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Copolymerization of vinyl monomers with

Grafting can also be obtained by addition copolymerization of vinyl monomers with unsaturated polymers. The unsaturation may be located either in the side groups or in the backbone. [Pg.185]

The low effect of the structure of oligomer alkyl radicals on the rate constant of their reaction with oxygen also follows from the review article on the copolymerization of vinyl monomers with oxygen in the liquid phase. [Pg.203]

In contrast to the above situations, parylene polymer deposition has very poor adhesion to a smooth surface substrate but can penetrate deep into small cavities. para-Xylylene prefers to react with another para-xylylene or its derivatives. Although it has the feature of difunctional free radical, it is rather stable and does not initiate polymerization of other monomers for conventional free radical polymerization. In spite of numerous attempts, the polymerization of various vinyl monomers initiated by para-xylylene or copolymerization of vinyl monomers with /7ura-xylylene has been elusive. [Pg.62]

Some typical values of reactivity ratios for monomers that will copolymerize via a free-radical route are shown in Table 1.15 (Tirrell, 1989, Allcock and Lampe, 1981). These have been selected in order to span the range of values shown in the preceding tables. It may be noted that the copolymerization of vinyl monomers with maleic anhydride will invariably lead to alternating copolymers since rj 2 0. The mechanism of alternating... [Pg.90]

R. A. Patsiga, Copolymerization of vinyl monomers with ring compounds, J. Macromol. Sci. C... [Pg.313]

According to this equation, the dielectric constant of the solvent is expected to influence the copolymerization. In actual fact, such an effect is very seldom observed. An exception is found, for example, in the copolymerization of vinyl monomers with oxygen to polyperoxides. Thus, equation (22-46) is not applicable in the general case, probably because the partial charges are not localized at all. In addition, the polarity effects are small in comparison to the resonance effects (see Section 22.4.1). [Pg.785]

Copolymerization of Vinyl Monomer with o ,i3-Substituted Olefin... [Pg.163]

In order to increase the solubiUty parameter of CPD-based resins, vinyl aromatic compounds, as well as other polar monomers, have been copolymerized with CPD. Indene and styrene are two common aromatic streams used to modify cyclodiene-based resins. They may be used as pure monomers or contained in aromatic steam cracked petroleum fractions. Addition of indene at the expense of DCPD in a thermal polymerization has been found to lower the yield and softening point of the resin (55). CompatibiUty of a resin with ethylene—vinyl acetate (EVA) copolymers, which are used in hot melt adhesive appHcations, may be improved by the copolymerization of aromatic monomers with CPD. As with other thermally polymerized CPD-based resins, aromatic modified thermal resins may be hydrogenated. [Pg.355]

The reactions of alkyl hydroperoxides with ferrous ion (eq. 11) generate alkoxy radicals. These free-radical initiator systems are used industrially for the emulsion polymerization and copolymerization of vinyl monomers, eg, butadiene—styrene. The use of hydroperoxides in the presence of transition-metal ions to synthesize a large variety of products has been reviewed (48,51). [Pg.104]

Random copolymers of vinyl chloride and other monomers are important commercially. Most of these materials are produced by suspension or emulsion polymerization using free-radical initiators. Important producers for vinyl chloride—vinyUdene chloride copolymers include Borden, Inc. and Dow. These copolymers are used in specialized coatings appHcations because of their enhanced solubiUty and as extender resins in plastisols where rapid fusion is required (72). Another important class of materials are the vinyl chloride—vinyl acetate copolymers. Principal producers include Borden Chemicals Plastics, B. F. Goodrich Chemical, and Union Carbide. The copolymerization of vinyl chloride with vinyl acetate yields a material with improved processabihty compared with vinyl chloride homopolymer. However, the physical and chemical properties of the copolymers are different from those of the homopolymer PVC. Generally, as the vinyl acetate content increases, the resin solubiUty in ketone and ester solvents and its susceptibiUty to chemical attack increase, the resin viscosity and heat distortion temperature decrease, and the tensile strength and flexibiUty increase slightly. [Pg.185]

