Polystyrene carboxylate anions

Anionic polymerization of pivalolactone with the polystyrene anion produced only homopolymer mixtures, but the polystyrene carboxylate anion was able to give a block copolymer336. The block efficiency depends on catalyst ratio and conversion because the initiation step is slow compared with propagation337. Tough and elastic films were obtained by graft copolymerization or block copolymerization of pivalolactone onto elastomers containing tetrabutylammonium carboxylate groups338,339. ... 

In the proposed mechanism of hydrolysis (16), the carboxylate anion of 13-15 or acetyl Phe is recognized by the guanidinium ion, and the Cu(n) center subsequently hydrolyzes the amide group. Both the electrostatic interaction between carboxylate and guanidinium ions and the Cu(n)-catalyzed amide cleavage would be facilitated by the microenvironment provided by polystyrene. 

Horie et al.46 applied two fluorochromes (DNS and 6-p-toluidino-2-naphthalenesulfonate) to estimate the hydrophobicity of the microenvironment of cross-linked polystyrene containing quaternary ammonium groups. They found a correlation between the wavelength of the emission maximum of fluorophores and the rate of decarboxylation of 6-nitrobenzisoxazole-3-carboxylate anion catalyzed by these gels. The hydrophobic microenvironment due to cross-linked matrices was suggested as a cause for this catalytic activity.47... 

Further improvements were made by carboxylating the polystyrene anion, leading to quantitative yields39S 396. Multiblock copolymers of molecular weight 500,000 consisting of sixty segments of poly-THF and polystyrene were prepared397. The effect of the molar feed ratio of the two components is shown in Fig. 7. 

The polydispersity of polymers prepared in this way is usually very low for example, a value MJM of 1.05 was found for a sample of poly(a-methylsty-rene). Living polymers can also be used for the preparation of block copolymers after the consumption of the first monomer, a second anionically polymerizable monomer is added which then grows onto both ends of the initially formed block. By termination of the living polymer with electrophilic compounds the polymer chains can be provided with specific end groups for example, living polystyrene reacts with carbon dioxide to give polystyrene with carboxylic end groups. 

Solvent dyes [1] cannot be classified according to a specific chemical type of dyes. Solvent dyes can be found among the azo, disperse, anthraquinone, metal-complex, cationic, and phthalocyanine dyes. The only common characteristic is a chemical structure devoid of sulfonic and carboxylic groups, except for cationic dyes as salts with an organic base as anion. Solvent dyes are basically insoluble in water, but soluble in the different types of solvents. Organic dye salts represent an important type of solvent dyes. Solvent dyes also function as dyes for certain polymers, such as polyacrylonitrile, polystyrene, polymethacrylates, and polyester, in which they are soluble. Polyester dyes are principally disperse dyes (see Section 3.2). 

The first block (polybutadiene or polystyrene) is prepared by anionic polymerization, under high vacuum, in THF dilute solution (less than 5%), at low temperature (—70 °C) with cumylpotassium as initiator. Then, the living polymer is transformated into a hydroxylated polymer (PV—OH) by addition of ethylene oxide under vacuum, or into a carboxylated polymer (PV-COOH) by addition of carbon dioxide under vacuum. 

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