Methyl acrylate Specifications

Commercial Forms. Eour different base polymers of VAMAC ethylene—acryhc elastomer are commercially available (Table 1). Until 1990, existing grades of ethylene—acryhc elastomers were based on a single-gum polymer. VAMAC G, defined as a terpolymer of 55% methyl acrylate, ethylene, and a cure-site monomer (5). In 1991, a higher methyl acrylate terpolymer, VAMAC LS, was introduced. The composition of this polymer was specifically chosen because it significantly increases the oil resistance of the polymer while minimizing losses in low temperature fiexibihty (6). 

There are probably several factors which contribute to determining the endo exo ratio in any specific case. These include steric effects, dipole-dipole interactions, and London dispersion forces. MO interpretations emphasize secondary orbital interactions between the It orbitals on the dienophile substituent(s) and the developing 7t bond between C-2 and C-3 of the diene. There are quite a few exceptions to the Alder rule, and in most cases the preference for the endo isomer is relatively modest. For example, whereas cyclopentadiene reacts with methyl acrylate in decalin solution to give mainly the endo adduct (75%), the ratio is solvent-sensitive and ranges up to 90% endo in methanol. When a methyl substituent is added to the dienophile (methyl methacrylate), the exo product predominates. ... 

The conformational entropies of copolymer chains are calculated through utilization of semiempirical potential energy functions and adoption of the RIS model of polymers. It is assumed that the glass transition temperature, Tg, is inversely related to the intramolecular, equilibrium flexibility of a copolymer chain as manifested by its conformational entropy. This approach is applied to the vinyl copolymers of vinyl chloride and vinylidene chloride with methyl acrylate, where the stereoregularity of each copolymer is explicitly considered, and correctly predicts the observed deviations from the Fox relation when they occur. It therefore appears that the sequence distribution - Tg effects observed in many copolymers may have an intramolecular origin in the form of specific molecular interactions between adjacent monomer units, which can be characterized by estimating the resultant conformational entropy. 

Substitution reactions with (E)- or (Z)-vinylic halides usually show predominant retention of structure in the olefin substitution as they do in the carboalkoxylation, but the specificity is quite dependent on reaction conditions. Low reaction temperature, excess organophosphine, and dilution with excess trialkylamine and/or olefin all appear to improve the specificity. Under favorable conditions, for example, (Z)-l-bromo-l-hexene and methyl acrylate give an 82% yield of the (E, Z) and only 10% of the (E, E) isomer of methyl 2,4-nonadienoate 29). 

Labelled monomers have been used in co-polymerizations for analysis of the resulting co-polymers and consequent determination of monomer reactivity ratios (15, 16). This technique is of particular value when the compositions of the different monomer units are rather similar or when the co-polymer contains only very small amounts of one of the monomers. These points can be appreciated by considering calculations on co-polymers of methyl methacrylate and methyl acrylate summarized in Table 1. The analyses have been calculated ignoring contributions of end-groups it assumed that the acrylate ester is labelled with carbon-14 and that specific activities are expressed in units such as curies/g of carbon. 

No. mols. methyl methacrylate)/ (No. mols. methyl acrylate) in co-polymer Ana %C ysis of co-poI %H rcner %o (Specific activity of co-polymer)/(spedfic activity ol monomer)... 

Cyclic poly(methyl acrylate) with controlled ring size and its narrow distribution was synthesized by the 60Co y -ray-induced polymerization of methyl acrylate at - 30 °C in the presence of cyclic initiator without specific purification procedure as depicted in Fig. 5 [38]. The key point for synthe-... 

Vinyl lacquers are used mainly where a high degree of chemical resistance is required these lacquers are based on vinyl chlorides and vinyl acetates. Acrylic lacquers are based on methyl methacrylate and methyl acrylate polymers and copolymers. Other esters of acrylic and methacrylic acid also may be used to make nonconvertible film formers. Judicious selection of these acrylic acid or methacrylic acid esters allows one to produce film formers with specifically designed properties such as hardness, flexibility, gloss, durability, heat, and chemical resistance. Acrylic lacquers, however, are not noted for their water resistance. The principal uses of acrylic-type lacquers are fluorescent and metallic paints, car refinish applications, clear lacquers and sealers for metals, and protective coatings for aircraft components and for vacuum-deposited metals, as well as uses in pigmented coatings for cabinets and appliances. 

