Understanding Self-Segregation of Immiscible Peripheral Segments in Pseudodendritic Hyperbranched Polydithioacetals: Formation of Improved Janus Structures

Chatterjee, Saptarshi and Ramakrishnan, S (2014) Understanding Self-Segregation of Immiscible Peripheral Segments in Pseudodendritic Hyperbranched Polydithioacetals: Formation of Improved Janus Structures. In: ACS MACRO LETTERS, 3 (9). pp. 953-957.

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Abstract

Peripherally heterofunctionalized hyperbranched polymers (HBPs) undergo immiscibility-driven self-segregation of the outer segments to form Janus molecular entities (Macromolecules 2012, 45, 2348). In HBPs prepared via AB2 type self-condensation, single-step peripheral heterofunctionalization would lead to random distribution of the two types of terminal units, namely, homofunctionalized (homo-T) and heterofunctionalized (hetero-T) termini. Here, we examine the role of such hetero-T units on the self-segregation of heterofunctionalized pseudodendritic hyperbranched polydithioacetals. Three different heterofunctionalized HB dithioacetals bearing roughly 50 mol % each of docsyl (C-22) and MPEG-350 chains at the periphery were prepared: one of them carried a statistical distribution of homo-T and hetero-T units, and the other carried only two types of homo-T (-TR1R1 and -TR2R2) termini, whereas the third carried largely hetero-T (-TR1R2) termini. Careful examination of DSC and SAXS data reveals that the self-segregation is most effective in HBPs devoid of hetero-T units; interestingly, however, it also showed that randomly heterofunctionalized HBPs self-segregated nearly as effectively.

Item Type:	Journal Article
Publication:	ACS MACRO LETTERS
Publisher:	AMER CHEMICAL SOC
Additional Information:	Copyright for this article belongs to the AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA.
Department/Centre:	Division of Chemical Sciences > Inorganic & Physical Chemistry
Date Deposited:	08 Nov 2014 05:08
Last Modified:	08 Nov 2014 05:08
URI:	http://eprints.iisc.ac.in/id/eprint/50165

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