Thx Kpnuts,
Well, I'll tell you what I did, even though I am not sure whether it will be a success yet or not.
So, I bought pre-vulcainised "esprit composite" Latex with black die (which looks alot like smoke black)
Then, I h=just dipped my moulds into the latex:


in between layers or dips, I wait for it to cure about 1/2 an hour. To go quicker, I stuck the moulds into my oven at 70° C. I have tried to take one of the socks off a mould after 4 layers and it came off nicely. The only thing is that the exterior was about 0.3mm thick and a bit sticky so that it just clumped.
I then learned that it takes 24 hrs for it to dry up completely.
So, in the end, I ended up applying 8 layers and I cut some of the excess off to control thickness which is about 0.7mm:


The properties of Latex are as followed
-shore hardnessv80
-Elasticity 700%
These should make nice blastbags
We see what happens next Saturday as it takes 24hrs to cure completely. To take it off the molds, the exterior has to be coated in washing up liquit to prevent the sock sticking to itself.
Cheers
Serge