An A-cat hull is about 7 sq. mtr. in surface area and weights about 14 kg.

The specs you give for the new material ; 1.5 gram / cm3 = 1500 kg / m3 suggest that you can make the A-cat hulls of the your material only 14 / (7.5 * 1500 ) = 1.24 mm thick. That is not going to hold.

FX-one hull weights about 35 kg and has about 8.5 sq.mtr. surface area => max thickness with new material = 2.75 mm

You are not going to make lightweight hulls with this new material.

For example marine ply comes in around 600 kg/m3. You can get 2.5 times the thickness for the same weight by using this time tried material. And thickness counts in boat building.

Sorry

Wouter