A Materials-Based Laboratory Exercise-Intercalation and Deintercalation of Dimethylsulfoxide and Poly(ethylene glycol) into Minerals

TCE

The Chemical Educator

ISSN: 1430-4171 (electronic version)

Table of Contents

Abstract Volume 11 Issue 5 (2006) pp 319-322

A Materials-Based Laboratory Exercise—Intercalation and Deintercalation of Dimethylsulfoxide and Poly(ethylene glycol) into Minerals

Elizabeth Baker, Cassandra Dyal, Beverly Harris, Jessica Miller, Jessica Moore, Will E. Lynch, and Delana A. Nivens*

Department of Chemistry and Physics, Armstrong Atlantic State University, Savannah, Georgia 31419, nivensde@mail.armstrong.edu
Received December 28, 2006. Accepted June 16, 2006.

Published online: 9 August 2006

Abstract. The intercalation of organic compounds and polymers into common minerals and the chemical analysis of the resulting composite can easily be performed by students in a variety of laboratory courses including materials chemistry, inorganic chemistry, physical chemistry, and instrumental analysis. This exercise introduces students to minerals and their structural framework as well as the utility of these materials to act as effective templates for chemistry. The intercalation of these compounds can serve as models for the preparation of nanocomposite materials where the mineral acts as “host” to the organic substrate. In this experiment, bentonite (BENT) and kaolinite (KAO) were intercalated with dimethylsulfoxide (DMSO) and poly(ethylene glycol) (PEG-5000). Analyses were performed using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS). These analyses are used to verify intercalation and determine the extent of the substrates contained in the minerals. In this example DMSO and PEG-5000 are found to be successfully intercalated into bentonite and kaolinite. Further, information regarding the amount of substrate absorbed into BENT and KAO as a function of mineral mass can be determined as well as the relative energetics associated with the interactions. Presented are inorganic chemistry student results with corresponding statistical analysis.

Key Words: Laboratories and Demonstrations; materials chemistry; inorganic chemistry; physical chemistry; instrumental analysis; spectroscopy

(*) Corresponding author. (E-mail: nivensde@mail.armstrong.edu)

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