Quaternary ammonium cationic monomers

The cationic monomer can be a diallyldimethyl ammonium halide, a di-methylaminoethyl acrylate quaternary salt, or a dimethylaminoethyl methacrylate quaternary salt [1635]. The copolymers may be in solid, dispersion, latex, or solution form. 

Another mode of termination by monomer, which has been suggested for the polymerization of N-vinylcarbazole, is formation of a quaternary ammonium ion from the growing cation and the monomer [25] which is essentially the same as reaction (XIa). 

Free radical polymerizations may also be used to synthesize a host of cationic polyelectrolytes. Diallyl quaternary ammonium salts such as dimethyl-diallylammonium chloride, diallyldiethylammonium chloride, and diallylmethyl b-propionamido chloride are an interesting class of monomers which will... 

In another paper Fendler et al.59) investigated again the CMC dependence of alkylammonium propionates on the number of carbon atoms in the alkyl group of the quaternary ammonium cation (Fig. 12). The same feature as mentioned with octylammonium carboxylates is observed, i.e., the constancy of the CMC values for these alkylammonium propionates in carbon tetrachloride, while in benzene a linear plot is obtained. The latter is taken to indicate the decreased solubility of the monomers with increasing alkyl chain length in benzene. Table 471 exhibits in addition... 

To synthesize water-soluble or swellable copolymers, inverse heterophase polymerization processes are of special interest. The inverse macroemulsion polymerization is only reported for the copolymerization of two hydrophilic monomers. Hernandez-Barajas and Hunkeler [62] investigated the copolymerization of AAm with quaternary ammonium cationic monomers in the presence of block copoly-meric surfactants by batch and semi-batch inverse emulsion copolymerization. Glukhikh et al. [63] reported the copolymerization of AAm and methacrylic acid using an inverse emulsion system. Amphiphilic copolymers from inverse systems are also successfully obtained in microemulsion polymerization. For example, Vaskova et al. [64-66] copolymerized the hydrophilic AAm with more hydrophobic methyl methacrylate (MMA) or styrene in a water-in-oil microemulsion initiated by radical initiators with different solubilities in water. However, not only copolymer, but also homopolymer was formed. The total conversion of MMA was rather limited (<10%) and the composition of the copolymer was almost independent of the comonomer ratio. This was probably due to a constant molar ratio of the monomers in the water phase or at the interface as the possible locus of polymerization. Also, in the case of styrene copolymerizing with AAm, the molar fraction of AAm in homopolymer compared to copolymer is about 45-55 wt% [67], which is still too high for a meaningful technical application. 

Hernandez-Barajas J, Hunkeler DJ (1997) Inverse-emulsion copolymerization of acrylamide and quaternary ammonium cationic monomers with block copolymeric surfactants copolymer composition control using batch and semi-batch techniques. Polymer 38(2) 449—458... 

The surfactant may be cationic, or anionic, even nonionic. The type most used for MCM-41 and MCM-48 is cationic quaternary ammonium surfactant. The inorganic resources are those monomers or oligomers that are polymerizable or condensable under certain conditions (concentration, temperature, pressure, pH, solvent, etc.) and form inorganic solid matter such as gel, ceramic, and glass. The depolymerization or hydrolysis is necessary sometimes, for example with TEOS, Ti(OC2H5)4, silicon sol, sodium silicate, and amorphous silica. 

The Polymerization of Quaternary Ammonium Cationic Monomers with Acrylamide... 

Cationic polymers can be grouped in three categories ammonium (primary, secondary, tertiary, and quaternary) sulfonium and phosphonium compounds. Of these, the ammonium-based polymers have been the most popular, because phosphonium compounds have not been synthesized to high molecular weights (2-8), and sulfonium monomers are generally unstable and less readily available than quaternary ammonium monomers (9-i2). 

