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Abstrak :
Tesis ini meneliti mengenai pengaruh asam stearat terhadap basal spasi organoclay dan sifat-sifat dari nanokomposit karet alam/organoclay terekspansi serta pengaruh organoclay terekspansi terhadap sifat dan morfologi dari nanokompositnya. Nanokomposit karet alam/organoclay terekspansi dibuat dengan cara pelelehan kompon. Hasil penelitian menunjukkan bahwa peningkatan dosis asam stearat dapat meningkatkan basal spasi organoclay sehingga organoclay terekspansi dapat terdispersi dengan merata di dalam matriks karet alam, menghasilkan nanokomposit dengan sifat mekanik dan swelling yang meningkat. ......This thesis are to studies the effect of stearic acid on organoclay d-spacing and properties of natural rubber/expanded organoclay and the effect of expanded organoclays on properties and morphology of its nanocomposites. Natural rubber/expanded organoclay nanocomposites was prepared by using melt compounding technique. The result showed that the increasing of stearic acid doses could increase the d-spacing of organoclay so that expanded organoclay can disperse uniformly in natural rubber matrix, produces nanocomposites with increasing of mechanical and swelling properties.

Abstrak :
Data XRD dari nanokomposit Ti-Si-N telah dianalisis menggunakan program GSAS berbasis metode Rietveld untuk mengidentifikasa fasa-fasa pembentuk serta komposisinya dan mencari pengaruhnya terhadap kekerasan material tersebut. Telah ditemukan fasa-fasa baru dalam sampel tersebut, disamping fasa-fasa nanokomposit nc-TiN/a-Si3N4 & a-/nc-TiSi2 yang telah banyak dikenal. Dari fasa-fasa kristal yang diperoleh, setelah dilakukan perhitungan fraksi fasa amorf Si3N4 dan TiSi2 maka diperoleh bahwa kekerasan optimal terjadi pada kandungan a-Si3N4 8 wt.%.

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Phase composition analysis using rietveld methode and it?s influence to the hardness of Ti-Si-N nanocomposites. XRD data of nanocomposites Ti-Si-N have been analysed using GSAS based on Rietveld Method in order to identify phases and their composition as well as its influence on the hardness of these nanocomposites. Several new phases have been found in the sample beside the nc-TiN/a-Si3N4& a-/nc-TiSi2 that have been known widely. From the obtained crystalline phase, after the calculation of amorf Si3N4 and TiSi2 phase fraction, it is found that the optimum hardness can be reached when the fraction of a-Si3N4 phase around 8 wt.%.

Abstrak :
Epoxy-organo clay nanocomposite materials are constructed from a polymer as a matrix and an organoclay as filler. Epoxy-organo clay nanocomposites have been synthesized using various curing agents. The aim of this research was to study the influence of the curing agent and the organoclay contents to the structure and mechanical properties of nanocomposites materials. Epoxy-organo clay nanocomposites were synthesized using cycloaliphatic amine as a curing agent and a montmorillonite organoclay (MMT) as filler through an in situ polymerization method. XRD and TEM technique provide more detail information to understand the structure that relates to the mechanical properties of the materials. Tensile test, compressive test and hardness test were conducted based on ASTM and JIS standards. The fracture surfaces after tensile tests were analyzed using SEM. The nanocomposite properties were compared to glass-fiber composites which were synthesized using wet-laminating method. It was found that the curing agent is influence to the nanocomposites structure which was shown by the change of d-spacing before and after the addition of the agent curing. XRD and TEM techniques showed that both intercalated and exfoliated structure have been formed. TEM image also exhibited that the number of intercalated structure was higher when the organoclay content was higher. It can be said that TEM techniques provides a better understanding of the nanocomposites structure and the number intercalated structure increase as the organoclay increases. The organoclay contain also influences to mechanical properties of nanocomposite materials. The addition of 10.5 wt.% organoclay improved the tensile modulus by 185% but and decreased tensile strength by 186% and 49%, and these values are lower of 36% and 90% compared to glass fiber composites. These decreases in the strength may be attributed to the fact that agglomerate and void was formed. From compression test, the addition of 3.1 wt.% organoclay demonstrated a 102% increase in compression strength and a 93% increase in load maximum compare to epoxy resin. But, that compression strength value lower of 11% compared to glass fiber composites. For the maximum load, the addition of 3.1 wt.% organoclay improved 246% compared to glass fiber composites. Addition of 7.3 wt.% organoclay demonstrated an increase of modulus of the epoxy resin by 93% and 2% compare to glass fiber composites. Meanwhile, the addition of 10.5% organoclay cause decreasing in yield compression up to 31%, but this higher value equal to 406% from is glass fiber composites. While that, result of hardness test do not show the make-up of value meaning in comparison with epoxy matrix.

