제 2 발표장 : DGEBA / DDS 에폭시수지계의 개별적 반응기구 및 물성

민병각(Byung Gak Min) 한국복합재료학회 1999 한국복합재료학회 학술발표대회 논문집 Vol.- No.2

탄소섬유의 사이징처리가 탄소섬유/나일론6 복합재료의 기계적 계면 특성에 미치는 영향

최웅기 ( Woong Ki Choi ),김병주 ( Byung Joo Kim ),민병각 ( Byung Gak Min ),배경민 ( Kyong Min Bae ),박수진 ( Soo Jin Park ) 한국고무학회 2010 엘라스토머 및 콤포지트 Vol.45 No.1

탄소섬유/나일론 수지 복합재료의 계면결합력의 향상을 위해 폴리아크릴로니트릴(PAN)계 탄소섬유의 표면에 실란계, 설파이드계, 이미드계 계면결합제를 이용해서 사이징 처리를 수행하였으며, 사이징 처리된 탄소섬유의 젖음성과 표면자유에너지는 접촉각을 통해 확인하였다. 사이징 처리되어 제조된 복합재료의 기계적 계면물성은 임계응력세기인자를 통하여 확인하였으며, 파단실험 후 파단면은 주사전자현미경을 통해 관찰하였다. 실험결과 실란계로 사이징처리된 탄소섬유가 다른 사이징 처리에 비해 표면자유에너지가 큰 것을 접촉각 측정을 통해 관찰하였다. 한편 사이징처리된 탄소섬유 강화 나일론 복합재의 경우 미처리 탄소섬유를 이용한 복합재에 비해 높은 기계적 계면강도를 보였다. 이러한 결과는 섬유의 표면자유에너지가 탄소섬유와 나일론6 기지 사이의 계면결합력의 증대를 유도하여 복합재료의 기계적 계면강도가 증가된 것으로 판단된다. The sizing treatments of PAN-based carbon fiber surfaces were carried out in order to improve the interfacial adhesion in the carbon fibers/nylon6 composite system. The parameter to characterize the wetting performance and surface free energy of the sized fibers were determined by a contact angle method. The mechanical interfacial properties of the composites were investigated using critical stress intensity factor (KIC). The cross-section morphologies of sized CFs/nylon6 composites were observed by SEM. As the experimental results, it was observed that silane-based sizing treated carbon fibers showed higher surface free energies than other sizing treatments. In particular, the KIC of the sizing-treated carbon fibers reinforced composites showed higher values than those of untreated carbon fibers-reinforced composites. This result indicated that the increase in the surface free energy of the fibers leads to the improvement of the mechanical interfacial properties of carbon fibers/nylon6 composites.

KOH 활성화 효과에 의한 흑연나노섬유의 전기화학적 거동

박수진(Soo Jin Park),유혜민(Hye Min Yoo),민병각(Byung Gak Min),이규환(Kyu Hwan Lee),변준형(Joon Hyung Byun) 한국고분자학회 2012 폴리머 Vol.36 No.3

본 연구에서는 화학적으로 활성 흑연나노섬유를 제조하여 그에 따른 전기화학적 거동을 확인하였다. 활성화 제로 KOH를 사용하였으며, KOH와 흑연나노섬유의 비를 무게비로 각각 0, 1, 2, 4, 및 5로 처리하여 표면과 기공 특성을 연구하였고, 그에 따른 전기화학적 거동을 살펴보았다. 활성화된 흑연나노섬유의 결정구조와 표면특성은 각 각 X-선 회절분석법(XRD), 주사전자현미경(SEM) 분석방법을 이용하여 확인하였으며, 기공 특성은 비표면적 장치 (BET)를 이용하였으며 질소흡착 등온선에 의해 조사하였다. 전기화학적 특성은 10 mV/s의 주사속도로 순환전류전 압(cyclic voltammetry)을 통한 곡선으로 고찰하였으며 정전류법(galvanostatic method)으로 측정된 충방전 곡선을 통해 비축전용량을 계산하였다. 실험 결과로부터, 활성 흑연나노섬유의 전기화학적 거동은 KOH 양이 증가함에 따 라 향상되었으며, 4 배 처리된 활성 흑연나노섬유가 최대의 비축전용량을 가진 것으로 나타났다. 이것은 KOH 활성화 에 의해 활성 흑연나노섬유의 비표면적과 기공부피가 증가하기 때문인 것으로 사료된다. In this work, we prepared the activated graphite nanofibers (A-GNFs) via chemical activation with KOH/ GNFs ratios in a range of 0 to 5. The effect of KOH activation was studied in the surface and pore properties of the samples for electrochemical performance. The surface properties of A-GNFs were characterized by XRD and SEM measurements. The textural properties of the A-GNFs were investigated by N2/77 K adsorption isotherms using Brunauer-Emmett-Teller (BET) equation. Their electrochemical behaviors were investigated by cyclic voltammetry and galvanostatic charge-discharge performance. From the results, electrochemical performances of the A-GNFs were improved with increasing the ratio of KOH reagent. It was found that specific surface area and total pore volume of the A-GNFs were increased by KOH activation.

