Pengaruh Penambahan Selulosa Nanokristal Dari Kulit Rotan Dengan Plasticizer Gliserol dan Co-Plasticizer Asam Sitrat Dalam Pembuatan Biokomposit Berbahan Dasar Pati Sagu (Metroxylon Sp)

The Effect of Nanocrystalline Cellulose from Rattan Biomass with
Glycerol as Plasticizer and Citric Acid as Co-Plasticizer Addition
Reinforced Sago Starch Biocomposite

ABSTRACT
Rattan biomass is the one bioresources of cellulose which contains 37,6% cellulose
content. The high cellulose contents of biomass rattan make it a source of
nanocrystalline cellulose as a filler in biocomposite. The aim of this research are to
obtain the characterization of nanocrystalline cellulose each Transmission Electron
Microscope (TEM), X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR).
And this research studied about the effect of filler loading of nanocrystalline cellulose
from biomass rattan, plasticizer glicerol and co-plasticizer citric acid addition on sago
starch biocomposite. The characterization are Scanning Electron Microscope (SEM),
Fourier Transform Infrared (FTIR), density, tensile strength, elongation at break, and
water uptake. Isolation of nanocrystalline cellulose from biomass rattan using
chemical and mechanical method by acid hydrolysis process with sulfuric acid 45%,
ultrasonication for 10 minutes, and filtration with dialysis membrane. Sago starch
biocomposites were prepared using a solution casting method, which includes 1–4
wt% nanocrystalline cellulose from rattan biomass as fillers, 10-40 wt% citric acid as
co-plasticizer and 30 wt% glycerol as plasticizer. The results of Transmission Electron
Microscope (TEM) and X-Ray Diffraction (XRD) characteristic of nanocrystalline

cellulose show diameter of nanocrystalline cellulose was 10-100 nm with around shape
and 84.46% of crystallinity index. Fourier Transform Infrared (FTIR) and chemical
composition analysis demonstrated that lignin and hemicellulose structures were
successfully removed. The results of mechanical properties were supported by
Scanning Electron Microscopy (SEM) showed that nanocrystalline cellulose (NCC)
was uniformly distributed on the sago starch matrix and FTIR of biocomposite with
nanocrystalline cellulose (NCC) and citric acid addition resulted in a sharp peak
absorption compared to bioplastics. This suggests that nanocrystalline cellulose (NCC)
and citric acid have been successfully binding to starch groups. The results showed the
highest density and tensile strength values were 0.28 gram/cm3 and 1,76 MPa obtained
at an additional of 3 wt% nanocrystalline cellulose (NCC) and 30 wt% citric acid. The
best value of elongation at break was 32,48% obtained at 1 wt% nanocrystalline
cellulose (NCC) and 30 wt% citric acid addition. The lowest water absorption was
14,81% obtained at an additional of 3 wt% nanocrystalline cellulose from rattan
biomass and 10 wt% citric acid.
Keywords: biocomposite, biomass rattan, citric acid, nanocrystalline cellulose, sago
starch.

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Universitas Sumatera Utara

Pengaruh Penambahan Selulosa Nanokristal Dari Kulit Rotan
Dengan Plasticizer Gliserol Dan Co-Plasticizer Asam Sitrat Dalam
Pembuatan Biokomposit Berbahan Dasar Pati Sagu
(metroxylon sp)

ABSTRAK
Selulosa merupakan sumber daya alami yang melimpah, salah satu sumber selulosa
adalah kulit rotan yang mengandung 37,6% selulosa, sehingga berpotensi untuk
digunakan sebagai bahan baku selulosa nanokristal (NCC) yang dimanfaatkan sebagai
pengisi dalam pembuatan biokomposit. Tujuan dari penelitian ini adalah untuk
mengetahui karakteristik selulosa nanokristal meliputi analisis TEM (Transmission
Electron Microscope), XRD (X-Ray Diffraction) dan FTIR (Fourier Transform
Infrared). Serta untuk mengetahui pengaruh penambahan selulosa nanokristal dari
kulit rotan dengan plasticizer gliserol dan co-plasticizer asam sitrat terhadap
karakteristik biokomposit pati sagu meliputi analisis SEM (Scanning Electron
Microscope), FTIR (Fourier Transform Infrared), densitas (density), kekuatan tarik
(tensile strength), pemanjangan saat putus (elongation at break), dan penyerapan air
(water uptake). Isolasi selulosa nanokristal menggunakan metode kimiawi dan
mekanik dengan proses hidrolisis asam menggunakan asam sulfat 45% dan

ultrasonikasi selama 10 menit dan dilanjutkan dengan proses filtrasi menggunakan
membran dialisis. Pembuatan biokomposit menggunakan metode casting, dimana
dilakukan penambahan bahan aditif ke dalam matriks pati sagu dengan penambahan
1-4 wt% selulosa nanokristal kulit rotan sebagai pengisi, 10-40 wt% asam sitrat
sebagai co-plasticizer dan 30 wt% gliserol sebagai plasticizer. Hasil analisis TEM
(Transmission Electron Microscope) dan XRD (X-Ray Diffraction) selulosa
nanokristal menunjukkan selulosa nanokristal memiliki diameter 10-100 nm dengan
kristalinitas 84,46%. Hasil analisis FTIR (fourier transform infrared) menunjukkan
bahwa hemiselulosa dan lignin telah berhasil dihilangkan. Hasil uji mekanik
selanjutnya didukung oleh analisis SEM (Scanning Electron Microscopy) yang
menunjukkan selulosa nanokristal (NCC) terdistribusi secara merata pada biokomposit
dan analisis FTIR (Fourier Transform Infrared) biokomposit dengan penambahan
selulosa nanokristal (NCC) dan asam sitrat menghasilkan puncak serapan yang tajam
dibandingkan dengan bioplastik. Hal ini menunjukkan bahwa selulosa nanokristal
(NCC) dan asam sitrat telah berhasil berikatan dengan gugus pati. Hasil analisis
densitas (density) dan kuat tarik (tensile strength) terbaik adalah 0,28 gram/cm3 dan
1,76 MPa yang diperoleh pada penambahan selulosa nanokristal (NCC) 3% dan asam
sitrat 30%. Nilai terbaik dari pemanjangan saat putus (elongation at break) dan
penyerapan air (water uptake) adalah 32,48% dan 14,81% yang diperoleh pada
penambahan 1% selulosa nanokristal (NCC) dan 30% asam sitrat.

Kata kunci : asam sitrat, biokomposit, kulit rotan, selulosa nanokristal, pati sagu.

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Universitas Sumatera Utara