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Copolymerization functional monomers

Other crosslinking reactions may be triggered by a catalyzed reaction between different units of a copolymerized functional monomer, such as A -methylol acrylamide or a copolymerized silane compound [86]. [Pg.498]

Complex Coordination Polymerization. It is difficult to copolymerize functional monomers having a phenolic moiety, like 2-hydroxybenzophenone, 2-(2-hydroxy-... [Pg.96]

Interestingly, copolymerized functional monomers like acrylic acid, for example, results in an increase in cohesion (Fig. 8-6) and produces a significant increase in the shear strength. [Pg.197]

Small amounts of specially functionalized monomers are often copolymerized with acryUc monomers in order to modify or improve the properties of the polymer. These functional monomers can bring about improvements either directiy or by providing sites for further reaction with metal ions, cross-linkers, or other compounds and resins. Table 9 Hsts some of the more common functional monomers used in the preparation of acryUc copolymers. [Pg.166]

Table 9. Functional Monomers for Copolymerization with Acrylic Monomers... Table 9. Functional Monomers for Copolymerization with Acrylic Monomers...
There are two main advantages of acrylamide—acryUc-based flocculants which have allowed them to dominate the market for polymeric flocculants in many appHcation areas. The first is that these polymers can be made on a commercial scale with molecular weights up to 10—15 million which is much higher than any natural product. The second is that their electrical charge in solution and the charge density can be varied over a wide range by copolymerizing acrylamide with a variety of functional monomers or by chemical modification. [Pg.33]

Styrene monomer was also copolymerized with a series of functional monomers by using a single-step dispersion copolymerization procedure carried out in ethanol as the dispersion medium by using azobisizobu-tyronitrile and polyvinylpyrollidone as the initiator and the stabilizer, respectively [84]. The comonomers were methyl methacrylate, hydroxyethyl acrylate, metha-crylic acid, acrylamide, allyltrietoxyl silane, vinyl poly-dimethylsiloxane, vinylsilacrown, and dimethylamino-... [Pg.216]

The soapless seeded emulsion copolymerization method was used for producing uniform microspheres prepared by the copolymerization of styrene with polar, functional monomers [115-117]. In this series, polysty-rene-polymethacrylic acid (PS/PMAAc), poly sty rene-polymethylmethacrylate-polymethacrylic acid (PS/ PMMA/PMAAc), polystyrene-polyhydroxyethylmeth-acrylate (PS/PHEMA), and polystyrene-polyacrylic acid (PS/PAAc) uniform copolymer microspheres were synthesized by applying a multistage soapless emulsion polymerization process. The composition and the average size of the uniform copolymer latices prepared by multistage soapless emulsion copolymerization are given in Table 11. [Pg.217]

The synthetic methods of macromolecules having an active pendant group include (1) the transformation reactions of polymer and copolymers, and (2) polymerization and copolymerization of functional monomers having active pendant groups. The macromolecules, either in the shape of film or microbeads, can be used as the substrate. As we have mentioned previously, the rate of polymerization initiated with the Ce(IV) ion redox system is much faster than that initiated by Ce(l V) ion alone, as expressed in / r 1. Therefore, the graft... [Pg.547]

Functional and end-functional polymers are precursors to block and graft copolymers and, in some cases, polymer networks. Copolymers with in-chain functionality may be simply prepared in copolymerizations by using a functional monomer. However, obtaining a desired distribution requires consideration of the chain statistics and, for low molecular weight polymers, the specificity of the initiation and termination processes, l hese issues are discussed in Section 7.5.6... [Pg.374]

A few functional dihalides have been prepared. Some of these monomers are tabulated in Table 6.2. The monomers could be nitrated and then reduced to amine-functionalized monomers (Scheme 6.26).203 This approach was used to nitrate DCDPS or bis-4-fluorophenyl phenyl phosphine oxide.204 These monomers were used to copolymerize with some other activated dihalides as the comonomers. [Pg.356]

