or the radical 
##STR3## 
wherein R.sup.2, R.sup.3 and .beta. are defined as above and R.sup.5 is 
selected from hydrogen, hydroxyl and alkyl radicals of 1 to 10 carbon 
atoms. 
The present invention also relates to the compounds expressed by formulae 
I-XII, to synthetic polymers prepared from polymerizable comonomers and a 
compound selected from formulae I-XII and to polymers that have grafted 
onto the polymeric backbone a compound of formulae I-XII. The present 
invention also relates to vulcanized polymers containing compounds 
expressed in formulae I-XII. 
These compounds exhibit their novel properties when combined with a variety 
of stabilizers known as phenolics and amines, many of which are 
commercially available and some of which are the subject of patents. 
Generally speaking, the thioesters of the instant invention contain a 
polymerizable moiety and a synergistic moiety. It has been determined and 
will be demonstrated infra that the relationship of the particular atoms 
is critical to the viable functioning of the synergist.

DETAILED DESCRIPTION OF THE INVENTION 
Typical of the phenolic antioxidants with stabilizing properties that are 
improved by the addition of compounds of the present invention are 
phenolic compounds having the general formula: 
##STR4## 
wherein R is a tertiary alkyl radical having 4 to 8 carbon atoms, a 
cycloalkyl radical having 5 to 12 carbon atoms, or an aralkyl radical 
having 7 to 12 carbon atoms, and wherein R.sup.1 and R.sup.2 are alkyl 
radicals having 1 to 12 carbon atoms, cycloalkyl radicals having 5 to 12 
carbon atoms, or aralkyl radicals having 7 to 12 carbon atoms; or 
polyphenolics of the formula: 
##STR5## 
wherein R is an alkylidine radical having 1 to 4 carbon atoms, the group 
--O--, or the group --S--, and wherein R.sup.1 and R.sup.2 are alkyl 
radicals having 1 to 12 carbon atoms, cycloalkyl radicals having 5 to 12 
carbon atoms, or aralkyl radicals having 7 to 12 carbon atoms. Preferably 
at lease one of R.sup.1 and R.sup.2 is a tertiary alkyl radical having 4 
to 8 carbon atoms and is in a position ortho to the hydroxyl group. 
Other antioxidants such as: 
##STR6## 
are useful with the synergists of this invention wherein n is an integer 
from 1 to 4 and R is an alkyl radical having 8 to 20 carbon atoms, an 
alkylene radical having 2 to 6 carbon atoms, a thiodialkylene radical 
wherein each alkylene radical has 2 to 6 carbon atoms, a trivalent radical 
derived from a straight or branched chain hydrocarbon having 3 to 8 carbon 
atoms, or a tetravalent radical derived from a straight or branched chain 
hydrocarbon having 4 to 8 carbon atoms. 
Specific phenolic antioxidants applicable in the present invention include: 
2,6-di-tert-butyl-4-methylphenol 
2,4,6-tri-tert-butylphenol 
2,2'-methylene-bis-(4-methyl-6-tert-butylphenol) 
2,2'-thio-bis-(4-methyl-6-tert-butylphenol) 
4,4'-thio-bis-(3-methyl-6-tert-butylphenol) 
4,4'-butylidene-bis-(6-tert-butyl-3-metylphenol) 
Styrenated phenol 
Butylated Octylated Phenol 
Butylated-methylstyrenated phenol 
Styrenated butylated m, p-cresol 
4,4'-methylenebis (2,6-di-tert-butylphenol) 
2,2'-methylenebis[4-methyl-6-(1-methylcyclohexyl)-phenol] 
2,5-diamylhydroquinone 
2,6-ditert-butyl-4-butylthiophenol 
Butylated reaction product of p-cresol and dicyclopentadiene 
Tetrakis[methylene 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]methane 
1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene 
Thiodiethylene bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] 
Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate 
2,6-bis(1-phenylethyl)-4-(1-phenylethylthio) phenol 
Typical of the amine antioxidants with stabilizing properties that are 
improved by the addition of compounds of the present invention are the 
naphthylamines, diphenylamine derivatives, quinolines, 
para-phenylenediamines and the blended amines. A diphenylamine derivative 
especially useful is the alkylated diphenylamine known as Wingstay.TM. 29 
(Trademark of The Goodyear Tire & Rubber Company). The quinoline 
antidegradants are of two types--the polymerized and the non-polymerized 
dihydroquinolines and the substituted dihydroquinolines. Numerous 
para-phenylenediamines have been produced and used as antiozonants. 
Representative examples are Wingstay.TM. 300 and 100, Flexzone.TM. 3C and 
6H (products of Uniroyal, Inc.). 
Another class of antioxidant that is useful with the compounds of the 
instant invention are the polymer bound antidegradants. Most recently, 
numerous investigators have studied the stabilizing properties of polymers 
that have as one of their segmeric units an antioxidant functionality. A 
more complete discussion of suitable polymeric antidegradants useful with 
the compounds of the present invention can be found in U.S. Pat. Nos. 
3,984,372, 3,962,187, 3,953,402, 3,953,411, 4,097,464, 4,152,319 and 
3,658,769. The compounds of the present invention have as one of their 
characteristic properties the ability to vastly improve the effect of 
numerous compounds which are presently used as antioxidants for organic 
materials. Thus, while the compounds of the present invention may be 
considered as stabilizers in their own right, their properties are such 
that they would be more conventionally classified as "synergists", in 
that, when combined with known stabilizers they exhibit the ability to 
increase stabilization to a degree far exceeding that which would be 
expected from the additive properties of the individual components. 
The compounds of the instant invention may be used with stabilizers (i.e. 
antioxidants, U.V. absorbers and antiozonates) at a weight ratio of from 
1:50 to 50:1 synergist to stabilizer. However the maximum effectiveness of 
the stabilizer is usually achieved when a compound of the instant 
invention is used with a stabilizer at ratios varying from 1:10 to 10:1. 
The optimum ratio of a given combination varies depending on the organic 
material to be stabilized, the stabilizers used and the environment to 
which the organic material is to be exposed. It should be appreciated that 
one or more compounds of the instant invention may be combined with one or 
more stabilizers of different types, (i.e. phenolics and amines). 
