• 한국안전학회지
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• 제22권5호
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• pp.77-83
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• 2007

식물류에 다량으로 함유되어 있는 Cellulose는 인체에 무해할 뿐 아니라 연소시에 발생하는 유해가스가 적어서 친환경적인 에너지 자원으로 대두되고 있다. 특히 Cellulose의 유도체 중 하나인 Hydroxypropyl Methyl Cellulose(HMC)는 의약품의 코팅재료를 비롯하여, 고급용 건축자재, 염료, 화장품 등의 첨가제로 사용되면서, 사용량이 계속해서 증가하고 있다. 따라서 여러 가지 위험에 노출될 수 있으며, 열적 위험특성을 알기 위한 방법으로 일본에서 많이 사용되고 있는 단열자기발열실험장치(SIT-II)를 이용하여 HMC의 한계발화온도와 겉보기활성화에너지를 구하였다. 또한 국제적으로 널리 알려진 Frank-Kamenetskii의 무한평판을 기준으로 한 자연발화실험(IF-SIT)자료를 이용하여 자연발화온도와 활성화 에너지 값을 비교하였다. HMC의 자연발화온도와 겉보기 활성화 에너지는 SIT-II의 경우 $186^{\circ}C$의 한계발화온도와 104.5kJ/mol의 활성화 에너지를 구하였다. 기존에 구하여진 IF-SIT결과 값과 비교하였을 때 무한평판의 두께 3cm, 5cm, 7cm에 대해 각각 한계발화온도가 $199.5^{\circ}C,\;188.5^{\circ}C,\;180.5^{\circ}C$이고, 167.4kJ/mol의 활성화 에너지 값을 지니므로, SIT-II로 구하여진 겉보기 활성화 에너지는 IF-SIT로 구하여진 값 보다 낮게 나타났으며, 이 값은 일반 Cellulose의 활성화 에너지 값 보다 도 더 낮은 것으로 나타났다.

• 분석과학
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• 제7권3호
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• pp.271-276
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• 1994

셀룰로스에 대한 +2와 +3가 금속이온들의 흡착성을 최적 조건에서 실험하였는데, +2가 금속이온으로 Cu(II), Zn(II), Pb(II) 및 Cd(II) 이온을 선택하였으며, +3가 금속이온으로 Cr(III)와 Fe(III) 이온을 선택하여 실험하였다. 셀룰로스에 대한 흡착능을 증대시키기 위하여 셀룰로스를 2M NaOH로 처리하여 Na-셀룰로스를 제소하였다. 셀룰로스에 대한 금속이온 흡착능은 매우 작아서 고분자 흡착제로서의 효과가 없었으나 Na-셀룰로스는 고분자 흡착제로서 매우 효과적이었다. Na-셀룰로스에 대한 금속이온들의 흡착은 뱃치법으로 실험하였다. 최적 조건에서 Na-셀룰로스에 대한 금속이온들의 흡착은 +2가 금속이온들은 1:2, +3가 금속이온들은 1:3의 흡착비로 흡착하는 이온교환 흡착이었다. Na-셀룰로스에 대한 금속이온들의 흡착엔탈피는 -18kcal/mol 정도였으며, carboxymethylcellulose(CMC)와 Dowex 50W-X8 수지와 비교 실험한 결과, Na-셀룰로스에 대한 금속이온들은 흡착은 이온교환흡착으로, 비슷한 작용기를 가지고 있는 CMC와 비슷한 흡착엔탈피를 보였다.

• 한국잠사곤충학회지
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• 제19권1호
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• pp.9-13
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• 1977

누에의 인공사료에 첨가하는 cellulose의 종류별 제제방법별 및 첨가량별로 사육시험을 행한 결과를 요약하면 다음과 같다. 1. 공시한 cellulose 중에서는 뽕나무 cellulos가 잠체중과 견층비율이 높고 감잠비율은 낮으며 경과일수도 짧아서 가장 우수하고 그 다음이 소나무 cellulose로서 뽕나무 cellulose와 거의 비슷한 사육성적을 나타내었다. 2. Cellulose조제방법은 PA법이나 NaOH처리법이나 서로 비슷한 사육성적을 나타내었으며 cellulose원에 따른 차이도 거의 인정되지 않았으나 무처리 cellulose는 극히 불량하였다. 3. 인공사료에 첨가하는 cellulose의 양은 건물사료의 15∼22.5%범위가 적당한 것으로 나타났다.

• Fibers and Polymers
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• 제6권2호
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• pp.95-102
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• 2005

Sodium cellulose carbonate (CC-Na) dissolved in $8.5\;wt\%$ NaOH/ZnO (100/2-3, w/w) aqueous solution was spun into some acidic coagulant systems. Diameter of regenerated cellulose fibers obtained was in the range of $15-50\;{\mu}m$. Serrated or circular cross sectional views were obtained by controlling salt concentration or acidity in the acid/salt/water coagulant systems. Velocity ratio of take-up to spinning was controlled up to 4/1 with increasing spinning velocity from 5 to 40 m/min. Skin structure of was developed at lower acidity or higher concentration of coagulants. Fineness, tenacity and elongation of the regenerated cellulose fibers were in the range of 1.5-27 denier, 1.2-2.2 g/d, and $8-11.3\;\%$, respectively. All of CC-Na and cellulose fibers spun from CC-Na exhibited cellulose II crystalline structure. Crystallinity index was increased with increasing take-up speed.

