Plasticizing Effects of Imidazolium Salts in PMMA: High-Temperature Stable Flexible Engineering Materials

Abstract

The unique, environmentally-sound applications of ionic liquids (ILs) are well-known, and include use as green solvents for a variety of chemical processes. Because ILs are stable liquids over a wide temperature range, they offer technological advantages over some chemicals used in their liquid phase, such as plasticizers, where polymer flexibility can be enhanced. Common problems with plasticizers include evaporation and leakage from the surface, instability at high temperatures, lack of lubrication at low temperatures, migration within the polymer, and toxicity. We have addressed couple of these issues using poly(methyl methacrylate), PMMA. Systems studied include bulk PMMA, and PMMA plasticized with butyl methylimidazolium hexafluorophosphate [bmim + ][PF 6 -], hexyl methyl imidazolium hexafluorophosphate [hmim + ][PF 6 -], and a traditional plasticizer, dioctyl phthalate (DOP). Experiments indicate that high temperature stability is improved significantly by replacing DOP with an IL. The effect of IL on glass transition temperature and elastic modulus were also determined. Ionic liquids as plasticizers may revolutionize the usage of flexible polymers at high temperatures, without brittleness or loss of mechanical strength.468

Ionic liquids as lubricants of polystyrene and polyamide 6-steel contacts. Preparation and properties of new polymer-ionic liquid dispersions

“…In contrast with the plasticizing effect found for previously described [15,16] thermoplastic-imidazolium ionic liquid blends, DSC studies (table 2) show that the glass transition temperatures of the PS+IL1 blends are similar or higher than that of neat PS. The cryofracture surfaces of the neat polymer (figure 6(a)) and the PS+1%IL1 blend (figure 6(b)) show similar fracture modes.…”

“…Table 3 shows glass transition temperatures and degradation temperatures for neat PA 6 compared with that of PA6+3%IL4 and with the neat polymer after been immersed in IL4 for 100 h. While immersion in IL4 does not affect the glass transition temperature of PA 6, the addition of IL4 has a plasticizing effect [15,16] on PA 6 as shown by the 9°C decrease in T g with respect to the neat polymer. This is in contrast to the influence of IL1 on the thermal properties of PS (table 2).…”

“…A great attention has also been focused on polymer-ILs interactions [15][16][17][18][19][20][21][22][23]. The use of ILs as solvents in polymerization processes has promoted research on their influence on the final products properties.…”

“…The use of ILs as solvents in polymerization processes has promoted research on their influence on the final products properties. It has being found that ILs can act as convenient non-volatile plastizicers when added to thermoplastics such as polymethylmethacrylate (PMMA) or polyvinylchloride (PVC) [15,16] while having a hardening effect on epoxy thermosets [17,24].…”

Ionic Liquids Interactions with Materials Surfaces Applications in Tribology and Nanotechnology

“…When internal lubricants are used, it is necessary to control the rate at which the lubricant is segregated out from the bulk onto the surface [47][48][49][50]. When internal lubricants are used, it is necessary to control the rate at which the lubricant is segregated out from the bulk onto the surface [47][48][49][50].…”