Recently, Li et al. [30], Yu et al. [31] reinvestigated the mechanism of graft copolymerization of vinyl monomers onto carbohydrates such as starch and cellulose initiated by the Ce(IV) ion with some new results as mentioned in Section II. Furthermore, they investigated the mechanism of model graft copolymerization of vinyl monomers onto chitosan [51]. They chose the compounds containing adjacent hydroxyl-amine structures, such as D-glucosamine, /mn5-2-amino-cyclohexanol, 2-... [Pg.551]

Therefore, the graft copolymerization of vinyl monomers onto macromolecules having active an pendant group can be achieved either by redox initiation with a Ce(IV) ion or by photo-induced charge-transfer initiation with BP, depending on the structure of the active groups. [Pg.552]

Up to this point we ve discussed only homopolymers—polymers that are made up of identical repeating units, in practice, however, copolymers are more important commercially. Copolymers are obtained when two or more different monomers are allowed to polymerize together. For example, copolymerization of vinyl chloride with vinylidene chloride (1,1-dichloroethylene) in a 1 4 ratio leads to the polymer Saran. [Pg.1210]

Free-radical copolymerization of vinyl acetate with various vinyl siloxane monomers was described 345). Reactions were conducted in benzene at 60 °C using AIBN as the initiator. Reactivity ratios were determined. Selective hydrolysis of the vinyl acetate units in the copolymer backbone was achieved using an aqueous sodium hy-droxide/THF mixture. The siloxane content and degree of hydrolysis were determined by H-NMR. [Pg.57]

Our research in this field is mainly carried out on a) synthesis and conversion of oligoorganoepoxystannanes b) free-radical copolymerization of organotin monomers with various vinyl monomers and c) cross-linking of organotin macromolecules and development of protective polymeric coatings with specific properties on their basis. [Pg.111]

According to this scheme the fundamental difference in the mechanism of free-radical copolymerization of MA with TASM and of MA with alkyl acrylates is due to the fact that in the former copolymerization intermolecular coordination is involved. This coordination is similar to the effect of various complexing agents (ZnCl2, SnCft and A1C13) on free-radical homo- and copolymerization of vinyl monomers. This effect seems to favor the appearance of isotactic configurations along the main chain. [Pg.123]

P, N, O, S, or C based, which favor covalent bonding and stabilize low oxidation states) due to the metals higher electronegativity and lower oxidation states [24], In recent years, late transition metal catalysts [25-29] have attracted attention not only for the polymerization of a-olefins, but more importantly for the copolymerization of hydrocarbon monomers with readily available polar monomers such as acrylates, vinyl ethers, and vinyl acetate [27 and references therein]. [Pg.163]

The polymerization of alkyl vinyl ethers is of some commercial importance. The homopolymers, which can be obtained only by cationic polymerization, are useful as plasticizers of other polymers, adhesives, and coatings. (The copolymerization of vinyl ethers with acrylates, vinyl acetate, maleic anhydride, and other monomers is achieved by radical polymerization but not the homopolymerizations of alkyl vinyl ethers.)... [Pg.412]

Because of these complications, data from copolymerizations should be used with caution. Nevertheless, it appears that, for the copolymerization of 1,6-anhydroaldopyranoses, the major premises are met (as well as for radical copolymerization of vinyl monomers). [Pg.179]

Chirality induction can be achieved in homo- and copolymerization of vinyl monomers based on chiral monomer structure [1,3,8,9]. The first example of this type of polymerization was the copolymerization of (S)-a-methylbenzyl methacrylate with maleic anhydride the polymerization product showed [a]D +23° after removal of the chiral side group [73]. For another example, the copolymerization of an optically active styrene derivative (39) with N-phenylmaleimide (17, R = -Ph) followed by removal of the optically active side group and deboronation gave an optically active N-phenylmaleimide-styrene copolymer [74]. [Pg.766]

