• 한국도로학회논문집
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• 제19권6호
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• pp.57-66
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• 2017

PURPOSES : This study develops eco-friendly asphalt reinforcement materials applicable to bridge deck pavement. The main purpose is to ensure highly reliable quality applicable to structures and the possibility of practical application. The main target of the study is to develop materials that are environmentally friendly and capable of improving performance. METHODS : The application of double-reinforcement fiber improves the performance of the road pavement. 1. We use recycled film for application of sheet-typed reinforcement. 2. We use preprocessing fibers to reinforce the properties of composite pavement materials. RESULTS : The developed products may produce materials that fit the purpose of achieving stability and environmental friendliness. Sheet-typed reinforcements use more than 50% recycled resin. The most important type of damage to the asphalt layer is deflection (plastic deformation). These products have a very high deflection resistance of not less than 6,000 cycles/mm. In addition, all performance is excellent. Thus, it will be easier to access the field in the future. CONCLUSIONS : Fiber-reinforced asphalt pavement showed excellent performance. Sheet-typed reinforcements containing 50% recycling resin produced good performance in terms of functionality as well as environmental friendliness. Thus, enhancing the field applicability will enhance the usability of the reinforcements.

• 펄프종이기술
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• 제44권4호
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• pp.25-31
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• 2012

Ionic trash in furnish decreases retention and drainage performance of the microparticle retention system using recycled fibers in closed papermaking system. Two retention systems, such as the microparticle system and the PEO/cofactor system, were compared and analyzed to improve retention. The PEO/cofactor system achieved similar retention performance at low addition level as the microparticle system. Optimum ratio of PEO/cofactor dual polymer system was 1:10. Ash retention was increased when using the fixing agent. As the TMP ratio increased, the PEO/cofactor system was more efficient in retention and drainage than the other system. The high molecular weight and non-ionic polymer retention system had less effect on flocculation hindrance than the traditional electrostatic retention system.

• 펄프종이기술
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• 제48권2호
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• pp.56-60
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• 2016

Neutral or alkaline papermaking provides many advantages in paper strength and processing conditions. It also provides the opportunity of using calcium carbonate fillers in papermaking. These diverse advantages have made almost all paper machines of printing and writing papers run under neutral and alkaline conditions. On the other hand, linerboard machines, which use recycled papers as a raw material, are running under acid conditions using a rosin sizing system. Because the recycled raw materials used by the linerboard industry contain significant amounts of alkaline papers, the linerboard industry has an interest in the possibility of using the neutral or alkaline papermaking opportunity. In this study, the compatibility of the recycled linerboards under neutral or alkaline papermaking conditions was examined by recycling them under various pH conditions. The sizing degree of the papers recycled under neutral or alkaline was significantly lower than that of acid formed papers indicating that during the neutral or alkaline recycling process the rosin sized papers lost their sizing efficiency. Recycling of acid formed linerboards under neutral or alkaline conditions increased the amount of foam, and the foam contained substantial amount of solid materials derived from the acid sizing systems. Use of cationic polyelectrolytes including PEI and poly-DADMAC improved the sizing degree of the recycled papers under neutral and alkaline conditions. PEI decreased the foam generation as well while poly-DADMAC did not show any reducing effect of the foam. These results suggest that PEI forms coordinate bonds with rosin acid and precipitate them onto the surface of recycled fibers, while the reaction products between poly-DADMAC and rosin acid ions still remain water soluble under neutral or alkaline conditions.

