• Journal of the Korean Society of Safety
• /
• v.27 no.5
• /
• pp.117-125
• /
• 2012

In recent years, polymer concrete based on polyester resin have been widely generalized and the research of polymer concrete have been actively pursued by the technical innovations. Polymer concrete is a composite consisting of aggregates and an organic resin binder that hardens by polymerization. Polymer concrete are stronger by a factor of three or more in compression, a factor of four to six in tension and flexural and a factor of two in impact when compared with portland cement concrete. In view of the growing use of polymer concrete, it is important to study the physical characteristics of the material, emphasizing the short term properties as well as long term mechanical behavior. If polymer concrete is to be used in flexural load-bearing application such as in beam, it is imperative to understand the deformation of the material under sustained loading conditions. This study is proposed to empirical and mechanical model of polymer concrete tension creep using long-term experimental results and mathematical development. The test results showed that proposed model has been used successfully to predict creep deformations at a stress level that was 20 percent of the ultimate strength and viscoelastic behavior of recycled-PET polymer concrete is linear of stress level up to 30 percent. It is expected that the present model allows more realistic evaluation of varying stresses in polymer concrete structures with a constant loading.

• Journal of the Korea Concrete Institute
• /
• v.14 no.3
• /
• pp.402-408
• /
• 2002

The permeable polymer-modified concrete has a lot of internal voids, which has more excellent performance in permeability and durability than asphalt and cement concrete. Therefore, the purpose of this study is to ascertain the strength properties of water-permeable polymer concretes with SBR latex and redispersible polymer powder. The water-permeable polymer concretes using SBR latex and redispersible polymer powder with water-binder ratio of 29 ％, polymer-cement ratios of 0, 5, 10, 15 and 20 ％ are prepared, and tested for compressive strength, splitting tensile strength, flexural strength, water permeablility. From the test results, improvements in the strength properties of the water-permeable polymer concretes due to the addition of the SBR latex and redispersible polymer powder are discussed.

• International Journal of Highway Engineering
• /
• v.4 no.4 s.14
• /
• pp.53-66
• /
• 2002

Asphalt binder characteristics in asphalt mixture are changed due to aging. However. depending upon aggregate and binder used, asphalt mixture dose not show the same level of stiffness and brittleness under the same ageing level. The factors affecting Physical Properties change of the asphalt binder within aged asphalt concrete are not well known and there is limited study which is dealing with this topic This study dealt with evaluation of physical properties of asphalt binder recovered from the mixtures after short-term and long-term aging. Two asphalts. two aggregates. two gradations and four polymers were used to make 32 mixture combinations. The mixtures were prepared and aged artificially in a forced draft oven. The measured physical properties included absolute viscosity, kinematic viscosity and penetration. Statistical analyses were carried out to find out the factor(s) having a significant effect on change of physical property of asphalt binder due to asphalt mixture aging. The results of study shown that aggregate, gradation and polymer had a significant effect on change of physical properties of asphalt binder.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 1998.10a
• /
• pp.136-141
• /
• 1998

While a little research has been peformed on flexural behavior of reinforced polymer concrete (RPC)beams with the compressive strength lower than 900kg/$\textrm{cm}^2$ vary little exists in conjunction with the behavior of RPC 1,000kg/$\textrm{cm}^2$ or higher in compressive strength. In this paper the flexural performance of high strength polymer concrete beams with 1,450kg/$\textrm{cm}^2$ in compressive strength was evaluated. The unsaturated polyester resin was used to make polymer concrete as binder. The beams with stirrup singly/doubly were tested to examine the effect of tensile reinforcement ratio. As test results, reinforcement ratio increased with the increase moment strength, decreased with ultimate deflection, ductility index.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2005.11a
• /
• pp.559-562
• /
• 2005

The purpose of this study is to evaluate the durability and bond strength of polymer powder-modified mortars with special accelerator components. The mortars were prepared with various polymer-binder ratios and applied to the concrete substrate as a repair material. Bond strength, flexural and compressive strengths, freeze-thaw resistance and carbonation resistance were measured for the test. As a result, bond strength of the mortars was increased with an increase in the polymer-cement ratio, and freeze-thaw resistance and carbonation resistance were significantly improved with increasing polymer-cement ratio also.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2002.08a
• /
• pp.989-993
• /
• 2002

