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"Pencangkokan 4-vinilpiridin pada serat polipropilen dengan teknik radiasi, sebagai alternatif untuk membuat serat penukar ion telah dilakukan, Pengaruh kondisi radiasi, metoda pencangkokan, dosis, laju dosis, jenis pelarut, komposisi pelarut , dan konsentrasi monomer terhadap kadar pencangkokan dipelajari. Analisis dan karakterisasi serat polipropilen sebelum dan sesudah pencangkokan dilakukan dengan, ESR, FT-IR, DTAITGA, XRD, dan SEM-EDAX . Kapasitas penukaran serat PP-g-4VP terhadap ion Cue` dalam larutan analisis dengan ICP-MS.Hasil yang diperoleh dari ESR menunjukkan bahwa kondisi radiasi yang terbaik adalah oakum. Metoda yang memberikan kadar pencangkokan tertinggi adalah metoda simultan. Semakin tinggi dosis, laju dosis dan konsentrasi monomer, maka makin tinggi kadar pencangkokan. Makin menurun polaritas pelarut dalam pelarut homolog alkohol maka makin tinggi kadar pencangkokan, akan tetapi semakin tinggi kadar air didalam pelarut alkohol semakin tinggi kadar pencangkokan. Pelarut n-butanol menunjukkan kinetika pencangkokan lebih baik, dengan laju pencangkokan awal lebih tinggi di banding pelarut campuran metanol-air , Hubungan antara laju pencangkokan awal terhadap laju dosis dalam pelarut n-butanol adalah Rp = C I 0.35 ; sedangkan dalam pelarut metanol- air Rp = C I "7.Spektrum serapan FT-IR menunjukkan munculnya pita serapan vibrasi ulur u (C=C) dan u(C-H) aromatik pada bilangan gelombang 1625 dan 3020 cm-', dan pita serapan vibrasi ulur u (C-N) pada bilangan gelombang 1177 dan 1388 cm 1, yang berarti 4-vinilpiridin berhasil dicangkokan pada serat polipropilen. Pengamatan dengan SEM memperlihatkan perbedaan diameter dan permukaan serat polip ropilen sebelum dan sesudah dicangkok, sedangkan dari EDAX menunjukkan ion Cue+ telah diadsorpsi oleh serat PP-g-4VP dan terdistribusi secara merata, dengan kapasitas penukaran 3,4 mek/gram serat. Termogram DTAITGA menunjukkan pencangkokan 4-vinilpiridin pada serat polipropilen menunukkan kesetabilan termalnya, dan dari diffraktogram XRD menunjukkan terjadi perubahan fasa kristalin serat polipropilen setelah dicangkok.

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Influence of Solvents on Graft Copolymerization Kinetics of 4-vinilpiridin onto Polypropylene Fibers by Simultaneous Methods in Vacuum Atmosphere Radiation graft copolymerization of 4-vinilipiridin onto polypropylene fibers, for synthesis of ion exchange fibers has been done. The effect of radiation condition, graft methods, dose, dose rate, solvents and monomer concentrations on the grafting yields was also studied. Analysis and characterization of polypropylene fibers before and after grafting was done by ESR, FT-IR, DTAITGA, XRD and SEM-EDAX. The ion exchange capacity of PP-g-4VP fibers on Cue+ ion was determined by ICP-MS.

The ESR spectra showed that vacuum atmosphere was the best irradiation condition. The higher grafting yields were obtained by simultaneous method. The grafting yields increased with increasing dose, dose rate, monomer concentration and H2O content within alcohol-water solvents system. The grafting yields also increased if polarity of alcohol decreased in using homologue alcohol solvent system. The initial copolymerization rate in n-butanol solvents was higher than methanol-water solvents, with Rp = C 10.35 in n-butanol and, Rp = C I 0.57 in methanol-water solvents, Infra red spectra showed characteristic band sorption on wave length 1625 and 3020 cm 'I for C-H and C=C aromatic stretching, and 1177 and 1388 cm-' for C-N stretching. Observation by using SEM-EDAX showed the difference between polypropylene before and after grafted by 4-vinilpiridin, and Cue+ ion was homogeneously adsorbed by PP-g-4VP fibers, with adsorbed capacity 3.4 meg/gr. DTAITGA thermogram showed, that grafted 4-vinilpiridin onto polypropylene fibers was decreased its thermal stability, and X-ray diffractogram showed that crystalinity of polypropylene was changed after grafted by 4-vinilpiridin."

