• Journal of Biomedical Engineering Research
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• v.39 no.4
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• pp.161-167
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• 2018

Polyvinyl alcohol/sodium carboxymethyl cellulose (PVA/NaCMC) hydrogels were prepared by physical crosslinking (cyclic freezing/thawing) and gamma (${\gamma}$)-ray irradiation to evaluate the effect of NaCMC concentration (2~8 wt%) on the mechanical properties and the biocompatibility of the PVA/NaCMC hydrogels. The swelling rate of PVA/NaCMC hydrogels regardless of irradiation rose with increasing NaCMC content from 2 wt% to 8 wt%, while the gelation rate was the reverse. As the NaCMC content increased from 2 wt% to 6 wt%, the compressive strength of the hydrogels increased dramatically from $8.5{\pm}2.0kPa$ to $52.7{\pm}2.5kPa$ before irradiation and from $13.5{\pm}2.9kPa$ to $65.5{\pm}8.7kPa$ after irradiation. When 8 wt% NaCMC was added afterwards, the compressive strength decreased however. The irradiated PVA/NaCMC hydrogels containing 6 wt% NaCMC exhibited the tailored properties of the swelling rate of $118{\pm}3.7%$, the gelation rate of $71.4{\pm}1.3%$, the strength of $65.5{\pm}8.7kPa$, respectively, and no cytotoxicity was observed.

• Journal of the Korean Society of Clothing and Textiles
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• v.18 no.1
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• pp.113-120
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• 1994

The Purpose of this study was to improve the moisture related properties of viscose rayon fibers. Viscose rayon filament yarns were partially etherified to make CMC fibers. CMC fibers were converted to the sodium, calcium, and ferric salt forms by an ion exchange method. The property changes of ion exchanged CMC fibers were examined. Cation contents of fibers were varied depending on the degree of substitution of CMC fibers. The strength of Na, Ca, Fe-CMC was higher than H-CMC owing to the plasticization by moisture sorption and the crosslinking by cations. The moisture regain was increased by carboxymethylation and that of Fe-CMC showed the highest value. The degree of swelling determined by the water retention value was observed to be Na-CMC > Ca-CMC > H-CMC > Fe-CMC. The solution retention value was decreased in the order . Ca-CMC > Na-CMC > H-CMC > Fe-CMC.

• Journal of Pharmaceutical Investigation
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• v.34 no.6
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• pp.477-482
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• 2004

The aim of the present study was to investigate the efficacy of a mixed gel formulation composed of sodium carboxymethyl cellulose and gellan gum (Na-CMC gel) for the prevention of adhesions after laminectomy. The anti-adhesive effect of the Na-CMC gel was tested in a controlled randomized study using an animal model of lumbar laminectomy. The animals (60 female Sprague-Dawley rats) were randomly allocated into two treatment groups to receive the Na-CMC gel on the injured area or no gel (control). The incidence of adhesions and their grade were blindly evaluated at 4, 8 and 12 weeks after surgery. The amount of scar tissue and tenacity were grossly reduced by the Na-CMC gel at postoperative 4, 8, and 12 weeks. The mean adhesion scores were 0.75, 1.25, and 1.38 at 4, 8, and 12 weeks in the gel-treated group, respectively. No significant inflammatory reaction was observed and the healing of wound was not affected by the Na-CMC gel. The Na-CMC gel reduced the amount of scar formation and tenacity in rat laminectomy model without affecting the healing of operation wound and other complications. Therefore, the Na-CMC gel may be the potential to prevent postsurgical adhesions in clinical state.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.303-311
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• 1986

This work was designed as basic studies on the development of diet for the treatment of obesity. The effect of alginic acid which is the major component of brown algae was investigated by comparing with agar, cellulose, carboxymethylcellulose (CMC), chitin, and lignin as dietary fibers. These dietary fibers ($10\%$) supplemented to basic diet were fed ad libitum to Sprague Dawley rat for 4 weeks, and the inhibitory effects on obesity were evaluated by measuring body weight gain and feed efficiency, the content of glucose and cholesterol in serum, lipase activity in serum, lipid content in liver, adipose tissue around epididymis and ovarium, and Lee index etc. Among the inhibitory effect of these dietary fibers on obesity, lignin was the most effective (p<0.001), followed by Na-alginate (p<0.01) for body weight gain, but lignin was the most effective, followed by CMC, and followed by Na-alginate for feed efficiency (p<0.001). In the inhibitory effects on lipid accumulation in liver and adipose tissue around epididymis and ovarium, lignin and Na-alginate group among these dietary fibers were more effective than others, but there was no significant difference between male and female. The inhibitory effect on obesity evaluated by Lee index was effective in the order of Na-alginate>lignin>CMC>chitin>cellulose (p<0.001). The decreasing effects of lipid content in liver by dietary fibers were found in the order of agar>CMC>cellulose>Na-alginate>chitin>lignin (p<0.001). Glucose content in serum was significantly decreased in cases of CMC, lignin and Na-alginate, whereas a slight difference was found in chitin, but cholesterol content in serum was decreased for all dietary fibers examined except cellulose group. The increasing effect of lipase activity in plasma was found in cases of Na-alginate and chitin, while cellulose, CMC and lignin groups were decreased.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.4
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• pp.1-7
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• 2003

In this study, fiber mechanical pretreatment before refining was executed with the addition of papermaking addiditives to find synergistic effects on fiber property improvement. Three fiber furnishes (SwBKP, KOCC, and BCTMP), and five different additives (CMC, CPAM, PEO, NaOH, $Na_2O_2$) were used. It was confirmed again that fiber mechanical pretreatment using Hobart mixer was a special way to modify fiber properties, where fiber WRV (water retention value) increases without losing fiber length. For SwBKP, addition of small amount of CMC (0.2％ OD basis), and for KOCC, PEO (0.2％ OD basis) caused additional significant improvement of the fiber furnish properties, respectively. Other additives did not cause adverse effects on the mechanical pretreatment, or better. For BCTMP, NaOH addition followed by mechanical pretreatment caused more than 20％ improvement in tensile and tear strength simultaneously, compared to the control. The yellowing caused by the treatment of NaOH on BCTMP could be minimized by using $Na_2O_2$ without losing the positive effect of NaOH.

