Preparation and thermal characterization of the glass transition temperatures of sulfonated polystyrene-metal ionomers

✍ Scribed by Sen Yang; Kang Sun; William M. Risen Jr.

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 760 KB
• Volume: 28
• Category: Article
• ISSN: 0887-6266
• DOI: 10.1002/polb.1990.090281004

✦ Synopsis

Abstract

The glass transition temperatures and heat capacity changes in the transition region are reported for six sulfonated linear polystyrenes in the hydrogen form, H‐SPS, in the 3.4–20.1 mol % sulfonation range and 76 metal SPS ionomers in the 3.4–12.8 mol % range. The metals are those which interact predominantly ionically and include +1, +2, and +3 ions of the alkali metal, alkaline earth, and rare earth (lanthanide) series. The results show the effect of H~2~O or coordinating ligands on glass transition temperatures (T~g~) and the importance of eliminating it to obtaining reproducible values for T~g~ and Δ__C__~p~. The T~g~ values of dry M‐SPS ionomers depend only on the sulfonation level despite wide variation in metal ion charge and size. The variation of Δ__C__~p~ with sulfonation level is interpreted as showing that at high levels a few unsulfonated styrene units adjacent to sulfonated ones are constrained, presumably by clustering, from participation in the polystyrene‐like cooperative rearrangements in the transition region.