The stabilization system according to the present invention (synergist plus 
stabilizer) can be added to said organic materials in known ways. For 
instance, it can be combined with the organic material either after 
dilution with a solvent, while in latex form, or directly as is. More 
preferably, the compounds of the instant invention are added to a 
polymerization recipe so that the synergistic functionality becomes 
covalently bonded or attached to the polymeric backbone through the 
polymerizable moiety of the synergist. It has also been found advantageous 
to prepare masterbatches of highly loaded polymers so as to allow for 
mixing with unmodified polymers to achieve the desired and required level 
of stabilization system. It is also possible to graft the compounds of the 
instant invention to polymers alone or in combination with other reactive 
stabilizers known to the art. This may be accomplished on polymers in 
latex form, in solution or during mastication. 
These polymers, whether liquid or solid, have a special advantage in that 
the age resistant portion (stabilization system) is not extractable, and 
therefore the polymeric compositions are highly resistant to aging even 
after repeated exposure to aqueous detergent solutions or dry-cleaning 
fluids. This feature is especially significant where polymers are used in 
foam backings for rugs and where polymers are used in solution or latex 
form to treat fabrics, since such products are often exposed to aqueous 
detergent solutions or dry-cleaning fluids. This feature is also 
significant where factors such as contact with lubricating oils or 
exposure to high vacuum conditions are a consideration. The instant 
invention will also have utility in coating applications such as paints. 
Polymers, oils, resins and waxes subject to deterioration that can be 
conveniently protected by the stabilization system described herein, 
either as physical admixtures or mixing with masterbatches, include 
substituted and unsubstituted, saturated and unsaturated, natural and 
synthetic polymers, oils and waxes. The oxidizable natural polymers 
include natural rubber in its various forms, e.g., pale crepe and smoked 
sheet, and balata and gutta percha. The oxidizable synthetic polymers are 
prepared from a single monomer (homopolymer) or a mixture of two or more 
copolymerizable monomers (copolymer) wherein the monomers are combined in 
a random distribution or block form. The monomers may be substituted or 
unsubstituted and may possess one or more double bonds, for example, diene 
monomers, both conjugated and nonconjugated, and monoolefins including 
cyclic and acyclic monoolefins, especially vinyl and vinylidene monomers. 
Examples of conjugated dienes are 1,3-butadiene, isoprene, chloroprene, 
2-ethyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene and piperylene. Examples 
of nonconjugated dienes are 1,4-pentadiene, 1,4-hexadiene, 1,5-hexadiene, 
dicyclopentadiene, 1,5-cyclooctadiene and ethylidene norbornene. Examples 
of acyclic monoolefins are ethylene, propylene, 1-butene, isobutylene, 
1-pentene and 1-hexene. Examples of cyclic monoolefins are cyclopentene, 
cyclohexene, cycloheptene, cylooctene and 4-methyl-cyclooctene. Examples 
of vinyl monomers are styrene, acrylonitrile, acrylic acid, ethylacrylate, 
vinyl chloride, butylacrylate, methyl vinyl ether, vinyl acetate and vinyl 
pyridine. Examples of vinylidene monomers are .alpha.-methylstyrene, 
methacrylic acid, methyl methacrylate, itaconic acid, ethyl methacrylate, 
glycidyl methacrylate and vinylidene chloride. Representative examples of 
the synthetic polymers used in the practice of this invention are 
polychloroprene; homopolymers of a conjugated 1,3-diene such as isoprene 
and butadiene, and in particular, polyisoprenes and polybutadienes having 
essentially all of their repeat units combined in a cis-1,4 structure; 
copolymers of a conjugated 1,3-diene such as isoprene and butadiene with 
up to 50 percent by weight of at least one copolymerizable monomer 
including ethylenically unsaturated monomers such as styrene or 
acrylonitrile; butyl rubber, which is a polymerizable product of a major 
proportion of a monoolefin and a minor proportion of a multiolefin such as 
butadiene or isoprene; polyurethanes containing carbon to carbon double 
bonds; and polymers and copolymers of monoolefins containing little or no 
unsaturation, such as polyethylene, polypropylene, ethylene propylene 
copolymers and terpolymers of ethylene, propylene and a nonconjugated 
diene such as dicyclopentadiene, 1,4-hexadiene, ethylidene norbornene and 
methylene norbornene and polyester. 
It has been found that addition of the synergist and the stabilizer 
(stabilization system) to organic materials in the range from 0.1 to 10.0 
parts per hundred of organic material by weight will effectively protect 
the organic material from deterioration. As described above, the 
stabilization system according to the present invention comprises the 
novel compounds expressed by general formulae I through XII combined with 
a known stabilizer. The stabilization system of the present invention 
demonstrates activity superior to that of most conventional systems 
prepared by combining two or more commercial stabilizers. In addition, the 
instant invention has the added benefit of a synergist that cannot be 
extracted by solvents. Further, the synergists of the instant invention 
when forming part of the polymeric backbone will not migrate and therefore 
will not be lost to volatility or bloom. 
BEST MODE FOR CARRYING OUT THE INVENTION 
Preparation of Synergists 
The novel compounds of this invention are generally prepared by reacting an 
acrylate with a thiol, thereafter reacting the resultant product with a 
compound that contains a polymerizable moiety. The following is a more 
specific reaction scheme for compounds of the invention and certain 
control or comparative compounds. All parts are parts by weight unless 
otherwise noted. 
EXAMPLE 
I. Preparation of 2-hydroxyethyl 3-(dodecythio)-2-methylpropionate 
To a flask equipped with a stirrer, water condenser and thermometer was 
charged 34 grams of 2-hydroxyethyl-methacrylate, 50 grams of 
dodecanethiol, 4 drops of Triton.TM. B (Trademark for a 40% solution of 
benzyltri-methylammonium hydroxide in methanol) and 1 pellet of KOH. The 
temperature rose from 20.degree. C. to 58.degree. C. Gas chromatography 
indicated the reaction was 99% complete after 20 minutes. 
