Agents, polymeric ammonium ions

Polyamines and their ammonium salts have been of interest because they are known to have potential applications as chelating agents (1-3), ion exchange resins (4-6), flocculants (7,8), and other industrial uses (9). Recent biomedical applications have constituted another important use of polymeric amines they have been investigated for use as biocompatable materials, polymeric drugs, immobilization of enzymes, cell-culture substratum and cancer chemotherapeutic agents (10-12). 

The effect of mixtures of surfactants and polyelectrolytes on spontaneous, water-catalysed hydrolysis (Fadnavis and Engberts, 1982) was mentioned in Section 4, but mixtures of functionalized polyelectrolytes and cationic surfacants are effective deacylating agents (Visser et al., 1983). Polymerized isocyanides were functionalized with an imidazole group and the deacylation of 2,4-dinitrophenyl acetate in the polyelectrolyte was speeded by addition of single or twin chain quaternary ammonium ion surfactants, up to a plateau value. Anionic surfactants had essentially no effect. It is probable that the cationic surfactants accelerate the reaction by increasing the deprotonation of the imidazole groups. 

Using NMP [114, 115] or reversible addition-fragmentation chain transfer (RAFT) [ 119,120,127], agents with ammonium groups for the ion exchange allowed the attachment of initiators on the clay surface for controlled radical polymerizations (NMP, RAFT). Samakande et al. investigated the kinetics of RAFT-mediated living polymerization of styrene [120] and styrene/BA [119] mixtures in miniemulsion. 

Induction periods of various lengths have been reported for anionic and cationic polymerizations of formaldehyde. It is apparent that the compound that is added as initiator is rarely the actual initiator. Tetraalkyl ammonium acetate used for the potymerization of formaldehyde is a slow initiator but capable of initiating formaldehyde polymerization. Methanol, other alcohols or water, always present in the polymerization mixture, are responsible for the high rates of polymerization. They act as efficient chain transfer agents and alkoxide or hydroxide ions are the actual initiators they initiate by a factor of several powers of ten more efficiently than acetate. 

The intercalation of PANI in zirconium phosphate (ZrP) was also reported by Chang et al. [69]. Different phases of zirconium phosphate, such as y-ZrP, the dihydrogen form of a-ZrP [o -ZrP(HH)], and o -ZrP(NaNa), were intercalated with aniline by either ion-exchange or adsorption, and then polymerized by oxidizing agents such as ammonium peroxydisulfate and iron (III) chloride. The resulting polyaniline nanocomposites showed measurable electrical conductivities, as listed in Table 6.3. 

Sihca impregnated with saturated and unsaturated hydrocarbons (squalene, paraffin oil) silicone and plant oils complexing agents (silver ions, boric acid, and borates carbohydrates unsaturated and aromatic compounds) chelating compounds [ethylene diamine tetra-acetic add (EDTA), digitonin] transition metal salt synthetic peptides 18-crown-6 and ammonium sulfate silanized sdica gel impregnated with anionic and cationic surfactants Cross-hnked, polymeric dextran gels (Sephadex)... 

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