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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 nanoclay- polipropilena 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

Abstrak :
Pada penelitian ini telah berhasil disintesis nanokomposit berupa gabungan dari graphene oxide (GO)−Kitosan dan modifikasi dengan nanopartikel Fe3O4 menggunakan teknik kopresipitasi untuk aplikasi adsorpsi tetrasiklin, yang mana antibiotik ini dapat menyebabkan peningkatan resistensi antibiotik (ARG) pada lingkungan ekosistem perairan. Nanokomposit yang telah disintesis dikarakterisai dengan FTIR, XRD, SEM, BET, dan TEM dan diperoleh luas permukaan nanokomposit 76,644 m²/g (BET) dan ukuran partikel 12,112 nm (TEM). Nanokomposit yang berhasil diperoleh diaplikasikan sebagai adsorben dan dilakukan studi adsorpsi dan pengukuran absorbansi tetrasiklin dilakukan dengan spektrofotometer UV-Vis untuk mendapatkan nilai kapasitas adsorpsi dan persen adsorpsi. Kondisi optimum diperoleh pada pH 6, dengan variasi molar nanokomposit Fe3O4 NP 0,2 M : 0,1 M)/GO−Kitosan, massa 30 mg, waktu 90 menit, dan konsentrasi awal tetrasiklin 25 mg/L pada suhu 25 oC. Kapasitas adsorpsi dan persen adsorpsi yang terbaik masing-masing sebesar 38,1540 mg/g dan 91,57%. Hasil studi kinetika didapat bahwa proses adsorpsi ini mengikuti model kinetika pseudo orde dua, sedangkan untuk hasil studi isoterm adsorpsi didapat bahwa reaksi mengikuti model isoterm Langmuir. Usulan mekanisme adsorpsi tetrasiklin menggunakan nanokomposit Fe3O4/ GO−Kitosan adalah dengan interaksi elektrostatik, ikatan hidrogen, dan interaksi π-π. Oleh karena itu, pengembangan nanokomposit berbasis GO−Kitosan yang ramah lingkungan menjanjikan untuk adsorben dan fotokatalis di masa depan. ......In this study, nanocomposites were successfully synthesized in the form of a combination of graphene oxide (GO)−Chitosan and modification with Fe3O4 nanoparticles using coprecipitation techniques for tetracycline adsorption applications, in which this antibiotic can cause an increase in antibiotic resistance genes (ARG) in aquatic ecosystems. The synthesized nanocomposites were characterized by FTIR, XRD, SEM, BET, and TEM and obtained a surface area of the nanocomposite of 76,644 m²/g (BET) and a particle size of 12,112 nm (TEM). The obtained nanocomposites were applied as adsorbents and adsorption studies were carried out and tetracycline absorbance measurements were carried out with a UV-Vis spectrophotometer to obtain adsorption capacity values and adsorption percentages. Optimum conditions were obtained at pH 6, with molar variation of Fe3O4 NP 0,2 M : 0,1 M)/GO−Chitosan, mass 30 mg, time 90 minutes, and initial concentration of tetracycline 25 mg/L at 25 oC. The best adsorption capacity and adsorption percentage were 38.1540 mg/g and 91.57%, respectively. The results of the kinetic study found that the adsorption process followed the pseudo second order kinetic model, while the results of the adsorption isotherm study found that the reaction followed the Langmuir isotherm model. The proposed tetracycline adsorption mechanism using the Fe3O4/GO−Chitosan nanocomposite is by electrostatic interactions, hydrogen bonds, and π-π interactions. Therefore, the development of environmentally friendly GO-Chitosan-based nanocomposites is promising for adsorbents and photocatalysts in the future.

