0000000000764524
AUTHOR
Jerome B. Lando
Polymeric amphiphiles with hydrophilic main chain spacers: Studies in monolayers and Langmuir-Blodgett multilayers
A methacrylic lipid was polymerized to form an amphiphilic homopolymer and random copolymers with various levels of acrylic acid comonomers. The behavior of these polymeric lipids was investigated in monolayers at the air-water interface and in Langmuir-Blodgett multilayers on polymer foil supports. The acrylic acid acts as a hydrophilic spacer along the polymer backbone, and improves the ability of the polymer to self-organize into highly ordered monolayers and ultimately LB multilayers. It is shown that the quality and stability of the multilayers increase substantially with the increase in comonomer content.
Time and Temperature Dependence of Macro-ion-Macro-ester Equilibrium in the Cationic Polymerization of Tetrahydrofuran by HOSO2F
Abstract Reactivity and equilibrium of two active species-tertiary oxonium ion (TOI) and superacid ester (SAE)-in the system of cationic polymerization of tetrahydrofuran (THF) initiated by fluorosulfonic acid (FSO3H) in dichloromethame has been studied. In the given system, it was found that TOI is mainly responsible for the polymerization at the initial stage; however, the cocentration of TOI decreases rapidly with the progress of polymerization and finally becomes almost untraceable. On the other hand, [SAE] monotonically increases as the polymerization proceeds. The stability of TOI appears less than that of SAE under the given reaction conditions. Results demonstrate that both the prog…
Polymerization of mono- and multilayer forming diacetylenes
Heptadeca-2,4-diine-1-ol and Heptadeca-2,4-diine-1-acid were synthesized and their polymerization behaviour in the solid state was investigated. Both compounds polymerize thermally below the melting point and photochemically under the action of uv-light to form polymers via 1,4-addition to the conjugated triple bonds with a backbone of conjugated double-and triple-bonds. The photoresponse spectra resemble the absorption spectra exhibiting maxima of photoreactivity in the absorption band of the conjugated triple bonds of the monomers.