• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.209-213
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• 2006

Relationship between printability and rheological properties of UV flexographic (flexo) inks were investigated. UV flexo suspensions of carbon black in liquid medium having various binding materials such as acylate pre-polymer, di/multi-functional monomer, and diluents, were used as sample inks. Inks were characterized on a rheometer in terms of steady and dynamic behaviors. To understand the rheological properties of UV flexo inks, we must determine the specific rheological properties of chemical and/or physical interactions of their components (pigments, functional monomers, and pre-polymers). In particular, we discussed the influence of multi-functional monomers and the relationship between the rheological properties and transient networks formed by carbon black. In this study, we investigated the interrelationships between rheological properties of UV flexo inks and chemical and/or physical interactions of their components. To investigate correlations between the printability and the rheological behaviors induced by interfacial interactions between ink compositions, we carried out rheological tests of UV ink suspensions. The results were compared with printing tests so as to find out the relationship between printability and rheological properties of ink.

• Polymer(Korea)
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• v.33 no.4
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• pp.384-388
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• 2009

The rheological properties of poly (acrylonitrile) (PAN) and cellulose acetate (CA) blend solutions in N,N-dimethyl formamide (DMF) were investigated in terms of temperature and blend composition. The solutions exhibited a very characteristic rheological behavior with variation of temperature. 8 wt% solution showed an increase of viscosity and a decrease of loss tangent as temperature was increased over the temperature range of 20 and $60^{\circ}C$. At $20^{\circ}C$ the physical properties of the solutions exhibited dependence on the blend composition. At 40 and $60^{\circ}C$, however, the effects of blend ratio on the physical properties notably diminished. The longer relaxation time at higher temperature indicated that the formation of physical structures resulting from intermolecular interactions was promoted with increasing temperature. The odd rheological responses were further elucidated by measuring of the physical properties of dilute solutions. The intrinsic viscosity of the solutions suggested that the coiled chain dimension was reduced with increasing temperature.

• Preventive Nutrition and Food Science
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• v.8 no.4
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• pp.419-424
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• 2003

The physical properties of food playa significant role in the modeling and computation of the heat and mass transfers in basic food processing operations. With the advent of improved analytical techniques, statistical experiment design applications, computing ability and knowledge of the food physical properties of food, there have been significant advances in our ability to predict the impact of processing on the physical properties of food. This article briefly reviews our current ability to predict the influence of processing on the physical properties of food, such as water activity, moisture, color, and rheological characteristics.

• Food Science of Animal Resources
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• v.42 no.5
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• pp.889-902
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• 2022

With increasing consumer demand for "clean label" products, the use of natural ingredients is required in the food industry. Protein/polysaccharide complexes are considered good alternatives to synthetic emulsifiers and stabilizers for formulating stable emulsion-based foods. Milk protein and carrageenan are widely used to improve the physical properties and stability of dairy food products. In a previous study, milk protein isolate (MPI) was conjugated with 𝛋-carrageenan (𝛋-Car) in a wet-heating system through the Maillard reaction, and the Maillard conjugates (MC) derived from MPI and 𝛋-Car effectively improved the stability of oil-in-water emulsions. Therefore, MPI/𝛋-Car conjugates were used in whipping cream as natural emulsifiers in this study, and the physical and rheological properties of whipping creams stabilized using MPI/𝛋-Car MC and MPI/𝛋-Car electrostatic complexes (EC) were investigated. The whipping creams stabilized with MPI/𝛋-Car MC have lower rheological parameters (η_a,50, K, G', and G'') than those of whipping creams stabilized with MPI/𝛋-Car EC. Although the overrun value was slightly reduced owing to the addition of MPI/𝛋-Car MC, the stability of the whipped creams with MC was effectively improved due to enhanced water-holding ability by conjugation.

• Macromolecular Research
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• v.17 no.12
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• pp.950-955
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• 2009

The physical and rheological properties of thermoplasticized irradiation-crosslinked polyethylene foam using supercritical methanol treatment were investigated by GPC, FTIR, DSC, WAXS, DMTA and UDS. The polyethylene foam was selectively decrosslinked into thermoplasticized polyethylene in an appropriate supercritical methanol condition without any undesirable side reactions such as oxidation and disproportionation. The thermoplasticization was promoted with increasing reaction temperature to reach completion above $380^{\circ}C$. The supercritical reaction condition affected the crystallization behavior, and mechanical and rheological properties of the decrosslinked polyethylene foam, but not its crystallographic structure or crystallinity.

