Copolymerization with styrenic monomers

Polyaddition reactions based on isocyanate-terminated poly(ethylene glycol)s and subsequent block copolymerization with styrene monomer were utilized for the impregnation of wood [54]. Hazer [55] prepared block copolymers containing poly(ethylene adipate) and po-ly(peroxy carbamate) by an addition of the respective isocyanate-terminated prepolymers to polyazoesters. By both bulk and solution polymerization and subsequent thermal polymerization in the presence of a vinyl monomer, multiblock copolymers could be formed. 

Polyester polymer units react (copolymerize) with styrene monomer in presence of catalyst and/or heat to yield styrene-polyester copolymer resin or, more simply, a cured polyester, I Asterisk indicates points capable of further cross-linking, I... 

Styrene and methyl methacylate have been used as comonomers in many investigations of copolymerization. Use the following listj of ri values for each of these copolymerizing with the monomers listed below to rank the latter with respect to reactivity ... 

On the organic side of the interface, chemical bonds are formed between the organofunctional R group of the silane and the reactive species in the polymer matrix. For example, a methacrylate- or styryl-functional silane reacts with polyesters copolymerized with styrene or similar monomers, while amino- or chloroalkyl-functional silanes are unsuitable in this particular case. Polybutadiene... 

Kondo maintained his interest in this area, and with his collaborators [62] he recently made detailed investigations on the polymerization and preparation of methyl-4-vinylphenyl-sulfonium bis-(methoxycarbonyl) meth-ylide (Scheme 27) as a new kind of stable vinyl monomer containing the sulfonium ylide structure. It was prepared by heating a solution of 4-methylthiostyrene, dimethyl-diazomalonate, and /-butyl catechol in chlorobenzene at 90°C for 10 h in the presence of anhydride cupric sulfate, and Scheme 27 was polymerized by using a, a -azobisi-sobutyronitrile (AIBN) as the initiator and dimethylsulf-oxide as the solvent at 60°C. The structure of the polymer was confirmed by IR and NMR spectra and elemental analysis. In addition, this monomeric ylide was copolymerized with vinyl monomers such as methyl methacrylate (MMA) and styrene. 

Butadiene is by far the most important monomer for synthetic rubber production. It can be polymerized to polybutadiene or copolymerized with styrene to styrene-butadiene rubber (SBR). Butadiene is an important intermediate for the synthesis of many chemicals such as hexa-methylenediamine and adipic acid. Both are monomers for producing nylon. Chloroprene is another butadiene derivative for the synthesis of neoprene rubber. 

Polystyrene (PS) is the fourth big-volume thermoplastic. Styrene can be polymerized alone or copolymerized with other monomers. It can be polymerized by free radical initiators or using coordination catalysts. Recent work using group 4 metallocene combined with methylalumi-noxane produce stereoregular polymer. When homogeneous titanium catalyst is used, the polymer was predominantly syndiotactic. The heterogeneous titanium catalyst gave predominantly the isotactic. Copolymers with butadiene in a ratio of approximately 1 3 produces SBR, the most important synthetic rubber. 

Ring-opening polymerization of 2-methylene-l,3-dioxepane (Fig. 6) represents the single example of a free radical polymerization route to PCL (51). Initiation with AIBN at SO C afforded PCL with a of 42,000 in 59% yield. While this monomer is not commercially available, the advantage of this method is that it may be used to obtain otherwise inaccessible copolymers. As an example, copolymerization with vinyl monomers has afforded copolymers of e-caprolactone with styrene, 4-vinylanisole, methyl methacrylate, and vinyl acetate. 

Isopropenylferrocene does not homopolymerize under free radical conditions using AIBN as an initiator, but it does copolymerize with styrene.Preliminary results indicate that the IDM monomer also copolymerizes with styrene using AIBN. In benzene solvent at 50°C in 24 h, a 10.6% yield of copolymer (IR vc=0 2020, 1945 cm , vN=0 1675 cm-- -, V q 1601 cm-- -, v 3020 cm-- -) resulted having an M f 5700 and containing 6.8% of IDM as determined by elemental analysis. The initial monomer mixture contained 17% of IDM. 

