Περίληψη:
Anionic polymerization techniques along with functional initiation and/or functional termination reactions were employed for the synthesis of end-functionalized polymers composed from polystyrene (PS), polyisoprene-1,4 (PI), and polybutadiene-1,4 (PBd) chains bearing –OH end groups. Specifically, PS-OH, HO-PS-OH homopolymers, PS-b-PI-OH and PI-b-PS-OH block copolymers, HO-PS-b-PI-b-PS-OH triblock copolymers, and PS(PBd-OH)2 miktoarm star copolymers were prepared. The –OH functions were transformed into 2–ureido–4–pyrimidone, UPy, groups leading to the synthesis of the corresponding functionalized polymers. The UPy groups interact through the formation of strong hydrogen bonds. The aggregation behavior of selected samples was studied by a variety of techniques, such as size exclusion chromatography, dilute solution viscometry, dynamic light scattering, differential scanning calorimetry, thermogravimetric analysis, melt rheology, small angle X-ray scattering, and atomic force microscopy. It was found that in the solid state and in non-polar solvents, the UPy-terminated chains associate leading to the formation of dimers and larger aggregates. This systematic study presents a library of useful materials for potential applications and for fundamental studies linking associations, molecular structure, and macroscopic properties. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
Συγγραφείς:
Bitsi, S.-L.
Stogiou, M.
Costanzo, S.
Stiakakis, E.
Vlassopoulos, D.
Nika, A.
Chatzichristidi, M.
Pitsikalis, M.
Λέξεις-κλειδιά:
Anionic polymerization; Block copolymers; Differential scanning calorimetry; Dimers; Hydrogen bonds; Light scattering; Polybutadienes; Size exclusion chromatography; X ray scattering, Aggregation behavior; Dilute-solution viscometry; End-functionalized polymers; Functionalized polymers; Macroscopic properties; Miktoarm star copolymers; Synthesis and characterizations; Termination reactions, Thermogravimetric analysis, 1,3 butadiene; copolymer; ethylene derivative; ethylene oxide; isoprene; polymer; polystyrene derivative; pyrimidine derivative, Article; atomic force microscopy; chemical structure; comparative study; controlled study; deprotection reaction; differential scanning calorimetry; hydrogen bond; molecular weight; photon correlation spectroscopy; polymerization; priority journal; room temperature; size exclusion chromatography; synthesis; thermogravimetry; viscometry; X ray crystallography
