scholarly journals Peningkatan Kuat Tarik Bioplastik dengan Filler Microfibrillated Cellulose dari Batang Sorgum

2020 ◽  
Vol 18 (2) ◽  
pp. 37
Author(s):  
Yuli Darni ◽  
Lia Lismeri ◽  
Muhammad Hanif ◽  
Sarkowi Sarkowi ◽  
Dita Synthauli Evaniya
Keyword(s):  
Tensile Strength ◽  
Mechanical Treatment ◽  
High Energy ◽  
Microfibrillated Cellulose ◽  
Weight Basis ◽  
Filler Concentration ◽  
Mechanical Method ◽  
High Energy Milling ◽  
Stirring Time ◽  
Disk Mill

Abstrak. Penelitian ini membahas tentang pengaruh rasio pati terhadap kitosan (dalam basis berat) dan konsentrasi microfibrillated cellulose sebagai filler dalam pembuatan bioplastik menggunakan pati sorgum, kitosan dan gliserol. Dalam penelitian ini, rasio pati terhadap kitosan yang divariasikan adalah 10:0, 9,5:0,5, 8,5:1,5, 7,5:2,5, 6,5:3,5, 5,5:4,5 (gr/gr). Microfibrillated cellulose sebagai filler disintesis dari batang sorgum dengan metode semimekanis. Perlakuan kimia diawali dengan delignifikasi batang sorgum dengan KOH 4% pada temperatur 80oC selama 1 jam untuk menghilangkan lignin. Setelah itu dicuci dan dipucatkan (bleaching) sebanyak dua kali menggunakan H2O2 6% pada suhu 70oC. Serbuk batang sorgum yang sudah kering dilanjutkan dengan perlakuan mekanis yaitu dimasukkan ke dalam disk mill  selama 90 menit dan dilanjutkan dengan high energy milling (HEM) untuk mengecilkan ukurannya sampai dengan rata-rata 4-8 µm. Filler ditambahkan, dan konsentrasinya (dalam basis berat) divariasikan dari 0, 1, 2, dan 3 %. Pati dan kitosan berukuran 63 mikron (lolos ayakan), waktu  pengadukan selama 35 menit pada kecepatan 375 rpm, dan penambahan 10% berat gliserol sebagai plasticizer dijaga konstan. Hasil terbaik pada penelitian ini diperoleh pada formulasi 8,5:1,5 (gr/gr). dan konsentrasi filler 3%. Produk bioplastik ini memiliki kuat tarik 11,64 MPa, persen perpanjangan 10,98%, modulus Young 105,96 MPa, densitas 0,915 gr/ml, dan penyerapan air  38,3%. Kata kunci: bioplastik, gliserol, kitosan, microfibrillated cellulose, sorgum. Abstract. The Improving of Bioplastic Tensile Strength with Microfibrillated Cellulose Filler from Sorghum Stem. This study discusses the effect of starch on chitosan ratio (in weight basis) and also the concentration of microfibrillated cellulose as a filler in the preparation of bioplastics using sorghum starch, chitosan, and glycerol. In this study, the ratio of starch to chitosan varied was 10:0, 9.5:0.5, 8.5:1.5, 7.5:2.5, 6.5:3.5, 5.5:4,5 (gr/gr). Microfibrillated cellulose as filler was encouraged from the sorghum stem by the semi-mechanical method. The delignification of sorghum stem initiated chemical treatment with a 4% KOH solution on 80oC for 1 hour to remove lignin. Bleaching is done after delignification using 6% H2O2 at 70oC. The dried sorghum powder is further followed by mechanical treatment that is put into disk mill for 90 minutes and continued with high energy milling (HEM) to reduce its size to an average of 4-8 µm. The filler is added, and the concentration (on a weight basis) varies from 0, 1, 2, and 3%. Starch and chitosan measuring 63 microns (sieve pass), stirring time for 35 minutes at a speed of 375 rpm, and the addition of 10% by weight of glycerol as a plasticizer is kept constant. The best results in this study were obtained in formulations 8.5:1.5 (gr/gr) and 3% filler concentration. This bioplastic product has 11.64 MPa tensile strength, 10.98% elongation, 105.96 MPa Young moduli, 0.915 gr/ml density, and 38.3% water uptake. Keywords: bioplastic, chitosan, glycerol, microfibrillated cellulose, sorghum.Graphical Abstract 

scholarly journals Effects of high mechanical treatment and long-term annealing on crystal structure and thermal stability of Ti2O3 nanocrystals

