# Patent

## Title
Catalytic polymerization process

## Abstract

This invention relates to a process for controlling the architecture of copolymers of at least two unsaturated monomers, made by free-radical polymerization in the presence of a cobalt-containing chain transfer agent, including the control of molecular weight, degree of branching and vinyl end group termination, by varying at least one of the variables of molar ratio of monomers, their relative chain transfer constants, polymerization temperature and degree of conversion and amount of cobalt chain transfer agent; and polymers made thereby.

## Background
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a divisional of application Ser. No. 09/125,467, filed Aug. 19, 1998, granted as U.S. Pat. No. 6,624,261 on Sep. 23. 2003 ,which is 35 U.S.C. § 371 of PCT/US97/02912, filed Feb. 18, 1997 that claims benefit of provisional Application Ser. No. 60/012,131, filed Feb. 23, 1996.


BACKGROUND OF THE INVENTION
Catalytic chain transfer is an effective way to control the molecular weight of polymers of methacrylates and styrenes. It is known that chain transfer catalysis (CTC) products contain a terminal vinylidene bond. This feature makes these products attractive as macromonomers for a variety of applications. However, CTC has not been known to be applicable for reduction of molecular weight in the polymerizations of other vinylic monomers such as acrylates.
Copolymerizations of methacrylate monomers with monosubstituted monomers in the presence of cobalt have been described in the art. However, the monosubstituted monomer is almost always present as a minor component. U.S. Pat. No. 4,680,354 describes molecular weight reduction using various Co(II) complexes in MMA-BA, MMA-EA and MMA-BA-St copolymerizations, wherein the abbreviations represent:
MMA=methyl methacrylate
BA=butyl acrylate
EA=ethyl acrylate
St=styrene.
U.S. Pat. No. 5,324,879 describes molecular weight reduction with Co(III) complexes in EA, St, and vinyl acetate (VAc) polymerizations, and MMA-EA copolymerization.
U.S. Pat. No. 4,680,352 describes molecular weight reduction and macromonomer (polymers or copolymers with unsaturated end-groups) synthesis in copolymerizations with acrylates and styrene with various Co(II) complexes. Various terpolymerizations are cited therein; however, no evidence of the nature or existence of terminal double bonds is given.
Gruel et al., Polymer Preprints, 1991, 32, p. 545, reports the use of Co(II) cobaloximes in low conversion St-MMA copolymerizations at low temperatures with end group analysis.
The references cited above cover the copolymerization of acrylates and styrene with methacrylate monomers, but do not disclose synthetic conditions for production of high purity macromonomers based on acrylates and styrene, nor branching of the resulting products. The conditions disclosed are unlikely to yield high purity macromonomers for systems composed predominantly of monosubstituted monomers. Disclosed temperatures of less than 80° C. are likely to provide substantial amounts of undesired graft copolymer at high conversion rates.
SUMMARY OF THE INVENTION
This invention concerns an improvement in a process for the free-radical polymerization of at least two unsaturated monomers to form a polymer whose molecular architecture comprises properties of molecular weight, branching, and vinyl-terminated end groups, the monomers having the formula

CH2═CXY

wherein

X is selected from the group consisting of H, CH3, and CH2OH;
Y is selected from the group consisting of OR, O2CR, halogen, CO2H, COR, CO2R, CN, CONH2, CONHR, CONR2 and R′;
R is selected from the group consisting of substituted and unsubstituted alkyl, substituted and unsubstituted aryl, substituted and unsubstituted heteroaryl, substituted and unsubstituted aralkyl, substituted and unsubstituted alkaryl, and substituted and unsubstituted organosilyl, the substituents being the same or different and selected from the group consisting of carboxylic acid, carboxylic ester, epoxy, hydroxyl, alkoxy, primary amino, secondary amino, tertiary amino, isocyanato, sulfonic acid and halogen; and the number of carbons in said alkyl groups is from 1 to 12; and
R′ is selected from the aromatic group consisting of substituted and unsubstituted aryl, substituted and unsubstituted heteroaryl, the substituents being the same or different and selected from the group consisting of carboxylic acid, carboxylic ester, epoxy, hydroxyl, alkoxy, primary amino, secondary amino, tertiary amino, isocyanato, sulfonic acid, substituted and unsubstituted alkyl, substituted and unsubstituted aryl, substituted and unsubstituted olefin and halogen;
by contacting said monomers with a cobalt-containing chain transfer agent and a free radical initiator at a temperature from about 80° to 170° C.;
the improvement which comprises controlling polymer architecture by introducing into the presence of the chain transfer agent at least one each of monomers A and B in the molar ratio of A:B, said molar ratio lying in the range of about 1,000:1 to 2:1, wherein for monomer A Xis H and for monomer B X is methyl or hydroxymethyl; by one or more of the following steps:

    
    
        I decreasing the ratio of A:B from about 1,000:1 toward 2:1;
        II increasing the temperature from above 80° C. toward 170° C.;
        III increasing the conversion of monomer to polymer toward 100% from less than about 50%;
        IV decreasing the ratio of the chain transfer constant of A:B to below 1; and
        V increasing the concentration of cobalt chain transfer agent;

whereby:

    
    


to effect lower molecular weight, employ at least one of steps I, II, IV and V;
to effect a higher degree of vinyl-terminated end groups, employ at least one of steps I, II, IV, and V; and
to effect increased branching,employ at least one of steps I, II, IV, and V with step III.
The nature of the derived products changes as a function of time. In the initial stages, linear macromonomers with one monomer-A in the terminal position can be obtained as essentially the only product. If the cobalt CTC catalyst levels are relatively low then CTC does not occur after every B-monomer insertion and the product mixture can include monomer-B units in the polymer chain as well as in the terminal position.
Cobalt chain transfer agent is employed in the form of cobalt complexes. Their concentrations are provided in the Examples in terms of ppm by weight of total reaction mass. Concentration will vary from 10 ppm to 1,500 ppm, preferably 10 to 1,000 ppm.
Later in the course of the reaction, when the concentration of the two above products is increased, then they can be reincorporated into a growing polymer chain. Thus, mono-branched product is obtained in the later stages of the reaction, usually around 90% conversion. At conversions above 95%, branches begin to appear on the branches, and the polymer becomes hyperbranched as conversions approach 100%.
Preferred monomers A are selected from the group consisting of acrylates, acrylonitrile and acrylamides;
and preferred monomers B are selected from the group:


    
    
        a) substituted or unsubstituted α-methylstyrenes;
        b) substituted or unsubstituted alkyl methyacrylates, where alkyl is C1–C12;
        c) methacrylonitrile;
        d) substituted or unsubstituted methacrylamide;
        e) 2-chloropropene,
        f) 2-fluoropropene,
        g) 2-bromopropene,
        h) methacrylic acid,
        i) itaconic acid,
        j) itaconic anhydride, and
        k) substituted or unsubstituted styrenics.
    
    


If branched polymers are the desired product, it is possible to initiate the described process in the presence of preformed macromonomers. They can be of the type described in this patent. They can also be macromonomers based entirely upon methacrylates or the related species described previously in U.S. Pat. No. 4,680,354. Such a process would lead to products fitting the description above, but would allow for greater control over the polymer end-groups.
The branched polymers made by said process are polymers of this invention having the formula:




    Y is as earlier defined;
    n=1–20, m=1–5, p=1–20, and n+m+p≧3, and
    Z is selected from the group CH2CHYCH3, CH2CMeYCH3, and, optionally,






    m′=0–5, p′=0–20; n+m′+p′≧2;
    and if m or m′>1, the m or m′ insertions respectively are not consecutive.


This invention also concerns a process comprising selecting A and B so the ratio of their chain transfer constants is less than 1, whereby functionality derived from Monomer B will be located on the vinyl-terminated end of the polymer.
This invention also concerns an improved process for the free-radical polymerization of at least two unsaturated monomers having the formula

CH2═CXY

wherein

X is selected from the group consisting of H, CH3, and CH2OH;
Y is selected from the group consisting of OR, O2CR, halogen, CO2H, CO2R, CN, CONH2, CONHR, CONR2, COR and R′;
R is selected from the group consisting of substituted and unsubstituted alkyl, substituted and unsubstituted aryl, substituted and unsubstituted heteroaryl, substituted and unsubstituted aralkyl, substituted and unsubstituted alkaryl, and substituted and unsubstituted organosilyl, the substituents being the same or different and selected from the group consisting of carboxylic acid, carboxylic ester, epoxy, hydroxyl, alkoxy, primary amino, secondary amino, tertiary amino, isocyanato, sulfonic acid and halogen, and the number of carbons in said alkyl groups is from 1 to 12; and
R′ is selected from the aromatic group consisting of substituted and unsubstituted aryl, substituted and unsubstituted heteroaryl, the substituents being the same or different and selected from the group consisting of carboxylic acid, carboxylic ester, epoxy, hydroxyl, alkoxy, primary amino, secondary amino, tertiary amino, substituted and unsubstituted alkyl, substituted and unsubstituted aryl, substituted and unsubstituted olefin and halogen;
by contacting said monomers with a cobalt-containing chain transfer agent and a free radical initiator at a temperature from about 80° C. to 170° C.;
the improvement which comprises controlling molecular weight of the polymer architecture by introducing into the presence of the chain transfer agent at least one each of monomers C and D in the molar ratio of C:D in the range of about 1,000:1 to 2:1, in which for monomer C, X is H and Y≠R′ and for monomer D, X is H and Y=R′ by:
decreasing the ratio of C:D from about 1,000:1 toward 2:1; or
increasing the temperature from above 80° C. toward 170° C.
Preferred monomers A are selected from the group consisting of acrylates, acrylonitrile and acrylamides;
and preferred monomers B are substituted and unsubstituted styrenics.
The polymers made by said process improvement are polymers of this invention having the formula:




where Y≠R′ and n≧1.

