“…However, during heating, orthophosphoric acid (H 3 PO 4 ) will progressively condensate to H 4 P 2 O 7 , HPO 3 , and P 2 O 5 to finally evolve from the materials at higher temperatures. In all the previously mentioned studies, simple or complex thermal treatments were used [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ] but many papers only referred to the final curing temperature [ 1 , 4 , 11 , 12 , 14 ] with no real consideration for the effect of the heating rate used to reach this temperature. When the heating rate is mentioned [ 2 , 3 , 7 , 8 , 9 , 13 ], this parameter does not seem to be optimised, although it can be considered a key parameter.…”