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"ABSTRAKPenelitian ini fokus pada peningkatan sifat mekanis Polipropilena impak kopolimer (PP) dengan menggunakan serat ijuk yang telah dimodifikasi. Modifikasi serat ijuk dilakukan dengan menggunakan proses alkalinisasi dan pemutihan. Proses tersebut bertujuan untuk meningkatkan kristalinitas dan kompatibilitas serat ijuk terhadap matriks PP. Pembuatan komposit PP-ijuk dilakukan menggunakan metode pencampuran lelehan panas untuk selanjutnya di cetak sesuai spesifikasi sampel uji sifat mekanis. Proses pencampuran dilakukan selama 15 menit dan dipelajari dua variabel utama, yakni variasi kadar serat ijuk (1%, 3%, 5%) dan variasi temperatur pencampuran (160⁰C dan 165⁰C). Komposit yang terbentuk selanjutnya dilakukan pengujian STA dan UTM. Dari hasil percobaan dapat disimpulkan bahwa peningkatan sifat mekanis yang optimal didapatkan pada percobaan menggunakan serat ijuk 1% dan suhu pencampuran 160⁰C. pada sampel tersebut teramati penambahan nilai kuat tarik hampir mencapai 1 Mpa. Hasil percobaan mengindikasikan bahwa serat ijuk hasil modifikasi dapat digunakan sebagai filler untuk meningkatkan sifat mekanis PP. Kondisi utama yang paling mempengaruhi peran positif serat ijuk adalah distribusi dan dispersi.

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ABSTRACTThis research focused on the employment of modificated ?ijuk? fibers as fillers to improve the mechanical properties of polypropylene impact copolymer (PP). Ijuk fibers are processed through alkali treatment and bleaching. Those processes are intended to improve the crystalinity and compatibility of ?ijuk? fibers to matrix PP. Afterwards, PP-ijuk composite is made by using rheomixing and subsequently casted in satisfactory to meet the requirements as standard sample for tensile strength testing. Rheomixing was conducted for 15 minutes in different concentration of ?ijuk? fibers (1%, 3%, 5%) and temperature (160⁰C dan 165⁰C). STA and UTM were used to observe the properties of the composite. From the results, can be concluded that the optimal condition to improve the mechanical properties of PP is obtained in the condition of 1% ?ijuk? fibers and 160⁰C mixing temperature. These condition were successfully improved the tensile strength of PP by 1 Mpa. The experiments indicated that modificated ?ijuk? fibers can be used as filler to increase the mechanical properties of PP. Distribution and dispertion were attributed as the main factors which influenced the processes."

"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.

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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 "

"[Pada penelitian ini, serat ijuk dihancurkan dan diayak ukuran 40 # setelah itu serat ijuk diberi perlakuan kimia dengan NaOH 2 % selama 1 jam, KMnO4 0,1 N selama 15 menit, dan NaClO 5 % selama 5 jam dengan tujuan mendapatkan selulosa kristalin. Setelah itu dilakukan proses pencampuran kering (hotmelt mixing) antara polipropilen dengan serat ijuk hasil perlakuan kimia dengan 7,5 % volum serat ijuk terhadap polipropilen dengan variabel temperatur 160°C, 165°C, dan 170°C dan variabel waktu pencampuran 15 menit dan 20 menit. Setelah itu dilakukan pengujian uji FTIR buat serat, sedangan buat komposit adalah uji tarik, uji STA, uji XRD, dan uji FE-SEM hal ini dilakukan untuk mendapatkan sifat kristalinitas dan mekanik dari komposit polipropilen ini. Hasil penelitian menunjukkan bahwa serat ijuk hasil perlakuaan lebih kristalin dari pada serat ijuk tanpa perlakukan, polipropilen dengan serat ijuk hasil perlakuaan kimia cukup kompatibel terhadap polipropilen, dari penelitian didapatkan sifat kristalinitas terbaik pada variabel 165°C selama 20 menit. Dan yang memiliki sifat kekuatan tarik paling baik adalah variabel 170°C selama 20 menit, sedangkan yang memiliki % elongasi paling baik adalah dengan variabel 160°C 20 menit.

