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Abstrak :
Sebagian besar aspal pertamina hanya digunakan sebagai pelapis jalan raya. Hal ini disebabkan terbatasnya jenis dan kelas yang dihasilkan, padahal dengan sedikit modifikasi aspal bisa digunakan diberbagai bidang. Untuk itu perlu dilakukan modifikasi agar aspal pertamina mempunyai nilai tambah yang lebih tinggi. Pada penelitian ini dilakukan modifikasi aspal pertamina dengan mencampurnya dengan aspal buton kemudian dijadikandalam bentuk emulsi. Penelitian ini dimulai dengan menumbuk dan mengekstrak aspal buton, setelah itu dicampur dengan aspal pertamina dengan berbagai variasi konsentrasi, kemudian diemulsikan dengan sabun (sodium oleat). Aspal emulsi yang terbentuk dilakukan uji spesifikasi yang sesuai dengan aspal emulsi lapisan pelindung lIogam dan lapisan pelindung atap menurut ASTM. Campuran aspal pertamina dengan aspal buton dapat meningkatkan kualitas aspal emulsi.

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Part of pertamina asphalt is only used as road coating. This is because of limited kind and grade produced, whereas by only scanty modifications, it can be used in various sectors. For that reason, modifications are needed so that the pertamina asphalt may possess a higher additional value. In this research, modifications of pertamina asphalt were done by blending with buton asphalt and transformed into emulsion form. This research begined with grinding and extracting buton asphalt, then, it was blended with pertamina asphalt by applying various concentrations, and after that, it was emulsified with soap (sodium oleate). The ready-processed emulsion asphalt was examined suitable for protective coating in metal emulsion asphalt and protective coating in roofing as per ASTM specification. The mixture of pertamina asphalt and buton asphalt may 'increase the quality of emulsion asphalt.

Abstrak :
Telah dilakukan sintesis dan karakterisasi polimerisasi oksidasi kimia dari monomer pirol menggunakan oksidan amonium persulfat (APS) dalam media pelarut air, melalui teknik polimerisasi emulsi metode batch selama 4 jam dengan kecepatan agitasi 900 rpm dalam temperatur ruang. Surfaktan yang digunakan diantaranya, surfaktan anionik: Sodium dedocyl sulfate (SDS) dan surfaktan nonionik: Nonylphenol Ethoxylate (NP.EO) dengan 10 mol EO. Senyawa PPy dalam penelitian ini berbentuk padatan (serbuk) berwarna hitam. Terbentuknya PPy dapat diindentifikasi berdasarkan hasil spektra FTIR terlihat munculnya serapan puncak polimer konduktif PPy dengan intensitas yang kuat pada bilangan gelombang 3001 cm-1, 1503 cm-1, 1428 cm-1, 1175 cm-1 dan 1087 cm-1. Berdasarkan profil perubahan temperatur dan perubahan warna selama proses polimerisasi terlihat polimerisasi emulsi relatif lebih lama kecepatan reaksinya dibandingkan dengan polimerisasi sedimentasi. Nilai pH sistem reaksi polimerisasi dengan surfaktan lebih tinggi (penambahan larutan SDS pH sistem 3.3) dibandingkan polimerisasi tanpa surfakan (1.8). Nilai konduktifitas (σ) PPy dengan surfaktan lebih tinggi (mencapai 186 kali) dibandingkan tanpa surfaktan. Polimerisasi emulsi menggunakan surfaktan anionik, SDS sangat efektif meningkatkan nilai konduktivitas PPy. ...... A conductive Polypyrrole (PPy) has been successfully synthesized and characterized. The PPy was prepared through oxidative chemical polymerization using ammonium persulfate (APS) as an oxidizing agent in aqueous media. Anionic and non-ionic emulsifiers, sodium dodecyl sulfate (SDS), nonylphenol (NP) ethoxylate (EO) with 10 mole EO were respectively used during polymerization to increase the electrical conductivity. In this research is produced PPy which is formed as black powder. The FTIR spectrum of PPy indicates a change in the absorbance peaks of pyrrole monomer, emergence of strong absorbtion peaks specially at 3001 cm-1, 1503 cm-1, 1428 cm-1, 1175 cm-1 and 1087 cm-1 which is indicating the conductive polymer polypyrrole is formed. Based on color changing and temperature changing during the polimerization process, the reaction rate of emulsion polymerization is shown relatively slower than sedimentation polymerization. The pH value of SDS added solution was 3.3 higher than that of SDS free solution (1.8). The final characteristic of PPy was carry out by measuring the electrical conductivity (σ) value. It is concluded that the presence of surfactant in a polymerization reaction increased the electrical conductivity of PPy (reached 186 times higher) compared with that obtained of emulsifier free solution. Anionic surfactant, SDS is more effective to enhance the electrical conductivity value of PPy.

