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Abstrak :
Saat ini telah dikembangkan suatu metode komposit yang dikenal dengan PMC (Polime memenuhi criteria untuk bahan fuel cell baik dari mechanical properties maupun electrical properties. Karakteristik Carbon Graphite yang keras dan kuat. dan Resin Phenolic yang ringan dan ulet merupakan properties yang memenuhi untuk produk membran komposit yang berupa graphite bipolar plate maka kedua material tersebut sangat tepat jika digabungkan menjadi komposit yang baru yaitu komposit matrik polimer (PMC) melalui proses Powder Metalurgi (P/M) Membran polimer merupakan komponen yang sangat penting dalam PEMFC mengingat peran komponen ini dalam memisahkan reaktan dan menjadi sarana transportasi ion hydrogen (proton)(4) yang dihasilkan oleh reaksi anoda menuju katoda sehingga reaksi katoda yang menghasilkan energi listrik dapat terjadi. Sehingga dibutuhkan bahan membrane yang memenuhi properties yang dibutuhkan untuk Fuel Cell. Graphite bipolar plate sebagai membrane fuel cell dipengaruhi oleh mekanisme proses pembuatanya dan variable dari proses tersebut. Proses pemanasan sintering dan Proses kompaksi merupakan variable mutlak dalam mekanisme proses powder metalurgi. Disamping itu juga fraksi volume dari komposisi bahan yang dipadukan. Penelitian ini menekankan pada pengaruh Sintering dan kompaksi pada karakteristik graphite bipolar plateFuel Cell hasil proses Metalurgi Serbuk. Material yang digunakan adalah serbuk Resin Phenolic sebagai matriksnya dan serbuk grafit sebagai reinforcenya. Dalam penelitian ini untuk metode pembuatan PMC dengan proses Metalurgi Serbuk menggunakan variable proses temperature sintering 100:200dan 300 °C dan penekanan kompaksi 100:200 dan 300 bar serta fraksi volume 50:50% 60:40% dan 70:30%. Penelitian ini bertujuan untuk mengamati pengaruh temperatur sintering dan kompaksi terhadap karakterisasi dari komposit graphite bipolar plate yang meliputi pengujian kekerasan, kuat tekan, densitas, porositas,konduktifitas listrik, mikroskop optik dan SEM/EDS pada PMC Graphite bipolar plate dengan proses Metalurgi Serbuk. Dari hasil penelitian ini diperoleh bahwa dengan pemanasan temperatur sintering mendekati Tg (200 ºC) dari Matriks polimer maka akan meningkatkan mechanical properties dari komposit matrik Polimer. Dan pada penekanan maksimum akan meningkatkan electrical properties yang merupakan spesifikasi karakter dari graphite bipolar plate.

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Recently it has developed by a new material that was known as PMC (Polymer Matrix Composite) for bipolar plate fuel cell which produced by compaction of two powders i.e. phenolic resin and graphite with carbon black. The process used is powder metallurgy. The characterization of the material including mechanics & physical properties has investigated. Characteristically carbon graphite that hard and strong and Phenolic Resin that light and tenacious was properties that met for the membrane product composite that take the form of graphite bipolar plate then second material this was very exact if being united to composite that just that is composite matrix the polymer (PMC) through the process Powder Metallurgy (P/M). The polymer Membrane was the component that very important in PEMFC and DMFC remembered the role of this component in separating the reactant and becoming transport means of the ion hydrogen (the proton) that was produced by the reaction of the anode towards the cathode so as the reaction of the cathode that produced electricity energy could happen. So as to be needed the material membrane that met properties that was needed for Fuel Cell. Graphite bipolar plate as membrane fuel cell was influenced by the mechanism of the process him and variable from this process. The process compaction and the heating sintering was variable absolute in the mechanism of the process powder metallurgy. Nearby same the volume faction from the material composition that was combined. This research stressed the Sintering influence and compaction in the characteristics graphite bipolar plate. Fuel Cell results of the process of Dust Metallurgy. Materials that was used was Phenolic Resin dust as his matrix and graphite dust as reinforce him. In this research for the PMC production method with the process of Dust Metallurgy used variable the process temperature sintering 100:200dan 300 and the emphasis compaction 100:200 and 300 bar as well as the volume fraction 50:50% 60:40% and 70:30% This research aimed at observing the influence of the temperature sintering and compaction towards the haracterization from composite graphite bipolar plate that covered the testing of the violence, strong pressed, the density, the porosity, conductivity electricity, the optic microscope and SEM/EDAX to PMC Graphite bipolar plate with the process of Dust Metallurgy. From results of this research was received that with the heating of the temperature sintering approached tg (200 ºC) from the polymer Matrix then will increase mechanical properties from composite matrix the Polymer. And in the maximum emphasis will increase electrical property that was the specification of the character from graphite bipolar plate.

