2- compared with methacrylic acid

Comparable process techniques involving the reaction of bisphenol A diglycidyl ether with methacrylic acid produce the corresponding hydroxy... 

Neoprene AF ( 963). It is a polychloroprene modified with methacrylic acid. Although it is a slow-crystallizing elastomer, the cohesive strength develops very rapidly and it has improved creep resistance at high temperature compared with Neoprene AC or AD. The improved properties of Neoprene AF are derived from the interaction between the carboxyl functionality with the metal oxides added in the solvent-borne polychloroprene adhesives. 

Photoresponsive membranes of cellulose-2,4-diacetate incorporating 6-nitro-l, 3, 3 -trimethylspiro-(2H-l-benzopyran-2,2 -indoline) have been prepared and chiroptical and fluorescence properties of optically active co-polymers of acenaphthalene with methyl acrylate/methacrylate have been investigated. Marked optical activity is induced in the aromatic units only for the co-polymer with methyl methacrylate. This difference in behaviour is associated with an overall higher main-chain flexibility and conformational freedom in acrylates compared with methacrylates. Photoisomerization in polyurethanes containing azo-links has been found to be dependent upon the thermal history of the polymer, and photoisomerization of linoleic acid and... 

Singh et al. [123] prepared hydrogel from Sterculia gum modified with methacrylic acid and loaded with Ranitidine HCl. It was observed that the amount of drug released from per gram of the gel is higher in pH 2.2 as compared to pH 7.4 and distilled water. The monomer concentration, initiator concentration, amount of sterculia gum and concentration of crosslinker used diu ing the synthesis of hydrogels have affected the pore size and network density, which have been reflected in the swelling of the polymer matrix. 

Selective methacrylation of the three OHs in chohc acid have been studied and the reactivity order is found to be C3 > C12 > C7 [213]. Attempts have also been made to improve the hydrophilicity of the bile acid-based (co)polymer conjugates and to explore their properties and potential application in aqueous systems. The OH at C3 position has been turned into NH2 and the methacrylamide derivatives of bile acids have been compared with methacrylate derivatives. The former are found to undergo more feasible (free radical) polymerization resulting in more hydro-phihc polymer [214, 215]. The stereoisomerism of the polymerizable moieties has also been studied. The 3p-epimers are found to polymerize more easily than 3a-epimers moreover, the polymer of the 3(3-epimers presents higher hydrophilicity. Further increased hydrophilicity is achieved by copolymerization with hydrophilic monomers, i.e., methacrylic acid and 2-hydroxyethyl methacrylate, and by selective... 

The oxidative dehydration of isobutyric acid [79-31-2] to methacrylic acid is most often carried out over iron—phosphoms or molybdenum—phosphoms based catalysts similar to those used in the oxidation of methacrolein to methacrylic acid. Conversions in excess of 95% and selectivity to methacrylic acid of 75—85% have been attained, resulting in single-pass yields of nearly 80%. The use of cesium-, copper-, and vanadium-doped catalysts are reported to be beneficial (96), as is the use of cesium in conjunction with quinoline (97). Generally the iron—phosphoms catalysts require temperatures in the vicinity of 400°C, in contrast to the molybdenum-based catalysts that exhibit comparable reactivity at 300°C (98). 

Copolymers of ethylene with up to 15-20% acrylic or methacrylic acid offer improved adhesion, abrasion resistance, toughness, and low-temperature flexibility compared to EVA. Applications include extrusion coatings on aluminum foil for pouches, wire and cable, packaging film, laminations with metal and glass fibers (building and automotive products) and polyurethane (carpet backing). 

As mentioned in Chapter 2, if two comonomers are not connected with the template by covalent bonds, reactivity ratios can be calculated on the basis similar to the conventional copolymerization. The only difference is that reactivity ratios ri and T2 for both monomers depend on the concentration of the template. In order to compare experimental data with these considerations, copolymerization of methacrylic acid with styrene was carried out in the presence of PEG (mol. wt. 20,000) as the template. The reactivity ratios rf and r2 can be calculated according to the Kellen-Tiidos method. The results are shown in the Figure 5.4. According to this method, a proper functions of monomer mixture composition, R, and copolymer composition, E, were plotted ... 

The formation of methacrylic acid units was clearly observed in the difference spectrum for the copolymer containing 74.7 mol% of methyl methacrylate units as shown in Figure 8. By comparing this spectrum with the... 

Compared with propene, the oxidation of isobutene is more rapid but less selective, yet selectivities of over 75% appear feasible. Combustion is the main side reaction. One would expect that some considerable attention would be shown in the literature to isobutene oxidation as a route to the industrially important methacrylic acid, but this is not the case. Nor is it with the production of methacrylonitrile, analogous to the propene ammoxidation. Only in the patent literature is a high activity noticeable. 

The preparation of cellulose copolymers with vinyl monomers, which have functional groups that are hydrophilic in nature, has given textile products with improved soil release properties. For example, as shown in Figure 5, crosslinked cellulose-poly (methacrylic acid) copolymer fabrics exhibited both increased oily and aqueous soil release during washing compared with the crosslinked control fabrics. However, for oily soil, when softeners were added to the wash water, this improvement in soil release decreased. Crosslinked cellulose-poly (hydroxyethyl methacrylate) copolymer fabrics exhibited no improvement in oily soil release and only slight improvement in aqueous soil release compared... 

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