Judul: Synthesis and Characterization of Viscose Made from OPEFB Fiber as a Semiconductor Material
Abstrak: Viskosa merupakan serat semi sintetis yang berasal dari proses regenerasi selulosa. Dalam penelitian ini, kandungan alfa selulosa TKKS yang tinggi diolah sebagai bahan baku dissolving pulp. Pembuatan pulp dilakukan menggunakan metode prahidrolisis kraft dengan variasi konsentrasi alkali aktif pada tahap pemasakan yaitu 15%, 20%, dan 25%, selanjutnya pulp diolah menjadi alkali selulosa kemudian dibentuk menjadi viskosa bersifat selulosa xantat. Penelitian ini bertujuan untuk mengetahui konsentrasi alkali aktif terbaik pada tahap pemasakan yang dapat menghasilkan pulp dan viskosa optimum. Pengujian yang dilakukan berupa pengujian kimia dissolving pulp, pengujian sifat listrik dengan LCR meter dan pengujian sifat permukaan dengan perhitungan energi bebas permukaan (SFE) viskosa. Hasil penelitian menunjukkan konsentrasi alkali aktif 25% menghasilkan pulp terbaik sesuai dengan SNI 938:2017. Konduktivitas listrik dan resistivitas yang dihasilkan dari ketiga sampel viskosa menunjukkan material yang bersifat semikonduktor. Variasi cairan uji SFE dengan air dan FFA memberikan sifat hidrofilik pada permukaan viskosa TKKS., Viscose is a semi-synthetic fiber obtained from a cellulose regeneration process. In this study, OPEFB which has a high alpha cellulose content, was processed as a raw material for dissolving pulp. The pre-hydrolysis kraft method is used to produce pulp with varying concentrations of active alkali used during the cooking stage are 15%, 20%, and 25%, which is subsequently processed into alkaline cellulose and converted into viscose with cellulose xanthate properties. The objective of this study is to determine the best concentration of active alkali in the cooking stage that can produce optimal pulp and viscose. The tests were carried out in the chemical testing of dissolving pulp, testing the electrical properties with an LCR meter and testing the surface properties by calculating the surface free energy (SFE) of OPEFB viscose. The results showed that the 25% active alkali concentration produced the best pulp according to SNI 938:2017. The electrical conductivity and resistivity of the three viscose samples show that the material is semiconducting. Variation of the SFE test liquid with water and FFA gave hydrophilic properties on the OPEFB viscose surface.
Keyword: Dissolving Pulp, OPEFB, Semiconductor, Surface Free Energy, Viscose

Judul: Modification of the Surface Properties of Oil Palm Empty Leaves (EFB) using the Delignification Method
Abstrak: Delignifikasi merupakan tahap awal yang bertujuan untuk mengurangi komposisi kimia non-selulosa di dalam serat TKKS. Delignifikasi dapat memutuskan ikatan non-selulosa dan melarutkan impuritas agar selulosa menjadi lebih mudah diurai. Tujuan penelitian ini dilaksanakan untuk memperoleh serat panjang TKKS dengan metode delignifikasi dan mengaplikasikannya dalam kain nonwoven serta mendapatkan kajian sifat mekanik. Proses pembuatan serat menggunakan pra-perlakuan sodium klorit-asam asetat (SC-AA) dan alkaline peroxide (AP), kemudian dilakukan pengujian komponen kimia menggunakan TAPPI. Hasil pengujian Sampel dikarakterisasi menggunakan alat TGA, FTIR, ASTM D 5035 dan ASTM D 5587. Hasil penelitian menunjukkan bahwa, berdasarkan uji termal (TGA) Sampel A6 memiliki kemampuan termal lebih baik dengan degradasi massa yang kecil 29% karena perlakuan AP mampu degradasi impuritas dan komposisi non-selulosa lebih tinggi dibandingkan perlakuan SC-AA. Sedangkan pada uji FTIR gugus fungsi pada bilangan gelombang 1030 cm-1 (C-O), 2300 cm-1 (O-H), 2900 cm-1 (C-H) menunjukkan terjadi penurunan persen transmitansi pada sampel A4 dan A6 dibandingkan kontrol. Hasil uji tarik dan sobek serat TKKS yang terbaik berdasarkan perlakuan alkaline peroxide yaitu pada nonwoven 4 lapis, semakin besar lapisannya maka kekuatan sobek dan tarik semakin tinggi. Delignifikasi terbaik adalah sampel alkaline peroxide (180 menit) dan berdasarkan uji mekanik serat TKKS nonwoven lapisan 4 dengan gramassi 1700 g/m2., Delignification is an initial step that aims to reduce the chemical composition of non-cellulose in the OPEFB fibers. Delignification can break non- cellulose bonds and dissolve impurities to make cellulose easier to break down. The purpose of this study was to obtain long fiber OPEFB by delignification method and apply it to non-woven fabrics and obtain a study of its mechanical properties. The fiber manufacturing process uses pre-treatment of sodium chlorite-acetic acid (SC-AA) and alkaline peroxide (AP), then testing the chemical components using TAPPI. Test results The samples were characterized using TGA, FTIR, ASTM D 5035 and ASTM D 5587 tools. The results showed that, based on the thermal test (TGA) Sample A6 had a better thermal ability with a small mass degradation of 29% because AP treatment was able to degrade impurity and non-cellulose composition was higher than SC-AA treatment. Whereas in the functional group FTIR test at wave numbers 1030 cm-1 (C-O), 2300 cm-1 (O-H), 2900 cm-1 (C-H) showed a decrease in the percentage of transmittance in samples A4 and A6 compared to controls. The best results of the tensile and tear test for OPEFB fibers based on alkaline peroxide treatment, namely on 4-layer nonwovens, the larger the layer, the higher the tear and tensile strength. The best delignification is alkaline peroxide sample (180 minutes) and based on mechanical test of 4 layer nonwoven OPEFB fibers with gramassiere 1700 g/m2.
Keyword: Alkaline peroxide (AP), Delignification, Chemical components, Nonwoven, OPEFB fibers, Sodium chlorite-acetic acid (SC-AA)

Judul: Posisi Filogenetik Kura-Kura Carettochelys Insculpta  (Reptillia: Testudinata)
Abstrak: Carettochelys insculpta is an endemic freshwater turtle of southern Papua and northern Australia. Phylogenetic position of this turtle is remain unresolved until now. Most of the research conducted show close relationships of C. insculpta and members of Trionychidae family. However, some of the research show distance between C. insculpta and members of Trionychidae family. This research is conducted to analyze phylogenetic relationship between C. insculpta and other members of Testudinata using 12S rRNA, 16S rRNA, and both gene as markers. DNA samples were obtained from three different organisms of C. insculpta. Two species used as outgroups were Alligator mississippiensis and Iguana iguana. Phylogenetic analysis was carried out using Neighbor-Joining method with Felsenstein 1981 (F81) modeltest. A polytomy tree of Testudinata was produced by using 12S rRNA gene. However, analysis using 16S rRNA and both genes as markers confirmed that C. insculpta was located between the Chelonidae and the Trionychidae family.
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