• Journal of the Korean Applied Science and Technology
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• v.27 no.3
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• pp.378-384
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• 2010

Regenerated cellulose was prepared from Buckeye wood pulp V60 via dissolution in N-methylmorpholin N-oxide (NMMO) solvent system. The effect of antioxidants such as, n-propylgallate (PG), tris(nonylphenyl) phosphite (TRIS), ethylenediamine tetraacetic acid disodium salt (EDTA), and magnesium sulfate on the properties of regenerated cellulose was studied using X-ray diffraction, copper index calculation, and viscometry. Only addition of more than 0.01% of PG into NMMO solvent was effective to avoid the reduction of the degree of polymerization(DP) of regenerated cellulose during dissolution at $110^{\circ}C$. However, the early stage(within 0.5h of dissolution process) degradation of cellulose was not prevented eventhough up to 0.5% PG was appled to hot NMMO system. In addition, to recover the expensive NMMO after cellulose regenerating process, the washing filtrate was studied using simple techniques, such as refractive index, pH, and conductivity measurements. Through conductivity measurement result, 4-time of washing was enough to remove the NMMO completely from regenerated cellulose.

• The Research Journal of the Costume Culture
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• v.12 no.5
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• pp.737-742
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• 2004

The purpose of this study is restoration for tearing strength of the durable press (DP) finished 100% cotton fabric by enzymatic treatment. Dimethylol Dihydroxy Ethylene Urea (DMDHEU) was used as a DP finish chemical. Enzymes (cellulase, pectinase, protease, lipolase) were selected based on their specific reaction activities. Ideal application of the enzymes for this work was to remove cross-links created by DMDHEU on the surface of the fibers to offer migration property between microstructures of cellulose, yet cross-links that exist inside of the fibers are still remained to impart effect of wrinkle resistance. Physical characteristics (tearing strength, wrinkle recovery, FT-IR) of enzyme treated samples were measured and compared. It was found out that, in case of enzyme treatment, most of enzymes didn't have a great effect on tearing strength, but, in case of Protease, tearing strength increased at DMDHEU 2% treatment. As a result of an experiment on wrinkle recovery of the textiles treated with enzyme making density of DMDHEU different whenever respective experiment was made, it was discovered that density of DMDHEU increased as wrinkle recovery increased and, in the relation to enzyme treatment especially in Lipase enzyme treatment, the lesser density of DMDHEU, the more wrinkle recovery increased.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.4
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• pp.28-34
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• 2001

Korea traditional handmade paper, Hanji, has been known for more than thousand years for its high strength, high whiteness, high gloss, good ink reception and long lasting quality. Main component fiber of the Hanji is called 'Dak', which is the bast fiber of the Korea paper mulberry ($\textit{Broussonetia kazinoki}$). Dak has long fiber length, and high cellulose DP, if processed properly. The quality of Hanji is partly from the superior quality of Dak over wood fiber, and partly from the traditional papermaking process. The traditional papermaking process includes pulping, bleaching, refining, use of natural polymer, and sheet making process. Every traditional process has its special role. Comparisons between the modern papermaking technology and the traditional process were made in this study. The traditional process effectively protected cellulose DP in pulping and bleaching process, protected fiber length in refining process, and developed the high strength in the sheet forming process over the modern papermaking process.

• The Korean Journal of Ecology
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• v.21 no.1
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• pp.73-80
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• 1998

Peroxidase has been isolated to apparent homogeneity from earthworm, Lumbricus rubellus, using ammonium sulfate fractionation, Sephacryl S-2000 gel filtration, CM-cellulose cation exchange chromatography and native-PAGE elution. Some of its enzymatic characteristics were examined. The optimum pH for gruaiacol oxidation of earthworm peroxidase was determined to be 6.0, and the $K_{m}$ values against guaiacol and $H_2O_2$ were 1.25 mM and 3.4mM, respectively. When various compounds were tested as the possible substrates of the enzyme, o-dianisidine was used as the substrate. However, earthworm peroxidase could not oxidize esculetin and ferulic acid as substrates, suggesting the different characteristics of the enzyme from plant peroxidases. The optimum pH for veratryl alcohol and $H_2O_2$ oxidation was determined to be 2.5 when lignin peroxidation activity was examined. The $K_{m}$ values for veratryl alcohol and $H_2O_2$ were 0.02 mM and 0.13 mM, respectively. Furthermore, the earthworm peroxidase could oxidize phenoxyherbicides such as 2,4-D, 2,4-DP and MCPA as substrates. The optimum pHs for 2,4-D, 2,4-DP and MCPA were determined to be 4.0, 2.0 and 2.0, respectively. The most available substrate was 2,4-DP, followed by MCPA and 2,4-D when their peroxidation activities were compared.

