Polymer groups cationic

Another reaction that has been applied to the generation of highly functionalized polymers is cationic polymerization [12-15]. Catalysts for cationic polymerizations are aprotic acids, protic acids, or stable carbocation salts. In these processes, the catalyst generally reacts with a cocatalyst to form an active initiated species. Initiation takes place by protonation of the monomer (Fig. 2A). Monomers that possess cation stabilizing groups, such as electron rich olefins, are preferred as they more readily undergo the desired polymerization process... 

Highly branched ethene-methyl acrylate polymers. The cationic palladium diimine complexes are remarkably tolerant towards functional groups, although the rates decrease somewhat when polar molecules are added. In ETM catalysis addition of polar molecules or monomers kills the catalyst and therefore it was very interesting to see what the new palladium catalysts would do in the presence of polar monomers. Indeed, using methyl acrylate a copolymerisation... 

Syntheses of Self-Sensitized Polymers by Cationic Copolymerizations. The cationic polymerizations of several vinyl ethers containing pendant ester groups such as cinnamic ester 12), methacrylic ester 16), acrylic ester (77), and crotonic ester 18) have been reported. Based on these reports, cationic copolymerizations of CEVE with photosensitizer monomers such as NPVE, NNVE, VNP and NPEVE were carried out using TFB as a catalyst in toluene at — 65 °C. Each copolymer was obtained with high yield except in the case of copolymerization of CEVE with VNP as summarized in Table I. 

Although there are some limitations on the molecular weights of the linear polymers which may be obtained by this method, AM polymerization offers an attractive, synthetic route for preparation of functional, medium molecular weight polymers by cationic polymerization of oxiranes. As the process involves the extension of the chain of hydroxyl group containing compound used to initiate the polymerization (initiator), the method is especially well suited for preparation of oligodiols (low molecular weight diols as initiators) and macromonomers (for example, hydroxy-ethyl acrylate as initiator) ... 

All the approaches described have been used to prepare functional polymers by cationic ring-opening polymerization. From this point of view, groups of monomers that have been investigated most are cyclic ethers (tetrahydrofuran), cyclic acetals (1,3-dioxolane), cyclic imines (N-f-butylaziridine), and oxazolines, i.e., these monomers for which the living conditions can be approached. 

As mentioned before, superabsobents should be essentially low crosslinked hydrophilic polymers and have ionic groups such as anionic groups, cationic groups, or betaine in the polymers. They usually have a high water-absorption capacity of more than 100 g-water/g-polymer even in dilute salt solution. In Fig. 2, swollen crosslinked poly (sodium acrylates) are illustrated. 

Antibacterial Ability of Superabsorbent Polymers Containing Cationic Groups ... 

Polyamide-6,6 fabrics were treatedusinganovel procedure employing ionic interactions between anionic carboxylic end groups of the polymer and cationic quaternary ammonium salts to produce fabrics with antimicrobial activity. The effects of the pH of the treatment bath, treatment temperature, treatment time and quaternary... 

Also, because ion exchange membranes have polar groups (cationic and/or anionic charge) in a non-polar polymer matrix, which is different from other polymer membranes, they have a particular microstructure. Knowledge of this microstructure is necessary to use the ion exchange membranes efficiently. Many studies on the microstructure have been performed both from an academic viewpoint and in terms of industrial requirements. Representative studies are described here. 

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