• Journal of the Korean Wood Science and Technology
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• v.22 no.4
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• pp.51-60
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• 1994

Chlorodeoxycellulose derivatives have recently assumed importance since the halogen atoms can be changed with other functional groups to afford new derivatives of cellulose. Also, chlorinated cellulose has been employed as an intermediate in the preparation of various functional cellulose derivatives. In this study chlorodeoxycellulose was prepared by reaction of methylcellulose with mathanesulfonylchloride in N,N-dimethylformamide. Subsequently, conversion of the above chlorinated cellulose to unsaturated celluloseen was carried out by potassium tertiary butoxide in dimethyl sulfoxide. An anhydrocellulose as an intermediate for the reactive functional derivatives was made by simple alkali treatment. Preparation condition of allylated methylcellulose by using allylchloride and its thermal behavior were also described.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.16 no.1
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• pp.19-25
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• 2010

It is becoming increasingly important to utilize alternative raw materials for plastic industries other than petrochemical-based plastics. Cellulose derivatives were the bases of the original synthetic plastics. Cellulose and its derivatives, especially the widely used cellulose acetate (CA), constitute one of the main classes of raw materials for production on artificial fibers, films, plastics etc. CA is one of the well known polymers produced from naturally available plant substance. Many researches have focused on the isolation of cellulose from the plant cells to use them as cellulose derivatives and composite materials. Chemical and mechanical treatments provide changes on the molecular structures influencing the fundamental properties of these naturally abundant polymer. The aim of this review article is to review biodegradation, synthesis, formation, and utilization of cellulose esters, especially di-acetate, used in packaging related researches.

• Bulletin of the Korean Chemical Society
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• v.27 no.4
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• pp.519-523
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• 2006

Poly(dimethyl siloxane) (PDMS) has been employed as a microchip material for DNA separation in microfluidic condition. Different sieving molecules such as cellulose derivatives having glucose building block (methyl cellulose (MC), hydroxyethyl cellulose (HEC), and hydroxypropyl methyl cellulose (HPMC)) and polyethylene oxide (PEO) having linear (ring-opened ethylene oxide) unit were used and their performance was compared in terms of separation efficiency and resolution. In general, PEO showed better separation performance than cellulose derivatives probably due to the nature of linear shape polymer conformation. It was possible to perform at least 15 consecutive running with 1.2% PEO at the electric field strength around 200 V/cm. Fast analysis of the standard $\Phi$X 174 RF DNA/Hae III (less than 130s) was obtained with the number of the theoretical plate around 250,000/m. Our PMDS microchip was applied to the measurement of CAG repeat number, which is related to male infertile disease.

• Archives of Pharmacal Research
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• v.20 no.1
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• pp.68-71
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• 1997

Penicillin sensor was prepared by immobilizing penicillinase (Pcase) on $H^{+}$-selective carboxylated poly (vinyl chloride) (PVC-COOH) membrane or cellulose filter membrane. The immobilization techniques are as follows. Pcase was immobilized with GTH on $H^{+}$-selective PVC-COOH membrane or some amount of BSA was dropped on that membrane. Another method to make immobilization is to mix type I Pcase with GTH and drop on a cellulose filter membrane. According to immobilization techniques, there were some differences in response properties of enzyme electrodes, however, all electrodes responded to Pcase-resistant penicillin derivatives. Pcase immobilized on cellulose filter membrane with $H^{+}$-selective PVC membrane eletrode was more stable and more sensitive to penicillinase-resistant penicillin derivatives than any other immobilization techniques.

• Polymer(Korea)
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• v.25 no.2
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• pp.279-292
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• 2001

Two kinds of (hydroxypropyl)cellulose(HPCs) with different molar substitution (MS) and three types of derivatives based on the HPCs: (acetoxypropyl)celluloses, (ethoxypropyl)celluloses, and (cyanoethoxyprofyl)celluloses were synthesized, and their thermal and mesomorphic properties were investigated. All samples, which exhibit cholesteric reflection colours at room temperature, formed right-handed helicoidal structures whose optical pitches (λ$_{ms}$ ) increase with temperature. However, the isotropization ($T_{i}$) and glass temperatures, the magnitude of λ$_{m}$ of the mesophase at the same temperature, and the temperature dependence of λ$_{m}$ of the investigated derivatives highly depended on MS and the length and structure of the side chain introduced in HPC. The results were discussed in terms of the difference in the polarity and flexibility of the substituents and the distance between the main chains. For all derivatives, Am values approached infinity at temperatures above the $T_{i}$, of the mesophase, and no reversal in the sense of the pitch with temperature was detected.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.27-28
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• 2006

Chromatographic separation of enantiomers by high-performance liquidchromatography (HPLC) has considerably advanced in the past two, and many optically active polymers have been developed to be usedaschiral stationary phases (CSP). Among many CSPs, cellulose-andamylose-based CSPs are most attractive from the viewpoints of theirwide applicability and easy availability. The polysaccharides are readily modified to ester and carbamates. The derivatives have been used as CSPs after being coated on macroporus silica gel. Here, the CSPs based on phenylcarbamate derivatives of these two polysaccharides will be mainly discussed. The immobilization of the derivatives on silica gel will also be discussed.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.649-652
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• 2013

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.3
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• pp.51-59
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• 1997

Dissolving pulp is a low yield(30∼35%) bleached chemical pulp that has a high cellulose content (95% or higher) suitable for use in cellulose derivatives such as rayon, cellulose acetate. This research was studied for dissolving pulp preparation as the raw material of viscose rayon from commertial pulps. (TMP, CP, DIP) In the change of pulp(cellulose) characteristics after sodium hypochlorite and solvolysis treatment. the following results were obtained In the case of sodium hypochlorite pretreatment, we have obtained pulp that high purity cellulose, but degree of polymerization was inclined to decrease less than 170∼240. Comparing sodium hypochlorite pretreatment and solvolysis pretreatment, solvolysis pretreatment is superior to sodium hypochlorite process for making dissolving pulp. We think that the low degree of polymerization of cellulose because of increasing degradation of cellulose during delignification treatment.

• Proceedings of the Korean Fiber Society Conference
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• 1990.06a
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• pp.7-9
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• 1990

• Journal of the Korean Applied Science and Technology
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• v.17 no.4
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• pp.273-278
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• 2000

Cellulose tosylate(CT) was prepared by reaction of cellulose with p- toluenesulfonylchloride in DMAc/LiCl homogeneous system. In order to study a reversible photoisomerization of disperse red 1(DR-1) attached on natural polymer, cellulose tosylate containing DR-1(DR-1/CT adduct) was prepared at $110^{\circ}C$ in DMAc, and the changes of UV/Vis spectra of its solutions and thick film were investigated by alternate irradiation technique. Form the UV/Vis spectra of DR-1/CT adduct dissolved in cosolvents, such as DMAc, DMAc/THF, DMAc/benzene, and DMAc/chloroform and irradiated with 360 nm and 450 nm ligths, we found out changes of UV/Vis spectra were reversible in all solvents systems and we found out changes of UV/Vis spectra were reversible at thick film, also.