This invention also concerns a process improvement for polymerizing monomer(s) in the presence of an excess of a nonpolymerizable olefin, Y1Y2C═CY3Y4. The product in the initial stages of the polymerization will be composed primarily of




wherein:

Y1 and Y3, and optionally Y2 and Y4, are each independently selected from the group consisting of —CH(O), —CN, —C(O)OR5, —C(O)NR6R7, —CR8(O), alkyl, aryl, substituted alky, substituted aryl; or
where Y1 and Y3 or Y2 and Y4 are combined in a cyclic structure which includes any of the above functionalities, or can be —C(O)—(CH2)x—, —C(O)—O—(CH2)x—, —C(O)O—C(O)—, —C(O)(CH2)x—, —C(O)NR9—(CH2)x—, wherein x=1–12, R5, R6, R7, R8, or R9 are hydrogen, alkyl, aryl, substituted alkyl, or substituted aryl; and where at least one of Y1 and Y3 is selected from the group consisting of —CH(O), —CN, —C(O)OR5, —C(O)NR6R7, —CR8(O), aryl, substituted aryl; and the remaining of Y2 and Y4 are —H.
The polymers made by said process improvement are polymers of this invention produced at later stages of the polymerization process having the formula:




where Z=H, CH3, CH2CHYCH3, CH2CMeYCH3, or




k=0 or 1, n=0–20, m=0–5, p=0–20; and k+n+m+p≧2; if m>1, then it is not intended to imply that the m insertions are consecutive;
Y is selected from the group consisting of OR, O2CR, halogen, CO2H, COR, CO2R, CN, CONH2, CONHR, CONR2 and R′; and
Y1 to Y4 and R, and R′ are as defined above.


DETAILS OF THE INVENTION
We have discovered that, with addition of small amounts of an α-methylvinyl monomer and appropriate choice of reaction conditions, polymerization of monosubstituted monomers in the presence of a metal complex can provide high yield of macromonomers. These macromonomers can subsequently be used for the synthesis of a wide range of block and graft copolymers.
This invention concerns a method for the synthesis of (unsaturated macromonomers composed predominantly of monosubstituted monomers. The macromonomers are prepared by polymerizing a monosubstituted monomer as the major component (for example styrene) in the presence of a disubstituted α-methylvinyl monomer (for example, α-methylstyrene, herein also referred to as “AMS”) and a catalytic amount of a cobalt complex [for example, Co(II)(DMG-BF2)2] called CoII in Scheme 1. Reaction Scheme 1 illustrates the process where monomer A=styrene and monomer B=α-methylstyrene. The process is applicable to a wide range of monosubstituted monomers (for example acrylate esters, vinyl acetate (VAc)) and other non-α-methylvinyl monomers




In Scheme 1, “Ph” represents a phenyl group, and “m” designates the number of monomer units in the polymer, and is ≧1.
The key features of the invention are the addition of small amounts of α-methylvinyl monomers and the use of high reaction temperatures in the presence of chain transfer catalysts.
The incorporation of α-methylvinyl monomers into the recipe allows formation of the desired macromonomer end group. In the absence of the α-methylvinyl monomer, polymerization of monosubstituted monomers give polymers with internal double bonds (styrenic monomer) or a stable alkyl-cobalt species (acrylate monomers) as chain ends.
The use of high reaction temperatures (>100° C.) favors the formation of pure linear macromonomers from monosubstituted monomers (for example acrylates, vinyl esters, and styrene). At lower temperatures we have shown that the formed macromonomers can react further by copolymerization to give branched polymers. Even though the macromonomers can undergo further reaction, at reaction temperatures >100° C., the radicals so formed do not propagate to give branched polymers. Rather, they fragment to give back a macromonomer. It is possible that this chemistry will also reduce the polydispersity of the final product.
The invention also provides a route to block or graft copolymers as illustrated in Scheme 2. The product derived by copolymerization of the macromonomer in the presence of monomers can be determined by appropriate choice of the monomer and the reaction conditions.




block copolymer

In Scheme 2, “Ph” represents a phenyl group; “m”, “n” and “o” designate the number of monomer units in the polymer; and X and Y are as defined above.

We have demonstrated that styrene macromonomers prepared by the above mentioned copolymerization route give chain transfer (by an addition fragmentation mechanism) and have acceptable chain transfer constants at temperatures >100° C. They should therefore be useful in the preparation of block copolymers.
One further aspect of the invention is that by appropriate choice of the α-methylvinyl monomer the method is also a route to end-functional polymers. For example, use of a hydroxyethyl- or glycidyl-functional monomer would yield polymers with ω-hydroxy or ω-epoxy groups, respectively.
This method enables the versatility and robustness of the cobalt technology to be utilized to form macromonomers that are comprised predominantly of monosubstituted monomers. Additionally, it provides the key step in a new and less expensive route to end-functional and block or graft copolymers based on monosubstituted monomers. Copolymerizations of monosubstituted monomers with other α-methylvinyl monomers (for example α-methylstyrene) in the presence of cobalt are contemplated.
The choice of the α-methyvinyl comonomer is important in macromonomer synthesis. It must be chosen so that the reactivity towards cobalt (“catalytic chain transfer constant”) of the derived propagating species is substantially greater than that of the propagating species derived from the monosubstituted monomer.
Two factors influence this reactivity.

    
    
        a) The rate of the chain transfer reaction between the propagating species and the cobalt complex;
        b) The relative concentrations of the propagating species. This is determined not only by the monomer concentration but also by the propagation rate constants and reactivity ratios.
    
    


While methacrylate esters can be used as α-methylvinyl comonomers (see examples), in copolymerization with styrene, the values of the reactivity ratios and propagation rate constants will favor the formation of styryl chain ends. The product then has an internal rather than the desired terminal double bond. Methacrylate esters are acceptable comonomers in, for example, acrylate polymerizations.
Thus, the use of α-methylvinyl comonomers (for example, α-methylstyrene, methacrylonitrile) which have low propagation rate constants and high chain transfer rate constants are preferred.
There are substantial cost improvements over alternative technologies which involve the use of stoichiometric amounts of an organic transfer agent. The ability to use acrylate/styrenic rich macromonomers, in contexts similar to those developed for methacrylate monomers products by cobalt mediated processes, for example, in graft, star, block and branched copolymer syntheses, further extends the value of the process.
The nature of the derived products changes as a function of time. In the initial stages, the product




can be obtained as essentially the only product. If the cobalt CTC catalyst levels are relatively low then CTC does not occur after every B-monomer insertion and the product mixture can include:





Later in the course of the reaction, when the concentration of the two above products is increased, they can be reincorporated into a growing polymer chain. Thus, the product




where Z can include —H, —CH3, CH2CHYCH3, CH2CMeYCH3, or





is obtained. In the early stages of the reaction, Z is most often H, but as the reaction proceeds toward 90% conversion, Z begins to include more of the higher molecular weight species as branches. At conversions above 95%, branches begin to appear on the branches, and the polymer becomes hyperbranched as conversions approach 100%.

Metal complexes are those that give catalytic chain transfer with α-methylvinyl monomers. Examples include, but are not limited to, cobalt(II) and cobalt(III) chelates:




    
    
        Co(II)(DPG-BF2)2 J=K=Ph, L=ligand
        CO(II)(DMG-BF2)2 J=K=Me, L=ligand
        Co(II)(EMG-BF2)2 J=Me, K=Et, L=ligand
        Co(II)(DEG-BF2)2 J=K=Et, L=ligand
        Co(II)(CHG-BF2)2 J=K=—(CH2)4—, L=ligand
    
    






    
    
        QCo(III)(DPG-BF2)2 J=K=Ph, R=alkyl, L=ligand
        QCo(III)(DMG-BF2)2 J=K=Me, R=alkyl, L=ligand
        QCo(III)(EMG-BF2)2 J=Me, K=Et, R=alkyl, L=ligand
        QCo(III)(DEG-BF2)2 J=K=Et, R=alkyl, L=ligand
        QCo(III)(CHG-BF2)2 J=K=—(CH2)4—, R=alkyl, L=ligand
        QCo(III)(DMG-BF2)2 J=K=Me, R=halogen, L=ligand
    
    


L can be a variety of additional neutral ligands commonly known in coordination chemistry. Examples include water, amines, ammonia, phosphines, The catalysts can also include cobalt complexes of a variety of porphyrin molecules such as tetraphenylporphyrin, tetraanisylporphyrin, tetramesitylporphyrin and other substituted species.
α-Methylvinyl monomers (B monomers) have the general structure




where Y is as described above in the “Summary”. R is an optionally substituted alkyl (such as fluoroalkyl, hydroxyalkyl, or epoxyalkyl), organosilyl, or aryl group. Preferred examples of α-methylvinyl monomers (B monomers) include methacrylate esters, α-methylstyrene and methacrylonitrile.

