Acrylic and Methacrylic Acids

In these equations I is the initiator and I- is the radical intermediate, M is a vinyl monomer, I—M- is an initial monomer radical, I—M M- is a propagating polymer radical, and and are polymer end groups that result from termination by disproportionation. Common vinyl monomers that can be homo-or copolymeri2ed by radical initiation include ethylene, butadiene, styrene, vinyl chloride, vinyl acetate, acrylic and methacrylic acid esters, acrylonitrile, A/-vinylirnida2ole, A/-vinyl-2-pyrrohdinone, and others (2). 

Acrylic and methacrylic acids and their esters are highly versatile materials in that the acid and ester side groups can partake in a variety of reactions to produce a very large number of polymerisable monomers. One particularly interesting approach is that in which two methacrylic groupings are linked together so that there are two, somewhat distant, double bonds in the molecule. In these cases it is possible to polymerise through each of these double bonds separately and this will lead eventually to a cross-linked network structure. 

Nickel carbonyl Carbonylation of acetylene and alcohols to produce acrylic and methacrylic acids Acute respiratory failure carcinogenic... 

MMA, styrene, 2-hydroxy ethyl methyacrylate, 2-hy-droxypropyl methacrylate, acrylic and methacrylic acids, acrylamide and N-vinyl pyrrolidone (NVP) [64]. By this process, polyurethane is partially converted to N-chloro or N-bromo derivatives by a short immersion... 

For flexible chain copolymers based on acrylic and methacrylic acids (AA and MA) crosslinked with a polyvinyl component, the inhomogeneity of the structures formed depends on the nature of the crosslinking agent, its content in the reaction mixture and the thermodynamic quality of the solvent [13,14],... 

The furfuryl esters of acrylic and methacrylic acid polymerize via a free-radical mechanism without apparent retardation problems arising from the presence of the furan ring. Early reports on these systems described hard insoluble polymers formed in bulk polymerizations and the cross-linking ability of as little as 2% of furfuryl acrylate in the solution polymerization of methylacrylate121. ... 

Monomers based upon acrylic and methacrylic acids, especially the meth-acrylics, form the most versatile and most important class of polymerizable mono-... 

Crawford developed cyanohydrin process for acrylic and methacrylic acid as follows ... 

Most of these monomers are inclined to violent polymerisation unless stabilised. Stabilisation usually involves oxygen as well as the nominal stabiliser. A kinetic study of the process for acrylic and methacrylic acids is reported. 

Oberly R, Tansy MF LC50 values for rats acutely exposed to vapors of acrylic and methacrylic acid esters, jf Toxicol Environ Health 16 811, 1985... 

The acrylic family of polymers includes polymers and copolymers of acrylic and methacrylic acids and esters, acrylonitrile, and acrylamide [Kine and Novak, 1985 Nemec and Bauer, 1985 Peng, 1985 Thomas and Wang, 1985],... 

Many other copolymers of commercial importance have been discussed previously see Secs. 3-14c (vinyl acetate, vinylidene chloride), 3-14d (acrylic and methacrylic acids and esters,... 

Please note due to differences in the copolymerization parameters of n-butyl acrylate and methacrylic acid a continuous addition of the monomer mixture is necessary in order to achieve a homogeneous composition of the copolymer product. 

The resins used are polymers and copolymers of the esters of acrylic and methacrylic acids. They range in physical properties from soft elastomers to hard plastics, and are used in cementitious compounds in much the same manner as SBR latex. Acrylics are reported to have better UV stability than SBR latex and therefore remain flexible under exterior exposure conditions longer than SBR latex [88]. 

The published results concerning polymerization of acrylic acid or methacrylic acid in the presence of polyCethylene oxide) in water are controversial. Ferguson and Shah found that PEG with sufficiently high molecular weight increases the polymerization rate, while Kabanov at al found that in the presence of high molecular weight PEG the rate of polymerization of acrylic and methacrylic acids is lower than in blank reaction. Our results show that in the case of methacrylic acid photopolymerization in the presence of PEG of mol. weight 20,000, the rate of the reaction increases. This differences can be explained by the conditions of polymerization as well as methods used to follow the process different in both studies. 

Was used in prepn of acrylate resins and of other copolymers and polymers. Acrylate resins are thermoplastic polymers or polymers of acrylic and methacrylic acid, esters of these acids or acrylonitrile. Acrylic acid acrylonitrile and their derivatives are described in Vol 1 of Encycl, pp A96-R A97. Methacrylic acid is a-methylacrylic acid,... 