• 한국염색가공학회지
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• 제4권3호
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• pp.91-96
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• 1992

The crystalline character of NaOH and KOH-cellulose complex having different tension ratio was studied using X-ray diffraction analysis. Cellulose crystalline lattices in tension alkali treatment cotton were identified by measuring and indexing the 101, 101, and 002 reflections. According as alkali treatment tension ratio increased on, cellulose gave rise to the formation of I rather than cellulose II. It seemed that a part of the fine structure of cellulose increased orientation with antiparaell and parallel chain crystal structure. The high tension ratio alkali treatment cotton resulted in lower dye sorption and in higher breaking strength and crease recovery.

• 펄프종이기술
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• 제41권4호
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• pp.58-64
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• 2009

This study was carried out to prepare high porosity pulp for oil and air filter media from commercial grade NBKP with 6 - 20% NaOH treatment. The fiber width of NBKP remarkably decreased by NaOH pretreatment. The air permeability of the test sheet prepared from alkali-pretreated NBKP increased with increasing NaOH concentration up to 15%. The burst factor was greatly decreased by alkali pretreatment. By 15 - 20% NaOH pretreatment of NBKP, it could be possible to prepare a high porosity pulp. It seems that the high porosity of the pulp was due to a strong swelling and a great change of the cellulose crystalline lattice from cellulose I to cellulose II with NaOH treatment of NBKP. The study suggested that alkali- pretreated NBKP could be used for manufacturing oil and air filter media.

• 한국염색가공학회지
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• 제7권2호
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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.

• 한국의류학회지
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• 제18권1호
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• pp.15-22
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• 1994

본 연구에서는 면시험포와 cellophane film을 이용하여 xenon arc lamp 를 사용한 인공기후조 안에서 광선의 파장에 따른 강도의 변화와 변색을 조사하였다. Pyrex와 quartz filter를 사용하여 광선의 파장이 섬유의 성질을 변화시키는 중요한 요인임을 밝히고 first-order kinetic model을 사용하여 반응속도를 측정하였다. 또 면섬유의 황변현상을 화학적으로분석하여 파장이 긴 자외선과 가시광선의 영역에서는 황변과 동시에 표백효과가 있음을 알게 되었고 그 속도를 측정하였다. 세가지의 중요한 말단기분석을 통해 carbonyl기의 양이 제일 많고 carboxyl기와 peroxide기도 존재함을 분석하였고 또 이들의 양은 온도와 습도에 따라 변화하는 것으로 나타났다 Cellulose chain의 중합도를 측정하고 이를 cellulose bond scission과 연결시켜서 중합도와 섬유의 강도저하와의 관계를 연구하였다.

• Journal of the Korean Wood Science and Technology
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• 제20권1호
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• pp.38-45
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• 1992

Fine and alkali-swollen structures of native cellulose fibers were investigated by x-ray diffraction methods. The results of fine structures are shown in Table 1. In meridional x-ray diffractograms, the relative intensity ratio R of (002) to (004) for cellulose I was ca. 0.05 and for regenerated cellulose it was ca. 0.45. It was considered that the transformation from cellulose I to cellulose II resulted from the packing or conformational change of cellulose chain. Finally. although cellulose I was not detected in the alkali-swollen celluloses treated for 1 hr to 24 hrs, washing and drying them resulted in the generation of considerable amounts of cellulose I and the amount decreased with increasing alkali duration.

• Journal of Periodontal and Implant Science
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• 제24권1호
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• pp.51-63
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• 1994

There has been many attempts to develop a method that can regenerate periodontal tissues that were lost due to periodontal diseasd, but none of them was completely successful. This study was designed to investigate the healing and regeneration of periodontal tissue when bone substitutes such as porous replamineform hydroxyapatite and porous resorbable calcium carbonate were used in combination with oxidized cellulose membrane and collagen absorbable hemostat, compared to a control where only oxidized cellulose membrane or collagen absorbable hemostat were used. Chronic periodontitis was induced on mandibular premolars of and adult dog by placing orthodontic elastic ligatures for 10 weeks. After flap operation, the control group were received oxidized cellulose membrane (control- I )or collagen absorbable hemostat (control- II) only, while one experimental group was given either porous replamineform hydroxyapatite or porous resorbable calcium carbonate in addition to oxidized cellulose membrane (Experimental I-A, I-B), and another experimental group was treated by using either porous replamineform hydroxyapatite or porous resorbable calcium carbonate in addition to collagen absorbable hemostat. (Experimental II-A, II-B) After 56 weeks, healing was histologically analyzed with the following results. 1. Apical migration of junctional epithelium was observed only in areas coronal to the notch for both control and experimental group. 2. Inflammatory cell infiltration was not observed in any groups. 3. Oxidized cellulose membrane and collagen absorbable hemostat were completely resorbed. 4. Newly-formed cementum was observed up to the level where junctional epithelium was located, for both control and experimental groups. 5. Bone formation was limited of the middle portion of the notch in the control group, where as experimental groups showed bone formation up to the level of implant materials coronal to the notch. 6. Minute resorption of apically located portions of implanted materials was observed in experimental group I-B and II-B only.