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"Pengurangan hambatan xanthan gum dalam larutan air telah dipelajari sebagai fungsi konsentrasi dengan menggunakan pipa acrylic. Percobaan dilakukan dengan mengukur pressure drop. Tujuan penelitian untuk menyelidiki pengurangan gesekan dalam pipa acrylic dengan penambahan xanthan gum dalam larutan air. Pipa acrylic dengan diameter 16 mm digunakan dalam penelitian ini dengan variasi konsentrasi larutan xanthan gum 150 ppm, 300 ppm dan 400 ppm. Percobaan dilakukan dari bilangan Reynolds rendah hingga tertinggi 45.155. Penulis mengamati rasio penurunan hambatan maksimum yaitu 46,42% pada bilangan Reynolds 13.000 pada pipa acrylic diameter dalam 16 mm dengan larutan xanthan gum konsentrasi 400 ppm. Penurunan koefisien gesek mengindikasikan keefektifan fluida uji sebagai drag reduction agent yang dapat dilihat dari koefisien gesek terhadap garis grafik Blasius.

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The drag reduction of xanthan gum in aqueous solutions of was studied as a function of concentration with acrylic pipes apparatus. Experiments were carried out by measuring the pressure drop. The purpose of this research is to investigate the reduction of pressure drop in a acrylic pipe with the addition fiber in aqueous solution. Circular pipe with diameter of 16 mm are used in this study. Concentration of xanthan gum solutions are 150 ppm, 300 ppm and 400 ppm.

Experimental was conducted from low to high Reynolds number up to 45.155. We observed a maximum drag reduction ratio of 46,42 % at Reynolds number about 13.000 with xanthan gum solutions concentration of 400 ppm. The pressure drop measurements indicate the effectiveness of xanthan gum as drag reduction agent which can be seen of drag coefficient curve compare to Blasius curve."

"Hidrogel kitosan-graft-poli(N-vinil kaprolaktam) disintesis dengan metode polimerisasi radikal bebas dengan larutan yang diikat silangkan. Agen pengikat silang etilen glikol dimetakrilat (EGDMA) dan N,N’-metilen bisakrilamida (MBA) digunakan untuk menentukan pengaruh dari jenis dan konsentrasi pengikat silang pada rasio swelling saat setimbang. Spektrum Fourier Transform Infra Red Spectroscopy (FTIR) dan Differential Scanning Calorimetry (DSC) membuktikan terbentuknya polimer graft yang terikat silang. Hasil menunjukkan semakin tinggi konsentrasi pengikat silang, semakin besar rasio swelling yang dihasilkan. Ditemukan bahwa MBA merupakan agen pengikat silang yang lebih efektif dari EGDMA dengan nilai rasio swelling 46,70% pada MBA 2% pada waktu optimal yang diperoleh yaitu tiga jam.

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Chitosan-graft-poly(N-vinyl caprolactam) Hydrogels were synthesized by free radical crosslinking polymerization with solvent. Ethylene glycol dimethacrylate (EGDMA) and N,N’-methylene bisacrylamide (MBA) crosslinking agent were employed to determine the effect of crosslinker type and concentration in equilibrium swelling rate (ESV). Fourier Transform Infra Red Specstrocopy (FTIR) spectrum confirm the formation of crosslinking graft polymer. Result showed that higher concentration of crosslinker, the swelling rate produced was increase. It was found that MBA more effective than EGDMA with swelling rate up to 46,70% at 2% MBA with optimum reaction time is three hours."

"Smart polymers are polymers that respond to different stimuli or changes in the environment. Smart Polymers and their Applications reviews the types, synthesis, properties, and applications of smart polymers.Chapters in part one focus on types of polymers, including temperature-, pH-, photo-, and enzyme-responsive polymers. Shape memory polymers, smart polymer hydrogels, and self-healing polymer systems are also explored. Part two highlights applications of smart polymers, including smart instructive polymer substrates for tissue engineering; smart polymer nanocarriers for drug delivery; the use of smart polymers in medical devices for minimally invasive surgery, diagnosis, and other applications; and smart polymers for bioseparation and other biotechnology applications. Further chapters discuss the use of smart polymers for textile and packaging applications, and for optical data storage."

