Electronic Theses and Dissertation

Penelitian ini bertujuan untuk menganalisis pengaruh variasi jenis resin terhadap kekuatan tarik dan karakteristik getaran bebas komposit berpenguat serat limbah mesokarp kelapa sawit (Elaeis guineensis). Spesimen komposit dibuat menggunakan metode hand lay-up dengan perbandingan 80% resin dan 20% serat, serta diberi perlakuan alkali menggunakan larutan NaOH 5% selama 1 jam. Variasi resin yang digunakan meliputi resin poliester, epoksi, dan bisphenol. Pengujian tarik dilakukan berdasarkan standar ASTM D3039, sedangkan pengujian getaran bebas mengacu pada standar ASTM E756-05 untuk memperoleh nilai frekuensi pribadi dan rasio redaman. Hasil pengujian menunjukkan bahwa nilai kekuatan tarik tertinggi diperoleh pada komposit resin epoksi sebesar 46,34 MPa, sedangkan nilai terendah terdapat pada komposit resin bisphenol serat sawit sebesar 14,42 MPa. Pada komposit berpenguat serat, kekuatan tarik tertinggi dicapai oleh komposit epoksi serat sawit sebesar 20,78 MPa. Hasil pengujian getaran bebas menunjukkan bahwa frekuensi pribadi tertinggi terdapat pada resin epoksi sebesar 133,14 Hz, sedangkan frekuensi terendah terdapat pada resin poliester. Selain itu, rasio redaman tertinggi diperoleh pada resin poliester sebesar 0,042, sedangkan rasio redaman terendah terdapat pada resin epoksi. Dengan demikian, jenis resin berpengaruh signifikan terhadap sifat mekanik dan respons getaran bebas komposit serat mesokarp kelapa sawit.

Kata kunci: Komposit Serat Alami, Resin Poliester, Resin Epoksi, Resin Bisphenol, Kekuatan Tarik, Getaran Bebas

This study aims to analyze the effect of various resin types on the tensile strength and free vibration characteristics of composites reinforced with oil palm (Elaeis guineensis) mesocarp waste fiber. Composite specimens were made using the hand lay-up method with a ratio of 80% resin and 20% fiber, and were treated with alkali using 5% NaOH solution for 1 hour. The resin variations used included polyester, epoxy, and bisphenol resins. Tensile testing was carried out based on the ASTM D3039 standard, while free vibration testing referred to the ASTM E756-05 standard to obtain the natural frequency and damping ratio values. The test results showed that the highest tensile strength value was obtained in the epoxy resin composite at 46.34 MPa, while the lowest value was found in the palm fiber bisphenol resin composite at 14.42 MPa. In fiber-reinforced composites, the highest tensile strength was achieved by the palm fiber epoxy composite at 20.78 MPa. The results of the free vibration test showed that the highest natural frequency was found in the epoxy resin at 133.14 Hz, while the lowest frequency was found in the polyester resin. In addition, the highest damping ratio was obtained in the polyester resin at 0.042, while the lowest damping ratio was found in the epoxy resin. Thus, the type of resin significantly influences the mechanical properties and free vibration response of the oil palm mesocarp fiber composite. Keywords: Natural Fiber Composites, Polyester Resin, Epoxy Resin, Bisphenol Resin, Tensile Strength, Free Vibration