• 펄프종이기술
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• 제48권2호
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• pp.83-90
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• 2016

Increasing the amount of filler in paper is of high interest for paper industry while maintaining its key sheet quality properties. In this study, a MFC-GCC composite, made through a co-grinding NBSK (Northern bleached softwood kraft) pulp with a ground calcium carbonate (Intracarb 60), was used as a strength aid in paper in order to evaluate a potential cost reduction through filler increase without sacrificing paper quality. Hand-sheets were made of NBSK and/or eucalyptus pulp by using white water recirculation in a Tappi sheet former and was compared its properties without or with MFC additions at different filler levels. It was found that the MFC-GCC composite has a large surface area compared to the fiber, allowing the formation of more hydrogen bonds in the web, thus giving natural strength to the paper. Overall results are encouraging that the MFC-GCC composite allows papermaker to reduce basis weight and maintain critical sheet properties.

• 펄프종이기술
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• 제47권2호
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• pp.61-69
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• 2015

A number of researches have been carried out regarding the utilization of nanocellulose(crystalline nanocellulose, microfibrillated cellulose, nanofibrillated cellulose) for the manufacture of various kinds of composites and functional products. However, only few research works on the manufacturing characteristics of nanocellulose could be found, although some companies started already the production of nanocellulose in commercial scale. However, the most important thing in commercializing of production and utilization of nanocellulose is to develop the economical and efficient process. Thus, this study was carried out in order to investigate the effects of refining, alkaline pre-treatment and grinder clearance on the characteristics of microfibrillated cellulose and energy consumption. There was no significant differences in crystalline index with the degree of microfibrillation. The initial fibrillation could be improved by refining pre-treatment, but its effect was not observed anymore since the fibrillation was done up to certain level by grinding. Refining pre-treatment did not improved the energy efficiency. Alkaline pre-treatment can be helpful because the swelling of pulp fiber will facilitate fibrillation. It was found that the decrease in grinder clearance was helpful to improve the energy efficiency.

• Journal of Microbiology and Biotechnology
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• 제32권12호
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• pp.1589-1598
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• 2022

Microfibrillated cellulose (MFC) is a valuable material with wide industrial applications, particularly for the food and cosmetics industries, owing to its excellent physiochemical properties. Here, we prepared high-solid microfibrillated cellulose (HMFC) from the centrifugation of Gelidium amansiiderived MFC right after fibrillation. Dispersion properties, morphology, and structural changes were monitored during processing. HMFC has a five-fold higher solid concentration than MFC without significant changes to dispersion properties. SEM images and FTIR spectra of HMFC revealed a stable surface and structure against centrifugal forces. HMFC exhibited 2,2'-azino-bis (3-ethylbenzothiazoline6-sulfonic acid) (ABTS) radical scavenging activity, although it could not scavenge 2,2-diphenyl-1- picrylhydrazyl (DPPH). Moreover, HMFC inhibited the generation of LPS-induced excessive nitrite and radial oxygen species in murine macrophage RAW264.7 cells. Additionally, HMFC suppressed LPS-induced Keap-1 expression in the cytosol but did not alter iNOS expression. HMFC also attenuated the UVB-induced phosphorylation of p38, c-Jun N-terminal kinase (JNK) 1/2, and extracellular-signal-regulated kinase (ERK) 1/2, as well as the phosphorylation of c-Jun in the immortalized human skin keratinocyte HaCaT cells. Therefore, the application of centrifugation is suitable for producing high-solid MFC as a candidate material for anti-inflammatory and antioxidative marine cosmeceuticals.

• 한국포장학회지
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• 제29권2호
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• pp.103-110
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• 2023

The study aimed to enhance the properties of polylactic acid (PLA), a biodegradable and biocompatible substitute for fossil-based plastics. Since the applicability of PLA has been limited because of its toughness and brittleness, microfibrillated cellulose (MFC) and propolis were introduced into PLA. As a result, the PLA film with MFC/propolis showed significant improvements in mechanical strength, elongation, and storage modulus, while also experiencing a decrease in the glass transition temperature. Additionally, the presence of polyphenols in propolis led to a reduction in light transmittance in the UV wavelength range. These enhancements are attributed to MFC tightly bonding with PLA polymers, and propolis acting as a plasticizer and mediator between MFC and PLA, preventing agglomeration. These reinforced PLA films have the potential to be used in flexible packaging for light-sensitive products.

• 펄프종이기술
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• 제47권6호
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• pp.57-65
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• 2015

Microfibrillated cellulose (MFC) or Nanofibrillated cellulose (NFC) has been used to reduce the use of raw pulp and to improve paper strength. The problem of MFC preparation is high manufacturing cost. In this study, it was carried out to prepare MFC after enzyme beating and estimated properties of MFC. Endo-D was the best beating efficiency among three type of endo-glucanase. As the grinder pass number increased, the viscosity and the fines of MFC suspension increased while the crystallinity and the porosity of MFC sheet decreased. Also enzyme beating MFC was higher value in the crystallinity and lower value in the viscosity than non-enzyme MFC. In addition, the aspect ratio of MFC was the highest at 5 pass. MFC addition improved the handsheet strength and the air permeability but worsened the drainage.