Abstrak :
Tingginya penggunaan material polimer dengan matriks komposit (PMC) dalam berbagai aplikasi akhir ? akhir ini menimbulkan permasalahan baru terkait dengan ketebatasan sumber daya dalam memenuhi kebutuhan yang terus berkembang dan pengaruhnya terhadap lingkungan. Salah satu jalan keluarnya adalah mencoba mencari material PMC alternatif yang lebih ramah lingkungan serta memiliki kekuatan yang baik yaitu material komposit dengan matriks polimer berpenguat serat alam. Salah satu matriks untuk material PMC yang sering digunakan dan mudah dalam proses fabrikasinya adalah resin poliester tidak jenuh, matriks ini kemudian ditambahkan serat rami yang merupakan salah satu serat alam dengan kapasitas produksi dunia mencapai 100,000 ton pertahun. Pada penelitian ini ingin diketahui pengaruh fraksi volum serat rami terhadap kekuatan impak, kekuatan tekuk dan kekuatan tekan material komposit. Fraksi volum rami yang digunakan antara 15% - 35% dengan interval 5%. Proses fabrikasi dilakukan dengan menggunakan metode hand lay up, yang dikombinasikan dengan penambahan tekanan selama proses curing. Hal ini dikarenakan metode hand lay up merupakan metode paling sederhana dalam proses pembuatan komposit walaupun memiliki beberapa catatan tekait kualitas material komposit yang dihasilkan berupa ketidak-merataan matriks dan ketidaklurusan serat. Penambahan konsentrasi serat rami terhadap material komposit rami ?poliester secara umum memberikan pengaruh berupa peningkatan ketahanan impak dan kekuatan tekuk. Sedangkan untuk kekuatan tekan walaupun dari grafik hasil pengujian terlihat adanya peningkatan, namun kekuatan tekan material komposit rami ? poliester masih sangat rendah jika dibandingkan dengan material lain bahkan dibawah kekuatan material poliester murni. Hal ini dikarenakan rendahnya kualitas material komposit hasil fabrikasi dengan metode hand lay up. Nilai optimum konsentrasi serat pada penelitian ini terdapat pada konsentrasi serat rami 35 % Vf. Yaitu dengan kekuatan impak rata ? rata sebesar 82.38 KJ/m2, kekuatan tekuk rata ? rata sebesar 125 MPa dan kekuatan tekan rata?rata sebesar 80.22 MPa.

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The highly use of polymer matrix composite (PMC) in various application this days has caused another issues like environment and limited natural resources. One of the way out is to find alternative PMC materials which have good properties and also environment friendly like natural fiber reinforced composite (NFRC) Polyester is one of PMC matrix which has widely use in composite with various fiber and jute as fiber is natural fiber which production scale in the whole country extend one hundred million tons in one year. The purpose of this research is to know effect of jute fiber concentration on mechanical properties of jute polyester composite such as impact resistance, flexural strength and compressive strength. For fabrication, hand lay up process combining compressive load during curing time is used. This is because the hand lay up is the most simply method in accordance to making PMC. Although this method has some notes related to quality product such as fiber misalignment and matrix distributed. The addition of jute concentration in jute ? polyester composite has increased the value of impact resistance and flexural strength. While for compressive test decreased because of fabrication product by hand lay up method has low quality surface performance, compressive strength of jute polyester composite is very low compare to another materials even pure unsaturated polyester resin has higher compressive strength than jute ? polyester composite. The optimum volume fraction in this research is held by 35 % Vf of jute fiber concentration with impact resistance 82.38 KJ/m2, Flexural strength rate 125 MPa and compressive strength of material 80.22 MPa.

