Accession Number:

AD1071100

Title:

Chirality Transfer to Mesoscale Networks Assemblies

Descriptive Note:

Technical Report,29 Sep 2015,28 May 2018

Corporate Author:

University of Massachusetts Amherst United States

Personal Author(s):

Report Date:

2019-03-14

Pagination or Media Count:

13.0

Abstract:

Motivated by ongoing experimental studies by IANTP collaborator, Rong-Ming HoNatl Tsing Hua Univ., Taiwan, on the self-assembly ABC triblock copolymers possessing anintrinsically chiral block, an orientational self-consistent fieldoSCF theory framework was developed and used to study chiral organization of chain segments within self-assembled periodic, triblock nanostructures. This oSCF theory was applied to understand how the relationship between mesochiral geometry of the domain shapes and distribution and magnitude of inter-segment twist within chiral domains, within two distinct types of mesochiral geometries. First, non-cubic variants of the alternating gyroid morphology were investigated to determine how they exhibit variable degrees of intra-domain segment twist, which suggests a new mechanism to stabilize non-cubic network morphologies in chiral triblocks. Additionally, a recently developed analysis of electron tomography reconstructions from the Ho group was applied to quantify the mesoscale handedness of the alternating gyroid network phase formed by assemblies chiral triblock copolymers for the first time. Third, two classes diblock copolymers with type different types of chiral chain chemistry, but that both form the same chiral mesodomain morphology, were compared related to the predictions of the mean-field oSCF framework. Finally, motivated by recent experimental observations of complex, Frank Kasper FK phases in melts of conformationally asymmetric block copolymers by Bates and coworkers, a new computational framework to investigate the diblock foam model DFM of optimal spherical domain superlattices was developed.

Subject Categories:

  • Polymer Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE