Polyfacrylic acid

The identification of anionic polyfacrylic acid) sizes can be carried out by staining with a fluorescent cationic dye (Cl Basic Orange 14) followed by spectroscopic measurement of excitation wavelength and fluorescence emission [195,196]. Such methods can also be used (with Cl Basic Orange 14 or Cl Basic Red 1) to detect and estimate carboxymethylcellulose, poly(vinyl alcohol) and starch derivatives [197]. 

Katono, H., Maruyama, A., Sanui, K., Ogata, N., Okano, T., and Sakurai, Y. Thermo-responsive swelling and drug release switching of interpenetrating polymer networks composed of poly(acrylamide-co-hutyl methacrylate) and polyfacrylic acid). J. Controlled Release 1991,16, 215-228. 

Aqueous Solvation of Hyperbranched Polyfacrylic Acid) Films... 

Scheme 4 Chemistry used to prepare hyperbranched polyfacrylic acid) grafts on polyethylene film, polyethylene powder or polypropylene wafers...

Fig. 9 Fluorescence spectra of a 5-PAA/PP wafer that was first aminoamidated with NH2CH2CH2N(CH3)2 and then treated with 11 in a pH 7 buffer. The first spectrum (a) is the ionic assembly that forms at pH 7 from ion pairing of-N(CH3)2H groups of the graft with - C02 groups of the polyfacrylic acid). The second spectrum (b) shows complete removal of 11 after treatment of the interface with 0.1 N NaOH (which converts the -N(CH3)2H groups to -N(CH3)2 groups)...

For bioadhesive applications, anionic polymers appear to provide the most effective balance between adhesiveness and toxicity, with carboxylic materials preferred over sulfonic polymers [400]. Polyfacrylic acid) microparticles have been identified as particularly effective bioadhesive materials [402]. Studies with poly(acrylic acid) microparticles have indicated that, while water-swollen particles exhibit good bioadhesion, dry polymer particles give no adhesion at all. In addition, adhesive strength increases as the degree of ionization of the polymer is increased [402]. Thus the expanded nature of the polymer network is important to mucoadhesion, probably via polymer interdiffusion and entanglement with mucin [403],... 

Seki and Tirrell [436] studied the pH-dependent complexation of poly(acrylic acid) derivatives with phospholipid vesicle membranes. These authors found that polyfacrylic acid), poly(methacrylic arid) and poly(ethacrylic acid) modify the properties of a phospholipid vesicle membrane. At or below a critical pH the polymers complex with the membrane, resulting in broadening of the melting transition. The value of the critical pH depends on the chemical structure and tacticity of the polymer and increases with polymer hydro-phobicity from approximately 4.6 for poly(acrylic acid) to approximately 8 for poly(ethacrylic acid). Subsequent photophysical and calorimetric experiments [437] and kinetic studies [398] support the hypothesis that these transitions are caused by pH dependent adsorption of hydrophobic polymeric carboxylic acids... 

Anionic polyelectrolytes have been shown to enhance resistance to bacteria and fungi, enhance immune response, inhibit adjuvent arthritis and either depress or stimulate phagocytic activity of the reticuloendothelial system [458,459]. Carboxylic acid polymers have shown interferon induction, antiviral activity, and tumor growth inhibition [460]. The effects include inhibition of sarcoma, leukemia, polyoma and vesicular stomatitis virus. In one application, the cytotoxicity of bleomycin toward cultured mammalian cells was synergisti-cally enhanced by stirring in the presence of high molecular weight polyfacrylic acid) [461]. 

Irradiation with 7-rays was also used to synthesize bimetallic nanoparticles. Remita et al. synthesized poly(vinyl alcohol) (PVA)-stabilized Ag/Pt bimetallic nanoparticles by radiolysis of an aqueous mixture of Ag2S04 and K2PtCl4 at a concentration of 10-4 mol dm-3. A typical Ag plasmon absorption band is observed at —410 nm with only low intensity at the mole ratio of Ag Pt = 60 40, indicating the formation of Ag/Pt bimetallic nanoparticles. Polyfacrylic acid) was also used as the stabilizer, although the resulting UV-Vis spectra were quite different. 