“A” monomers have the general structure:




where Y is as described above in the “Summary”.
The enhanced utility of the polymerization method discussed in this invention is that it extends each of these general CTC methodologies:

    
    
        i) molecular weight control is extended from methacrylates and styrenes to include acrylates, vinyl esters, and other higher activity monomer species;
        ii) macromonomer synthesis is extended to the monomers in (i) while retaining the desirable vinyl termination of the resulting species;
        iii) end-functional polymer synthesis is also extended to the monomers in (i);
        iv) the use of macromonomers as chain transfer agents is extended to include monomer classes heretofore unavailable through CTC technology; and
        v) not only are a wider range of block and graft copolymers available through the use of CTC technology, but now it is possible to prepare branched and even hyperbranched species through single-pot reactions.
    
    


It is preferred to employ free-radical initiators and solvents in the process of this invention. The process can be run in batch, semi-batch, continuous, bulk, emulsion or suspension mode.
Most preferred A-monomers are:

    methyl acrylate, ethyl acrylate, propyl acrylate (all isomers), butyl acrylate (all isomers), 2-ethylhexyl acrylate, isobornyl acrylate, acrylic acid, benzyl acrylate, phenyl acrylate, acrylonitrile, glycidyl acrylate, 2-hydroxyethyl acrylate, hydroxypropyl acrylate (all isomers), hydroxybutyl acrylate (all isomers), diethylaminoethyl acrylate, triethyleneglycol acrylate, N-tert-butyl acrylamide, N-n-butyl acrylamide, N-methyl-ol acrylamide, N-ethyl-ol acrylamide, trimethoxysilylpropyl acrylate, triethoxysilylpropyl acrylate, tributoxysilylpropyl acrylate, dimethoxymethylsilylpropyl acrylate, diethoxymethylsilylpropyl acrylate, dibutoxymethylsilylpropyl acrylate, diisopropoxymethylsilylpropyl acrylate, dimethoxysilylpropyl acrylate, diethoxysilylpropyl acrylate, dibutoxysilylpropyl acrylate, diisopropoxysilylpropyl acrylate, vinyl acetate, styrene, diethylamino styrene, P-methylstyrene, vinyl benzoic acid, vinylbeuzinsulfonic acid, vinyl propionate, vinyl butyrate, vinyl benzoate, vinyl chloride, vinyl fluoride, vinyl bromide.


Most preferred B-monomers are:

    methyl methacrylate, ethyl methacrylate, propyl methacrylate (all isomers), butyl methacrylate (all isomers), 2-ethylhexyl methacrylate, isobornyl methacrylate, methacrylic acid, benzyl methacrylate, phenyl methacrylate, methacrylonitrile, alpha methyl styrene, trimethoxysilylpropyl methacrylate, triethoxysilylpropyl methacrylate, tributoxysilylpropyl methacrylate, dimethoxymethylsilylpropyl methacrylate, diethoxymethyl-silylpropylmethacrylate, dibutoxymethylsilylpropyl methacrylate, diisopropoxymethylsilylpropyl methacrylate, dimethoxysilylpropyl methacrylate, diethoxysilylpropyl methacrylate, dibutoxysilylpropyl methacrylate, diisopropoxysilylpropyl methacrylate, isopropenyl butyrate, isopropenyl acetate, isopropenyl benzoate, isopropenyl chloride, isopropenyl fluoride, isopropenyl bromideitaconic aciditaconic anhydridedimethyl itaconate, methyl itaconateN-tert-butyl methacrylamide, N-n-butyl methacrylamide, N-methyl-ol methacrylamide, N-ethyl-ol methacrylamide, isopropenylbenzoic acid (all isomers), diethylamino alphamethylstyrene (all isomers), para-methyl-alpha-methylstyrene (all isomers), diisopropenylbenzene (all isomers), isopropenylbenzene sulfonic acid (all isomers), methyl 2-hydroxymethylacrylate, ethyl 2-hydroxymethylacrylate, propyl 2-hydroxymethylacrylate (all isomers), butyl 2-hydroxymethylacrylate (all isomers), 2-ethylhexyl 2-hydroxymethylacrylate, isobornyl 2-hydroxymethylacrylate, and TMI® dimethyl Meta-Isopropenylbenzyl Isocyanate.


Preferred C monomers are those from the list of A monomers minus the styrenic family.
Preferred D monomers include the following styrenes:

    styrene, vinyl benzoic acid (all isomers), diethylamino styrene (all isomers), para-methylstyrene (all isomers), and vinyl benzene sulfonic acid (all isomers),


Typical products of the reaction at lower conversions include the linear products from methyl acrylate and methyl methacrylate:




from butyl acrylate and alpha-methylstyrene:




from hydroxyethyl acrylate and alpha-methylstyrene:




from vinyl benzoate and butyl methacrylate:




Typical products of the reaction at lower conversions include the linear products from butyl acrylate and methyl methacrylate:




from methyl acrylate and alpha-methylstyrene:





When the polymerization (for example butyl acrylate as A-monomer and methyl methacrylate as B-monomer) is carried out in the presence of a nonpolymerizable olefin such as 2-pentenenitrile, the product in the initial stages of the polymerization will be:




and later in the polymerization the product will be:




It becomes impractical to draw schematics of any of the higher degrees of branching that are obtained as the conversion of the polymerization approaches 100%.
Oligomers, macromonomers and polymers made by the present process are useful in a wide variety of coating and molding resins. Other potential uses can include cast, blown, spun or sprayed applications in fiber, film, sheet, composite materials, multilayer coatings, photopolymerizable materials, photoresists, surface active agents, dispersants, adhesives, adhesion promoters, coupling agents, compatibilizers and others. End products taking advantage of available characteristics can include, for example, automotive and architectural coatings or finishes, including high solids, aqueous or solvent based finishes. Polymers, such as those produced in this invention, will find use in, for example, structured polymers for use in pigment dispersants.
K+IDS mass spectroscopy is an ionization method that produces pseudomolecular ions in the form of [M]K+ with little or no fragmentation. Intact organic molecules are desorbed by rapid heating. In the gas phase, the organic molecules are ionized by potassium attachment. Potassium ions are generated from an aluminosilicate matrix that contains K2O. All of these experiments were performed on a Finnegan Model 4615 GC/MS quadrupole mass spectrometer (Finnegan MAT (USA), San Jose, Calif.). An electron impact source configuration operating at 200° C. and a source pressure of <1×10−6 torr was used. MALDI was also performed on this instrument.
All MW and DP measurements were based on gel permeation chromatography (GPC) using styrene as a standard.
Definitions
The following abbreviations have been used and are defined as:

    TAPCo=meso-tetra(4-methoxyphenyl)porphyrin-Co; VAZO®-88=1,1′-azobis(cyclohexane-1-carbonitrile) (DuPont Co., Wilmington, Del.); VRO-110=2,2′-azobis(2,4,4-trimethylpentane) (Wako Pure Chemical Industries, Ltd., Osaka, Japan);
    DP=degree of polymerization. Mn is number average molecular weight and Mw is weight average molecular weight. AIBN is azoisobutyronitrile. THF is tetrahydrofuran. MA=methylacrylate.


EXAMPLES
Examples 1–9
Synthesis of Low Molecular Weight Styrene Macromonomers
AMS Comonomer
Feed Polymerization
Examples 1–3 and Control 1 show that molecular weight control is obtained in the absence of added α-methylstyrene. The products have structure 1 with an internal double bond and do not function as macromonomers.




