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1

Minimizing the explosion enthalpy of ammonium nitratewith polyethylene glycol and carboxymethyl celluloseto prevent terrorist attacks

Ozan-Gezerma Ahmet

Chemical and Process Engineering

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2020

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Vol. 41, nr 3

183-–195

EN

The use of ammonium nitrate due to its high nitrogen content (>26%) has made it the most utilizedfertilizer in agricultural areas. However, being easily accessible with this feature encouraged its use fordifferent purposes. Ammonium nitrate is usually produced with large tonnage (>50ton/h) and highcost (>$20million) production processes. Therefore, any changes that can be made in the processmust be applied in the process so that the result can be achieved easily without increasing the costin any way. In this study, it is aimed to reduce the explosion sensitivity of ammonium nitrate usedfor explosive purposes in terrorist attacks. Thus, it was aimed to solve the problem by adding variouschemicals to the ammonium nitrate production process so that it can only be used for agriculturalpurposes. For this purpose, the production process was examined by adding carboxymethyl celluloseand polyethylene glycol to the ammonium nitrate production process and the accuracy of the resultswas tested by instrumental analysis methods

2

Structural Studies (FTIR, XRD) of Sodium Carboxymethyl Cellulose Modified Bentonite

Cukrowicz S., Grabowski B., Kaczmarska K., Bobrowski A., Sitarz M., Tyliszczak B.

Archives of Foundry Engineering

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2020

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Vol. 20, iss. 3

119--125

EN

The study investigates the effect of the organic compound representing the cellulose derivative - sodium salt of carboxymethyl cellulose (CMC/Na) on the structure of the main component of bentonite (B) - montmorillonite (MMT). Structural analysis revealed that the CMC/Na of different viscosity interacts with the mineral only via surface adsorption, causing at the same time partial or full delamination of its layered structure. This was confirmed by the XRD diffraction tests. Such polymer destructive influence on the structure of the modified main component of the bentonite limits the use of its composites as an independent binder in moulding sand technology, but does not exclude it from acting as an additive being a lustrous carbon carrier. According to the IR spectra of the B/CMC/Na materials, it can be stated that the interaction between the organic and inorganic parts is based on the formation of hydrogen bonds. That kind of the interpretation applies especially to the MMT modified in the bentonite with a lower viscosity polymer. The characteristics of the main IR absorption bands for composites with a higher viscosity polymer indicates the formation of less stable structures suggesting the random nature of the hydrogen bonds formation.

3

Fe2+ removal from water using PVDF membranes, modified with magnetite nanoparticles, by polyelectrolyte enhanced ultrafiltration

Konovalova V., Kolesnyk I., Ivanenko O., Burban A.

Inżynieria i Ochrona Środowiska

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2018

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T. 21, nr 1

39--49

EN

The aim of this study was to show results of Fe2+ removal from water by polyelectrolyte enhanced ultrafiltration on polyvinylidene fluoride membranes modified with magnetite nanoparticles. Magnetite nanoparticles were synthesized by the co-precipitation method and stabilized with sodium polyacrylate. At first stage, the surface of PVDF membranes was modified by grafting of polyethylenimine. At the second stage the polyelectrolyte, grafted to the membrane surface, was used as a linker for magnetite nanoparticles immobilization. The modification of membranes was confirmed by IR spectroscopy, scanning electron microscopy and electro kinetic analysis. The dependence of zeta-potential on pH for PVDF membrane modified with PEI has confirmed the modification of the membrane surface as zeta-potential increases with pH decrease. SEM has shown that the surface of modified membrane is densely covered with nanoparticles, which form clusters. The dependence of the volumetric flux on the applied pressure at various concentrations of the carboxymethylcellulose (CMC) has been studied. Polyelectrolyte enhanced ultrafiltration with CMC has been used for iron(II) removal at initial Fe2+ concentration of 20 mg/L. The concentrations of iron(II) in permeate using an unmodified membrane has ranged from 0.6 to 1.0 mg/L, whereas for the modified membrane it has been 0.02÷0.08 mg/L.