II. Preparation of 2-[3-dodecylthio)-2-methylpropionyl-oxy]ethyl 
methacrylate--Compound of Structural Formula IV 
50 grams of the product from Example I, 37 mls. of triethylamine and 75 mls 
of toluene were charged to a reaction vessel. Twenty-two grams of 
methacryloyl chloride was added slowly with stirring below 20.degree. C. 
The product was washed with water several times after the reaction was 
determined to be complete by gas chromatography. The volatiles were 
removed by distilling the product to a pot temperature of 210.degree. C. 
and column temperature of 105.degree. C. at 2.6 mm Hg. 
III. Preparation of 2-hydroxyethyl 3-(n butylthio)-2-methylpropionate 
To the reactor described in Example I was charged 55 grams of 
2-hydroxyethylmethacrylate, 37 grams of n-butanethiol, 1.5 grams of 
Triton.TM. B and 3 pellets of KOH. The flask contents were reacted at 
40.degree. to 50.degree. C. until the reaction was complete by gas 
chromatography analysis. The yield was theoretical. 
IV. Preparation of 2-[3-(butylthio)-2-methylpropionyloxy]ethyl 
methacrylate--Compound of Structural Formula IV 
40 grams of the product from Example III, 25 mls of triethylamine, 75 mls 
of toluene and 50 mls of tetrahydrofuran were charged to a flask. Twenty 
grams of methacryloyl chloride was then added over a 10 minute period 
below 20.degree. C. After one hour of reaction time the reaction was 
complete. The product was washed several times with water and then the 
volatiles were removed by distilling at 92.degree. C. and 15 mm Hg. 
V. Preparation of methyl 3-(2-hydroxyethylthio) propionate 
47 grams of methylacrylate, 55 mls of methanol and 0.75 grams of KOH 
(dissolved in 8 mls water) were charged to the reactor of Example I. 39 
grams of 2-mercaptoethanol was added at 33.degree. C. over a 50 minute 
period. After reacting for two additional hours at 40.degree. C., the 
volatiles were removed under vacuum at 76.degree. C. The product was 
further dried with Na.sub.2 CO.sub.3. 
VI. Preparation of methyl 3-(2-methacryloyloxyethylthio) 
propionate--Control/Comparative Compound 
40 grams of the product prepared in Example V, 30 grams triethylamine and 
50 mls of tetrahydrofuran were charged to a reactor. Below 40.degree. C. 
was then added slowly 27 grams of methacryloyl chloride. The product was 
washed several times with water after gas chromatography indicated the 
reaction was complete. The volatiles were removed with a rotary 
evaporator. The structure was confirmed by NMR. 
VII. Preparation of methyl 3-(4-hydroxyphenylthio) propionate 
66 grams of 4-mercaptophenol, 100 mls tetrahydrofuran and 10 drops of 
Triton.TM. B were charged to a reactor. Fifty-one grams of methylacrylate 
was added slowly over a 30 minute period below 50.degree. C. TLC (thin 
layer chromatography) was used to determine when the reaction was 
complete. The volatiles were removed on a rotary evaporator. 
VIII. Preparation of methyl 3-(4-methacryloyloxyphenylthio) 
propionate--Compound of Structural Formula I 
30 grams of the product prepared in Example VII, 50 mls tetrahydrofuran, 30 
grams triethylamine and 100 mls benzene were charged to a reactor. Sixteen 
grams of methacryloyl chloride was added over a 15 minute period below 
33.degree. C. The product was washed with water when TLC analysis showed 
the reaction was complete. The volatiles were removed by a rotary 
evaporator. 
IX. Preparation of 2-hydroxyethyl 3-[(2-methoxycarbonyl)ethylthio]-2-methyl 
propionate 
46 grams of methyl 3-mercaptopropionate, 50 grams hydroxyethylmethacrylate, 
20 drops of Triton.TM. B and 3 pellets of KOH powder were charged to a 
reactor. The mixture was reacted at 70.degree. C. to 85.degree. C. until 
gas chromatography indicated the reaction was complete. 
X. Preparation of 
2-(methacryloxy)ethyl-3[(2-methoxycarbonyl)ethylthio]2-methyl 
propionate--Compound of Structural Formula VIII 
40 grams of the product prepared in Example IX, 60 mls tetrahydrofuran, 50 
mls toluene and 33 mls of triethylamine were charged to a reactor. Twenty 
grams of methacryloyl chloride was then added over a 5 minute period below 
38.degree. C. The product was washed with water after TLC analysis showed 
the product had formed. The volatiles were removed at 65.degree. C. on a 
rotary evaporator after adding 0.05 parts of BHT to avoid possible product 
polymerization. The structure was confirmed by NMR. 
XI. Preparation of methyl 3-(6-hydroxyhexylthio) propionate 
25 grams of 5-hexene-1-ol, 13.8 grams methyl 3-mercaptopropionate and 0.25 
grams AIBN were charged to a small bottle and agitated on a bottle roller 
for 21/2 hours at 70.degree. C. The product was then distilled to a pot 
temperature of 155.degree. C. and a column temperature of 70.degree. C. at 
7 mm Hg to remove the unreacted components. 
XII. Preparation of methyl 3-(6-methacryloylhexylthio) 
propionate--Control/Comparative Compound 
20 grams of the product prepared in Example XI, 14 grams triethylamine and 
50 grams of tetrahydrofuran were charged to the reactor described in 
Example I. Below 32.degree. C. was added 13.4 grams of methacryloyl 
chloride. The reactor contents were allowed to react 30 minutes longer and 
then diluted with hexane and washed with water. The volatiles were removed 
on a rotary evaporator. The product weight was 25 gms. 