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In this work, palm fiber crushed and sieved size 40 # after the palm fiber chemically treated with 2% NaOH for 1 hour, 0.1 N KMnO4 for 15 minutes, and 5% NaClO for 5 hours in order to obtain crystalline cellulose. Once that is done the dry mixing (hotmelt mixing) between polypropylene and palm fiber chemical treatment results with 7.5% volume of the palm fiber and polypropylene with a variable temperature of 160°C, 165°C and 170°C and a variable time mixing 15 minutes and 20 minutes. After it was examined FTIR test for fiber, while the composite is made tensile test, STA test, XRD test and FE-SEM test this is done to obtain crystallinity and mechanical properties of polypropylene composites this. The results show that fiber perlakuaan results more crystalline fibers than untreated palm fiber, polypropylene and palm fiber chemistry results treatment compatible enough to polypropylene, crystallinity of the research showed the best properties on the variable 165 ° C for 20 minutes. And who has the most excellent tensile strength properties are variable 170 ° C for 20 minutes, while the best of % elongation is at a variable 160 ° C 20 minutes.;In this work, palm fiber crushed and sieved size 40 # after the palm fiber chemically treated with 2% NaOH for 1 hour, 0.1 N KMnO4 for 15 minutes, and 5% NaClO for 5 hours in order to obtain crystalline cellulose. Once that is done the dry mixing (hotmelt mixing) between polypropylene and palm fiber chemical treatment results with 7.5% volume of the palm fiber and polypropylene with a variable temperature of 160°C, 165°C and 170°C and a variable time mixing 15 minutes and 20 minutes. After it was examined FTIR test for fiber, while the composite is made tensile test, STA test, XRD test and FE-SEM test this is done to obtain crystallinity and mechanical properties of polypropylene composites this. The results show that fiber perlakuaan results more crystalline fibers than untreated palm fiber, polypropylene and palm fiber chemistry results treatment compatible enough to polypropylene, crystallinity of the research showed the best properties on the variable 165 ° C for 20 minutes. And who has the most excellent tensile strength properties are variable 170 ° C for 20 minutes, while the best of % elongation is at a variable 160 ° C 20 minutes.;In this work, palm fiber crushed and sieved size 40 # after the palm fiber chemically treated with 2% NaOH for 1 hour, 0.1 N KMnO4 for 15 minutes, and 5% NaClO for 5 hours in order to obtain crystalline cellulose. Once that is done the dry mixing (hotmelt mixing) between polypropylene and palm fiber chemical treatment results with 7.5% volume of the palm fiber and polypropylene with a variable temperature of 160°C, 165°C and 170°C and a variable time mixing 15 minutes and 20 minutes. After it was examined FTIR test for fiber, while the composite is made tensile test, STA test, XRD test and FE-SEM test this is done to obtain crystallinity and mechanical properties of polypropylene composites this. The results show that fiber perlakuaan results more crystalline fibers than untreated palm fiber, polypropylene and palm fiber chemistry results treatment compatible enough to polypropylene, crystallinity of the research showed the best properties on the variable 165 ° C for 20 minutes. And who has the most excellent tensile strength properties are variable 170 ° C for 20 minutes, while the best of % elongation is at a variable 160 ° C 20 minutes.;In this work, palm fiber crushed and sieved size 40 # after the palm fiber chemically treated with 2% NaOH for 1 hour, 0.1 N KMnO4 for 15 minutes, and 5% NaClO for 5 hours in order to obtain crystalline cellulose. Once that is done the dry mixing (hotmelt mixing) between polypropylene and palm fiber chemical treatment results with 7.5% volume of the palm fiber and polypropylene with a variable temperature of 160°C, 165°C and 170°C and a variable time mixing 15 minutes and 20 minutes. After it was examined FTIR test for fiber, while the composite is made tensile test, STA test, XRD test and FE-SEM