Ampholytic polymer

Note An ampholytic polymer in which ionic groups of opposite sign are incorporated into the same pendant groups is called, depending on the structure of the pendant groups, a zwitterionic polymer, polymeric inner salt, or poly betaine. 

Ampholytic polymer in which pendant groups have a betaine-type structure. 

Ampholytic polymer containing ionic groups of opposite sign, commonly on the same pendant groups. 

ZIL monomers, having both cation and anion in the same monomer unit, were prepared in order to give different types of ampholyte polymers. Figure 30.4 shows the structure of the monomers used here [6]. Four different monomers were synthesized to study the relation between structure and such properties as ionic conductivity and Tg. 

Another class of complex forming polymers are the polyampholytes. Ampholytic polymers are those that contain both anionic and cationic substituents in their backbones. These charged groups may belong to different repeating units, or an inner salt may be formed in which the pendant group contains both cationic and anionic substituents. 

Table 7 lists in four categories some of the linear polymers which can be cross-linked to form hydrogels nonionic, anionic, cationic, and ampholytic linear poly-... 

Amphiphile-oil-water system, temperature of, 16 424-426 Amphiphiles, 16 420 Amphiphile strength, 6 424 Amphiphilic chemicals, 17 56 Amphiphilic copolymers, 20 482 behavior of, 20 483 well-defined, 20 485-490 Amphiphilic molecules, 15 99-101 Amphiphilic plasticizers, 14 480 Amphiphilic polymer blend, 23 720 Amphiphilic polymers statistical, 20 484-490 stimuli-responsive, 20 482-483 Ampholytes, 9 746-747 Amphoteric cyclocopolymers, water-soluble, 23 721 Amphoteric starches, 4 722 Amphoteric (zwitterionic) surfactants, 24 148... 

Prior to injection, the prepared sample should be centrifuged for 2 to 3 min in a microcentrifuge to remove any particulate material and to degas the solution. This practice is particularly important if the sample contains protein aggregates or other large particles, and when polymers are used to increase the viscosity of sample and ampholyte solution. 

CIEF analysis of rtPA in the presence of urea was also carried out in an uncoated capillary using pressure mobilization.114 The final urea concentration used was 4 M, and EOF was reduced by adding polymers to the reagents and sample (0.4% hydroxypropylmethyl cellulose produced better results than polyethylene glycol). A one-step CIEF method described by Moorhouse et al.115 for the analysis of rtPA produced a constant residual EOF in a neutral capillary. The sample was prepared by dilution to 125 to 250 pg of protein per milliliter in 3% ampholytes 3 to 10 and 5 to 8 (1 1) containing 7.5% TEMED and 4 M urea. Results obtained by CIEF correlated well with those generated by IEF, and the analysis was completed in less than 10 min. 

Ampholyte-type polymers should become attractive materials once successive and effective ion conductive paths are successfiiUy designed in the matrix. 

Yoshioka H, Mikami M, Mori Y, Tsuchida E (1993) Preparation of thermoresponsive surfaces using polyvinylchloride-graft-poly(A-isopropylacrylamide). Polym Adv Technol 4 519-521 Yu H, Grainger DW (1993) Thermosensitive swelling behavior in cross.linked N-isopropylacry-lamide networks-cationic, anionic, and ampholytic hydrogels. J Appl Polym Sci 49 1553-1563... 

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