Blends of polymers with electrolytes are crucial materials in the fabrication of synthetic membranes, imaging systems, and magnetic recording media. In recent work, we have focused on polymers blended with a particular type of ionic material, so-called ionic liquids. Unlike their high melting inorganic counterparts (e.g., table salt), ionic liquids melt at temperatures below 100˚C.Although they have intriguing and potentially very useful properties, ionic liquids are very expensive materials and many are toxic. However, two high melting point, cheap, non-hazardous, bulk commodity agricultural chemicals, choline chloride (vitamin B4) and urea, form a room temperature, deep eutectic ionic liquid when mixed in appropriate proportions. Polyacrylamide has similar functional groups to urea and we found that a miscible blend of this polymer with choline chloride can be formed. This unusual melting behavior is a consequence of the interactions between the components of the mixture. Infrared spectroscopy indicates that this is due to hydrogen bonding, as the three bands in urea assigned to amine and carbonyl groups are reduced to a doublet upon complex formation. Polyacrylamide/choline chloride spectra are similar to urea/choline chloride spectra. The nature of these interactions is being studied using infrared spectroscopy, and modeling, the latter work in collaboration with Professor Coray Colina. The development of cheap, non-toxic IL/polymer blends would be important step in producing useful devices.

Studies of Hydrogen Bonding Interactions in Deep Eutectic Choline Chloride/Polymer Blends

Paul Painter, Pennsylvania State Univ University Park, DMR 0901180

Infrared spectra of urea compared to the spectra of choline chloride/urea mixtures and polyacrylamide/choline chloride blends.

Broader Impacts – Education InitiativesPaul Painter, Pennsylvania State Univ University Park, DMR 0901180

In terms of broad impacts, we have over the years focused on creating educational content, writing textbooks and creating CDs containing numerous animations, thanks to the support of the NSF. Over the last two years we have made an effort to use these educational materials (text, figures, animations, etc.) to construct an on-line textbook using open-source software (Drupal). Textbooks are becoming very expensive and the goal of this effort is to make available learning material that can be viewed on-line using tablet computers and similar devices. However, this approach proved to be complex and time consuming. A much more flexible and interesting approach has been allowed by the recent introduction of iAuthor by Apple, which allows multi-media content to be incorporated into a package that can be viewed on a range of devices. The problem with using iAuthor is existing copyright protection of our material by our publisher. Accordingly, we are taking a two pronged approach. First, we are reformatting (and revising) our text so it can be published in an easy to view pdf format by our current publisher. Second, we are exploring other “off-the-shelf” publishing programs that should allow us to incorporate the multi-media content we have produced over the years.

A textbook and CDs produced with previous NSF support.