POLYMERIZATION OF SYNERGISTS 
The aforementioned monomeric synergists of this invention and known 
monomeric age resistors may be polymerized by well known free radical 
emulsion polymerization techniques with one or more comonomers that are 
known to polymerize in free radical initiated polymerization systems. Some 
adjustments in the polymerization recipe and/or conditions may be 
necessary to obtain a satisfactory rate of polymer formation. Adjustments 
which may be necessary in the polymerization conditions to improve 
polymerization rates include adjusting the temperature of polymerization 
and/or adjusting the initiator level and/or adjusting the level of 
activator ingredients and/or changing the level of the molecular weight 
modifier. Solvents may also be required to obtain adequate solubility of 
the monomers with each other as well as to solubilize other ingredients 
when required. Some solvents, such as methyl ethyl ketone, 
dichloromethane, THF or isopropyl alcohol, can be used to advantage. These 
adjustments, where necessary, are to counteract the inhibitory effect of 
the monomeric age resistor and/or synergist and to insure its solubility 
in the polymerization system. 
Examples of free radical initiators that are useful in the practice of this 
invention are those known as "Redox" initiators, such as appropriate 
combinations of chelated iron salts, sodium formaldehyde sulfoxylate and 
organic hydroperoxides such as cumene and paramenthane hydroperoxides. 
Other initiators such as azoisobutyronitrile (AIBN), benzoyl peroxide, 
hydrogen peroxide and potassium persulfate may also be used, depending on 
the particular polymerization recipe. 
The monomeric age resistors and/or synergists used in the practice of this 
invention have certain chemical characteristics which promote their use in 
polymerization processes initiated by free radicals. By "free radical 
initiated systems" is meant systems wherein free radicals are generated by 
any of various processes such as thermal decomposition of various 
persulfate, perborate, peroxide, azo or azonitrile compounds; induced 
(catalytic or "Redox" promoted) decomposition of various persulfate, 
peroxide or hydroperoxide compounds and generation of free radicals by 
exposure of the system to high energy radiation such as radiation from a 
radioactive source or ultraviolet light. Such systems are very well known 
in the art and are widely used commercially, e.g., in the preparation of 
SBR (styrene/butadiene copolymers). 
Very effective free radical polymerization initiators when used under 
appropriate conditions, are compounds such as t-butyl hydroperoxide and 
paramenthane hydroperoxide, and even hydrogen peroxide. These compounds 
perform very effectively when used in polymerization recipes containing 
appropriate levels of supporting ingredients. By "supporting ingredients" 
is meant those materials often referred to as activators in emulsion, or 
other systems, where required. U.S. Pat. No. 3,080,334 describes some of 
these materials at column 5, lines 20-26. Such materials can also be 
referred to as catalyst activators. The term "Redox Polymerization" is 
often used where the complete initiation system includes a Redox system, 
i.e., reducing agents and oxidizing agents in a proportion that yields 
polymerization initiating species. These initiator systems are well known 
in the art. Various organic initiators are described by J. Brandrup and E. 
H. Immergut, Polymer Handbook (John Wiley & Sons), 1965, pages II-3 to 
II-51. 
Various initiator system components are described at column 4, lines 14 to 
32, in U.S. Pat. No. 3,080,334. The monomeric synergists of the present 
invention can be used in emulsion polymerization systems to produce 
polymers of numerous and varying types. 
The principles of emulsion polymerization are discussed in references such 
as "Synthetic Rubber" by G. S. Whitby, Editor-in-Chief, John Wiley and 
Sons, 1954, particularly Capter 8, and "Emulsion Polymerization" by F. A. 
Boxey et al, Vol. IX of "High Polymers", Interscience Publishers Inc. 
1955. Some specialized applications of these principles are indicated in 
U.S. Pat. Nos. 3,080,334; 3,222,334; 3,223,663; 3,468,833 and 3,099,650. 
Representative of comonomers that can be used with the monomeric synergists 
of this invention are polymerizable unsaturated hydrocarbons, both 
substituted and unsubstituted, including conjugated diene monomers, such 
as butadiene-1,3; 2-chlorobutadiene-1,3; isoprene; 2-ethylbutadiene-1,3; 
2,3-dimethyl butadiene-1,3; piperylene; and hexadienes and copolymerizable 
monoolefins including vinyl and vinylidene monomers such as styrene, 
.alpha.-methylstyrene, dimethylstyrene, divinyl benzene, vinyl chloride, 
vinyl acetate, vinylidene chloride, methylmethacrylate, ethylacrylate, 
glycidyl methacrylate, the vinylpyridines including 2-vinyl pyridine, 
5-methyl-2-vinyl pyridine, 4-vinyl pyridine and 2-vinyl-5-ethyl pyridine, 
(3-isopropenyl-.alpha.,.alpha.-dimethyl-benzyl isocynate, acrylonitrile, 
methacrylonitrile, methacrylic acid, acrylic acid, itaconic acid, 
isocyanatoethyl-methacrylate and 2-hydroxyethyl-methacrylate. Also useful 
are the polymerizable stabilizers known in the art such as those described 
in U.S. Pat. Nos. 3,658,789, 3,767,628 and 4,213,892. 
In these polymerizations, the monomer charge weight ratio is normally from 
0.10/99.9 to 50/50 monomeric stabilizing system (synergist or synergist 
plus antioxidant) to comonomers (i.e. styrene and butadiene). The ratio 
may be as high as 60/40 or even higher. A charge ratio of 0.5/99.5 to 
20/80 is preferred. Ratios will vary depending on the amount of synergist 
and age resistor desired to be bound and on the reactivity ratios of the 
monomers in the particular polymerization system used and whether or not a 
masterbatch is desired. It should be appreciated that the stabilizing 
system may contain only synergist and that the compounds of this invention 
may be homopolymerized and blended with another polymer to achieve the 
desired level of protection or copolymerized only with an antioxidant and 
blended with another polymer. 
The polymers resulting from the free radical polymerizations of monomeric 
systems containing the monomeric synergists of the present invention will 
contain at least one segmeric unit based on the formulae I-XII in that the 
unsaturated portion (&gt;C.dbd.C&lt;) has become part of the polymeric backbone. 
GRAFTING OF SYNERGISTS 
As previously mentioned the compounds of this invention can also be grafted 
onto a polymer. The following examples illustrate this grafting technique. 
XIII. Grafting Onto NBR-Compound of Structural Formula IV 
Fifty-three grams of an NBR polymer (19% solids) was placed in a 
1.2.times.10.sup.-4 m.sup.3 (4 oz.) bottle. To the reaction bottle was 
added a solution containing 3 grams of the monomer prepared in Example II, 
emulsified in 5 g. of a saturated potassium oleate solution (surfactant). 
