• Macromolecular Research
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• 제11권5호
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• pp.347-351
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• 2003

The hydrophobic ligand-containing hollow polypropylene (PP) membranes were synthesized by the mutual radiation induced graft copolymerization with glycidylmethacrylate (GMA) onto hollow PP membrane followed by the subsequent functionalization with L-phenylalanine. FT-IR, elemental analysis and UV spectroscopy were utilized to characterize copolymer composition, and degree of grafting, functionalization conversion and ${\gamma}$-globulins adsorption. The degree of grafting on the PP surface increased with the reaction time and total dose of E-beam. In the subsquent functionalization, the amount of L-phenylalanine increased with the increase in the degree of grafting and the degree of conversion was about 30%. The ${\gamma}$-globulins adsorption experiments showed that adsorption capacity had a maximum value at pH 8. The ${\gamma}$-globulins adsorption capacity in the basic pH region was higher than in the acidic pH region.

• 한국염색가공학회지
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• 제16권5호
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• pp.35-41
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• 2004

Poly(ethylene terephthalate), polyimide(Kapton), and polypropylene surfaces were modified with argon low temperature plasma by RF glow discharge at 240m Torr, 40W to investigate the surface morphological changes due to the plasma treatment using atomic force microscopy(AFM). Analysis of the AFM images and Ra(average roughness) revealed that the plasma treatment resulted in significant ablation on the surfaces. The morphological changes and surface roughness, however, were different depending on material characteristics such as heat stability, presence of amorphous region, swelling phenomenon, and molecular structure of repeating unit. It was assumed that polypropylene due to its tertiary hydrogen was ablated easily compared to poly(ethylene terephthalate), and that polyimide was more resistant to the ablation than PET due to rigid skeleton of imide and stable phenyl ring structure.

• 유변학
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• 제10권2호
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• pp.57-64
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• 1998

A pultrusion resin impregnation (PRI) die, which has been developed recently in our laboratory, was used to pre-pare various composite system. The continuous fiber reinforced composites of glass fiber/polypropylene(GFPP) and glass fiber/polyamide 6 (GFPA) were first manufactured by means of the PRI die and then cut into chopped pellets of predet-ermined length. These pellets and either virgin or modified thermoplastic resin were melt-mixed by a twin screw extruder to prepare GF/PA/PP and GF/PA/PPMA system. The mechanical properties of these blends were investigated and discussed in terms of their morphological observations. These preliminary results revealed that this new impregnation die could be suc-cessfully applied to produce prepregs suitavle for the final shaping process.

• 접착 및 계면
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• 제14권4호
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• pp.192-196
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• 2013

본 연구에서는 polypropylene (PP)을 기본 고분자로 하여, 석유수지(hydrocarbon resin, HCR) 종류와 함량을 달리하여PP/HCR 블랜드의 열량 거동을 분석하였고, 이를 이용하여 bi-axially oriented polypropylene (BOPP) 필름을 제조한 후 필름의 기계적 물성, 광학적 특성, 가스 및 수증기에 대한 투과도 그리고 수축률을 비교 평가하였다. 이 연구에서 HCR로는 수첨 dicyclopentadiene (DCPD) 수지와 수첨 C9 수지가 사용되었다. Homo-PP 대비 PP/HCR 블랜드는 stiffness의 증가 등 필름의 기계적 물성 증가, 필름의 haze 감소 등의 광학적 특성 향상, 가스 및 수증기에 대한 투과도 감소 그리고 필름의 수축률이 증가되었으며, HCR로 사용된 수첨DCPD수지와 수첨 C9수지는 기계적 물성 및 광학적 물성에서는 유사한 기여도를 보이지만, 가스 및 수증기에 대한 투과도와 필름의 수축률에 있어서는 차이를 보였다.

• 공업화학
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• 제10권3호
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• pp.477-485
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• 1999

방사선 전조사법에 의하여 폴리프로필렌 부직포 상에 2,3-에폭시프로필메타크릴레이트 (GMA)를 공중합시킨 후 다양한 혼합용매 상에서 이미노디아세트산 (IDA)과 반응시킴으로서 고성능의 섬유상 금속 흡착제를 제조하였다. 그라프트 반응시의 그라프트율은 반응시간과 반응온도, 총 조사선량 및 선량율에 의존하는 것으로 나타났다. GMA가 그라프트된 폴리프로필렌 부직포 상에 이미노디아세트산을 도입하는 아민화반응에 있어서 다양한 혼합용매가 반응성에 미치는 영향을 고찰한 결과 디메틸술폭시드 (DMSO)와 물을 적정비율로 혼합한 혼합용매 상에서 가장 높은 반응성을 가지는 것으로 나타났으며, 물만을 사용하는 경우 아민화반응은 전혀 진행되지 않았다. 이온농도 100 ppm으로 조재된 중금속 용액에 제조된 아민화 흡착제를 일정시간 담그어 금속이온에 대한 흡착성능을 살펴보았는데, 각각의 경우에 대하여 흡착효율을 다음의 순서를 따랐다: 납>코발트>철.

