• SRIPARNA CHATTERJEE

Articles written in Bulletin of Materials Science

• Development of polymer-based superhydrophobic coating on cloth

Facile, one-step fabrication of durable, superhydrophobic (water contact angle $\sim$154$^{\circ}$) fluorine-free polymer coating on cotton cloth is presented. The microstructure of the coating is evaluated with electron microscopy and X-ray diffraction study. The detailed analysis reflects that the superhydrophobicity is rendered by intrinsic hydrophobic nature of thenon-polar polymer, isotactic polypropylene. The chemical and mechanical stability of the coating on cloth is evaluated and it shows that the coating is extremely resilient in nature without almost negligible sacrifice in water contact angle. Because of simplicity of fabrication technique and quality of coating, this study is expected to be worthy enough for commodity as well as high technology applications.

• Corrosion resistance performance of electrophoretically deposited graphite–chitosan composite coating on copper

Development of graphite and graphite–chitosan composite coating on copper (Cu) substrate is carried out using electrophoretic deposition. Further, post-treatment is done using ethanolic solution of 20 wt% methyl hydrogenpolysiloxane (KF-99) to improve coating adhesion with the copper substrate. The corrosion resistance of the post-treated coating is examined in 3.5 wt% NaCl solution. Field-emission scanning electron microscope reveals that the addition of chitosan leads to densification of the coatings. A reduction in the $I_D$/$I_G$ ratio of the graphite–chitosan composite coating compared to graphite coating implies a decrease in the defect in the coating. An increase in corrosion potential of 0.29 V isnoticed for graphite–chitosan composite coating compared to pure copper, i.e., –0.02 V. The corrosion rate is reduced to 34% for graphite coating (0.070 mmpy) and 51% for graphite–chitosan composite coating (0.050 mmpy) as compared topure copper (0.102 mmpy) substrate. The pure copper substrate shows the lowest polarization resistance ($R_p$ ${\sim}$ 40.23 ${\Omega}$.cm$^2$) that is drastically enhanced in the case of graphite–chitosan composite coating ($R_p$ ${\sim}$ 4327 ${\Omega}$.cm$^2$). Enhancementin the corrosion resistance of the graphite–chitosan composite-coated sample is attributed to the formation of a protective barrier layer of SiO$_2$ and chitosan, which acts as an obstacle to ion transportation between the copper substrate and NaCl solution.

• # Bulletin of Materials Science

Volume 46, 2023
All articles
Continuous Article Publishing mode

• # Dr Shanti Swarup Bhatnagar for Science and Technology

Posted on October 12, 2020

Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020