Year: 2017
Type: article
Abstract: Microphase separation in random multiblock copolymers is studied with the mean-field theory assuming that long blocks of a copolymer are strongly segregated, whereas short blocks are able to penetrate into “alien” domains and exchange between the domains and interfacial layer. A bidisperse copolymer with blocks of only two sizes (long and short) is considered as a model of multiblock copolymers with high polydispersity in the block size. Short blocks of the copolymer play an important role in the microphase separation. First, their penetration into the “alien” domains leads to the formation of joint long blocks in their own domains. Second, short blocks localized at the interface considerably change the interfacial tension. The possibility of penetration of short blocks into the “alien” domains is controlled by the product χNsh (χ is the Flory-Huggins interaction parameter and Nsh is the short block length). At not very large χNsh, the domain size is larger than that for a regular copolymer consisting of the same long blocks as in the considered random copolymer. At a fixed mean block size, the domain size grows with an increase in the block size dispersity, the rate of the growth being dependent of the more detailed parameters of the block size distribution.
Source: The Journal of Chemical Physics
DOI: 10.1063/1.4973933
Authors: E. N. Govorun, A. V. Chertovich
Institution: Lomonosov Moscow State University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Funder: Russian Science Foundation
Award: G5950500214
OpenAlex ID: W2579468554