펄프 특성이 염화지방산의 기상 그라프트 반응효율에 미치는 영향

서진호(Jin Ho Seo),이태주(Tai Ju Lee),이광섭(Kwang Seob Lee),이동진(Dong Jin Lee),이명구(Myoung Ku Lee),류정용(Jeong Yong Ryu) 한국펄프·종이공학회 2016 펄프.종이기술 Vol.48 No.5

Gas grafting induces esterification between fatty acid chloride and polar group of cellulose, such as hydroxyl groups. Main factors of gas grafting reaction include reaction conditions such as reaction time, concentration, and temperature as well as characteristics of raw material. In this study, different kinds of pulp were used as raw materials of gas grafting in order to investigate the influence of pulp types and fiber length on the reaction efficiency. Pulp fibers grafted did not absorb water regardless of pulp types and fiber length distribution. Reacted fatty acid chloride contents of Sw-BKP was lower than those of BCTMP and DIP. However, Sw-BKP showed the best efficiency of gas grafting due to the lowest formation of residual fatty acid chloride. According to the decrease in fiber length, total amount of fatty acid chloride involved in gas grafting was increased. Un-reacted fatty acid chloride resulted in increase in free fatty acid residue. In case of fractionated BCTMP, un-reacted fatty acid chloride and total used fatty acid chloride during gas grafting reaction of BCTMP, which had passed 100 mesh screen, dramatically increased. Furthermore, it was assumed that short fiber length and high amount of fines had adverse effects on the efficiency of gas grafting.

재생 섬유에 대한 염화지방산의 기상 그래프트 반응

이태주(Tai Ju Lee),서진호(Jin Ho Seo),이명구(Myung Ku Lee),류정용(Jeong Yong Ryu) 한국펄프·종이공학회 2016 펄프.종이기술 Vol.48 No.4

Paper is extremely versatile because it is light, inexpensive, biodegradable, and recyclable product. However, it is very sensitive to water. Hence many synthetic resins, that is polyethylene and polylactic acid are often used as barrier coating materials in order to block water absorption into paper. However, the resins are harmful to the environment because they cannot be biodegradable and repulpable. Gas grafting based on chromatogeny chemistry is an alternative to synthetic resins. Hydrophilic surface of fiber can be changed into hydrophobic characteristics by gas grafting. Mechanism of the grafting can be explained as hetergeneous esterification between carboxylic groups in fatty acid chloride and hydroxyl groups in cellulose. In this study, parameters for gas grafting of recovered papers including ONP (old newspaper), OMG (old magazine), and white ledger were investigated. Basically hydrophobicity of ONP was lower than that of OMG and white ledger after flotation. However hydrophobicity of ONP was improved by hyperwashing. From the results, ERIC value gives great influence on efficiency of gas grafting. The esterification could be hampered by residual ink. Calendering gave positive effect to efficiency of gas grafting. Cobb value decreased with increase in sheet density by calendering. Also, hydrophobicity of ONP was improved by acetone washing and repeat of gas grafting. Consequently, residual ink, calendering, and acetone washing followed by repeat of gas grafting were important influencing factors of gas grafting by fatty acid chloride.

종이의 기상 그라프트 소수화 처리가 재생지의 물성에 미치는 영향

노규환,신유림,강현지,김한별,류정용 한국펄프·종이공학회 2023 펄프.종이기술 Vol.55 No.2

In this study, Hw-BKP handsheets were prepared and treated with gas grafting to achieve hydrophobicity. The study examined the changes in paper strength and water resistance after repeating the recycling and gas grafting process. However, the gas grafting treatment caused a decrease in the strength of the handsheet, presumably due to deterioration of the handsheet by hydrochloric acid, by-product from grafting. Furthermore, the fatty acid reacted on the surface of the fiber acted as an interfering factor with the hydrogen bonding between the fibers, resulting in a reduction in the strength of the handsheet after recycling. Although the water resistance of the handsheet decreased after its first recycling following gas grafting, the study confirmed that repeating the grafting process twice enhanced the handsheet's water resistance even after recycling. Therefore, recycling the grafted paper and repeating the grafting treatment once more is an effective method of hydrophobization t o m inimize the cellulose f ibers' wetting in water. Although the beating treatment restored the recycled handsheet's absorbency, it did not significantly recover the strength or formation of the recycled paper. .

An enhanced adsorption efficiency of the amine-grafted mesoporous silica for acid gas removal from natural gas.

이동훈,임동하 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.1

The removal of acid gases such as CO₂and H₂S from natural gas is an important process. Amine process is widely applied to remove acid gas, but, it has some problems such as energy consumption, corrosion. To overcome these problems, physical adsorption with solid adsorbents is an alternative. Mesoporous materials have been generally used to capture acid gases, but they are limited because of the low selectivity and strong water inhibition. Thus, one of solution is to high adsorption capacity with small amount of amine-grafted adsorbents. In this study, to develop selective adsorbents for acid gas removal, the amine-grafted mesoporous silica was prepared by direct synthesis, impregnation. And the adsorption performance was conducted using a fixed bed reactor to examine acid gas adsorption capacity. The amine-grafted adsorbents showed the increased breakthrough and saturation time, and thus the adsorption capacity is expected to increase resulting in decreasing of adsorption reactor size.

