• Polymer Science and Technology
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• v.26 no.2
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• pp.149-154
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• 2015

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11a
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• pp.24-29
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• 1999

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2007.11a
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• pp.103-108
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• 2007

• Polymer Science and Technology
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• v.23 no.6
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• pp.598-607
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• 2012

• Environmental Engineering Research
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• v.22 no.3
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• pp.255-265
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• 2017

Polyelectrolytes are commonly used as flocculants in drinking water treatment. However the growing concerns about their toxicity have motivated the search for biocompatible flocculants. Here, we show that gelatin, a natural amphoteric polyelectrolyte, can be effectively adsorbed on clay surfaces and can potentially be a suitable substitute for existing flocculants. The adsorption of gelatin from its aqueous solution onto the mineral clay surfaces at different conditions was systematically investigated using the design of experiments methodology. The gelatin adsorption was found to vary considerately with pH variation showed a maximum adsorption at its isoelectric point. The amount of adsorbed gelation increased with increasing pH from 3 to 5, attained a maximum at pH 5 and then decreased with increasing pH from 5 to 11. Similarly, the amount of adsorbed gelatin showed decreasing trends around salt concentration of 0.05 M and temperature $35^{\circ}C$. On the other hand, the adsorption was continuously increased with time and polymer concentration in the range of 0.1-0.9 mg/dL. Finally, the jar tests confirmed the ability of gelatin for using a natural flocculant for water treatment.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.4
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• pp.71-77
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• 2010

To utilize modified pulp fibers in papermaking system, it is necessary to evaluate the interaction between modified fibers and papermaking additives. Fluorescent whitening agent (FWA) is an important additive which has been widely used for production of writing and printing paper. We modified pulp fiber surface by Layer-by-Layer multilayering of polyelectrolytes, and investigated the interaction between these fibers and FWA used in internal addition or surface treatment. Pulp fiber with cationic surface charge showed a good affinity to internal FWA. For FWA in surface sizing agent, whiteness and brightness of paper was dependent on pickup weight and polyelectrolyte type. Pulp fibers with C-starch/PSS multilayer showed better optical properties than poly-DADMAC/PSS treatment. It indicated that polyelectrolyte type in Layer-by-Layer multilayering as well as a good affinity to FWA is important to get better whiteness and brightness.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.6
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• pp.78-86
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• 2014

Since cellulose nanofibrils (CNF) has large specific surface area and high water holding capacity, it is very difficult task to remove water from the CNF suspension. However, dewatering of CNF suspension is a prerequisite of following processes such as mat forming and drying for the application of CNF. In this study, we evaluated the drainage of cellulose fibers suspension under vacuum and pressure conditions depending on the number of grinding passes. Also, the effect of the addition of cationic polyelectrolyte on dewatering ability of CNF suspension was investigated. Regardless of dewatering condition, the total drained water amount as well as the drainage rate were decreased with an increase in the number of grinding passes. Pressure dewatering equipment enables us to prepare wet CNF mat with relatively higher grammage. The cationic polyelectrolytes improved the dewatering ability of CNF suspension by controlling the zeta potential of CNF. The fast drainage was obtained when CNF suspension had around neutral zeta potential.

• Journal of Environmental Science International
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• v.11 no.2
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• pp.93-102
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• 2002

Using a simple continuous optical technique, coupled with measurements of zeta potential, the flocculation characteristics of kaoline suspensions of different content(15, 35 and 55 NTU) by several cationic polyelectrolytes, has been examined. The optimum mixing is obtained under a constant stirring of 200 rpm, differently from a general flocculation test. The charge density of a polyelectrolyte is important in determining the optimum dosage and in the removal of kaoline particles. The optimum dosage is less for the polyelectrolyte of higher charge density and is the same regardless of kaoline content. At the dosage, the removal of kaoline particles is higher for the polyelectrolyte of higher charge density and zeta potential of kaoline particles reaches to near zero. The rate of adsorption and flocculation rate have been found to be affected by charge density and molecular weight of a polyelelctrolyte and the content of kaoline particles.

• Journal of Environmental Health Sciences
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• v.30 no.3
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• pp.253-258
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• 2004

Synthetic organic polyelectrolytes can be used to condition sludges to enhance their dewaterability. Intermittent aerobic digestion is an useful digestion technology and has many advantages like neutral pH, low installation cost and easiness to operation. The objectives of this study were to investigate the dewaterability of intemittent aerobic digestion sludge and to find the relationship between dewaterability and particle size distribution change under the conditioning of intermittent aerobic digestion sludge by cationic polyelectrolyte. Digested sludge from intermittent aerobic digestion was used and cationic polyacrylamide polymer was added as a conditioner. CST(capillary suction time), TTF(time-to-filtration) were tested as a dewaterability index and the number of particle distribution was analyzed using particle size analyzer. The results indicate that cationic polyelectrolytes is useful to enhance dewaterability of intermittent aerobic digestion sludge. Mean particle diameter was increased as polymer dosage increased and its value was reached up to 100 mm on the condition of optimal cationic polymer dosage. CST and TTF are well correlated with mean particle diameter when the weighting order is 1.7. By the optimal conditioning with cationic polymer, particles in the filtrate are also reduced significantly and this means that conditioning is helpful to main stream by reducing SS loading from return flow.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.1 s.60
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• pp.1-6
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• 2007

It has been generally known that liposomes become unstable when they contain cyclodextrins (CDs). Our present studies demonstrate that these liposomes can be stable by association of amphiphilic polyelectrolytes. Transmission electron microscopy and photocorrelation spectroscopy results showed that polymer-associated liposomes containing CDs (${\beta}-CD$(${\beta}CD$) and hydroxypropyl-${\beta}CD$ ($HP{\beta}CD$)) were more stable than phosphatidylcholine (PC)-cholesterol (Chol) liposomes containing these CDs. We also compared the stability of PC-Chol liposomes with polymer-associated liposomes containing $HP{\beta}CD$ complexed with water-insoluble drug, rhaponticin (Rh). Two liposomes were relatively stable when $HP{\beta}CD$ did not contain Rh, but Rh-$HP{\beta}CD$ complexes triggered the disruption of PC-Chol liposomes. In contrast, polymer-associated Liposomes containing Rh-$HP{\beta}CD$ complexes maintained its stability over 6 months. The skin permeation test demonstrated that drugs solubilized by CDs were delivered better into the skin of guinea pig by using polymer-associated liposomes than by using PC-Chol liposomes. Above results showed that polymer-associated liposomes gave an effective way to stabilize the liposomes containing drug-loaded CDs, which gives an application of liposomes in drug delivery systems.