SYNTHESIS AND CHARACTERIZATION OF PLA-NANOCOMPOSITES USING VARIOUS TYPES OF NANOCLAYS

• Main Author: Paramitha, Tika
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/32952
• Institution: Institut Teknologi Bandung

The use of plastic increases steadily along with the large number of human populations. Currently most of the plastics are produced from petroleum which are difficult to degrade. Poly(lactic) acid (PLA) is a raw material of plastic from renewable resources which is promising due to its environmentally friendly, ease of processing, and biocompatibility. However, there are PLA properties that need to be improved, such as: mechanical properties, slow biodegradation rates, and poor barrier properties. Combination of PLA with fillers can improve PLA properties. The main objective of this research is to produce PLA-nanocomposites using various types of nanoclays that have better properties than neat PLA and PLA-biocomposites as comparison. In this study, the production of nanocomposite film and biocomposite film by mixing PLA and nanoclay and PLA and cellulose using extrusion, respectively. Several types of nanoclay will be applied to PLA-nanoclay synthesis, such as: regenerated organobentonite, commercial organobentonite, and Cloisite 30B. Regenerated organobentonite is Spent Bleaching Earth (SBE) that has been regenerated and modified using organic compound. Meanwhile, commercial organobentonite is commercial bentonite modified using organic compound. Furthermore, biocomposite film is produced from PLA and cellulose of Oil Palm Empty Fruit Bunch. In the extrusion method, PLA and nanoclay or PLA and cellulose are heated above the melting point of PLA using the extruder. The product of extruder in the form of pellets are pressed using compression molding machine to form nanocomposite film and biocomposite film. The XRD characterization show that nanocomposite structures are partial exfoliation. The best mechanical properties of the nanocomposites, such as elongation at break, tensile strength, and modulus young at low nanoclay compositions (0.5-1% nanoclay weight). This is supported by SEM analysis showing smooth morphology of surface of the nanocomposite at low clay compositions. Increasing the composition of nanoclay up to 5% weight results in the interaction of filler-filler and the formation of agglomerates that decrease the mechanical properties of nanocomposite. The water absorption properties of nanocomposites with the addition of nanoclay 0.5-1% weight slower than neat PLA, so the biodegradation rate becomes slow at 30 days of biodegradation time. iv However, the water absorption and biodegradability rate increase with the increasing composition of nanoclay. The mechanical characterization of biocomposite film, such as elongation at break, tensile strength and modulus young decrase compared to neat PLA. This is because the adhesion between cellulose and matrix is weak. The water absorption properties of biocomposites are higher compared to neat PLA. Furthermore, the water absorption properties are high resulted in biodegradation rate faster than neat PLA.