test this is done to obtain crystallinity and mechanical properties of polypropylene composites this. The results show that fiber perlakuaan results more crystalline fibers than untreated palm fiber, polypropylene and palm fiber chemistry results treatment compatible enough to polypropylene, crystallinity of the research showed the best properties on the variable 165 ° C for 20 minutes. And who has the most excellent tensile strength properties are variable 170 ° C for 20 minutes, while the best of % elongation is at a variable 160 ° C 20 minutes.;In this work, palm fiber crushed and sieved size 40 # after the palm fiber chemically treated with 2% NaOH for 1 hour, 0.1 N KMnO4 for 15 minutes, and 5% NaClO for 5 hours in order to obtain crystalline cellulose. Once that is done the dry mixing (hotmelt mixing) between polypropylene and palm fiber chemical treatment results with 7.5% volume of the palm fiber and polypropylene with a variable temperature of 160°C, 165°C and 170°C and a variable time mixing 15 minutes and 20 minutes. After it was examined FTIR test for fiber, while the composite is made tensile test, STA test, XRD test and FE-SEM test this is done to obtain crystallinity and mechanical properties of polypropylene composites this. The results show that fiber perlakuaan results more crystalline fibers than untreated palm fiber, polypropylene and palm fiber chemistry results treatment compatible enough to polypropylene, crystallinity of the research showed the best properties on the variable 165 ° C for 20 minutes. And who has the most excellent tensile strength properties are variable 170 ° C for 20 minutes, while the best of % elongation is at a variable 160 ° C 20 minutes., In this work, palm fiber crushed and sieved size 40 # after the palm fiber chemically treated with 2% NaOH for 1 hour, 0.1 N KMnO4 for 15 minutes, and 5% NaClO for 5 hours in order to obtain crystalline cellulose. Once that is done the dry mixing (hotmelt mixing) between polypropylene and palm fiber chemical treatment results with 7.5% volume of the palm fiber and polypropylene with a variable temperature of 160°C, 165°C and 170°C and a variable time mixing 15 minutes and 20 minutes. After it was examined FTIR test for fiber, while the composite is made tensile test, STA test, XRD test and FE-SEM test this is done to obtain crystallinity and mechanical properties of polypropylene composites this. The results show that fiber perlakuaan results more crystalline fibers than untreated palm fiber, polypropylene and palm fiber chemistry results treatment compatible enough to polypropylene, crystallinity of the research showed the best properties on the variable 165 ° C for 20 minutes. And who has the most excellent tensile strength properties are variable 170 ° C for 20 minutes, while the best of % elongation is at a variable 160 ° C 20 minutes.]"

"Polipropilena (PP) merupakan polimer termoplastik yang banyak digunakan. PP memiliki densitas yang rendah, mudah diproses, dapat didaur ulang, dan relatif murah, tetapi kekuatan tariknya rendah. Penggabungan PP dengan serat kenaf dapat meningkatkan sifat mekanik PP. Namun, PP dan serat kenaf memiliki kompatibilitas yang rendah. Oleh karena itu, serat kenaf diberi perlakuan pemutihan dengan NaClO 1% selama 2 jam pada temperatur ruang. Serat dikarakterisasi dengan FTIR, FESEM, dan uji tarik. Pemutihan menurunkan kandungan hemiselulosa, lignin, dan zat pengotor pada permukaan serat serta meningkatkan kekuatan tarik serat. Proses pencampuran PP dan serat kenaf dilakukan dengan metode hot melt mixing. Pencampuran dilakukan dengan komposisi serat 5% hingga 25% fraksi massa, temperatur 170oC hingga 190oC, dan waktu 10 menit hingga 20 menit. Komposit dikarakterisasi dengan FESEM, uji tarik, dan STA. Penambahan serat 5% fraksi massa menghasilkan komposit dengan kekuatan tarik, kristalinitas, dan kestabilan termal yang paling tinggi. Temperatur pencampuran 190oC menghasilkan komposit dengan kekuatan tarik, kristalinitas, dan kestabilan termal yang paling tinggi. Waktu pencampuran 20 menit menghasilkan komposit dengan kekuatan tarik paling tinggi.

