Methyl methacrylate chemical environment

USEPA (1985) Health and Environmental Effects Profile for Methyl methacrylate. NTIS-PB-178785. US. EPA-600/x-85-364. Vaishnav, D.D., Babeu, L. (1987) Comparison of occurrence and rates of chemical biodegradation in natural waters. Bull. Environ. Contam. Toxicol. 39, 237-244. 

Figure 3.26. Details of the XPS spectrum from a poly(methyl methacrylate) surface, showing (a) the carbon Is peak and (b) the oxygen Is peak. In each case internal structure corresponding to atoms in different chemical environments may be resolved. After Green et al. (1990).

Nuclear magnetic resonance (NMR) spectroscopy of polymers in solution is a very important method of studying polymer configuration since noncrystalline as well as crystalline compounds can be studied. The method depends on the fact that the chemical shift of the signals of bonded hydrogen atoms (protons), and atoms, etc., in fixed chemical environments depends on the configuration of the main chain. In theory, the technique represents an absolute method, but, on technical grounds, it can often only be used as a relative method. An example of this is the analysis of the spectra of poly(methyl methacrylates) of various tacticities. 

Furthermore, the C=C bonds in the natural rubber structure might induce poor thermal and oxidative resistance in the natural rubber blends. Thus, Thawornwisit and coworkersproposed the preparation of hydrogenated natural rubber, which is one of the chemical modifications available to improve the oxidation and thermal resistance of diene-based natural rubber before blending with poly(methyl methacrylate-co-styrene). The poly(methyl methacrylate-co-styrene) was resistant to the outdoor environment and had excellent optical properties with a high refractive index, but it was extremely brittle and had low impact strength. Hydrogenated natural rubber could, however, be used as an impact modifier, as well as to improve its thermal and oxidative resistance for these acrylic plastics. 

Fig. 5.17 (a) Chemical Structure of Poly (deuterated styrene)-W< cit-2-[2-(2-methoxyethoxy) ethoxy]ethyl methacrylate (dPS-b-PME3MA). (b) Schematic pictures of the conformations of dPS-b-PME3MA in a mixture with PS in air (or in a vacuum) and in water. At the surface in a vacuum or air, the terminal methyl groups of the side chains, circle, cover the stuface. In water, the water-soluble PME3MA blocks are anchored onto the surface of polystyrene and stretching out into water. PME3MA blocks cover the surface in either hydrophobic or hydrophilic environment... 

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