• The Korean Journal of Community Living Science
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• v.26 no.1
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• pp.135-143
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• 2015

This study investigates the rheological properties of bread containing lotus leaf powder, added to the bread bases at 1%, 2%, and 3% concentrations. Physical properties of bread with lotus leaf powder were tested using the rapid viscoanalyzer (RVA), a farinogram, an alveogram, and a rheofermentometer. The initial pasting temperature increased with an increase in lotus leaf powder, whereas peak viscosity and, the peak time decreased. According to the farinogram test, consistency and water absorption increased with an increase in the ratio of lotus leaf powder. The p value of the alveogram increased with an increase in lotus leaf powder, whereas L and G values decreased. The fermentation time of the dough increased with an increase in the ratio of lotus leaf powder. The results suggest the potential development of bread containing functional ingredient such as lotus leaf powder based on the rheological properties identified in this study.

• Korea-Australia Rheology Journal
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• v.20 no.4
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• pp.213-220
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• 2008

The effects of temperature on the rheological properties of the solutions of poly(vinylidene fluoride-co-hexafluopropylene) (PVDF-HFP) in dimethyl acetamide (DMAc) were investigated in terms of frequency and concentration. The effects of temperature on the intrinsic viscosity of the solutions were discussed. In dynamic rheological measurement, the concentrated solutions showed a little unexpected rheological response; as temperature was increased dynamic viscosity was increased and the solutions exhibited more noticeable Bingham body character over the temperature range, 30 to $70^{\circ}C$. In addition, the solution gave longer relaxation time, lower value of loss tangent and higher value of yield stress at higher temperature and at higher concentration. On the other hand, the dilute solutions revealed that intrinsic viscosity was decreased and its Huggins constant was increased with increasing temperature. These physical parameters suggested that the increase of viscosity with increasing temperature resulted from the localized gelation of PVDF-HFP due to reduced solubility to the solvent.

• Korea-Australia Rheology Journal
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• v.17 no.2
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• pp.79-85
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• 2005

Aqueous mixtures of hyaluronic acid and poly(vinyl alcohol) system and hydrogels thereof were introduced to obtain new bioartificial materials that have excellent mechanical properties, biocompatibility and enhanced rheological properties. The interactions between hyaluronic acid and poly(vinyl alcohol) and/or borax were investigated by rheological measurements. Preparation parameters of the aqueous mixtures were mixture composition, the degree of hydrolysis of poly(vinyl alcohol) and borax concentration. From the rheological behavior, it could be deduced that the key factor of the interaction between hyaluronic acid and poly(vinyl alcohol) was the hydrogen bonding between them and the effect was pronounced with borax. Enhanced viscosity was observed at the composition of $20wt\%$ of hyaluronic acid solution and $80wt\%$ of poly(vinyl alcohol) and borax solution. Rheological properties were influenced by the degree of hydrolysis of poly(vinyl alcohol) and borax concentration. As the degree of hydrolysis and borax concentration increased, rheological properties increased due to the increased hydrogen bonding and networking of hyaluronate aggregates. Physical hydrogels from hyaluronic acid and poly(vinyl alcohol) were prepared and the composition dependence of the gels was rheologically investigated as well.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.219-219
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• 2006

This study focuses on the effects of dispersion method of a nanoparticle in a polymer matrix such as melt mixing, solution blending, and in-situ polymerization on the physical properties of the nanocomposites. Introduction of a nanoparticle to a polymer resulted in some unusual physical properties. In some cases the nanoparticle played a role of a nucleating agent, leading to decreasing induction time to crystallization. In addition, the dispersion state of the nanoparticle in the polymer matrix also had a significant influence on the physical properties of the nanocomposites. Hence the method of introducing the nanoparticle to the polymer made contribution to the rheological properties of the nanocomposite systems.

• Journal of the Korean Home Economics Association
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• v.23 no.1
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• pp.33-47
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• 1985

The rheological properties of acorn starch gel were investigated in region of small and large deformation. The properties were compared with those of potato and wheat starch gel. On the physical characteristics and the effect of tannin contents of acorn starch were examined. RESULTS : 1. X-ray diffractogram of acorn starch showed C-type and its granules swelled gradully with heating. 2. Hardness, brittleness and both small and large deformation of the acorn starch gel were remarkably large, also the concentration dependence of the acorn starch gel could be recognized in small deformation and hardness. 3. The Young's modulus of Hookean body in small deformation and the rupture stress in large deformation differed obviously from the parameters of rheological properties in various gels. 4. It was found that the selling power, viscosity and rhelogical properties were affected obviously by the tannin.