RSC Advances ◽  
2020 ◽  
Vol 10 (43) ◽  
pp. 25717-25720
Author(s):  
Albina A. Valeeva ◽  
Svetlana Z. Nazarova ◽  
Hartmuth Schröttner ◽  
Evgeny Yu. Gerasimov ◽  
Andrey A. Rempel
Keyword(s):  
Crystal Structure ◽  
Thermal Stability ◽  
Magnetic Susceptibility ◽  
Mechanical Treatment ◽  
High Energy ◽  
High Energy Milling ◽  
The Stability ◽  
Thermal Stability Of

The effect of high-energy milling and long-term annealing on the stability of Ti2O3 nanocrystals was studied using a magnetic susceptibility method.

scholarly journals Pengaruh Jumlah Siklum HEM (High Energy Milling) Pada Karakteristik MFC (Microfibrillated Cellulose) Dari Sekam Padi

2020 ◽  
Vol 21 (1) ◽  
pp. 29
Author(s):  
Anwar Maruf ◽  
Neni Damajanti
Keyword(s):  
Response Surface ◽  
High Energy ◽  
Microfibrillated Cellulose ◽  
High Energy Milling

MFC merupakan selulosa yang sudah mengalami proses lanjut yaitu refinerdan homogenizer sehingga ukurannya berskala nanometer (nm). Proses pembuatanMFC dapat dilakukan secara mekanik, yaitu dengan memanfaatkan refiner, highpressure homogenizer dan gelombang ultrasonic. Selain dengan metode mekanik,pembautan MFC juga dapat dilakukan dengan metode enzimatis. MFC dapatdigunakan sebagai komposit pada berbagai bidang seperti industri makanan, cat,kosmetik dan medis. Pemanfaatan selulosa sekam padi dalam pembuatan MFC belumbanyak dilakukan. Proses penting dalam pembuatan MFC sekam padi adalah prosesdelignifikasi untuk menghilangkan lignin dan silika, proses bleaching dan prosespenggilingan. Pada penelitian ini akan dikaji pengaruh konsentrasi hydrogenperoksida, temperature bleaching dan waktu penggilingan. Optimasi variabel dapatdilakukan dengan menggunakan Response Surface Metodology (RSM). Hasilpenelitian menunjukkan kondisi optimum untuk proses delignifikasi adalah padaperbandingan volume/berat sekam sebesar 9, konsentrasi H2O2 1,5% dan pH 11,5.Variabel yang signifikan terhadap kadar lignin adalah diketahui yang signifikanterhadap kadar lignin adalah pH (linier), rasio V/w (kuadratik), konsentrasi H2O2(kuadratik) dan pH (kuadratik). Proses HEM sangat berpengaruh pada karakteristikMFC. Semakin banyak siklus HEM, maka gugus aktif MFC akan semakin banyak.

INFLUENCE OF ACETONE AND METHANOL PROCESS CONTROL AGENTS IN THE SIZE AND MORPHOLOGY OF THE PARTICLES IN THE HIGH ENERGY MILLING OF THE NB-25%AL ALLOY

2019 ◽  
Author(s):  
Ágata Pontes ◽  
EDWIN MEDINA ◽  
Fabiano Sangi de Oliveira ◽  
Gilbert Silva ◽  
Marcos Cirilo ◽  
...  
Keyword(s):  
Process Control ◽  
High Energy ◽  
Al Alloy ◽  
High Energy Milling ◽  
Size And Morphology

Impact of the SiC addition on the morphological, structural and mechanical properties of Cu-SiC composite powders prepared by high energy milling

2021 ◽  
Author(s):  
Nailton T. Câmara ◽  
Rafael A. Raimundo ◽  
Cleber S. Lourenço ◽  
Luís M.F. Morais ◽  
David D.S. Silva ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Energy ◽  
Composite Powders ◽  
High Energy Milling

Effect of High-Energy Milling and Sintering Temperature on the Properties of Al2O3-WC-Co Composites

2021 ◽  
Author(s):  
Heytor V. S. B. Azevêdo ◽  
Rafael A. Raimundo ◽  
David D. S. Silva ◽  
Luís M. F. Morais ◽  
Franciné A. Costa ◽  
...  
Keyword(s):  
Sintering Temperature ◽  
High Energy ◽  
High Energy Milling

scholarly journals The Structure and Mechanical Properties of Hemp Fibers-Reinforced Poly(ε-Caprolactone) Composites Modified by Electron Beam Irradiation

2021 ◽  
Vol 11 (12) ◽  
pp. 5317
Author(s):  
Rafał Malinowski ◽  
Aneta Raszkowska-Kaczor ◽  
Krzysztof Moraczewski ◽  
Wojciech Głuszewski ◽  
Volodymyr Krasinskyi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Electron Beam ◽  
Impact Strength ◽  
Flexural Modulus ◽  
Natural Fibers ◽  
High Energy ◽  
Electron Radiation ◽  
Elongation At Break ◽  
Hemp Fibers