Abstrak :
Komposit yang dikenal dengan PMC (Polymer Matrix Composite) telah lama dikembangkan. Komposit jenis ini dapat memenuhi kriteria untuk sel bahan bakar baik dari sifat mekanikal ataupun elektrikal. Material polimer thermoplastik seperti halnya ABS ( Acrylonitril Butadiene Styrene ) sifatnya yang cukup ringan dan ulet bila diperkuat dengan karbon grafit yang keras dan ulet serta kompensasi berat melalui pengkayaan grafit dengan carbon black dapat menghasilkan sistem komposit berupa graphite bipolar plate untuk aplikasi sebagai sel bahan bakar. Bipolar plate merupakan komponen yang sangat penting dalam sistem Proton Exchange Membran Fuel Cell berperan untuk menghindari bercampurnya oksigen dan bahan bakar hidrogen. Pada penelitian ini telah berhasil dibuat pelat bipolar sebagai bagian suatu sistem sel bahan bakar berbasis PEMFC ( Proton Exchange Membrane Fuel Cell ). Material campuran grafit/carbon black dan ABS dicampur dengan pelarut pelarut MEK ( Metyl Etyl Keton) dalam suatu reaktor batch dan dibantu peralatan Ultrasonic stirrer pada temperatur operasional sekitar 60°C. Komposit pelat dengan komposisi 75:25%, 60:40% dan 50:50% (fraksi volume) diperoleh melalui hot pressing compression pada tekanan 100, 150, 200 bar dengan temperatur 175, 200 dan 225°C. Pada penelitian ini juga dipelajari pengaruh temperatur heating dan kompaksi terhadap karakterisasi dari komposit graphite bipolar plate yang meliputi pengujian kuat tarik, kuat tekan, flexural strength, kekerasan, densitas, porositas, konduktivitas listrik dan struktur internal bipolar plate. Dari hasil penelitian ini diperoleh bahwa dengan pemanasan temperatur mendekati (225°C) sifat mekanik kuat lentur meningkat rata - rata 22 %. Konduktivitas listrik tertinggi diperoleh dari komposit dengan komposisi 75 : 25. Komposit bipolar plate dengan komposisi 40 : 60 , yang diperoleh melalui pemanasan pada temperatur 225°C dan penekanan 200 bar merupakan komposit yang paling memenuhi spesifikasi bipolar plate yang digunakan secara luas. ......The so called Polymer Matrix Composite, PMC is a well developed composite materials. The PMC is considered able to fulfil requirement mechanically and electrically for fuel cell bipolar plate applications. Although, thermoplastic polymer like ABS ( Acrylonitril Butadiene Styrene ) is light and soft materials, however, when reinforced by hard and tough graphites, enriched further by carbon black this should resulted in a composite system which suitable for graphite bipolar plates fuel cell applications. Bipolar paltes is one of most importnat component in Proton Exchange Membran Fuel Cell system acting to prevent oxygen and hydrogen gasses mixing. This research is aiming at observing the influence of heating temperature and pressure especially on mechanical and physical properties of bipolar plates. The electrical conductivity of the plates is another objectives of current research work. The research works have succeded to prepare a bipolar plate for PEMFC ( Proton Exchange Membrane Fuel Cell). Graphite and carbon black powder as well as ABS matrix were mixed together with MEK (Methyl Ethyl Ketone) solvent in an ultrasonic stirrer at temperature ~ 60°C. The volume rasio of carbon : matrix were fixed as 75:25% , 60:40% and 50:50% . the mixture materials were the dried in a oven at 60OC and successively pressed using a hot press compression apparatus at a pressure of 100, 150 and 200 bar and operating temperature heating of 175, 200 and 225°C respectively. The mechanical properties like tensile strength, flexural strength, compressive strength,hardness as well as the physical propertis like density, porosity, electric conductivity and internal structure were sistematicaly evaluated. Experimental results showed that heating at 225°C increased flexural strength at about 22 %. The highest electical conductivity was obtained in a bipolar plate with 75 : 25 volume ratio composition. However, the bipolar plate with 60 : 40 volume ratio which compressed under a pressure of 200 bar at 225°C was found to be the best result so far, having the closest properties with that utilized as bipolar plates in fuel cell applications.