Graft and block copolymers of cotton cellulose, in fiber, yam, and fabric forms, were prepared by free-radical initiated copolymerization reactions of vinyl monomers with cellulose. The properties of the fibrous cellulose-polyvinyl copolymers were evaluated by solubility, ESR, and infrared spectroscopy, light, electron, and scanning electron microscopy, fractional separation, thermal analysis, and physical properties, including textile properties. Generally, the textile properties of the fibrous copolymers were improved as compared with the properties of cotton products. [Pg.332]

Relatively stable macroradicals have also been obtained by the polymerization of vinyl chloride (15) or by the copolymerization of this monomer with vinyl acetate (32) in poor solvents—i.e., by heterogeneous solution polymerization. Appropriate solvents for this type polymeriza-... [Pg.431]

Fullerenes and their water soluble derivatives are of great deal interest for scientific research due to their biological activity [1]. Therefor, the problems of modification and functionalization of nanomaterials to obtain their water soluble derivatives are very challenging task. In present work we have investigated low-temperature y -induced copolymerization of vinyl monomers such as acrylamide and acrylic acid with fullerene C6o to obtain their water soluble polymers containing fullerene. [Pg.481]

Copolymerization of vinyl chloride with metal salts of unsaturated carboxylic acids has been investigated more closely. By radical copolymerization in methanol solution of vinyl chloride and lead acrylate small amounts of lead acrylate can be inserted into the copolymer chains. However, only about one-third to one-half of the lead salt originally present in the monomer mixture is incorporated in the chains. Moreover, the thermal stability of the resulting polymer shows only a relatively small improvement over that of homopolymeric vinyl chloride (1) (see Figure 4). Although the rate of dehydrochlorination is distinctly lowered with increasing lead content in the polymers, there is no induction period at the onset of thermal treatment. Therefore, one cannot speak of true stabilization in this case. [Pg.88]

Tihe preparation and properties of cellulose graft copolymers have A been of considerable interest in the textile, paper, and wood products industries for a number of years. Both free radical- and ionic-initiated graft copolymerization reactions of vinyl monomers with cellulose have been reported. The vinyl-cellulose copolymers have some of the properties of both the cellulosic fibers and the grafted polyvinyl copolymers (I, 3, 47). [Pg.591]

Two important factors in initiating graft copolymerization reactions of vinyl monomers with activated cellulose are (1) the lifetime of the free radical sites and (2) the accessibility of the free radical sites to the monomers. For ceric ion initiation or hydroxyl radical initiation the lifetimes of the free radicals on the cellulose molecule were short (5, 19) therefore, the monomer should be present when the free radicals were formed. For ionizing radiation both short lived and long lived (trapped) free radicals were formed (22, 26, 44). Consequently, the activation reaction and the copolymerization reaction could either be conducted... [Pg.596]

A aubstantial amount of recent experimental data demonstrate that the model of styrene emulsion polymerization (1.2) on which the quantitative theory is based (, is not capable of adeqiiate interpretation of polymerization in many real systems. An attempt to use the theoretical relationships to describe polymerization of such industrially important monomers as vluyl acetate, vinyl chloride, alkylacrylates, as well as copolymerization of common monomers with functionally substituted ones, leads to a conclusion that the theory disregards some of the essential factors of the process. Therefore, this theory cannot be a foimdatlon for polymerization technology of the above monomers to be modernized and automatized. [Pg.62]


See other pages where Copolymerization of vinyl monomers with is mentioned: [Pg.541]    [Pg.212]    [Pg.1363]    [Pg.541]    [Pg.212]    [Pg.1363]    [Pg.228]    [Pg.464]    [Pg.506]    [Pg.535]    [Pg.551]    [Pg.11]    [Pg.171]    [Pg.600]    [Pg.40]    [Pg.841]    [Pg.228]    [Pg.348]    [Pg.165]    [Pg.119]    [Pg.464]    [Pg.466]    [Pg.4]   


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Copolymerabilities of monomers

Copolymerization monomers

Monomer copolymerization with

Vinyl copolymerizations

Vinyl monome

Vinyl monomer

Vinyl monomers copolymerization

Vinylic monomers

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