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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 64: Nanostructures, Nanostructuring and Nanosized Soft Matter II
CPP 64.2: Talk
Thursday, March 15, 2018, 09:45–10:00, PC 203
Homopolymer and Diblock Copolymer Blends with ABC Miktoarm Terpolymers — •Matthias M.L. Arras1, Hyeyoung Kim2, Monojoy Goswami1, Hong Kunlun1, Bobby G. Sumpter1, Thomas P. Russell2,3, and Gregory S. Smith1 — 1Oak Ridge National Lab, Oak Ridge, USA — 2University of Massachusetts Amherst — 3Lawrence Berkeley National Lab, Berkeley, USA
The effect of chain configuration in AB/ABC blends is investigated by small angle neutron scattering, transmission electron microscopy and molecular dynamics simulation. Here, the strongly segregating and asymmetric miktoarm star terpolymer poly(styrene)-arm-poly(isoprene)-arm-poly(2-vinylpyridine), where P2VP is the major component, was blended with equal volume fractions of either a PS/PI homopolymer mixture or an PS-b-PI diblock copolymer. We find that, depending on volume fraction, configuration and molar mass of the blended polymers, the morphology of the miktoarm star terpolymer is affected in various ways. In particular, swelling, improved ordering, or order-to-order transitions (OOT) were found. For low molar mass homopolymer blends (∼ 1/4 of the miktoarm block’s mass) we find examples where the ordering of the blend has improved over the pristine miktoarm star. An OOT from a lamellar to hexagonal phase is induced by the diblock copolymer blend when its molar mass is similar to the one of the miktoarm blocks.
This research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by ORNL. HK & TR were supported by AFOSR (16RT1602) and ARO (W911NF-17-1-0003).