METHYACRYLIC ACID

A mixture consisting of water (190 g), ethyl alcohol (10 g), hexadecyl acrylate (70 g), hexyl acrylate (25 g), methyacrylic acid (5g), 3.2% sodium dodecyl sulfate, and ammonium dodecyl benzene sulfonate (5 g) was charged into a reactor and degassed for 30 minutes. Potassium persulfate (0.4 g) was then added, and the polymerization was conducted for 4 hours at 70°C under nitrogen. After the polymer was isolated, a sharp DSC endotherm was observed at 22.5°C. 

Table 7.28 Composition of major pyrolysates of butadiene (B) - acrylonitrile - (A) methyacrylic acid (M) terpolymers ...

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... 

A free flowing monomer, ethylene glycol dimethacrylate (EGD) stabilised with 0.1% hydroquinone is thickened with 0.0, 2.0, 4.0, 6.0, 8.0, 10.0, 12.0, 14.0 and 16.0% of methyacrylate butadiene styrene (MBS). Two further samples of the same monomer are thickened with similar increasing concentrations of cellulose nitrate (CN) and silicone dioxide (SiCh) for comparison. An accurate weight of 10.0 g of each thickened monomer is dissolved in 25% n-propanol and 75% glacial acetic acid. Then 0.25 ml of 1000 ppm Zn metal stock standard solution is added to each mixture. These solutions are also spiked with 0.5 ml of 1000 ppm indium (In) metal as internal standard. All mixtures are diluted to mark with the 25% n-propanol/glacial acetic acid. The mixtures contain 2.5 ppm Zn and 5.0ppm In per ml. 

Acrylic resins, particularly the methyacrylates, are somewhat resistant to acids, bases, weak and moderately strong oxidizing agents, and many corrosive industrial gases and fumes. 

It is interesting that the resonance of a-methyl protons in these copolymers is not as well resolved as is the methoxy proton resonance. Perhaps one would have to worry about pentad or triad stereochemical assignments if resolution were better. It is also worthwhile to call attention to the excellent resolution of a-methyl resonance patterns obtained in studies on the NMR spectra of copolymers of methyacrylates with aliphatic monomers such as methacrylic acid [25] or acrylonitrile [23 ]. It seems that the presence of aromatic rings in copolymers causes the resonance of neighboring nuclei to be broadened. This may be due to pentad, configurational or conformational effects. 

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