Abstrak :
In recent years, much attention has been focused on biodegradable polymers from renewable resources. Due to its availability and low cost, starch is a promising candidate among biopolymers for use in biodegradable packaging materials and for other purposes. Starch-Based Polymeric Materials and Nanocomposites: Chemistry, Processing, and Applications presents the latest developments in starch chemistry, rheology, starch derivatives, starch-based nanocomposites, and their applications.Topics discussed include:The chemistry, microstructure, processing, and enzymatic degradation of starchThe importance and role of starch as a gelling agentPlasticization and the role of plasticizersVarious rheological techniques applied to starch-related products and the characteristics of starch dispersionsPolymeric aspects of reactive extrusion (REX) and its use on starch and other biopolymersCyclodextrins (CDs) and their industrial applications, and CD-based supramole and polymersThe potential of starch in food packaging, edible packaging, feedstock for bioproducts, and industrial and consumer productsThe theoretical basis and derivation of the mathematical model for multicomponent systems and its solution algorithmThe book also explores recent progress in biodegradable starch-based hybrids and nanomaterials and the incorporation of nanoparticles in starches to enhance their mechanical and thermal properties. The book concludes by discussing the use of biopolymeric nanoparticles (BNPs) in drug delivery and life cycle assessment (LCA) of starch-based polymeric materials for packaging and allied applications.With contributions from leading experts in academia and industry, this volume demonstrates the versatility of starch and its potential in a variety of applications.

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Springer Berlin Springer

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[Environmental silicate nano-biocomposites focuses on nano-biocomposites, which are obtained by the association of silicates such as bioclays with biopolymers. By highlighting recent developments and findings, green and biodegradable nano-composites from both renewable and biodegradable polymers are explored. This includes coverage of potential markets such as packaging, agricultures, leisure and the fast food industry. The knowledge and experience of more than twenty international experts in diverse fields, from chemical and biochemical engineering to applications, is brought together in four different sections covering : biodegradable polymers and silicates, clay/polyesters nano-biocomposites, clay/agropolymers nano-biocomposites, and Applications and biodegradation of nano-biocomposites. By exploring the relationships between the biopolymer structures, the processes, and the final properties Environmental silicate nano-biocomposites explains how to design nano-materials to develop new, valuable, environmentally friendly properties and uses. , Environmental silicate nano-biocomposites focuses on nano-biocomposites, which are obtained by the association of silicates such as bioclays with biopolymers. By highlighting recent developments and findings, green and biodegradable nano-composites from both renewable and biodegradable polymers are explored. This includes coverage of potential markets such as packaging, agricultures, leisure and the fast food industry. The knowledge and experience of more than twenty international experts in diverse fields, from chemical and biochemical engineering to applications, is brought together in four different sections covering : biodegradable polymers and silicates, clay/polyesters nano-biocomposites, clay/agropolymers nano-biocomposites, and Applications and biodegradation of nano-biocomposites. By exploring the relationships between the biopolymer structures, the processes, and the final properties Environmental silicate nano-biocomposites explains how to design nano-materials to develop new, valuable, environmentally friendly properties and uses. ]

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ABSTRAK
Nanoparticle SnO2 dan nanocomposites SnO2/NGP dengan variasi weight percent wt dari NGP 5wt , 10wt dan 15wt masing-masing disintesis menggunakan metode sol gel dan co-precipitation. Sifat degradasi termal, morfologi dan struktur dianalsis menggunakan spectroscopy TGA Thermogravimetric Analysis , XRD Xray Diffraction , TEM Transmission Electron Spectroscopy , FTIR Fourier Transform Infrared , serta EDX Energy Dispersive X-ray . Dari pengukuran EDX diketahui bahwa keberadaan dari atom C pada nanokomopsit SnO2/NGP mengonfirmasi adanya material NGP pada nanocomposites. Luas permukaan SnO2 nanoparticle meningkat seiring dengan peningkatan wt NGP pada nanocomposites. Pengujian aktivitas photo-, sono-, dan sonophoto- catalytic sampel nanoparticle dan nanocomposites dilakukan dengan mengamati degradasi warna methylene blue MB masing-masing dibawah pemaparan cahaya ultraviolet, ultrasonic, dan gabungan keduanya. Seiring dengan penambahan wt NGP aktivitas photo-, sono-, dan sonophoto- catalytic nanocomposites menjadi semakin meningkat. pH optimum larutan uji diperoleh pada pH 13, serta spesies yang paling berperan dalam aktivitas photo-, sono- dan sonophoto- catalytic adalah hole>OH radikal>elektron.