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PP is a thermoplastic polymer which is widely used. PP has low density, easily processed, can be recycled, and relatively inexpensive, but has low tensile strength. Synthesis PP with kenaf fiber can improve the mechanical properties of PP. However, PP and kenaf fiber have low compatibility. Therefore, kenaf fiber treated by bleaching with NaClO 1% for 2 hours in room temperature. Fiber characterized by FTIR, FESEM, and tensile test. Bleaching reduces hemicellulose, lignin, and impurities on the fiber surface and increase the tensile strength of fiber. PP and kenaf fiber mixing is done by hot melt mixing method. Mixing is done with fiber composition of 5% to 25% mass fraction, temperature of 170oC to 190oC, and time of 10 minutes to 20 minutes. Composites characterized by FESEM, tensile test, and STA. The addition 5% mass fraction of fiber results a composite with the highest tensile strength, crystallinity, and thermal stability. Mixing temperature of 190oC results a composite with the highest tensile strength, crystallinity, and thermal stability. Mixing time of 20 minutes results a composite with the highest tensile strength."

"ABSTRAK Pada penelitian ini dibuat PMCs (Polymer Matrix Composites), menggunakan polipropilena (PP) sebagai matriks dan serat kenaf sebagai penguat. Polipropilena dan serat kenaf memiliki sifat permukaan yang berbeda, sehingga kompatibilitas antara keduanya buruk. Oleh karena itu, dilakukan modifikasi permukaan serat kenaf dengan metode alkalinisasi. Proses alkalinisasi dilakukan dengan merendam serat kenaf pada larutan NaOH 6% selama 8 jam. Selanjutnya pencampuran PP dan serat kenaf menggunakan metode hot melt mixing. Pengaruh komposisi serat, temperatur pencampuran, dan waktu pencampuran pada pembuatan komposit PP-kenaf dianalisa pada penelitian ini. Hasil pengujian menunjukan bahwa kekuatan tarik komposit PP-5%kenaf lebih baik dibanding kekuatan tarik PP. Namun, pada komposisi serat 15% fraksi massa mulai terjadi penurunan kekuatan tarik komposit. Hal ini disebabkan karena meningkatnya jumlah void dan fenomena fiber pull out seiring penambahan komposisi serat kenaf. Peningkatan komposisi serat juga menurunkan kristalinitas dan kestabilan termal pada komposit. Temperatur pencampuran divariasikan 170oC, 180oC, dan 190oC. Peningkatan temperatur pencampuran akan menghasilkan distribusi dan dispersi serat yang baik. Sehingga dengan temperatur pencampuran 190oC dihasilkan kekuatan tarik, kristalinitas, dan kestabilan termal optimal pada komposit. Waktu pencampuran divariasikan 10 menit, 15 menit dan 20 menit. Semakin lama proses pencampuran akan semakin optimal pula distribusi dan dispersi serat pada matriks, sehingga kekuatan tarik komposit makin meningkat.

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ABSTRACT In this research PMCs (Polymer Matrix Composites) was made, using polypropylene as matrix and kenaf fiber as reinforcement. PP and kenaf fiber have different surface properties, so that the compatibility between the two gets worse. Therefore, modification of kenaf fiber surface is carried out with alkaline treatment. The process of alkaline treatment is done by soaking the kenaf fiber in 6% NaOH solution for 8 hours. Then do the mixing process between PP and kenaf fiber using hot melt mixing method. The influence of fiber composition, temperature mixing, and time mixing on manufacture of composites were analyzed on this research. The test results showed that the tensile strength of PP-5%kenaf composite better than the tensile strength of PP. However, the composite with 15% fiber mass fraction decreased tensile strength. This was caused by the growing number of voids and fiber pull out phenomena over the addition of kenaf fiber composition. The increase of fiber composition also lowers the crystallinity and thermal stability on the PP-kenaf composite. Mixing temperature varied 170oC, 180oC, and 190oC. The increase of temperature mixing will produce good distribution and dispersion of fiber. So that on 190°C mixing temperature resulting composite with optimal tensile strength , crystallinity , and thermal stability. The mixing time varied for 10 minutes, 15 minutes, and 20 minutes. The longer the mixing process will resulting good dispersion and distribution, so that the composite tensile strength was increased."

