• Clean Technology
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• v.19 no.2
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• pp.121-127
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• 2013

The objective of this study is optimization of extrusion process for preparation of pellet-type adsorbents employed with alum sludge. Effects of water content and methyl cellulose as a binder on the possibility of extrusion and physical properties of pellet-type adsorbents were investigated. The physical characteristics of the pellet-type adsorbents were studied using nitrogen adsorption and compression strength. With a ratio of water to sludge, 63/100, the adsorbent was well extruded with a cylindrical form and the compressive strength was the highest. With increasing methyl cellulose content, the compressive strength of pellet-type adsorbent could be improved, but the specific surface area decreased. The breakthrough time of the hydrogen sulfide could be increased significantly through calcination and the breakthrough capacity reached to 1,700 mg/g, which seems to be due to increase of surface area during calcination.

• Polymer(Korea)
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• v.37 no.6
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• pp.802-808
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• 2013

The purpose of this study was to develop an aloin-loaded wound dressing with an enhanced healing effect. The cross-linked hydrogel films were prepared with poly(vinyl alcohol) (PVA) and carboxyl methyl cellulose (CMC) using a freeze-thawing (F-T) method. Their gel properties, release of drug, in vivo wound healing effect and histopathology were then evaluated. In the wound healing test, this aloin loaded PVA/CMC hydrogel showed faster healing of the wound made in rat dorsum than the aloin carbomer 934 gel or the control (carbomer 934 gel) due to phytochemical activity of aloin and moisture of CMC. In conclusion, the aloin-loaded wound dressing composed of 5% PVA, 5% CMC and 0.125% aloin is a potential wound dressing with enhanced wound healing effect.

• Applied Chemistry for Engineering
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• v.32 no.5
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• pp.556-561
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• 2021

Recently, iron oxide nanoparticles have been used as the subject of many studies on drug delivery system (DDS) due to their excellent magnetic properties and biocompatibility in response to external magnetic fields. In this study, hyaluronic acid-superparamagnetic microneedles (HA-SMNs) and carboxy methyl cellulose-superparamagnetic microneedles (CMC-SMNs) containing superparamagnetic iron oxide nanoparticles (SIONs) were prepared with HA and CMC as a matrix materials of MNs (microneedles). Various properties of SMNs were then investigated with scanning electron microscopy (SEM), superconducting quantum interference device-vibrating sample magnetometer (SQUD-VSM), frequency mixing magnetic detection (FMMD), and polymer/bio membrane. The SQUID-VSM measurements showed superparamagnetism of HA-SMNs and CMC-SMNs containing SIONs. The FMMD results demonstrated that the signal intensity changed significantly as the concentration of SIONs increased. In addition, SMNs exhibited the average skin permeability intensities on the bio membrane for HA-SMNs and CMC-SMNs were 92.5 and 98.5%, respectively. These results suggested that SMNs could be utilized as deliver materials for a TDDS and MR molecular imaging.

• Journal of Conservation Science
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• v.34 no.5
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• pp.397-405
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• 2018

Currently, there are very few studies on Korean wall paintings. Therefore, this study discusses the current conditions of wooden paintings and the characteristics of the adhesive agent in the painting layer separation. Korean land pine was chosen as the support, while white oysters shells, orpiment, red ocher, Noerok, and azurite were used as pigments. With four adhesive agents, including animal glue, Gelidium, methyl cellulose, and PVAc (caparol binder), a comparative experiment was conducted, by dividing them into two concentrations, of 0.5% and 1.5%. The temperature, humidity, and ultraviolet rays, which are contributing environmental factors in cultural assets after fixing, were artificially investigated. After deterioration, observed color difference, fixing, and the surface. Results showed that the animal glue strongly fixing all the colored layers compared to the other adhesives; however, azurite had a partial change when used outdoors. With Gelidium, which functioned similar to animal glue, the azurite was affected by the ultraviolet rays; nevertheless, despite the variations in temperature and humidity, it had the best gripping force compared to the other adhesive agents. Methyl cellulose was glossy at a high concentration, and was relatively strong against rapid changes in temperature and humidity. PVAc significantly reduced the binding force, compared to other adhesive agents.

• Journal of Korea Foresty Energy
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• v.19 no.2
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• pp.86-92
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• 2000

The liquefactions of $\alpha$-cellulose(Sigma Chemical, C-8002, 47H0383) was prepared in the presence of phenol using sulfuric acid as a catalyst under $N_2$ gas protection at $180^{\circ}C$ for 60minutes to examine its components. The ratio of $\alpha$-cellulose to phenol was 1: 6.2(w/w), and that to sulfuric acid was 1: 0.05(g/$m\ell$). The yields of liquefaction were calculated after the liquefied mixtures were passed through 1G4 glass filter. The luquefied product of $\alpha$-cellulose was analyzed using GC-MS Spectormeter. The 12 compounds identified by GC-MS Spectrometer, of which peak area covers 54% as 2,4-dimethyl phenol, p-isopropyl phenol, 1-ethyl-3,5-dimethyl benzene, o-isopropyl phenol, (E)-2,4\` dihydroxy-stilbene, 2,2\`-methylene-bisphenol, 4,4\`-methylenebisphenol, 3-methyl-2-hydroxyphenyl-(E)-2-hydroxyl-4\`-methoxy-stilbene, 1-phyenyl-1-(4\`hydroxyphenyl)methanol phenol derivatives. From this results, the reaction pathways of the liquefaction of cellulose were proposed through electrophilic substitution reaction. Phenol as a solvent might react with the reaction intermediates as well in the cellulose liquefaction.

