Some detail explanation on the influence of anneal on the properties including transmittance, refractive index, and volume fraction porosity of the SiO2 thin films were also given.

According to the simulated temperature fields and solid fraction, the hot spot and shrinkage porosity are not found in the bolster casting, so the new casting process is feasible.

With the increasing of mass fraction of PEG, membrane porosity and pure water flux become larger, and the maximum tensile strength and elongation at break of the membrane criterion decrease gradually.