반복된 기상 그라프트 처리로 소수화한 HwBKP 섬유의 PP 내 분산특성 연구

신유림,노규환,유하운,김형운,이진솔,류정용 한국펄프·종이공학회 2023 펄프.종이기술 Vol.55 No.2

This study investigated the fiber dispersion characteristics and physical property changes of HwBKP-PP composites through repeated hydrophobization and recycling of cellulose fiber. The gas-grafted paper was disintegrated and then gas-grafted again to achieve uniform dispersion of the cellulose fibers with PP. With each gas grafting repetition, the interfacial affinity between the hydrophobized fibers and PP improved, leading to enhanced tensile strength and melt flow index of the HwBKP-PP composite material due to the improved fiber dispersibility. However, recycling of hydrophobic paper resulted in the loss of fines in the recycled paper, so that increase in average fiber length caused fiber agglomeration, resulting in poor dispersibility, and subsequently decreasing the tensile strength and melt flow index of the composite. .

Room-temperature, one-pot process for CO₂ capture membranes based on PEMA-g-PPG graft copolymer

Jung, Jung Pyo,Park, Cheol Hun,Lee, Jae Hun,Bae, Youn-Sang,Kim, Jong Hak Elsevier 2017 Chemical engineering journal Vol.313 No.-

<P><B>Abstract</B></P> <P>Gas separation based on membrane technology can possibly be used to offset the greenhouse effect because of its high energy efficiency and low cost. To achieve commercialization, it is essential that the gas-separation membrane demonstrates high performance and scalability. Here, we first report the room-temperature, one-pot process for CO<SUB>2</SUB> capture membranes based on the synthesis of a graft copolymer comprising of poly(ethylene-alt-maleic anhydride) (PEMA) main chains and poly(propylene glycol) (PPG) side chains. As confirmed by Fourier transform infrared (FT-IR) and nuclear magnetic resonance (<SUP>1</SUP>H NMR) spectroscopy, the PEMA-g-PPG synthesis was based on the complete reaction (100% conversion) of O-(2-aminopropyl)-O′-(2-methoxyethyl) polypropylene glycol (AMPPG) with PEMA in butanol (BuOH) at room temperature. X-ray diffraction (XRD) and differential scanning calorimetry (DSC) revealed that the PEMA-g-PPG graft copolymer exists in an amorphous rubbery state with a bimodal microstructure. Without any post-treatment, the as-synthesized PEMA-g-PPG in BuOH was directly coated onto a microporous polysulfone support to form thin-film composite membranes. The membrane exhibited high selectivity (i.e. 82.6 for CO<SUB>2</SUB>/N<SUB>2</SUB> and 26.8 for CO<SUB>2</SUB>/CH<SUB>4</SUB>) and good CO<SUB>2</SUB> permeability (99.1Barrer), outperforming conventional PEBAX block copolymer membranes. CO<SUB>2</SUB> uptake measurements confirmed enhanced CO<SUB>2</SUB> permeation resulting from the improved solubility of CO<SUB>2</SUB> in PEMA-g-PPG compared with those of neat PEMA and PEBAX. The PEMA-g-PPG membrane could be commercially feasible owing to its simple coating process, low cost, high selectivity, and scalability.</P> <P><B>Highlights</B></P> <P> <UL> <LI> PEMA-g-PPG graft copolymer was synthesized in BuOH at room temperature. </LI> <LI> One-pot, 100% conversion reaction between PEMA and AMPPG occurred. </LI> <LI> PEMA-g-PPG exhibited an amorphous, rubbery, bimodal structure. </LI> <LI> Separation properties were superior to those of PEMA, PDMS, and PEBAX. </LI> <LI> Overall process is inexpensive and accessible, with excellent scalability. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

2LB-1 염화지방산의 Gas Grafting에 의한 방수, 방습지 개발

류정용,이명구,이광섭 한국공업화학회 2017 한국공업화학회 연구논문 초록집 Vol.2017 No.1

셀룰로오스를 활용한 세계 최대의 화학산업은 제지산업이었으나 정보통신 기술의 발전과 생활양식의 변화에 따라 선진국의 경우 종이의 사용량이 더 이상 늘지 않고 있으며 특히 신문용지의 경우 생산량이 오히려 급속히 줄고 있어 새로운 용도의 제품생산을 목적으로 한 지종의 전환이 시급히 요청되고 있다. 대체 지종으로 추천되는 산업용 포장지 중 폴리에틸렌 라미네이팅 처리 등으로 구성되는 기존의 방수지, 방습 포장지를 친환경 재생 종이로 대체하는 친환경 기능성 포장소재의 표면 개질 기술로서 염화지방산을 활용한 펄프 sheet의 표면 에너지 저하법이 대두되고 있다. 본 연구에서는 이를 위하여 상기 방수, 방습 포장지용 친환경 재생가능 종이를 개발하고 기존의 방수, 방습 포장지를 대체하는 등 친환경 기능성 포장소재의 개발을 시도하였다. 재생지에 대한 Chromatogenic treatment의 pilot trial 및 분석 평가를 실시하고 방수, 방습포장 등으로 활용되는 소수성 포장지의 시험생산 및 양산을 기술 감수를 실시하였다. 염화지방산의 반응 효율 분석 및 부가반응 제어기술 개발과 함께 표면 개질처리로 압착가열 건조를 실시하였다.