Abstrak :
Nanokomposit polimer merupakan bahan yang terdiri dari paduan polimer dan partikel-partikel pendispersi dengan ukuran nanometer, misalnya partikel clay. Nanokomposit memiliki kelebihan dibandingkan dengan komposit konvesional diantaranya, modulus , kekuatan, dan hambatan panasnya lebih tinggi . Agar clay terdispersi di dalam polimer, maka reaksi pertukaran ion harus dilakukan pada clay agar permukaan clay kompatibel dengan polimer sehingga memudahkan bagi molekul polimer masuk di antara lapisan clay tersebut. Metode pembuatan nanokomposit berbasis polypropylene (PP) dalam penelitian ini adalah pencampuran langsung polypropylene ( PP ) dengan Organo Layered Silicate (OLS) dan Polipropylene grafted Maleic Anhydride ( PP-g-MA ) dengan menggunakan twin screw extruder. Hasil XRD dan TEM, dari nanokomposit polypropylene - clay menunjukkan bahwa bahan mempunyai struktur eksfoliasi dan interkalasi. Struktur eksfoliasi diperoleh pada sampel PP - OLS I.44 PT yang mengalami satu kali ekstrusi pada 100 rpm. Sampel ini menunjukkan kenaikan kuat tarik dan HDT masing-masing sebesar 7,36% dan 30,06% terhadap PP murni. Sampel dengan dua kali ekstrusi memiliki kenaikan modulus elastisitas sebesar 41.19% dan HDT sebesar 29,38%. ......Polimer nanocomposites are materials that are formed by polimer and dispersed particles in nanometer size, such as clay particles. Polimer nanocomposites have better properties, such as modulus, strength, and heat recistance, compared to the conventional composites. In order to make the clay particles disperse within the polimer, a cation exchange reaction must be done on the clay surface so that the polimer moleculer one able to get into space between the layers. In tha research, polypropylene based nanocomposites were prepared by a direct mixing with polypropylene (PP) with organo layered silicate (OLS) and polypropylene grafted Maleic Anhydride (PP-g-MA) using a twin-screw extruder. The XRD and TEM analysis from this PP-clay nanocomposites showed that an exfoliated and an intercalted structures were formed. Exfolition structure was found on the PP-OLS I.44 PT samples which wereprepared by one time extrusion on a 100 rpm. These sample show on increasis on tensile strength and HDT of 7,36% and 30,06% respectively compared to pristine PP.Two times extrution on the samples result on the increasing of elastic modulus by 41,19% and HDT by 29,38%.

Abstrak :
Nanokomposit polimer-clay merupakan bahan dengan matrik polimer yang diperkuat dengan nanofiller seperti lapisan silika. Pada penelitian ini pembuatan nanokomposit diawali dengan pembuatan masterbatch organo clay dengan penggunaan pelarut kemudian dicampur dengan polimer. Masterbatch dalam penelitian ini dihasilkan dari pencampuran Organo Layered Silicate (OLS), Ethylene Glycol, dan Polypropylene grafted maleic An hydride (PP-g-MA). Pembuatan nanokomposit polipropilen clay dilakukan di dalam mesin Rheomex (twin screw extruder) dengan mencampur masterbatch dan PP. Pengujian material yang dilakukan adalah pengujian XRD, TEM, HDT, dan uji tarik. Hasil yang diperoleh pada pengukuran HDT menunjukkan kenaikan sebesar 22 % pada komposit OLS Nanomer I.44PT dibanding dengan nilai HDT PP murni. Modulus elastisitas menunjukkan kenaikan sebesar 36 % pada komposit OLS DTDA dibanding dengan PP murni. ......Polimer - clay nanocomposite is a material with a polimer matrix which is toughened by nanofiller such as silica particles. In this research,, nanocomposite was prepared from the production of organoclay masterbatch through a mixture of a solvent and a polymer. The masterbatch were produced from a mixture of organo layered silicate (OLS), Ethylene Glycol, and Polypropylene grafted maleic An hydride (PP-g-MA). The production of PP clay nanocomposite was done in Rheomex machine (twin screw extruder) by mixing the masterbatch and PP. The materials evaluated were using XRD, TEM, HDT, and tensile test. The results of HDT measurement showed that the OLS Nanomer composites were 22 % higher compared to the pristine PP. The modulus of elasticity of OLS ? DTDA composites increased 36 % compared to the pristine PP.

