Methyl methacrylic acid

According to their recent reports [11], 5 provides livingness of polymerization for styrene (ST) and methyl methacrylic acid (MA). Irrespective of the type of monomer, the initiator efficiency / was over 0.9, and the polydis-persity index, Mw/Mn (Mw weight-average molecular weight, Mn number-average molecular weight), was close to unity (approximately 1.2). The polymerization rate was very low (on the order of an hour), i.e., a very slow... 

PMMA is the polymer formed from the monomer starting material methyl methacrylic acid which has the chemical formula CH2 = C(CH3)(C02CH3). 

The cation exchanger, CB-4, consists of a copolymer of methyl methacrylic acid and divinylbenzene (DVB). 

E.26) (E.26) 2-Propenoic acid, 2-methyl-, methacrylic acid, prop-2-enoic acid, 2-methylacrylic acid 79-41-4]... 

Mitsubishi Rayon Co. of Japan also reported a manufacture of methyl methacrylic acid or its methyl ester from a catalytic oxidation of propionic acid or its methyl ester with titanium-vanadium-phosphorous-oxide (PVTiO) as its catalytic system. This reaction is very similar to the propionate-formaldehyde route except that it does not involve use of formaldehyde in the process. The reaction mechanism of this process is still unknown. 

Figure 13.2 Possible modifications to the natural rubber backbone by (a) catalysis to hydrogenated natural rubber, (b) interacting with maleic anhydride, and grafting with (c) polyacrylate, (d) methyl methacrylic acid, and (e) poly(methyl methacrylate).

The preparation of natural rubber-gra/t-methyl methacrylic acid has been reported by Lenka and coworkers. The vanadium ion was used as an initiator, which initiated the creation of free radicals on the backbone of natural rubber and this increased the interaction between the natural rubber and the methyl methacrylate surfaces. The coordination complexes derived from the acetylacetonate of Mn(III) ions could also be used as an initiator to form the natural rubber-gra/t-methyl methacrylic acid. Under different conditions, silver ions could be used as a catalyst to produce natural rubber-gra/t-methyl methacrylic acid with different concentrations of methyl methacrylic acid monomers, and potassium peroxydisulfate as an initiator. Consequently, these methods were successful in the preparation of compatible blended natural rubber and methyl methacrylic acid by graft copolymerization. This compatibility was confirmed by nuclear magnetic resonance and infrared spectroscopy techniques. The interaction between natural rubber and methyl methacrylic acid was significantly increased and was useful for further blending with other polyacrylate molecules or different polymer types. 

Thiraphattaraphun and coworkers also reported the thermal transition phenomena of the natural rubber-gru/i -methyl methacrylic acid obtained by the dynamic mechanical thermal analysis method. In the transition region, increasing the temperature resulted in a decrease in the storage modulus due to the increase in the chain stiffness of the polymer. Increasing the amount of... 

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