Comparison of Gel Relaxation Times and End-Block Pullout Times in ABA Triblock Copolymer Networks

Peters, AJ; Lodge, TP

HERO ID

4707510

Reference Type

Journal Article

Year

2016

HERO ID 4707510
In Press No
Year 2016
Title Comparison of Gel Relaxation Times and End-Block Pullout Times in ABA Triblock Copolymer Networks
Authors Peters, AJ; Lodge, TP
Journal Macromolecules
Volume 49
Issue 19
Page Numbers 7340-7349
Abstract The gel relaxation times of two different poly[styrene-b-(ethylene-altpropylene)-b-styrene] (SEPS) ABA triblock copolymers in squalane at various concentrations has been measured by Theology. These relaxation times were compared with the results of previous time-resolved small-angle neutron scattering (TR-SANS) experiments, which measured chain exchange kinetics in SEP diblock and SEPS triblock micelles in squalane. The gels relaxed up to four orders of magnitude faster than expected based on the chain exchange measurements of equivalent diblock polymers. By accounting for two factors a bias toward shorter end-block lengths in the gel relaxation, and a reduction in the energy barrier to chain pullout caused by the triblock architecture a model is constructed that reconciles the surprisingly short gel relaxation times with the chain exchange times measured via TR-SANS.
Doi 10.1021/acs.macromol.6b01921
Wosid WOS:000385335800024
Is Certified Translation No
Dupe Override No
Is Public Yes