The bottle was purged with nitrogen and then injected with 3.3 mls. of a 
3% AIBN in toluene/THF (0.1 g AIBN) solution. The bottle was rotated in a 
70.degree. C. water bath for 16 hours and then coagulated in isopropyl 
alcohol. The polymer product was extracted with methanol. Elemental 
analysis showed the sample contained 1.85% sulfur. Hence the NBR product 
contained 21.9 parts by weight of 
2-[3-dodecylthio)-2-methylpropionyloxy]-ethylmethacrylate grafted onto it. 
XIV. Grafting Onto NBR-2-[3-(butylthio)-2-methyl propionyloxy]ethyl 
methacrylate 
Same as example XIII except that 3 grams of the monomer prepared in Example 
IV was emulsified with 5 grams of 10% Igepal.TM. CO-850 (a polyethoxy 
surfactant). The NBR polymer after coagulation and extraction was found to 
contain 1.78% sulfur. The resulting polymer product thus contained 21.1 
parts by weight of the monomer prepared in example IV grafted onto its 
structure. 
XV. Grafting Onto SBR 
Same as Example XIII except 40 grams of an SBR1006 (25% solids) type latex 
(a styrene butadiene copolymer hot emulsion polymerization with 23.5% 
styrene content) was used. The extracted polymer was found to contain 
1.85% by weight sulfur by elemental analysis. The polymer product thus 
contained 21.6 parts of the monomer prepared in Example II grafted to it. 
XVI. Grafting of 2-[3-(butylthio)-2-methylpropionyloxy]ethyl 
N-[.alpha.,.alpha.-dimethyl-3-isopropenylbenzyl]carbamate 
Into a bottle was weighed 19.4 grams of the product prepared in example 
III, 21 grams of (3-isopropenyl)-.alpha.,.alpha.-dimethylbenzylisocyanate, 
41 grams of toluene, 0.1 g. dibutyltindilaurate and 3 drops of 
triethylamine. The reaction bottle was rotated at 25.degree. C. on a 
bottle roller. The reaction was followed by thin layer chromatography. The 
solvent was distilled off when the reaction was complete. The yield was 40 
grams. 
Forty grams of an SBR1006 type latex (25% solids) was charged to the 
reaction bottle. A solution composed of 3 grams of the product prepared 
above emulsified in 5 grams of a saturated potassium oleate solution was 
added to the bottle. The bottle was purged with nitrogen and then injected 
with 3.3 mls. of a 3% AIBN in Toluene/THF (0.1 g. AIBN) solution. The 
bottle was rotated in a 70.degree. C. water bath for 16 hours and then 
coagulated in isopropyl alcohol. The sample was extracted with methanol. 
The extracted polymer contained 0.3% of sulfur due to the successful 
grafting of the monomer. The polymer product thus contained 2.23 parts of 
the grafted synergist. 
The preferred method for incorporating the compounds of the instant 
invention involves the polymerization method which entails the use of the 
synergist as a monomer in a free radical polymerization reaction. 
To afford adequate protection against degradation the polymers should 
contain from about 0.10 part to about 10.0 parts by weight of the segmeric 
form of the synergist per 100 parts by weight of the polymer, although 
from about 0.50 part to about 5.0 parts is normally satisfactory, from 
about 0.50 part to about 3.0 parts being preferred. As much as 20 parts, 
30 parts, 50 parts and more of the polymer may consist of the synergist 
segmeric unit while the lower limit may be 0.50 part to 0.10 part and 
lower. However, as the amount of bound synergist increases the physical 
characteristics of the polymer are altered accordingly. 
Where it is desired that the polymer act as a polymeric age resistor which 
may be blended with unstabilized polymers the polymer should normally 
contain greater amounts of the monomeric stabilization system. The 
remainder of the polymer is comprised preferably of the segmeric form of 
at least one conjugated diene monomer and/or the segmeric form of at least 
one vinyl monomer. Preferably the polymers contain at least 50 percent by 
weight of the segmeric form of a diene, preferably a conjugated diene such 
as butadiene or isoprene. 
XVII. Polymerization of Synergistic Monomers 
To test some of the compounds as polymerizable synergists, a 
butadiene/styrene/synergist terpolymer was prepared using the following 
recipe: 
______________________________________ 
Ingredients Parts 
______________________________________ 
Butadiene 68.50 
Styrene 21.50 
Monomer from Example IV 10.00 
Tertiary Dodecyl Mercaptan .50 
Potassium salt of Resinate (80%) 
2.76 
KOH .38 
Tallow Fatty Acid 1.95 
Sodium salt of condensed naphthalene sulfonic acid 
.08 
Water 200.00 
H.sub.2 SO.sub.4 .01 
FeSO.sub.4 7H.sub.2 O .015 
Chelating Agent* .063 
Sodium Formaldehyde Sulfoxylate 
.056 
Sodium Dimethyldithiocarbamate (35%) 
.558 
Diethylhydroxyamine .185 
______________________________________ 
*90/10 mixture of tetrasodium salt of ethylenediaminetetraacetic acid and 
monosodium salt of N,N--di(hydroxyethyl)glycine 
The resulting polymer was coagulated, extracted 48 hours with methanol in a 
Soxhlet extractor, dried and analyzed to determine the amount of bound 
synergist. The polymer was dissolved in toluene, and unstabilized SBR 1006 
cement was blended with the terpolymer cement to yield final synergist 
contents of 0.25, 0.50 and 0.75 parts by weight. These samples were then 
stabilized with an antioxidant. Films were cast from toluene cements and 
oxygen absorption measurements were made on the films. 
XVIII. Testing of Compounds 
The activity of the compounds and mixtures of this invention was determined 
by means of the oxygen absorption test. The testing procedure is of the 
type described in detail in Ind. & Engr. Chem., Vol. 43, p. 456 (1951) and 
Ind. & Engr. Chem., Vol. 45, p. 392 (1953). 