Solution polymerization of styrene with α-methylstyrene (10:1) and iPrCo(III)(DMG-BF2)2 isopropylcobalt(III)(DMG) (100 ppm) in n-butyl acetate at 125° C.

















n-butyl acetate
20.04
g



styrene (sty)
10.03
g



α-methylstyrene
1.00
g


Shot:
iPrCo(III)(DMG-BF2)2
1.4
mg



n-butyl acetate
5.00
g


Feed 1:
1,1′-azobis(4-cyclohexanecarbonitrile)
0.093
g


(0.063 mL/min
n-butyl acetate
6.73
g


over 120 min)
iPrCo(III)(DMG-BF2)2
4.6
mg


Feed 2:
styrene
13.57
g


(0.139 mL/min
α-methylstyrene
1.57
g


over 120 min)









The butyl acetate was degassed in a 5 neck 250 mL reactor, equipped with condenser, stirred, and N2 purge. The monomers were added and degassed for a further 10 minutes. The reactor was heated to reflux (ca 125° C.) and the shot of iPrCo(III)(DMG-BF2)2/solvent added. The monomer and initiator feeds were started immediately. The reactor was sampled at regular intervals to monitor intermediate molecular weights (GPC, THF) and conversions (1H NMR, CDCl3). A sample of this low viscosity yellow liquid was precipitated into a twenty fold excess of methanol, and the macromonomer recovered as a fine white powder. {overscore (M)}n 1270, {overscore (M)}w/{overscore (M)}n 1.43, 34% conversion. The precipitated samples were examined by 1H NMR (200 MHz, CDCl3) to establish the nature of the chain ends.
The unsaturated end groups give rise to signals as follows: styryl end group internal double bond (1): δ6.1 —CH(Ph)—CH═CH-Ph; δ3.1 CH(Ph)—CH═CH-Ph. Alpha methyl styrene-(AMS)-derived terminal methylene double bond (2): δ4.8 1H and δ5.2 1H, —C(Ph)═CH2 (the ratio of the signals at δ6.1 and δ4.8 was found to give the best estimate of terminal double bond content. Although this utilises a signal on the fringe of the broad aromatic resonance δ7.6–7.2, a series of comparisons of the 1H-NMR molecular weights calculated from the end groups with those obtained by GPC showed that this gave better results than the signal at δ3.1). This may be due to the internal double bond product being a mixture of (1) and (3).







TABLE 1.1





Polymerization of styrene in presence of AMS and iPrCo(III)


(DMG-BF2)2 at 125° C.
























Time
[Co(III)]
Sty:







Example
(min)
ppm
AMS
{overscore (M)}n
{overscore (M)}w
{overscore (M)}w/{overscore (M)}n
Conv.1 %
[22]2 %





1
 30
100
—
1050
2290
2.18





 60
100

1150
2540
2.21
3



120
100

1100
2590
2.18
5



ppt
100

1630

1.69

0


2
 60
50
—
2010
4150
2.06
3



120
50

1720
3980
2.30
5



ppt
50

1940

2.03

0


3
 60
25
—
3270
11153
3.41
3



120
25

2710
9540

3.52
5



ppt
25
—
2750

3.26

0






Time
[Co(III)]
Sty:







Example
(min)
ppm
AMS
{overscore (M)}n
{overscore (M)}w
{overscore (M)}w/{overscore (M)}n
Conv.1 %
[22] %D





Control 1
 60
0
—
32230
54760
1.70
2




120
0

33830
59450
1.76
4



180
0

38060
63750
1.68
5



240
0

39510
67150
1.70
6



300
0

37420
67630
1.81
7



360
0

39420
67070
1.70
8
0


4
 30
100
10:1
730
1840
2.38



 60
100

740
1670
2.25
1



120
100

690
1430
2.06
3



ppt
100

1270

1.43

32


5
 60
50
10:1
1170
2540
2.17
2



120
50

1040
2300
2.21
4



ppt
50

1470

1.80

56


6
 60
25
10:1
1370
2890
2.11
2



120
25

1270
2690
2.11
3



ppt
25

1660

1.89
65


Control 2
 20
0
10:1
19696
50460
2.56
n.d



 40
0

14860
37950
2.55
n.d



 60
0

17060
38890
2.28
1



120
0

24430
42040
1.72
3



240


27440
51420
1.87
4



360
0

29400
52930
1.80
6
0


7
 60
100
 5:1
380
930
2.45



120
100

140
870
2.10



ppt
100

1310

1.83
—


8
 60
50
 5:1
810
1670
2.06
1



120
50

780
1530
1.96
2



ppt
50

1180

1.53

68


9
 60
25
 5:1
1760
3480
1.98
2



120
25

1640
3160
1.93
3



ppt
25

2140

1.60

100


Control 3
 60
0
 5:1
16740
32450
1.94



120
0

19540
35020
1.79



ppt
0

19570

1.83

0





1Determined by 1H NMR


2% 2, remainder is 1 and 3 estimated by 1H NMR






Examples 10–12
Synthesis of High Molecular Weight Styrene Macromonomers
AMS Comonomer
Feed Polymerization
These Examples were run according to the same procedure of Examples 1 through 3.







TABLE 1.2







Polymerization of styrene in presence of AMS and iPrCo(III)(DMG-


BF2)2 at 125° C. Numbers in parenthesis indicate


reaction times.















reaction
[Co(III)]
Sty/AM



% terminal


Ex.
time (h)
(ppm)
S
{overscore (M)}nc
{overscore (M)}/{overscore (M)}
% conv.
alkene

















10
2
8
5/1
7455 (120)
2.4
14
—




(0.13/0.37)3

9442 (ppt)
1.95

>705


114
1
8
5/1
4648 (60)
1.81
12
—




(0.13/0.37)3

5160 (ppt)
1.64

>705


12
2
13
5/1
2660 (120)
1.87
20
—




(0.25/0.75)3

3300 (ppt)
1.63

>705





3amount, in mg, added in (shot/feed).


4rate of cobalt complex feed twice that for example 10.


5internal methylene was not visible in the 1H-nmr spectrum.






Examples 13–18, Control 4–6
Synthesis of Styrene Macromonomers
AMS Comonomer
Batch Polymerizations in Sealed Tube—Effect of Reaction Temperature
Batch polymerizations were conducted in sealed tubes to establish the effect of temperature on macromonomer purity (% 2). Molecular weights and macromonomer purities are similar to those obtained in the feed polymerization experiments (refer Table 1.1).
A mixture of styrene (1.3 g, 12.5 mmol), α-methylstyrene (0.15 g, 1.27 mmol) (monomer ratio: 10/1), n-butyl acetate (3 g), VR®-110 (8.9×10−5 g, 20 ppm) and iPrCo(III)(DMG-BF2)2 (for concentrations see Table 1.3) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 125° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.







TABLE 1.3







Batch polymerization of styrene in presence of AMS and


iPrCo(III)(DMG-BF2)2 at 125° C. with VR ®-110 initiator














Sty/




%



AMS
[Co(III)]


%
terminal


Example
ratio
ppm
{overscore (M)}n
{overscore (M)}w/{overscore (M)}n
conv
AMS
















Control 4
10/1
0
64547
1.72
5–9
—


Control 5
 5/1
0
53498
1.77
4–7
—


13
10/1
100
445
1.61
1–4
36


14
10/1
50
751
1.76
4–6
39


15
10/1
25
1408
1.79
7–9
54
















TABLE 1.4







Batch polymerization of styrene in presence of AMS and


iPrCo(III)(DMG-BF2)2 at 80° C. with AIBN initiator.














Sty/AM
[Co(III)]


%
% terminal


Example
ratio
ppm
{overscore (M)}n
{overscore (M)}w{overscore (M)}n
conv
AMS6
















Control 6
10/1
0
32,600
1.97
4
0


16
10/1
100
660
1.30
5
22


17
10/1
50
1090
1.52
7
33


18
10/1
25
1456
1.63
7
45





6Calculated as [terminal AMS units]/[terminal AMS units + terminal Sty units] × 100. From 1NMR.






Examples 19–22, Control 7–9
Synthesis of Styrene Macromonomers
AMS Comonomer
Batch Polymerizations in Sealed Tube—Effect of Cobalt Complex
A mixture of styrene (1.0 g, 9.6 mmol), α-methylstyrene (0.12 g, 0.96 mmol) (monomer ratio: 10/1), n-butyl acetate (2 g), VR®-110 (3.12×10−4 g, 100 ppm) and the cobalt species (for all experiments 50 ppm, 2.44×10−7 mol of cobalt species was used) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 125° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuao to a residue which was analysed by 1H-nmr and GPC.







TABLE 1.5







Batch polymerization of styrene in presence of AMS and various


cobalt complexes at 125° C. with VR ® 110 initiator.





















%









term-









inal



Co
[Co]



%
AMS


Example
species7
ppm
Mn
Mw
PD
conv
units8

















Control 7
Co(III)DMG
0
58,288
104,916
1.8
13
0


19
′′
50
1065
1730
1.62
19
71


Control 8
Co(III)DEG
0
72,284
125,129
1.73
15
0


20
′′
50
1388
2368
1.7
19
85


Control 9
Co(II)DPG
0
71,869
122,098
1.7
12
0


21
′′
50
1454
2532
1.74
23
91


22
Co(III)DMG
50
1470
—
1.8
39
74



Feed Expt9





7Co(III)DMG = iPrCo(III)(DMG-BF2)2, Co(III)DEG = MeCo(III)(DEG-BF2)2, Co(IIIDPG Co(II)(DPG-BF2)2.


8Calculated as [terminal AMS units]/[terminal AMS units + terminal Sty units] × 100 from NMR.