A recent example of the use of silylating agents in the derivatization of polymer surfaces is given by Davies and Munro s application of trimethyl-silylimidazole (TMSI) to polyfacrylic acid) (PA A) surface analysis [35]. Figure 5 shows the changes in core level XPS spectra for PA A after reaction with TMSI. Williams first proposed the use of TFSA for this purpose in 1981 [36] but this application was not subsequently published so we take this opportunity to provide more detail. 

Thomas JK (1967) Pulse radiolysis of aqueous solutions of methyl iodide and methyl bromide. The reactions of iodine atoms and methyl radicals in water. J Phys Chem 71 1919-1925 Tsang W, Hampson RF (1986) Chemical kinetic data base for combustion chemistry, part I. Methane and related compounds. J Phys Chem Ref Data 15 1086-1279 UlanskiP, von Sonntag C (1999) The OFI-radical-induced chain reactions of methanol with hydrogen peroxide and with peroxodisulfate. J Chem Soc Perkin Trans 2 165-168 Ulanski P, Bothe E, Hildenbrand K, von Sonntag C, Rosiak JM (1997) The influence of repulsive electrostatic forces on the lifetimes of polyfacrylic acid) radicals in aqueous solution. Nukleonika 42 425-436... 

Han P, Bartels DM (1994) Encounters of H and D atoms with 02 in water relative diffusion and reaction rates. In Gauduel Y, Rossky P (eds) AIP conference proceedings 298. "Ultrafast reaction dynamics and solvent effects." AIP Press, New York, 72 pp Hasegawa K, Patterson LK (1978) Pulse radiolysis studies in model lipid systems formation and behavior of peroxy radicals in fatty acids. Photochem Photobiol 28 817-823 Herdener M, Heigold S, Saran M, Bauer G (2000) Target cell-derived superoxide anions cause efficiency and selectivity of intercellular induction of apoptosis. Free Rad Biol Med 29 1260-1271 Hildenbrand K, Schulte-Frohlinde D (1997) Time-resolved EPR studies on the reaction rates of peroxyl radicals of polyfacrylic acid) and of calf thymus DNA with glutathione. Re-examination of a rate constant for DNA. Int J Radiat Biol 71 377-385 Howard JA (1978) Self-reactions of alkylperoxy radicals in solution (1). In Pryor WA(ed) Organic free radicals. ACS Symp Ser 69 413-432... 

Fig. 22. Effect of composition on the water content (S) and the initial modulus (E0) of the polyelectroiyte complex of polyfacrylic acid) (PAA)-poly(ethylenepiperazine)...

Diallylamine hydrochloride plus crosslinker Crosslinked polyfacrylic acid) 1.2... 

Maeda Y, Magara K, and Tsugaya H. Pervaporation of aqueous acetic acid mixture through polyfacrylic acid-co-acrylonitrile) membranes. PCX Int. Appl. 1993 JP 19910903. 

Structure V Complex formation between polyelfiyleneimine and polyfacrylic acid)... 

Figure 6.7.1. Variation of weight % loss for a polyfacrylic acid) sample in a TGA experiment at a heating rate of ICP C/min.

Table 6.7.1. Summary regarding reports on thermal decomposition of polyfacrylic acid) and of some of its salts.

Table 6.7.2. Compounds identified in the pymgram of polyfacrylic acid) = 1,000,000...

Dange, C. et al., Desorption mechanism and dispersion efficiency of three anionic additives [polyfacrylic acid), polyfstyrene sulfonate) and HEDP] on zinc oxide, J. Colloid Interf. Sci., 315, 107, 2007. 

Santhiya, D. et al.. Surface chemical studies on the competitive adsorption of polyfacrylic acid) and poly(vinyl alcohol) onto alumina, 7. Colloid Interf. Sci., 216, 143, 1999. 

Vedula, R.R. and Spencer, H.G., Adsorption of polyfacrylic acid) on titania (anatase) and zirconia colloids. Colloids Surf., 58, 99, 1991. 

---