• Journal of the Korean Ceramic Society
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• v.36 no.5
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• pp.539-546
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• 1999

Absorbent polymer-cement composites were fabricated by the semi-powder mixing OPC(ordinary Portland cement) with an absorbent polymer. The effects of absorbent polymer on the mechanical properties and the hydration characteristics were observed and the polymer-cement interaction also discussed. Absorbent polymer-cement composites showed the value of total porosity of 8vol% the value of 28 days flexural strength was up to 280 Kgf/cm2 in the case of absorbent polymer-cement composite at 1 wt% absorbent polymer content and microstructure of absorbent polymer-cement composite has been observed more dense than that of OPC paste. Accordingly the permeability of compositewas improved and so the moisture resistance was also increased. Adding polymer did not retard the hydration of OPC. It was considered from the results of IR(infrared) analysis that the functional group of absorbent polymer would be changed from unidentate to bidentate during by the hydration of cement minerals.

• Elastomers and Composites
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• v.47 no.2
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• pp.141-147
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• 2012

Silicone resin has no water-absorbing function because it is a strong hydrophobic polymer. However, addition of super absorbent polymer gives much better absorbency than that of conventional silicone resin. In this study, we developed novel silicone materials with water-absorbing function by choosing three types of amorphous acrylic super absorbent polymers with different particle sizes, determining the mixing ratio of the three polymers and applying the mixtures into two-component type silicone material for medical purpose. The change in the mechanical properties such as tensile strength, tear strength, compressive strength and hardness was investigated by varying the particle size and content ratio of the added super absorbent polymers while preparing the silicone resins. The absorbency of the silicone resins was measured over time. Additionally, the particle shape of the super absorbent polymers as well as the distribution within the silicone resin was observed using an optical microscope.

• Journal of the Korean Wood Science and Technology
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• v.18 no.2
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• pp.36-48
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• 1990

This experiment was carried out to improve the quality of high absorbent polymer which has excellent absorptivity and water retention compared to pulp and absorption sheet, through absorption characteristics-absorptive power, water retention, absorption rate, gel strength, pH, particle size, and moisture content. - of six polymers, namely, anionic polyacrylamide, cationic polyacrylamide, polyacrylic, acid polyvinyle alcohol 500, and 1500, and a-cellulose. and to examine the possibility of substitution of amide groups for carboxyl group and/or hydroxyl group which were commercial high absorbent polymer by comparing the absorption characteristics of the polymers. Polyacrylamide has high absorptive power and water retention, but has low gel strength and poor absorption rate. The rest of polymers were similiar to ${\alpha}$-cellulose in every respect. Thus, polyacrylamides could be replaced with polyacrylic acid and polyvinyl alcohol which are presently a high absorbent polymers. In comparing the absorption characteristics and the absorptive power of the polymers-anionic polyacrylamide, cationic polyacrylamide, polyacrylic acid, polyvinyle alcohol. a-cellulose-the absorptive power was in inverse proportion to the gel strength and absorption rates, affected by the particle size and pH change.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.775-777
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• 2003

Several methods are available for the fabrication of electrode pattern for the plasma display panel(PDP) including screen printing and photolithographic method. Piezo type ink-jet printing method is considered to the method of choice for electrode patterning in manufacturing of PDP. Both silver ink and absorbent layer paste formulation were developed for ink-jet printing of electrode pattern. The ink-jet printing of silver electrode with preformed absorbent layer was especially suitable for the patterning of address electrode for high resolution PDP.

• Journal of the Korean Society of Safety
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• v.8 no.1
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• pp.29-34
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• 1993

Two major hazardous gases. SOx and NOx. are emissioned from fossile fuels. SOx has been removed when oil is refined but NOx hasn't. So NOx is very serious problem in air pollution now There are several technologies to remove NOx. e.g. cooling method. scrubbers method. combustion method, polymer membrane method and adsorbent methods. Polymer membrane and adsorbent methods have good economic merit in removal systems of low content hazard gases. Traditional absorbents are porous silicas, aluminas. active carbon and zeolites. But these absorbents act only physisorption which has less removal performance than chemisorption. In this study. polymeric absorbent which has chemisorption as well as physisorption was analyzed about chemical structure and experimented about optimum operation conditions. The results showed that the chemical structure of the polymeric absorbent was expected as polystyrene having -N-CH$_2$COOH absorbent was revealed about 310$m^2$/g. The molar ratio of absored NO to charged NO in absorption experiments was shown 60% of the polymeric absorbent and 45% of zeolite absorbent at 3$0^{\circ}C$.

• Solar Energy
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• v.10 no.2
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• pp.28-37
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• 1990

A study was conducted to investigate the feasibility of using a super-absorbent polymer made from a acrylic acid copolymer for a capsule-type ice storage system. In a simple pyrex-tube test, 25% of distilled water samples tested turned out not be frozen at all at $-12^{\circ}C$ and the average supercooling of the samples frozen was $9.8^{\circ}C$. With the addition of 0.5wt% super-absorbent polymer, however, the supercooling of the distilled water was dramatically reduced and more than 35% of samples tested did not show any supercooling. The heat transfer characteristics of a capsule-type ice storage unit was also investigated with a distilled water as the phase-change material. With the addition of 0.5wt% polymer, the supercooling of water was not observed at all and thus an overall heat transfer was enhanced. Based on these results, it was concluded that a super-absorbent polymer is a potential candidate as the nucleating agent for an ice-storage system.