Abstrak :
ABSTRAK
Senyawa derivat piran telah berhasil disintesis dengan mereaksikan kurkumin, benzaldehida, dan asam barbiturat senyawa 3 melalui reaksi kondensasi Knoevenagel dan adisi Michael. Namun, 2 reaksi lainnya tidak berhasil membentuk senyawa derivat piran, yaitu senyawa 1 dan senyawa 2. Pada kedua reaksi tersebut digunakan reaktan dimedon, benzaldehida/sinamaldehida, dan malononitril. Ketiga produk yang terbentuk tersebut dianalisis menggunakan instrumentasi FTIR, UV-Vis, dan GC-MS atau LC-MS. Pada reaksi tersebut digunakan nanokatalis Fe3O4@kitosan yang berhasil disintesis dengan metode in situ dan dikonfirmasi dengan instrumentasi FTIR, XRD, TEM, dan PSA. Berdasarkan hasil optimasi reaksi diperoleh kondisi optimum untuk senyawa 1 adalah 1 jam reaksi, suhu ruang, dan 2,5% wt katalis dengan mol sebesar 85,24%, untuk senyawa 2 pada 45 menit reaksi, suhu ruang, dan 5% wt katalis dengan mol sebesar 48,44%, serta 8 jam reaksi, refluks, dan 5% wt untuk senyawa 3 dengan kemurnian sebesar 52,99%. Senyawa-senyawa hasil sintesis memiliki bioaktivitas sebagai antioksidan dengan nilai IC50 sebesar 57, 21, 23, 61, dan 7,47 ppm.

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ABSTRACT
Pyran derivatives were successfully synthesized by reacting curcumin, benzaldehyde, and barbituric acid compound 3 through Knoevenagel condensation and Michael addition reactions. Nevertheless, it was found that other 2 processes did not form pyran derivative compounds. Both of them used dimedone, benzaldehyde cinnamaldehyde, and malononitrile as reactants. Characterization of the three of products were performed by using FTIR, UV Vis, and GC MS or LC MS instrumentation. Beside that, Fe3O4 chitosan nanocatalyst also used in the reactions, which was synthesized by in situ method and characterized by FTIR, XRD, TEM, and PSA instrumentation. The optimum conditions for producing compound 1 were 1 hour at reaction, room temperature, and 2,5% wt of catalyst with mol of 85,24%, compound 2 was at 45 min of reaction, room temperature, and 5% wt of catalyst with mol of 48,44%, and 8 hours of reaction, reflux, and 5% wt for compound 3 with purity of 52,99%. Bioactivity as antioxidant was discovered in the syhthesized compounds with the IC50 values of 57, 21, 23, 61, and 7,47 ppm for the compound of 1, 2, and 3, respectively.

Abstrak :
ABSTRAK
Natrium alginat yang berasal dari ganggang coklat Sargassum sp. telah berhasil diisolasi pada variasi suhu, yaitu 30°C, 45°C dan 60°C. Rendemen tertinggi didapatkan pada suhu 30°C, dengan nilai sebesar 62.9%. Hasil isolasi menunjukkan massa natrium alginat dipengaruhi oleh suhu. Natrium alginat hasil isolasi dikarakterisasi dengan FTIR, XRD dan SEM-EDX. Natrium alginat digunakan untuk membentuk nanokomposit kalsium alginat-TiO2/SiO2 dengan metode enkapsulasi TiO2/SiO2. Proses enkapsulasi dilakukan dengan konsentrasi larutan natrium alginat rendah dan penambahan ion Ca2+ dari CaCl2.2H2O, sehingga terbentuk gel halus kalsium alginat. TiO2/SiO2 dibentuk dari proses sol-gel prekursor tetraetil ortosilikat (TEOS) dan titanium isopropoksida (TTIP) dalam keadaan asam. Nanokomposit kalsium alginat-TiO2/SiO2 dikarakterisasi dengan FTIR, XRD, SEM-EDX dan TEM. Hasil pengukuran SEM menunjukkan bentuk partikel TiO2/SiO2 dengan permukaan berserat yang mengkonfirmasi keberhasilan pembentukan nanokomposit kalsium alginat-TiO2/SiO2. Nanokomposit kalsium alginat-TiO2/SiO2 yang bersifat asam dan berserat dimanfaatkan sebagai katalis dalam proses konversi glukosa menjadi 5-hidroksimetilfurfural dengan pelarut dimetilsulfoksida (DMSO). Rendemen 5-hidroksimetilfurfural didapatkan pada suhu 140°C dan waktu 4 jam, sebesar 12.832%. Kinetika reaksi glukosa menjadi 5-hidroksimetilfurfural mengikuti persamaan laju reaksi orde satu dengan energi aktivasi sebesar 253.949 kJ/mol.

