표면처리된 실리카를 충전한 에폭시 수지계의 물성에 관한 연구 : Ⅰ . 실리카의 표면처리 및 혼합 물성

홍석표,최상구 ( Suk Pyo Hong,Sang Goo Choi ) 한국공업화학회 1990 공업화학 Vol.1 No.1

결정성 실리카의 표면을 아민(TEA, CTMAB, BETAC) 및 과산화물(BPO) 촉매를 사용하여 실란(A 187), 액상고무(CTBNx8), 비닐단량체(AA, MMA, 2-HEA, GMA) 등으로 차례로 반응시켜 새로운 표면처리 실리카를 제조하였다. 표면처리 효과를 검토하기 위하여 실리카를 에폭시 수지에 전체 혼합물 중 0∼36%(부피 %)의 범위로 혼합하여 혼합점도 및 침전율의 변화를 시험하였다. 실험결과 표면 피복량은 반응 촉매의 양과 종류에 의존하였으며, 촉매량 0.1∼20%에서 실리카에 대한 피복량은 2.5∼5.8% 범위의 값을 표시하였고, 실리카의 표면이 실란/고무, 실란/고무/비닐로 점차 처리됨에 따라서 무처리물이나 실란처리물에 비하여 점도가 저하되었으며, 침전율도 낮은 값을 표시하였다. 표면처리 상태는 처리제의 종류에 따라서 각기 다른 특성을 나타내었다. Surface of crystalline silica was sequentially reacted with silane(A 187), liquid rubber(CTBNx8) and vinyl monomer(AA, MMA, 2-HEA, GMA) in existance of amines(TEA, CTMAB, BETAC) or peroxide(BPO). By mixing it with epoxy resin at a ratio 0∼36%(volume %) of total component, liquid properties of mixtures was investigated experimentally. i) Coating ratio depended on quantity and sorts of catalyst. ii) Total coating of 2.5∼5.8% was attained by using 0.1∼2.0% of catalyst. iii) Treated surfaces represented each different features in according to sorts of treatment. iv) Silane/rubber or silane/rubber/vinyl represented lower viscosity and settling than non-treated or silane-treated.

비닐에스테르 수지의 합성촉매에 관한 연구

홍석표,최상구 ( Suk Pyo Hong,Sang goo Choi ) 한국공업화학회 1991 공업화학 Vol.2 No.3

합성촉매로 triethrlamine(TEA), triethylbenzyl ammonium chloride(TEBAC), cetyltrimethyl ammonium bromide(CTMAB) 등의 아민 및 chromium acetyl acetate(CAA), triphenylantimony(TPA) 등의 유기금속화합물을 사용하여 합성촉매가 비닐에스테르수지의 합성 및 물성에 미치는 영향을 연구하였다. 반응성, 경화시간, 저장안정성 등을 고려해 볼 때, 촉매의 적절한 사용량은 methacrylic acid(MAA)에 대하여 아민계의 경우에는 1.7∼2.2%(중량 %) , 유기금속계의 경우에는 2.5-3.1%(중량 %)였다. 촉매의 반응성은 TEA > TEBAC > CTMAB > CAA > TPA의 순이었으며, 촉매의 온도의존성은 110 ℃ 이상에서 크게 나타났다. 수지의 저장안정성은 합성 후 TPA를 MAA에 대하여 2.0% (중략 %) 이내의 범위에서 첨가하였을 때, 경화시간의 지연됨이 없이 개량되었다. Vinylester was syntheszed in the presence of amine and metal catalysts, such as triethylamine (TEA), triethylbenzyl ammonium chloride (TEBAC), cetyltrimethyl ammonium bromide (CTMAB), chromium acetyl acetate (CAA), and triphenylantimony (TPA). Apropriate use of amine and organometal catalysts were 1.7∼2.2% (Wt. %), 2.5∼3.1% (Wt. %) of charged methacrylic acid (MAA) in respect of reactivity, gel-time, and storage stability. The Order of reactivity was TEA > TEBAC > CTMAB > CAA >TPA. Temperature independence of catalyst showed more large deviation above 110 ℃. Storage stability could be improved without delay of gel-time by adding TPA in 2.0% (Wt. %) of charged MAA after synthesis.

비닐에스테르 수지의 구조 및 분자량이 물성에 미치는 영향

홍석표,최상구,유길상 ( Suk Pyo Hong,Sang Goo Choi,Kil Sang You ) 한국공업화학회 1992 공업화학 Vol.3 No.2