• Journal of the Korean Wood Science and Technology
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• 제42권4호
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• pp.483-490
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• 2014

마이크로피브릴 셀룰로오스(MFC) 강화 polybutylene succinate (PBS) 나노복합재료의 성질에 미치는 MFC 첨가량 및 커플링제로서 polymeric methylene diphenyl diisocyanate (pMDI)의 첨가 영향을 조사하였다. 나노복합재료의 인장강도 및 탄성율은 MFC의 첨가량이 증가함에 따라 향상되었다. 또한 pMDI 첨가에 의하여 인장강도 및 탄성율은 증가하였으며, MFC첨가량이 증가하면서 그 경향이 더욱 뚜렷하였다. PBS/MFC (70/30) 복합재료에서는 인장강도가 pMDI(1 중량부)의 첨가에 의하여 약 1.5배 이상 향상되었다. 이러한 향상은 pMDI 첨가에 의한 MFC의 분산성 및 메트릭스 고분자와의 계면접착성 향상에 기인하며, 전자현미경을 이용한 파단면 관찰로 확인하였다. 또한, pMDI 첨가에 의하여 나노복합재료의 열적 안정성도 향상되었다.

• 한국미생물·생명공학회지
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• 제45권1호
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• pp.1-11
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• 2017

본 논문에서는 나노셀룰로오스의 일종으로 최근 가장 주목을 받고 있는 소재인 마이크로피브릴화 셀룰로오스에 대하여 살펴보았다. 마이크로피브릴화 셀룰로오스는 리그노셀룰로오스계 바이오매스의 셀룰로오스에서 유래한 섬유로 풍부하고, 재생가능하며, 지속 가능한 천연 소재의 일종이다. 주로 물리적 전처리에 의해 생성되며, 나노미터에서 마이크로미터에 이르는 다양한 소섬유들의 결합으로 이루어져 있다. 이로 인해 마이크로피브릴화 셀룰로오스는 높은 표면적과, 높은 aspect ratio, 그리고 특이적인 용해성을 가지게 되고, 이는 전통적인 목재 산업 뿐만 아니라, 최신식의 식품/바이오/화학/의료 산업에 이르는 다양한 영역에의 적용 가능성을 보여주는 주요한 원인이 된다. 한편 이러한 응용력에도 불구하고, 아직 마이크로피브릴화 셀룰로오스는 제조 시 필요한 높은 에너지량과 반응성 조절의 어려움 때문에 상업적으로 많은 주목을 받지 못하고 있다. 따라서, 마이크로피브릴화 셀룰로오스의 기질에 대한 특성을 이해 및 구체화하고, 마이크로피브릴화 셀룰로오스의 피브릴화도를 선택하며, 표면의 개량을 선택적으로 조절할 수 있는 시스템을 개발하는 연구가 필요할 것이다. 마이크로피브릴화 셀룰로오스가 향후 우리나라의 산업 전반에 걸쳐 활용될 수 있기를 기대해 본다.

• 펄프종이기술
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• 제48권1호
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• pp.5-18
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• 2016

Electron microscopy is an important investigation and analytical method for the morphological characterization of various cellulosic materials, such as micro-crystalline cellulose (MCC), microfibrillated cellulose (MFC), nanofibrillated cellulose (NFC), and cellulose nanocrystals (CNC). However, more accurate morphological analysis requires high-quality micrographs acquired from the proper use of an electron microscope and associated sample preparation methods. Understanding the interaction of electron and matter as well as the importance of sample preparation methods, including drying and staining methods, enables the production of high quality images with adequate information on the nanocellulosic materials. This paper provides a brief overview of the micro and nano structural analysis of cellulose, as investigated using transmission and scanning electron microscopy.

• 폴리머
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• 제38권1호
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• pp.74-79
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• 2014

두 가지 서로 다른 실란 화합물인 3-aminopropyltriethoxysilane(APS)과 3-mercaptopropyltriethoxysilane(MRPS) 그리고 lauroyl chloride를 이용하여 마이크로피브릴화 셀룰로오스(MFC) 표면을 화학적으로 개질하였다. 화학적으로 표면 처리한 MFC의 구조 및 특성은 FTIR, EDX, TGA, 접촉각 등을 측정하여 분석하였다. 이렇게 유기 관능기로 치환된 MFC와 폴리아마이드(PA) 섬유를 사용하여 복합 페이퍼를 제조하였다. MFC의 표면 개질은 MFC 사이의 응집을 막아줄 뿐만 아니라 PA 섬유와의 접착성을 향상시켜 주는 역할을 한다. 단섬유인 PA 섬유를 연결시켜주는 바인더 역할을 하는 MFC 없이는 페이퍼를 제조할 수가 없었다. 즉, 표면 개질된 MFC는 PA 섬유 내에서 분산되어 PA 섬유들을 연결시켜 복합페이퍼의 제조를 가능하게 하였다. 두 가지 실란 화합물로 개질된 MFC를 이용한 복합페이퍼의 인장강도와 인장탄성률의 기계적 물성은 lauroyl 그룹으로 치환된 MFC를 이용한 복합페이퍼에 비하여 우수하였다. 화학적으로 표면 처리한 MFC와 PA 섬유로 제조된 복합페이퍼의 모폴로지와 기계적 물성은 SEM과 UTM을 통하여 분석하였다.

• Journal of the Korean Wood Science and Technology
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• 제43권1호
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• pp.17-24
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• 2015

본 연구에서는 잣나무 목분의 탈리그닌 정도가 습식디스크밀을 이용한 해섬처리의 효율에 미치는 영향과 얻어진 해섬물의 성질을 조사하였다. 또한, 탈리그닌 정도가 종이의 인장강도 특성에 미치는 영향도 조사하였다. 탈리그닌의 정도는 아염소산나트륨과 초산을 사용하는 Wise법의 처리횟수를 달리함으로서 조절하였다. 탈리그닌 정도가 증가함에 따라 해섬효율은 향상되었으며, 디스크밀 처리횟수가 증가함으로서 섬유직경은 감소, 여수시간은 증가하였다. 또한 종이의 인장강도 및 탄성률도 탈리그닌 정도 및 디스크밀 처리횟수가 증가할수록 증가하였다.