9Data ex Table 1.1






Examples 23–24, Control 10
Synthesis of Styrene Macromonomers
Methacrylate Comonomer
Feed Polymerization
The polymerization recipe for examples 23–24 and their control was similar to that given for Examples 1–3 with the modification that BMA was used in place of AMS. Conversions obtained are similar. Good molecular weight control is observed however little specificity for formation of a terminal macromonomer double bond is observed.







TABLE 1.7







Polymerization of styrene in presence of BMA and iPrCo(III)(DMG-


BF2)2 at 125° C. with 1,1′azobis(4-cyclohexanecarbonitrile) as initiator















Time
[Co(III)]







Sample
(min)
ppm
Sty:BMA10
{overscore (M)}n11
{overscore (M)}w
{overscore (M)}w/{overscore (M)}n
% Conv.12

















Control 10
 30
0
10:1
35870
60580
1.69
25



 60
0

34970
58090
1.66
35



120
0

36360
61770
1.70
51



ppt
0

35750

1.73


23
 30
100
10:1
11702
130
1.81
20



 60
100

1220
3410
1.82
37



120
100

1190
2230
1.88
51



ppt
100

1560

1.69


24
 60
25
10:1
4800
9440
1.97
38



120
25

3750
8290
2.21
53



ppt
25

4190
8270
1.97





10Molar ratio of comonomers


11Determined by GPC calibrated with narrow polydispersity polystyrene standards.


12Determined by 1H NMR






Examples 25–30
Synthesis of Styrene Macromonomers
Isopropenyl Acetate Comonomer
Batch Polymerization
Sty/iPA macromonomer formation at 80° C.: A mixture of styrene (1 g, 9.6 mmol), isopropenyl acetate (0.19 g, 1.9 mmol) (monomer ratio: 5/1), n-butyl acetate (2 g), AIBN (3.19×10−4 g, 100 ppm) and isopropylcobalt(III)DMG (for concentrations see Table 1.8) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 80° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.
1H-nmr (d6-acetone): styryl end group internal double bond (1): δ6.1 —CH(Ph)—CH═CH-Ph; δ3.1 CH(Ph)—CH═CH-Ph.







TABLE 1.8







Sty/iPA macromonomer formation at 80° C. for 2 h with AIBN and


iPrCo(III)(DMG-BF2)2.





















%









terminal









iPA



Sty/iPA
Co(III)




%


Example
ratio
ppm
Mn
Mw
PD
conv 
unit13

















Control 11
5/1
0
57,425
91,753
1.6
6.00
0


25
5/1
400
338
364
1.07
4.00
0


26
5/1
100
698
1045
1.49
4.00
0


27
5/1
25
5188
11,611
2.24
6.00
0


Control 12
1/1
0
32,782
52,987
1.61
3.00
0


28
1/1
400
323
343
1.07
2.00
0


29
1/1
100
465
586
1.26
3.00
0


30
1/1
25
1560
2825
1.81
3.00
0





13No terminal alkene derived from iPA were detectable by 1H NMR.






Examples 31–45, Controls 13–16
Synthesis of Butyl Acrylate Macromonomers
AMS Comonomer at 80° C.
Batch Polymerization—Effect of Comonomer and Complex Concentration
A mixture of butyl acrylate (1.3 g, 10 mmol), a-methylstyrene (50 mg, 0.4 mmol) (monomer ratio: 25/1), n-butyl acetate (2 g), AIBN (3.74×10−4 g, 100 ppm) and isopropylcobalt(III)DMG (for concentration see Table 2.1) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 80° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.
1H-nmr (d6-acetone): d 0.9, CH3; 1.25, CH2; 1.5, CH2; 1.95, CH; 2.3, backbone CH2; 2.55, allyl CH2; 3.95, OCH2; 5.0, vinyl H; 5.2, vinyl H; 7.15–7.25, ArH.







TABLE 2.1







Polymerization of butyl acrylate in presence of AMS and


iPrCo(III)(DMG-BF2)2 at 80° C.
















BA/AM
Co(III)


%
% term.
% AMS
% term.


Ex.
S ratio
ppm
{overscore (M)}n14
PD
Conv
AMS units15
inc.16
alkene17


















Ctrl 13
 5/1
0
23,500
1.75
3
0
39
0


31
 5/1
100
475
1.20
3
64
43
100


32
 5/1
50
487
1.20
4
60
38
100


33
 5/1
25
495
1.20
4
54
41
100


Ctrl 14
10/1
0
28,200
1.64
4
0
38
0


34
10/1
100
551
1.27
3
67
36
100


35
10/1
50
605
1.31
5
63
35
100


36
10/1
25
635
1.33
5
60
36
100


Ctrl 15
25/1
0
41,423
1.69
9
0
17
0


37
25/1
200
943
1.37
6
92
15
91


38
25/1
100
961
1.39
5
77
17
96


39
25/1
50
1062
1.42
6
71
18
100


40
25/1
25
1152
1.48
7
57
20
100


Ctrl 16
50/1
0
56,071
1.76
14
0
12
0


41
50/1
400
1168
1.64
10
78
9
80


42
50/1
200
1207
1.76
10
75
9
85


43
50/1
100
1481
1.80
13
61
9
91


44
50/1
50
1600
1.82
11
59
10
100


45
50/1
25
1876
1.96
11
45
10
100





14Polystyrene quivalents.


15Calculated as (terminal AMS units)/(total AMS units) × 100.


16Calculated as (total AMS units)/(total BA units + total AMS) × 100.


17Calculated as (terminal AMS units)/(terminal AMS units + terminal BA units) × 100.


A value of 100% indicates that terminal BA could not be detected by 1H NMR.






Examples 46–54, Controls 17, 18
Synthesis of Butyl Acrylate Macromonomers
AMS Comonomer at 125° C.
Batch Polymerization—Effect of Reaction Temperature
A mixture of butyl acrylate (1.3 g, 10 mmol), α-methylstyrene (50 mg, 0.4 mmol) (monomer ratio: 25/1), n-butyl acetate (2 g), VR®-110 (3.74×10−4 g, 100 ppm) and iPrCo(III)(DMG-BF2)2 (for concentration see Table 2.2) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 125° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.







TABLE 2.2







Polymerization of butyl acrylate in presence of AMS and


iPrCo(III)(DMG-BF2)2 at 125° C.





















% term.





BA/AMS
Co(III)


%
% AMS
% AMS
% terminal


Ex.
ratio
ppm
{overscore (M)}n
PD
conv
units18
inc.19
alkene20


















Control 17
25/1
0
18,069
1.77
36
0
13
0


46
25/1
200
973
1.58
19
77
12
85


47
25/1
100
967
1.73
29
68
13
93


48
25/1
50
1402
1.68
32
57
13
100


49
25/1
25
2230
2.10
3
23
20
100


Control 18
50/1
0
18,891
1.85
6
0
5
0


50
50/1
400
1069
1.65
21
84
6
not calc.


51
50/1
200
1200
1.72
21
72
7
73


52
50/1
100
1624
1.81
30
58
6
77


53
50/1
50
1948
1.92
32
55
6
87


54
50/1
25
3463
2.10
43
32
5
100





18Calculated as (terminal AMS units)/(total AMS units) × 100.


19Calculated as (total AMS units)/(total BA units + total AMS) × 100.


20Calculated as (terminal AMS units)/(terminal AMS units + terminal BA units) × 100.






Examples 55–58, Control 19
Synthesis of Butyl Acrylate Macromonomers
AMS Comonomer at 80° C.
Batch Polymerization—Effect of Cobalt Complex
A mixture of butyl acrylate (1.3 g, 10 mmol), a-methylstyrene (24 mg, 0.2 mmol) (monomer ratio: 50/1), n-butyl acetate (2 g), AIBN (3.74×10−4 g, 100 ppm) and MeCo(III)(DEG-BF2)2 (for concentration see table 2.3) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 80° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.







TABLE 2.3







Polymerization of butyl acrylate in presence of AMS and


MeCo(III)(DEG-BF2)2 at 80° C.





















% term.





BA/AMS
Co(III)


%
AMS
% AMS
% terminal


Ex.
ratio
ppm
{overscore (M)}n
PD
conv
Units21
inc.22
alkene23


















Control 19
50/1
0
49,342
1.74
11
0
25
0


55
50/1
200
1128
1.57
4
79
12
100


56
50/1
100
1162
1.66
5
75
12
100


57
50/1
50
1647
1.70
10
57
12
100


58
50/1
25
2369
1.85
11
31
13
100





21Calculated as (terminal AMS units)/(total AMS units) × 100.


22Calculated as (total AMS units)/(total BA units + total AMS) × 100.


23Calculated as (terminal AMS units)/(terminal AMS units + terminal BA units) × 100.