"Urgensi akan permasalahan limbah makin meningkat. Salah satu limbah yang paling sulit di olah adalah limbah plastik, maka kebutuhan akan plastik yang dapat di degradasi secara cepat menjadi salah satu alternatif solusi untuk permasalahan tersebut. Material berbahan dasar organik seperti serat ijuk dan polylactic acid mulai di kembangkan. Akan tetapi perbedaan sifat permukaan kedua bahan tersebut menimbulkan masalah apabila di padukan. Untuk mengatasi masalah kompatibilitas tersebut dibutuhkan perlakuan alkalinisasi pada kedua bahan tersebut. Alkalinisasi dilakukan dengan larutan NaOH 0,25 M dan 0.5 M selama 6 jam ,8 jam, dan 10 jam di harapkan dapat meingkatkan kompatibilitas antar 2 bahan tersebut. Kompatibiltas dapat di tunjukan melalui sifat mekanis material komposit tersebut. Mencari fraksi volum serat yang optimal menjadi suatu hal yang harus di lakukan karena dapat berpotensi menimbulkan void. Maka fraksi volume 5%, 7,5%, dan 10% menjadi variabel dalam penentuan fraksi volume yang optimal. ......Nowadays the urgency of the waste problem is increasing. One of the most difficult waste to be processed is plastic waste, the idea of plastic that can be degraded quickly become one of alternative solutions to these problems. materials such as organic fibers and polylactic acid bio-polymer begin to develop. However, differences in the surface properties of the two materials is become a problem to be solved. To overcome the compatibility issues, Fibers need alkalinization treatment on both of the materials. Alkalinization performed with NaOH solution 0.25 M and 0.5 M for 6 hours, 8 hours, and 10 hours are expected to boost the compatibility of surface properties between two materials. Good compatibility can be indicated through the mechanical properties of the composite material. Searching for the optimal fiber volume fraction becomes a thing that should be done because it can potentially resulting voids in the microstructure. Then the volume fraction of 5%, 7.5%, and 10% are the variables to determine the optimal volume fraction of the composite."

"Konsumsi polimer dalam jumlah besar, menekan industri polimer untuk menghemat bahan baku material dan mempercepat laju produksi. MFC berbasis serat alam telah dipelajari mampu memperbaiki sifat dan kecepatan laju proses dari polimer. Indonesia sebagai negara agraris memiliki banyak sumber serat alam, salah satunya serat ijuk. Melalui proses perlakuan, serat alam diproses hingga didapatkan MFC yang akan dipelajari sifatnya sebagai agen penukleasi didalam polimer polipropilena jenis kopolimer impak. Dengan penambahan MFC, dapat meningkatkan 2% kristalinitas dan kecepatan kristalinitas hingga 12 detik. Penelitian ini menitik beratkan pada kemampuan kristalinitas dari PP setelah ditambahakan MFC. ......Polymer comsumption in large scale, pushing polymer industry to reduce consumption of base material and increasing production time. ?Ijuk? based MFC has been studied can improve quality and accelerate process on PP. Indonesia as a maritime nation had many kind land riches, the one is ?ijuk? fiber. By conditioning process, ?ijuk? fiber made into MFC than have good bonding and will be studied his properties as nucleating agent on polymer polypropylene copolymer impact. With addiction of "

"A research was being done for analyzing strength and stiffness characteristic of two types of laminated fiber glass/aramid/epoxy composite material. Each type consists of eight and ten layers in same configuration with two different kinds of angle orientations. The base materials used in this research were glass epoxy and aramyd/epoxy fiber composites in which the epoxy is used as matrix. Some mechanical tests and optical observation was carried out for analyzing its macro and micro mechanical characteristics for both types. From the result of mechanical test, it was found that the compressive strength, stiffness and impact characteristic of the second type was better than the first type, but its tensile strength was slightly lower then the first type. In impact test for both type, there was found an increasing in impact strength by decreasing the temperature from 27 °C to -10 °C, which at temperature was -10 °C the both of material was becoming brittle. Optically, it was found that the second type more rigid than first type by observing the shape and direction of its fracture."