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ABSTRACT
SnO2 nanoparticle and SnO2 NGP nanocomposites with various weight percent wt of NGP 5wt , 10wt and 15wt were successfully prepared by sol gel and co precipitation method, respectively. Thermal degradation properties, morphology and structural properties were characterized using TGA Thermogravimetric Analysis , XRD X ray Diffraction , TEM Transmission Electron Spectroscopy , FTIR Fourier Transform Infrared , and EDX Energy Dispersive X ray . From EDX results show that the addition of C atomic in SnO2 NGP nanocomposite could be confirm the existence of NGP content in nanocomposites. Surface area of SnO2 nanoparticle increase with the increasing of wt NGP in nanocomposites. Photo , sono and sonophoto catalytic examination of the nanoparticle and nanocomposites was carried out using aqueous solution of methylene blue MB under ultraviolet, ultrasonic and combination of both irradiation, respectively. The highest photo , sono and sonophoto catalytic occurred with sampel SnO2 NGP 10wt nanocomposite at alkaline condition. The main species which contributed in photo , sono and sonophoto catalytic activity were hole hydroxyl radical electron.

Abstrak :
Metode hidrotermal telah diterapkan dalam pembuatan katalis nanokomposit Ag/CeO2 dengan tiga variasi rasio molar katalis nanopartikel CeO2 dan penambahan graphene pada nanokomposit dengan variasi tiga persen berat (wt.%). Kotoran dan fase lain dalam sampel tidak ditemukan dalam pengukuran Difraksi sinar-X (XRD) dan fluoresensi sinar-X (XRF). Keberadaan graphene dikonfirmasi oleh pengukuran Thermal Gravimetric Analysis (TGA) dan Raman Spectroscopy. Luas permukaan spesifik nanokomposit terbesar diperoleh untuk rasio molar CeO2 1:2 dan peningkatan 10wt.% pada graphene berdasarkan hasil pengukuran BET. Tiga jenis proses katalitik yang digunakan untuk mendegradasi Methylene Blue (MB), yaitu sonocatalytic (paparan gelombang ultrasonik), fotokatalitik (paparan sinar tampak dan ultraviolet), dan kombinasi keduanya (sonophotocatalytic). Degradasi maksimum MB diperoleh untuk variasi rasio molar 1:2 dengan 5 wt.% graphene untuk dosis 0,5 g/L dengan konsentrasi MB 20 mg/L pada pH larutan 13 untuk ketiganya. jenis proses katalitik. Mekanisme degradasi maksimum MB dalam proses sonofotokatalitik untuk katalis nanokomposit graphene Ag/CeO2/5 wt.% adalah kontribusi kekosongan oksigen, luas permukaan spesifik, adanya resonansi plasmon permukaan (SPR) dan situs aktif. Spesies aktif lubang yang berperan dalam proses katalitik yang melibatkan cahaya yaitu proses fotokatalitik dan sonofotokatalitik, sedangkan radikal hidroksil merupakan spesies yang berperan aktif dalam proses sonokatalitik.
The hydrothermal method has been applied in the manufacture of Ag/CeO2 nanocomposite catalysts with three variations of the molar ratio of the CeO2 nanoparticle catalyst and the addition of graphene to the nanocomposite with a variation of three percent by weight (wt.%). Impurities and other phases in the sample were not found in X-ray diffraction (XRD) and X-ray fluorescence (XRF) measurements. The existence of graphene was confirmed by Thermal Gravimetric Analysis (TGA) and Raman Spectroscopy measurements. The largest specific surface area of ​​nanocomposite was obtained for CeO2 1:2 molar ratio and 10wt.% increase in graphene based on BET measurement results. Three types of catalytic processes are used to degrade Methylene Blue (MB), namely sonocatalytic (exposure to ultrasonic waves), photocatalytic (exposure to visible and ultraviolet light), and a combination of both (sonophotocatalytic). The maximum degradation of MB was obtained for a variation of the molar ratio of 1:2 with 5 wt.% graphene for a dose of 0.5 g/L with a concentration of MB 20 mg/L at a solution pH of 13 for all three. type of catalytic process. The maximum degradation mechanism of MB in the sonophotocatalytic process for Ag/CeO2/5 wt.% graphene nanocomposite catalyst is the contribution of oxygen vacancies, specific surface area, presence of surface plasmon resonance (SPR) and active sites. Active species of holes that play a role in catalytic processes involving light are photocatalytic and sonophotocatalytic processes, while hydroxyl radicals are species that play an active role in sonocatalytic processes.

