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PRELIMINARY STUDY OF EMULSION COPOLYMERIZATION OF STYRENE ON NATURAL RUBBER LATEX Sondari, Dewi; Haryono, Agus; Ghozali, M
Prosiding Seminar Nasional Sains Dan Teknologi Fakultas Teknik Vol 1, No 1 (2010): PROSIDING SEMINAR NASIONAL SAINS DAN TEKNOLOGI 1 2010
Publisher : Prosiding Seminar Nasional Sains Dan Teknologi Fakultas Teknik

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Abstract

Polystyrene-graft-natural rubber was prepared by emulsion copolymerization using potassium persulfate and sodium dodecyl sulfate as an initiator and emulsifier respectively. Ratios of monomer styrene to natural rubber were 80:20; 60:40; 50:50, and 40:60 % (v/v). Grafting efficiency could be investigated by extracting the dried sample with methyl ethyl ketone and petroleum ether and then weighting the left over dried sample. The copolymers composition of the polystyrene-graft-natural rubber was obtained using 1H-NMR spectroscopy and  the occurrence of styrene-graft-natural rubber was identified by FTIR spectroscopy. Keywords: Graft Efficiency, natural rubber, emulsion polymerization, copolymerization.
SYNTHESIS OF CATIONIC CELLULOSE AS POLYMERIC SURFACTANTS Sondari, Dewi; Haryono, Agus
Prosiding Seminar Nasional Sains Dan Teknologi Fakultas Teknik Vol 1, No 1 (2010): PROSIDING SEMINAR NASIONAL SAINS DAN TEKNOLOGI 1 2010
Publisher : Prosiding Seminar Nasional Sains Dan Teknologi Fakultas Teknik

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Abstract The synthesis of cationic cellulose dissolved in water was conducted at 50o for 2 hours continued at temperature 76oC for 15 minutes in a glass reactor. The cationic cellulose  was synthesized through one-step substitution reaction The chemical composition of cationic cellulose was analyzed by FTIR (Fourier-Transformed Infra-Red). The successful conjugation onto cellulose chain confirmed by 1H NMR (Nuclear Magnetic Resonance). Water solubility of cationic cellulose product was measured using UV-Visible spectrophotometer at 600 nm. Keywords: Cationic cellulose, polymeric surfactants, water- soluble polymer, 1H NMR, FTIR
Determination of The Active Asiaticoside Content in Centella asiatica as Anti-Cellulite Agent Sondari, Dewi; Harmami, Sri Budi; Ghozali, M; Randy, Ahmad; S, Athanasia Amanda; Irawan, Yan
Indonesian Journal of Cancer Chemoprevention Vol 2, No 2 (2011)
Publisher : Indonesian Research Gateway

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Abstract

Centella  asiatica  accumulates  large  quantities  of  pentacyclic  triterpenoid saponins,  collectively  known  as  centelloids.  These  terpenoids  include  asiaticoside, centelloside,  madecassoside,  brahmoside,  brahminoside,  thankuniside,  sceffoleoside, centellose, asiatic-, brahmic-, centellic- and madecassic acids. Preparations of C. asiatica are  used  in  traditional  and  alternative  medicine  due  to  the  wide  spectrum  of pharmacological  activities  associated  with  these  secondary  metabolites,  such  as anticellulite agent. Asiaticoside was found in Centella asiatica. In this present study, the asiaticoside was extracted using methanolic and ethanolic solvent. Determination of the asiaticoside  content  in  the  extract  was  conducted  with  High Performance  Liquid Chromatography (HPLC), Thin Layer Chromatography (TLC), and Fourier Transform Infra Red (FTIR). Samples of C.  asiatica used in this study came from three different plantation  areas,  Bogor,  Lembang  and  Solo.  Asiaticoside  content  in  the  methanolic extract  from  Bogor,  Lembang,  and  Solo  samples  were  2.82%;  2.68%;  and  2.8% respectively. Asiaticoside in ethanolic extract from Bogor, Lembang, and Solo samples were 2.79%; 2.75%; and 2.91% respectively. Two way ANOVA study showed that there was  significant  difference  between  types  of  solvent  used  in  extraction  and  the asiaticoside  content  in  the  obtained  extract,  significant  difference  between  varied plantation area and obtained asiaticoside content, and significant difference between interactions of different solvent with different plantation area.     Key words: Centella asiatica, asiaticoside, anticellulite, medicine, metabolites  
PREPARATION OFPOLYURETHANE MICROCAPSULE USING 1,3 PROPANEDIOLAS THE POLYOL COMPONENT. Randy, Ahmad; Sondari, Dewi; Triwulandari, Evi; Handayani, Murni
Jurnal Sains Materi Indonesia Vol 12, No 1: OKTOBER 2010
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