Abstrak :
Ukuran partikel merupakan salah satu faktor yang menentukan sifat polimer emulsi. Untuk aplikasi coating, dibutuhkan polimer emulsi dengan ukuran partikel yang kecil agar diperoleh hasil coating yang halus, kekuatan adhesi dan ketahanan terhadap air yang baik, serta kestabilan yang cukup lama. Penelitian ini bertujuan melihat pengaruh dari surfaktan natrium dodesil benzena sulfonat (SDBS) rantai bercabang serta beberapa teknik polimerisasi emulsi terhadap ukuran partikel kopoli(stirena/butil akrilat/metil metakrilat) dengan menggunakan kombinasi surfaktan anionik dan nonionik (nonil fenol, EO|U) serta inisiator ammonium persulfat. Hasil pengukuran DSC, solid content, dan IR menunjukkan bahwa terbentuk kopoli (stirena/butil akrilat/metil metakrilat). Dari hasil yang diperoleh, dapat dilihat bahwa terbentuk grit yang banyak. Teknik batch dapat menghasilkan solid content tertinggi yaitu 38,47%. Teknik semi kontinyu secara umum menghasilkan viskositas yang tinggi yaitu 128 mPas. Surfaktan SDBS rantai bercabang secara umum menghasilkan polimer emulsi dengan ukuran partikel yang kecil tetapi grit yang terbentuk lebih banyak. Banyaknya persen seeding monomer dan inisiator yang ditambahkan ke dalam initial charge mempengaruhi ukuran partikel polimer emulsi yang terbenluk, dan jumlah inti yang dihasilkan.

Abstrak :
ABSTRACT
Curcumin is an active ingredient obtained from the turmeric plant and has been reported to have many biological activities as anti cancer, an anti-inflammatory, antimicrobial and antioxidant although its clinical use is limited because of its poor solubility in water and inadequate dissolution. Objective- The aim of this research is to prepare dry dispersible emulsion (DDE) of curcumin and to know its effect on enhancing the dissolution rate of curcumin. Method-The dry dispersible emulsion was prepared byusing a high-speed homogenization and ultrasonic technique. Caseinate sodium was used as the surfactant while virgin coconut oil was used as the lipid. Dispersion of the dry emulsion was then spray dried. Dry dispersible emulsion powder was characterized and compared with standard curcumin. Result-The DSC test showed a significant decrease in the melting point. Conclusion-The dissolution rate of curcumin can be significantly improved with a dry dispersible emulsion formulation. In formula A and formula C, the maximum dissolved curcumin increased by 83.65%, 81.53% in formula B, and 79.12% in formula C

Abstrak :
Graft copolymerization of an acrylonitrile monomer onto Deproteinized Natural Rubber (DPNR) is an important process in the modification of Natural Rubber (NR) to increase its oil resistance. However, coagulation at the beginning of the process was a problem causing a copolymerization foil to occur. The presence of a styrene monomer is therefore expected to improve the emulsion condition so that coagulation can be prevented in the early reaction step. For comparison purposes, the processes with and without styrene were investigated. The influence of the concentration of styrene as well as the ratio of the DPNR:monomer on the stabilization process were also observed. The results showed that the addition of styrene could improve the stabilization process as proven by Fourier Transform Infrared Spectroscopy (FTIR). The presence of the functional group of CºN at FTIR proved the production of the polyacrylonitrile in the mixture. The investigation showed that the concentration of styrene monomer, which led to the emulsion stability, is up to 1.5 wt% concentration of styrene at the ratio of DPNR:monomer (M) of 70:30 wt%.

Abstrak :
The use of water-in-diesel (W/D) emulsion fuel has the potential to promote better performance with lower emissions in existing diesel engines. The present study aims to analyzes the influence of operating parameters on the overall engine performance and emission characteristics using W/D emulsion fuel and to obtain the optimum level for favorable performance and emission levels. The engine operating parameters were optimized using a Taguchi–grey relation based multi-response optimization tool. Two controlling parameters, namely compression ratio (CR) and percentage of W/D, were considered as input process parameters. An L16 orthogonal array was used to collect the output responses (performance and emissions) under varying engine load conditions. The signal-to-noise (S/N) ratio and grey relational analysis were used to analyze the performance and emission parameters. From the results obtained, it is noted that both controlling parameters have a significant effect on the performance and emission levels. The optimum level of performance and emission levels are obtained at a CR of 18 and water concentration of 10%. Moreover, under these optimum conditions, i.e. at 10% of water concentration, the fuel properties are at par with the standard diesel fuel properties requirement.