From the data in Table I it is quite evident that the compounds of this 
invention synergistically enhance the antioxidative activity of commercial 
amine antioxidants. In addition, the commercially accepted synergistic 
DLTDP failed to perform as well as the compounds of this invention. 
TABLE I 
__________________________________________________________________________ 
Hours to Absorb 
Compound - All Parts By Weight 
1.0% O.sub.2 By Weight 
1.5% O.sub.2 By Weight 
__________________________________________________________________________ 
(1) 
1.0 pt WS-29* (control).sup.+ 
724 1226 
(2) 
0.5 pt WS-29 (control).sup.+ 
692 1018 
(3) 
0.75 pt WS-29 and 0.25 pt bound synergist from Ex IV 
854 1271 
(4) 
0.5 pt WS-29 and 0.5 pt bound synergist from Ex IV 
969 1350 
(5) 
0.25 pt WS-29 and 0.75 pt bound synergist from Ex IV 
912 1438 
(6) 
1.0 pt WS-300** (control).sup.+ 
444 758 
(7) 
0.75 pt WS-300 and 0.25 pt bound synergist from Ex IV 
462 795 
(8) 
0.5 pt WS-300 and 0.5 pt bound synergist from Ex IV 
533 842 
(9) 
0.25 pt WS-300 and 0.75 pt bound synergist from Ex IV 
600 937 
(10) 
0.5 pt WS-29 and 0.5 pt DLTDP*** 
758 1169 
__________________________________________________________________________ 
*WS-29 is a styrenated diphenylamine stabilizer marketed by The Goodyear 
Tire & Rubber Company under the tradename Wingstay 29. 
**WS300 is N--phenylN'--(1,3dimethylbutyl)-p-phenylenediamine marketed by 
The Goodyear Tire & Rubber Company under the tradename Wingstay 300. 
***DLTDP is dilauryl 3,3thiodipropionate the most widely used commercia 
synergist. 
.sup.+ Control polymers contained no bound synergist. 
XIX. 
The compounds prepared in Examples II and IV were individually polymerized 
in an SBR recipe similar to that described in Example XVII. The resulting 
extracted polymers contained 3.75 parts of bound synergist from Example II 
and 3.0 parts of bound product from Example IV, respectively. The 
synergist containing polymers were each dissolved in toluene and then 
diluted with an SBR 1006 toluene cement to reach the desired level of 
bound synergist in each test sample. Wingstay.TM. C, a phenolic 
stabilizer, was used as the antioxidant/costabilizer in the testing. 
Polymer cements containing various ratios of these stabilizers were cast 
on aluminum sheets and evaluated at 100.degree. C. by oxygen absorption 
testing until 1.0% oxygen had been absorbed by each test sample. 
The data from the testing of the bound synergist and two non-bound 
synergists is presented in Table II. The data indicates that the 
synergists of this invention, whether bound of non-bound, exhibit 
synergism with a commercially accepted phenolic antioxidant. 
TABLE II 
__________________________________________________________________________ 
Oxygen Absorption Data 
Compound - Parts By Weight per 100 Parts Rubber 
Hours to Absorb 1.0% O.sub.2 By 
__________________________________________________________________________ 
Weight 
(1) 
2.0 pt SBR bound monomer from Example II + 0.5 pt Wingstay 
755 
(2) 
1.5 pt SBR bound monomer from Example II + 0.5 pt Wingstay 
634 
(3) 
1.0 pt SBR bound monomer from Example II + 0.0 pt Wingstay 
69 
(4) 
0.75 pt SBR bound monomer from Example II + 0.25 pt Wingstay 
368 
(5) 
0.50 pt SBR bound monomer from Example II + 0.50 pt Wingstay 
476 
(6) 
0.25 pt SBR bound monomer from Example II + 0.75 pt Wingstay 
416 
(7) 
0.0 pt SBR bound monomer from Example II + 1.0 pt Wingstay 
168 
(8) 
2.0 pt SBR bound monomer from Example IV + 0.5 pt Wingstay 
566 
(9) 
1.5 pt SBR bound monomer from Example IV + 0.5 pt Wingstay 
589 
(10) 
1.0 pt SBR bound monomer from Example IV + 0.0 pt Wingstay 
67 
(11) 
0.75 pt SBR bound monomer from Example IV + 0.25 pt Wingstay 
275 
(12) 
0.50 pt SBR bound monomer from Example IV + 0.50 pt Wingstay 
494 
(13) 
0.25 pt SBR bound monomer from Example IV + 0.50 pt Wingstay 
454 
(14) 
*0.5 pt non-bound monomer from Example II + 0.5 pt Wingstay 
457 
(15) 
*0.5 pt non-bound monomer from Example IV + 0.5 pt Wingstay 
590 
__________________________________________________________________________ 
*Samples were not extracted. 
XX. 
Polymer solutions were prepared the same as described in Example XIX except 
an SBR polymer cement containing a bound antioxidant, 2,6 
ditertiarybutyl-4-hydroxyphenyl methacrylate was used instead of Wingstay 
C as the costabilizer. The recipe for copolymerizing the phenolic 
antioxidant monomer was similar to that described in Example XVII. (See 
U.S. Pat. No. 3,953,402.) Polymer cements containing 11/2 grams of 
stabilized polymer were cast on 12 cm by 17 cm aluminum sheets and dried. 
The dried samples were soxhlet solvent extracted with hot methanol for 0, 
8, 16 and 24 hours. The dried samples were then evaluated by oxygen 
absorption testing at 100.degree. C. until they had absorbed 1.0% O.sub.2 
by weight. The data in Table III demonstrates that: 
(1) The synergist and phenolic antioxidant act synergistically to prolong 
the life of the polymer. 
(2) If either the phenolic antioxidant and/or the synergist are not 
chemically attached to the polymer chain, they are rapidly extracted and 
lost. 
(3) If the antioxidant and the synergist are chemically attached to the 
polymer, they cannot be lost due to solvent extraction and volatility. 
(4) The commercial and closest prior art synergist dilauryl 
thiodipropionate (DLTDP) is very easily extracted (Samples 17 and 18 from 
Table III) because it cannot be chemically attached to the polymer. 
