Ethyl vinyl ether, copolymerization

This article reports on the synthesis of photosensitive polymers with pendant cinnamic ester moieties and suitable photosensitizer groups by cationic copolymerizations of 2-(cinnamoyloxy)ethyl vinyl ether (CEVE) (12) with other vinyl ethers containing photosensitizer groups, and by cationic polymerization of 2-chloroethyl vinyl ether (CVE) followed by substitution reactions of the resulting poly (2-chloroethyl vinyl ether) (PCVE) with salts of photosensitizer compounds and potassium cinnamate using a phase transfer catalyst in an aprotic polar solvent. The photochemical reactivity of the obtained polymers was also investigated. 

An investigation into the initiation mechanism of copolymerization of ethyl vinyl ether and acrylonitrile by /-butoxyl radicals lias shown that the reaction between the two monomers competes successfully with radical trapping by the nitroxide radical trap (5).37 The /-butoxyl radicals react 3-6 times faster with ethyl vinyl ether than acrylonitrile the authors proposed that this is due to selective interaction of one monomer with the radical species rather than a solvent polarity effect. 

The polarity of any species is independent of whether it is in monomer or radical form for the free radical is a neutral entity. Thus assuming that the above types of polarization are also possible with radicals, one can understand that a chain end at which there happens to be a structural unit with an electron-withdrawing substituent, prefers a monomer with an electron-donating substituent and vice versa. Such consideration of polarity explains that, for example, acrylonitrile forms statistical copolymers with methyl acrylate (rir2 = 1.26), while copolymerization of acrylonitrile with ethyl vinyl ethers leads to alternating structures (r r2 == 0.04). 

In the copolymerization of BCMO with a-methylstyrene, /(-methylstyrene, 2-chloro-ethyl vinyl ether and isobutylene, the latter three comonomers yield a benzene-soluble fraction that contains Cl55). Since PolyBCMO is insoluble in benzene, this result may indicate the formation of some products containing vinyl monomers and BCMO. Information about the products is rather scarce, and it is quite likely that copolymers did not form and that the Cl in the soluble fractions was due to secondary alkylation processes. 

TADs can be used in polymer chemistry in several different ways. Simple TADs, e.g., PTAD, copolymerize with other components. Ethyl vinyl ether... 

The ROMP of cyclooctene-5-methacrylate and its copolymerization with cyclooctadiene is catalyzed by Ru(=CHCH=CPh2)(Cl)2(PCy3)2 in the presence of p-methoxyphenol as radical inhibitor. The double bonds in the methacrylate groups are inert towards metathesis. After chain transfer with ethyl vinyl ether to release the polymer from the ruthenium centre, it can be cross-linked by radical polymerization through the methacrylate side-chains (Maughon 1995). 

Zeegers and Butler [43] studied the kinetics of the AIBN-initiated copolymerization of divinyl ether and ethyl vinyl ether with maleic anhydride in seven different solvents. The yield at 100% conversion as a function of the feed composition when the total monomer concentration was kept constant gave confirmation of the composition of these copolymers Divinyl ether maleic anhydride=l 2 and ethyl vinyl ether maleic anhydride = 1 1. The study of the initial rate as a function of the feed composition made it possible to determine the relative values of the different propagation rate constants consistent with a mechanism by successive and selective additions. In the ethyl vinyl ether-maleic anhydride system, addition of ethyl vinyl ether is slower than addition of maleic anhydride in the divinyl ether-maleic anhydride system, the addition of divinyl ether is slower than addition of the first molecule, while addition of the second maleic anhydride molecule is slower than the first one. The study of... 

Copolymerization of Maleic Anhydride with Ethyl Vinyl Ether. 249... 

