LANGMUIR AND LANGMUIR-BLODGETT-FILMS OF DERIVATIVES OF ALTERNATING COPOLYMERS OF STRAIGHT-CHAIN ALPHA-OLEFINS AND MALEIC-ANHYDRIDE

A series of alternating copolymers of straight-chain alpha-olefins and maleic anhydride were synthesized (M(n)BAR = 2500-37 000) and derivatives prepared by reaction of the anhydride residues with methanol and, in some cases, other alcohols, water, ammonia, and dimethylamine. Isotherms were measured for monolayers of the various polymer derivatives on water, and Langmuir-Blodgett (LB) multilayers were prepared. The majority of the polymers gave excellent isotherms (steep, high-collapse pressures) and, as determined by the detection of Bragg peaks by X-ray diffraction, Y-type LB films with a regular layer structure. Best results were obtained for polymers with a lipophilic side chain (derived from the alpha-olefin) containing 13-16 carbon atoms and with the two head groups as a carboxylic acid plus either carbomethoxy (or other small carboalkoxy group), carboxylic acid, or carboxamide. The LB films of these polymers were close packed, and, as judged from layer thicknesses and an infrared study, the lipophilic side chains were on average tilted at an angle of ca. 40-degrees. The in situ hydrolysis of one anhydride polymer on the water surface was investigated.