The suitability of the different extractions was evaluated in
terms of yield, film-forming ability and preliminary film water
response. Four Laminaria (L) and Ascophyllum (A) extracts with the
highest yields and filmogenic capacity were selected for further
film characterization, two prepared with Na2CO3 (Lc, Ac) and the
other two with NaOH (Lh, Ah).