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Properties of Cellulose Hydrogel from Kenaf Core Prepared via
Pre-cooled Dissolving Method
(Sifat Selulosa Hidrogel daripada Teras Kenaf Menggunakan Kaedah Pra-penyejukan)
HATIKA KACO1, SARANI ZAKARIA*1, NUR FAZLINDA RAZALI1, CHIN HUA CHIA1,
LINA ZHANG2 & SAAD MOHAMAD JANI3
1School of Applied
Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia
43600 Bangi, Selangor, D.E. Malaysia
2Department
of Chemistry, Wuhan University, China
3Malaysian
Agricultural Research and Development Institute (MARDI), Malaysia
Diserahkan: 18 September 2013/Diterima:
7 Disember 2013
ABSTRACT
Hydrogels were produced from cellulose derived from kenaf core powder with weight average molecular weight of
cellulose was 1.68 × 105 and
was dissolved in NaOH/urea solvent at -13oC.
To obtain the optimal dissolving parameters, different percentage of NaOH, urea and kenaf core
cellulose was used to study the degree of dissolution and formation of
hydrogel. From the results obtained, it was found that the ratio of 6% NaOH/4% urea and 2% cellulose produced a good hydrogel. UV-Vis
spectroscopy and XRD analysis were performed to analyze the
transparency and crystallinity index of the cellulose solution and hydrogel,
respectively. It showed that the hydrogel with the highest degree of solubility
gave highest transparency due to the reduction of cellulose crystallinity as a
result of the dissolution process. XRD analysis results showed the crystallinity
of cellulose from kenaf core decreased by 70% after
dissolution and hydrogel formation. Samples with 4% urea possess highest water
content of 73% and decreased with increasing urea content.
Keywords: Crystallinity; dissolution; hydrogel; kenaf core; transparency
ABSTRAK
Hidrogel telah berjaya dihasilkan daripada selulosa serbuk teras kenaf dengan didapati purata berat molekul selulosanya adalah 1.68 × 105. Selulosa ini kemudiannya dilarutkan dalam pelarut NaOH/urea pada suhu -13oC. Bagi mendapatkan parameter yang optimum, peratus NaOH, urea dan berat selulosa divariasikan. Hasilnya didapati bahawa nisbah 6% NaOH/4% urea dan 2% selulosa dapat menghasilkan hidrogel yang paling baik. Analisis spektroskopi UV-Vis dan XRD dijalankan untuk menganalisis ketelusan dan index kehabluran larutan selulosa dan hidrogel yang terhasil. Hidrogel dengan peratus kelarutan yang paling tinggi mempunyai ketelusan yang
paling baik. Ini adalah disebabkan oleh peratus kehabluran selulosa semakin berkurang disebabkan oleh hasil proses pelarutan yang dilakukan. Analisis XRD menunjukkan selulosa daripada teras kenaf mengalami pengurangan daripada segi kehabluran sebanyak 70% selepas proses pelarutan dan pembentukan hidrogel. Sampel dengan kandungan urea sebanyak 4% menunjukkan peratus kandungan air yang paling tinggi iaitu 73% dan menurun dengan peningkatan kandungan urea.
Kata kunci: Hidrogel; kehabluran; kelarutan; ketelusan; teras kenaf
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*Pengarang untuk surat-menyurat; email: szakaria@ukm.edu.my
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