Bulk Properties of Dendronized Polymers with Tailored End-groups emanating from the same Backbone
2005 (English)In: Journal of Polymer Science Part A: Polymer Chemistry, ISSN 0887-624X, E-ISSN 1099-0518, Vol. 43, no 19, 4496-4504 p.Article in journal (Refereed) Published
Dendronized polymers with a methacrylate backbone bearing pendant aliphatic polyester dendrons based on 2,2-bis(methylol)propionic acid have been investigated by rheological measurements, differential scanning calorimetry (DSC), size exclusion chromatography (SEC), and H-1 NMR self-diffusion techniques. The change in material properties due to the attachment of larger dendrons and/or different end-groups to a backbone of the same length is investigated. Dendronized polymers of the second to fourth generation with hydroxyl, acetonide, or hexadecyl end-group functionalities have been studied. DSC revealed that the glass transition temperature of the amorphous polymers increases with increasing size of the dendrons, and that the ability for the hexadecyl functional polymers to crystallize decreases with increasing size of dendrons. H-1 NMR self-diffusion and longitudinal relaxation data are consistent with an elongated rod-like model of the polymers in solution. Larger dendrons lead to a larger rod diameter that approximately double when increasing the generation of dendronized polymer from two to four. Rheological measurements demonstrated that the complex viscosity at low frequency increased with dendron size. Independently of the functionality, the second and third generation samples initially showed a Newtonian plateau, followed by a shear thinning region at higher frequencies. The fourth generation samples only showed shear thinning over the whole frequency region.
Place, publisher, year, edition, pages
2005. Vol. 43, no 19, 4496-4504 p.
dendronized polymer, size exclusion chromatography, 1H NMR self-diffusion, differential scanning calorimetry, rheology
IdentifiersURN: urn:nbn:se:kth:diva-5745DOI: 10.1002/pola.20918ISI: 000231989400018ScopusID: 2-s2.0-27744489363OAI: oai:DiVA.org:kth-5745DiVA: diva2:10218
QC 201009012006-05-172006-05-172010-12-16Bibliographically approved