"Polymer blends offer properties not easily obtained through the use of a single polymer, including the ability to withstand high temperatures. High temperature polymer blends outlines the characteristics, developments, and use of high temperature polymer blends.The first chapter introduces high temperature polymer blends, their general principles, and thermodynamics. Further chapters go on to deal with the characterization of high temperature polymer blends for specific uses, such as fuel cells and aerospace applications. The book discusses different types of high temperature polymer blends, including liquid crystal polymers, polysulfones, and polybenzimidazole polymer blends and their commercial applications.High temperature polymer blends provides a key reference for material scientists, polymer scientists, chemists, and plastic engineers, as well as academics in these fields."

"Salah satu metoda untuk menentukan keberadaan fosfat di lingkungan perairan adalah dengan pembuatan adsorben selektif Ion Imprinted Polymer menggunakan kitosan termodifikasi. Kitosan suksinat, fosfat, MBA (Metilen Bis Akrilamida) digunakan sebagai monomer, cetakan dan agen pengikat silang. Awalnya kitosan dimodifikasi membentuk kitosan suksinat dan ditambahkan ion besi, Fe(III) membentuk kompleks Fe(III) kitosan suksinat. Kemudian kompleks Fe(III) kitosan suksinat ditambahkan fosfat dan selanjutnya fosfat dikeluarkan dengan KOH sehingga membentuk rongga selektif untuk ion fosfat. Setelah rongga terbentuk, kompleks Fe(III) kitosan suksinat diikat silang dengan menggunakan MBA. Penyerapan fosfat dengan polimer yang telah dicetak dengan fosfat lebih tinggi bila dibandingkan dengan polimer tanpa dicetak dan kitosan. Penyerapan ion fosfat maksimum pada ion imprinted polymer dicapai saat 30 menit dengan kapasitas adsorpsi (Q) = 4,382.59 mg/g, pH 3 dengan Q = 4,806.74 mg/g dan konsentrasi 3-4 ppm dengan Q = 2,884.62-3,703.70 mg/g. Penyerapan fosfat pada ion imprinted polymer terganggu dengan adanya ion bikarbonat dengan Q = 1,205.27 mg/g sedangkan Q untuk penyerapan fosfat tanpa adanya gangguan ion (kontrol) sebesar 6,812.37 mg/g. Penyerapan Sodium Tripolifosfat (STPP) lebih kecil pada polimer yang dicetak dengan fosfat. Q untuk penyerapan STPP 2 ppm sebesar 1,670.35 mg/g sedangkan Q pada penyerapan fosfat 2 ppm sebesar 1,909.76 mg/g.

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One method for determining the presence of phosphate within the waters was by making selective adsorbent ion imprinted polymer using modified chitosan. Chitosan succinate, phosphate, MBA (Methylene Bis Acrylamide) were used as a monomer, mold and crosslinking agent. Firstly, chitosan was modified to form chitosan succinate and added iron ions (III) to form complexes of Fe(III) chitosan succinate. Then the complex Fe(III) chitosan succinate was added with phosphate and then phosphate further removed with KOH to form a cavity for the adsorption phosphate ion selectively. Once the cavity was formed, the complex Fe(III) chitosan succinate was then crosslinked using MBA. Phosphate adsorption with polymers that have been imprinted with phosphate was higher when compared with non-imprinted polymer and chitosan. Maximum adsorption of phosphate ions on imprinted polymer was achieved after 30 minutes contact time with adsorption capacity (Q) 4,382.59 mg/g, pH 3 with Q = 4,806.74 mg/g and the concentration of 3-4 ppm with Q = 2,884.62-3,703.70 mg/g. The adsorption of phosphate on the imprinted polymer in the presence of bicarbonate ions as interference was by Q = 1,205.27 mg/g, whereas Q for the adsorption of phosphate ions in the absence of interference was (control) of 6,812.37 mg/g. Adsorption of Sodium tripolyphosphate (STPP) is smaller in the polymer imprinted with phosphate. Q for the absorption of 2 ppm STPP standar was 1,670.35 mg / g, while Q at 2 ppm of phosphate adsorption was 1,909.76 mg / g."

"This book presents a thorough discussion of the physics, biology, chemistry and medicinal science behind a new and important area of materials science and engineering: polymer nanocomposites. The tremendous opportunities of polymer nanocomposites in the biomedical field arise from their multitude of applications and their ability to satisfy the vastly different functional requirements for each of these applications. In the biomedical field, a polymer nanocomposite system must meet certain design and functional criteria, including biocompatibility, biodegradability, mechanical properties, and, in some cases, aesthetic demands. "