Polycaprolactone and acylated soy protein isolate to tune the features of brown seaweed biocomposites

Abstract

Abstract Invasive brown seaweed Rugulopteryx okamurae (RO) can be used as basis of biocomposites with different polymers, such as polycaprolactone (PCL) or acylated soy protein isolated (SPIa). The addition of PCL can strengthen the biocomposite and the elastic modulus (E') goes from ~ 110 MPa to ~ 250 MPa. Nevertheless, when SPIa is added, a softening takes place, leading to E’ values around 40 MPa. The addition of PCL or SPIa induces a greater deformability in the systems, with a maximum deformation (~ 2.25 or ~ 23%) for a 70/30 or 25/75 ratio, respectively. The presence of PCL reduces the absorption of water, while SPIa produces a substantial increase to the point of obtaining superabsorbent materials at a 25/75 ratio (~ 2450 wt.%). In conclusion, the adequacy of the seaweed materials for different applications can be modulated through the addition of an adequate filler.