Regensburg 2007 – wissenschaftliches Programm
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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 8: POSTER: Polymer Physics
CPP 8.7: Poster
Montag, 26. März 2007, 16:00–18:00, Poster B
Chemical confinement: Additional modes in the relaxation spectrum of a copolymer — •Jörg Hachenberg1, Björn Steisel2, Dennis Bedorf1, Michael Buback2, and Konrad Samwer1 — 1I. Physikalisches Institut, Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany — 2Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, 37077 Göttingen, Germany
Copolymers with different monomer distributions but of comparable composition and comparable degree of polymerization have been investigated by mechanical spectroscopy and differential scanning calorimetry. An additional mode occurs in the relaxation spectra of copolymers with a non-random monomer distribution which is absent in those with a random distribution. This is interpreted as the motion of soft block-like segments between rigid segments in the non-random copolymer. These unique features can be found in poly(ethylene-co-methacrylic acid) (EMAA) synthesized by high pressure free radical polymerization under steady state conditions. Two hydrogen bonds can tighten the methacrylic acid functions forming a chemical confinement in samples with a non-random distribution. The sample properties are controlled by SEC, FTIR and NMR.
This work is supported by DFG, Graduiertenkolleg 782.