TY  - JOUR
AU  - Baeza, Guilhem P.
AU  - Sharma, Ashwinikumar
AU  - Louhichi, Ameur
AU  - Imperiali, Luna
AU  - Appel, Wilco P. J.
AU  - Fitié, Carel F. C.
AU  - Lettinga, M.P.
AU  - Van Ruymbeke, Evelyne
AU  - Vlassopoulos, Dimitris
TI  - Multiscale organization of thermoplastic elastomers with varying content of hard segments
JO  - Polymer
VL  - 107
SN  - 0032-3861
CY  - Oxford
PB  - Elsevier Science
M1  - FZJ-2016-07614
SP  - 89 - 101
PY  - 2016
AB  - Thermoplastic elastomers (TPEs) based on segmented block-copolymers containing poly(tetrahydrofuran) (pTHF) and terephthalate-based diamide groups (T4T) were synthesized via polycondensation. While pTHF is known to be flexible and amorphous at rest, the more rigid T4T crystallized in different ways depending on both chain composition and sample preparation conditions. Increasing the content of hard-segments (HS) from 5 to 20% in weight leads to a substantial increase of the melting point Tm by more than 60 °C. We have systematically investigated the multiscale (1 Å - 50 nm) organization of the HSs (of fractions from 5% to 20%) by means of DSC, WAXS and (ultra) small angle X-ray scattering (U)SAXS. By increasing HS content, hence the rigidity of the chain, scattering experiments unambiguously show the formation of bigger and better defined ribbon-like crystallites, as well as the densification of the network they form. We propose a scenario for rationalizing the local T4T-HSs packing and the crystallites anisotropy at the mesoscale (1–10 nm) for HS fraction above 5%. Moreover, following in-situ the crystallization of TPEs with large HS fraction (20%), we highlight the presence of “persistent aggregates” present at T > Tm and study the ribbon-like crystallites growth mechanism during cooling from the melt state.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000389765500011
DO  - DOI:10.1016/j.polymer.2016.11.010
UR  - https://juser.fz-juelich.de/record/825137
ER  -