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"Penelitian mengenai nanokomposit polimer telah menjadi penelitian yang banyak dilakukan dalam ilmu kimia polimer dan material selama belakangan ini. Telah berhasil dilakukan fabrikasi nanokomposit dengan matriks polipropilen dan lempung Pacitan sebagai nanofiller dengan menggunakan metode melt intercalation. Campuran terdiri dari polipropilen (PP), organoclay dari Pacitan (OCP), maleicanhydride (MA) dan diphenylamine (DPA). Struktur nanokomposit dikarakterisasi menggunakan X-ray diffractometer (XRD) dan transmission electron microscopy (TEM). Hasilnya menunjukkan terjadinya interkalasi clay Pacitan yang menyebabkan pelebaran jarak galeri lapisan silikat. Uji mekanik menunjukkan nanokomposit memiliki modulus tarik dan lentur lebih tinggi, tapi kekuatan tarik dan lentur lebih rendah dibandingkan PP-OCP0 dan harga literatur PP murni. Modulus tarik yang paling tinggi dimiliki oleh nanokomposit dengan kandungan organoclay sebanyak 7 wt%. Sifat termal PP-OCP0 dan PP-OCP7 diuji menggunakan alat Heat deflection temperature (HDT). Hasilnya menujukkan bahwa nilai HDT PP-OCP7 lebih rendah dari nilai HDT PP-OCP0.

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The study of polymer nanocomposites has been an active research field in polymer chemistry and materials science for the past decade. Nanocomposites which consist of polypropylene as matrix and Pacitan clay nanofiller have been successfully prepared by a melt intercalation method. The compound consisted of polypropylene (PP), Pacitan organoclay (OCP), maleicanhydride (MA), and diphenylamine (DPA). The structure of nanocomposites was investigated using an X-ray diffractometer (XRD) and transmission electron microscopy (TEM). The results show that an intercalation of silicate layers was occurred. The intercalation caused the silicate layer distance expansed and PP was able to move into the gallery. The results of mechanical test show that the nanocomposites have higher tensile and flexural moduli, but lower tensile and flexural strengths compared to PP-OCP0 and theoretical value of pristine PP. The PP-OCP7 sample has best mechanical properties. Sample of PP-OCP0 and PP-OCP7 were thermal tested by using a heat deflection temperature (HDT) machine. The HDT results show that PP-OCP7 has a lower HDT value than the PP-OCP0."

"Polypropylene (PP) adalah termoplastik yang sangat luas pemakaiannya. Kombinasi antara permintaan yang tinggi dan kemudahan daur ulang menyebabkan aplikasi PP daur ulang menjadi hal yang sangat biasa dan diterima secara umum. Dalam penelitian ini, penulis membandingkan struktur dan sifat mekanik PP murni, PP daur ulang dan PP daur ulang komersial yang dipakai sebagai gantungan pakaian. Pengujian termal dengan DSC menunjukkan bahwa daur ulang tidak menyebabkan perubahan titik leleh yang signifikan, yaitu tetap berada pada kisaran 160 oC - 163°C. Identifikasi bahan dengan FTIR menunjukkan bahwa PP daur ulang komersial mengandung campuran unsur Polyethylene (PE) yang tidak terdapat pada PP murni dan PP daur ulang. Hasil uji tarik dan uji kekerasan tidak menunjukkan perubahan yang signifikan antara PP murni dan PP daur ulang. Di sisi lain, uji tarik menunjukkan bahwa kuat tarik PP daur ulang komersial lebih rendah 22,1% daripada PP murni, modulus Young turun 8,1%, dan strain-at-break berkurang secara drastis sebesar 65,7%. Uji kekerasan dengan Shore Hardness menunjukkan bahwa kekerasan relatif tidak berubah karena daur ulang. Hal ini didukung dengan SEM yang memperlihatkan citra PP daur ulang komersial memiliki permukaan yang relatif lebih datar dengan ukuran butir lebih kecil daripada PP murni, yang menunjukkan bahwa bahan bersifat lebih brittle.

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Polypropylene (PP) is a type of thermoplastic that is widely used in our daily activities. A combination of high demand and easinest recycling maker the recycled PP has been generally accepted. In this study, a study of the structure and mechanical characteristics of original PP, recycled PP, and commercial recycled PP is compared, especially the ones that is applied as cloth hanger. DSC thermal tests showed that the recycling process did not cause a significant change to the material?s melting point, which stays in the range of 160 oC - 163°C.

Meanwhile, FTIR tests showed that the commercially recycled PP contains of Polyethylene (PE), which element was not found in original PP and recycled PP. On the other side, tensile test showed that the tensile strength, Young modulus and strain-at-break are lower than those of original PP by 22,1 % ; 8,1 % and 65,7 % respectively. Tensile and hardness test demonstrated there is no significant differences between original PP and recycled PP. Furthermore, Shore Hardness tests show the recycling process has a little effect on the material?s hardness. These fact is also supported by morphological observation using SEM that the surface contour of the images of commercial recycled PP is relatively more flat and has smaller grain size than those of original PP, which indicates that the commercial recycled PP is relatively more brittle."