• Food Engineering Progress
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• v.14 no.2
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• pp.118-126
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• 2010

The fibrous material fraction as a by-product from the commercial aloe vera gel processing was obtained and freeze dried. The physicochemical characteristics such as the proximate composition, crystalline/surface structures and several physical functionalities including the water holding capacity (WHC), swelling capacity (SW), oil holding capacity (OHC), emulsion/foam properties and viscosity properties of this powdered sample (100 mesh) were investigated and analyzed by comparison with commercial $\alpha$-cellulose as a reference sample. The total dietary fiber content of powdered sample was very high as much as 87.5%, and the insoluble dietary and soluble dietary fiber content ratios were 77.6 and 22.4%, respectively. The FT-IR spectrum of powdered sample showed a typical polysaccharide property and exhibited a x-ray diffraction pattern for cellulose III and IV like structure. SW (8.24${\pm}$0.15 mL/g), WHC(6.40${\pm}$0.19 g water/g solid) and OHC(10.32${\pm}$0.29 g oil/g solid) of freeze dried aloe cellulose were about 3.3, 1.4 and 2 times higher than those of commercial $\alpha$-cellulose, respectively. Aloe cellulose (~2%, w/v) alone had no foam capacity while improved the foam stability of protein solution (1% albumin+0.5% $CaCl_{2}$) by factor of 300%. Emulsion capacity of 2%(w/v) aloe cellulose was about 70% level of 0.5%(w/v) xanthan gum, but its emulsion stability was about 1.2 times higher than that of xanthan gum. Also, aloe cellulose containing CMC (carboxyl methyl cellulose) of 0.3%(w/v) showed a very good dispersity. Aloe cellulose dispersion of above 1%(w/v) exhibited higher pseudoplasticity and concentration dependence than those of $\alpha$-cellulose dispersion, indicating the viscosity properties for new potential usage such as an excellent thickening agent.

• Applied Chemistry for Engineering
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• v.16 no.2
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• pp.267-274
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• 2005

Preparation of cellulose type underwater non-segregation admixture was attempted and the hardening characteristics of underwater concrete according to the addition of this admixture was investigated in order to make underwater concrete with the compressive strength ratio of 0.8 to that of concrete manufactured in common atmosphere. The proposed underwater non-segregation admixture consisted of methyl cellulose of 0.4% by weight, silicon type antifoaming agent of 20% by weight, and sodium aluminate of 0.1% by weight to the amount of cement as setting accelerant, respectively. As the proposed non-segregation admixture was increased, the amount of suspended solid decreased, air content in concrete was increased but the flow loses by elapsed time did not change. The proper amount added of the proposed non-segregation adimixture was 0.8 wt% to the amount of cement. The compressive strength of the test sample underwater concrete manufactured by the addition of the proposed admixture was $325Kg/cm^3$, and the ratio of compressive strength of this sample concrete to that of a concrete manufactured in air was 0.94.

• Macromolecular Research
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• v.10 no.3
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• pp.140-144
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• 2002

Dispersion polymerization of acrylamide was carried out in the media of methyl alcohol/$H_2O$ mixtures using hydroxypropyl cellulose and ammonium persulfate as steric stabilizer and initiator, respectively. The effects of concentrations of initiator and steric stabilizer, amount of monomer, polymerization temperature, methyl alcohol/$H_2O$ ratio, and purification of monomer and nitrogen purge on the particle size of the latices and molecular weight of the polymers were investigated. The average particle diameter increased with increasing concentration of initiator, water content in methyl alcohol/$H_2O$ media, and polymerization temperature, but decreased with monomer and stabilizer concentrations. The viscosity average molecular weight increased with increasing concentrations of monomer, steric stabilizer, and water content in dispersion media, but decreased with initiator concentration and polymerization temperature. The PAM polymers prepared with the purified monomer and the nitrogen purging before the reaction showed the highest molecular weight.

• Applied Chemistry for Engineering
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• v.4 no.1
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• pp.188-195
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• 1993

Polyelectrolyte complexes and graft copolymers as biomaterials were synthesized from the water soluble cellulose derivatives. Polyelectrolyte complexes have been prepared from carboxymethyl cellulose (CMC) and gelatin. Graft copolymers(Mc-g-AA) were synthesized by grafting acrylic acid (AA) onto methyl cellulose(MC). (Mc-g-AA) and gelatin polyelectrolyte complexes were also prepared. The optimum conditions of each sample were investigated after chemical crosslinking or heat treatment. The preliminary results show that these materials might be interesting for biomedical applications.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2399-2402
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• 2013

The catalytic pyrolysis of cellulose was carried out over SAPO-11 for the first time. Pyrolyzer-gas chromatography/mass spectroscopy was used for the in-situ analysis of the pyrolysis products. The acid sites of SAPO-11 converted most levoglucosan produced from the non-catalytic pyrolysis of cellulose to furans. In particular, the selectivity toward light furans, such as furfural, furan and 2-methyl furan, was high. When the catalyst/cellulose ratio was increased from 1/1 to 3/1 and 5/1, the increase in the quantity of acid sites led to the promotion of deoxygenation and the resultant increase of the contents of light furan compounds. Because furans can be used as basic feedstock materials, the augmentation of the economical value of bio-oil through the catalytic upgrading over SAPO-11 is considerable.