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Hydrophilic poly anionic surface

Specific properties of polysilanes have been linked to the method of synthesis.35 For example, in the case of anionic polymerization of poly[l-(6-methoxy-hexyl)-l,2,3-trimethyldisilanylene] a new type of chromism was induced in the polysilane film by the difference in the surface properties of substrates and was termed a surface-mediated chromism. The polysilane exhibited thermochromism with an absorption maximum at 306 nm at 23°C, but <15°C a band at 328 nm began to appear. A monolayer of the polysilane was transferred onto both a clean hydrophilic quartz plate and a hydrophobic one treated with hexamethyldisilazane by the vertical dipping method. With the hydrophobic plate, a broad UV absorption at 306 nm is obtained, whereas the absorption on a hydrophilic plate shifts to 322 nm. The conformation of the polysilane is preserved by hydrogen bonding between the silica surface and the ether section of the substituent on the hydrophilic plate. The polysilane is attached to the hydrophobic surface only by van der Waals forces, and this weaker interaction would not sustain the thermodynamically unstable conformational state that is attained on the water surface. [Pg.224]

The anionic block copolymerization of methyl methacrylate and glycidyl methacrylate leads to very versatile surface-active agents. The hydrophilic/hydrophobic balance of these amphipatic macromolecules can be easily controlled not only by the relative length of the constitutive blocks but also by the chemical modification of the epoxy groups. The poly(glycidyl methacrylate) block can be easily sulfo-... [Pg.54]


See other pages where Hydrophilic poly anionic surface is mentioned: [Pg.40]    [Pg.111]    [Pg.184]    [Pg.251]    [Pg.191]    [Pg.191]    [Pg.443]    [Pg.175]    [Pg.664]    [Pg.349]    [Pg.205]    [Pg.109]    [Pg.294]    [Pg.696]    [Pg.696]    [Pg.1184]    [Pg.415]    [Pg.422]    [Pg.797]    [Pg.440]    [Pg.642]    [Pg.142]    [Pg.174]    [Pg.284]    [Pg.518]    [Pg.184]    [Pg.95]    [Pg.492]    [Pg.2171]    [Pg.90]    [Pg.66]    [Pg.42]    [Pg.95]    [Pg.640]    [Pg.262]    [Pg.125]    [Pg.568]    [Pg.131]    [Pg.161]    [Pg.125]    [Pg.175]    [Pg.262]    [Pg.403]    [Pg.209]    [Pg.468]    [Pg.473]    [Pg.116]    [Pg.131]    [Pg.41]   
See also in sourсe #XX -- [ Pg.127 ]




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Anions, poly

Hydrophilic poly

Hydrophilic surfaces

Poly , surface

Surface hydrophilicity

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