• Journal of the Korean Wood Science and Technology
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• 제31권3호
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• pp.1-10
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• 2003

Shredded waste newspapers, waste acrylic raw fibers, and urea-formaldehyde (UF) adhesives, at 10% by weight on raw material, were used to produce recycled waste paper-waste acrylic raw fiber composite boards in laboratory scale experiments. The physical and mechanical properties of fire retardant treated recycled waste paper-waste acrylic raw fiber composite boards were examined to investigate the possibility of using the composites as internal finishing materials with specific gravities of 0.8 and 1.0, containing 5, 10, 20, and 30(wt.%) of waste acrylic raw fiber and 10, 15, 20, and 25(wt.%) of fire retardant (inorganic chemical, FR-7^®) using the fabricating method used by commercial fiberboard manufacturers. The bending modulus of rupture increased as board density increased, decreased as waste acrylic raw fiber content increased, and also decreased as the fire retardant content increased. Mechanical properties were a little inferior to medium density fiberboard (MDF) or hardboard (HB), but significantly superior to gypsum board (GB) and insulation board (IB). The incombustibility of the fire retardant treated composite board increased on increasing the fire retardant content. The study shows that there is a possibility that composites made of recycled waste paper and waste acrylic raw fiber can be use as fire retardant internal finishing materials.

• 한국건설순환자원학회논문집
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• 제3권1호
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• pp.84-89
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• 2015

현무암섬유는 높은 인장강도와 콘크리트와 유사한 밀도를 갖기 때문에 콘크리트 보강 섬유로서 장점을 갖고 있다. 이 연구에서는 현무암섬유의 부착 특성과 섬유 배향각에 따른 현무암섬유의 인장 강도 특성을 조사하였다. 이를 위하여 현무암섬유와 폴리비닐알코올섬유에 대한 섬유 인발 실험을 수행하였고, 현무암, 폴리비닐알코올, 폴리에틸렌섬유에 대하여 섬유 배향각에 따른 인장 강도를 측정하였다. 실험 결과 현무암섬유의 화학적 부착, 마찰 부착, 미끌림 경화 계수는 폴리비닐알코올섬유와 비교하여 각각 1.88, 1.03, 0.24배로 나타났다. 현무암섬유의 배향각에 따른 강도 감소 계수는 폴리비닐알코올섬유의 9배, 폴리에틸렌섬유의 3배로 나타났다.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
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• pp.111-116
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• 2006

The microstickes control effects of some fixing agents, including an inorganic PAC, an organic polyamine (PA) and polydiallydimethyl ammonium chloride (Pdadmac), and a high cationic starch (HCS), were investigated, together with their effects on wet end performances and physical properties of handsheets. Despite that the HCS and Pdadmac had lower cationic charge densities than the PA and PAC (the HCS being even lower), they gave higher zeta potentials to fibers, and lower turbidities, cationic demands and residual COD contents to the pulp liquid phases than the PA and PAC did. In all cases, the HCS showed even better effects than the Pdadmac. In addition, drainage speed was also much higher by the HCS treatments although paper formation was worsened. All the phenomena showed that the HCS can fix more dissolved and colloidal substances to cellulose fibers, indicating that the HCS functioned mainly with flocculation and even hydrogen bonding mechanisms. Data on optical properties further indicated that the HCS interacted preferentially with colloidal substances, since it fixed more 'dirty' microstickes to fibers which decreased more sheet brightness while increasing more sheet opacity (with both higher light absorption and scattering coefficients). Interestingly, the organic fixing agents did not decrease tensile, tearing, and folding strengths of paper sheets made from 100% recycled newsprint pulp, except when they were dosed in high amounts. On the contrary, the inorganic PAC had more serious negative effects on the strength properties, especially on folding endurance. The study suggested that proper use of the HCS can lead to better microstickies control effects than traditional agents and methods.

• 한국건설순환자원학회논문집
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• 제10권3호
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• pp.243-251
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• 2022

이 연구의 목적은 인장강도 및 형상비가 다른 폴리에틸렌 섬유가 무시멘트 복합재료의 인장거동에 미치는 영향을 실험적으로 조사하는 것이다. 이를 위하여 섬유 종류 및 물-결합재비를 달리한 세 가지 배합을 준비하였고, 밀도 실험, 압축강도 실험 및 일축인장 실험을 수행하였다. 실험결과 유사한 화학구조를 갖지만 인장강도가 10 % 낮고, 형상비가 8.3 % 높은 폴리에틸렌 섬유를 사용한 경우 복합재료의 인장변형성능과 인성이 각각 11.7 %와 12.4 % 높고 균열폭은 9.1 % 작은 성능을 나타내었다. 또한 동일한 폴리에틸렌 섬유를 사용한 경우 물-결합재비가 증가하여 복합재료의 강도가 낮지만 인장변형성능과 균열패턴이 향상될 수 있는 것으로 나타났다.