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Abstract

PREPARATION OFPOLYURETHANE MICROCAPSULE USING 1,3 PROPANEDIOLAS THE POLYOL COMPONENT. Self-healing property is the ability of a material to heal damages automatically and autonomously. Its application would be ranged from paint coating, anti corrosion coating, space-shuttle material, construction (concrete) and automotive. Extrinsic self healing requires self healing agent preembedded or incorporated into polymer matrix that would be released and close the damage in the polymer system, where the polymer itself is not healable. Healing agents are encapsulated or embedded into the material prior application. Example of monomer encapsulated to give self healing property is isophorone diisocyanate (IPDI) encapsulated in polyurethane shell. In this study, we studied the possibility of 1,3 propanediol, that can be derived from palm oil as polyol monomer for polyurethane microcapsule shell containing IPDI or stannous octoate as a self healing agent. Microcapsule in this study was prepared by interfacial polymerization technique to form IPDI monomer in polyurethane shell. FT-IR analysis show that polyurethane prepolymer produced still have unreacted isocyanate group necessary for interfacial polymerization of polyurethane. Morphological analyses of the microcapsule products show that the products have spherical shapes with smooth surface and some with wrinkled surface. The particle sizes were ranged from 40.29 to 526.80 ?m.
SISTESA NANOPARTIKEL PERAK DAN POTENSI APLIKASINYA Haryono, Agus; Sondari, Dewi; Harnami, Sri Budi; Randy, Muhammad
Jurnal Riset Industri Vol 2, No 3 (2008):
Publisher : Badan Penelitian dan Pengembangan Industri

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Tulisan ini menuturkan beberapa metode sintesis nanopartikel perak yang sudah dilakukan. Salah satu metode sintesa nanopartikel perak yang dilakukan  adalah dengan metode reduksi kimia dari larutan perak nitrat potensi aplikasi nanopartikel perak antara lain sebagai katalis, detektor sensor optik dan agen antimikroba. Salahsatu apalikasi nanopartikel perak yang sudah banyak di pasarkan adalah produk dengan antimikroba. Karena produk komersial yang mengunakan nanopartikel perak sudahcukup beredar di pasaran , maka dilakukan kajian menyeluruh terhadap sisi keamanan terhadap kesehatan dan likungankata kunci :  nanopartikel perak, metode sintesa, aplikasi, agen antimikroba
SOLID ACID CATALYST OF MESOPOROUS ALUMINA-TITANIA MODIFIED GEL AND AEROGEL FOR ESTERIFICATION OF OF FATTY ACID. Tursiloadi, Silvester; Sondari, Dewi
Alchemy Jurnal Penelitian Kimia Vol 3, No 2 (2004)
Publisher : Alchemy Jurnal Penelitian Kimia

