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Abstrak :
ABSTRAK
Telah dilakukan sintesis polianilin melalui polimerisasi oksidatif dengan menggunakan oksidator ammonium persulfate APS dengan metode kontinyu. Proses polimerisasi dilakukan dalam media asam kuat, HCl 1,5 M dibandingkan dengan media netral dengan variasi suhu lingkungan 20 oC, 30 oC dan 50 oC. Temperatur proses polimerisasi, pH larutan dan ukuran partikel dari polimer yang terbentuk setiap 5 menit hingga 60 menit pertama, dalam kurun waktu 8 jam. Nilai pH hasil pengukuran menunjukkan bahwa selama pembentukan PANI tidak banyak berubah, suhu larutan selama proses relatif sama. Pertumbuhan ukuran partikel selama proses polimerisasi dalam menunjukkan adanya tahapan inisiasi, propagasi dan terminasi baik dalam media netral dan asam kuat. Dalam media netral, pertumbuhan ukuran partikel berjalan relatif lambat, dan didominasi oleh pembentukan oligomer anilin oligoanilin yang berantai pendek. Ukuran partikel rata-rata sebesar 29 ndash; 39 m diperoleh dari polimerisasi dalam kedua media. Kedua media juga menunjukkan semakin rendah temperature media semakin besar ukuran partikel yang dihasilkan. Efek doping dengan p-TSA terhadap PANI-EB dilakukan sebagai konfirmasi untuk menunjukkan penerapan dari polianilin terdoping. Diketahui bahwa semakin tinggi suhu maka konduktivitas semakin naik. Hal ini sebagai bukti polianilin terdoping bersifat sebagai semikonduktor. Semakin besar ukuran partikel dan semakin tinggi konsentrasi doping akan meningkatkan konduktivitas dan menurunkan energi gap dari PANI terdoping p-TSA yang berakibat pada penurunan serapan terhadap gelombang mikro.

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ABSTRACT
The synthesis of polyaniline was carried out by the oxidative polymerization method using ammonium persulfate APS by continuous method, in strong acid medium 1.5 M HCl and neutral medium with ambient temperature variation at 20 C, 30 C and 50 C. Measuring of the process temperature, the pH of the process solution and the particle size formation every 5 minutes to the first 60 minutes, and every hour until process has finished for 8 hours. The pH value of the measurements shows that during the formation of PANI does not change much, the temperature of the solution during the process is relatively the same. The growth of particle size during the polymerization process in indicating the presence of initiation, propagation and termination stages both in neutral and strong acid medium. In neutral media, growth of particle size formation runs relatively slowly, and it was dominated by the formation of short chain aniline oligomers oligoanilines . The average particle size of 29 39 m was obtained from polymerization in both media. Both media also show the lower the media temperature the larger the particle size have formed. The doping effect with p TSA on PANI EB was performed as a confirmation to demonstrate the application of a doped polyaniline. It is known that the higher the temperature the conductivity increases. This is a proof of polyaniline doped has behavior as semiconductor. The larger the particle size and the higher the doping concentration will increase the conductivity and decrease the gap energy of the p TSA doped PANI that decreased of microwave absorbing properties.

Abstrak :
ABSTRAK
Polianilin telah disintesis melalui polimerisasi oksidatif kimia dengan Ammonium Peroksidisulfat APS sebagai inisiator dalam berbagai konsentrasi 50 g/L, 100 g/L dan 200 g/L . Polimerisasi anilin berjalan dengan ditandai adanya kenaikan temperatur karena reaksi yang terjadi dalam larutan mencapai temperatur tertinggi sebesar 42 C pada larutan dengan konsentrasi APS 200 g/l. Hasil dari reaksi polimerisasi oksidatif berupa basa emeraldin PANi-EB . Struktur PANi dikonfirmasi dengan FTIR ditandai dengan adanya vibrasi stretching pada cincin benzenoid dan quinoid pada bilangan gelombang 1400-1500 cm-1. Sifat konduktif PANi diperoleh melalui pemberian protonasi menggunakan asam kuat yaitu HCl dan HClO4. Nilai konduktivitas PANi-EB mengalami peningkatan 102 kali setelah doping menggunakan HCl dan 106 kali pasca doping HClO4. Semua PANi hasil sintesis memiliki kemampuan penyerapan gelombang elektromagnetik pada rentang frekuensi 10 GHz-15 GHz. Semakin tinggi nilai resistivitas PANi yaitu makin rendah nilai konduktivitas, semakin tinggi juga nilai reflection loss RL . Nilai RL tertinggi sekitar -18 dB pada frekuensi 12,5 GHz dan 14,3 GHz diperoleh dari PANi-EB hasil polimerasi dengan konsentrasi APS sebesar 200 g/l.

