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All Journal Saintia Kimia JOURNAL OF CHEMICAL NATURAL RESOURCES (JCNaR)
Darwin Yunus Nasution
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Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Materials Science & Nanotechnology

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PENENTUAN BERAT MOLEKUL DAN DERAJAT POLIMERISASI α – SELULOSA YANG BERASAL DARI ALANG-ALANG (Imperata cylindrica) DENGAN METODE VISKOSITAS Rudnin Habibah; Darwin Yunus Nasution; Yugia Muis
Saintia Kimia Vol 1, No 2 (2013): SAINTIA KIMIA
Publisher : USU

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (595.681 KB)

Abstract

Research of the determination of molecular weight and degree of polymerization α-cellulose from seagegrass (Imperata cylindrica) by viscosity method had been done. To obtain the      α-cellulose, it was done using delignification process. Furthermore, the α-cellulose was characterized by infra red spectrum (FTIR) testing by compared with the infra red spectrum of α-cellulose standard. The α-cellulose viscosity was measured by using Ostwald viscometer and measurement of molecular weight and degree of polymerization based on Mark-Kuhn-Houwink equation. The results showed that the molecular weight and degree of polymerization of the α-cellulose from seagegrass (Imperata cylindrica) were 8.242,7g/mol and 45,8, respectively with the percentage of seagegrass α-cellulose was 45%. Keywords: seagegrass (Imperata cylindrica), viscosity intrinsic, molecular weight, degree of polymerization
Preparation and Characterization of Superabsorbents Based on Durian Seed Starch (Durio zibethinus) and Carboxymethyl Cellulose Using Citric Acid Crosslinking Nasution, Darwin Yunus; Pondang , Siska
Journal of Chemical Natural Resources Vol. 6 No. 2 (2024): Journal of Chemical Natural Resources
Publisher : Talenta Publisher

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32734/jcnar.v6i2.18146

Abstract

Superabsorbents are materials that can absorb a liquid beyond its initial volume. Natural polymer-based superabsorbents can be obtained by combining CMC and durian seed starch. The combination of these two materials was cross-linked using varying amounts of citric acid: 0.0 grams, 0.2 grams, 0.4 grams, and 0.6 grams. The resulting superabsorbent has a cross-linking degree of about 41%, shows the presence of OH and CH groups, has a rough and dense surface, and a maximum water absorption capacity of 4130% with a water absorption rate of 41.3 g/g. Durian seed starch has potential as a superabsorbent material.
Fabrication of Biodegraded Composite from Polypropylene, Polypropylene Grafted Maleic Anhydride, and Chempedak Seed (Artocarpus integer) Starch Nasution, Darwin Yunus; Jumirah; Siregar, Amir Hamzah
Journal of Chemical Natural Resources Vol. 3 No. 2 (2021): Journal of Chemical Natural Resources
Publisher : Talenta Publisher

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (513.374 KB) | DOI: 10.32734/jcnar.v3i2.9344

Abstract

Fabrication of biodegraded composite from polypropylene, polypropylene grafted maleic anhydride, and chempedak seed (Artocarpus integer) starch has been conducted. The stages were prepared starch of Cempedak seed, grafting process of maleic anhydride on polypropylene, and fabrication of composite with a composition ratio of PP: PP-g-MA: starch of chempedak seed (9.5:0.5:0.1)g, (9.5:0.5:0.2)g, (9.5:0.5:0.3)g, (9.5:0.5:0.4)g, (9.5:0.5:0.5) g, and PP: starch of chempedak seed (10:2)g. The composites obtained were characterized using tensile strength and elongation testing, surface morphology analysis by SEM, analysis in nature with the ability to decompose by biodegradable test, and functional groups analysis by FTIR spectroscopy. The results showed that the biodegradable composites have the best properties in the ratio of PP: PP-g-MA: starch of chempedak seed (9.5:0.5:0.1)g with the test results of tensile strength was 28.743 N/m2, and also the SEM results show that flat surface and improved homogeneity, and strong group interactions as well as having good biodegradable properties.
Characterization of Biodegradable Composites from Polypropylene, Polypropylene Grafted Maleic Anhydride, and Durian Seed Starch Nasution, Darwin Yunus; Fitri, Rizka Meilia; Siregar, Amir Hamzah
Journal of Chemical Natural Resources Vol. 4 No. 1 (2022): Journal of Chemical Natural Resources
Publisher : Talenta Publisher

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (598.965 KB) | DOI: 10.32734/jcnar.v4i1.9359