Poly(diallyldimethylammonium chloride) was the first quaternary ammonium polymer approved for potable water clarification by the United States Public Health Service, and has historically been the most widely produced cationic polyelectrolyte. There have been several studies on the kinetics (26-37) and uses of diallyldimethylammonium chloride (DADMAC) (38-45) however, there have been no investigations in inverse microsuspension, the most common industrial method of polymerization. Furthermore, there is considerable disagreement between published reactivity ratios, probably because no satisfactory analytical methods have been described in the literature for residual monomer concentration or copolymer composition. For other commercially important quaternary ammonium polymers, such as dimethylaminoethyl methacrylate and dimethylaminoethyl acrylate, few kinetic data are available (46-51) only Tanaka (37) measured the reactivity ratios. 

Analytical Methods. Historically, the copolymer composition of cationic acrylic polymers has been measured by conductiometric (28), silver nitrate (29), or colloid titration (52, 53). Chromatographic methods have been reported for acrylamide monomer (54-56) however, no such methods have been employed for quaternary ammonium monomers. In this chapter, a new HPLC method (Nalco) is described for the simultaneous determination of both comonomers. Colloid titration is described in the next paragraph and was used only for comparison purposes. 

In comparison to the previously discussed monomers, the polymerization of N-substituted aziridines is easier to control since the side reactions by proton transfer are eliminated because of the absence of primary and secondary amines. Nonetheless, termination by nucleophilic attack of the cationic propagating chain end into polymeric tertiary amines results in the formation of unreactive quaternary ammonium groups, that is, termination. As a result, the polymerization of N-substituted aziridines usually stops at limited conversion as was first demonstrated for A-methylaziridine by Jones [129]. Detailed evaluation of the polymerization kinetics as well as the evolution of molar mass during the polymerization revealed that termination mainly occurs via intramolecular backbiting... 

The cationic copolymerization was carried out in air at 25°C in a nitrobenzene solution using stannic bromide as catalyst, while the anionic polymerization was studied in air with sodium dissolved in anunonia [186]. Although many monomers may be polymerized by quaternary ammonium salts, vinyl acetate does not produce any polymer on treatment with dimethylphenylbenzylammonium chloride [187]. 

Dyed in wet spinning during wash stage or pigmented dope Blend of moisture absorbing and finedenier staple fibers Incorporate halogen monomers, such as vinylidene chloride and antimony compounds Cationic dye sites quaternary ammonium compounds... 

Similar to the biguanide structures, Dizman et al. created l,4-diazabicyclo[2.2.2]octane (DABCO)-based stmctures carrying two quaternary ammonium charges with butyl and hexyl alkyl extensions (C12). The monomer was assembled by multiple nucleophilic substitution reactions. Polymers were formed by free radical polymerization in water. These polymers, much like the biguanide acrylate and pyridinium polymers, combined hydrophobidty and cationic charge on the same monomer. One difference is that the cationic charge was also separated from the backbone of the polymer by a long alkyl chain. As with the pyridine polymers, the hexyl alkyl monomers were found to be the most effective biocides. 

Further work by Palermo and Kuroda extended the library of molecules to indude tertiary amine- and quaternary ammonium-fimctionalized methacrylates. For this series, cationic monomers were polymerized with methyl and butyl acrylate monomers. As with the styrene-based polymers of Gelman et al, the quaternary ammonium series was much less antimiaobial and somewhat less hemolytic than the primary and tertiary amine series. Again, titration of the polymers showed that there is partial deprotonation of the amine functionalities at neutral pH. The deprotonated moieties are more hydrophobic than the ammonium salts, and thus inaease the membrane activity of the polymers. No explanation was given, however, for the inaeased activity of the primary amine polymers over the tertiary amine polymers. 

Definition Polymeric quaternary ammonium salt consisting of acrylamide and dimethyl diallyl ammonium chloride monomers Formula (CsHieN C3H5NO Cl)x Properties Dens. 1.020 ref. index 1.350 (20 C) cationic... 

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