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Methacrylic acid substitution

Similar mechanical data for a series of ionomers derived from a single ethylene—acryflc acid copolymer have appeared (13) (Table 3). Comparison of the data from Tables 2 and 3 shows that the substitution of acryflc acid for methacrylic acid has only minor effects on properties. [Pg.405]

Five-membered ring imides in cyclopolymers of N-substituted dimethacrylamides such as PSPDM can be hydrolyzed to amic acids under moderately basic conditions. The resulting N-substituted amide is extremely resistant to basic hydrolysis. Consequently, this basic hydrolysis approach can still not be employed for the preparation of head-to-head poly(methacrylic acid). [Pg.298]

Alternatively, esterification of carboxylic acid can be carried out in aqueous media by reacting carboxylic acid salts with alkyl halides through nucleophilic substitutions (Eq. 9.10).20 The reaction rate of alkyl halides with alkali metal salts of carboxylic acids to give esters increases with the increasing concentration of catalyst, halide, and solvent polarity and is reduced by water. Various thymyl ethers and esters can be synthesized by the reactions of thymol with alkyl halides and acid chlorides, respectively, in aqueous medium under microwave irradiation (Eq. 9.11).21 Such an esterification reaction of poly(methacrylic acid) can be performed readily with alkyl halides using DBU in aqueous solutions, although the rate of the reaction decreases with increasing water content.22... [Pg.304]

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]

Electrophilic addition reactions. See also Addition reactions with butylenes, 4 405-408 of maleic anhydride, 75 490 with methacrylic acid/derivatives, 76 236-237 of propylene, 20 774 Electrophilic aromatic substitution, benzene, 3 599-601 Electrophilic attack, at nitrogen and carbon, 27 98... [Pg.309]

Itaconic Acid. Structurally an a-substituted methacrylic acid, itaconic acid constitutes a C5 building block with significant market opportunities. It is currently produced via fungal fermentation at about 10,000 t/a and mainly used as a specialty comonomer in acrylic or methacrylic resins, as incorporation of small amounts of itaconic acid into polyacrylonitrile significantly improve their dyeability. [Pg.41]

In this article we will describe two different types of positive electron-beam resists, which were briefly reported in our previous communications (2,3). One is the homopolymer or copolymer with methyl methacrylate and a-substituted benzyl methacrylate, which forms methacrylic acid units in the polymer chain on exposure to an electron-beam and can be developed by using an alkaline solution developer. In this case, the structural change in the side group of the polymer effectively alters the solubility properties of the exposed polymer, and excellent contrast between the exposed and unexposed areas is obtained. The other is a self developing polyaldehyde resist, which is depolymerized into a volatile monomer upon electron-beam exposure. The sensitivity was extremely high without using any sensitizer. [Pg.399]

Water-soluble polymer-bound porphorins have been prepared by the reaction of poly(methacrylic acid) and poly(N-vinyl pyrrolidone-co-methacrylic acid) with the low-molecular weight substituted Zn complexes tetraphenylpor-phorin, phthalocyanins and naphthocyanins [67, 68]. These reactions are... [Pg.105]

Unsaturated tetrahydropyran derivatives have received only cursory attention in the literature as heterocyclic monomers. 2,3-Dihydropyran and several of its substituted derivatives apparently undergo cationic polymerization in a manner typical of vinyl ethers (72MI11103), while tetrahydropyranyl esters of methacrylic acid (123) are fairly typical free radically polymerizable monomers (Scheme 35) (74MI11105). The THP group was used in this study as a protecting group for the acid functionality, and it was found that deprotection of polymers (124) could be accomplished under extremely mild conditions. [Pg.287]

Mechanical Properties. Table I shows the general range of mechanical properties available in commercial Surlyn ionomers. Tile substitution of acrylic acid fur methacrylic acid has only minor effects on properties. [Pg.868]

Heteropoly catalysts have significant activities for the oxidation of isobutane into methacrolein and methacrylic acid. The yield increased up to 6% by vanadium substitution or salt formation, as follows. With Cs2.5Ni0.08H0.34+JrPV,Mo12 - O40, the highest conversion and selectivity were observed at x 1 (355). Increases in the reaction temperature to 613 K led to increased yields, up to 9.0%. A similar increase in the yield resulted from the substitution of As for P as a heteroatom or from the addition of various transition metals (106, 356). [Pg.220]

A fluorescent MIP chemosensor for determination of 9-ethyladenine was fabricated [56]. It contained porphyrin as a luminescent functional monomer. The interaction of 9-ethyladenine with the porphyrin quenched the MIP luminescence at 605 nm when excited at 423 nm. The polymer was sensitive to 9-ethyladenine in the range of 0.01-0.1 mM however, it was already saturated at 0.15 mM. The same researchers used vinyl-substituted zinc(II) porphyrin and methacrylic acid as functional monomers for imprinting of (-)-cinchonidine [57]. The MIP luminescence, when excited at 404 nm, was significantly quenched at 604 nm upon binding of (-)-cinchonidine, even in the low concentration range of 0.01-2 mM. [Pg.194]