"[Polipropilena (PP) kopolimer impak merupakan salah satu jenis PP yangcukup banyak digunakan. PP kopolimer impak dibuat dengan penambahan etilena yang mengakibatkan penurunan kristalinitas PP. Usaha yang dilakukan untuk memperbaiki sifat kristalinitas PP yaitu dengan menambahkan agen nukleasi. Pada penelitian ini PP ditambahkan agen nukleasi serat ijuk yang mendapatkan perlakuan alkali, dilanjutkan dengan oksidasi menggunakan katalis yang bertujuan untuk mempercepat waktu kristalisasi PP. Serat ijuk ditambahkan sebanyak 10% volum. Morfologi, kandungan kimia dan kristalinitas serat ijuk dikarakterisasi dengan menggunakan FESEM (Field Emission Scanning Electron Microscope), FTIR (Fourier Transmission Infra Red), XRD (X-Ray Diffraction). Terbukti bahwa telah terjadi perubahan diameter dan morfologi serat ijuk menjadi mikrofibril setelah perlakuan alkali yang dilanjutkan dengan oksidasi menggunakan katalis. Hal tersebut menunjukkan telah terjadi penggerusan permukaan serat ijuk yaitu dengan menurunnya kadar lignin dan hemiselulosa yang merupakan pengikat antara lignin dan selulosa. Hasil karakterisasi XRD menunjukkan kristalinitas serat ijuk yang tidak diberi perlakuan adalah 42% sedangkan yang mendapat perlakuan NaOH 2% selama 1 jam dilanjutkan oksidasi menggunakan NaClO 5% selama 5 jam dan katalis KMnO4 0,01 N selama 15 menit menunjukkan kristalinitas sebesar 60,75%. Untuk mengerahuiefek serat ijuk sebagai agen nukleasi dilakukan uji DSC (Differential Scanning Calorimetry) pada sampel campuran PP-serat ijuk. Hasil DSC menunjukkan ada perubahan kecepatan kristalisasi PP-serat ijuk yang menunjukkan efek serat ijuk sebagai agen nukleasi. Pada kecepatan pendinginan 10 ° C/menit, PP murni memiliki waktu kristalisasi 1,2 detik, PP-serat tanpa perlakuan memiliki waktu kristalisasi 1 detik sedangkan PP-serat ijuk dengan perlakuan NaOH 2% selama 1 jam dilanjutkan oksidasi menggunakan NaClO 5% selama 5 jam dan katalisKMnO4 0,01 N selama 15 menit memiliki waktu kristalisasi 0,9 detik.;Polypropylene (PP) copolymer impact is one type of PP is quite widely used. PP impact copolymer is made by adding ethylene which resulted in a decrease in crystallinity PP. Efforts are being made to improve the properties of PP crystallinity by adding a nucleating agent. In this study PP nucleating agent added “Ijuk” fibers that get alkali treatment, followed by oxidation using a catalyst which aims to accelerate the crystallization of PP time. “Ijuk” fibers was added as much as 10% volume. Morphology, chemistry and crystallinity of “Ijuk”fibers were characterized by using FESEM (Field Emission Scanning Electron Microscope), FTIR (Fourier Transmission Infra Red), XRD (X-Ray Diffraction). It was proved that there has been a change in fiber diameter and morphology of fibers into microfibrils after alkali treatment followed by oxidation using a catalyst. It showed that there has been annihilation of surface fibers with reduced levels of lignin and hemicellulose which is a binder between lignin and cellulose. XRD characterization result indicated the fiber crystallinity untreated fibers was 42% while with treatment 2% NaOH for 1 hour followed oxidation using NaClO 5% for 5 hours and the catalyst KMnO4 0.01 N for 15 minutes showed crystallinity of 60.75%. To determine “Ijuk” fiber as nucleating agents, the sample of PP-fiber mixture was tested by DSC (Differential Scanning Calorimetry). DSC results showed change in rate of crystallization of PP-fiber fibers that indicate the effects of “Ijuk” fiber as a nucleating agent. In the cooling rate of 10 ° C / min, pure PP has a crystallization time of 1.2 seconds, the PPfibers without treatment had a crystallization time of 1 second while the PP-fiber fibers with 2% NaOH treatment for 1 hour followed oxidation using NaClO 5% for 5 hour and 0.01 N KMnO4 catalyst for 15 minutes had a crystallization time of 0.9 seconds., Polypropylene (PP) copolymer impact is one type of PP is quite