Barrier ribs in the color plasma display panel(PDP) function to maintain the discharge space between to glass plates as well as to prevent optical crosstalk. Patterning of barrier ribs is one of unique processes for making PDP. In this work photosensitive barrier rib pastes were prepared by incorporating binder polymer, solvent, functional monomers photoinitiator, mid barrier rib powder. Study on the function of materials for the barrier rib paste were undertaken. After optimization of paste formulation, both photolithographic and transparent soft molding method resulted in fine pattern of barrier ribs with high aspect ratio.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.29 no.4
• /
• pp.28-35
• /
• 1997

Sole-binder formulation has been recently introduced to solve the problems of coating process and printability caused by use of natural polymer However, the decrease of natural polymer application causes another problem in paper coating. Therefore, synthetic thickener is used to get similar effect to natural polymer usage. In this study. low shear viscosity, dewatering of coating colors were measured to evaluate the performance of the alkali sensitive water retention and rheology modifiers. The effects of alkali sensitive thickener on the physical properties of coated paper and printability were also investigated. The gloss and printability of coated paper containing the synthetic flow modifier were similar or superior to those of CMC containing coated paper. This modifier was also effective to improve the problems caused by the use of starch. The results indicated that the flow modifier synthesized with alkali sensitive thickener can reduce the problems of natural polymer and could be a good substitute f3r a natural polymer.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.7 no.2 s.17
• /
• pp.100-108
• /
• 2004

Nitramine-polymer composites suffer from a problem known as dewetting. Dewetting adversely affects the performance and the sensitivity characteristics of an explosive composition. Voids, which are generated between explosive particles and binder on dewetting, act as initiation sites. For a PBXs as well as propellants, where good adhesion and mechanical properties are of great importance, dewetting therefore must be prevented by strong adhesion between the filler and the binder. The surface energy of materials is measured by Wilhelmy plate and wicking method. The interfacial energy between the filler and the binder is calculated from the disperse phase and the polar phase of surface energy. Time dependent compressive properties of composite explosives have been determined by stress-strain curves obtained at different strain rates and temperatures. The interfacial state of the PBX was observed through SEM. It was found from the result that the interface between the explosive and the binder becomes better adhesion with decreasing interfacial tension and increasing work of adhesion. The result clearly shows that the castable PBX has good adhesion more than the pressable PBX.

• Journal of the Korean Ceramic Society
• /
• v.37 no.1
• /
• pp.26-32
• /
• 2000

Preparation and characteristics of a matrix retaining electrolyte using SiC whisker, PES binder, and NMP(n-methyl-2-pyrrolidone) as a non-volatile solvent for a phosphoric acid fuel cell were investigated. The conditions of binder and plasticizer, and the effects of substituting a volatile solvent by a non-volatile solvent were also studied. The minimum amount of the binder was about 17 wt% for the proper bubble pressure and surrounding SiC whiskers. And the maximum amount of the plasticizer was about 10wt% to be fitted into the polymer chain of the binder. The matrix prepared by using a non-volatile solvent needed longer time to dry, and its pore size was smaller compared with that of the matrix prepared by using volatile solvent. The small pore size resulted in decrease of the overall pore volume. The ionic conductivity in the condition of the same thickness was decreased due to decrease of phosphoric acid absorbancy. As the internal resistance of the electrolyte increased, the fuel cell performance slightly decreased.

• Journal of Electrochemical Science and Technology
• /
• v.10 no.2
• /
• pp.131-138
• /
• 2019

To improve the performance of Si anodes in advanced Li-ion batteries, the design of the electrode plays a critical role, especially due to the large volumetric expansion in the Si anode during Li insertion. In our study, we used a simple fabrication method to prepare Si-based electrodes by grafting polyacrylic acid (PAA) to a carboxymethyl cellulose (CMC) binder (CMC-g-PAA). The procedure consists of first mixing nano-sized Si and the binders (CMC and PAA), and then coating the slurry on a Cu foil. The carbon network was formed via carbonization of the binders i.e., by a simple heat treatment of the electrode. The carbon network in the electrode is mechanically and electrically robust, which leads to higher electrical conductivity and better mechanical property. This explains its long cycle performance without the addition of a conducting agent (for example, carbon). Therefore, the partially carbonized CMC-g-PAA binder presented in this study represents a new feasible approach to produce Si anodes for use in advanced Li-ion batteries.