Professor of the Department of Mechanical Engineering, Faculty of Engineering Universitas Indonesia, Prof. Dr. Ir. Tresna Priyana Soemardi, S.E., M.Sc., IPU ASEAN-Eng became the first in Indonesia to develop an environmentally friendly Pre-Impregnated (Prepreg) material called Ramie Fiber Reinforced (RFR) – PolyLatctic Acid (PLA). This innovation is the collaboration result with the Composite Laboratory of the Université Paris Nanterre, Ville DAvray, Paris, France with the Mechanical Design, Biomechanics and Composite Sub-Lab Laboratory, Department of Mechanical Engineering, Faculty of Engineering, Universitas Indonesia.
Prepreg is a semi-finished composite material commonly used in material manufacturing, consisting of a natural polymer matrix (PLA) and natural reinforcing fibers from hemp trees. From 2020, this research is presented as a solution to the needs of conventional Prepreg market commodities which generally use synthetic fibers such as carbon, glass, and Kevlar. “Compared to Prepreg which uses synthetic fiber, RFR-PLA Prepreg has more affordable price, is environmentally friendly, light, and has lower emissions,” said Prof. Tresna. The advantages of Prepreg are the result of innovation. Tresna lies in using local hemp fiber as its primary raw material.
Since the end of 2023, Prof. Tresna and his doctoral program students, Ardy Lololau, Herry Purnomo and Mustasyar have collaborated with hemp cultivators in West Java under the supervision of the Textile Center. This collaboration aims to produce hemp fiber into yarn and fabric, empower local farmers, and increase the Domestic Content Level value.
This local hemp fiber was then taken to France for further research at the Composite Laboratory with Prof. Olivier Polit, Vice-Chancellor of Université Paris Nanterre and Head of the Electronics, Mechanics, and Magnetics Laboratory. Prof. Tresna said, “This original discovery has gone through a long series of research processes since 2000. We continue to conduct trials from various aspects, from composition, equipment, process, and temperature to achieve the best prototype version. The Prepreg prototype being developed has now reached the Delta version (𝛿).”
Professor in Mechanical Design & Construction and Applied Mechanics for Composite Materials, also said that at the test stage with multiaxial loads, this prototype showed satisfactory results with a strength of 60-80 megapascals (MPa) at 0° and 20-40 MPa at 90°. Furthermore, there is no significant difference between imported and local hemp fiber. This trial is part of an effort to create Prepreg RFR-PLA with an optimal manufacturing process, namely ease of production process on an industrial scale.
Currently, the RFR-PLA copyright patent is being submitted through the UI Innovation and Science Techno Park (DISTP) Directorate. After this material successfully meets test standards, it will be applied to automotive bodies and interiors. It is currently starting to be applied to structural models and aircraft bodies and has the potential to be used for fishing boats. RFR-PLA will mainly be used in automotive bodies and structures and rotating parts, which are the heaviest parts of automotive components because the use of composites can reduce vehicle weight by 20-30 percent. This material can also be applied to household appliances.
This innovation was strengthened through the Séjour Scientifique de Haut Niveau (SSHN), a high-level scientific research collaboration scholarship program led by Prof. Tresna. From November 2023 to January 2024, Prof. Tresna came to Université Paris Nanterre to conduct research for the SSHN program. Prof. Tresna revealed that this program really helped his research in producing the need for advanced polymerization manufacturing processes.
Prof. Tresna said that in Indonesia, research on this material is still relatively rare, making it difficult to meet research needs in terms of both equipment and human resources. The existence of this collaborative scholarship program is very helpful in elaborating on the performance of Prepreg which is being developed, especially for multiaxial static and fatigue loading experiments.
Dean of Faculty of Engineering UI, Prof. Dr. Heri Hermansyah, ST., M.Eng., IPU fully appreciates the creation of the RFR-PLA innovation. He said, “The collaboration between UI and Université Paris Nanterre in the development of Prepreg allows Prof. Tresna to access state-of-the-art research facilities and collaborate with experts in the field. This also shows UI’s commitment to establishing international collaboration with leading universities in the world and opens up opportunities for technology transfer and further research development.
The results of this collaborative research will be published with the title “Experimental Study on Mechanical Behavior and Damages of Ramie Fiber-Reinforced PolyLatctic-Acid Natural Prepreg Composite Under Multiaxial Loading Using Modified Arcan Fixture.” In the future, Prof. Tresna will also publish a book entitled Development of Natural Composites and Their Use in Human Life and Advanced Industry, collaborating with Prof. Olivier.
