• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.3
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• pp.59-68
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• 2013

The cotton contains various impurities such as protein, wax, pectins, coloring matter, even though cotton has been a major source of pure cellulose. The purification processes have been commonly applied to obtain the pure cellulose. However the excessive purification treatments could lead to the damage in the cellulose structure which could result in the degradation of cellulose and the limited application of cotton cellulose. In this study, the changes in cellulose structural properties such as crystallinity and DP(degree of polymerization) by the various conditions of the purification processes were investigated. The less toxic agents such as hydrogen peroxide and sodium silicate were applied for the purification treatment in this study. The increase in the process times, the temperature and the applied amount of chemical agents resulted in the more purified cellulose. The DP of cotton cellulose was increased at the first weak conditions by the reduction of small molecules such as pectin, wax, and so on. Especially the 2 % addition amount of $H_2O_2$ with $Na_2SiO_3$ resulted in the higher value in the DP and the brightness compared to the 1.5 % addition amount of $H_2O_2$. However, the 4 % addition amount of $H_2O_2$ with $Na_2SiO_3$ showed the decreased value because of excessive treatment. In case of the changes in the crystallinity (Gjk), the highest value of the crystallinity was obtained by the 2% addition amount of $H_2O_2$ on the cotton cellulose, which showed similar with the change in the DP.

• Textile Coloration and Finishing
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• v.5 no.3
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• pp.221-228
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• 1993

Cellulose acetate and methyl cellulose were synthesized from waste cellulose in order to make waste knit on value added highly. Crystal waste cellulose by oxidation using $HIO_4$ and then acetylation was decrystallized. A degee of crystallinity was measured by X-ray diffraction and the structure was identified by FT-IR spetroscopy, respectively. Cellulose acetate was prepared from the reaction of decrystallized cellulose with acetic acid, cone-$H_{2}SO_{4}$ and acetic anhydride. Also, structure identification by FT-IR and a degree of crystallinity by X-ray diffraction were performed. DS of the synthesized cellulose acetate was 2.8 and viscosity average molecular weight was 238,000. Also, methyl cellulose was synthesized by treating cellulose acetate with NaOH and iodomethane. DS of the synthesized methyl cellulose was 3.0. Glucose unit with three hydroxy groups was all substituted by methoxyl groups. It was identified by FT-IR spectroscopy. Also, the thermal properties of the synthesized methyl cellulose were examined by DSC. It shewed two shewed melting peaks at 22$0^{\circ}C$ and 24$0^{\circ}C$ in the 2nd scan. It proved that DS=3.0 of methyl cellulose was a thermotropic liquid crystal.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.89-89
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• 2011

Cellulose섬유의 염색시 섬유가 물속에 침지되면 섬유표면은 음전하가 형성되어, 용액 속에서 음이온으로 존재하는 염료와의 반발력으로 인해 염료가 섬유에 접근하기가 어려워지며 따라서 염색이 원활하게 이루어지지 않는다. 그러나 염욕에 염화나트륨(sodium chloride, NaCl)이나 망초 즉, 황산나트륨(Glauber's salt, sodium sulfate, Na2SO4)과 같은 전해질을 첨가하면, 양이온인 sodium 이온이 섬유표면과 음이온 염료사이의 반발력을 감소시킨다. 따라서 음이온의 염료는 섬유표면에 접근할 수 있고, 고유한 인력으로 염색이 가능하게 된다. 현재 Cellulose섬유의 상업적인 반응성염료 염색공정뿐만 아니라 최근 연구에서는 전해질 중 대부분 분말망초를 대부분 사용하고 있다. 그러나 분말망초는 별도의 용해과정이 필요할 뿐 아니라, 과량 사용시 용해되지 않은 분말이 섬유 표면에 흡착될 경우 불균염을 초래할 우려 등의 단점이 있다. 이와 같이 작업효율성을 향상시키고 염색을 효율적으로 진행시키기 위해 최근 액상형의 망초가 도입되고 있다. 이 연구에서는 분말 및 액상 망초를 조제로 사용하여 3종류의 Cellulose섬유를 반응성염료로 염색하였다. 담색, 중색, 농색 3가지 염료 농도에 대해 투입하는 망초의 type에 따라 각각의 Cellulose섬유별 균염성 정도에 대하여 비교해 보았다.

• KSBB Journal
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• v.11 no.5
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• pp.550-556
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• 1996

A complex medium was developed for the production of microbial cellulose by Acetobacter xylinum ATCC 23769. The optimum concentration of each nutrient for the production of microbial cellulose was determined to be 10g peptone, 20g yeast extract, 5g glucose, 1.56g Na2HPO4, 1.8g KH2PO4, 0.05g MgSO4, 0.002g FeCl3, 5g citric acid and 10 mL ethanol per liter. With synergistic effects of citric acid and ethanol, cellulose productivity achieved in developed medium was 0.446 gram of cellulose per gram glucose for static culture, which is much higher than reported values. Cell growth and the cellulose production in the developed medium under static culture was also investigated.

