Copolymers, comb shape properties

In the next section, therefore, we review recent studies of simpler cases, i.e., homopoly(macromonomers), star- and comb-shaped polymers, followed by some interesting properties of the graft copolymers to be used as polymeric surfactants, surface modifiers, and compatibilizers for blends. 

Compared to block copolymers, there have been relatively fewer examples of using homopolymers for nanofabrication. Nevertheless, some polymers with amphiphilic properties were also used in the fabrication of nanostructures with various metal salts/complexes. For example, polyaniline (PANI) emeraldine base formed self-organized mesomorphic structures when mixed with Zn(DBS)2 by the coordination between Zn2+ and the imine nitrogen atoms on the polymer main chain.100 The resulting supramolecule PANI[Zn(DBS)2]0.5 had a comb-shaped... 

The copolymerization of the macromonomers produced comb-shaped copolymers but their solution and solid state properties were similar to those of miktoarm stars. The number of PS and PI arms incorporated in the final product... 

The sensitivity of vibrational spectroscopy allows interactions of polyelectrolytes and surfactants to be monitored in aqueous and nonaqueous solutions. The solubilization and conformational properties of a comb-shaped copolymer of 1-octadecane-co-maleic anhydride in aqueous solution in the presence and absence of SDS depend on the degree of ionization of the copolymer (2i). The C-H stretching region of the Raman spectrum is sensitive to such interactions. Figure 11 illustrates how the C-H stretching band shifts as a function of solvent (in this case water and heptane). 

A copolymer of polyethylene glycol and maleic anhydride with a comb-shaped form, activated PM, was developed by NOF Corp. (Nippon Oil and Fats Co., Tokyo, Japan) [37]. Two activated PM copolymers have been prepared (Fig. 3i) activated PM13 (MW 13,000, m = 8, rt 33, R = H) and activated PMioo (MW 100,000, m 50, n 40, R = CH3). Amino groups in a protein molecule are coupled with maleic anhydride residues in the PM modifier to form acid-amide bonds (Scheme 7). These comb-shaped modifiers possess unique properties covering a protein molecule with the reaction between amino groups in a protein and multivalent acid anhydrides in the modifier. 

Two types of well defined branched polymers are acessible anionically star-shaped polymers and comb-like polymers87 88). Such macromolecules are used to investigate the effect of branching on the properties, 4n solution as well as in the the bulk. Starshaped macromolecules contain a known number of identical chains which are linked at one end to a central nodule. The size of the latter should be small with respect to the overall molecular dimensions. Comb-like polymers comprise a linear backbone of given length fitted with a known number of randomly distributed branches of well defined size. They are similar to graft copolymers, except that backbone and branches are of identical chemical nature and do not exhibit repulsions. 

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