"Pada penelitian ini telah dikembangkan komposit berbasis polimer polipropilena (PP) dengan penguat serat alam yaitu serat sisal dan serat sabut kelapa. Bentuk morfologi serat alam divariasikan dalam bentuk bulk (chopped) dan berbentuk single of fiber melalui proses pulping. Jenis polimer yang digunakan adalah homopolimer dan kopolimer. Komposit yang dihasilkan dikarakterisasi untuk memperoleh komposit dengan kekuatan optimum tanpa mengesampingkan nilai ketangguhan-nya. Perlakuan panas dilakukan terhadap komposit serat alam pada suhu 70°, 100° dan 130°C selama 20 jam.Dari penelitian ini diketahui bahwa sifak mekanis polimer PP dapat ditingkatkan dengan penambahan serat alam. Serat sisal memiliki sifat mekanis yang lebih baik jika dibandingkan dengan serat sabut kelapa, hal ini dibuktikan dengan nilai kuat tarik, struktur mikro, derajat kristalinitas dan stabilitas terhadap panas. Dari analisa FE-SEM, perubahan bentuk serat menjadi pulp dapat meningkatkan dispersi serat dalam matrik polimer, namun hal ini hanya meningkatkan kuat tarik dan kuat tekuk. Nilai kuat tarik, kuat tekuk, modulus dan impak komposit pada penelitian ini dapat ditingkatkan dengan tetap mempertahankan bentuk morfologi bulk (chopped) dari serat alam dengan penambahan EPDM 2.5% berat dan perlakuan panas pada 130°C. Mekanisme peningkatan ketangguhan komposit disebabkan oleh pembentukan kristal β-phase PP serta mekanisme fiber pull out dari serat alam bentuk chopped pada matrik polimer. Polimer homopolimer memberikan performa komposit yang lebih baik jika dibandingkan dengan kopolimer.

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The aim of this study is to develop polypropylene (PP) composite reinforced with sisal and coconut fibers. The effect of fiber morphology in term of bundles (chopped) and single of fibers (pulp), as well as types of polymer (homopolymer and copolymer) were manufactured to obtain high strength and high toughness composites. Composites were annealed at 70°, 100° and 130°C.

From this study, it is reported that sisal fiber is superior to coconut fibers as reinforcing agents. It is not necessary to convert the bundles into pulp. Optimum composite could be obtained by annealed the composites of 40% weight sisal chopped reinforced PP at 130°C by addition of EPDM 2.5% wt in the presence of PP-g-MA 5% wt. The formation of β-phase crystallization of PP revealed from XRD analysis and fiber pull out mechanism take responsible for the improvement of the high toughness of composite. Homopolymer gave best performance as matrix compared to copolymer for strength and toughness composites."

"[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.]"

"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."

"Penelitian ini menyajikan model tegangan dan regangan dalam tekan pada spesimen beton terkekang dan tidak terkekang di dalam tekan yang menggunakan plastik Polypropilene sebagai pengganti agregat kasar. Hasil test tekan pada berbagai spesimen kolom pendek akan dikaji dan di analisa pada karakteristik tegangan-regangan, efek dari penulangan kekangan, dan peningkatan kemampuan gaya tekannya. Berdasarkan hasil test, tulangan kekang meningkatkan kuat tekan, serta daktilitas penampang. Identifikasi parametrik terhadap berbagai persamaan umum dari beton normal yang sudah ada digunakan terhadap hasil eksperimen untuk mendapatkan nilai parameter baru koefisien kekangan  k1 dan k2 yang sesuai untuk beton ringan. Diagram tegangan-regangan untuk spesimen beton ringan kolom lingkaran dan persegi dari hasil eksperimen dibandingkan dengan diagram tegangan-regangan untuk beton normal yang umum dipakai, hasilnya menunjukkan kesesuaian yang baik.

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Plastic production in the world ramped up to 322 million tons annual in 2015 with growth rate of 8.4% annually resulting large amount of plastic waste in nature. These plastic wastes are almost non-degradable in nature and polluting the environment in land and the sea. The use of recycled plastic aggregate for coarse aggregate in concrete is part of efforts to reduce environmental pollution by processing plastic grain in to coarse aggregate to substitute nature aggregate for light concrete. This study presents the analysis of concrete stress and strain model under compression of unconfined and confined concrete using Polypropilene plastic as substitution for coarse aggregate. To improve bonding between plastic aggregate and cement paste, this plastic aggregate is then coated with sands by placing and mixing the plastic aggregate with sands into a heater rotating cylinder. Test results of various specimens of short column will be reviewed and analysed in the stress and strain characteristics, effect of steel confinement, and performance improvement in compression. Based on experiment results, steel confinement increases compressive strength and ductility of the section. Parametric identification on established stress-strain model for normal concrete is used on the experimental results to obtain the new parameter values for confinement coefficient k1 and k2 that are suitable for this lightweight concrete. The stress-strain diagram for lightweight concrete of cylinder and square column specimen as resulted from experiment compared to the established stress-strain diagram used for normal concrete, the result indicates good agreement."