Characterization and Properties of Chitosan-Filled Rubber Compuonds

Mohamed Shaari, Shazlin (2016) Characterization and Properties of Chitosan-Filled Rubber Compuonds. PhD thesis, Universiti Sains Malaysia.

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Abstract

Penggunaan bahan-bahan dari sumber boleh diperbaharui di dalam sebatian getah asli adalah sangat bermanfaat oleh kerana dapat meminimakan kos serta meminimakan pencemaran persekitaran disebabkan mempunyai sifat terbiodegradasi. Dengan tujuan itu, kajian ini dilaksanakan untuk melihat kebolehlaksanaan penggunaan kitosan sebagai pengisi dalam sebatian getah asli (NR). Dalam kajian ini, pengaruh pembebanan kitosan, kepelbagaian jenis getah, kepelbagaian jenis sistem pemvulkanan dan penggunaan agen pengganding silana terhadap sifat-sifat permatangan, sifat mekanikal dan fizikal dan kebolehdegradasi sebatian NR dikaji. Penyediaan sebatian getah asli terisi kitosan dengan pembebanan 0 – 40 bsg kitosan dilakukan dengan menggunakan mesin penggiling bergulung dua. Kajian ini menunjukkan bahawa penambahan kitosan telah mempertingkatkan sifat-sifat pematangan sebatian getah asli seperti mengurangkan masa pematangan lebih daripada 60% dengan hanya pembebanan 10 bsg kitosan. Sebaliknya, peningkatan pembebanan kitosan terbukti akan mengurangkan kekuatan, fleksibiliti dan hayat lesu sebatian getah. Begitu juga, penambahan kitosan dalam pelbagai jenis getah; NR, getah asli terepoksida (ENR) dan getah stirena-butadiena (SBR) dan penggunaan sistem pemvulkanan yang berbeza; pemvulkanan lazim (NR/CV), pemvulkanan separa-cekap (NR/semiEV) dan pemvulkanan berasaskan peroksida (NR/DCP) menunjukkan pola pengurangan sifat mekanikal yang sama pada tahap pembebanan kitosan yang lebih tinggi. Telah diperhatikan bahawa NR terisi kitosan mempamerkan sifat mekanikal dan fizikal tertinggi diikuti dengan ENR dan SBR terisi kitosan. Begitu juga, NR/CV terisi kitosan menunjukkan sifat-sifat yang lebih baik berbanding dengan NR/semiEV dan NR/DCP terisi kitosan. Penambahan 3-Aminopropiltrietoksilana (APTES) menunjukkan kesan positif ke atas sebahagian besar daripada sifat-sifat NR terisi kitosan. Ejen gandingan silana telah meningkatkan penyebaran dan lekatan kitosan kepada matriks NR dan membawa kepada sifat-sifat yang lebih baik. Pendedahan sampel kepada cuaca semula jadi dan penanaman di dalam tanah menyebabkan sampel mengalami pengurangan progresif dalam kekuatan tensil, pemanjangan pada takat putus dan modulus tensil dengan tempoh pendedahan yang berpanjangan. Perubahan kimia didapati berlaku dalam sampel ujian selepas terdedah kepada kedua-dua keadaan. Indeks karbonil yang diperolehi daripada spektrum FTIR mengesahkan bahawa kemerosotan dan degradasi berlaku semasa pendedahan terhadap cuaca semula jadi dan penanaman di dalam tanah. Kajian mikrograf SEM mengesahkan kemerosotan permukaan dan degradasi yang teruk berlaku pada sebatian NR terisi kitosan dan meningkat dengan pembebanan kitosan, tempoh pendedahan seterusnya mengakibatkan kadar kehilangan berat yang tinggi. Secara kesimpulannya, kitosan boleh digunakan dalam sebatian getah sebagai pengisi bukan pengukuh untuk tujuan tertentu seperti pengubahsuaian sifat-sifat pematangan, mengurangkan penggunaan pengisi komersial yang mahal dan untuk mencetus sifat terbiodegradasi kepada sebatian getah. ________________________________________________________________________________________________________________________ Extending the utilization of renewable resources based reinforcements in natural rubbers are highly beneficial due to the fact that the utilization of renewable resources fillers is inexpensive while at the same time, they could minimize the environmental pollution owing to the characteristic biodegradability. Therefore, this study was carried out to look into the feasibility of using chitosan as filler in natural rubber (NR). In this study, the influence of chitosan loading, different types of rubber, different types of vulcanising system and the use of silane coupling agent on the cure characteristics, mechanical and physical properties and degradability of the NR compounds were studied. The chitosan-filled NR compounds incorporated with 0 – 40 phr chitosan was prepared using the laboratory two-roll mill. The study showed that the incorporation of chitosan enhanced the cure characteristics of the NR compounds such as reducing the cure time by more than 60% with the incorporation of 10 phr chitosan. In contrast, the increasing chitosan loading proves to be detrimental to the strength, the flexibility and fatigue life of the rubber compounds. Likewise, the incorporation of chitosan in different types of rubber; NR, Epoxidized natural rubber (ENR) and Styrene-butadiene rubber (SBR) and the use of different cure systems; conventional vulcanization (NR/semiEV) and peroxide based vulcanization (NR/DCP) systems depicts similar trends of declining mechanical properties at higher chitosan loadings. It was observed that chitosan-filled NR vulcanizates displays the highest mechanical and physical properties followed by chitosan-filled ENR and chitosan-filled SBR. Similarly, the chitosan-filled NR/CV vulcanizates exhibit better properties compared to the NR/semiEV and NR/DCP vulanizates. The addition of 3-Aminopropyltriethoxysilane (APTES) showed a positive effect on most of the properties of the chitosan-filled NR vulcanizates. The silane coupling agent has effectively improved the chitosan dispersion and the adhesion of chitosan to the NR matrix and leads to better properties. Upon exposure to natural weathering and soil burial, the exposed samples experienced a progressive decay in tensile strength, elongation at break and tensile modulus with prolonged exposure period. Chemical changes were found to occur in the test samples after exposure to both conditions. Carbonyl indices obtained from the FTIR spectra confirmed that deterioration and degradation occurred during natural weathering and soil burial. The SEM micrographs studies proved that the severity of the surface deterioration and degradation of vulcanizates increased with chitosan loading and exposure period thus, results in higher rate of weight loss. In conclusion, chitosan particles can be employed in rubber compounds as non-reinforcing filler to serve certain purpose such as to modify the cure properties, to reduce the use of expensive commercial filler and to impart biodegradability to the rubber compounds.

Item Type: Thesis (PhD)
Additional Information: Full text ias available at http://irplus.eng.usm.my:8080/ir_plus/institutionalPublicationPublicView.action?institutionalItemId=2036
Subjects: T Technology
T Technology > TN Mining Engineering. Metallurgy > TN263-271 Mineral deposits. Metallic ore deposits. Prospecting
Divisions: Kampus Kejuruteraan (Engineering Campus) > Pusat Pengajian Kejuruteraan Bahan & Sumber Mineral (School of Material & Mineral Resource Engineering) > Thesis
Depositing User: Mr Mohd Jasnizam Mohd Salleh
Date Deposited: 11 Jun 2018 02:53
Last Modified: 11 Jun 2018 02:53
URI: http://eprints.usm.my/id/eprint/40737

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