By far the best monomers for GTP are the methacrylates. Glycidyl methacrylate and other substituted members of the family can be used to make highly functional block polymers. If the monomer contains active hydrogen, for example, hydroxyethyl methacrylate or methacrylic acid, GTP does not proceed. These functions can, however, be masked by trimethylsilyl groups [9] (Scheme 5). [Pg.6]

The following substances are recommended starting materials for unsaturated polyesters fumaric acid, maleic acid, methacrylic acid, adipic acid, phthalic acid, resi-nic acid, isophthalic acid, terephthalic acid, hydrated or halogenated phthalic acids, aliphatic and substituted aliphatic single and multi-functional alcohols up to C)8, alkoxylated and hydrated phenols and bisphenols, styrene, vinyltoluene, acrylic acid and methacrylic acid esters of the Ci-C4 alcohols, and tricyclodecane dimethanol. [Pg.37]

Dendrons attached as side chains on linear polymer chains behave different from free dendrimers and dendrons. Block copolymers, poly(3,5-bis(3,5-bis (benzyloxy)benzyloxy)-benzyl methacrylate-random-methacrylic acid)-block-poly(2-perfluorooctylethyl acrylate), possess poly(benzylether) dendrons and perfluorinated alkyl chains in their side chains (Fig. 4) [85], While an LB film of a copolymer with a medium substitution fraction of poly(benzylether) dendron side chain in poly(methacrylic acid) displays flat surface, a copolymer with high fraction of poly(benzylether) dendron side chains produces the zone texture. Dendron rich blocks are hydrophobic and oleophilic but perfluorinated blocks are solvophobic. Therefore, in this case, the solvophobicity-to-solvophilicity balance must be considered. As a result, copolymers with medium fraction of dendron are laid on solid substrate, but dendron blocks of copolymers with high fraction prefer to arrange at air side of air/ water interface and the fluorocarbon blocks are enforced to exist close to water subphase, resulting in the zone texture [86]. These situations of molecular arrangements at air/water interface are kept even after transfer on solid substrate. By contrast, when perfluorooctadecanoic acids are mixed with block copolymers with high dendron fraction, the flat monolayers are visualized as terrace [87], The monolayers are hierarchized into carboxyl, per-fluoroalkyl, and dendron layers, that is, hydrophilic, solvophobic, and oleophilic layers. In this case, perfluorooctadecanoic acids play a role for ordering of block copolymers. [Pg.227]

Radiation Curable Reactive acrylates-vinyl 2EHA, NVP, etc Multifunctional di or triacrylates same as conventional but are usually substituted with acrylic-methacrylic acids 10-30% multifunctional acrylate 10-50% polymer 20-50% reactive solvent... [Pg.58]

A high-capacity, weak-base anion-exchange resin has been prepared by suspension polymerization of methacrylic acid with DVB followed by the amination of the beads with an alkylamine. The resin has good anion-exchange properties and dimentional stability, and can be used in deionization of water as a substitute for silica... [Pg.92]

Ethenylbenzene is not the only ethenyl bonded monomer capable of undergoing copolymerization with diethenylbenzene (divinylbenzene), but commercially, the propenoic (acrylic) monomers are the alternatives which have been most widely exploited, since about 1950. For example, the methacrylic-divinylbenzene weakly acidic cation exchange resin [—RG(CH3)COOH] is made by copolymerizing diethenylbenzene and methylpropenoic acid (methacrylic acid) as shown in Scheme 2.3. Various alkyl substituted propenoic acid monomers may be employed in the manufacture of weakly acidic cation exchange resins, as are propenonitriles (acrylonitriles) and alkyl propenoates (acrylic esters). In the case of the two latter cited... [Pg.27]


See other pages where Methacrylic acid substitution is mentioned: [Pg.588]    [Pg.212]    [Pg.174]    [Pg.267]    [Pg.480]    [Pg.216]    [Pg.10]    [Pg.53]    [Pg.43]    [Pg.24]    [Pg.210]    [Pg.103]    [Pg.760]    [Pg.988]    [Pg.355]    [Pg.129]    [Pg.87]    [Pg.760]    [Pg.145]    [Pg.69]    [Pg.1348]    [Pg.129]    [Pg.3400]    [Pg.101]    [Pg.572]    [Pg.575]    [Pg.575]    [Pg.100]    [Pg.54]    [Pg.1410]   


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