Kinetic studies methyl acrylate

Solvent effects including 2-methyl-l,3-dioxepane (MDOP), as a solvent, on the propagation kinetics of methyl acrylate (MMA) have been investigated using the PLP-SEC technique (PLP = pulse laser polymerization) <2005MI267>, and the composition of dioxolane-dioxepane copolymers has been studied by IR and differential scanning calorimetry (DSC) <2004PB349>. 

Vinyhdene chloride copolymerizes randomly with methyl acrylate and nearly so with other acrylates. Very severe composition drift occurs, however, in copolymerizations with vinyl chloride or methacrylates. Several methods have been developed to produce homogeneous copolymers regardless of the reactivity ratio (43). These methods are appHcable mainly to emulsion and suspension processes where adequate stirring can be maintained. Copolymerization rates of VDC with small amounts of a second monomer are normally lower than its rate of homopolymerization. The kinetics of the copolymerization of VDC and VC have been studied (45—48). 

Studies of the copolymerization of VDC with methyl acrylate (MA) over a composition range of 0—16 wt % showed that near the intermediate composition (8 wt %), the polymerization rates nearly followed normal solution polymerization kinetics (49). However, at the two extremes (0 and 16 wt % MA), copolymerization showed significant auto acceleration. The observations are important because they show the significant complexities in these copolymerizations. The auto acceleration for the homopolymerization, ie, 0 wt % MA, is probably the result of a surface polymerization phenomenon. On the other hand, the auto acceleration for the 16 wt % MA copolymerization could be the result of Trommsdorff and Norrish-Smith effects. 

Polymers in Schemes 12 and 13 were the first examples of the preparation of pyridinium and iminopyridinium ylide polymers. One of the more recent contributions of Kondo and his colleagues [16] deals with the sensitization effect of l-ethoxycarbonyliminopyridinium ylide (IPYY) (Scheme 14) on the photopolymerization of vinyl monomers. Only acrylic monomers such as MMA and methyl acrylate (MA) were photoinitiated by IPYY, while vinylacetate (VA), acrylonitrile (AN), and styrene were unaffected by the initiator used. A free radical mechanism was confirmed by a kinetic study. The complex of IPYY and MMA was defined as an exciplex that served as a precursor of the initiating radical. This ylide is unique in being stabilized by the participation of a... 

Kochi (1956a, 1956b) and Dickerman et al. (1958, 1959) studied the kinetics of the Meerwein reaction of arenediazonium salts with acrylonitrile, styrene, and other alkenes, based on initial studies on the Sandmeyer reaction. The reactions were found to be first-order in diazonium ion and in cuprous ion. The relative rates of the addition to four alkenes (acrylonitrile, styrene, methyl acrylate, and methyl methacrylate) vary by a factor of only 1.55 (Dickerman et al., 1959). This result indicates that the aryl radical has a low selectivity. The kinetic data are consistent with the mechanism of Schemes 10-52 to 10-56, 10-58 and 10-59. This mechanism was strongly corroborated by Galli s work on the Sandmeyer reaction more than twenty years later (1981-89). 

Bowden has studied the application of the Hammett equation to the kinetics of the reaction of c/s-3-substituted acrylic acids with diphenyldiazom ethane (59) and with methanol (69) and the rates of alkaline hydrolysis of c -3-substituted methyl acrylates (69). The sets studied are reported in Table XII. Results of the... 

Breitenbach and Frank (5) showed that with styrene-divinylbenz-ene, no further additives (such as peroxides) are necessary for popcorn polymer formation. Breitenbach and Fally (6) found, in methyl acrylate polymerization, the possibility of crosslinking in the polymerization of a monovinyl compound. Miller and coworkers (7) developed the kinetics of the process Pravednikow and Medvedev (8) studied the chain scission, and assumed radical formation by that process as an important step. 

Tanaka, H. Yoshida, S. Kinetic study of the radical homopolymerization of captodative substituted methyl a-(acyloxy)acrylates. Macromolecules 1995, 28, 8117-8121. 

Mohanty S, Santra RN, Nando GB (1997) Reactive blending of ethylene-methyl acrylate copolymer and poly-dimethyl siloxane rubber kinetics studies from infrared spectroscopy. Adv Poly Technol 16(4) 323—329... 