PL

Celem pracy było przedstawienie wyników badań dotyczących usuwania Fe2+ z wody za pomocą ultrafiltracji wspomaganej polielektrolitem na membranach z fluorku poliwinylidenu modyfikowanych nanocząstkami magnetytu. Nanocząstki magnetytu zostały zsyntetyzowane z wykorzystaniem metody strąceniowej i ustabilizowane poliakrylanem sodu. W pierwszym etapie powierzchnia membran PVDF została poddana modyfikacji polietylenoiminą. W drugim etapie polielektrolit, umieszczony na powierzchni membrany, został wykorzystany do immobilizacji nanocząstek magnetytu. Modyfikacja membran została potwierdzona badaniami spektroskopowymi, elektronową mikroskopią skaningową i analizą elektrokinetyczną. Wpływ pH na potencjał zeta membrany PVDF potwierdził jej modyfikację membrany, gdy potencjał zeta wzrasta z obniżeniem się wartości pH. Elektronowa mikroskopia skanningowa wykazała, że powierzchnia modyfikowanej membrany jest gęsto pokryta nanocząstkami, które tworzą klastry. Badano również wpływ wartości stosowanego ciśnienia na objętościowy strumień permeatu dla różnych stężeń karboksymetylocelulozy (CMC). Ultrafiltracja wspomagana polielektrolitem z CMC została wykorzystana do usuwania żelaza(II) przy początkowym stężeniu Fe2+ wynoszącym 20 mg/l. Stężenie żelaza(II) w permeacie w przypadku membrany niepoddanej modyfikacji uległo zmianie z 0,6 do 1,0 mg/l, podczas gdy w przypadku modyfikowanej membrany stężenie to było w zakresie 0,02÷0,08 mg/l.

4

Grafting of oxidized carboxymethyl cellulose with hydrogen peroxide in presence of Cu(II) to chitosan and biological elucidation

Benghanem S., Chetouani A., Elkolli M., Bounekhel M., Benachour D.

Biocybernetics and Biomedical Engineering

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2017

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Vol. 37, no. 1

94--102

EN

The chemical interaction of chitosan (CS) is performed in the presence of sodium carbox-ymethyl cellulose (CMC) and/or oxidized CMC. The latter is obtained by the action of H2O2/CuSO4 to generate carbonyl and carboxyl groups which were increased with CuSO4 concentration. The characterization of these new materials is made by FTIR, TGA, XRD and SEM. Examination of the hemolytic potential showed that the hydrogels were non hemolytic in nature. The hydrogels were non-toxic and blood-compatible. The antibacterial and antioxidant activities of samples were investigated.

5

Natural modified starch and synthetic sizes in function of characteristics of sized yarn

Kovačević S., Dorđević S., Dorđević D.

Fibres & Textiles in Eastern Europe

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2016

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Vol. 24, no. 1 (115)

56--66

EN

The aim of this study was to investigate the changes in properties of yarn made by sizing with synthetic and natural modified corn starch. Different procedures for obtaining modified natural (corn) starch and various combinations of natural and synthetic sizes were used to explore the differences in the properties of sized yarn. The sizing process was carried out under with constant conditions in a newly developed laboratory sizing machine on twisted cotton yarns of 20×2 tex and 30×2 tex. According to the results obtained, yarn sized with synthetic sizes has substantially better properties than those which are naturally sized with modified starch. However, sometimes these differences are not significant or they do not exist at all. Twisted yarn is not always necessary in sizing in order to increased its strength but rather to protect the surface from wear and refine projecting fibers; in this case natural modified starch from corn can meet the requirements. The significance of this research is the application of natural sizes, improvement of the sizing process with natural modified sizes using new achievements in the development of the sizing process, and thus creating a positive environmental and economic impact.

PL

Celem pracy było zbadanie zmian właściwości przędz preparowanych preparacjami syntetycznymi i z naturalnie modyfikowanej skrobi. Proces nanoszenia preparacji przeprowadzono przy zachowaniu stałych warunków nowo zbudowanej laboratoryjnej maszynie. Obrabiano skręcane przędze bawełniane o masie liniowej 20 × 2 tex i 30 × 2 tex. Zgodnie z otrzymanymi wynikami przędze preparowane preparacją syntetyczną miały zdecydowanie lepsze parametry od przędz z preparacją opartą na modyfikowanej skrobi. Jednakże czasami różnice te nie determinują konieczności zastosowania preparacji syntetycznej zwłaszcza w sytuacji kiedy nie jest wymagane uzyskanie maksymalnej wytrzymałości a istotne są elementy ochrony środowiska i koszty produkcji.

6

Preparation And Properties Of Bionanocomposite Films Reinforced With Nanocellulose Isolated From Moroccan Alfa Fibres

Benyoussif Y., Aboulhrouz S., El Achaby M., Cherkaoui O., Lallam A., El Bouchti M., Zahouily M.

