Role of Chemical Functionality in the Adhesion of Aluminum and Isotactic Polypropylene

• DOI: 10.1021/acsami.0c22988
• Publication Date: 2021-02-25T15:32:53Z
• Authors: Yida Liu; Yuri Shigemoto; Takeshi Hanada; Takayuki Miyamae; Kazunori Kawasaki; Shin Horiuchi
• Keywords: Tacticity; Polypropylene

In the direct melt bonding of isotactic polypropylene (iPP) to aluminum (Al), blending a small amount maleic anhydride-grafted PP (PPgMA) with iPP was found induce dramatic improvement strength adhesion. The effect PPgMA was, however, limited, maximizing at ∼20 wt % PPgMA. Incorporation larger amounts reduced We studied mechanism adhesion between Al and by incorporating chemical functionality polymer side. fracture surfaces produced peeling off interfaces were investigated replicating surface topographic features on platinum thin film analyzing them scanning transmission electron microscopy (STEM) as well reconstructing three-dimensional (3D) structures STEM tomography. replica-STEM technique enabled us visualize crystalline lamellar their deformation upon failure in 3D. that polymer/metal similar those associated entanglement-based polymer/polymer via chain pullout. A fractography study suggested formation low-molecular-weight layer low crystallinity interfacial region responsible for depended toughness "soft layer" did not depend Al. reaction MA yielded grafted carboxylic acid (−COOH) group, which may have been excluded from lamellae. concluded primary reason adhesion, but it necessary segregation soft layer.