Self-organization of rod-coil molecules into nanoaggregates: A coarse grained model

Mehmet Sayar, Samuel I Stupp

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

Triblock rod-coil oligomers with bulky coil blocks were previously utilized to create self-organized mushroom-shaped nanoaggregates. The boundary effects in such small aggregates and the steric repulsions due to close packing of bulky coil blocks lead to highly perturbed, nonideal systems. We describe here a coarse grained model to understand the properties of such systems. This model is based on enumeration of chain conformations on a lattice to calculate entropy loss due to aggregation. We studied the contribution of chain architecture and crystallization enthalpy on equilibrium properties such as size, size distribution, and thermodynamic stability for a mushroom-shaped constrained structure. In agreement with previous theoretical work for other finite architectures, our study verified that aggregate size is determined by the competition between entropic and enthalpic contributions from different blocks. Most importantly, polydispersity of the nanoaggregates was found to decrease as bulkiness of the coil block structural unit is increased and also as surface energy of the rod block crystal is increased. These results suggest that branched coil architectures such as dendrons could be utilized to further improve the structural properties of the aggregates.

Original languageEnglish
Pages (from-to)7135-7139
Number of pages5
JournalMacromolecules
Volume34
Issue number20
DOIs
Publication statusPublished - Sep 25 2001

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Molecules
Dendrimers
Polydispersity
Crystallization
Oligomers
Interfacial energy
Conformations
Structural properties
Enthalpy
Thermodynamic stability
Entropy
Agglomeration
Crystals

ASJC Scopus subject areas

  • Materials Chemistry

Cite this

Self-organization of rod-coil molecules into nanoaggregates : A coarse grained model. / Sayar, Mehmet; Stupp, Samuel I.

In: Macromolecules, Vol. 34, No. 20, 25.09.2001, p. 7135-7139.

Research output: Contribution to journalArticle

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