The choice of raw materials also limits the range
of combinations of variables possible. For example,
the results of this study would indicate that a formulation
1.2Na2O·3.5SiO2·0.8Al2O3·12H2O would be
the strongest inorganic polymer, however with the
raw materials used here this would not be possible,
and 1.2Na2O·3.5SiO2·0.8Al2O3 would require 24H2O
which would be unlikely to set. Thus, as many studies
have shown in the past, raw materials selection is the
key to high-performance inorganic polymers