Characteristics and properties of wood/polyaniline electromagnetic shielding composites synthesized via in situ polymerization

Semiconducting wood/polyaniline (PANI) composites were synthesized via in situ polymerization of aniline monomer, which was impregnated into the wood veneer in advance. Thus, the resulting composites exhibited the characteristics of the conducting PANI and natural wood. The light microscopy and scanning electron microscopy images showed that PANI was uniformly dispersed into the wood substrate. The weight percent gain and volume bulk increase of the composites were 16.13% and 6.21%, respectively. The equilibrium water absorption studies showed that the composites were less hydrophilic, because of the addition of hydrophobic PANI. The electrical conductivity of the wood/PANI composite ranged from 2.57 × 10⁻⁵ to 9.23 × 10⁻³ S cm⁻¹ and was tuned by changing the phosphoric acid concentration. The electromagnetic shielding effectiveness of the wood/PANI composites was mainly in the range 30–60 dB, which may be used for general industry or commercial electronics. Fourier transform infrared spectra revealed that PANI was closely polymerized onto the wood substrate and allowed the accessibility of the amine groups of the aniline to the hydroxyl groups of the wood. Furthermore, the X‐ray diffraction analysis indicated that the crystal lattice of the crystalline cellulose region was not damaged, and the relative crystallinity of wood increased. POLYM. COMPOS., 39:537–543, 2018. © 2016 Society of Plastics Engineers