Autex Research Journal

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2015

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Vol. 15, no. 3

164--172

EN

Nanocellulose (NC) were extracted from the Moroccan Alfa plant (Stipa tenacissima L.) and characterised. These Alfa cellulosic nanoparticles were used as reinforcing phase to prepare bionanocomposite films using carboxymethyl cellulose as matrix. These films were obtained by the casting/evaporation method. The crystallinity of NC was analysed by X-ray diffraction, the dimension of NC by atomic force microscopy, molecular interactions due to incorporation of NC in carboxymethyl cellulose (CMC) matrix were supported by Fourier transforms infrared (FTIR) spectroscopy. The properties of the ensuing bionanocomposite films were investigated using tensile tests, water vapour permeability (WVP) study and thermogravimetric analysis. With the progress of purification treatment of cellulose, the crystallinity is improved compared to the untreated fibres; this can be explained by the disappearance of the amorphous areas in cellulose chain of the plant. Consequently, the tensile modulus and tensile strength of CMC film increased by 60 and 47%, respectively, in the bionanocomposite films with 10 wt% of NC, and decrease by 8.6% for WVP with the same content of NC. The NC obtained from the Moroccan Alfa fibres can be used as a reinforcing agent for the preparation of bionanocomposites, and they have a high potential for the development of completely biodegradable food packaging materials.

7

Synthesis of carboxymethylcellulose nanoparticles using various coiling agents

Kulikowska A., Wasiak I., Ciach T.

Inżynieria i Aparatura Chemiczna

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2014

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Nr 4

268--269

EN

Polysaccharide-based nanoparticles (NPs), due to their outstanding properties, attract much attention in the field of drug delivery systems. Presented work describes a method of carboxymethyl cellulose NPs synthesis which can serve as anticancer drugs carriers. The main goal of this research was to investigate the influence of type and amount of aliphatic amine and different carboxymethyl cellulose oxidation degree on the resulting NPs size.

PL

Nanocząstki polisacharydowe ze względu na swoje unikalne właściwości cieszą się dużym zainteresowaniem w systemach podawania leków. Prezentowana praca opisuje metodę syntezy nanocząstek karboksymetylocelulozowych, które mogą pełnić rolę nośnika leków przeciwnowotworowych. Celem wykonanych badań było zbadanie wpływu typu i ilości użytej aminy alifatycznej oraz różnych stopni utlenienia karboksymetylocelulozy na rozmiar powstających nanocząstek.

8

Carboxymethyl Cellulose Oxidation to Form Aldehyde Group

Kulikowska A., Wasiak I., Ciach T.

Challenges of Modern Technology

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2013

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Vol. 4, no. 2

11--18

EN

Oxidation of carboxymethyl cellulose (CMC) is a method of its modification, which allows to improve the functionality of this compound by increasing its reactivity. Presented work describes two methods of oxidation of carboxymethyl cellulose. The first is the conversion of CMC to its dialdehyde derivatives (DCMC) by sodium periodate. In the second method, hydrogen peroxide in the presence of iron tetrasulfophthalocyanine (FePcS) as catalyst was applied. Oxidation degree of CMC in different process parameters and time intervals was estimated using hydroxylamine hydrochloride. Modified CMC will be used in nanoparticles preparation in medical diagnostics.

9

Development of carboxymethyl cellulose/ polyphenols gels for textile applications

Krizova H., Wiener J.

Autex Research Journal

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2013

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Vol. 13, no. 2

33--36

EN

The aim of this study was to determine release rate and changes in polyphenols’ content, which were sorbed to carboxymethyl cellulose gel and subsequently desorbed. An aqueous extract of blue marc vine variety Fratava was used as a source of polyphenols. The gel was dried into a solid film and polyphenols were then desorbed again by dissolving this film in saline (isotonic) solution. Further, the influence of different times of high temperature (180°C) of drying gel on change in the amount of released polyphenols and also kinetics of their release in re-transfer of the film on the gel and solution was studied. The process simulates the possible use of carboxymethyl cellulose/ polyphenols film sorbed on textile materials and its contact with the tissues and body fluids such as course of wound healing.

10

On generalized rheological characteristics of carboxymethylcellulose solutions

Jaworski Z.