Examples 59–63, Control 20
BA/AMS Macromonomer Formation at 80° C. with Co(II)(DPG-BF2)2 
A mixture of butyl acrylate (1.3 g, 10 mmol), α-methylstyrene (24 mg, 0.2 mmol) (monomer ratio: 50/1), n-butyl acetate (2 g), AIBN (3.74×10−4 g, 100 ppm) and Co(II)(DPG-BF2)2 (for concentrations see Table 2.4) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 80° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced under vacuum to a residue which was analysed by 1H-nmr and GPC.







TABLE 2.4







Polymerization of butyl acrylate in presence of AMS (50/1) and


Co(II)(DPG-BF2)2 at 80° C.





















% term.

%



Co(II)



%
AMS
% AMS
terminal


Ex.
ppm
{overscore (M)}n
{overscore (M)}w
PD
Conv
units24
inc.25
alkene26


















Control 20
0
50,575
104,679
2.07
17
0
9
0


59
400
796
1262
1.58
1
79
11
89


60
200
864
1419
1.64
1
73
12
100


61
100
1064
1817
1.71
1
66
13
100


62
50
1126
1957
1.73
1
60
14
100


63
25
2076
5407
2.10
3
35
13
100





24Calculated as (terminal AMS units)/(total AMS units) × 100.


25Calculated as (total AMS units)/(total BA units + total AMS) × 100.


26Calculated as (terminal AMS units)/(terminal AMS units + terminal BA units) × 100.






Examples 64–68, Control 21
Synthesis of Butyl Acrylate Macromonomers
MAN Comonomer at 80° C.—Batch Polymerization
A mixture of butyl acrylate (1 g, 7.58 mmol), methacrylonitrile (51 mg, 0.758 mmol), n-butyl acetate (2 g), AIBN (3.54×10−4 g, 100 ppm) and iPrCo(III)(DMG-BF2)2 (for concentration see Table 2.5) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 80° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.
1H-nmr (CDCl3): d 0.95, CH3; 1.35, CH2; 1.65, CH2; 1.95, CH; 2.3, backbone CH2; 2.6, allyl CH2; 4.0, OCH2; 5.7, vinyl H; 5.85, vinyl H.







TABLE 2.5







Polymerization of butyl acrylate in presence of MAN and


iPrCo(III)(DMG-BF2)2 at 80° C.















BA/









MAN
[Co(III)]



%
% terminal


Ex.
Ratio
ppm
{overscore (M)}n
{overscore (M)}w
PD
conv.
methylene27

















Control
10/1
0
9306
17,653
1.90
8
0


21


64
10/1
400
669
1004
1.50
6
86


65
10/1
200
802
1179
1.47
7
87


66
10/1
100
959
1432
1.49
8
80


67
10/1
50
1036
1676
1.62
8
76


68
10/1
25
1301
2008
1.54
8
81





27Calculated as (terminal MAN units)/(terminal MAN units + terminal BA units) × 100.






Examples 69–83, Controls 22 to 24
Synthesis of Butyl Acrylate Macromonomers
MMA Comonomer at 60–125° C.—Batch Polymerization
BA/MMA Macromonomer Formation at BA/MMA 10/1
A mixture of butyl acrylate (1 g, 7.58 mmol), methyl methacrylate (76 mg, 0.758 mmol), n-butyl acetate (2 g), initiator (see Table 2.6 for initiator type) and isopropylcobalt(III)DMG (for concentration see Table 2.6) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at the indicated temperature for either 2 or 3 hours. The ampoule was rapidly cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.
1H-nmr (CDCl3): d 0.9, CH3; 1.35, CH2; 1.65, CH2; 1.85, CH: 2.25, backbone CH2; 2.55, allyl CH2; 3.6, OCH3; 4.0, OCH2; 5.5, vinyl H; 6.15, vinyl H.







TABLE 2.6







Polymerization of butyl acrylate in presence of MMA (10:1) and


iPrCo(III)(DMG-BF2)2 at various temperatures

















Temp ° C.
React.
Co(III)


%
% term.
% MMA
cal


Ex.
(initiator)
Time h
ppm
{overscore (M)}n
PD
conv
alkene28
incorp.292
ob



















Ctrl 22
(AIBN)
3
0
170,754
2.08
25
0
19
—


69
60
3
400
891
1.55
6
83
18
1.04


70
60
3
200
1051
1.56
5
87
19
1.05


71
60
3
100
1567
1.70
4
91
20
0.83


72
60
3
50
2610
1.80
7
100
19
0.98


73
60
3
25
7702
1.87
16
100
18
1.0 


Ctrl 23
(AIBN)
2
0
75,501
2.08
54
0
14
—


74
80
2
400
917
1.31
8
75
17
0.92


75
80
2
200
1196
1.43
10
86
17
0.93


76
80
2
100
1520
1.50
9
92
18
0.92


77
80
2
50
2602
1.66
21
94
17
1.00


78
80
2
25
12,117
1.82
53
100
14
1.09


Ctrl 24
(VR ®-110)
2
0
10,410
2.56
76
0
11
—


79
125
2
400
832
1.51
9
79
16
1.04


80
125
2
200
1032
1.73
15
87
17
1.00


81
125
2
100
1224
1.60
14
91
17
1.05


82
125
2
50
1994
1.70
32
92
15
1.01


83
125
2
25
3513
1.74
45
93
14
0.88





28Calculated as (terminal MMA units)/(terminal MMA units + terminal BA units) × 100.


29Calculated as (total MMA units)/(total MMA units + total BA units) × 100.






Examples 84–91, Control 25 and 26
Synthesis of Functional Butyl Acrylate Macromonomers
HEMA Comonomer at 80° C.—Batch Polymerization
A mixture of butyl acrylate (1.3 g; 10 mmol), 2-hydroxyethyl methacrylate, HEMA (65 mg; 0.5 mmol) (monomer ratio 20:1), n-butyl acetate (2 g), AIBN (3.74×10−4 g, 100 ppm) and isopropylcobalt(III)DMG (for concentration see Table 2.7) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 80° C. for 1 or 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.
1H-nmr (CDCl3): d 0.95, CH3; 1.40, CH2; 1.65, CH2; 1.85, backbone CH; 2.25, backbone CH2; 3.80, CH2; 4.00, CH2; 4.22, CH2; 5.50, external vinyl*; 5.80, 5.90, E&Z internal vinyl*; 6.20, external vinyl*.
(*external vinyl signals due to HEMA derived vinyl end group and internal vinyl signals due to BA derived vinyl group).







TABLE 2.7







Polymerization of butyl acrylate in presence of HEMA (20:1) and


iPrCo(III)(DMG-BF2)2 at 80° C.















Reac-









tion





%



Time
Co(III)



%
terminal


Example
(hours)
ppm
Mn
Mw
PD
Conv
alkene30

















Control 25
1
0
169,846
403,699
2.38
53
0


84
1
200
1695
3011
1.78
6
80


85
1
50
12,919
25,390
1.97
23
100


86
1
25
35,421
68,294
1.93
37
100


Control 26
2
0
58,522
200,100
3.42
98
0


87
2
400
1116
2144
1.92
13
71


88
2
200
1545
3207
2.08
19
73


89
2
100
2219
5215
2.35
24
78


90
2
50
21,852
46,133
2.11
79
a


91
2
25
38,369
95,492
2.49
97
a





a Terminal alkene protons were not visible in 1H-nmr spectrum.


30Calculated as (terminal HEMA units)/(terminal HEMA units + terminal BA units) × 100.






Examples 92–94, Control 27
Synthesis of Functional Acrylate Copolymer Macromonomers
AMS Comonomer at 80° C.—Batch Polymerization
A mixture of butyl acrylate (1.3 g; 10 mmol), 2-hydroxyethylacrylate, HEA (116 mg; 1 mmol), α-methylstyrene (26 mg; 2.2×10−4 mol) (monomer ratio 10/1/0.22), n-butyl acetate (2 g), AIBN (3.65×10−4 g, 100 ppm) and isopropylcobalt(III)DMG (for concentration see Table 2.8) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 80° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.
1H-nmr(CDCl3): d 0.90, CH3; 1.30, CH2; 1.50, CH2; 1.80, backbone CH: 2.22, backbone CH2; 3.80, CH2; 3.85, CH2; 4.98, external vinyl*; 5.20, external vinyl*; 5.80, 5.85, internal vinyl*; 6.60–7.00, internal vinyl*; 7.30, ArH.
(*external vinyl signals due to aMS derived vinyl end group and internal vinyl signals due to BA derived vinyl group).







TABLE 2.8







Copolymerization of butyl acrylate and hydroxyethyl acrylate in


presence of AMS and iPrCo(III)(DMG-BF2)2 at 80° C.





















%

%



BA/HEA/




terminal
%
terminal



AMS
Co(III)

(Mw/
%
AMS
AMS
alkene33


Example
Ration
ppm
Mn
Mn)
conv
units31
inc.32
3


















Control 27
10/1/0.22
0
66,642
1.96
30
0
9
0


92
10/1/0.22
200
1255
1.55
16
72
10
78


93
10/1/0.22
100
1712
1.76
22
19
8
100


94
10/1/0.22
50
1835
1.80
22
49
10
100





31Calculated as (terminal AMS units)/(total AMS units) × 100.