Ionic polymers are a special class of polymeric materials having a hydrocarbon backbone containing pendant acid groups. These are then neutralized partially or fully to form salts. lonomeric TPEs are a class of ionic polymers in which properties of vulcanized rubber are combined with the ease of processing of thermoplastics. These polymers contain up to 10 mol% of ionic group. These ionomeric TPEs are typically prepared by copolymerization of a functionalized monomer with an olefinic unsamrated monomer or direct functionalization of a preformed polymer [68-71]. The methods of preparation of various ionomeric TPEs are discussed below. [Pg.115]

Figure 1. Possible strategies for the synthesis of functional microgel stabilizers functionalization of preformed microgels (left) or copolymerization of suitable functional monomers (right, our approach). (Reprinted from Ref. [13b], 2003, with permission from Wiley-VCH.)... Figure 1. Possible strategies for the synthesis of functional microgel stabilizers functionalization of preformed microgels (left) or copolymerization of suitable functional monomers (right, our approach). (Reprinted from Ref. [13b], 2003, with permission from Wiley-VCH.)...
Reactive polymers can be synthesized by either polymerizing or copolymerizing monomers containing the desired functional groups, or performing one or more modifications on a suitable polymer to introduce the essential functionality. Polymers produced directly by polymerization of functionalized monomers have well defined structures, but the physical and mechanical properties of the... [Pg.4]

Spectacular achievements in catalytic asymmetric epoxidation of olefins using chiral Mnm-salen complexes have stimulated a great deal of interest in designing polymeric analogs of these complexes and in their use as recyclable chiral catalysts. Techniques of copolymerization of appropriate functional monomers have been utilized to prepare these polymers, and both organic and inorganic polymers have been used as the carriers to immobilize these metal complexes.103... [Pg.454]

To design amphiphilic and/or reactive copolymers containing aliphatic polyesters, one of the most promising approaches is copolymerization with functional monomers having protected reactive side-chain groups. Some kinds of monomers having reactive (hydrophilic) side-chain groups have been reported (Fig. 3). Recently, the synthesis of various types of functional polyesters has been reviewed [15-19],... [Pg.72]

However, despite nearly 50 years of intense activity and progress, there are no commercially viable catalysts for the polymerization of acrylates or the controlled copolymerization of simple olefins with polar functional monomers. The development of a catalytic system capable of such controlled copolymerization would constitute a quantum advance in the plastics industry. [Pg.162]

The results of the block copolymerization of St, MMA, AA, and VAc with the polymers obtained by 7 and 8 are shown in Table 3. The yields of the block copolymers with 42 and 43 were as high as 70-90%. These block copolymer syntheses are advantageous for the synthesis of the polymer consisting of many kinds of vinyl monomer units, especially polar and functional monomers. [Pg.105]

For example, a proline-based chiral ligand was attached to a vinyl-substituted monomer (Fig. 42.15) by reacting vinylbenzoyl chloride with the amine functionality of the ligand [106]. As mentioned previously, the apolar Merrifield resin as a support is not swollen in polar solvents. Hence, in order to match the polarity of the resin with that of the typically used substrates in enantioselective hydrogenation, the functionalized monomer was copolymerized with polar units of methacrylic acid 2-hydroxyethyl ester. [Pg.1448]

There are two principal ways to synthesize functional fluoropolymers (a) polymerization of functional fluoromonomers or copolymerization of fluoro-olefins with functional monomers, and (b) modification of common... [Pg.91]

Radical copolymerization of TFE with hydrocarbon functional monomers has also not been widely used, owing perhaps to the high activity in the reaction with the C—H bond with its high probability of chain transfer to the monomer and the polymer, which is a feature of growing perfluoroalkyl radicals, and to poor chemical stability of the copolymers. [Pg.92]

As was noted above, functional fluoropolymers produced by copolymerization of fluoroolefins with functional PFAVE have several unique properties, with the main disadvantage of these materials being the extremely high cost of functional monomers and the resulting high cost of the functional polymers produced from them. The fact that they are so expensive limits their wider industrial application in other fields such as catalysis and membrane separation, except for chlorine-alkali electrolysis and fuel cells, where the only suitable materials are fully fluorinated polymers because of the extreme conditions associated with those processes. [Pg.93]


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See also in sourсe #XX -- [ Pg.529 ]




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Copolymerization monomers

Functional monomers

Functionalized monomers

Monomer functionality

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