Production of an Agro - based thermoplastic composite using Hibiscus Cannabinus L as reinforcing fillers by microwave irradiation

• Main Authors: Davadilla, Reginald D., Salonga, Ivan Martin M., Tan, Eleanor
• Format: text
• Language: English
• Published: Animo Repository 2006
• Subjects: Thermoplastic composites; Kenaf; Polyethylene; Chemical Engineering
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/9307
• Institution: De La Salle University

As populations continue to rise and as daily activities become more dependent on plastic products, the global demand for plastics has contributed additional problem to solid waste management. The discovery of starch-based and agro-based plastics opened more possibilities in minimizing, if not solving, the waste problems. This study aimed to produce an agro-based thermoplastic composite using Low Density Polyethylene (LDPE) with Hibiscus Cannabinus L. (kenaf) as reinforcing filler using microwave irradiation. The raw materials used were recycled Low Density Polyethylene (RLDPE), virgin Low Density Polyethylene (VLDPE), and kenaf fibers. Experiments were conducted using three methods: preliminary test run, injection molding, and microwave irradiation. The Preliminary Test Run used oven toaster as the primary equipment Injection Molding Method used AMATROL-T9013P and Microwave Irradiation Method used a fabricated microwave oven and a granite reactor. The preliminary test run was used to produce both LDPE films with 0%, 2%, and 4% (w/w) kenaf. The average residence time used was 5 minutes. On the other hand, pure films of VLDPE were processed using injection molding method. Residence time for VLDPE was not monitored. Lastly, RLDPE films with 0%, 2%, 4%, and 6% (w/w) kenaf and VLDPE films with 0% and 4% (w/w) kenaf were processed using microwave irradiation method. Residence time used was 15 minutes. Processing temperatures used for both Preliminary Test Run and Microwave Irradiation Method were 120°C. For the injection molding method, the processing temperature was 200°C. Results show that increasing the amount of filler decreased the tensile properties of all composites produced except for 2% (w/w) kenaf. It was found out that the 2% (w/w) kenaf composite exhibited the highest tensile strength (8.17 N/mm²) and elongation at break values (26.4%) among all of the RLDPE films produced by Microwave Irradiation Method. This was followed by the pure plastic film with a tensile strength of 8.05 N/mm² and 20% elongation at break.