32Calculated as (total AMS units)/(total BA + total HEA units) × 100.


33Calculated as (terminal AMS units)/(terminal AMS units + terminal BA units) × 100.






Examples 95–100, Controls 28 and 29
Synthesis of Vinyl Benzoate Macromonomers
BMA Comonomer at 80° C.—Batch Polymerization
A mixture of vinyl benzoate, VB (1.3 g, 8.77 mmol), butyl methacrylate (0.125 g, 0.877 mmol) (monomer ratio: 10/1), n-butyl acetate (3 g), AIBN (4.43×10−4 g, 100 ppm) and isopropylcobalt(III)DMG (for concentration see Table 3.1) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 80° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.
1H-nmr (d6-acetone): δ 0.9, CH3; 1.35, CH2; 1.65, CH2; 1.95, CH; 2.25, backbone CH2; 2.55, allyl CH2; 4.0, OCH2; 5.2, CH; 5.45, vinyl H; 6.15, vinyl H; 6.9–7.7, ArH.







TABLE 3.1







Polymerization of vinyl benzoate in presence of BMA and


iPrCo(III)(DMG-BF2)2 at 80° C.















VB/BMA
[Co(III)]



%
% terminal


Example
ratio
ppm
{overscore (M)}n
{overscore (M)}w
PD
conv.
methylene34

















Control 28
10/1
0
67,070
106,547
1.59
12
0


 95
10/1
100
3168
4942 
1.56
5
87


 96
10/1
50
6679
12,475
1.87
7
85


 97
10/1
25
12,344
24,349
1.97
8
63


Control 29
 5/1
0
86,701
137,600
1.58
19
0


 98
 5/1
100
1720
2526
1.47
8
100


 99
 5/1
50
3464
6151
1.76
7
100


100
 5/1
25
9094
16,155
1.7
8 9
86





aCalculated as (terminal BMA units)/(terminal BMA units + terminal VB units) × 100.


34Calculated as (terminal BMA units)/(terminal BMA units + terminal VB units) × 100.






Examples 101–108, Controls 30 and 31
Synthesis of Vinyl Acetate Macromonomers Methacrylate Comonomers at 80° C.
Butyl Methacrylate Comonomers at 80° C. Batch Polymerization
VAc/BMA Macromonomer Synthesis with Monomer Ratio of 10/1
A mixture of vinyl acetate (1 g; 11.6 mmol), butyl methacrylate (0.165 g; 1.16 mmol) (monomer ratio: 10/1), n-butyl acetate (2 g), AIBN (3.17×10−4 g, 100 ppm) and isopropylcobalt(III)DMG (for concentration see Table 3.2) was placed in an ampoule and degassed by 3 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 80° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.
1H-nmr(CDCl3): d 0.95, CH3; 1.30, CH2; 1.60, CH2; 3.90, CH2; 5.40, 6.10, external vinyl CH2*.
(*external vinyl signals due to BMA derived vinyl end group).







TABLE 3.2







Polymerization of vinyl benzoate in presence of BMA and


iPrCo(III)(DMG-BF2)2 at 80° C. (VAc:BMA = 10:1)























{overscore (M)}n



Co(III)


%
% BMA
BMA
% term.
calc


Example
ppm
{overscore (M)}n
PD
conv.
terminal35
36(%)
alkene37
obs


















Control 30
0
62,363
1.78
10
0
67
0
0


101
400
499
1.40
5
33
80
100
0.9


102
200
1917
1.37
6
16
69
100
0.55


103
100
2127
2.3
7
7
72
100
1.02


104
50
4435
3.0
7
4
73
100
1.03


105
25
10,331
2.88
10
1
71
100
1.3





35Calculated as (terminal BMA units]/[total BMA units incorporated] × 100.


36Calcualted as (total BMA units)/(total VAc units + total BMA units) × 100.


37Vac derived internal alkene not detectable by 1H-nmr.






VAc/MMA Macromonomer Synthesis with Monomer Ratio of 5/1
A mixture of vinyl acetate (0.75 g; 8.77 mol), methyl methacrylate (0.175 g; 1.75 mmol) (monomer ratio: 5/1), n-butyl acetate (2 g), AIBN (2.93×10−4 g, 100 ppm) and isopropylcobalt(III)DMG (for concentration see Table 3.3) was placed in an ampoule and degassed by 3 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 80° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.
1H-nmr (d6-acetone): δ 0.6–2.1, CH3CO2 and backbone CH2; 3.60, COOCH3; 4.80–5.30, multiplet, various methine signals; 5.42, 6.10 external vinyl CH2*. (*external vinyl signal due to MMA derived vinyl end group).







TABLE 3.3







Polymerization of vinyl acetate in presence of MMA and


iPrCo(III)(DMG-BF2)2 at 80° C. (VAc:MMA = 5:1)























{overscore (M)}n



Co(III)


%
% MMA
% MMA
% term.
calc


Example
ppm
{overscore (M)}n
PD
conv
terminal38
inc.39
alkene40
obs


















Control 31
0
40,448
1.87
8
0
87
 0
—


106
100
11,806
2.26
5
0.9
87
100
1.0 


107
50
12,487
2.38
8
0.8
88
100
1.06


108
25
30,782
1.92
8
041
87
 041 
—





38Calculated as (terminal MMA units)/(total MMA units incorporated) × 100.


39Calculated as (total MMA units)/(total Vac units + total MMA units) × 100.


40Calculated as (terminl MMA units)/terminal Vac units + terminal MMA units) × 100. Vac derived internal alkene not detectable by 1H-nmr.


41Terminal vinyl signals could not be detected by 1H-nmr.






Examples 109–116, Controls 32 and 33
Synthesis of Vinyl Acetate Macromonomers
Isopropenyl Acetate, iPA Comonomer at 125° C.—Batch Polymerization
A mixture of vinyl acetate (1.0 g; 11.6 mmol), isopropenyl acetate (23 mg; 0.232 mmol) (monomer ratio: 50/1), n-butyl acetate (2 g), VR®-110 (3.4×10−4 g, 100 ppm) and isopropylcobalt(III)DMG (for concentration see Table 3.4) was placed in an ampoule and degassed by 3 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 125° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.
1H-nmr (CDCl3): d 1.2–2.1, CH2+CH3CO; 4.7–5.2, multiplet, various backbone methine.







TABLE 3.4







Polymerization of vinyl acetate in presence of iPA and


iPrCo(III)(DMG-BF2)2 at 125° C.





















%



Vac/iPA
Co(III)



%
term.


Example
ratio
ppm
Mn
Mw
PD
conv
iPA

















Control 32
 5/1
0
11,964
21,818
1.82
47
0


109
 5/1
200
502
983
1.40
2
b


110
 5/1
100
696
1124
1.61
2
b


111
 5/1
50
1240
2278
1.84
2
b


112
 5/1
25
z4781
11,189
2.34
9
b


Control 33
50/1
0
15,271
29,423
1.93
90
0


113
50/1
200
772
1329
1.72
2
a


114
50/1
100
1295
2517
1.94
3
a


115
50/1
50
2353
6484
2.76
5
b


116
50/1
25
13,518
23,737
1.76
16
b





a end group signals observed but reliable quantitation not possible.


b no end group signals detected.






Examples 117–128, Controls 34 to 36
Synthesis of Vinyl Acetate Macromonomers
Isopropenyl Chloride Comonomer at 125° C.—Batch Polymerization VAc/iPrCl Macromonomer Formation at 125° C. with VR®-110 and iPrCo(III)(DMG-BF2)2 
A mixture of vinyl acetate (1 g, 11.6 mmol), isopropenyl chloride (0.18 g, 2.32 mmol) (monomer ratio: 5/1), n-butyl acetate (2 g), VR®-110 (3.18×10−4 g, 100 ppm) and iPrCo(III)(DMG-BF2)2 (for concentration see table 3.5) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 125° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.







TABLE 3.5







Polymerization of vinyl acetate in presence of iPCI and


iPrCo(III)(DMG-BF2)2 at 125° C.














Vac/
Co(III)



%


Example
iPrCl
ppm
Mn
Mw
PD
conv
















Control 34
 5/1
0
3969
7475
1.88
3


117
 5/1
200
350
434
1.24
1


118
 5/1
100
552
1323
2.40
<1


119
 5/1
50
1355
3833
2.82
1


120
 5/1
25
1791
5143
2.87
<1


Control 35
50/1
0
15,712
27,346
1.74
14


121
50/1
200
717
973
1.35
<1


122
50/1
100
1230
1843
1.49
<1


123
50/1
50
2692
4594
1.71
1


124
50/1
25
12,243
21,771
1.78
8









VAc/iPrCl Macromonomer Formation at 125° C. with VR®-110 and MRCo(III)(DEG-BF2)2 
A mixture of vinyl acetate (1 g, 11.6 mmol), isopropenyl chloride (18 mg, 0.232 mmol) (monomer ratio: 50/1), n-butyl acetate (2 g), VR®-110 (3.15×10−4 g, 100 ppm) and MeCo(III)(DEG-BF2)2 (for concentration see table 3.6) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 125® for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by GPC.