Polyvinyl methyl ether and polymers of acrylic and methacrylic add are also water-soluble. Because of salt formation in the polymers, the acrylic and methacrylic acid polymers, as well as CMC, are more soluble in alkaline solutions than they are in water. 

Uses and Reactions. Camphene is used for preparing a number of fragrance compounds. Condensation with acids such as acetic, propionic, isobutyric, and isovaleric produce useful isobomyl esters. Isobomyl acetate (41) has the greatest usage as a pine fragrance (81). The isobomyl esters of acrylic and methacrylic acids are also useful in preparing acrylic polymers. 

By chemical agents, indirect grafting on Nylon in liquid phase is frequently referred to in the bibliography. The most common reagent is air (144) or ozone, under controlled conditions, in order to avoid deterioration on the mechanical properties of the fiber, which is then immersed in the monomer. Hence, styrene (145-149), vinylidene chloride (146), vinyl acetate (146), acrylic and methacrylic acids (149), methyl methacrylate (146), acrylonitrile (146,148,149), 2-methyl-5-vinylpyridine (149) were successfully employed as grafting comonomers. 

Acrylic Polymers. Although considerable information on the plasticization of acrylic resins is scattered throughout journal and patent literature, the subject is complicated by the fact that acrylic resins constitute a large family of polymers rather than a single polymeric species. An infinite variation in physical properties may be obtained through copolymerization of two or more acrylic monomers selected from the available esters of acrylic and methacrylic acid (30) (see Acrylic esterpolya rs Methacrylic acid and derivatives). 

The stable polymer dispersions with small-sized polymer particles of diameter >60 nm were prepared by dispersion copolymerization of PEO-MA macromonomer with styrene, 2-ethylhexyl acrylate, acrylic and methacrylic acids, and butadiene at 60 °C [79]. The particle size was reported to decrease with increasing macromonomer fraction in the comonomer feed. Besides, it varied with the type of the classical monomer as a comonomer. Tg of polymer product was found to be a function of the copolymer composition, the weight ratio macromonomer/monomer, and monomer type and varied from 50.6 to 220.4 °C. 

Acrylic and methacrylic acids are considered to be relatively toxic, both orally and by skin contact. In general, the presence of more than one carboxylic acid group per molecule, unsaturated bonds in the carbon skeleton, or the presence of a hydroxide group on the alpha-carbon position (see Figure 14.6) increases corrosivity and toxicity of carboxylic acids. 

The methyl, ethyl, and butyl esters of acrylic and methacrylic acids are polymerized under the influence of heat, light, and peroxides. The polymerization reaction is exothermic and may be carried out in bulk for castings, or by emulsion, or in solution. The molecular weight decreases as the temperature and catalyst concentration are increased. The polymers are noncrystalline and thus very clear. Such resins are widely used because of their clarity, brilliance, ease of forming, and light weight. They have excellent optical properties and are used for camera, instrument, and spectacle lenses. 

McDowall, D. J. Gupta, B. S. Stannett, V. T. Williams, J. L.5 Zahran, A. H. "Grafting of Acrylic and Methacrylic Acid to Cellulose Materials." National Joint Pacific Conference of ACS, Honolulu, Hawaii, April 1979. 

For food contact articles made from acrylic and methacrylic acid ester copolymers and their polymer blends, the following starting materials can be used ... 

The radical polymerization in aqueous solution of a series of monomers—e.g., vinyl esters, acrylic and methacrylic acids, amides, nitriles, and esters, dicarboxylic acids, and butadiene—have been studied in a flow system using ESR spectrometry. Monomer and polymer radicals have been identified from their ESR spectra. fi-Coupling constants of vinyl ester radicals are low (12-13 gauss) and independent of temperature, tentatively indicating that the /3-CH2 group is locked with respect to the a-carbon group. In copolymerization studies, the low reactivity of vinyl acetate has been confirmed, and increasing reactivity for maleic acid, acrylic acid, acrylonitrile, and fumaric acid in this order has been established by quantitative evaluation of the ESR spectra. This method offers a new approach to studies of free radical polymerization. 

Table I. Coupling Constants for Radicals from Acrylic and Methacrylic Acids and Acrylonitrile...

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