• Textile Coloration and Finishing
• /
• v.27 no.4
• /
• pp.334-339
• /
• 2015

Polyketone fiber, a newly developed high strength fiber, has a tenacity and modulus similar to the paramid fiber, and can be used for reinforcing mechanical rubber goods(MRG), such as tires, hoses, and technical textiles. In addition, aliphatic polyketone, which has excellent strength, modulus, chemical stability and reasonable price, is being developed only in South Korea. It will be expected for replacement of super fiber such as aramids and increasing the technical textile market share. This paper surveys the mechanical properties of polyketone fiber yarn for technical textiles. For this purpose, two kinds of yarns are prepared, mechanical properties of coated and uncoated polyketone yarns such as tensile strength, elongation and modulus were examined before and after weather resistance test(temperature $60^{\circ}C$, humidity 60%, amount of power $0.67w/m^2$). The differences of mechanical properties between uncoated and coated yarns for high functional technical textiles and composite materials are estimated through this study.

• Textile Coloration and Finishing
• /
• v.29 no.2
• /
• pp.97-103
• /
• 2017

Polyketone fiber, a newly developed high strength fiber, has a tenacity and modulus similar to the p-aramid fiber, and can be used for reinforcing mechanical rubber goods(MRG), such as tires, hoses, and technical textiles. It will be expected for replacement of super fiber such as aramids and increasing the technical textile market share. This paper surveys the mechanical properties of polyketone fiber for technical textiles. For this purpose, dyed polyketone fabric is prepared, mechanical properties of coated and uncoated polyketone fabrics such as tensile strength, elongation and tear strength were examined before and after weather resistance test(temperature $63{\pm}3^{\circ}C$, humidity 60%, amount of power $0.35w/m^2$). The differences of mechanical properties between uncoated and coated fabrics for high functional technical textiles and composite materials are estimated through this study. The UV-stability of polyketone fabric showed obvious improvement after coating. After 168h(7day) of UV exposure, the coated fabric showed less deterioration in mechanical properties with the retained tensile strength and elongation at break greater than 22 and 17% of the uncoated polyketone fabrics values, respectively.

• Textile Coloration and Finishing
• /
• v.33 no.3
• /
• pp.153-160
• /
• 2021

In this study, composite materials were prepared by varying the content of glass fiber and bamboo fiber in PP/glass fiber/bamboo fiber. Experiments were conducted to confirm the mechanical properties(tensile, impact and burst strength) and volatile organic compound content of the bamboo fiber composite prepared under these conditions. An improvement in the main properties was observed at a fiber content of 30wt%. When the fiber fraction was increased above 30wt%, the mechanical properties tended to decrease due to the agglomeration of fibers at higher load fractions. In addition, the content of volatile organic compounds increased as the content of bamboo fibers increased, which is thought to be due to the volatile organic compounds generated during the manufacturing process of the composite material being present in the composite material without escaping from the pores of the bamboo fibers and volatilizing at a certain temperature. As a result of confirming the physical properties of the composite, it is considered that the optimal mixing condition is 30wt% of bamboo fiber for the composite produced by varying the amount of bamboo fiber composite. In the future, it is thought that follow-up experiments to confirm and improve the pre-treatment conditions for reducing the content of volatile organic compounds in the manufactured composite material are possible.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2022.11a
• /
• pp.55-56
• /
• 2022

As global warming becomes serious, research is continuously being conducted to reduce CO2 emissions. Among building materials, the carbon emission of cement is so high that it accounts for 6.8% of the carbon emission of the entire industry. Studies replacement of cement with blast furnace slag and fly ash are steadily increasing. In addition, efforts are being made to reduce air pollution due to increased damage caused by increased concentrations of harmful substances such as fine dust and heavy metals in the air. There is an increasing number of studies that enable adsorption by mixing adsorbents into building materials. This study reviewed the strength properties to make an adsorbable non-cement finishing material by mixing tourmaline, an adsorbent, based on the non-cement composite, and confirmed that the strength decreases as the replacement ratio increases.

• The Journal of the Acoustical Society of Korea
• /
• v.21 no.2E
• /
• pp.81-90
• /
• 2002

Single absorbing materials and Helmholtz resonators have limited absorption characteristics over limited frequency ranges due to their structures and properties. Porous materials are highly absorptive for mid and high frequency ranges, while they have little sound absorption for low frequency sounds. Helmholtz resonators are generally used to absorb sound energy for a specified frequency range. Hence they have limited capability in controlling the overall acoustic properties of a space. Not much has been known about useful finishing materials which have enough rigidity and absorption over broad frequency range, in spite of wide demands from acoustic designers and consultants. The present work measured and analyzed absorption characteristics of a slit absorber by varying surface materials, depths of air gap, dimensions of slat and slit widths. It was found that the narrower the slit width, the larger the absorptions over the wide frequency ranges and the pattern was dependent on the presence of porous material. Narrower slat's width tend to increase the slit absorber's absorption more or less. Absorption coefficients at low frequency ranges were dramatically improved (from 0.23 to 0.56) by increasing air gap when porous materials were present.

