The adhesive properties of the blends of isotactic polypropylene with ethyl
ene-acrylic acid copolymers were investigated. It was found that the surfac
e free energy, polar component of surface free energy, polar fraction and m
echanical work of adhesion increased with concentration of EAA copolymers i
n the iPP blends to a degree exceeding additive function. The proportionali
ty of mechanical work of adhesion of the polymer blends to polar fraction t
hat reflects the strength of adhesive joint was also revealed. This observa
tion permits us to claim that the increase in polarity or hydrophilicity of
iPP due to modification in bulk by the use of polar EAA copolymer raises t
he strength of adhesive joints between iPP and more polar polymers. The rel
ationship between mechanical properties of the studied polymer blends and t
heir composition showed the functional additivity of the mechanical paramet
ers. (C) 2001 Kluwer Academic Publishers.