"ABSTRACT As transmission medium in optical communication system, optical fiber is also characterized by elastic properties beside of transmission properties of optical fiber. The Young Modulus of Elasticity of optical fiber could be measured by considering a bare optical fiber as cantilever which resonant with an acoustical vibration. To detect the cantilever vibration, a HeNe laser light is launched into the cantilever of optical fiber through its free end and the output laser light is detected by a PMT and observed by the channel 2 of an oscilloscope. Channel 1 of the oscilloscope observes the signal of the acoustical vibration. Regulating both the frequency and amplitude of the vibration or the position of the pinhole of the PMT, the resonance frequency of the cantilever could be detected accurately. Using the data of the resonance frequencies of various length of the cantilever has been calculated. "

"ABSTRAKIn transmission system, the information to be transmitted from one source to several addressed receivers requires a component to distribute the information. To achieve an efficient and simple distribution circuit of information, a study on the use of fiber as information signal distributor without using other optical elements has been developed as a fiber star-coupler. The optical fiber star-coupler was constructed by chemically processing the end face of fiber into a cone-shaped. The process was carried out by chemical treatment for unjacketed fibers using HF solution. The optical signal distributed to the outgoing fibers will have as higher intensity as the nearer the fiber to the optical axis. An efficient fiber star-coupler can be achieved by arranging the optimum number of receiving fibers correspond to coupling distance and numerical aperture of the optical fibers."

"In signal transmission through an optical fiber, a bending fiber causes degradation of efficiency. Due to mode conversion and radiation loss. Considering a light power radiated from a bending fiber has a possibility to be utilized as detectable signal, it is proposed an optical tap by using bending fiber.The study is devoted to design and construction of optical tap for fiber link, without any other optical element. The signal quality of the radiated light from optical fiber bending has been investigated in various angle of detection and in various radius of curvature. The result shows that the radiated signal has similar shapes of distribution of 20 degrees. And the bending loss increases if the radius of curvature decreases.A trial of sending optical signal from one end of the fiber link shows a detected radiated signal from the bending point. It is predicted that the bending fiber can be applied as optical tap, instead of a source of power loss."

"Saat ini penggunaan material berbasis polimer semakin meningkat seiring dengan pertumbuhan populasi manusia. Kebutuhan akan material berbasis polimer tersebut didasari oleh harga yang relatif murah dan fungsinya serba guna. Polimer berbasis pada minyak bumi merupakan jenis polimer yang sulit untuk diuraikan oleh mikroorganisme sehingga dibutuhkan material polimer alternative yang berasal dari alam untuk mengatasi isu lingkungan tersebut. Poly Lactic Acid (PLA) merupakan salah satu polimer alam yang cukup banyak digunakan. Namun PLA memiliki sifat mekanik dan ketahanan termal yang kurang baik, sehingga dibutuhkan pengisi dari bahan alam seperti serat ijuk untuk meningkatkan sifat mekanik. Pada penelitian ini dilakukan percobaan untuk mengetahui kompatibilitas pengisi dan matriks, konsentrasi optimal pemutihan serat, waktu optimal pemutihan serat dan komposisi optimal antara pengisi dan matriks. Pengamatan dilakukan terhadap morfologi permukaan serat ijuk dan fraktografi material komposit menggunakan FE-SEM, mengetahui perubahan kristalinitas serat ijuk menggunakan X-RD, mengetahui gugus fungsi dari serat ijuk untuk melihat kandungan lignin dan hemiselulosa menggunakan FTIR serta kekuatan tarik material komposit menggunakan micro-tensile. Hasil dari penelitian ini yaitu pemutihan dapat meningkatkan kompatibilitas pengisi dan matriks, konsentrasi optimal pemutihan adalah 7,5% NaClO selama 2 jam dan waktu optimal pemutihan adalah 1 jam dengan 10% NaClO. Dengan penambahan komposisi ijuk 10%, 20%, 30% ke dalam matriks PLA maka kekuatan tarik material komposit semakin meningkat. ......Nowadays, The necessity of polymer-based material is getting higher because of its versatile utilization and relatively low cost. Petroleum polymer is difficult to be processed by micro-organism so that the alternative natural polymer is required to tackel this issue. Poly Lactic Acid (PLA) is one of the polymer used in many industries but PLA has the poorness on its mechanical properties and thermal resistance. Therefore, the addition of reinforcement such as ijuk fiber can be used to optimize its properties. In this research, the compability of reinforcement and matrix, the optimum concentration of bleaching, the time of bleaching and the composition of reinforcement and matrix are studied. Visual observation on the morfology and fractography of ijuk fiber surface was performed using FE-SEM, the crystallinity of ijuk fiber was conducted using XRD, the functional group of ijuk fiber was carried out using FTIR to examine lignin and hemi-cellulose content and the tensile test of this composite material was performed using micro-tensile test. From the data, it was acquired that bleaching enhance the compability between filler and matrix, the optimum concentration of bleaching is 7,5% NaClO for 2 hours and the optimum time of bleaching is 1 hour with 10% NaClO. In the mechanical properties aspect, it is obtained that as the higher ijuk addition, from 10% to 30%, into the PLA matrix, the tensile strength of the composite is improve."