• Textile Coloration and Finishing
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• v.7 no.2
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• pp.32-39
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• 1995

Various grades of hydroxyethyl cellulose (HEC, MS 0.65-3.20) were prepared throngh reaction of the knit-cotton-waste with ethylene oxide(EO). The knit-cotton-waste was composed of 98% of $\alpha$-cellulose and 2% of other components, and the cellulose was highly pure. The molar ratio of EO to knit-cotton-waste and that of NaOH to knit-cotton-waste, and the agitation speed were the important factors determining the molar substitution(MS) during the preparation of HEC. The MS of HEC was remarkably increased with increasing molar ratio of EO' to knit-cotton-waste. When the molar ratio of EO to knit-cotton-waste was 3.5, that of NaOH to knit-cotton-waste was 1.25, and agitation speed was 450rpm, it was possible to prepare HEC of MS 2.5. The structure and crystallinity of HECs prepared were determined by FT-IR and X-ray diffraction.

• Fibers and Polymers
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• v.3 no.1
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• pp.1-7
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• 2002

Cellulose carbonate was prepared by the reaction of cellulose pulp and $CO_2$ with treatment reagents, such as aqueous $Zncl_2$ (20-40 wt%) solution, acetone or ethyl acetate, at -5-$0^{\circ}C$ and 30-40 bar ($CO_2$) for 2 hr. Among the treatment reagents, ethyl acetate was the most effective. Cellulose carbonate was dissolved in 10% sodium hydroxide solution containing zinc oxide up to 3 wt% at -5-$0^{\circ}C$. Intrinsic viscosities of raw cellulose and cellulose carbonate were measured with an Ubbelohde viscometer using 0.5 M cupriethylenediamine hydroxide (cuen) as a solvent at $20^{\circ}C$ according to ASTM D1795 method. The molecular weight of cellulose was rarely changed by carbonation. Solubility of cellulose carbonate was tested by optical microscopic observation, UV absorbance and viscosity measurement. Phase diagram of cellulose carbonate was obtained by combining the results of solubility evaluation. Maximum concentration of cellulose carbonate for soluble zone was increased with increasing zinc oxide content. Cellulose carbonate solution in good soluble zone was transparent and showed the lowest absorbance and the highest viscosity. The cellulose carbonate and its solution were stable in refrigerator (-$5^{\circ}C$ and atmospheric pressure).

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.3
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• pp.3-10
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• 2015

In this study, we evaluated properties of pulp treated with swelling agent and swelling concentration. We used swelling agent, such as NaOH, DMSO, urea. One of them, pulps treated with NaOH from 0 to 5% measured WRV, beating efficiency, crystallinity and aspect ratio. We identified that NaOH when freeness reaches 100mL CSF was the shortest, on the other hand, WRV didn't change. Because NaOH is good beating efficiency, when pulp treated with various concentration of NaOH from 0 to 5%, pulp treated 1% NaOH was best beating efficiency. However, WRV, crystalline structure and crystallinity didn't change. The more NaOH concentration increased, the more aspect ratio increased, but when NaOH concentration exceeds 3%, aspect ratio decreased. As a result, pulp treated with 1% NaOH was the greatest beating efficiency and WRV, chemical structure didn't change.

• Journal of Radiation Protection and Research
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• v.9 no.2
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• pp.61-66
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• 1984

A study on the characteristics of ${\alpha}$-particle track on cellulose nitrate film was carried out with a particular emphasis on the dependence of track diameter upon chemical etching condition. The track diameters etched in KOH solution appeared to be, on average, three times larger than those etched in NaOH under the same etching condition. The relationship between the track diameters and both etching time and the energy of incident ${\alpha}$-particles was also investigated. It is shown that the particle fluence rate is fairly independent of etching time as far as the condition of irradiation remains unchanged.

• Korean Journal of Microbiology
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• v.6 no.3
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• pp.87-91
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• 1968

To research the characteristics of cellulose produced from one strains of Rhizopus(R-B 14) when it acts on the carboxyl methyl cellulose, this experiment was carried out in crude purified cellulose. The results obtained were as follows: 1. The optimum pH of cellulose was from 4. 5 to 5 .5 and the range of its stability to the pH was considerably extensive and it was from 4 to 7. 2. The optimum temperature of cellulose was $50^{\circ}C$ and the activity of it was instantly inactivated at $70^{\circ}C$. 3. The inhibition of the metal ions to the activity of cellulose was as follows; $Hg^{++}$ > $Ag^+$ +/ > $Fe^{+++}$ > $Pb^{++}$. But the activity of cellulose was not affected at all by $Na^+$, $K^+$ and $Mg^{++}$.

• Textile Coloration and Finishing
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• v.9 no.5
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• pp.30-41
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• 1997

A purpose of this research is to prove unknown relation -ship between finish bath pH and crosslinking. In pursuit of these goals, we have treated 100% cotton broad cloth with PTCA and BTCA at different pH values. They were used with H$_{3}$PO$_{4}$, NaH$_{2}$PO$_{2}$, NaH$_{2}$PO$_{4}$, Na$_{2}$HPO$_{4}$, Na$_{3}$PO$_{4}$, catalysts to produce nonformaldehyde fabrics finishes. Treatments were applied to all cotton fabrics using a parletry-cure process. For the fully understood on the relationship of finish bath pH effect and cotton cellulose esterification, the relative concentrations of chemical species were calculated from ionization constants. The effect of pH on the cotton cellulose ester was investigated using Fourier transform infrared spectra, the surface area measurement by BET method and wrinkle recovery analysis. Results of differential FT-IR spectra and their relative concentration analysis were compared with those of catalyst treated controls. FT-IR and wrinkle recovery data indicated that the esterfication by polycarboxylic acids is pridependent. A similar phenomenon also occurred when a phosphate or hypophosphite was used. Therefore, it is necessary to choose the optimum pH range of a finishing bath in order to achieve the most effective esterification.