widelyused. PP impact copolymer is made by adding ethylene which resulted in adecrease in crystallinity PP. Efforts are being made to improve the properties ofPP crystallinity by adding a nucleating agent. In this study PP nucleating agentadded “Ijuk” fibers that get alkali treatment, followed by oxidation using acatalyst which aims to accelerate the crystallization of PP time. “Ijuk” fibers wasadded as much as 10% volume. Morphology, chemistry and crystallinity of “Ijuk”fibers were characterized by using FESEM (Field Emission Scanning ElectronMicroscope), FTIR (Fourier Transmission Infra Red), XRD (X-Ray Diffraction). Itwas proved that there has been a change in fiber diameter and morphology offibers into microfibrils after alkali treatment followed by oxidation using acatalyst. It showed that there has been annihilation of surface fibers with reducedlevels of lignin and hemicellulose which is a binder between lignin and cellulose.XRD characterization result indicated the fiber crystallinity untreated fibers was42% while with treatment 2% NaOH for 1 hour followed oxidation using NaClO5% for 5 hours and the catalyst KMnO4 0.01 N for 15 minutes showedcrystallinity of 60.75%. To determine “Ijuk” fiber as nucleating agents, thesample of PP-fiber mixture was tested by DSC (Differential ScanningCalorimetry). DSC results showed change in rate of crystallization of PP-fiberfibers that indicate the effects of “Ijuk” fiber as a nucleating agent. In the coolingrate of 10 ° C / min, pure PP has a crystallization time of 1.2 seconds, the PPfiberswithout treatment had a crystallization time of 1 second while the PP-fiberfibers with 2% NaOH treatment for 1 hour followed oxidation using NaClO 5%for 5 hour and 0.01 N KMnO4 catalyst for 15 minutes had a crystallization time of0.9 seconds.]"

"Beton sebagai material konstruksi dikenal getas (brittle) dan lemah terhadap tarik dibandingkan dengan material baja. Penelitian para ahli menunjukkan peningkatan daktilitas beton melalui penambahan serat pada material beton. Salah satu jenis serat yang sering digunakan adalah serat Polypropylene (PP), yang juga digunakan sebagai bahan dasar pembuatan gelas kemasan air mineral. Berangkat dari peningkatan jumlah limbah gelas plastik, maka penggunaannya sebagai material tambahan pada beton diharapkan dapat mengatasi permasalahan sampah perkotaan, dan dalam jangka panjang diharapkan dapat mengurangi biaya pembangunan rumah tinggal.Tujuan penelitian ini adalah untuk mempelajari efektifitas penggunaan cacahan limbah plastik PP terhadap peningkatan kuat tarik dan kuat lentur beton normal (fc' = 25 MPa). Kadar cacahan PP yang ditambahkan pada beton normal adalah 0,90; 1,35; 1,80; 2,25; 2,70; 4,50; 6,30; 9,00; 18,00 dan 27,00 kg/m3 atau dalam volume fraksi adalah 0,10; 0,15 0,20 ; 0,25; 0.30; 0,50; 0,70; 1,00; 2,00 dan 3,00% untuk pengujian kuat tarik yang dilakukan pada benda uji umur 7 dan 28 hari, serta 0,90; 1,35; 1,80; 2,25; 2,70; 4,50; 6,30; dan 9,00 kg/m3 atau dalam volume fraksi adalah 0,10; 0,15 0,20 ; 0,25; 0.30; 0,50; 0,70 dan 1,00% untuk pengujian kuat lentur yang dilakukan pada benda uji umur 28 hari.Percobaan pembebanan yang dilakukan meliputi pembebanan tarik belah, pembebanan lentur dan modulus elastisitas. Benda uji untuk pengujian tarikbelah dan modulus elastisitas adalah silinder dengan diameter 15 cm dan tinggi 30 cm, sedangkan benda uji percobaan pembebanan lentur adalah balok 10x10x55 cm3.Metode yang digunakan dalam penelitian ini adalah metode eksperimental, dimana percobaan dilakukan untuk mendapatkan kumpulan data, yang kemudian akan dianalisa secara statistik kuantitatif dan kualitatif.. Metode Analisis Rancang Campur yang digunakan adalah Metode US. Bureau. Benda Uji dibuat di Laboratorium Bahan Departemen Sipil FTUI. Standar Uji yang digunakan baik untuk pengujian material dasar, beton muda dan beton yang sudah mengerasmengacu pada Standar ASTM.Penambahan jumlah cacahan plastik polypropylene pada kadar tertentu