To improve the polymerizability of organotin monomers, a convenient method for the production of trialkylstannyl-1,3-alkadienes has been developed 54 57) and their copolymerization with styrene and methyl methacrylate studied 58 59). 

The major four-carbon feedstock molecules are 1,3-butadiene and isobutylene, both involved in the synthesis of many monomers and intermediates. Butadiene is copolymerized with styrene to form SBR and with acrylonitrile to form ABS rubbers. 

Ferrocenylmethyl acrylate (FMA) and 2-ferrocenylethyl acrylate (FEA) have been synthesized and copolymerized with styrene, methyl acrylate, and vinyl acetate [C. U. Pittman, Jr., Macrmolecules, 4, 298 (1971)]. The following monomer reactivity ratios were found ... 

The grafting-through method has also been studied for ATRP. Vinyl chloroacetate is used as the initiator in ATRP of a monomer such as styrene to produce a macromonomer. Vinyl chloroacetate does not significantly copolymerize with styrene, and the result is a polystyrene vinyl macromonomer, which is then polymerized to a brush polymer [Davis and Matyjaszewski, 2002],... 

On this basis, values of Q and e can be calculated for each monomer, so long as two arbitrary reference values are assumed. For this purpose Price took the values for styrene as Q = 1.0 and e = -0.8. Q and e values can then be obtained for all monomers that are copolymerizable with styrene. These monomers in their turn can serve as reference compounds for further determinations with other monomers that do not copolymerize with styrene. One of the main advantages of the so-called Q,e scheme is that the data can be presented in the form of a diagram instead of very complex tables of reactivity ratios. 

COPOLYMERIZATION WITH PARTICIPATION OF MULTIMONOMERS Synthesis of various multimonomers and their copolymerization with styrene, acrylonitrile or acrylic acid was described in a set of papers. Most of the early work on the copolymerization of multimonomers with vinyl monomers employed p-cresyl formaldehyde resins, esterified by methacryloyl chloride or acryloyl chloride, as one of the comonomers, and a simple vinyl monomer such as styrene or acrylonitrile as the other monomer. 

Catalysts synthesized from crown ether monomers 61 and 62 by copolymerization with styrene and either p-divinylbenzene or p,p -divinylbiphenyl (63) are listed in Table 14 along with their relative activities for solid/solid/liquid reactions of potassium acetate with benzyl chloride (Eq. (13)) and potassium cyanide with 1,4-dichlorobutane (Eq. (14)) in acetonitrile 183). 

Thermally, the monomers 4-6 and 9 are considerably more stable than the monomers 1-3, 7 and 8 36,4S 5Z). Thus, for these monomers, not only emulsion polymerization, but also all other polymerization techniques, including those requiring higher temperatures, can be applied without the complicating effect of the thermolysis of the azo function occurring. The monomers 4,6 and 9 have been copolymerized with styrene 36). In contrast to 1-3, 0.5 mol % of 4, 6 and 9 have little effect on the overall rate of the polymerization (Table 3.9 Fig. 3.5). 

These two initiating sites might be considered to compete for monomer, but it appears that initiation is at the anionic site. In this study sodium benzophenone was used as initiator in tetrahydrofuran at 0°. Anionic polymerization was suggested by infrared evidence, by the rapid polymerization and by obtaining nearly pure polyacrylonitrile in attempted copolymerization with styrene. Inoue, Tsuruta and Furukawa (81) show that initiation is sensitive to specific reaction conditions. In their experiments sodium and potassium benzophenone gave polymer, but the lithium compound was ineffective. 