Abstrak :
Health and environmental safety of nanomaterials addresses concerns about the impact of nanomaterials on the environment and human health, and examines the safety of specific nanomaterials. Understanding the unique chemical and physical properties of nanostructures has led to many developments in the applications of nanocomposite materials. While these materials have applications in a huge range of areas, their potential for toxicity must be thoroughly understood. Part one introduces the properties of nanomaterials, nanofillers, and nanocomposites, and questions whether they are more toxic than their bulk counterparts. Part two looks at the release and exposure of nanomaterials. The text covers sampling techniques and data analysis methods used to assess nanoparticle exposure, as well as protocols for testing the safety of polymer nanocomposites. It explains characterization techniques of airborne nanoparticles and life cycle assessment of engineered nanomaterials. Part three focuses on the safety of certain nanomaterials, including nanolayered silicates, carbon nanotubes, and metal oxides. In particular, it explores the potential ecotoxicological hazards associated with the different structures of carbon nanotubes and the safe recycling of inorganic and carbon nanoparticles. The final two chapters address the risks of nanomaterials in fire conditions, their thermal degradation, flammability, and toxicity in different fire scenarios.

Abstrak :
Low linear density polyethylene/organo-montmorillonite (LLDPE/OMMT) nanocomposites at 1–5 wt% OMMT loading were prepared by the melt intercalation technique. The OMMT was synthesized via an ion exchange reaction by replacing the interlayer of sodium ions (Na+ ) in the repeating unit of silicate layers of montmorillonite (MMT) with the cationic surfactant in the form of trihexyltetradecylphosphonium (THTDP) ions. The obtained OMMT and its nanocomposites were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and elemental and thermogravimetric analyses. The interlayer spacing of MMT expanded from 1.41 to 2.29 nm due to the accommodation of THTDP ions in the intergallery of OMMT. The introduction of THTDP in the interlayer of OMMT rendered better dispersion of OMMT layers in the LLDPE/OMMT nanocomposites and significantly improved the thermal degradation properties of nanocomposites as compared to the pristine LLDPE.

Abstrak :
Nanocomposites of zinc-aluminium-anthranilate (ZAAN) have been synthesized at different concentrations of anthranilic acid by co-precipitation method. These materials have been examined in detail by powder X-ray powder diffraction (PXRD) which showed the expansion of the basal spacing from 0.89 to ca. 1.33 nm and the shifting of the 003 peak towards the lower 2q angle. This indicates that the anthranilate anion was successfully intercalated into the interlayer gallery. However, FTIR analysis showed nitrate anion was also co-intercalated in the interlayer. The resulting nanocomposites show Type IV adsorption-desorption isotherms indicated the mesoporous structure of the material. BET surface area was found to be slightly different compared to zinc-aluminium-nitrate-layered double hydroxide (ZANO) after the intercalation process took place. Both ZANO and ZAAN have similar surface morphology, namely a flaky-like structure, but they are of different sizes.