akan menurunkan workabilitas dari beton, hal ini ditunjukkan dengan penurunan slump beton seiring dengan peningkatan kadar cacahan.Dari Hasil Pengujian didapat, penambahan cacahan plastik polypropylene secara umum tidak memiliki pengaruh yang berarti pada tegangan tarik beton normal. Peningkatan paling besar terjadi pada benda uji kadar 0,3% umur 7 hari, yaitu sebesar 10,989%; dengan tegangan tarik berkisar antara 0,456 - 0,648 √ ? ' c. Hal ini secara umum diakibatkan karena ikatan atau gaya adhesi antara cacahan dengan matriks beton lebih lemah dari gaya kohesi antara matriks beton itu sendiri. Hal ini dibuktikan dengan uji tarik belah, dimana cacahan plastik pada benda uji yang terbelah tidak putus akibat pembebanan, melainkan masih tersambung, sedangkan material.Sedangkan Penambahan cacahan plastik polypropylene secara umum meningkatkan tegangan tarik lentur beton normal. Peningkatan paling besar terjadi pada benda uji kadar 0,7% umur 28 hari, yaitu sebesar 17,098%; dengan tegangan tarik lentur berkisar antara 0,853 - 1,056 √ ? & c.

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Concrete as construction material is known brittle and possess relatively weak tensile strength, compared to steel material. Experiments done by the experts shows an improvement in ductility of concrete by adding fiber to concrete material. One of the fibers that often used is Polypropylene (PP) fiber, which also used as a raw material in mineral water plastic glass manufacture. The increase ofamount of plastic glass waste, gives an idea to use it as an addition material in concrete. It expects decrease the urban waste problem, and in long term, to reduce the cost to build a house.The purpose of this experiment is to study the effect of usage of PP plastic waste in tensile and flexural strength of normal concrete with fc? 25 MPa. The amount of crushed PP added to normal concrete are 0,90; 1,35; 1,80; 2,25; 2,70; 4,50; 6,30; 9,00; 18,00 and 27,00 kg/m3 or in fraction volume are 0,10; 0,15 0,20 ; 0,25; 0.30; 0,50; 0,70; 1,00; 2,00 and 3,00% for tensile strentgh test which done in age 7 and 28 days, also 0,90; 1,35; 1,80; 2,25; 2,70; 4,50; 6,30; and 9,00 kg/m3 or in fraction volume are 0,10; 0,15 0,20 ; 0,25; 0.30; 0,50; 0,70 and 1,00% for flexural strentgh test which done in age 28 days.The test is consist of splitting tensile test, flexural test and modulus elasticity test. The sample for tensile and modulus elasticity test is cylinder with 15 cm diameter and 30 cm height, as for the flexural test is beam with size 10x10x55 cm3.In this experiment the experimental method will be used, where the experiment done to collect data, and the data will be analyzed quantitative and qualitative statistically. The Mix Design Method used is US. Bureau Method. The sample will be made in Material Laboratory, Civil Engineering Department, Faculty of Engineering, University of Indonesia. The Standard to test the constituent materials, fresh concrete and hard concrete is based on ASTM Method.The addition of crushed polypropylene plastic in specific amount will decrease the workability of concrete, shown by the decrease of concrete?s slump as the increase of crushed plastic amount.The Test shows that the addition of crushed polypropylene plastic will not influence the tensile stress of normal concrete, generally. The highest increase happened in volume fraction 0.3% age 7 days, with 10.989%; and the tensile strengths have range from 0.456 - 0.648 √ ? & c. . This is generally because the bond or adhesion between the plastic and matrix is weaker then the cohesion of the matrix itself. It is proved by the splitting tensile test, where the plastics are do not yield by the loading, as for the aggregates are crushed by the loading.As for the flexural tensile stress, it tends to increase. The highest increase, happened in volume fraction 0.7% age 28 days, with 17.098%; and the flexural strengths have range from 0.853 - 1.056 √ ? & c."