• 폴리머
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• 제38권3호
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• pp.327-332
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• 2014

고분자/목분 복합재료는 경제적이고 친환경적이기 때문에 최근 많은 관심을 끌고 있다. 본 연구에서는 목분의 크기가 폴리프로필렌/목분 복합재료의 열적, 기계적 특성에 미치는 영향을 조사하였다. 용융혼합 및 압축성형에 의해 제조된 복합재료 샘플의 기계적 특성을 조사하기 위해 만능재료시험기와 아이조드 충격시험기를 사용하였고, 열적 특성을 조사하기 위해 TGA, DMA, DSC 및 TMA를 사용하였다. 말레산 무수물로 개질된 폴리프로필렌 커플링 제 3종을 테스트하여 최적의 커플링제를 선정하였으며 동일조건 하에서 목분의 크기가 복합재료의 물성에 미치는 영향을 살펴보았다. 600, 250, 180, $150{\mu}m$의 네 가지 목분 크기에 대해 실험한 결과 목분의 크기가 작을수록 복합재료의 굴곡강도, 굴곡탄성률, 결정화도 및 내수성이 증가하였다.

• Macromolecular Research
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• 제17권6호
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• pp.378-387
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• 2009

This research compared three methods for producing and processing nanocomposite polypropylene filament yarns with permanent antimicrobial efficiency. The three methods used to mix antimicrobial agents based on silver nano particles with PP were as follows: 1) mixing of PP powder and inorganic nanocomposite filler with the appropriate concentration using a twin-screw extruder and preparing granules, 2) method 1 with a singlerather than twin-screw extruder, and 3) producing the masterbatch by a twin-screw extruder and blending it with PP in the melt spinning process. All pure polypropylene samples and other combined samples had an acceptable spinnability at the spinning temperature of $240^{\circ}C$ and take-up speed of 2,000 m/min. After producing as-spun filament yarns by a pilot plant, melt spinning machine, the samples were drawn, textured and finally weft knitted. The physical and structural properties (e.g., linear density, tenacity, breaking elongation, initial modulus, rupture work, shrinkage and crystallinity) of the as-spun and drawn yarns with constant and variable draw ratios (the variable draw ratio was used to gain a constant breaking elongation of 50%) were investigated and compared, while DSC, SEM and FTIR techniques were used to characterize the samples. Finally, the antibacterial efficiency of the knitted samples was evaluated. The experimental results revealed that the crystallinity reduction of the as-spun yarn obtained from method 1 (5%) was more than that of method 2 (3%), while the crystallinity of the modified as-spun yarns obtained with method 3 remained unchanged compared to pure yarn. However, the drawing procedure compensated for this difference. By applying methods 2 and 3, the drawing generally improved the tenacity and modulus of the modified fibers, whereas method 1 degraded the constant draw ratio. Although the biostatic efficiency of the nanocomposite yarns was excellent with all three methods, the modified fabrics obtained from methods 1 and 2 showed a higher bioactivity.

• 한국식품영양과학회지
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• 제27권6호
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• pp.1137-1142
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• 1998

Modified atmosphere packagings were designed by combining the respiration characteristics of the enoki mushroom at 10oC and the measured film permeabilities to O2 and CO2 gases to attain the beneficial package atmosphere were fabricated and tested during storage. The packages of 100g size with 30 m low density polyethylene and cast polypropylene showed the good agreement between estimated and experimental package atmospheres. However, polyvinylchloride stretch wrap packs showed the gas composition close to the air, which was due to leaking of stretch wrapping. The CPP package attaining O2 below 1% and CO2 concentration of 15~20% gave the best retention of quality and thus the longest shelf life among the tried packages, and it was superior to the others in the Hunter L value, stipe elongation and sensory qualties.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.96-97
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• 2020

Polymer modified cement mortar (PCM) is commonly used as a repair material. However, in high-temperature environments such as fire, it is more likely to explode than cement mortar. The polymer is thermally decomposed at a high temperature to form a gas, and the gas remaining inside the structure increases the internal pressure to generate a burst. When an spalling occurs, the coating is peeled off and dropped, and high temperature is transmitted to the inside of the structure. In severe cases, even the reinforcing bar is exposed, which can lead to the collapse of the structural member due to severe loss of strength. In this study, in order to reduce spalling of PCM, a fiber mixing method was selected from the refractory method to find an appropriate blending ratio of fibers and polymers.

• Macromolecular Research
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• 제16권1호
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• pp.21-30
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• 2008

Based on the sheath-core bicomponent composite fibers with modified polystyrene (PS) and the modified polypropylene (PP), composite fibers obtained were further cross-linked and sulphonated with chlorosulphonic acid to produce strong acidic cation ion exchange fibers. The structures of the fibers obtained were characterized using Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC) etc. The optimal technology of the fibers obtained is discussed. The static absorption capacity of the sheath-core bicomponent composite cation exchange fibers for $Zn^{2+}$, $Cu^{2+}$ was determined. The absorption kinetics and major factors affecting the absorption capacities of $Zn^{2+}$, $Cu^{2+}$ were studied, and its chemical stability and regenerating properties were probed. The results suggest that cation exchange fibers with better mechanical properties and higher exchange capability were obtained. Moreover, this type of ion exchange fiber has good absorption properties and working stability to various metal ions. Hence, they have higher practicability.