PENGARUH PENAMBAHAN SERAT PURUN TIKUS (Eleocharis dulcis) PADA KOMPOSIT POLIESTER TERHADAP SIFAT MORFOLOGI

Abstract

Masyarakat di Desa Stambul Jaya, Kabupaten Aceh Tenggara, memanfaatkan tanaman purun tikus (Eleocharis dulcis) sebagai bahan baku untuk pembuatan kerajinan tangan. Produk-produk yang dihasilkan meliputi tikar, topi, keranjang belanja, tas, dan bakul. Serat purun juga dapat diolah menjadi papan komposit. Dalam penelitian ini, pembuatan material komposit menggunakan metode pengepresan cetakan dengan ukuran 20x20x0,5 cm. Penelitian ini mempelajari pengaruh variasi komposisi serat purun (5%, 10%, dan 15%) terhadap resin poliester, serta susunan serat (sejajar, acak, dan anyaman). Analisis sifat komposit meliputi gugus fungsi dan morfologi menggunakan FTIR dan SEM. Hasil analisis menunjukkan bahwa perlakuan terhadap serat purun dapat menurunkan kandungan lignin dan hemiselulosa. Spektrum FTIR juga mengindikasikan adanya vibrasi C=C pada cincin aromatik dan pergeseran vibrasi C-O (glikosida) pada beberapa sampel komposit. Sampel sejajar 10% menunjukkan adanya ikatan Si- O-C dari Vinyltrimethoxysilane pada 744cm-1. Hasil SEM sampel sejajar 5% tidak sejajar, karena serat purun tidak teratur saat pencetakan komposit akibat poliester, sehingga cetakan tidak penuh. Sampel acak 5% berbentuk tidak teratur, tipis, dan saling tumpang tindih, sehingga tidak kuat dan mudah patah. Anyaman 5% menunjukkan poliester di sela-sela serat purun, karena jumlah serat purun sedikit saat pencetakan komposit.

Kata Kunci: Serat purun tikus (Eleocharis dulcis), komposit, poliester, sifat morfologi.

People in Stambul Jaya Village, Southeast Aceh Regency, use the purun Tikus plant (Eleocharis dulcis) as raw material for making handicrafts. The products produced include mats, hats, shopping baskets, bags and baskets. Purun fiber can also be processed into composite boards. In this research, composite material was made using a mold pressing method with a size of 20x20x0.5 cm. This research studied the effect of variations in purun fiber composition (5%, 10%, and 15%) on polyester resin, as well as fiber arrangement (parallel, random, and woven). Analysis of composite properties including functional groups and morphology using FTIR and SEM. The results of the analysis show that treatment of purun fiber can reduce the lignin and hemicellulose content. The FTIR spectrum also indicated the presence of C=C vibrations in aromatic rings and shifts in C-O (glycoside) vibrations in several composite samples. The 10% aligned sample shows the presence of Si-O-C bonds from Vinyltrimethoxysilane at 744cm-1. The SEM results of the parallel samples were 5% not parallel, because the purun fibers were irregular when printing the composite due to the polyester, so the mold was not full. The 5% random samples are irregularly shaped, thin, and overlap each other, so they are not strong and break easily. 5% webbing shows polyester in between the purun fibers, because the amount of purun fibers is small when molding the composite.

Keywords: Rat purun (Eleocharis dulcis) fiber, composite, polyester, morphological properties.