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Cynthia L. Radiman
Departemen Kimia, FMIPA Institut Teknologi Bandung
Mathematics

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Pengaruh Media Perendam Terhadap Permeabilitas Membran Polisulfon Cynthia L. Radiman; Yuliany Yuliany; Veinardi Suendo
Jurnal Matematika & Sains Vol 7, No 2 (2002)
Publisher : Institut Teknologi Bandung

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Abstract

The performance of membrane separation processes can be generally expressed by membrane permeability and permselectivity. One of the important factors affecting membrane permeability in the filtration process of aqueous solution is membrane hydrophilicity. In this experiment, the effects of various soaking mediums, i.e. ethanol, isopropanol and butanol on the permeability of polysulfone membrane were studied. The results showed that soaking in ethanol gave the greatest effect proved by the drastic increase in permeability for membrane before and after soaking, i.e. from 263.57 L/m2.h to 645.49 L/m2.h. On the other hand, the membrane rejection against dextran T-500 before and after soaking in ethanol only showed a slight decrease from 96 % to 95 %. In addition, the contact angle between water and soaked-in-ethanol membrane gave the smallest value, i.e. 19.8°. The interaction between alcohol and soaked membrane is then considered as a reversible physical adsorption since the permeability reached its initial value after being soaked again in water for a long period. The experimental data showed that ethanol could enhance the permeability of polysulfone membrane by increasing the membrane hydrophilicity without giving any significant decrease in the membrane permselectivity.
Pengaruh Variasi Komposisi Amilosa terhadap Kemudahan Biodegradasi Poliuretan Eli Rohaeti; N. M. Surdia; Cynthia L. Radiman; E. Ratnaningsih
Jurnal Matematika & Sains Vol 8, No 4 (2003)
Publisher : Institut Teknologi Bandung

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Amylose had been used to synthesize polyurethanes. A mixture of polyethylene glycol (PEG) with a molecular weight 400 with amylose was reacted with diphenylmethane-4,4’-diisocyanate (MDI) at room temperature to produce polyurethanes. The precured polyurethanes were heat-pressed and PU sheets were obtained. Characterization of functional groups was determined by FTIR spectrophotometry and crystallinity was analyzed by using XRD. The hydrogen bonding index (HBI) of polyurethane samples increased with an increasing of amylose content. The addition of 15% (w/w) amylose decreased the degree of crystallinity of polyurethane. The films of polyurethanes were biodegraded by Pseudomonas aeruginosa in an liquid of Luria Bertani (LB) media at 37oC for 5, 10, 15, 20, 25, and 30 days, with the changing of media every 5 days. The result of weight loss percentace showed that all polymers may be biodegraded, with different biodegradation rate. The biodegradability (rate of weight loss) of polyurethanes by Pseudomonas aeruginosa increased when the amylose content in the polyurethane increased. The polyurethane product with 15% amylose – PEG400 – MDI had the highest biodegradability.
Co-Authors E. Ratnaningsih Eli Rohaeti N. M. Surdia Veinardi Suendo Yuliany Yuliany