TABLE III 
__________________________________________________________________________ 
Oxygen Absorption Data of SBR 1006 
Hours Extracted 
Hours to Absorb 
With Methanol 
1.0% O.sub.2 by weight 
Stabilizer System Used 0 8 16 24 
at 100.degree. C. 
__________________________________________________________________________ 
(1) 
1.0 pt bound Compound A X no data *(360) 
(2) 
1.0 pt bound Compound A X 358 
(3) 
1.0 pt bound Compound A X 348 
(4) 
1.0 pt bound Compound A X 356 
(5) 
1.0 pt non-bound Compound A X 350 
(6) 
1.0 pt non-bound Compound A X 2 
(7) 
1.0 pt non-bound Compound A X 1 
(8) 
1.0 pt non-bound Compound A X 1 
(9) 
.5 pt bound Compound A + .5 pt bound Compound B 
X no data *(560) 
(10) 
.5 pt bound Compound A + .5 pt bound Compound B 
X 561 
(11) 
.5 pt bound Compound A + .5 pt bound Compound B 
X 642 
(12) 
.5 pt bound Compound A + .5 pt bound Compound B 
X 692 
(13) 
.5 pt non-bound Compound A + .5 pt non-bound Compound 
X no data *(560) 
(14) 
.5 pt non-bound Compound A + .5 pt non-bound Compound 
X 2 
(15) 
.5 pt non-bound Compound A + .5 pt non-bound Compound 
X 3 
(16) 
.5 pt non-bound Compound A + .5 pt non-bound Compound 
X 2 
(17) 
.5 pt bound Compound A + .5 pt DLTDP 
X 670 
(18) 
.5 pt bound Compound A + .5 pt DLTDP X 250 
No Stabilizer Used 30 
__________________________________________________________________________ 
Compound A = 2,6ditertiarybutyl-4-hydroxyphenyl methacrylate 
Compound B = Synergist prepared in Example II 
*No data due to O.sub.2 absorption apparatus failure expected value in ( 
)'s. 
XXI. 
The monomer prepared in Example VI was copolymerized in an SBR recipe 
similar to that described in Example XVII. The polymer was extracted and 
analyzed to determine the amount of bound compound VI. In a similar 
recipe, 2,6 di-tertiary-butyl-4-hydroxyphenyl methactylate was 
copolymerized in an SBR recipe. The polymer was extracted and then 
analyzed to determine the amount of each monomer incorporated into the SBR 
chains. Each polymer was dissolved in toluene and adjusted to the desired 
stabilizer concentration with a toluene cement of SBR 1006. 
The monomers were also evaluated in their non-bound forms. The data in 
Tables IV, V and VI show that the monomer from Example VI is an active 
synergist when used as an additive, like dilaurylthiodipropionate (DLTDP), 
(in a non-bound form). However, the monomer prepared in Example VI is 
totally non-effective once it is chemically attached to a polymer. Hence, 
we see that all alkylthioesters are not active as polymer bound 
synergists. 
TABLE IV 
______________________________________ 
Hours to Absorb 1.0% O.sub.2 at 100.degree. C. 
Parts of Bound 
Synergist Hours to 
Compound A Absorb 1% O.sub.2 
______________________________________ 
Parts of Non-Bound 
Antioxidant Compound B 
1.54 0 30 
1.23 .2 112 
.93 .4 256 
.62 .6 171 
.31 .8 305 
0 1.0 332 
Parts of Non 
Bound Wingstay C 
1.23 .2 126 
.93 .4 153 
.62 .6 223 
.31 .8 265 
1.0 241 
______________________________________ 
Compound A Monomer prepared in Example VI 
Compound B 2,6 ditertiary4-hydroxyphenyl methacrylate 
No synergism is shown as long as the monomer prepared in Example VI is 
chemically bound to the polymer. 
TABLE V 
______________________________________ 
Hours to Absorb 1.0% Oxygen at 100.degree. C. In A System 
Containing Wingstay C and Non Polymer Bound Compound A 
Parts of Parts of Non Hours to 
Wingstay C Bound Compound A 
Absorb 1.0% O.sub.2 
______________________________________ 
1.0 0 241 
.8 .2 504 
.6 .4 588 
.4 .6 542 
.2 .8 361 
0 1.0 93 
______________________________________ 
The sulfenic acid which results when Compound A (synergist prepared in 
Example VI) is used in a nonbound form is active as an antioxidant 
synergist. 
TABLE VI 
______________________________________ 
Oxygen Absorption Data of a System 
Containing Non-Bound Antioxidant and Synergist 
Parts of Non Parts of Non Hours to 
Bound Compound B 
Bound Compound A 
Absorb 1.0% O.sub.2 
______________________________________ 
0 1.0 73 
.25 .75 416 
.50 .50 542 
.75 .25 502 
1.00 0 336 
______________________________________ 
Compound A = Synergist prepared in Example VI 
Compound B = 2,6 ditertiarybutyl4-hydroxyphenyl methacrylate 
Wingstay C = A phenolic stabilizer made by The Goodyear Tire & Rubber 
Company 
XXII. Polymerization of Synergist in an NBR Recipe 
In the manner of Example XVII, an acrylonitrile-butadiene-synergist (of 
Example IV) terpolymer is prepared. The ingredients and the proportions 
are listed below. 
______________________________________ 
Ingredients Parts 
______________________________________ 
Acrylonitrile 29.0 
Butadiene 61.0 
Synergist from Example IV 10.0 
Tertiary dodecyl mercaptan 0.5 
Potassium soap of disproportioned rosin acids 
1.5 
Sodium salt of tallow fatty acids 
1.4 
Sodium salt of condensed naphthalene sulfonic acid 
0.12 
Na.sub.2 SO.sub.4 1.5 
Water 100.0 
Chelating Agent 0.027 
FeSO.sub.4.7H.sub.2 O 0.006 
Sodium formaldehyde sulfoxylate 
0.074 
Na.sub.2 S.sub.2 O.sub.4 0.006 
Paramenthane hydroperoxide 0.08 
______________________________________ 
The soaps are placed in 95 parts of the water along with the sodium salt of 
the sulfonic acid and the Na.sub.2 SO.sub.4 and charged to the reactor. 