Gerrens and Kuchner (7) studied styrene and methyl acrylate, Berrens ( ) used vinyl chloride, Gonzalez (9 ) studied methyl methacrylate, Senrui et al. (10) examined ethylene, and Greene (11) studied MMA cind vinyl acetate. These workers have all presented experimental data but none have offered a complete CSTR model based on fundamental kinetic equations. 

Aqueous emulsions of styrene, methyl methacrylate, methyl acrylate, and ethyl acrylate were polymerized with y-radiation from a Co source in the presence of sodium dodecyl sulfate or sodium laurate. The continuous measurement of conversion and reaction rate was carried out dilato-metrically. The acrylates polymerized fastest and the over-all polymerization rate increased as follows styrene < methyl methacrylate < ethyl acrylate methyl acrylate. The effects of radiation dose, temperature, and original monomer and emulsifier concentrations were studied with respect to the following factors properties of polymer dispersions, number and size of polymer particles, viscometrically determined molecular weights, monomer-water ratio, and kinetic constants. 

A kinetic study of living radical polymerizations of acrylates initiated by the (tetramesitylporphyronato)-cobalt(III) organo complexes (TMP)Co—CH(CH3)C02-Me and (Br8TMP)Co—CH(CH3)C02Me has been reported by Wayland et al.122 They applied an initial excess of the free cobalt complex and obtained the equilibrium constant for the reversible dissociation of the complex—poly(methyl acrylate) bond as K = 4.2 x 10 10 M for (TMP)Co and K= 1.3 x 10 8 M for (BrgTMP)Co from the rate of monomer consumption at 50 °C. The temperature dependence led to a bond... 

A kinetic study has been carried out on the methyl acrylate addition to butadiene in benzene, with and without AICI3 as catalyst The rate-law has the form of eqn. (15), case (c). The ratio amounts to 10 at 20°C. The activation parameters are... 

Xanthenyliumsodium (from sodamide and xanthene) reacts with aziridines to give a mixture of 9-mono- (271) or 9,9-di-substituted xanthenes (272).Addition of perchloric acid to unsymmetric allenes such as the 9-xanthylidene derivative (273) (prepared by a new route from 9,9-dichloroxanthene and an alkene) gave a red xanthylium salt (274), which was converted into a colourless spiro-indene (275) on heating.Full details have now been published of the properties and of the reactions of 9-diazoxanthene (276) and 9-xanthylidene (278) with methyl acrylate, substituted styrenes, several ketones, and alkyl-benzenes. The kinetics of the reaction with styrenes were studied and the conversion of (276) into (278) was achieved by photolysis of the tosylhydrazone (277) at —25 °C. 

In polymerization of /S-monoalkyl itaconates and lA [56], the polymerization reactivities were higher than those of DRI and MRI, and independent of the structure of R, It indicates that the effect of the alkyl groups on the polymerization reactivity appears more importantly in R than R. In fact, it was found that the polymerization reactivity of methyl cr-(tert-butoxycarbonylmethyl)acrylate (MtBI-II) was higher than that of tert-butyl a (methoxycarbonylmethyl)acrylate (MtBI-I). Recently, from the kinetic studies by means of ESR spectroscopy [57-60], the substituent effects of the ester alkyl groups on Ap and At were investigated [60] and... 

Crosslinked styrene (St)/maleic anhydride (MA) eopolymers have been synthesized, hydrolyzed with dicarbojgrlie aeid, and converted to bear dihydrojg hosphino functionalities. On the dihydro3QT>hosphino-funetionalized styrene-methyl acrylate (20% divinylbenzene) copolymer, the adsorption of Pb showed a linear relationship with the concentrations and fitted the Langmuir isotherm. The kineties of Pb adsorption on this dihydrojg hosphino-functionalized eopolymer were studied. The metal-ion adsorption kinetics of this copolymer appeared to show particle diffusion. They explained that the moving boundary advanced from the surface of the molecule towards the center. ... 

The batch emulsion copolymerisation of vinyl acetate and acrylic acid, methyl acrylate and acrylamide was investigated at 25C with a redox initiator system and a complex emulsifier. The kinetic behaviour of the copolymerisation and the structure of the resulting copolymers, as well as the particle size and number density of the latexes, were studied as a function of the conversion and the reaction time. 10 refs. 

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