• 한국구조물진단유지관리공학회 논문집
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• 제21권2호
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• pp.122-129
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• 2017

본 연구의 목적은 순환골재를 대량 사용하기 위한 것이다. 천연골재를 순환골재로 50% 치환한 보의 전단성능을 증진시키기 위하여 강섬유를 보강하였다. 강섬유 혼입율은 0%, 0.5%, 0.75% 및 1.0%이다. 실험 결과, 강섬유 혼입율 0.5%인 경우와 0.75%인 경우의 강도 및 변형능력이 비보강 대비 월등히 증진됨을 확인할 수 있었다. 기존 연구자의 전단강도식으로 실험체의 강도를 평가한 결과, Oh et al.(2008)의 전단강도식이 SFRC 보의 전단강도를 안전측으로 예측할 수 있는 것으로 평가되었다.

• 한국건설순환자원학회논문집
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• 제4권3호
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• pp.82-89
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• 2009

최근 국내에서는 건설생산현장에서 순환골재 및 이를 활용한 순환골재 콘크리트의 사용을 적극적으로 도모하기 위하여 순환골재 콘크리트의 제조기술에 관한 다양한 연구개발이 활발하게 이루어지고 있으나 순환굵은 골재에 비하여 순환잔골재에 관한 적용 및 연구는 미흡한 실정이다. 따라서 본 연구에서는 순환잔골재를 사용한 환경부하저감형 콘크리트의 공학적 성능 및 수축균열저감 성능 향상을 위한 섬유보강 순환잔골재 콘크리트의 공학적 특성 및 수축균열특성에 관하여 실험 실증적으로 비교 검토함으로써 향후 환경부하 저감형 섬유보강 순환잔골재 콘크리트의 개발을 위한 기초자료를 제시하고자 한다. 그 결과, 천연잔골재에 비해 순환잔골재의 사용으로 콘크리트의 균열면적이 증가하였으며, W/C비가 증가할수록 균열면적도 증가하는 것으로 나타났다. 또한 섬유종류중 PVA 및 Nylon섬유를 혼입한 시험체의 균열면적이 가장 적은 것으로 나타났으며, 섬유혼입율이 증가할수록 균열면적이 감소하는 것으로 나타나 섬유혼입에 의한 균열저감성능을 확인할 수 있었다.

• 펄프종이기술
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• 제47권6호
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• pp.22-40
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• 2015

Cellulose fibers is one of the most abundant in nature. It has many distinctive features: abundant in nature, biodegradable, non-toxic, eco-friendly, sustainable, easy to fabricate, hydrophilic, and cost-effective. Cellulose fibers, known as pulp, is produced from cellulose-containing materials by the pulping process. As the raw material, wood has been most commonly used while recycled pulp has been also used to some degree. Thus, pulp usually refers to wood pulp. Generally, the pulp and paper industry is regarded as the commodity market where the cost should be much more important than the quality. It also belongs to a mature market where the growth is slow, or even in decline. Accordingly, technological development has been rather stagnant for the industry. Recently, however, the pulp and paper industry has faced very serious challenges. First, due to digital technology, there has been a steady decline in the need for pulp and paper products. The digital industry has continuously replaced printed products such as books, newspapers, and magazines. Second, there has been a trend initiated by developed countries to limit the use of wood as the raw material for the sake of environmental protection. This forces the industry to find a more efficient use of wood pulp as well as finding alternative, non-wood sources. Third, as an individual becomes wealthier and more conscious of health-care, the quality of a product becomes more important than the cost. Thus, a paradigm shift is needed from the cost-conscientious to the quality conscientious. The objective of this article is to review the technologies aimed at engineering cellulose fibers for producing high-value added paper products.