TY  - JOUR
AU  - Staropoli, Mariapaola
AU  - Raba, Andreas
AU  - Hövelmann, Claas H.
AU  - Appavou, Marie-Sousai
AU  - Allgaier, Jürgen
AU  - Krutyeva, Margarita
AU  - Pyckhout-Hintzen, Wim
AU  - Wischnewski, Andreas
AU  - Richter, Dieter
TI  - Melt dynamics of supramolecular comb polymers: Viscoelastic and dielectric response
JO  - Journal of rheology
VL  - 61
IS  - 6
SN  - 1520-8516
CY  - Melville, NY [u.a.]
PB  - Inst.
M1  - FZJ-2017-07364
SP  - 1185 - 1196
PY  - 2017
AB  - The structure and the dynamics of supramolecular comblike polymers in the melt state is studied by a combination of linear rheology, dielectric spectroscopy, and small angle neutron scattering. The system consists of blends of 1,2-polybutyleneoxide (PBO) entangled backbones, randomly functionalized with thymine (thy) and barely entangled PBO graft chains—modified with 2,4-diamino-1,3,5-triazine (DAT) end groups. These bioinspired groups associate into a transiently branched comb architecture through heterocomplementary interaction involving the two different hydrogen bonding groups thy and DAT. In the present manuscript, we focus on the comparison of the macroscopic dynamics of the associating blends and permanent comb analogs. The viscoelastic and dielectric response of covalent and reversible combs are found to be comparable. The viscoelastic response of mixtures of thy-functionalized entangled backbones and DAT-end-modified barely entangled chains show a relaxation mechanism, which is mostly attributed to the association/breakage dynamics of the transient bonds with characteristic time ∼1 s  at T=−25 °C. In the parallel dielectric investigation, the reversible branched structure is still evident from the comparison with the corresponding permanent combs and allows the distinction between fixed arms relaxation and the lifetime. A α∗  process of the thy-thy association is likewise detected. The time scale of the supramolecular association makes the thy-DAT pair an ideal candidate for the development of responsive materials that combine permanent and transient linkages for novel applications and self-healing properties
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000414273200012
DO  - DOI:10.1122/1.5001059
UR  - https://juser.fz-juelich.de/record/838854
ER  -