"Arah orientasi dari material karbon fiber sangat berperan penting dalam kekuatannya. Penelitian ini bertujuan untuk menganalisis kekuatan dari bodi dari mobil Keris RVIII setelah dilakukan inovasi dalam arah orientasi struktur komposit dari material. Penelitian ini juga bertujuan untuk melihat pengurangan berat dan biaya dari hasil desain bodi yang baru. Penelitian ini harus memenuhi regulasi dari Shell Eco Marathon dalam pemenuhan dimensi dari bodi dan kebutuhan zona crumple yaitu sebesar 100 mm dari bagian depan kendaraan hingga ke kaki driver. Pendesainan bodi dibuat menggunakan perangkat lunak Autodesk Inventor 2022 dan disimulasikan menggunakan perangkat LS-DYNA menggunakan analisis crashworthiness. Pengujian bodi menggunakan kecepatan maksimal kendaraan yaitu 40 km/h dengan jenis tuimbukan yang terjadi adalah front impact dengan media tabraknya adalah tembok dengan material concrete. Pada pengujian bodi ada dua variasi yang diujikan yaitu arah orientasi karbon fiber dan variasi dari ketebalan pada bodi enam dan tujuh lapis karbon fiber Peneliti melakukan pengujian spesimen terlebih dahulu untuk memastikan validitas dari simulasi. Untuk uji spesimen terdapat tiga bentuk spesimen yang diujikan yaitu plat, tube, dan peluru. Pada pengujian spesimen juga dilakukan variasi dari arah karbon. Dari hasil uji spesimen maka peneliti menemukan adanya faktor bentuk yang akan mempengaruhi hubungan dari arah komposit dan deformasi yang terjadi pada spesimen. Setelah mengetahui adanya faktor bentuk dari desain, penelitian dilanjutkan dengan menganalisis bodi dari desain yang baru. Dari simulasi yang bodi dilakukan maka akan didapat hasil deformasi yang memiliki bentuk grafik yang mirip dengan spesimen peluru, ini menunjukan bahwa faktor bentuk dari spesimen sudah relevan. Hasil simulasi yang diujikan pada bodi sudah memenuhi regulasi dengan menggunakan arah orientasi pada sudut 60 derajat dengan ketebalan tujuh lapis karbon fiber dengan angka deformasi sebesar 85,1 mm dan arah orientasi pada sudut 90 derajat dengan ketebalan tujuh lapis karbon fiber dengan angka deformasi sebesar 78,3 mm. Hasil penurunan berat yang didapatkan pada desain baru adalah sebesar 13% dari berat bodi aktual, sedangkan untuk pengurangan biaya didapatkan angka sebesar 19% dari biaya bodi aktual.......The orientation direction of carbon fiber material plays a crucial role in its strength. This research aims to analyze the strength of the body of the Keris RVIII car after implementing innovations in the orientation direction of the composite structure material. The study also aims to examine the reduction in weight and cost resulting from the new body design. This research must comply with the regulations of the Shell Eco Marathon regarding the body dimensions and the crumple zone requirement, which is 100 mm from the front of the vehicle to the driver's feet. The body design is created using Autodesk Inventor 2022 software and simulated using LS-DYNA software for crashworthiness analysis. The body testing is conducted at the maximum vehicle speed of 40 km/h, with a front impact collision against a concrete wall. Two variations are tested in the body experiments: carbon fiber orientation and thickness variation in the body using six and seven layers of carbon fiber. The researchers perform preliminary specimen testing to ensure the validity of the simulations. Three specimen shapes are tested: plate, tube, and bullet, with variations in the carbon fiber orientation. From the specimen testing results, the researchers discover the influence of shape factors on the relationship between composite orientation and deformation in the specimens. After identifying the shape factors in the design, the study continues by analyzing the new body design. The simulation of the body yields deformation results that have a similar graph shape to the bullet specimen, indicating the relevance of the shape factors. The simulation results tested on the body comply with the regulations when using a 60-degree orientation angle and a seven-layer thickness of carbon fiber, resulting in a deformation of 85.1 mm. Similarly, a 90-degree orientation angle with a seven-layer thickness of carbon fiber results in a deformation of 78.3 mm. The weight reduction achieved in the new design is 13% of the actual body weight, while the cost reduction amounts to 19% of the actual body cost."