Abstract: Castor oil (CO) and epoxidized soybean oil (ESBO) were used as plantoilbased polyols, based on which four kinds of wrapping polyurethane adhesives were prepared by using isophorone diisocyanate (IPDI), polyethylene glycol (PEG)400 or CO without solvent. TGA, DSC, tensile mechanical properties test, PE/OPP composite membrane peel strength test and shear strength test were carried out for the polyurethane adhesives film. It showed that the polyurethane adhesives prepared by PEG400 and plantoilbased polyols get the peel strength about 200 N/m with the best shear strength 4.9 N/mm^2; polyurethane adhesives prepared by all plant oil get the better thermal decomposition and water resistance properties.

Key words: plant oil, polyols, modification, polyurethane adhesive