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ABSTRAK
Polianiline has been synthesized by chemical oxidative polymerization using Ammonium Polyaniline has been synthesized through chemical oxidative polymerization with Ammonium Peroxidisulfate APS as an initiator in various concentrations 50 g l, 100 g l and 200 g l . The polymerization reactions of aniline are characterized by an increase in temperature due to the reaction occurring in the solution, reaching the highest temperature of 42 C in a solution with APS concentration of 200 g l. Result of oxidative polymerization reaction is the emeraldine base polyaniline or PANi EB. The PANi formation was confirmed by FTIR which characterized by stretching vibrations in benzenoid and quinoid rings at wave numbers 1400 1500 cm 1 respectively. The conductive property of PANi was obtained through doping by a protonation using strong acids HCl and HClO4. It was found that conductivity value PANi EB increased 102 times after doping with HCl and 106 times after doping with HClO4. Moreover, all synthesized PANi has the ability to absorb electromagnetic waves in the frequency range 10 GHz 15 GHz. The higher the resistivity value of PANi that is the lower the conductivity value, the higher the reflection loss RL . The highest RL values of about 18 dB at 12.5 GHz and 14.3 GHz frequencies were obtained from PANi EB polymeration results with APS concentrations of 200 g l.

Abstrak :
Polyanilin (PANi) adalah salah satu jenis polimer konduktif yang masih mendapat perhatian besar dan menjadi subjek investigasi intensif sampai saat ini. Dalam studi ini, PANi disintesis melalui metode reaksi polimerisasi oksidatif kimia. Sampel untuk penyelidikan dipersiapkan melalui penggunaan surfaktan dengan tiga variasi yaitu, larutan reaksi tanpa menggunakan surfaktan, dengan menggunakan surfaktan sodium octylsulfate atau SOS (NaC8H17SO4) dan sodium dodecylsulfate atau SDS (NaC12H25SO4) masing-masing dengan konsentrasi 1%. Selama proses polimerisasi, data pH, viskositas, densitas, dan suhu larutan diukur secara berkala. Hasil dari reaksi adalah serbuk PANi basa emeraldin atau PANi-EB yang kemudian didoping dengan HClO4 untuk memperoleh sifat konduktivitas listrik. Semua PANi yang disintesis dievaluasi oleh FTIR, TGA, DSC, PSA dan FPP. Hasil penelitian ini menyimpulkan bahwa perpanjangan rantai karbon surfaktan tidak berkontribusi banyak terhadap peningkatan nilai konduktivitas listrik. Perpanjangan rantai karbon surfaktan hanya memengaruhi distribusi ukuran partikel. PANi konduktif dengan penambahan 1% SDS memiliki distribusi ukuran partikel dengan ukuran partikel rata-rata ~ 191 nm dan PANi konduktifif dengan penambahan 1% SOS memiliki ukuran partikel rata-rata 291 nm. Kedua nilai ini jauh lebih halus dibandingkan dengan nilai ukuran rata-rata partikel PANi bebas surfaktan (~ 723 nm). Konduktivitas listrik PANi / SOS 1% dan PANi / SDS 1% setelah didoping dengan HClO4 masing-masing adalah 1,16 S/cm dan 1,12 S/cm. ......Polyaniline (PANi) is one type of conductive polymers which still receive large attentions and being a subject of intensive investigation up to date. In this study, PANi was synthesized by a chemical oxidative polymerization reaction method. Samples for under investigation were prepared through three fixed variations during polymerization reactions respectively, using no surfactants, with surfactants of sodium octylsulfate SOS (NaC8H17SO4) and sodium dodecylsulfate SDS (NaC12H25SO4) of 1% concentration. During the polymerization process data of pH, viscosity, density and temperature of solutions were collected periodically. The result of the reaction is an emeraldine base PANi or PANi-EB, which was then doped with HClO4 for obtaining the electrical conductivity property. All synthesized PANi were evaluated by FTIR, TGA, DSC, PSA and FPP. The research work of current study concluded that the extension of carbon chain of the surfactant did not contribute much the increase in conductivity values. The extension of the surfactant carbon chain only affected the particle size distribution. Conductictive PANi with the addition of 1% SDS has a particle size distribution with a mean particle size ~ 191 nm and that of 1 % SOS has a mean particle size ~ 291 nm, which are much finer than that of 291 nm of PANi free of surfactant (~ 723 nm). The electrical conductivity of PANi / SOS 1% and PANi / SDS 1% after doped with HClO4 were respectively 1.16 S/cm and 1.12 S/cm.