Struct Chem
0
.5 wt% loading of catalyst (Fig. 7). Although the same
The methodology of pre-formed porous polymers using
a porous silica template can offer a convenient synthetic
platform for creation of solid catalysts with a variety of
micro- and meso-porous structures that will be used in
broader catalysis applications.
weight percent of catalysts was employed, A15 has a much
more acidic groups per gram because of its higher loading
capacity (4.8 mmol/g). This value is almost five times higher
than that of SAC1 (1.02 mmol/g). Nafion has a similar molar
loading capacity of 0.90 mmol/g but it does not have a porous
structure. Due to the high acid loading capacity, A15 showed
good conversion throughout the reaction, achieving complete
conversion in 4 h. With the same 0.5 wt% of catalyst loading,
the activity of SAC1 was comparable to that of A15 under the
entire reaction period. This is possibly due to the mesoporous
structure of SAC1 which allows easy access of reactants into
the pores of the catalyst and facilitates mass diffusion of reac-
tants and product. Additionally, the hydrophobic surface of
pores made of polystyrene with a high degree of cross-
linking density would be helpful to achieve good catalytic
performance by repelling water that is formed as a byproduct,
otherwise it may push the reaction back to an equilibrium [22].
In spite of having a similar acidity strength of SAC1, NR50
showed much lower conversion because of its non-porous
structure and low surface area [23].
Acknowledgments The authors appreciate the generous support of the
Rensselaer Polytechnic Institute (Bae startup) for this work.
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