The latter technique is more rapid than the former (27, 31). In 1930 Wagner-Jauregg showed that alternating copolymers are obtained when maleic anhydride is copolymerized with vinyl monomers (34). This is true for copolymerization in good solvents, but when the molar ratio of styrene to maleic anhydride is greater than 1, styrene may add to the alternating copolymer in poor solvents to produce block copolymers. 

Acrylonitrile resembles VC, a carcinogen, in structure. It is a flammable, explosive liquid (b.p. 77 C, V.P. 80 mm at 20°C). AN is a component of acrylic and modacrylic fibers produced by copolymerization with other monomers, e.g., with methyl acrylate, Me-methacrylate, vinyl acetate, VC and VDC. Other major uses of AN include copolymerizations with butadiene and styrene to produce ABS polymers, and with styrene to yield SAN resins which are used in the manufacture of plastics. Nitrile elastomers and latexes are also made with AN, as are a number of other chemicals, e.g. acrylamide and adiponitrile. Acrylonitrile is also used as a fumigant. 

Our kinetic work (10) showed that the small molecule radical produced by chain transfer with monomer had to be a stable radical. This was confirmed in the present paper by analysis of the isotope effect on the bulk polymerization rates. The isotope effect on molecular weights and rates unequivocally showed that almost 100% of the chain transfer involved the vinyl hydrogen. There is some evidence in the literature to support the idea of a stable vinyl radical. Phenyl acetylene acts as a retarder when copolymerized with styrene or methyl methacrylate (25). Thus the phenyl vinyl radical is very stable compared to the growing styryl or methacrylyl radical. 

Reaction medium. When lignosulfonate was subjected to graft copolymerization with vinyl monomers, the extent of copolymerization due to the effect of medium varied from one monomer to another. In a LS-styrene system (16), it was found that methanol was a better medium than water under certain given conditions while in a LS-acrylonitrile system (17),the contrary was true, i.e., water better than methanol. This contradiction was thought due to the fact that styrene has electropositive (i.e., electronreleasing) substituent while acrylonitrile has electronegative (i.e., electron-attracting) substituent. In the present study,... 

Styrene can be copolymerized with many monomers. The following monomers can be used along with styrene in the manufacture of food contact materials a-methylsty-rcne, vinyltoluene, divinylbenzene, acrylonitrile, ethyleneoxide, butadiene, fumaric and maleic acid esters of the mono functional saturated aliphatic alcohols C1-C8, acrylic acid ester and methacrylic acid, maleic acid anhydride, methylacrylamide-methylol ether, vinylmethyl ether, vinylisobutyl ether. Styrene and/or a-methylstyrene and/or vinyltoluene should be the main mixture component in every case. 

It is well known that primary amines are efficient initiators for the polymerization of Leuch s anhydrides (oxazolidinediones) and that initiation proceeds by the addition of the amine to the monomer. This pathway has been utilized recently to synthesize polypeptide macromonomers bearing a terminal p-vinylbenzyl group 88). Copolymerization of these macromonomers with a vinylic or acrylic comonomer yields graft copolymers with polypeptide grafts. Alternately, the monomer adduct (IV) was copolymerized with styrene, and the primary amine functions of this polymer were used to initiate the polymerization of an oxazolidinedione whereby polypeptide grafts are formed 89). Such graft copolymers may be of interest for biomedical applications. 

Pure acrylonitrile may polymerize at room temperature to polyacrylonitrile (PAN), a compound that, unlike polyamides and polyesters, does not melt at elevated temperatures but only softens and finally discolors and decomposes. Nor is it soluble in inexpensive low-boiling organic solvents. Because fibers made from it resist the dyeing operations commonly used in the textile industry, the usual practice is to modify it by copolymerization with other monomers, for example, vinyl acetate, styrene, acrylic esters, acrylamide, or vinyl pyridine in amounts up to 15 percent of the total weight (beyond which the final product may not be termed an acrylic fiber). The choice of modifier depends on the characteristics that a given manufacturer considers important in a fiber, the availability and cost of the raw materials in the manufacturer s particular area of production, and the patent situation. 

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