• Journal of Microbiology and Biotechnology
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• v.30 no.9
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• pp.1310-1320
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• 2020

Low-quality soil for land reuse is a crucial problem in vegetation quality and especially to waste disposal sites in mining areas. It is necessary to find suitable materials to improve the soil quality and especially to increase soil microbial diversity and activity. In this study, pot experiments were conducted to investigate the effect of a mixed material of humic acid, super absorbent polymer and biochar on low-quality soil indexes and the microbial community response. The indexes included soil physicochemical properties and the corresponding plant growth. The results showed that the mixed material could improve chemical properties and physical structure of soil by increasing the bulk density, porosity, macro aggregate, and promote the mineralization of nutrient elements in soil. The best performance was achieved by adding 3 g·kg^-1 super absorbent polymer, 3 g·kg^-1 humic acid, and 10 g·kg^-1 biochar to soil with plant total nitrogen, dry weight and height increased by 85.18%, 266.41% and 74.06%, respectively. Physicochemical properties caused changes in soil microbial diversity. Acidobacteria, Bacteroidetes, Chloroflexi, Cyanobacteria, Firmicutes, Nitrospirae, Planctomycetes, and Proteobacteria were significantly positively correlated with most of the physical, chemical and plant indicators. Actinobacteria and Armatimonadetes were significantly negatively correlated with most measurement factors. Therefore, this study can contribute to improving the understanding of low-quality soil and how it affects soil microbial functions and sustainability.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.209-209
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• 2006

Ultra-fine fibers are spun by expensive fiber spinning technology using special spinnerets. Ultra-fine fibrous materials have attracted considerable attentions because of their potential applications as high performance wiping cloths, water absorbent sound proofing materials and moisture transfer sporting good. However, production expense of ultra-fine fibers is 5 to 7 times higher than general textile materials. The objective of this research is to develop cost-effective recycling process to produce multi-functional ultra-fine fibrous material in terms of the development of garnetting and carding machines for ultra-fine fibrous material waste and scrap. The efficiency of sound absorption for the recycled polyester nonwoven increased with decreasing length and thickness of component fibers, which was attributed to the reduction of air permeability. It is expected that high value and cost-effective textile products are developed using ultra-fine fibrous wastes and that sound proofing material and oil absorbent f

• Macromolecular Research
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• v.9 no.3
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• pp.143-149
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• 2001

Poly(aspartic acid), PASP, is a biodegradable, water-soluble polymer and offers a biodegradable alternative to polycarboxylates and other non-degradable water-soluble polymers. PASP one of poly (amino acid)s, possesses carboxylic acid pendant group in its repeating unit, which can be used for various further modification purposes. In this study we prepared high molecular weight polysuccinimide, as the precursor polymer for PASP, by thermal polycondensation ofL-aspartic acid in the presence of phosphoric acid. The polysuccinimide was hydrolyzed with 0.1 N sodium hydroxide, and then acidified to give PASP. High water-absorbent gels were produced by thermal crosslinking of freeze-dried mixture of partially-neutralized PASP and different amount of low moi. wt. PEG-diepoxide compounds in aqueous medium. The swelling behavior of the prepared gels from different size and composition of crosslinking reagent in different media was investigated and the results were discussed. This PASP-based hydrogel materials possessing inherent biodegradability, potential non-toxicity and biocompatibility, is expected to be used as a substrate for various biomedical applications as well as a general purpose super-absorbent polymer.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.6
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• pp.20-29
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• 2016

This study investigates the effect of the absorbent materials on the material properties(compressive strength and drying shrinkage) of natural hwangtoh mortar which is one of the traditional building material in Korea. The absorbent materials used are seaweed paste and Super-Absorbent Polymer(SAP). In addition to the absorbent materials, the initial sealed curing recommended by the standard specification of properties for Korean traditional building materials is also a main interest of this study. Based on the test results of 28 days compressive strength and converged drying shrinkage, it is confirmed that the initial sealed curing for 7 days is effective to reduce the drying shrinkage and to enhance the compressive strength. Thus, it is verified that the recommendation is reasonable and has positive effects on the properties of the mortar. Next, the test results show that the addition of absorbent materials into the mortar is also effective to the two properties depending on their absorption capacity. Thus, it is more effective to use SAP than the seaweed paste because of higher absorption capacity. However, both the initial sealed curing and keeping total water contents of the mortar are required to show this effectiveness. Lastly, the compressive strength is inversely proportional to the drying shrinkage. By using this relation, the reason of the increase of compressive strength due to the initial sealed curing or the addition of absorbent materials is quantitatively explained.