Polyurethane/clay nanocomposites from palm oil for surface-coating applications

Abstract

Synthesis of palm oil-based polyurethane (PU) and the formation of nanocomposite from a mixture of PU with clay filler has been performed. Polyol which is the basic material of PU is formed by epoxidation and hydroxylation process and then mixed with isocyanate. Clay used as filler in this study was obtained from the local area of North Aceh, which is a type of swelling of clay that has been modified with cetyltrimethyl ammonium bromide surfactant. Nanocomposites are formed from PU with clay fill variations of 3%, 5%, and 8% by weight of the total mixture of 40 g. The resulting material is tested in character by some type of characterization. Based on the test results with Fourier transform infrared spectroscopy, the hydroxyl polyol group was obtained in groups of 3390.870 (O–H) and –NH as the PU microdomain structure was obtained at a wavelength of 2987 cm−1. Morphological test results using scanning electron microscopy revealed that the addition of modified clay increases the adhesion in the paint and PU coatings and also increases the gloss from the surface and homogeneous material. The thermal endurance test with thermogravimetric analysis reported that the addition of clay fillers in PU showed enhanced effects for better thermal stability in nanocomposite materials when compared with neat polymers. Samples of PU/clay nanocomposites with the addition of 8 wt% clay filler were the most optimum composites among other variations with the thermal degradation temperature value of 296°C. This research generates prospects for applying various industrial surface coatings that are resistant to corrosion and heat, have good mechanical properties, and are more environmentally friendly.