Abstract

The characterization of biodegradable composite from durian seed starch that is mixed polypropylene, and polypropylene grafted maleic anhydride has been done. The stages of this preparation were, the first had prepared durian seed starch, the second had the process of grafting maleic anhydride into polypropylene and the third had made of composite with the composition of PP:PP-g-MA: DSS (7:0.5:0.2); (7:0.5:0.3); (7:0.5:0.4); (7:0.5:0.5); (7:0.5:0.6) (w/w). The biodegradable composites obtained were characterized by tensile strength, surface morphology analysis by SEM, differential thermal analysis (DTA), analysis in nature with the ability to decompose biodegradable test, and functional groups analysis by FTIR spectroscopy. The results showed that the biodegradable composites have the best properties in the ratio of PP:PP-g-MA: DSS was (7:0.5:0.5) (w/w) with the test results of tensile stress is 12.556 N/m2, and the elongation is 8.600%, the images on a few flat surfaces and improved homogeneity, temperature change, and strong group interactions as well as having good biodegradable properties.
Determination of Maximum Adsorption Capacity of Chitosan and Carboxymethyl Chitosan on the Absorption of Metal Ions Cr (VI) Based on the Langmuir Equation Nasution, Darwin Yunus; Siregar, Amir Hamzah; Rokhmayanti, Etika
Journal of Chemical Natural Resources Vol. 6 No. 1 (2024): Journal of Chemical Natural Resources
Publisher : Talenta Publisher

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32734/jcnar.v6i1.16212

Abstract

A study has been conducted to investigate the adsorption of chrom (VI) metal ions by hand chitosan and carboxymethyl chitosan. This research aimed to examine the adsorption capacity of chitosan and carboxymethyl chitosan and determine the applicability of the Langmuir isotherm adsorption method for adsorbing Cr (VI) metal ions utilizing these materials. Chitosan was chemically treated with a 40% NaOH solution and monochloroacetic acid, dispersed in 2-propanol at room temperature for 10 h. This reaction resulted in the formation of carboxymethyl chitosan. FT-IR analyzed the functional group of carboxymethyl chitosan. The adsorption process was conducted using a standard solution with varying concentrations of Cr6+, specifically 5, 10, 15, and 20 mg/L. The concentration of Cr6+ adsorbed was measured using an Atomic Absorption Spectrophotometer. The findings demonstrated that carboxymethyl chitosan exhibited the maximum capacity for adsorbing chrom metal ions, with a mass of 0.9179 mg/g carboxymethyl chitosan at a concentration of 20 ppm. Chrom (VI) metal ion adsorption by carboxymethyl chitosan follows the Langmuir equation with an R2 value greater than 0.9. The maximum adsorption capacity of carboxymethyl chitosan is 1.16 mg/g, which is higher compared to chitosan's capacity of only 0.60 mg/g.
Effect of Clay Composition and Human Haircut Waste on Mechanical Properties Mechanical Properties of Epoxy Resin Composites Nasution, Darwin Yunus; Delfis, Muhammad
Journal of Chemical Natural Resources Vol. 6 No. 1 (2024): Journal of Chemical Natural Resources
Publisher : Talenta Publisher

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32734/jcnar.v6i1.16220

Abstract

The impact of human haircut waste and the nature of clay soil on the mechanical characteristics of epoxy resin composites has been studied. This study utilizes clay sourced from Wonosari Village, Deli Serdang Regency. The clay was pulverized using a pestle and mortar until it reached a smooth consistency. It is then filtered through a 200 mesh screen and subjected to drying in an oven at a temperature of 105℃ for around 3 h until the water content is completely evaporated. Finally, the dried clay stored in a desiccator. The clay powder was subjected to ball milling for 40 h at 350 rpm. The resulting particle size, determined by particle size analysis (PSA), was found at 0.764 µm. Next, the human haircut waste obtained from the surrounding campus of Universitas Sumatera Utara was prepared by separating the hair from fine hair and washing it clean. Clay soil powder and human hair cut waste are used as fillers, and some variations of epoxy resin mixtures are used. Morphological SEM analysis shows that clay and human haircut waste can be distributed evenly on epoxy resin composites. Testing of water absorption and mechanical properties of the board based on SNI 01-449-2006 standards include the test of dry bending strength (MoR) and the mode of flexural elasticity (MoE) obtained the optimum composition (50: 50: 1: 1) g against the epoxy resin mixture, waste human haircut, and clay soil obtained the water absorption test results of 1.64% with a value of MoE 36789.03 kgf /cm2 and a value of MoR 664,41 kgf/cm2. Test results of mechanical properties and water absorption have fulfilled the SNI 01-449-2006 quality standards for composite boards.
Co-Authors Amir Hamzah Siregar, Amir Hamzah Delfis, Muhammad Fitri, Rizka Meilia Jumirah Pondang , Siska Rokhmayanti, Etika Rudnin Habibah Yugia Muis