Nanocomposites Based on Coil-Comb Diblock Copolymers

Autor:	Aaron Hall, Ivan Jayapurna, Valeriy V. Ginzburg, Jingyu Huang, Ting Xu, Samana Algharbi
Rok vydání:	2021
Předmět:	chemistry.chemical_classification Nanocomposite Materials science Polymers and Plastics Organic Chemistry Chain transfer Polymer Inorganic Chemistry chemistry.chemical_compound Chemical engineering chemistry Polymerization Phase (matter) Materials Chemistry Copolymer Lamellar structure Polystyrene
Zdroj:	Macromolecules. 54:1006-1016
ISSN:	1520-5835 0024-9297
DOI:	10.1021/acs.macromol.0c02441
Popis:	The polymer chain architecture is an important factor determining the phase behavior of nanoparticle (NP) assembly in polymer matrices. Block copolymers (BCPs) containing a random copolymer (RCP) block present a convenient variation on traditional BCPs to tune the interaction parameters between the polymer blocks and the nanofillers as well as to evaluate the effect of the chain architecture on the NP arrangements within BCP microdomains. Here, we synthesized BCPs with a coil polystyrene (PS) block and a comb RCP block through reversible addition-fragmentation chain transfer polymerization. The RCP block consists of methyl- and lauryl acrylates, the latter of which confers a long-chain alkyl moiety to favorably interact with alkyl-passivated NPs. BCPs showing lamellar, cylindrical, and mixed morphologies were obtained by varying the volume fractions of the RCP block (fRCP). In comparison to coil-coil BCP, the coil-comb BCPs show highly asymmetric phase behavior with respect to fRCP, where lamellar morphologies were observed at fRCP from 0.31 to 0.51. NPs in the size of 4–5 nm were successfully incorporated in the RCP block of the BCPs with periodicities of 30–60 nm. An order-to-order phase transition from lamellae to PS cylinders was observed after the addition of only 1–2 vol % 5 nm NPs into the BCP with a periodicity of 25 nm and fRCP of 0.51. Self-consistent field theory-density functional theory simulations qualitatively described the observed morphologies and phase transitions in the nanocomposites. The current study presents a platform to fabricate nanocomposites with NP assemblies in coil-comb BCPs that contain a random copolymer block and provides insight into how polymer chain architectures can affect the phase behavior of BCPs and nanocomposites.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::b3223ac24aed4d41528162d367fb6ca8 https://doi.org/10.1021/acs.macromol.0c02441 Zobrazit plný text záznamu