Abstrak :
Material komposit merupakan gabungan dari dua material atau lebih menjadi satu sehingga memiliki sifat-sifat baru yang diinginkan. Sifat-sifat material komposit tersebut sangat dipengaruhi oleh proses manufakturnya. Vacuum infusion merupakan proses manufaktur material komposit modern yang dapat menggantikan metode konvensional. Pada penelitian ini, diperoleh desain peralatan vacuum infusion untuk proses manufaktur material komposit, dengan cetakan berupa kaca yang berukuran 1x1m, wadah resin berupa tabung PVC dengan volume 1L, resin trap berupa tabung kaca dengan volume 1L, dan pompa vakum dengan daya ½ HP serta vacuum speed 7 CFM. Untuk menguji peralatan ini, dilakukan studi pengaruh variasi jumlah lapisan bahan penguat terhadap waktu infusi resin. Luas dan jumlah lapisan bahan penguat divariasikan. Diperoleh waktu infusi resin untuk luas bahan penguat 15x20cm dari dua hingga enam lapis (dalam detik): 88, 115, 145, 174, dan 196; 15x25cm dari dua hingga enam lapis (dalam detik): 119, 142, 168, 198, dan 235; 15x35cm dari dua hingga enam lapis (dalam detik): 181, 203, 235, 263, dan 303. Selain itu diperoleh jumlah lapisan bahan penguat maksimum untuk luas bahan penguat 15x20cm, 15x25cm, dan 15x35cm yang dapat diakomodir masing-masing sebanyak 31 lapis, 29 lapis, dan 25 lapis. ......Composite material is a combination of two or more materials into one material that has the new desired properties. However, the manufacturing process influences the properties of the composite material made. Vacuum infusion is a modern composite material manufacturing process, which can replace conventional manufacturing process. In this study, the design of vacuum infusion equipment for composite materials manufacturing process are manufactured, and consists of: 1x1m glass as the mold, 1L PVC tube for the resin container, 1L glass tube for the resin trap, and ½ HP vacuum pump with 7 CFM vacuum speed. In order to tests this equipment, a study of the influence of reinforcement layers on the resin infusion time is done. The area and reinforcement layers are variated. The resin infusion time for 15x20cm reinforcement from two until six layers (in seconds): 88, 115, 145, 174, and 196; 15x25cm from two until six layers (in seconds): 119, 142, 168, 198, and 235; 15x35cm from two until six layers (in seconds): 181, 203, 235, 263, and 303. Also, the result for the number of maximum reinforcement layers for each 15x20cm, 15x25cm, and 15x35cm area are respectively 31 layers, 29 layers, and 25 layers.

Abstrak :
This book highlights the production of green composites from various sustainable raw materials. We now live in an environmentally conscious era, in which sustainable raw materials (renewable, biodegradable, recycled), sustainable processing sequences, the production of recyclable and biodegradable products, and avoiding the depletion of renewable resources are key considerations with regarding to producing any product. The textile sector is no exception. Accordingly, this book addresses these aspects in connection with textiles, and discusses how they can be actively practiced.

Abstrak :
This book highlights the processing, characterization and applications of various green composites. Composites are known for their unique properties, which are derived by combining two or more components. This yields properties such as greater strength and rigidity than that of the individual components, as well as reduced weight. To help achieve such outcomes, the book discusses the potential applications of hybrid bio-composites and sisal-fiber-reinforced epoxidized non-edible oil-based epoxy green composites.