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Abstract

Three types of TiO2.Al2O3 gels ([TiO2]/[ Al2O3]=1/4 in mol) wre prepared by hydrolysis of Al(OC4H9sec)3and Ti(OC3H7iso)4 in an n-propanol solution with acid catalyst. Their physical properties and catalytic on the formation of polyethylene glycol ester were investigated. The wet gels were dried (Xerogel), immersed in surfactant solution before dying (Modified Gel), or supercritically extracted with CO2 at 60oC and 24 Mpa for 2h (Aerogel). The pore size and pore volume of these gels hardly decreased after calcinations at 800oC, atlhough those values of the xerogel remarkably decreased after calcination up to 800oC. The thermal stability of the microstructure of mesoporous titania-alumina is improved by surfactant immersion of supercritical extraction. The aerogel had the highest catalytic activity for the reaction of polyethylene glycol and stearic acid. The effects preparation methods on the microstructure and catalytic activity of the gels were disccussed.
STUDI AWAL PENGARUH METODE EKSTRAKSI TERHADAP RENDEMEN DAN KADAR ASIATICOSIDE DARI CENTELLA ASIATICA (L) URB Sondari, Dewi; Irawadi, Tun Tedja; Setyaningsih, Dwi; Tursiloadi, Silvester
Jurnal Sains Materi Indonesia Vol 17, No 3: APRIL 2016
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (224.213 KB) | DOI: 10.17146/jsmi.2016.17.3.4193

Abstract

STUDI AWAL PENGARUH METODE EKSTRAKSI TERHADAP RENDEMEN DAN KADAR ASIATICOSIDE DARI CENTELLA ASIATICA (L) URB. Proses ekstraksi Centella asiatica (L) Urb dengan metode maserasi, sonikasi, sokletasi dan CO2 superkritik telah dilakukan. Pengaruh proses ekstraksi terhadap rendemen dan kadar asiaticoside dari Centella asiatica (L) Urb (pegagan) telah dipelajari. Hasil dari perhitungan rendemen asiaticoside terlihat bahwa kandungan asiaticoside (% berat) dari proses ekstraksimaserasi, sonikasi, sokletasi dan CO2 superkritik berturut-turut sebagai berikut: 6,723%; 0,187%; 3.648%dan 9,24%. Rendemen asiaticoside paling tinggi diperoleh dari teknologi ekstraksi CO2 superkritik, karena teknologi ini dilakukan pada tekanan dan suhu tertentu sehingga kualitas hasil ekstraksi ditentukan oleh seberapa kritis penggunaan tekanan dan suhunya. Karena pada kondisi ini, selain mengubah densitas CO2, juga berpengaruh terhadap kelarutan dan selektivitas dari zat yang akan terekstrak. Semakin tinggi tekanan dan kelarutan, total hasil ekstraksi akan semakin tinggi. Untukmengetahui adanya senyawa asiaticoside dalam Centella asiatica (L) Urb (pegagan) digunakan analisis HPLC. Dari hasil analisis kromatogram bahwa ada dua puncak yang terdeteksi, dan secara kualitatif senyawa asiaticoside yang diperoleh denganmenggunakan ekstraksi CO2 superkritik lebih tinggi kadarnya dibanding metode ekstraksi lainnya, karena teknologi proses ekstraksi CO2 superkritik memanfaatkan kekuatan pelarut dan sifat fisik dari komponenmurni atau campuran, sehinggamudahmelakukan penetrasi ke dalam dinding material yang di ekstrak dan melarutkan komponen senyawa aktif secara selektif dengan kualitas produk tinggi dan tidakmengandung residu pelarut sehingga lebih murni.
SYNTHESIS OF POLYURETHANE MICROCAPSULE USING INTERFACIAL POLYMERIZATION AS SELF HEALING COATING MATERIAL Septevani, Athanasia Amanda; Triwulandari, Evi; Sondari, Dewi
Widyariset Vol 15, No 2 (2012): Widyariset
Publisher : LIPI-Press

