• Journal of the Korean Ceramic Society
• /
• v.44 no.4 s.299
• /
• pp.194-197
• /
• 2007

Polyacrylonitrile (PAN)/$Fe_2O_3$ nanocomposite membranes with a thickness of 0.02 mm were electrospun by adding 0 to 5 wt% of $Fe_2O_3$ into PAN. The surface tension, density, kinematic viscosity and dynamic viscosity of the PAN solution were determined to be $33.8{\pm}1mN/m$, 0.9794 g/ml, $1548.6mm^2/sec$ and 1516.7 cP, respectively. The average diameters of PAN fibers containing 0, 1 2, 3, and 4 wt% $Fe_2O_3$ particles were 300, 260, 210, 130, and 90 nm, respectively. Fourier-transform infrared spectroscopy results showed that the addition of $Fe_2O_3$ nanoparticles to the PAN mat reduced the absorption peak intensity at $2242cm^{-1}$ ($C{\equiv}N$ bond) while it caused a sharp increase in the peak intensity at $2356cm^{-1}$(C=O bond). Thus, it appears that an appropriate amount of $Fe_2O_3$ nanoparticles in the PAN backbone leads to an improvement of the performance of the $CO_2$ gas sensor, most likely due to the change of functional groups in the membrane.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.11 no.2
• /
• pp.120-129
• /
• 2023

Marine structures are subject to damage not only from sea salt but also from the adhesion of marine microorganisms and suspended particles, which cause additional damages. In order to prevent this, periodic coating is employed in the case of vessels to maintain the necessary performance. However, it is true that periodic coating is difficult for concrete or steel support structures, and there is a risk of marine environmental pollution. In this study, authors developed an anti-fouling coating agent using eco-friendly materials that possess hydrophilic cellulose nanofibers and AKD(alkyl ketene dimer). To achieve a homogeneous mixture, the content of cellulose nanofibers was fixed at 1 %, and AKD, distilled water, and waste glass were mixed using a digital mixer and homogenizer. The contact angle of the prepared coated surface was observed to be over 130°, indicating sufficient performance even in a water droplet flow test with a 15° slope, suggesting self-cleaning capability. Furthermore, through the analysis of viscosity characteristics at different temperatures, it was confirmed that the application is feasible at room temperature. Microstructure analysis also verified that the coating agent is uniformly applied to the concrete surface.