Fujimori showed that the above concept also holds for ethyl vinyl ether (EVE), 2,3-dihydropyran (DHP), and divinyl ether (DVE). The e values of DHP, EVE, and DVE (Table 10.14), respectively, become negatively larger as the equilibrium constants of their CTC with MA increase in the same order ii (DHP-MA) - 0.11 jK (EVE-MA) = 0.15, and i (DVE-MA) = 0.18 liter mole Under the same conditions, the conversion for the copolymerization of DHP with MA after 10 h was comparable to that of the copolymerization of EVE with MA after only 100 min. It is hard to conceive how such a small difference between the K values of DHP and EVE with MA could bring about such a great difference between the copolymerization rates of the two pairs. Zeegers and Butler claimed that the polymerization kinetics of DVE with MA could be explained without the intervention of a CTC, but charge-transfer complexes may participate in competing reactions. 

Figure 3.10 (a) Direct copolymerization of H bonds via ROMP and the alternative reaction pathway to yield a similar polymer, (b) End-group-modified telechelic polynorbomenes via quench with functionalized ethyl-vinyl ethers. 

Accordingly, N-vinylcarbcizole, ethyl vinyl ether, p-methoxystyrene (pMeOSt), and a-methylstyrene (aMeSt) are 17 400, 1380, 339, and 37 times more reactive than styrene (St). Due to this very large difference in cationic reactivity, different initiating systems bring about optimum polymerization for different monomers. This also explains why cationic statistical copolymerizations are less useful than the radical counterpart. 

The cationic copolymerizations of PNVE with 50 mol% of other vinyl ethers such as (2-phenoi )ethyl vinyl ether (PEVE), 2-isobutyl vinyl ether (IBVE), and CEVE were performed in dich loromethane using 3 mol% of BF3 CXEt)2 as the catalyst at -40 °C. 

Acrylate copolymers produced by emulrion polymerization are being used as elastomers which, after vulcanization, have a combination of heat resistance and oil resistance useful in specialty applications such as gai ts for automatic transmissions in automotive engines. Two t3q>es of copolymers are being used. In one, ethyl acrylate is copolymerized with about 5 per cent of a chloro-containing monomer such as chloroethyl vinyl ether in the other, either ethyl acrylate or butyl acrylate is copolymerized with about 5-15 per cent of acrylonitrile., ... 

Attempts have been made over time to improve the physical properties of novolacs. The use of phenol formaldehyde resins prepared in alkaline medium in photoresist compositions is mentioned in a Kalle Co. AG patent. The use of polyvinyl ethers in combination with novolacs to impart stickiness and plasticization action to the latter was patented by Christensen. Steinhoff, Isaacson, and Roelants of the Shipley Company mention the use of vinyl ethers in a patent on roller coating. Lower alkyl polyvinyl ethers, such as methyl, ethyl, butyl, and isobutyl, are added to novolac resins to improve coating flexibility and adhesion to metal surfaces as well as to improve resistance to mildly alkaline solutions. The use of styrene, methyl styrene, and styrene-maleic anhydride copolymers in combination with novolac was mentioned in several patents of both Shipley and Kalle Co. AG. When novolac is copolymerized with maleic anhydride, a resin that is readily soluble in alkaline solutions is obtained. ... 

Alkyl vinyl ethers can also be copolymerized cationically with such monomers as styrene using SnCl4/AlCl3 catalyst and in ethyl chloride solution [25-27]. 

In addition to the terpolymers previously mentioned that contain acrylates,the methyl acrylate-MA and methyl methacrylate-MA monomer pairs have been copolymerized with each other, " " acrylic acid, 2-ethylhexyl acrylate, " ethyl acrylate, " glycidyl methacrylate, " acrylonitrile, vinylidene chloride, and isobutyl vinyl ether. 

Baldwin studied the kinetics of the copolymerization of isobutyl vinyl ether and MA in ethyl acetate at 60°C. Ethyl acetate was used because it is a good solvent for both monomers, copolymer, and initiators. The maximum rate was observed at a vinyl isobutyl ether-MA mole ratio of 4 1 and very low rates were obtained in the presence of large excesses of anhydride. For a 5.5 1 mole ratio, the rate was linear until the anhydride was consumed and zero order with respect to the vinyl ether. All copolymers were equimolar in composition. From light-scattering studies on a series of copolymers in tetrahy-... 

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