Facilitated Transport Membranes Based on PVA-g-PAA Graft Copolymer

박민수,강미소,박보령,김정훈,김종학,Park, Min Su,Kang, Miso,Park, Bo Ryoung,Kim, Jeong-Hoon,Kim, Jong Hak The Membrane Society of Korea 2021 멤브레인 Vol.31 No.3

It is inevitable to generate incomplete combustion gases when mankind utilizes fossil fuels. From this point of view, gas separation process of combustion gas suggests the possibility of recycling CO gas. In this study, we fabricated a facilitated transport polymeric composite membrane for CO separation using AgBF₄ and HBF₄. The copolymer was synthesized via free-radical polymerization of poly(vinyl alcohol) (PVA) as a main chain and acrylic acid (AA) monomer as a side chain. The polymer synthesis was confirmed by FT-IR and the interactions of graft copolymer with AgBF₄, and HBF₄ were characterized by TEM. PVA-g-PAA graft copolymer membranes showed good channels for facilitated CO transport. In this perspective, we suggest the novel approach in CO separation membrane area via combination of grafting and facilitated transport. 화석 연료를 사용할 때, 불완전 연소는 필연적으로 발생하는 문제이다. 이러한 관점에서 연소 후 기체 분리는 불완전 연소 기체의 재활용 가능성을 시사한다. 이와 관련하여 본 연구에서는 일산화탄소 기체 분리용 촉진수송 고분자 분리막을 제조하였다. 이를 위해 poly(vinyl alcohol) (PVA) 주사슬 기반으로 acrylic acid (AA) 단량체를 자유 라디칼 중합법으로 PVA-g-PAA 공중합체를 제조하였다. 본 공중합체를 일산화탄소 활용에 적용하는 사례는 처음이며, 제조한 공중합체는 AgBF₄ 염과 HBF₄를 혼합하여 기체 분리막에 적용하였다. 공중합체 합성 결과는 FT-IR을 통해 분석하였으며, 공중합체와 AgBF₄, HBF₄의 상호작용은 TEM를 통해 분석하였다. 염의 첨가를 통해 일산화탄소 기체의 촉진수송 채널을 형성하였으며 이를 통해 일산화탄소 분리막 분야에 촉진수송 및 그래프팅 방법이라는 새로운 접근법을 제시하였다.

Grafting된 섬유를 이용한 셀룰로오스 비즈의 소수성 특성 분석

허도현(Do-Hyun Heo),조병욱(Byoung-Uk Cho) 한국펄프·종이공학회 2024 한국펄프·종이공학회 학술발표논문집 Vol.2024 No.4

염화팔미토일의 기상 그라프트 반응에 의한 PVA 코팅층의 소수화 효율 분석

이광섭(Kwang-Seob Lee),이재훈(Jae-Hun Lee),이명구(Myoung-Ku Lee),류정용(Jeong-Yong Ryu) 한국펄프·종이공학회 2018 펄프.종이技術 Vol.50 No.4

Gas grafting of cellulose with fatty acid chloride based on chromatogenic chemistry is an effective method which can provide paper with hydrophobic characteristic. In case of gas grafting with fatty acid chloride, various reaction parameters such as concentration of fatty acid chloride, reaction temperature, and reaction time are very important for the optimization of the gas grafting of cellulose. In this study the gas grafting efficiency of PVA (polyvinyl alcohol) coated paper at the various conditions was evaluated by measuring water resistance such as Cobb1,800 size and water contact angle. Also quantitative analysis was performed for determining reacted or un reacted fatty acid chloride by using ATR spectroscopy and GC. As a result, when the content of palmitoyl chloride esterified with a hydroxyl group at 1% concentration of palmitoyl chloride and 180℃ of react temperature was less than 1 g/㎡, Cobb1,800 size degree was less than 10 g/㎡. And it was found that Cobb1,800 size value, water contact angle, ratios of absorption peak of 1,735 cm<SUP>-1</SUP>/3,300 cm-1, amount of grafted fatty acid was improved with increase in concentration of palmitoyl chloride, temperature, and reaction time. And there was good correlation between GC analysis, ATR spectroscopy analysis and Cobb1,800 sizing degree for evaluation of the grafting efficiency. It should be noted that only water contact angle could not be used to evaluate the grafting efficiency.