3 research outputs found
Amidine-Functionalized Poly(2-vinyl-4,4-dimethylazlactone) for Selective and Efficient CO<sub>2</sub> Fixing
Development of novel polymeric materials
capable of efficient CO<sub>2</sub> capture and separation under ambient
conditions is crucial
for cost-effective and practical industrial applications. Here we
report the facile synthesis of a new CO<sub>2</sub>-responsive polymer
through postpolymerization modification of poly(2-vinyl-4,4-dimethylazlactone)
(PVDMA). The reactive pendant azlactone groups of PVDMA are easily
modified with 4-(<i>N</i>-methyltetrahydropyrimidine)benzyl
alcohol (PBA) without any byproduct formation. FTIR and TGA experiments
show the new PBA-functionalized polymer powder can reversibly capture
CO<sub>2</sub> at room temperature and under atmospheric pressure.
CO<sub>2</sub> capture was selective, showing a high fixing efficiency
even with a mixed gas system (20% CO<sub>2</sub>, 80% N<sub>2</sub>) similar to flue gas. CO<sub>2</sub> release occurred at room temperature,
and release profiles were investigated as a function of temperature.
Density functional theory (DFT) calculations coupled with modeling
and simulation reveal the presence of two CO<sub>2</sub> binding sites
in the PBA-functionalized polymer resulting in a two-step CO<sub>2</sub> release at room temperature. The ease of material preparation, high
fixing efficiency, and robust release characteristics suggest that
postpolymerization modification may be a useful route to designing
new materials for CO<sub>2</sub> capture