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ABSTRACT
The sodium alginate from Sargassum sp. brown seaweed was isolated at varied temperatures which are 30°C, 45°C dan 60°C. The highest yield is obtained at 30°C which the value is 62.9%. The yield obtained showed that a sodium alginate's mass affected by a temperature. The isolated sodium alginate was characterized by FTIR spectra, XRD spectra and SEM-EDX imaging. The sodium alginate was used to form calcium alginate-TiO2/SiO2 nanocomposite with an encapsulation method of calcium alginate-TiO2/SiO2. The encapsulation process was done with the low concentration of alginate solution and Ca2+ ion from CaCl2.2H2O, thereby calcium alginate pragel was formed. The TiO2/SiO2 was synthesizing by sol-gel process of tetraethyl orthosilicate (TEOS) and titanium isopropoxide precursors (TTIP) in acid condition. The calcium alginate-TiO2/SiO2 nanocomposite was characterized by FTIR spectra, XRD spectra, SEM-EDX imagings and TEM imagings. The SEM images showed the morphology of TiO2/SiO2 particle with a fibrous surface which confirmed that the calcium alginate-TiO2/SiO2 nanocomposite was synthesized. The calcium alginate-TiO2/SiO2 nanocomposite which has acidity and fibrous properties was utilized as a catalyst for the conversion process of glucose to its derivative compound in dimethylsulfoxide (DMSO) solvent. The result of the conversion process showed that glucose's mass decreased to the elevation of oil bath's temperature. The highest yield of 5-hydroxymethylfurfural is achieved at 140°C for 4 hours which the value is 12.832%. The reaction kinetic of glucose into 5-hydroxymethylfurfural is according to a first-rate equation with the activation energy was 253.949 kJ/mol.

Abstrak :
Pada penelitian ini, nanokomposit clay-epoxy menggunakan Organo clay Nanomer I30E, epoxy resin DER 331 dan curing agent Versamid 125 disintesa dengan metode in situ polimerization. Sebagai pembanding, komposit serat gelas-epoxy menggunakan serat gelas komersial dan epoxy resin dan curing agent yang sama disintesa dengan metode wet laminating. Karakterisasi struktur internal dan permukaan fracture, yang masing-masing menggunakan XRD (X-Ray Diffraction) dan SEM (Scanning Electron Microscope), menunjukkan bahwa nanokomposit telah berhasil disintesa. Nanokomposit memiliki struktur eksfoliasi pada komposisi clay <7.34 (% berat) dan struktur eksfoliasi dan interkalasi pada komposisi clay ≥ 7.34 (% berat). Nanokomposit dengan komposisi clay 2.10 (% berat) terdiri dari fasa epoxy dan fasa aglomerasi clay dan memiliki tanda fracture berbentuk kerucut. Hasil uji tarik, tekan dan kekerasan menunjukkan bahwa nanokomposit, yang disintesa dengan teknik pencampuran DM (Direct Mixing), tidak layak digunakan untuk aplikasi struktural pada pesawat terbang menggantikan komposit serat gelas-epoxy. Hasil uji tarik menunjukkan nanokomposit yang terbentuk memiliki perilaku yang sama dengan komposit particulate epoxy, yaitu tensile strength yang mengalami penurunan seiring dengan penambahan komposisi clay. Hasil uji tekan dan kekerasan masing-masing menunjukkan yield compression strength yang tidak mengalami perubahan dan kekerasan mengalami sedikit peningkatan, yang tidak tergantung pada komposisi clay, seiring dengan penambahan komposisi clay. ......In this observation, clay-epoxy nanocomposites using Nanomer I30E organo clay, DER 331 epoxy resin and Versamid 125 curing agent were synthesized with an in-situ polimerization method. As comparison, fiberglass-epoxy composites using commercial fiber glass and the same epoxy resin and curing agent were synthesized with wet laminating method. Characterization of internal structure and fracture morphology, using XRD (X-Ray Diffraction) and SEM (Scanning Electron Microscope) respectively, showed that nanocomposites had been successfully synthesized. Nanocomposites owned an exfoliated structure at clay composition <7.34 (% weight) and a mixture of exfoliated and intercalated structure at clay composition >7.34 (% weight). The nanocomposite with clay composition 2.10 (% weight) consisted of epoxy fase and clay agglomerates fase and owned cone shape fracture markings. The results of tensile, compression and hardness testings showed that nanocomposites, synthesized using DM (Direct Mixing) dispersion technique, was found not suitable for structural application in aircraft replacing fiberglass-epoxy composite. The result of tensile testing showed nanocomposite formed owned similar behavior to particulateepoxy composite, where the tensile strength experienced decrease as clay composition was increased. The results of compression and hardness testings showed that yield compression strength didn’t experience change and hardness experienced few increases, which was not affected by clay’s composition, as clay's composition increased.

