“…About 98.5% (2,105 entries) of the proton conductivity and 42.6% (801 entries) of the water uptake data set involve the ionic −SO 3 – sulfonate group. From the data learning standpoint, data sets of correlated properties can be fused and learned simultaneously in a multitask (MT) ML model so that possible hidden correlations among them can be accessed. , Likewise, a data set of 2624 data points for the permeabilities of six gases, including H 2 , O 2 , He, CO 2 , N 2 , and CH 4 , were taken from previous works, , augmented, and learned in another MT model. Four other data sets of polymer band gap E g , thermal decomposition temperature T d , glass transition temperature T g , and Young’s modulus E were also utilized from past works. ,, We note that, among these data sets, only those for σ and λ contain the temperature T , the relative humidity RH, and information on if the water is in the liquid form or not, when the measurements were made.…”