Polyfmethacrylic acid

Fig. 15. Energy of proton dissociation (Ez) from Z times ionized polyelectrolyte molecules as function of the degree of dissociation (a). (A) - PPAL (1), PPAS (2), PPA (3), polyfmethacrylic acid) (4), copolymer of acrylic acid with ethylenesulfonic acid (50 50) in aqueous solutions (5), (B) - PPAL (1), PPAS (2), PPA in the presence of NaCl (3) ( ) INaClj = 0 (X) fNaCll = 0.25 mmol/1 (o) 0.50 mmol/1...

In a related application, polyelectrolyte microgels based on crosslinked cationic poly(allyl amine) and anionic polyfmethacrylic acid-co-epoxypropyl methacrylate) were studied by potentiometry, conductometry and turbidimetry [349]. In their neutralized (salt) form, the microgels fully complexed with linear polyelectrolytes (poly(acrylic acid), poly(acrylic acid-co-acrylamide), and polystyrene sulfonate)) as if the gels were themselves linear. However, if an acid/base reaction occurs between the linear polymers and the gels, it appears that only the surfaces of the gels form complexes. Previous work has addressed the fundamental characteristics of these complexes [350, 351] and has shown preferential complexation of cationic polyelectrolytes with crosslinked car-boxymethyl cellulose versus linear CMC [350], The departure from the 1 1 stoichiometry with the non-neutralized microgels may be due to the collapsed nature of these networks which prevents penetration of water soluble polyelectrolyte. 

When the atactic poly(a,a-dimethylbenzyl methacrylate) was heated at 170°C for 30 min under vacuum, it decomposed into volatile and nonvolatile components. The former was found to be a-methylstyrene and the latter was to be very similar to polyfmethacrylic acid) as determined by H NMR spectroscopy. Figure 3 shows the infrared spectra of atactic and isotactic poly(a,a-dimethylbenzyl methacrylate)s heated at 174°C under vacuum for various times. In the spectra of the atactic polymer, the absorption of the ester carbonyl at 1729 cm-1 decreased and that of the acid carbonyl at 1700 cm-1 increased as the heating time increased. After heating for a period of 30 min... 

Extracted polymer material had an IR spectrum identical with an authentic sample of polyfmethacrylic acid). They also report data on Mw (85.000 in 0.002 M HC1) and tacticity of the polyfmethacrylic acid) obtained. On the basis of Kunitake s fundamental investigation of vesicle forming dialkylammonium salts 14) similar results were reported recently by J. E. Brady u2). 

The conductivity of poly(acrylic acid) and polyfmethacrylic acid) has been measured as a function of orientation (65). Little effect is seen. It is suggested that orientation effects depend upon the nature of the polymer chain-like molecules show a slight decrease in conductivity on orientation, whereas that of globular molecules increases. 

Ulanski P, Merenyi G, Lind J, Wagner R, von Sonntag C (1999) The reaction of methyl radicals with hydrogen peroxide. J Chem Soc Perkin Trans 2 673-676 Ulanski P, Bothe E, Hildenbrand K, von Sonntag C (2000) Free-radical-induced chain breakage and depolymerization of polyfmethacrylic acid). Equilibrium polymerization in aqueous solution at room temperature. Chem Eur J 6 3922-3934... 

Ulanski P, Bothe E, von Sonntag C (1999b) OH radical induced depolymerization of polyfmethacrylic acid). Nucl Instr Methods Phys Res B 151 350-355... 

Fig. 35 Color change of polystyrene-fcZocfc-polyfmethacrylic acid) and imidazole-terminated side-chain mesogens PS-h-PMAA(LC) (Scheme 13) due to a shift in photonic handgap accompanying isotropization [171]...

The PL method has been used to investigate the IMM of the maaomolecules of carboxymethylcellulose (CMC) Anthrylacyloxymethane luminescent groups were used as LM. It was found that the presence of the cellobiose units in the main chain or the formation of intramolecular hydrogen bonds leads to a marked decrease in IMM. The value of r for CMC in water is 57 ns. As Tables 11,12 show, these high values of t are characteristic of the IMM of macromolecules with the elements of the internal structure such as polyfmethacrylic acid) (PM AA) in water. For non-ionized PMAA in water, is ca. 77 ns for LM in the side chain 9-anthrylmethyl-oxycarbonyl groups). 

The second mechanism (2) utilizes the change iMuced in the intramolecular interaction between pendant groups by photoirradiation. The system reported for the first time is polyfmethacrylic acid) with pendant azobenzene groups [4]. In an aqueous solution, the viscosity was found to increase by ultraviolet irradiation (Fig. 2(2a). The trans to cis photoisomerization was considered to decrease the hydro-phobic interaction between the azobenzene chromophor, allowing the polymer coil to expand. 

Tkachenko, N.H. et al.. Influence of polyfmethacrylic acid) on aggregative stability and electrical surface properties of aqueous suspensions of titanium dioxide. Colloids Surf. A, 279, 149, 2006. 

Hasa J, Ilavsky M, Dusek K. Deformational, swelling, and potentiometric behavior of ionized polyfmethacrylic acid) gels. I. Theory. J Polym Sci, Polym Phys Edn 1975 13 253-262. 

In this work, we have adapted the PMP method originally developed by Otsu et al. to prepare polyfmethacrylic acid) (PMAA) brushes on silicon surfaces, which are covered with native Si02. The PMP method is based on dithiocarbamate... 

Glutaraldehyde-cross-linked to partially hydrolysed caprone (poly-e-caproamide, nylon 6) thread Immobilized within a polyfmethacrylic acid) gel... 

Lysozyme Polyfmethacrylic acid)/poly (acrylic acid) Insoluble complexes [119]... 

Fig. 33. Schematic illustration of a polymer composite functioning like a bimetal and the profile of its bending Gel polyfmethacrylic acid), plastic poly(vinyl chloride) electric field 0.25 V/cm numbers indicate time (min) elapsed after electric field was imposed...

Polyfsodium acrylate) Polyfmethacrylic acid) Poly(methyl methacrylate)... 

Dicyclohexylcarbodi-imide (DCC) can also be used in conjunction with the alcohol of choice for esterification of such acids, but quantitative conversion is difficult. With a syndiotactic polyfmethacrylic acid) sample it was observed, by means of n.m.r., that in the partially esterified polymer the reacted and unreacted acid groups tend to alternate. This can be explained if it is supposed that esterification with DCC proceeds via the O-acylisourea to the cyclic anhydride which is then cleaved by the alcohol to ester and acid. Alternation arises because the anhydride forms predominantly between neighbouring methacrylic acid groups. 

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