총설 : 엘라스토머 나노복합체(1)

방대석 ( Dae Suk Bang ),계형산 ( Hyoung San Kye ),조을룡 ( Ur Ryong Cho ),민병각 ( Byung Gak Min ),신경철 ( Kyung Chul Shin ) 한국고무학회 2009 엘라스토머 및 콤포지트 Vol.44 No.1

실란 커플링제에 따른 DGEBF 계열 에폭시의 열안정성 및 접착특성 평가

이동수(Dong Su Lee),이슬이(Seul Yi Lee),민병각(Byung Gak Min),서영수(Young Soo Seo),이봉화(Bong Han Lee),박수진(Soo Jin Park) 한국고분자학회 2014 폴리머 Vol.38 No.6

본 연구에서는 실란 커플링제의 함량에 따른 에폭시 복합재료의 열안정성 및 접착특성을 고찰하기 위하여,일반적으로 널리 사용되는 diglycidyl ether of bisphenol F(DGEBF)계 에폭시수지에 실란 커플링제로는 3-glycidoxypropyltrimethoxysilane(GPTMS)를 변량 배합하여 에폭시 시편을 제조하였다. TGA 데이터를 통해 고분자 분해온도(polymer decomposition temperature, PDT), 최대 중량 감소 시의 온도(temperature of miximum rate of weightloss, Tmax), 적분 열분해 진행 온도(integral procedural decomposition temperature, IPDT), 그리고 분해 활성화 에너지(Ea)를 구하였다. 또한 접착특성은 철판 사이에 제조한 에폭시 복합재료를 도포하여 접착력 시편을 제작하고, 상온에서 UTM(universal testing machine)을 사용하여 접착력을 측정하였다. 그 결과, DGEBF계 에폭시의 경우 실란커플링제 도입에 따라 미처리 에폭시 복합재료에 비해 접착력이 향상되었고, 일정 함량 도입 후에는 접착력이 오히려 감소하는 경향을 보였다. In this work, the epoxy specimens were prepared from diglycidyl ether of bisphenol F (DGEBF) with silanecoupling agents (3-glycidoxypropyl trimethoxysilane (GPTMS)) in different ratios. Thermal stability was studied in termsof polymer decomposition temperature (PDT), temperature of maximum rate of weight loss (Tmax), integral proceduraldecomposition temperature (IPDT), and decomposition activation energy (Ea) using TGA analysis. Adhesion propertiesof epoxy composite specimens were measured by UTM (universal testing machine) at atmosphere temperature. In thisresult, the adhesion properties of DGEBF were improved by addition of silane coupling agents compared to non-treatedepoxy resin. However, when the content of GPTMS agent is more than 10 phr, adhesion properties decreased withincreasing GPTMS agent.

2관능성 에폭시/생분해성 폴리부틸렌 숙시네이트 블렌드의 유변학적 특성 및 경화거동에 관한 연구

박수진 ( Soo Jin Park ),김승학 ( Seung Hak Kim ),이재락 ( Jae Rock Lee ),민병각 ( Byung Gak Min ) 한국복합재료학회 2002 Composites research Vol.15 No.6

