Charge Density Effects on the Aggregation Properties of Poly(p-phenylene-ethynylene)-Based Anionic Polyelectrolytes

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• 作者：Mingyan Wu ; Palwinder Kaur ; Hongjun Yue ; A. M. Clemmens ; David. H. Waldeck ; Cuihua Xue ; Haiying Liu
• 刊名：Journal of Physical Chemistry B
• 出版年：2008
• 出版时间：March 20, 2008
• 年：2008
• 卷：112
• 期：11
• 页码：3300 - 3310
• 全文大小：405K
• 年卷期：v.112,no.11(March 20, 2008)
• ISSN：1520-5207

文摘

This work shows that low charge density poly(p-phenylene-ethynylene)s (PPE-SO₃Na-L and PPE-CO₂Na-L), which feature sulfonate and carboxylate groups on every other phenyl ring, form aggregates in water,whereas high charge density poly(p-phenylene-ethynylene)s (PPE-SO₃Na-H and PPE-CO₂Na-H), which possesssulfonate or carboxylate groups on every phenyl ring, do not aggregate in water. The formation of aggregatesof PPE-SO₃Na-L and PPE-CO₂Na-L is demonstrated by comparing the concentration and temperaturedependence of their steady-state spectra in water to that in DMSO, in which the two polymers do not aggregate.For the weak polyelectrolytes PPE-CO₂Na-H and PPE-CO₂Na-L, the solution pH was changed to vary thecharge density. In addition, the cationic surfactant, octadecyltrimethyl ammonium, is shown to dissociate thelow charge density polymer aggregates and to form supramolecular complexes with each of the differentpolyelectrolytes. Fluorescence correlation spectroscopy was applied to provide insight into the sizes ofaggregates under different solution conditions.