• Textile Coloration and Finishing
• /
• v.26 no.3
• /
• pp.195-200
• /
• 2014

Poly(vinyl alcohol)(PVA)/pullulan/titanium dioxide($TiO_2$) composite nanofibers were produced at different $TiO_2$ concentrations(1 and 3 wt.%) using the electrospinning method. The parameters of electrospinning including polymer contents, voltage and tip-to-collector distance(TCD) were optimized for fabrication process. The study showed that the best condition to make PVA/pullulan nanofiber and effect of $TiO_2$ nanoparticles. The PVA/pullulan/$TiO_2$ nanofibers were characterized by scanning electron microscope(SEM), transmission electron microscope(TEM), Thermogravimetric analysis (TGA) and X-ray diffraction(XRD).

• Textile Coloration and Finishing
• /
• v.30 no.2
• /
• pp.77-89
• /
• 2018

In the case of fiber/rubber composites for tire applications, the interfacial adhesion between fiber and rubber significantly affects the physical properties of the finished products. Generally, organic synthetic fibers used for tire cords are treated with resorcinol formaldehyde latex(RFL) primer on the surface of the fiber to improve the adhesion to rubber. Changes of adhesion between rubber and tire cords might weaken as temperature rises due to overheating of car engine and friction with road. In this study, the effects of temperature on the primer treated polyketone cord/rubber composites and the changes in interfacial adhesion were investigated. Polyketone cord/rubber composites were prepared after RFL solution treatment on the surface of polyketone fibers. After that, composites was thermally aged at different temperature conditions(60, 80, 100, $120^{\circ}C$) and times(1, 5, 10, 15days). The adhesion strength of polyketone cord/rubber composite treated with RFL primer was higher than untreated composite by more than 3 times. After heat aging, the adhesion strength of untreated polyketone cord/rubber composites increased while the RFL treated polyketone cord/rubber composites decreased somewhat.

• Textile Coloration and Finishing
• /
• v.34 no.2
• /
• pp.109-116
• /
• 2022

Tire codes are made of materials such as hemp, cotton, rayon, nylon, steel, polyester, glass, and aramid are fiber reinforcement materials that go inside rubber to increase durability, driveability, and stability of vehicle tires. The reinforcement of the tire cord may construct a composite material using tires such as automobiles, trucks, aircraft, bicycles, and fibrous materials such as electric belts and hoses as reinforcement materials. Therefore, it is essential to ensure that the adhesive force between the rubber and the reinforced fiber exhibits the desired physical properties in the rubber composite material made of a rubber matrix with reinforced fibers. This study is a study on the heat treatment conditions for improving the adhesion strength of the tire cord and the reinforced fiber for tires. The core technology of the drying process is a uniform drying technology, which has a great influence on the quality of the reinforcement. Therefore, the uniform airflow distribution is determined by the geometry and operating conditions of the dryer. Therefore, this study carried out a numerical analysis of the shape of a drying nozzle for improving the performance of hot air drying in a dryer used for drying the coated reinforced fibers. In addition, the flow characteristics were examined through numerical analysis of the study on the change in the shape of the chamber affecting drying.

• Composites Research
• /
• v.31 no.4
• /
• pp.133-138
• /
• 2018

Polymer foams were used to fill the void in the structure in addition to flame retardant and heat insulation. Polymer foams such as polyurethane, polyisocyanurate, poly(vinyl chloride), polyethylene terephthalate were used to weight lighting materials. In this study, epoxy foam was used to improve mechanical properties of polymer foam. Acid anhydride type hardener reacts with polyol. Using this phenomenon, if blowing agent was added into epoxy resin using acid anhydride type hardener, formation and compressive properties of epoxy foam was studied. Formation of polymer foam was compared with type of blowing agent and concentration of blowing agent via compressive test. As these results, optimized condition of epoxy foam was found and epoxy foam had better compressive property than other polymer foam.

• Composites Research
• /
• v.31 no.4
• /
• pp.122-127
• /
• 2018

Sandwich composites of carbon fiber reinforced plastic(CFRP) and polymer foam will be used to automobile and aerospace industry according to increasing importance of light weight. In this study, mechanical and heat resistance properties of sandwich composites were compared with type of polymer foam (polyethylene terephthalate(PET), polyvinylchloride(PVC), epoxy and polyurethane). All types of polymer foams were degraded to 30, 60, 120, 180 minutes in $180^{\circ}C$. After heat degradation, the polymer foams were observed using optical microscope and compressive test was performed using universal testing machine(UTM). Epoxy foam had the highest compressive property to 2.6 MPa and after thermal degradation, the mechanical property and structure of foam were less changed than others. Epoxy foam had better mechanical properties than other polymer foams under high temperature. Because the epoxy foam was post cured under high temperature. As the results, Epoxy foam was optimal materials to apply to structures that thermal energy was loaded constantly.