SYNTHESIS OF NEW BLOCK COPOLYMERS BASED ON POLYETHYLENGLYCOL AND 2-OXAZOLINES

• Autores: Rueda, Juan, Asmad, Miguel, Sedano, Marisol, Zschoche, Stefan, Voit, Brigitte
• Formato: artículo
• Fecha de Publicación: 2015
• Institución: Sociedad Química del Perú
• Repositorio: Revista de la Sociedad Química del Perú
• Lenguaje: español
• OAI Identifier: oai:rsqp.revistas.sqperu.org.pe:article/33
• Enlace del recurso: http://revistas.sqperu.org.pe/index.php/revistasqperu/article/view/33
• Nivel de acceso: acceso abierto
• Materia: copolymers; poly(ethylenglycol); poly(2-oxazolines); Copolímeros; poli(etilenglicol); poli(2-oxazolinas)

New block copolymers (typ AB) were obtained by the ring opening cationic polymerization of2-cyclopropyl- and 2-methoxycarbonylethyl-2-oxazoline, using tosylated polyethylenglycolas initiator. In block copolymers, the polymerization grade of polyethylenglycol (PEG)segment was always 45 units and of the poly(2-oxazolines) segment was variable, between33 to 242 units. The block copolymers, containing 2-methoxycarbonylethyl-2-oxazoline,were submitted to a quantitative hydrólisis of ester groups to obtain carboxylic acid units.The copolymers were characterized structurally by nuclear magnetic resonance spectroscopyand they show a conformational transition (LCST) between 24 and 48°C, which was functionof the polymer structure, of its content of cyclopropyloxazoline and carboxilic acid groups.