The mercaptan dissolved in 13.3 parts of the acrylonitrile, is then 
charged. This is followed by the addition of the synergist in 13.3 parts 
of acrylonitrile. The butadiene is then added. The chelating agent, iron 
compound, sulfoxylate and Na.sub.2 S.sub.2 O.sub.4 is then added in 5 
parts of water. Finally the hydroperoxide is added in 1.4 parts of the 
acrylonitrile. Initial polymerization temperature is 21.degree. C. The 
temperature is increased to 38.degree. C. as conversion progressed. The 
hydroperoxide is charged as 0.04 parts initially and as two 0.02 part 
increments during the course of the polymerization. When conversion 
reaches the desired level a shortstop is added. 
XXIII. 
A series of polymers were prepared using a monomer ratio of 65 parts of 
butadiene, 25 parts of styrene and 10 parts of total stabilizer (synergist 
plus antioxidant). A recipe similar to the ones previously described was 
used. The polymerizable antioxidant monomer 
N-(4-anilinophenyl)methacrylamide was used as the co-stabilizer in this 
study. Table VII shows the exact monomer charge for each antioxidant 
polymer prepared. The polymers were coagulated and then soxhlet extracted 
with hot methanol for 48 hours. Elemental sulfur and nitrogen content 
analysis were used to determine the amount of stabilizer monomer 
incorporated in the SBR after extraction. This data is shown in Table 
VIII. 
TABLE VII 
______________________________________ 
Parts of Monomers Charged in the Polymerization 
Sample 
A B C D E F G 
______________________________________ 
Styrene 25 
Butadiene 65 
Synergist From Ex III 
10 5 
Synergist From Ex IV 10 
Synergist From Ex XII 10 
Synergist from Ex VIII 10 5 
Synergist from Ex VI 10 
N--(4-anilinophenyl) 5 5 
methacrylamide 
______________________________________ 
TABLE VIII 
______________________________________ 
Analyzed Parts of Bound Stabilizer Monomers 
From the Polymers Prepared in Table VII 
Stabilizer 
Monomer Used A B C D E F G 
______________________________________ 
Synergist From Ex II 
1.75 2.1 
Synergist From Ex IV 7.51 
Synergist From Ex XII 8.19 
Synergist From Ex VIII 8.22 6.0 
Synergist From Ex VI 9.12 
N--(4-anilinophenyl) 4.4 3.4 
methacrylamide 
______________________________________ 
The polymers described in Tables VII and VIII were evaluated by Oxygen 
Absorption testing. The antioxidant and synergist containing polymers were 
dissolved in toluene and then diluted with an SBR 1006 toluene cement to 
obtain the desired polymer bound stabilizer concentrations are listed in 
Table IX. 
TABLE IX 
______________________________________ 
Oxygen Absorption Data for Polymers 
Prepared in Tables VII and VIII 
Stabilization System 
Hours to Absorb 1.0% O.sub.2 
______________________________________ 
.64 pt Bound Synergist VIII + 
694 
.36 pt Bound Antioxidant* 
.32 pt Bound Synergist II + 
819 
.68 pt Bound Antioxidant* 
.36 pt Bound Antioxidant* 
189 
.50 pt Bound Antioxidant* 
251 
.68 pt Bound Antioxidant* 
329 
1.0 pt Bound Antioxidant* 
448 
.64 pt Bound Synergist VIII 
26 
.32 pt Bound Synergist II 
30 
______________________________________ 
*N--(4anilinophenyl)methacrylamide 
XXIV. 
The polymer prepared as described in Example XXIII, Tables VII and VIII, 
Sample B, was used in an oxygen absorption study with Wingstay.TM. 300 and 
Agerite.TM. Resin D (polymerized 2,2,4-trimethyl-1,2-dihydroquinoline) to 
demonstrate synergism. The polymer bound synergist (monomer from Example 
IV) and the amine costabilizer were diluted with SBR 1006 to reach the 
desired stabilizer levels. Dilaurylthiodipropionate (DLTDP) was used as a 
non polymer bound synergist control. 
______________________________________ 
Hours to Absorb 
1.0% 2.0% 
______________________________________ 
0.1 pt Wingstay .TM. 300 + 
742 941 
.5 pt SBR Bound Example IV Monomer 
0.1 pt Wingstay .TM. 300 + 
903 1,166 
1.0 pt SBR Bound Example IV Monomer 
0.5 pt SBR Bound Example IV Monomer 
35 63 
1.0 pt SBR Bound Example IV Monomer 
175 226 
0.1 pt Wingstay .TM. 300 + .5 pt DLTDP 
766 1,025 
0.1 pt Wingstay .TM. 300 + 1.0 pt DLTDP 
960 N/A 
0.1 pt Wingstay .TM. 300 
461 N/A 
0.1 pt Agerite .TM. Resin D + 
903 1,055 
.5 pt SBR Bound Example IV Monomer 
0.1 pt Agerite .TM. Resin D 
62 109 
No antioxidant or synergist 
4 
______________________________________ 
The data clearly shows that the SBR bound synergistic monomer from Example 
IV acts synergistically with Wingstay.TM. 300 and also Agerite.TM. Resin 
D. The bound synergists are just as effective as the non bound DLTDP. 
However, the polymer bound synergist of this invention cannot be lost by 
migration, volatility or extraction. DLTDP is easily extracted from 
polymers. 
INDUSTRIAL APPLICABILITY 
From the testing data obtained it is evident that the compounds disclosed 
herein significantly enhance the stability of polymers when combined with 
known antioxidants. The industrial applications are readily apparent in 
light of the high synergistic activity of these novel compounds when used 
in conjunction with known antioxidants. Use of the compounds of this 
invention would significantly reduce the amount of costly antioxidant that 
is needed to provide the desired stability of the organic material. 
While certain representative embodiments and details have been shown for 
the purpose of illustrating the invention, it will be apparent to those 
skilled in this art that various changes and modifications may be made 
herein without departing from the scope of this invention.