u00b0 c was increased to reach 2 hrs 10 mins in the same way the time for cooling the mold at room temperature was extended to reach 2 hrs 30 mins whereas the first sample bd1 1 had lumps after de molding the appearance of the bd1 2 sample was satisfactory the mass of the bd1 1 and bd1 2 samples after de molding was 99 8 and 113 8 g respectively their final mass were 100 7 and 113 g respectively materials bd6 1 and bd6 2 were realized respectively using the same methods the mass of these samples once de molded was 112 1 and 113 2 g respectively and their appearance was satisfactory as for the first material the objective was to reach a density of the order of 280 u00b1 10 kg m3 for a mass of the order of 100 g the operating procedure for realizing the two samples bd4 1 and bd4 2 of the second material is described in the table below the appearance of the two samples obtained is correct the mass of the samples bd4 1 and bd4 2 after de molding is 92 2 and 92 5 g respectively the final mass of the samples was 94 7 and 95 g respectively the mass of acetate in the finished samples is missing because the acetate evaporated during polymerization in summary the start proportions of the chosen materials are in the table below in which the boxes marked with an u201c x u201d indicate that the ingredient in question is absent consequently low density materials are obtained which comprise a large proportion of cork as regards the density conductivity and diffusivity characteristics in comparison with those of.