Chemical and Process Engineering

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2010

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Vol. 31, z. 4

873-888

EN

Rheological characteristics of aqueous solutions of sodium carboxymethylcellulose (CMC) were studied using a rotational cone-and-plate rheometer. Measurements of the shear stress and first normal stress difference were carried out for the range of the 9H4 type CMC solutions in the shear rate range of 0.2 to 3000 s-1. It was found that in the applied shear rate and the concentration of CMC solutions, elastic properties can predominate or be close to the viscous features. A modified model for shear characteristics of polymer solutions has been proposed and a tested procedure of deriving universal viscoelastic characteristics has been described.

PL

Badano właściwości reologiczne wodnych roztworów karboksymetylocelulozy (CMC) za pomocą rotacyjnego reometru typu stożek-płytka. Wykonano pomiary naprężenia stycznego i pierwszej różnicy naprężeń normalnych dla roztworów CMC typu 9H4 w zakresie szybkości ścinania od 0,2 do 3000 s-1. Stwierdzono, że w zbadanym zakresie stężeń roztworów CMC właściwości sprężyste mogą przewyższać lub być zbliżone do właściwości lepkich. Zaproponowano zmodyfikowany model charakterystyki ścinania roztworów polimeru i podano procedurę obliczania ich uniwersalnej charakterystyki lepkosprężystej.

11

Effect of chemical additives on flow characteristics of coal slurries

Mosa E. S., Saleh A.-H. M., Taha T., El-Molla A. M.

Physicochemical Problems of Mineral Processing

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2008

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Vol. 42

107-118

EN

In the present paper, the effect of chemical additives or reagents on rheological characteristics of coalwater slurry (CWS) was investigated. The power-law model was applied to determine the non- Newtonian properties of coal slurries. Three types of dispersants namely, sulphonic acid, sodium tripolyphosphate and sodium carbonate were studied and tested at different concentrations ranging from 0.5 to 1.5% by weight from total solids. Sodium salt of carboxymethyl cellulose (Na-CMC) and xanthan gum were tested as stabilizers at concentrations in the range of 0.05 to 0.25 % by weight from total solids. It was found that apparent viscosity and flow properties of CWS are sensitive to the use of chemical additives (dispersants and stabilizers). Among studied dispersing agents, sulphonic acid recorded the best performance in modification and reducing CWS viscosity. The best dosage of all tested dispersants was found to be as 0.75 % by wt of solids. With regard to studied stabilizers, Na-CMC recorded better performance than xanthan gum. The best dosage of investigated stabilizers was found to be as 0.1 % by wt. from total solids.

PL

W pracy badano wpływ odczynników na charakterystykę reologiczną zawiesin wodno-węglowych (CWS). Zastosowano model potęgowy do wyznaczenia nieniutonowkich właściwości zawiesin węglowych. Badano trzy typy dyspersantów: kwas sulfonowy, tripolifosforan sodu oraz węglan sodu przy różnych ich stężeniach od 0.5 to 1.5% wagowego. Zastosowano sól sodową carboksymetylocelulozy (Na- CMC) oraz gumę guarową jako stabilizatory zawiesin używając ich w ilości od 0.05 to 0.25 % wagowego. Stwierdzono, że pozorna lepkość i charakterystyka przepływu CWS są podatne na użyte dyspersanty i substancje stabilizujące. Wśród badanych dyspersantów, kwas sulfonowy odznaczał się najlepszym działaniem i wysoka redukcją lepkości CWS. Ilość użytych dyspersantów wyniosła 0.75 % wagowego. Wśród substancji stabilizujących lepszą okazała się Na-CMC niż guma guarowa. Najodpowiedniejsza ilość stabilizatora to 0.1 % wagowego.

12

Surface-active properties of CMC and xylan esters produced by transesterification with MERO

Tomanova V.

Czasopismo Techniczne. Środowisko

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2006

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R. 103, z. 7-Ś

81-88

EN

In this paper is presented a new method of preparation of polymeric surfactants from carboxymethylcellulose (CMC) and 4-O-glucuronoxylan (XY) under microwave irradiation. Partial hydrophobizations of CMC and XY were performed by transesterification method with methyl ester of vegetable oil (MERO) in homogeneous solvent systems under various reaction conditions to optimalize the preparation of water-soluble products having surface-active properties. The obtained esters were characterized by FTIR spectrometry. Their surface-active properties were tested. Most of the tested derivatives lowered surface tension of water and gave emulsions of the oil/water type with excellent emulsifying efficiency comparable to the commercial emulsifier Tween 20.