본 실험에서는 2관능성 에폭시 수지(2EP)와 생분해성 poly(butylene succinate)(PBS) 블렌드의 유변학적 특성, 경화거동, 열안정성 그리고 기계적 특성을 살펴보았다. 유변학적 특성은 레오미터를 이용하여 등온 조건 하에서 검토하였고, 젤화 시간과 경화 온도를 이용한 Arrhenius 방정식을 적용하여 가교 활성화 에너지(E_c)를 구하였다. E_c는 2EP에 대한 PBS의 비율이 10 wt%로 증가함에 따라 증가하였다. DSC 측정 결과, 경화 활성화 에너지(E_a)는 E_c와 유사한 경향을 나타내었는데 이는 2EP와 PBS 사이의 분자상호작용이 증가하였기 때문으로 사료된다. 그리고 열안정성과 관련하여 분해 활성화 에너지(E_t)는 Horowitz-Metzger식을 이용한 적분법을 사용하여 구하였는데 PBS 10 wt%에서 증가하였다. 그리고 20 wt% PBS일 때 가장 높은 임계응력세기 인자를 보이는데, 이는 2EP/PBS 블렌드 시스템의 파괴인성이 증가하였기 때문으로 사료된다. In this work, the effect of biodegradable poly(butylene succinate)(PBS) in difunctional epoxy(2EP) resin was investigated in terms of rheological properties, cure kinetic, thermal stabilities, and mechanical interfacial properties. Rheological properties of the blend system were measured under isothermal condition using a rheometer. Cross-linking activation energies(E_c) were determined from the Arrhenius equation based on gel time and curing temperature. The Ec was increased in the presence of 10 wt% PBS as compared with neat 2EP. From the DSC results of the blends, the cure activation energies(E_a) showed a similar behavior with Ec due to the increased intermolecular interaction between 2EP and PBS. The decomposed activation energies(E_t) for thermal stability derived from the integral method of Horowitz-Metzger equation, were also increased in 10 wt% PBS. In addition, 20 wt% PBS showed the highest critical stress intensity factor(K-IC), which was explained by increasing the fracture toughness of the 2EP/PBS blend systems.

에폭시/PPO 블랜드물의 제조 및 특성 분석

閔丙珏 충주대 2001 한국교통대학교 논문집 Vol.36 No.2

The epoxy resin/poly(phenylene oxide)(PPO) blending systems as a use of matrix materials for printed circuit board(PCB) were specially prepared.A diglycidyl ether of bisphenol A(DGEBA) epoxy resin and an aromatic amine curing agent, 4,4'-diaminodiphenyl methane(DDM) were used in this study as the primary matrix materials, and PPO was blended additionally in order to improve the electric property of the system.Thermal and electric properties of the prepared epoxy resin/PPO blending systems have been investigated as a function of the concentration of PPO modifier.The glass transition temperature(Tg) was not changed noticeably up to the concentration of 10wt% of PPO and then decreased rapidly with further increment of the modifier.In addition the electric property was found showing the similar trend.The value of electric constant was decreased approximately 23% at 10wt% of PPO-modified epoxy system and then slightly increased again with further increment of PPO modifier over 10wt% concentration.

SBS 공중합체를 이용한 친환경 열가소성 탄성체

민병각 忠州大學校 2008 한국교통대학교 논문집 Vol.43 No.-

Polyvinylchloride(PVC) has been used as a polymeric material for replacing the natural leather in the various applications with its relatively competitive price and excellent processibility. However, the use of PVC is restricted more and more due to the environmental problem such as emission of dioxin associated with its combustion. Recently, the studies for the development of environmental compound replacing PVC are carried out widely. In this study a principal thermoplastic elastomer, Styrene-Butadiene-Styrene(SBS) copolymer is used as a base material and modified by the secondary thermoplastic polymers in order to obtain a new recycleable environmental compound which has the required properties for replacing PVC. Two SBS used in this study are solution polymerized block copolymers. They have styrene content of 30 and 40 wt% respectively. The thermoplastic polymers used as modifier are High Impact Polystyrene(HIPS) and Polypropylene(PP). In order to increase the processibility and flexibility white oil was added in the range of 20 to 75 phr. Three compounds with different formulations were prepared by using a 25mm twin screw extruder under the conditions of 200℃ extrusion temperature and 150rpm extrusion speed. The prepared compounds were used for the characterization of rheological and mechanical properties. We presented in this paper the comparative data of rheological property and mechanical properties such as hardness, tensile strength, strain to break, tear strength and bounce impact elasticity.

경화 조건이 에폭시수지계의 역학적 거동에 미치는 영향

閔丙珏 충주대 산업과학기술연구소 1998 産業科學論文集 Vol.6 No.-

The mechanical behaviors of a DGEBA based epoxy resin(Epikote 8283) cured with an aromatic amine curing agent DDS were studied as a function of cure temperature and cure cycle. The glass transition temperature(which depends on the extent of cure) and the large strain properties including fracture toughness and tensile strength, showed a linear increase with increasing final cure temperature regardless of cure cycle, and level off toward the cure temperature of 200℃. In contrast, the flexural modulus which is a small strain property was not influenced greatly by cure temperature and cure cycle. From the results obtained in this study we infer that the large strain properties of the resin may not be inversely proportional to the crosslink density, but rather that they are more dependent on other structural parameters such as the flexibility of the crosslinked network chains and the free volume entrapped in the network.

Alexander-Hauduroty의 非抗酸性三重 梁色에 依한 結核菌의 檢出에 對하여

閔炳珏 醫藥係社 1959 綜合 醫學 Vol.4 No.1