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Abstrak :
Film selulosa bakteri telah berhasil dibuat dari air kelapa sebagai sumber mikronutrien menggunakan biakan Acetobacter xylinum. Film selulosa bakteri selanjutnya diiradiasi dengan mesin berkas elektron pada rentang dosis 15-120 kGy, laju dosis 15 kGy/ pass dan temperatur ruang. Setelah diiradiasi, selulosa bakteri tersebut dikopolimerisasi cangkok dengan monomer akrilonitril. Kondisi optimum untuk kopolimerisasi cangkok akrilonitril pada selulosa bakteri adalah pada dosis 75 kGy, temperatur 600C, waktu 3 jam, dan konsentrasi akrilonitril 30% b/b. Derajat pencangkokan tertinggi yang diperoleh adalah sebesar 56,03 %. Selulosa bakteri tercangkok akrilonitril (SB tercangkok PAN) selanjutnya diamidoksimasi. Amidoksimasi dilakukan dengan penambahan hidroksilamin hidroklorida 6 % b/v dalam pelarut metanol : air = 50 : 50 v/v pada pH 7, dan diperoleh waktu optimum selama 2 jam dengan densitas gugus amidoksim yang diperoleh sebesar 5,425 mmol/ gram. Karakterisasi gugus fungsi film selulosa bakteri sebelum dan sesudah kopolimerisasi cangkok dengan akrilonitril, serta setelah diamidoksimasi dilakukan dengan menggunakan Fourier Transform Infra Red (FTIR), analisis mikrostruktur dengan Scanning Electron Microscopy (SEM), analisa derajat kristalinitas menggunakan X-ray diffraction (XRD), serta uji ketahanan terhadap panas diukur dengan Thermal Gravimetry Analysis (TGA) dan Differential Scanning Calorimetry (DSC). Hasil karakterisasinya mengindikasikan bahwa SB tercangkok PAN dan selulosa bakteri teramidoksimasi (SB-Am) telah berhasil disintesis pada penelitian ini. Film tersebut selanjutnya diuji kemampuan adsorpsinya terhadap ion logam Cu2+ dan Pb2+. Nilai koefisien distribusi selulosa bakteri, SB tercangkok PAN, dan SB-Am pada pH 6 terhadap ion logam Cu2+ masing-masing sebesar 0,26, 0,23, dan 0,37 L/gram adsorben, sedangkan terhadap ion logam Pb2+ masing-masing sebesar 0,41, 0,405, dan 0,52 L/gram adsorben.

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Bacterial cellulose films have been successfully synthesized from coconut water as a source of micronutrients using Acetobacter xylinum. Bacterial cellulose film irradiated using electron beam machine at a dose range of 15-120 kGy and dose rate 15 kGy/ pass in room temperature. After irradiated, the bacterial cellulose grafted with acrylonitrile monomer. The optimum conditions for graft copolymerization condition were at the dose of 75 kGy, temperature 600C ,3 hours time of reaction, and the concentration of acrylonitrile was 30 % w/w. The highest degree of grafting obtained was 56,03 % . Amidoximation then performed by the addition of hydroxylamine 6 % w/v in methanol : water = 50 : 50 v/v solvent under pH 7 and obtained the optimum time for amidoximation reaction was 2 hours. Amidoxime density obtained was 5.425 mmol/ gram. Characterization of functional groups in bacterial cellulose films before and after graft copolymerization with acrylonitrile, as well after amidoximation performed by Fourier Transform Infrared (FTIR), microstructure was analyzed by Scanning Electron Microscopy (SEM), analysis of the degree of crystallinity using X-ray diffraction (XRD), thermal resistance properties was measured by Thermal Gravimetry Analysis (TGA) and Differential Scanning Calorimetry (DSC) .The results show that bacterial cellulose-g-polyacrylonitrile (BC-g-PAN) and amidoximated bacterial cellulose films (Am-BC) have been synthesized successfully. Subsequently, Cu2+ and Pb2+ metal ion adsorption studies were conducted using those films. Coeficient distribution of bacterial cellulose, BC-g-PAN, and Am-BC under pH 6 toward Cu2+ions respectively were 0,26, 0,23, dan 0,37 L/gram of adsorbent, while toward Pb2+ions, respectively were 0,41, 0,405, and 0,52 L/gram of adsorben.