PL

W niniejszym artykule przedstawiono nową metodę otrzymywania polimerowych związków powierzchniowo czynnych na bazie karboksymetylocelulozy (CMC) i 4-O-glukoranoksylanu (XY) w polu promieniowania mikrofalowego. Transestryfikacja CMC i XY zachodziła w rozpuszczalniku (DMF) w obecności estrów metylowych zawartych w oleju MERO. Struktura otrzymanych estrów została określona metodą FTIR. Przeprowadzono również badania określające aktywność powierzchniową otrzymanych związków. Dla większości próbek zaobserwowano obniżenie napięcia powierzchniowego. Ponadto wykazano, że otrzymane związki mają podobne właściwości do powszechnie stosowanego emulgatora Tweed 20 i mogą być stosowane jako środki powierzchniowo czynne w procesie wytwarzania emulsji typu olej/woda.

13

Anionically-modified cotton and surface layer formation with polyelectrolytes

El-Shafei A., Knittel D., Schollmeyer E.

Autex Research Journal

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2006

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Vol. 6, no. 3

175--181

EN

Carboxymethyl cellulose (CMC) is a water-soluble cellulose derivative widely used in textile preparations, especially for the application of sizes, which are removed shortly after the weaving process. In this paper, a strategy is given for using CMC as an anionical polymeric modifier of cotton surfaces with permanent character-imparting stable properties, such as after cationic dyeing, durable press properties and polyelectrolyte layer formation, without the use of dangerous chemicals like chloroacetic acid or salts. Thus CMC was fixed onto cotton by using CMC and Na-hydroxydichlorotriazine as an anchoring chemical. The fabric samples before and after finishing were monitored for polyelectrolyte titration values, wet and dry crease recovery angle, and K/S values after fixation of cationic dyestuff.

14

Carboxymethylcellulose derivatives with low hydrophilic properties

Machado G. O., Regiani A. M., Pawlicka A.

Polimery

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2003

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T. 48, nr 4

273-279

EN

New kinds of cellulose derivatives have been obtained by modification of sodium and lithium carboxymethylcellulose (NaCMC and LiCMC, respectively) with commercial octadecylisocyanate (OctI) and hexamethylene-diisocyanate (HDI). The CMC samples were obtained from sugar cane bagasse pulps using sodium hydroxide and anthraquinone mixture. The structural changes of modified samples were observed using infrared spectroscopy (IR), solid state C-13 NMR and thermal analysis (TGA). The samples surfaces were visualized using scanning electron microscopy (SEM) method. The presence of characteristic urethane group absorption bands in the region of 1650-1720 cm(-1) in IR spectra and at 159 ppm in C-13 NMR spectra indicates the formation of the product.

PL

Wymienione w tytule pochodne celulozy otrzymano w reakcji soli sodowej i litowej karboksymetylocelulozy (CMC, odpowiednio NaCMC i LiCMC) z izocyjanianem oktadecylo-wym (Octl) i diizocyjanianem heksametylenowym (HDI). Źródłem użytych próbek CMC były wytloczyny trzciny cukrowej. Strukturę wyjściowych NaCMC i LiCMC, a także produktów ich reakcji z HDI i Octl scharakteryzowano metodami IR oraz 13C NMR w ciele stałym. Metoda analizy termicznej(TGA) posłużyła do oceny termostabilności omawianych substancji. Powierzchnie próbek badano za pomocą skaningowego mikroskopu elektronowego. Na przebieganie reakcji NaCMC i LiCMC z izocyjanianami wskazuje obecność pasm absorpcji odpowiadających grupom uretanowym (widma IR w zakresie 1650-1720 cm"1 i widma 13C NMR, 5 = 159 ppm). Wyniki TGA świadczą o znacznym zmniejszeniu hydrofilo-wości produktów modyfikacji CMC w porównaniu z wyjściowymi próbkami NaCMC i LiCMC. Długość łańcucha węglowodorowego użytych izocyjanianów nie wpływa na stopień zmniejszenia hydrofilowości, natomiast znacznie zmienia przebieg degradacji cieplnej produktów modyfikacji.

15

Etery celulozy jako zagęstniki polimerowe. Cz. 1. Nie hydrofobizowane pochodne

Lipka E., Spychaj T.

Ekoplast

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1999

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Nr 16

59-72