ABSTRAKPerkembangan penelitian komposit diperkuat serat alam telah menunjukkan hasil yang signifikan. Komposit diperkuat serat daun nanas Subang (SDNS) untuk aplikasi non-struktural memberikan nilai tambah untuk limbah serat daun nanas Subang. Penelitian ini bertujuan untuk mengamati kekuatan lentur, absorpsi dan desorpsi air komposit yang mengacu pada Standar Nasional Indonesia (SNI). Perlakuan alkali pada SDNS dilakukan dengan merendam SDNS dalam larutan NaOH 5%. SDNS setelah perlakuan alkali dan lembaran PP dibuat menggunakan teknik compression molding dengan variasi fraksi berat serat untuk PP adalah 20wt%, 30wt% dan 40wt%. Pengukuran sifat lentur, desorpsi dan absorpsi air dilakukan pada komposit PP dan PP/SDN. Hasil pengukuran densitas, bahan komposit dikelompokkan dalam papan serat kerapatan tinggi (PSKT) berdasarkan SNI 01-4449-2006. Dari variasi fraksi berat serat pada penelitian ini, kekuatan lentur tertinggi dimiliki oleh komposit PP/SDN40% dengan nilai (4,89 ± 0,37) MPa, meningkat sebesar 153,37% dibandingkan dengan PP murni. Nilai desorpsi dan absorpsi air masing-masing (1,08 ± 0,12) % dan (8,83 ± 3,35) %. Hasil pengamatan mikroskop optik menunjukkan bahwa komposit mengalami kegagalan matriks pada permukaan sampel sesudah uji lentur.

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ABSTRACTThe development of natural fiber reinforced composite research has shown significant results. Pineapple leaf fiber reinforced composites for non-structural application provide added value for Subang pineapple leaf fiber (PALF) waste. This study aimed to observe flexural strength, water absorption and desorption of composites which referred to the Indonesian National Standard (SNI). Alkali treatment on Subang PALF was performed to improve the interface bonding between PALF with polypropylene (PP), in which the PALF was soaked in 5% NaOH solution for 24 hours. Treated PALF and PP sheets were fabricated using compression molding (hot press) technique with the variation of fiber fraction to PP were 20 wt%, 30 wt% and 40 wt%. Flexural property, desorption and absorption water tests were conducted on PP and PP/PALF composites, and optical microscope (OM) observation was performed on the surfaces after the flexural test was conducted. The highest flexural strength was (4.89 ± 0.37) MPa, these values shown an increased respectively by (153,37) % compared to the pure PP. Then the desorption and the absorption water tests were (1,08 ± 0,12) % and (8,83 ± 3,35) % respectively. The morphology composites indicated that matrix failure it caused by there was a strong enough interface bond between the fiber and matrix.