Enhancing the hydrophobicity of PLA filaments for 3D printing parts

Abstract

The demand for hydrophobic materials is at an all-time high in the present day and age, mostly post Covid-19, due to their water-repelling, antibacterial, de-icing, self-cleaning, and corrosion-resistant properties to name a few. However, the manufacturing processes of these hydrophobic materials are generally costly and time-consuming. As a result, this thesis focuses on creating hydrophobic surfaces swiftly and cheaply. In this research, PLA was mixed with various concentrations of Polytetrafluoroethylene (PTFE) and Hexadecyltrimethoxysilane (HDTMS) with the aid of solvents, Dimethylformamide (DMF), Acetone, and Chloroform to create hydrophobic materials through the electrospinning and solvent casting processes. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and Thermogravimetric analysis (TGA) techniques were then utilized to assess the structures, compositions, and thermal decompositions of the samples. Additionally, water contact angle testing was conducted to confirm improved hydrophobicity in the samples created. According to the results obtained, it was discovered that the best results were achieved at a 10wt.% (2g) of PLA, 0.2ml of Hexadecyltrimethoxysilane, and 1ml of PTFE, producing an average water contact angle of 131.6° with the highest WCA obtained being 132.7°. From these results, it was concluded that adding PTFE and Hexadecyltrimethoxysilane to PLA drastically increased its hydrophobicity.