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Abstract

Polyurethane microcapsule had been made as self healing coating material. Polyurethane microcapsule synthesis had been conducted by interfacial polymerization both spontaneous polymerization and prepolymer polyurethane polymerization using glycerol as renewable palm oil polyol. Based on FTIR-Spectra showed the functional group of polyurethane formed both spontaneous and prepolymer polyurethane polymerization. Polyurethane microcapsule formed was in spherical form. The particle size prepared by spontaneous polimerization was smaller than particle prepared by prepolymer polymerization at range 20,51±12,7 and 139,2±72,3 μm respectively.
ANALISIS FAKTOR YANG MEMPENGARUHI INOVASI PRODUK NANOENKAPSULASI EKSTRAK PEGAGAN SEBAGAI SEDIAAN UNTUK MENGATASI SELULIT Sondari, Dewi; Maarif, M. Syamsul; Arkeman, Yandra
TEKNIK INDUSTRI Vol 3, No 1 (2013): Volume 3 No 1 Maret 2013
Publisher : TEKNIK INDUSTRI

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Innovation is a research, development, and/or engineering which aims to develop thepractical application of values and context of new knowledge, or new ways to apply science andtechnology that has existed in the product or production process. Anti-cellulite innovationdevelopment based on market opportunities, goals and objectives nanoencaptulation producean anti-cellulite product using nano technology. Factors thought to influence innovation incompanies such as leadership styles, personal characteristics and dynamics of the environmentand the user market factors. In an innovation planning of nanoencaptulation should attention tothe functional aspects of a component, part of the whole system works. The main purpose offunctional analysis and design stage is to define the interaction of each component with eachother.
MODIFIKASI KARET ALAM MENJADI BAHAN ELASTOMER TERMOPLASTIK Suhardjo, Kuntari Adi; Basuki, Ariyadi; ., Surasno; Randy, Ahmad; Sondari, Dewi
Jurnal Riset Industri Vol 5, No 3 (2011): Peningkatan Nilai Tambah dan Produktivitas Industri
Publisher : Badan Penelitian dan Pengembangan Industri

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Abstract

Karet alam  bersifat elastomer dan termoseting, sehingga sulit  untuk dibentuk dan tidak dapat didaur ulang., Modifikasi karet alam menjadi bahan elastomer termoplastik dimaksudkan untuk memperoleh bahan yang mudah dicetak  menjadi  produk  jadi   dan  dapat  dapat  didaur  ulang  sehingga  tidak  merusak  lingkungan.   Untuk mendapatkan teknologi pembuatan elastomer termoplastik dari karet alam  telah dilakukan percobaan  dengan metoda pencangkokan (grafting)   secara polimerisasi emulsi antara karet alam lateks dengan monomer stirena dan metil metakrilat. Polimerisasi emulsi dilakukan pada suhu 65°C selama 6 jam. Perbandingan komposisi karet alam lateks dan monomer di variasi:  80:20; 70:30; 60:40; 50:50 (% berat) dengan komposisi monomer stirena dan metil metakrilat   1:1, menggunakan dua jenis inisiator yaitu potassium persulfat 2 % berat atau ammonium peroksodisulfat divariasi 2, 2,5, 5 % berat serta emulsifier sodium dodesil sulfat divariasi: 0, 1, 1,5,  2, 5 % berat. Dari hasil analisa 1 H NMR dan FTIR terlihat bahwa proses cangkok monomer stirena dan metil metakrilat telah terjadi pada tulang punggung karet alam. Puncak pada frekuensi 833 cm -1 menunjukkan pita RzC=CHR, frekuensi 1743 dan 1519 cm-1menunjukkan pita C=O (gugus karbonil dari metil metakrilat) dan pita C=C (cincin benzena dari stirena). Efisiensi cangkok maksimum sebesar 97,60% diperoleh  pada komposisi 70% karet alam lateks dan 30% monomer dimana komposisi monomer antara stirena dan metil metakrilat adalah 1: 1 menggunakan inisiator potasium persulfat 2% dan emulsifier sodium dodesil sulfat 1%.Kata  kunci: Elastomer termoplastik, kopolimer cangkok, karet alam lateks, stirena, metilmetakrilat.