"Pada zaman sekarang ini dimana penggunaan energi yang murah, efisien, dan ramah lingkungan sangat diperlukan, maka dikembangkan sel tunam (fuel cells) sebagai sumber energi baru. Kekurangan dari sel tunam konvensional adalah massanya yang berat dan proses manufaktur yang sulit sehingga harga sel tunam itu sendiri menjadi mahal. Sifat ini merupakan kontribusi dari pelat bipolar pada sel tunam tersebut. Oleh karena itu, dibutuhkan pelat bipolar yang ringan, mudah diproses, dan murah. Dalam penelitian ini dikembangkan komposit pelat bipolar menggunakan matriks polipropilena (PP), penguat karbon, dan aditif polyvinylidene fluoride (PVDF) yang divariasikan komposisinya untuk mendapatkan sifat konduktivitas dan mekanis yang baik.Sifat-sifat dari komposit yang dihasilkan diuji dengan pengujian mekanis, konduktivitas, dan melt flow indexer. Selain itu, dilakukan juga pengamatan mikrograf dengan menggunakan SEM.Dari hasil pengujian tersebut, didapatkan bahwa sifat mekanis akan semakin menurun seiring dengan penambahan penguat karbon dalam komposit. Namun, nilai konduktitasnya kecil. Dari keempat formula, didapatkan bahwa nilai mekanis yang paling baik terdapat pada formula dua dengan persentase penguat karbon sebesar 44 % wt. dan sifat konduktivitas terbaik terdapat pada formula tiga dengan 80 % wt. karbon dimana di dalamnya terkandung 25 % wt. grafit.Dalam penelitian ini belum didapatkan komposisi yang optimal dalam pembagian komposisi PP dan penguat karbon. Selain itu, nilai konduktivitas juga masih kecil karena PVDF tidak dapat membantu ikatan PP dengan penguat karbon dengan baik.

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Nowadays, when the usage of cheap, efficient, and eco-friendly energy is needed, fuel cells as a new energy source is developed. The disadvantage of conventional fuel cells are its heavyness and its low processability, which leads to its high price. These properties are affected by its bipolar plates. Therefore, we need a lightweight, easy-to-process, and cheap bipolar plates.In this study, we develop a bipolar plate composite by using polypropylene matrix, carbon reinforcements, and polyvinylidene fluoride as an additive and varying its composition to develop good conductivity and mechanical properties.Composite properties are evaluated by using mechanical tests, conductivity tests, and melt flow indexer. SEM micrography is also used.From the results, we can conclude that mechanical properties will decrease as the adding of carbon reinforcements in the composite. But, it will decrease its conductivity. From 4 formulas we develop, second formula had the best mechanical properties with 44 % wt. carbon reinforcement and the third formula had the best conductivity properties with 80 % wt. carbon reinforcements, whereas, it has 25 % wt. graphite.In this study, the optimal composition hasn?t been retrieved. The conductivity result also shows low conductivity because PVDF doesn?t help the bonding between PP and carbon reinforcements perfectly."