The need for the development of new biodegradable materials and modification of the properties the current ones possess has essentially increased in recent years. The aim of this study was the comparison of changes occurring in poly(ε-caprolactone) (PCL) due to its modification by high-energy electron beam derived from a linear electron accelerator, as well as the addition of natural fibers in the form of cut hemp fibers. Changes to the fibers structure in the obtained composites and the geometrical surface structure of sample fractures with the use of scanning electron microscopy were investigated. Moreover, the mechanical properties were examined, including tensile strength, elongation at break, flexural modulus and impact strength of the modified PCL. It was found that PCL, modified with hemp fibers and/or electron radiation, exhibited enhanced flexural modulus but the elongation at break and impact strength decreased. Depending on the electron radiation dose and the hemp fibers content, tensile strength decreased or increased. It was also found that hemp fibers caused greater changes to the mechanical properties of PCL than electron radiation. The prepared composites exhibited uniform distribution of the dispersed phase in the polymer matrix and adequate adhesion at the interface between the two components.

scholarly journals Three-dimensional thermomechanical converting of CTMP substrates: effect of bio-based strengthening agents and new mineral filling concept

Cellulose ◽  
2021 ◽  
Vol 28 (15) ◽  
pp. 9751-9768
Author(s):  
Teija Laukala ◽  
Sami-Seppo Ovaska ◽  
Ninja Kerttula ◽  
Kaj Backfolk
Keyword(s):  
Tensile Strength ◽  
Elastic Modulus ◽  
Three Dimensional ◽  
Microfibrillated Cellulose ◽  
New Mineral ◽  
Thermomechanical Pulp ◽  
Cationic Starch ◽  
Precipitated Calcium Carbonate ◽  
Filling Method ◽  
Positive Effect

AbstractThe effects of bio-based strengthening agents and mineral filling procedure on the 3D elongation of chemi-thermomechanical pulp (CTMP) handsheets with and without mineral (PCC) filling have been investigated. The 3D elongation was measured using a press-forming machine equipped with a special converting tool. The strength of the handsheets was altered using either cationic starch or microfibrillated cellulose. Precipitated calcium carbonate (PCC) was added to the furnish either as a slurry or by precipitation of nano-sized PCC onto and into the CTMP fibre. The 3D elongation of unfilled sheets was increased by the dry-strengthening agents, but no evidence on the theorised positive effect of mineral fill on 3D elongation was seen in either filling method. The performance of the strengthening agent depended on whether the PCC was as slurry or as a precipitated PCC-CTMP. The starch was more effective with PCC-CTMP than when the PCC was added directly as a slurry to the furnish, whereas the opposite was observed with microfibrillated cellulose. The 3D elongation correlated positively with the tensile strength, bursting strength, tensile stiffness, elastic modulus and bending stiffness, even when the sheet composition was varied, but neither the strengthening agent nor the method of PCC addition affected the 3D elongation beyond what was expectable based on the tensile strength of the sheets. Finally, mechanisms affecting the properties that correlated with the 3D elongation are discussed.

Fabrication of (Y2O3)n–ZnO nanocomposites by high-energy milling as potential photocatalysts

2021 ◽  
Author(s):  
A. Modwi ◽  
M. A. Ben Aissa ◽  
Kamal K. Taha ◽  
L. Khezami ◽  
J. El Ghoul ◽  
...  
Keyword(s):  
High Energy ◽  
High Energy Milling

Composite Ta–Cu powders prepared by high energy milling

2008 ◽  
Vol 26 (6) ◽  
pp. 499-503 ◽  
Author(s):  
F.A. Costa ◽  
A.G.P. Silva ◽  
J.F. Silva Júnior ◽  
U.U. Gomes
Keyword(s):  
High Energy ◽  
High Energy Milling

scholarly journals Sliding friction and wear performance of the nano-bioceramic α-Al2O3 prepared by high energy milling

2015 ◽  
Vol 91 ◽  
pp. 151-159 ◽  
Author(s):  
Mamoun Fellah ◽  
Mohammed Abdul Samad ◽  
Mohamed Labaiz ◽  
Omar Assala ◽  
Alain Iost
Keyword(s):  
Friction And Wear ◽  
Sliding Friction ◽  
High Energy ◽  
Wear Performance ◽  
High Energy Milling ◽  
Α Al2o3
Sign in / Sign up

Export Citation Format

Share Document