FABRICATION OF HYDROPHOBIC SURFACE ON POLYVYNIL CHLORIDE AS HELMET VISOR

• Main Author: Adi Prastowo, Dian
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/36296
• Institution: Institut Teknologi Bandung

Common problem encountered during motorcycling when it rains is vision disturbance as the raindrops stick to the helmet visor and don’t slide down. It happens because PVC as one of the visor’s material is basically hydrophilic which means surface has strong adhesion to the raindrops so the raindrops can’t escape from the surface easily. To overcome this problem, it is necessary to render the visor hydrophobic, so the visor don’t have strong adhesion to the water molecule. Yet it must be transparent so the rider could see clearly beyond the PVC visor. There are two steps to make a hydrophobic layer: by inducing roughness on the surface then lower the surface energy of the visor. In this research, two methods are used to induce surface roughness, first by chemical etching and second by nanosilica depisition; whereas to lower the surface energy, two methods are used: first is stearic acid deposition and second is dodecanethiol deposition, as the two are basically amphiphilic. First, by chemical etching by xylene followed by dodecanethiol deposition, the contact angle produced is 92,17° and the sliding angle is 22,2°. Second, by depositing nanosilica and stearic acid, contact angle produced is 148° with 8° sliding angle. Both method results in high visible light transmittance, with maximum 67% transmittance by the first method and minimum 72% transmittance in the second method.