Manufacturing and Characteristic Evaluation of High‐Adhesion Acrylic Adhesive Film for Electromagnetic Wave Shielding

ABSTRACT In this study, an acrylic‐based adhesive film with excellent electromagnetic shielding performance and adhesive strength was fabricated, and its properties were evaluated. The film was synthesized by copolymerizing butyl acrylate (BA), 2‐ethylhexyl acrylate (2‐EHA), 2‐hydroxyethyl acrylate (2‐HEA), and acrylic acid (AA), with the ratio of AA to 2‐HEA adjusted to optimize adhesion and material properties. AA increased the polarity of the polymer, enhancing adhesion through hydrogen bonding, while 2‐HEA contributed to both adhesion and crosslinking. As the AA content increased, the adhesive strength improved, ranging from 504.73 N/m to a maximum of 812.6 N/m. After adding 20 wt% Ni powder, the adhesive strength ranged from 331.89 N/m to a maximum of 700.79 N/m. The rate of peel strength reduction caused by Ni addition decreased as the AA content increased. The vertical and horizontal resistances of the resulting adhesive film were measured to be 0.43 mΩ and 0.11 Ω, respectively, indicating low electrical resistance. The electromagnetic shielding performance was measured according to ASTM D4935 using a vector network analyzer, over a frequency range of 9 kHz–8.5 GHz, and exhibited an average shielding effectiveness of approximately 63.7 dB. These findings suggest that the developed adhesive film is well suited for use in flexible electronics and other applications requiring both strong adhesion and electromagnetic shielding.