Polymethyl acrylate

Polymethyl acrylate [9003-21-8]. Ppted from a 2% soln in acetone by addition of water. 

COOH Polyacrylic acid COOCH3 Polymethyl acrylate... 

Since alpha substituents also impede segmental motion, PMMA (Tg = 378 K) has a higher Tg than polymethyl acrylate (PMA) (7 = 279 K). The various factors which affect Tg values are additive. 

Most general purpose linear polymers, such as polyolefins, PS, PVC, and polymethyl methacrylate (PMMA), are not suitable for use at temperatures above 100 °C. PMMA and other polymers of 1,1-substituted vinyl monomers, such as poly-a-methylstyrene, decompose almost quantitatively to their monomers at elevated temperatures. However, the Tg and Tm values of these polymers are greater than those of polymers from 1-substituted vinyl monomers. For example, the Tg values of polymethyl acrylate (PMA) and PMMA are 276 and 381 K, respectively. 

For example polymethyl acrylate was treated with phosphorus penta-chloride to form copolymers containing 26.6 and 37.8% acid chloride units these copolymers, by treatment with tert-butyl hydroperoxide, yield 4.9 to 6% perester containing polymers which were used for grafting styrene, vinyl acetate, acrylonitrile (177). 

Fig. 2. Plots of various diffusion coefficients against penetrant concentration for the system polymethyl acrylate — benzene at 30° C o jD fromDa. D fromDj. (x) CfromD (determined from 5teady state permeabilities). Taken from unpublished paper of Kishimoto and Enda...

Fig. 3. Plots of D against penetrant concentration for the system polymethyl acrylate — ethyl acetate at different temperatures [Fujita, Kishimoto and Matsumoto (I960)]...

Fig. 12. Permeation curves of water for polymethyl acrylate at 20° C. Taken from unpublished experiments of Kishimoto...

Since it might be less interesting to reproduce details of these previous results, we wish to illustrate the applicability of the theory with our unpublished data for the system polymethyl acrylate-diethyl phthalate (DEP). To this end use is made here of the relation ... 

For a rigorous test of the theory this plot is more adequate, because it brings to focus the details of experimental data for small values of vt with which the present theory is essentially concerned. The same applies for the corresponding diffusion theory. Figure 17 shows iij/ln o vs. i j for the system polymethyl acrylate-DEP we studied. It is seen that at high temperatures Eq. 

Fig. 18. Values of /(0, T) and fi(T) for the system polymethyl acrylate—diethyl phthalate. Solidcircles show values of f[0,T) derived from diffusion data on polymethyl acrylate — benzene. Taken from unpublished results of Fvjita and Maekawa, and of Kishimoto and Ekda...

A. Kishimoto and K. Matsumoto Concentration and temperature dependence of diffusion coefficients for systems polymethyl acrylate and n-alkyl acetates. Trans. Faraday Soc. 56, 424 (1960). 

The free radical polymerization of acrylic anhydride has been shown (37) to proceed predominantly by alternating intramolecular and intermolecular propagation steps. The product after hydrolysis and methylation has been found to yield a polymethyl acrylate exhibiting considerable crystallinity (37). 

The newer type of colloidal catalysts have been prepared containing palladium (4), platinum (4), rhodium (5), and iridium (6). A variety of synthetic polymers has been applied. Among those tested were polyvinyl alcohol (PVA), polyvinyl acetate (PVAc), polymethyl methacrylate (PMMA), and polymethyl acrylate (PAMA). In general, polyvinyl alcohol (4a) has been found most satisfactory. 

FUjita, H., and E. Maekawa Viscosity behavior of the system polymethyl acrylate and diethyl phthalate over the complete range of composition. J. Phys. Chem. 66, 1053 (1963). 

Mattery G. R., S. M. Thesis, "Radiation Induced Crosslinking in Polymethyl acrylate", MIT, 1978. 

Polyethylene [9002-88-4]. Crystallise it from thiophen-free benzene and dry it over P2O5 under vacuum. Polymethyl acrylate [9003-21-8]. Precipitate it from a 2% solution in acetone by addition of water. Polyvinyl acetate [9003-20-7]. Precipitate it from acetone by addition of n-hexane. 

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