Fig. 10 Kind of phase portrait describing qualitatively the dynamics of tetrapolymerization of styrene, methyl methacrylate, 4-vinyl pyridine, and methyl acrylate, which is characterized by a set of kinetic parameters (5.23). In the diagram only specific lines (edges and separatrixes) are presented. Visible and invisible lines at a tetrahedron boundary are depicted as solid and dashed lines, respectively, and a line inside a tetrahedron is dotted...

Bolshakov et al. described low-temperature (100-130 K) polymerizations of acrylic acid, acrylamide, and methyl acrylate, in which radical mobility was strongly hindered by their specific interactions with the molecules of a melting alcohol matrix [50]. 

The fact that the rate of some Diels-Alder [4 + 2] cycloaddition reactions is affected, albeit only slightly, by the solvent was used by Berson et al. [52] in establishing an empirical polarity parameter called Q. These authors found that, in the Diels-Alder addition of cyclopentadiene to methyl acrylate, the ratio of the endo product to the exo product depends on the reaction solvent. The endo addition is favoured with increasing solvent polarity cf. Eq. (5-43) in Section 5.3.3. Later on, Pritzkow et al. [53] found that not only the endojexo product ratio but also the absolute rate of the Diels-Alder addition of cyclopentadiene to acrylic acid derivatives increases slightly with increasing solvent polarity. The reasons for this behaviour have already been discussed in Section 5.3.3. Since reaction (5-43) is kinetically controlled, the product ratio [endo]l[exo] equals the ratio of the specific rate constants, and Berson et al. [52] define... 

One is still however left with the problem of why, since poly(methyl acrylate) contains the highest carbonyl group concentration of all polyacrylates, does it show an unfavourable heat of mixing The answer lies in the neglection of contributions from dispersive forces. If one assumed that the dispersive and specific contributions could be separated. 

Data on the copolymers of styrene and a-methylstyrene and those of methyl acrylate (MA) and methyl methacrylate (MMA) are listed in Fig. 3. The extreme character of the dependence of IMM on copolymers of styrene and a-methylstyrene is quite understandable, if we recollect that the lower IMM of polystyrene chains than that of PM A may be associated not only with the large size of the phenyl ring but also with the specific interactions of the planes of neighboring jrfienyl rings The introduction of a-methylstyrene units prevents the mutual dispositions of the interacting phenyl rings and increases the IMM of the copolymer, if the content of a-methylstyrene units is low. At higher content of these units, the IMM of the copolymer approaches that of poly a-methylstyrene. 

Specifically mentioned monomers include methyl acrylate, ethyl acrylate, propyl acrylate (all isomers), butyl acrylates (all isomers), 2-ethylhexyl acrylate, isobornyl acrylate, acrylic acid, benzyl acrylate, phenyl acrylate, acrylonitrile, glycidyl acrylate,... 

Specific anion- and cation-reactant effects have been reported to play a role in Diels-Alder reactions [142-144], in particular for the em/oselectivity. Using the model reaction cyclopentadiene and methyl acrylate (Fig. 10, left) in various ionic liquids, the authors [142] demonstrated that the endo/exo ratio decreased when the reactions were carried out in [C4mim]+ homologues in the order of ... 

A lack of selectivity is also observed in the reaction of 1 with methyl acrylate which gives rise to the formation of the regioisomers methyl 7-methylenespiro[2.4]heptane-5-carboxylate (4) and methyl 7-methylenespiro[2.4]heptane-4-carboxylate (5) in a ratio that depends on the specific catalyst. ... 

Rann et al. reported the dramatic influence of a new tailor-made, task-specific, and stable ionic liquid, butyl methyl imidazolium hydroxide ([bmim][OH]), in Michael addition. They have discovered that a task-specific ionic liqnid [bmim][OH] efficiently promoted the Michael addition of 1,3-dicarbonyl compounds, cyano esters, and nitro alkanes to a variety of conjugated ketones, carboxylic esters, and nitriles withont reqniring any other catalyst and solvent (Fig. 12.21) [16]. Very interestingly, all open-chain 1,3-dicarbonyl componnds such as acetylacetone, ethyl ace-toacetate, diethyl malonate, and ethyl cyanoacetate reacted with methyl vinyl ketone and chalcone to give the usual monoaddition products, whereas the same reactions with methyl acrylate or acrylonitrile provided exclusively bis-addition products. 

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