Abstrak :
Tesis ini merupakan bahasan hasil penelitian fabrikasi material nanokomposit dengan perbaikan pada proses fabrikasi. Penelitian ini bertujuan untuk meningkatkan sifat mekanik dan termal dari material nanokomposit nanoclaypolipropilena melalui peningkatan panjang screw dalam mesin twin screw extruder (TSE). Screw pendek yang digunakan memiliki panjang 300 mm, sedangkan screw panjang ukurannya 600 mm. Formulasi dari nanokomposit adalah 3,5 % nanoclay dalam matrik polipropilena dengan aditif kompatibiliser 5 % PP-g-MA. Hasil pengamatan struktur mikro nanokomposit menggunakan scanning electron microscope (SEM) dan scanning probe microscope (SPM) menunjukkan bahwa hasil fabrikasi nanokomposit menggunakan mesin pencampur TSE screw panjang memiliki sebaran/dispersi nanoclay yang lebih baik dibanding hasil fabrikasi menggunakan screw pendek. Dari hasil pengujian sifat mekanik nanokomposit yang dilakukan yang meliputi kekuatan tarik, modulus kekakuan, kekerasan, ketahanan aus dan ketangguhan menunjukkan bahwa nanokomposit hasil fabrikasi menggunakan screw panjang sifat mekaniknyalebih baik. Modulus kekakuan meningkat 34 %, ketangguhan dan kekerasan meningkat 1 %,. Dampak positif dari penelitian ini adalah meningkatnya sifat termal nanokomposit hasil fabrikasi menggunakan screw panjang dari pada hasil fabrikasi menggunakan screw pendek, sifat termal yang dianalisis meliputi: temperatur dekomposisi, temperatur defleksi, kecepatan bakar dan temperature leleh. Bila dibandingkan dengan polipropilena, maka nanokomposit memiliki peningkatan sifat sdiantaranya termal defleksi 7 %, termal dekomposisi 2 % dan ketahanan bakar 8 %.

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This thesis is a discussion of material manufacturing nanocomposites with improvements in the manufacturing process. This research aims is to improve the mechanical and thermal properties of nanoclay-polypropylene nanocomposites material through the longer screw in the twin screw extruder (TSE) mixer machine. Short screw used own length of 300 mm, while the other screw length of 600 mm in size. Formulation of nanocomposites is 3.5% nanoclay in polypropylene matrix with compatibilizer of 5 % PP-g-MA. The results of micro structure of nanocomposites observed by scanning electron microscope (SEM) and scanning probe microscope (SPM) showed that the nanocomposites manufacturing using a long screw found that the dispersion of nanoclay in nanocomposites is better than fabricated using a short screw. The mechanical testing of nanocomposites materials includes a tensile strength, elastic modulus, hardness, impact, and wear resistance the results showed that the nanocomposites manufacturing use longer screw have increased of mechanical properties, elastic modulus improve 34 %, impact charpy and hardness improve 1 %,. The side effect of this research is thermal properties of nanocomposites manufacturing use long screw was increased compared nanocomposites manufacturing using short screw. The thermal properties has analysed by flammability, thermal decomposition, thermal deflection, and melting temperature. Compare to polypropylene, the nanokomposites as manufacture has improve thermal deflection 7 %, thermal decomposition 2 % and flame retardant 8 %.