Self‐healing nanocomposite film of polyvinyl alcohol—polyacrylic acid incorporated with iodine.

Self‐healing polyvinyl alcohol‐polyacrylic acid (PVA‐PAA) composite films incorporated with molecular iodine (I2) are presented for optoelectronic applications. The incorporation mechanism between the PVA‐PAA donor and I2 acceptor is investigated by studying the chemical, crystal, and morphological properties of the composite films. Incorporating PVA‐PAA composite films with I2 decreases the crystallinity degree of the composite films, which increases the electrical conductivity by enabling the segmental motion in the polymer matrix. PVA‐PAA/I2 composite films are stable at temperatures lower than 200°C, where the majority of optical, optoelectronic, and electrical applications can be realized. Additionally, introducing I2 into the PVA‐PAA matrix increases the melting temperature of the composite films. Moreover, the optical and electrical properties of the PVA‐PAA/I2 composite films are investigated. The bandgap energy of PVA‐PAA film is 3.88 eV, decreasing continuously to 3.38 eV as I2 concentration increases to 16 wt.%. On the other hand, The average conductivity of the PVA‐PAA film is 7.46×10−6S×cm−1. Increasing I2 concentration in the PVA‐PAA matrix increases the electrical conductivity continuously up to 1.33×10−4S×cm−1. The physical properties of the PVA‐PAA/I2 composite films exhibit self‐healing properties after thermal treatment and UV irradiation that occur during the operation cycling in optical, optoelectronic, and electrical applications. [ABSTRACT FROM AUTHOR]