Natural Polymer With Adhesive Properties Produced by Bacteria
Numerous studies have examined adhesives made by barnacles and mussels. Although the adhesive materials have amazing properties, large-scale production has been problematic and expensive.
The EPS raw material is called C-902 Polymer. It is a high-molecular-weight polysaccharide made from a renewable resource. It is excreted from the bacterium, allowing it to be inexpensively separated from the biomass. Unlike highly branched polysaccharides such as xanthan gum, C-902 does not expand in water. The water-based polymer is non-cytotoxic and is biodegradable.
The “green” adhesive has good tensile strength and shear strength on aluminum, depending on the surface finish. (See table.) Bond shear strength is greater than the substrate for medium-density fiberboard, particleboard and fir. The material is very resistant to organic solvents such as d-limonene and jet fuel. The cured adhesive loses strength after a few hours under water but maintains full strength in an environmental chamber during an 85-percent humidity, one-week temperature-cycling program between 30 and 60 degrees C. After curing, the adhesive bond can be broken, moistened and rejoined.