Finding
A mechanism that the hydrogen bonds between the amide groups of PNIPAAm were interfered by the exfoliated MMT nano-platelets for the MMT/PNIPAAm nanocomposites and the preferred absorption of acrylamide units to the MMT nanoplatelets rather than N-isopropylacrylamide in the MMT/P(NIPAAm-co-AAm) nanocomposites was suggested to interpret these unusual transition behavior.
Paper
Atypical transition temperature dependence of poly(N‐isopropylacrylamide) and poly(N‐isopropylacrylamide‐co‐acrylamide) nanocomposites on the content of exfoliated montmorillonites
Citations: 9
Full textAbstract
Exfoliated montmorillonite (MMT)/poly(N-isopropylacrylamide) (PNIPAAm) and MMT/poly(N-isopropylacrylamide-co-acrylamide) [P(NIPAAm-co-AAm)] nanocomposites were fabricated by soap-free emulsion polymerization. Interestingly, as the content of MMT was increased from 0 to 10 wt %, the glass transition temperature of MMT/PNIPAAm was decreased from 145 to 122 °C, whereas that of the MMT/P(NIPAAm-co-AAm) increased from 95 to 153 °C. Although the lower critical solution temperature (LCST) of 32 °C for the MMT/PNIPAAm nanocomposites in aqueous solutions was slightly increased with the content of MMT, that of the MMT/P(NIPAAm-co-AAm) was decreased from 70 to 65 °C. A mechanism that the hydrogen bonds between the amide groups of PNIPAAm were interfered by the exfoliated MMT nano-platelets for the MMT/PNIPAAm nanocomposites and the preferred absorption of acrylamide units to the MMT nanoplatelets rather than N-isopropylacrylamide in the MMT/P(NIPAAm-co-AAm) nanocomposites was suggested to interpret these unusual transition behavior. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 524–530, 2009
Authors
M. Yen, King-Fu Lin
Journal
Journal of Polymer Science Part B