• Bulletin of the Korean Chemical Society
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• v.7 no.5
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• pp.399-402
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• 1986

The critical micelle concentration (CMC) of sodium deoxycholate (NaDC) and the effects of amides on the micellization processes have been studied by fluorometric technique using pyrene as a probe. The addition of amides as cosolvent destabilized the NaDC micelle and increased the CMC. The order of effectiveness for the perturbation of NaDC micelle was N-methylacetamide ${\ge}$ DMF > acetamide > formamide, which is the order of hydrophobicity of the amines. This indicated that the effect of amides on the micellization processes of NaDC arises from diminution of the hydrophobic effect. The electrostatic repulsion between ionic head groups in the NaDC micelle appeared to be much less than that in aliphatic ionic micelle. This was also revealed in the weaker dependence of the CMC on ionic strength. The premicellar association of NaDC was not significantly involved in the micellization processes of the bile salt.

• Journal of the Korean Chemical Society
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• v.39 no.12
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• pp.896-901
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• 1995

The critical micelle concentrations(CMC$^*$) of the mixed surfactant systems of Sodium dodecyl sulfate(SDS) with Tetraethylene glycol monododecyl ether(TGME) in the aqueous solutions of NaCl at $25^{\circ}C$ were determined as a function of the overall mole fraction of $SDS(\alpha1)$ by the use of surface tension method. Various thermodynamic parameters for the micellization of SDS/TGME mixed surfactant systems were calculated and analyzed by means of the equations derived from the nonideal mixed micelle model, based on the pseudo-phase separation model.

• Clean Technology
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• v.11 no.2
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• pp.105-116
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• 2005

Carboxymethylcellulose(CMC) which is water soluble at room temperature was manufactured from the cellulose material in this study. Experimental parameters were reaction temperature, time and concentration of NaOH and monochloroacetic acid. CMC was tested for solubility, degree of substitution(D.S.) and tensile strength. The surface structure of CMC fiber was tested using scanning electron microscope(SEM). CMC manufactured from viscose rayon was affected by the chemical concentration rather then the reaction time and temperature. Also, degree of substitution is closely related to the solubility of the CMC.

• Journal of Korea Soil Environment Society
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• v.3 no.1
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• pp.65-74
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• 1998

To enhance the washing efficiency of soil polluted by hydrophobic organic compounds, the effects of electrolytes and monomeric organic additives on micelle formation and washing efficiency of mixed surfactant solutions were investigated in this study. The surface tensions and critical micelle concentrations(CMCs) of the single and mixed surfactant solutions[$POE_5$/SDS] supplemented by NaCl were measured to investigate the effects on washing efficiency, and the composition ratios of surfactants and NaCl were optimized for the efficient soil washing system. As the mixing ratio of $POE_5$/SDS was increased to 80%, the mixed surfactant with 0.01M NaCl showed more proportional increase of washing efficiency than the mixed surfactant without any salts. The 3% solution of $POE_5$ and SDS(80%/2o%) with 0.01M NaCl showed the washing efficiency of 90%. However, the washing efficiency was not enhanced by NaCl addition to the single surfactant solution of $POE_5$. The CMC of SDS(0.049%) was higher than that of $POE_5$(0.016%), but the CMCs of mixed surfactants were decreased as the mixing ratio of $POE_5$ was increased. Alcohols having longer chain and branched carbon chain were found to be desirable for the soil washing additives.

• Horticultural Science & Technology
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• v.16 no.2
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• pp.222-225
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• 1998

The objective of this study was to observe the effects of potassium-carboxymethyl cellulose (K-CMC), which is a natural polymer derivative, and polyacrylamide (PAM), which is a commercial synthetic polymer, on soil physicochemical properties and yields of the cabbage. To increase water absorbing capacity (WAC), hydrophilic carboxymethyl group was introduced to cellulose chain and it was confirmed by FT-IR. WAC was tested by tea-bag method in distilled water and 3% NaCl solution. PAM is slightly more absorptive than K-CMC in distilled water, but in NaCl solution, K-CMC is more absorptive than PAM. Soil particle sizes above $1_{mm}$ were immediately increased from 9.6 to approximately 16.6% by the application of K-CMC and PAM, respectively. Infiltration rates of soil were approximately twice as great as those of the control when conditioned with the K-CMC and PAM treatment. K content of soil treated with K-CMC was significantly higher than those of PAM and control, but the other components of soil chemical properties were not different. The early growth and vegetative production of cabbage in the K-CMC and PAM treatments were significantly higher than the control. The contents of vitamin C were increased with the treatment of K-CMC. It was proposed that K-CMC treatment influence K component of the soil and vitamin C content of the cabbage, therefore, it improved the yields as well as crop quality.