• Textile Coloration and Finishing
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• v.15 no.4
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• pp.17-23
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• 2003

Fourier transform infrared spectroscopy(FT-IR) was used to characterize the intermolecular ester crosslinkages in cotton cellulose. The FT-IR data show that the band of the ester carbonyl group can be separated from overlapping carboxyl/carbonyl band by converting carboxyl group to carboxylate. When esterification occurs between a polycarboxylic acid and cotton cellulose, the carbonyl groups retained in the cotton exist in three forms; ester, carboxyl, and carboxylate anion. The FT-IR data were also correlated to the durable press rating result obtained. The appearance of BTCA-finished durable press silk/cotton fabrics were improved.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.4
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• pp.693-699
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• 2010

General transformer's life is known as paper insulation' life. If a transformer is degraded by these aging factors, it is known that electrical, mechanical and chemical characteristics for transformer's oil-paper are changed. When the kraft paper is aged, the cellulose polymer chains break down into shorter lengths. It causes decrease in both tensile strength and degree of polymerization of paper insulation. The paper breakdown is accompanied by an increase in the content of furanic compounds within the dielectric liquid. In this paper it is aimed at analysis on correlation between aging characteristics for insulating diagnosis of thermally aged paper. For investigating the accelerated aging process of oil-paper samples accelerating aging cell was manufactured for estimating variation of paper insulation during 500 hours at $140^{\circ}C$ temperature. To derive the results, it was performed analysis such as tensile strength(TS), depolymerization(DP), dielectric strength(DS), relative permittivity, water content(WC) and furan compound(FC) for aged paper. Also for analyzing correlation between insulating degradation characteristics, we used linear regression method. As as results of linear regression analysis, there was a close correlation between TS and DP. WC, FC. But dielectric strength was a weak correlation with aging time.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.5
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• pp.23-32
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• 2015

In this study, chemical and physical changes of dissolving pulps which have similar viscosity by dry milling and fractionation were investigated. We used two types of dissolving pulp made from wood and cotton linter fiber, respectively. Dry milling was executed by knife cutter and pulp powders were fractionated by sieve shaker into 4 grades. We analyzed fiber properties, crystallinity index, viscosity, molecular weight of pulp sheet and powders. It was found that poly-dispersity index of cotton linter pulp was smaller than that of wood pulp, meaning that cotton pulp has more narrow molecular weight distribution. It was assumed that these were related to exposure times to chemical treatment which cut cellulose chains not evenly. At least 4 times of chemical treatments for wood pulp were executed and only two times of chemical treatments for cotton linter pulp were done. After dry milling average molecular weight and crystallinity index of cotton linter pulp powders were reduced and these were related to fines content and shape of pulp powders.

• Textile Coloration and Finishing
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• v.9 no.6
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• pp.58-67
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• 1997

PTCA(1,2,3-propanetricarboxylic acid) and BTCA(1,2,3-butanetetracarboxylic acid) are selected as new nonformaldehyde agents for ester crosslinking of cotton cellulose to replace the traditional DMDHEU reagent. A goal of this research is to propose unknown ester mechanism of cotton cellulose by PTCA or BTCA using crystal structure model suggested by Meyer and Takahashi. In pursuit of these goals, we have treated 100% cotton broad cloth with PTCA or BTCA and different catalysts. They were used with $NaH_2PO_2,\;NaH_2PO_4,\;Na_2HPO_4,\;NaH_2PO_2,\;Na_3PO_4,$ catalysts to produce nonformaldehyde fabric finishes. Treatments were applied to all cotton fabrics using a pad-dry -cure process. The esterfication of cotton treated with BTCA or PTCA was investigated using Fourier transform infrared(FT-IR) spectra and the breaking strength, abrasion retention and discoloration properties were determined to prove the durable finished fabrics. Patterns with respect to abrasion resistance were more complex. Because PTCA and BTCA add-ons were comparable, the data suggest that the more effective catalysts, $NaH_2PO_2$ and mixed phosphate $NaH_2PO_2/NaH_2PO_4$) are effecting either a great number of crosslinks in the cotton or producing crosslinks that differ in actual structure.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.8
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• pp.1060-1068
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• 1998

The effects of various catalysts and softners on the anti-crease finish of ramie with glyoxal were investigated. A number of metal salts commonly used as Lewis acid catalysts in DP finishing of cotton with formaldehyde and N-methylol agents were screened for glyoxal treatment of ramie fabric. Various organic and inorganic acids were mixed with Lewis acid catalyst as co-catalysts to improve catalytic activity. As a result, the combination of aluminum sulfate and citric acid was proven highly effective in catalyzing the crosslinking of ramie cellulose by glyoxal under lower curing temperature. With a mixed catalyst, performance properties, such as whiteness and tearing strength as well as wrinkle recovery of treated ramie fabric were improved as compared with that treated with aluminum sulfate alone. Additional improvement of tearing strength and wrinkle recovery was achieved by applying silicons softner in the treatment bath.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.7
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• pp.1078-1084
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• 2002

Cotton fabrics were treated with 1,2,3,4-butanetetracarboxylic acid(BTCA) to impart durable press performance, which is formaldehyde-free DP finishing reagent. The pore structures of BTCA treated cottons were compared using a reverse gel permeation chromatographic technique(reverse GPC). A series consisting 4 kinds of water soluble sugars was used to study the elution characteristics of columns prepared from cotton fibers. From these data, differences in pore size distribution in the control and BTCA treated cottons were distinguished. BTCA crosslinks cellulose molecules provided wrinkle resistance to the treated cotton fabrics through ester linkages. Although crosslinking of cotton with BTCA reduced accessible internal volume across the entire range of pore size, differences in line pores were larger than in small pores. BTCA treated cotton exhibited reductions over 40% in large pore sizes.