کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5184906 1381061 2009 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Isothermal titration calorimetry, transmission electron microscopy, and field emission scanning electron microscopy of a main-chain viologen polymer containing bromide as counterions
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Isothermal titration calorimetry, transmission electron microscopy, and field emission scanning electron microscopy of a main-chain viologen polymer containing bromide as counterions
چکیده انگلیسی

The interaction of a main-chain viologen polymer containing bromide as counterions with water and aqueous potassium bromide over a broad range of concentrations was studied with isothermal titration calorimetry. The dilution process of this polymer was endothermic as opposed to flexible poly(sodium acrylate) and poly(sodium styrenesulfonate). This result may be related to the different mechanism of hydration of pyridinium and bromide groups in the main chain. It also exhibited aggregation phenomenon in both water and aqueous potassium bromide solutions as detected by transmission electron microscopy like other flexible and rigid-rod polyelectrolytes. As the polymer concentrations in aqueous solutions increase, the aggregated polymer exhibited more defined ordered structures than random structures observed at low polymer concentrations. Field emission scanning electron microscopy also revealed the effect of variation of concentration of aqueous potassium bromide on the morphology of the polymer matrix. At increasing concentrations of aqueous potassium bromide, the polymer structures became more ordered than those in low concentrations.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 50, Issue 11, 22 May 2009, Pages 2393-2401
نویسندگان
, , , , , , ,