TABLE 3.6







Polymerization of vinyl acetate in presence of


iPCl and MeCo(III)(DEG-BF2)2 at 125° C.














VAc/








iPrCl
Co(III)


Example
ratio
ppm
Mn
Mw
PD
% conv
















Control 36
50/1
0
13,984
24,811
1.77
46


125
50/1
200
935
1502
1.60
<1


126
50/1
100
1627
3001
1.84
1


127
50/1
50
10,605
19,522
1.84
6


128
50/1
25
12,740
22,831
1.79
10









Examples 129–132, Control 37
Synthesis of Functional Styrene Macromonomer
TMI®—Cytec Incorporated Comonomer
Feed Polymerization
A mixture of styrene (1 g, 9.6 mmol), TMI® (0.2 g, 0.96 mmol) (monomer ratio: 10/1), n-butyl acetate (2 g), VR®-110 (3.2×10−4 g, 100 ppm) and isopropylcobalt(III)DMG (at 0, 25, 50, 100 and 200 ppm) was placed in an ampoule and degassed by 4 freeze-thaw cycles. The ampoule was sealed and the mixture heated at 125° C. for 2 hours. The ampoule was cooled, opened and the reaction mixture reduced in vacuo to a residue which was analysed by 1H-nmr and GPC.
1H-nmr(d6-acetone): δ 4.9, external vinyl*; 5.20, external vinyl*; 6.0–6.2, internal vinyl*; 6.6–7.4, ArH.
(*external vinyl signals due to TMI® derived vinyl end group and internal vinyl signals due to Sty derived vinyl end group).







TABLE 4.1







Polymerization of styrene in presence of TMI ® and


iPrCo(III)(DMG-BF2)2 at 125° C.














Sty/




% terminal



TMI ®
Co(III)



TMI ®


Example
ratio
ppm
Mn
Mw
PD
units42
















Control 37
10/1
0
85,912
133,091
1.67
0


129
10/1
200
475
602
1.27
47


130
10/1
100
640
903
1.41
53


131
10/1
50
887
1373
1.55
60


132
10/1
25
1274
2155
1.73
75





42Calculated as (terminal TMI units)(terminal TMI units + terminal Sty units).






Example 133
A mixture of 2.5 mL MA, 0.5 mL 2-chloro-2-propenol, 14 mg TAPCo, 20 mg VAZO-88 and 5 mL chloroform was degassed by three freeze-pump-thaw cycles. The reaction mixture was kept at 90° C. until 10–15% conversion was attained. GPC analysis showed Mn≈2150, PD=2.0.
Example 134
A mixture of 2.5 mL MA, 0.5 mL ethyl 2-hydroxymethylacrylate, 14 mg TAPCo, 20 mg VAZO-88 and 5 mL chloroform was degassed by three freeze-pump-thaw cycles. The reaction mixture was kept at 90° C. until 10–15% conversion was attained. GPC analysis showed Mn≈1600, PD=3.2.
Example 135
A mixture of 2.5 mL MA, 0.5 mL styrene, 14 mg TAPCo, 20 mg VAZO-88 and 5 mL chloroform was degassed by three freeze-pump-thaw cycles. The reaction mixture was kept at 90° C. until 10–15% conversion was attained. GPC analysis showed Mn≈700, PD=2.4.
Example 136
A mixture of 2.5 mL MA, 0.5 mL 2-hydroxyethyl methacrylate, 14 mg TAPCo, 20 mg VAZO-88 and 5 mL chloroform was degassed by three freeze-pump-thaw cycles. The reaction mixture was kept at 90° C. until 10–15% conversion was attained. GPC analysis showed Mn≈2150, PD=2.0.
Control 38
A mixture of 2.5 mL MA, 14 mg TAPCo, 20 mg VAZO®-88 and 5 mL chloroform was degassed by three freeze-pump-thaw cycles. The reaction mixture was kept at 90° C. until 10–15% conversion was attained. GPC analysis showns Mn≈21,700, PD=2.4.
Example 137
High Conversion Copolymerization of BA and MMA to Branched and Hyperbranched Polymers
The reincorporation of initially-formed macromonomers back into the growing polymer is demonstrated.
Identical solutions of 32 mg of VAZO®-88 and 4 mg Co(II)(DPG-BF2)2 in 7.7 mL of butyl acrylate (BA), 1.5 mL MMA and 8 mL of 1,2-dichloroethane were degassed and kept in a 90° C. oil bath. The samples were removed from the temperature bath at various times shown in Table 5.1. Then each reaction mixture was chilled and evaporated in high vacuum till constant weight. The results, shown in Table 5.1, indicates that MW increases sharply at the end of the polymerization process. Because most of the monomer had been consumed before the increase in molecular weight, the only way that it could occur is through reincorporation of the macromonomers formed at the beginning of the reaction. GPC and K+IDS data are consistent.









TABLE 5.1





Conversion
Mn
Mn/Mw

















12%
540
2.08


20%
640
2.08


55%
890
2.06


93%
2270
2.84









The catalyst remained active during the course of the polymerization. Sudden inactivation of the catalyst at conversion >60% cannot account for an increase of the Mn from 890 at 55% conversion to 2270 at 93% conversion. Less than doubling of the conversion (93% vs 55%) cannot provide a 2.6 fold increase of the Mn (2270 vs 890) maintaining a unimodal distribution.
The linear macromonomers formed at 55% conversion were incorporated into the polymer at higher conversions. The incorporation of macromonomer into growing polymer chains provides branched polymer. With continuous termination of polymeric radicals by the cobalt catalyst, such an incorporation leads to polymer with a structure containing “branches-on-branches”—in the extreme, it is hyperbranched.
Confirmation of the macromonomer reincorporation into the polymer back-bone was provided by MALDI mass spectroscopy. As seen on the MALDI spectra, at conversions <50% the polymer contains from 1 to 5 MMA units per chain. For Mn≈900, it means that the polymer is enriched with MMA vs composition of the initial monomer solution. As a result, the concentration of unreacted MMA monomer in the solution decreases faster than that of BA. At 55% conversion, more than 70% of the original MMA is consumed.
Fewer MMA units are available to be incorporated into the high molecular weight polymer formed at conversions >60% than at lower conversions if polymer that forms at high conversion does not incorporate previously formed rnacromonomer. Incorporation of the previously-formed macromonomer would provide MMA to the high molecular weight polymer. The MALDI spectrum of the polymer at 93% conversion demonstrated this clearly. The MALDI spectrum of the polymer at 93% conversion becomes unresolved at masses >2500 due to the high levels of MMA incorporation.
Example 138
A reaction mixture containing 4 mg of the CTC-catalyst (COBF), 32 mg of VAZO®-88, 2 ml of butyl acrylate, 6 ml MMA-trimer, 0.2 ml of methyl methacrylate and 4 ml of 1,2-dichloroethane was degassed by three freeze-pump-thaw cycles and put into an oil bath at 90° C. Samples of the reaction mixture were taken after 1.5 hours, 3 hours, 7 hours and 22 hours. Initial GPC analysis shows that molecular weight of the polymeric product increases with time. Comparision of GPC data with that of KIDS and MALDI shows that in the first case the average measured MW are lower than expected in case of higher conversion samples. The first samples had readily observable quantities of vinylene protons (1H NMR spectra), indicating the formation of methacrylate-terminated polymer at the beginning of the CTC process. All of these observations are consistent with the proposed scheme.

## Claims

1. A polymer having the formula:




where Y≠R′ and n≧1; in which
Y is selected from the group consisting of OR, O2CR, halogen, CO2H, COR, CO2R, CN, CONH2, CONHR and CONR2; wherein
R is selected from the group consisting of substituted and unsubstituted alkyl, substituted and unsubstituted aryl, substituted and unsubstituted heteroaryl, substituted and unsubstituted aralkyl, substituted and unsubstituted alkaryl, and substituted and unsubstituted organosilyl, the substituents being the same or different and selected from the group consisting of carboxylic acid, carboxylic ester, epoxy, hydroxyl, alkoxy, primary amino, secondary amino, tertiary amino, isocyanato, sulfonic acid and halogen, and the number of carbons in said alkyl groups is from 1 to 12; and
R′ is selected from the aromatic group consisting of substituted and unsubstituted aryl, substituted and unsubstituted heteroaryl, the substituents being the same or different and selected from the group consisting of carboxylic acid, carboxylic ester, epoxy, hydroxyl, alkoxy, primary amino, secondary amino, tertiary amino, isocyanato, sulfonic acid, substituted and unsubstituted alkyl, substituted and unsubstituted aryl, substituted and unsubstituted olefin and halogen.