Abstrak :
Modifikasi selulosa dengan asam akrilat menggunakan pengikat silang Trimethallyl Isocianurate (TMAIC) dengan teknik kopolimerisasi cangkok pra-iradiasi telah berhasil dilakukan. Penelitian ini bertujuan untuk menghasilkan suatu material bersifat adsorben. Pengikat silang TMAIC digunakan untuk meningkatkan ketahanan kimia dan termal dari selulosa-g-AA. Kondisi optimum reaksi pencangkokan diperoleh pada dosis radiasi 60 kGy, konsentrasi TMAIC 0,5 % (w/v), konsentrasi monomer 10 % (v/v), suhu pencangkokan 90°C dan waktu pencangkokan 6 jam, dengan persen pencangkokan rata-rata sebesar 65,27 % dan pengembangan dalam air sebesar 922,26%. Hasil sintesis kopolimer selulosa-TMAIC-g-AA telah berhasil dikarakterisasi dengan FTIR, TGA dan SEM. Selulosa terikat silang dapat digunakan sebagai adsorben ion logam Pb2+, dengan kapasitas adsorpsi sebesar 2,5954 mg/g pada waktu kontak 2 jam dan pH 5 (konsentrasi awal Pb2+ 10 mg/L). Isoterm adsorpsi yang sesuai dengan adsorpsi Pb(II) dengan kopolimer adalah isoterm adsorpsi Langmuir dengan linearitas 0,9868. ......Modification of cellulose with acrylic acid monomers using Trimethallyl Isocianurate ( TMAIC ) as crosslinker by mean of preirradiation graft copolymerization technique have been successfully carried out. This research aims to produce a material which has adsorbent properties. TMAIC as crosslinking agent can be used to improve the chemical and thermal resistance of cellulose-g-AA. The optimum condition for graft copolymerization is obtained at 60 kGy radiation dose, 0,5 % (w/v) TMAIC, 10 % (v/v) monomer, 90°C grafting temperature and 6 hours reaction time, with 65,27 % grafting average and 922,26 % swelling in water. Synthesized copolymers cellulose-TMAIC-g-AA was successfully characterized by FTIR, TGA and SEM. Crosslinked cellulose-TMAIC-g-AA can be used as Pb2+ metal adsorbent, having adsorption capacity of 2,5954 mg/g at 2 hours contact time and pH 5 (initial concentration of Pb2+ 10 mg/L). Adsorption isotherms in accordance with the adsorption of Pb ( II ) by copolymer is Langmuir adsorption isotherm with linearity 0.9868.

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 :
Pada penelitian ini dilakukan sintesis kopolimer pH-sensitif poli(N-vinil pirolidon)-blok-poli(N-hidroksimetil akrilamida) menggunakan metode atom transfer radical polymerization (ATRP) dengan memvariasikan komposisi monomer N-hidroksimetil akrilamida untuk melihat pengaruhnya terhadap sensitivitas kopolimer blok tersebut pada berbagai pH. Untuk melihat gugus fungsi yang terdapat pada kopolimer digunakan FT-IR, sedangkan struktur kopolimer dikarakterisasi menggunakan 1H-NMR. Kemudian, karakterisasi menggunakan particle size analyzer dilakukan untuk melihat sensitivitas dari kopolimer dengan melihat perubahan ukuran partikel kopolimer pada berbagai pH. Dalam penelitian ini, kopolimer poli(N-vinil pirolidon)-blok-poli(N-hidroksimetil akrilamida) mengalami perubahan ukuran partikel pada berbagai pH. Pada pH asam ukuran partikel kopolimer akan lebih besar dibandingkan pada pH basa. Selain itu, semakin banyak komposisi monomer N-hidroksimetil akrilamida maka ukuran partikel akan lebih besar. ...... In this reseach, the synthesis of pH-sensitive poly(N-vinyl pyrrolidone)-block-poly(N-hydroxymethyl acrylamide) was carried out using atom transfer radical polymerization (ATRP) by varying the monomer composition of N-hydroxymethyl acrylamide to observe the effect of monomer composition on copolymer sensitivity at various pH. Functional groups in copolymers were characterized using FT-IR, and the structures of copolymers were investigated with ¹H-NMR. In order to observe copolymer sensitivity to pH, characterization using particle size analyzer was performed by studying the changes in particle sizes of copolymers at various pH. In this research, particle sizes of poly(N-vinyl pyrrolidone)-block-poly(N-hydroxymethyl acrylamide) changes in various pH. At low pH, the particle sizes of copolymers became much bigger than at high pH. Besides that, particle sizes increased along with the increasing monomer composition of N-hydroxymethyl acrylamide.