분자량 350∼360을 가진 비스페놀형 에폭시 수지(DER 331)를 전체 에폭시 성분 중 50% 이내의 범위에서 분자량 1,000∼1,600을 가진 비스페놀형 에폭시수지(DER 662, 664) 및 분자량 800∼1,000을 가진 노블락형 에폭시수지(DEN 439)와 혼합 사용하여 합성한 비닐에스테르수지의 액상 및 경화물성을 연구하였다. 희석점도는 분자량과 용해성의 영향을 받았으며 저분자량의 할량이 늘어날수록 낮아졌다. 경화시간은 MAA의 양에 영향을 받았으며 저분자량의 함량이 늘어날수록 비스페놀형은 빨라졌고 노블락형은 변화를 보이지 않았다. 경도와 신율은 분자구조의 영향을 받았으며 저분자량의 함량이 늘어날수록 떨어졌다. 굴곡강도와 인장강도는 DER 331 함량 30∼40%에서 가장 우수했다. Vinylester resin was synthesized by reacting epoxy resin with MAA(methacrylic acid) at a equivalent ratio of 1.1/1.0 in the presence of N, N dimethyl benzylamine. Low molecular weight epoxy(DER 331) was used together with higher molecular weight epoxy(DER 662, DER 664) and a novolac epoxy(DEN 439), and the amount of DER 331 was not over 50% of the total epoxy components. Viscosity, cure time and mechanical properties of the vinylester resin were profoundly influenced by the quantity of reacted MAA, and the structure and molecular weight of the epoxy resin. Tensile and flexural strength appeared to be the greatest when DER 331 fraction was 30∼40%.

표면처리실리카를 충전한 에폭시수지계의 물성에 관한 연구 : Ⅱ . 에폭시 수지 경화물의 물성

홍석표,최상구 ( Suk Pyo Hong,Sang Goo Choi ) 한국공업화학회 1990 공업화학 Vol.1 No.2

γ- Glycidoxy propyl trimethoxy slilane, CTBN rubber(carboxyl terminated butadiene acrylonitrile rubber), GMA(glycidyl methacrylate) 등을 TEA(triethylamine) 및 BPO(benzoyl peroxide) 존재하에 결정성 실리카의 표면에 단계적으로 반응시켜 2.5∼5.8%(중량%)의 피복율을 가진 표면처리 실리카를 제조하였다. 이것을 전체 혼합물 중 0∼60%(중량%)가 되도록 에폭시 수지 및 MTHPA (methyltetrahydrophthalic anhydride) 와 혼합한 후 경화시켜 굴곡특성 및 열적특성을 시험하였다. 시험결과, 충전재 함량 35∼55%(중량%)에서, 실란/고무 또는 실란/고무/비닐로 처리된 실리카를 충전한 것은 에폭시 수지에 고무를 직접 3% 혼합하고 여기에 표면 처리하지 않은 실리카를 충전한 것에 비하여 굴곡강도와 Tg는 각각 평균 25%, 13%높은 값을, 굴곡탄성율은 5% 낮은 값을 나타내었다. γ- Glycidoxy propyl trimethoxy slilane, CTBN rubber(carboxyl terminated butadiene acrylonitrile rubber) and GMA (glycidyl methacrylate) were reacted with the surface of silica one by one in existence of TEA(triethylamine) or BPO(benzoyl peroxide). The amount of reactant was 2.5-5.8% of treated silica weight. The treated silica was mixed with epoxy resin and MTHPA(methyltetrahydrophthalic anhydride) in the range of 0∼60% (wt. %) of total component. The flexural and thermal properties were tested for cured products. In filler content 35∼55%, the using of silica treated with silane/rubber or silane/rubber/vinyl represented 25% higher flexural strength, 5% lower flexural modulus and 13% higher than mixing liquid rubber 3% with epoxy resin containing untreated silica.

보강섬유의 배향이 고분자 복합재료의 물성에 미치는 효과

崔相久,李和雨,洪錫杓 全北大學校 1993 論文集 Vol.35 No.-

The tensile and flexural strength of unsaturated polyester laminated with 20% glass-fiber(volume %) were tested. Those were compared with its abtained from Holister's equation. The strengths of laminated polyester were mainly depended on the properties of interface between fiber and resin than the strengths of material itself. For crossplied laminates, correct strength coincided with Holister's were not abtained, but could be explained by Holister's theory. The fractural strength of orientation angle 0∼5˚ was influenced by shear resistance besides the strength of glass fiber.

CTBN고무 분산 에폭시 복합재의 기계적물성 및 파단면에 관한 연구

洪錫杓,崔相久 全北大學校 1989 論文集 Vol.31 No.-

We examined the mechanical properties (flexural and impact) and fracture surface of CTBN(carboxyl terminated butadiene acrylonitrile) rubber dispersed epoxy composites which are cured with MTHPA(methyl tetrahydro phthalic anhydride) or DICY(dicyandiamide). Rubber dispersed epoxy composites are prepared to blend epoxy mixture with CTBN rubber or CTBN rubber modified epoxy. It contains 0-25% CTBN rubber of liquid compoment. The results obtained in this experiment are as follows ; 1. The flexural stength is better in using the CTBN rubber than CTBN rubber modified epoxy. 2. In excess of 25% CTBN rubber, the cured epoxy composites are closed to rubber rather than epoxy in properties. It is very flexible. 3. In respect of the flexural stength and flexural modulus, CTBN x13 rubber is superior to CTBN x8 rubber. In excess of 5% CTBN rubber, The mechanical properties of both decrease sharply. 4. In respect of the impact stength, flexural stength and rubber dispersion, MTHPA is superior to DICY.

벽시계틀 소재로 사용되는 목재와 플라스틱의 접착력 향상에 관한 연구

洪錫杓,崔相久,金鍾石 全北大學校 1991 論文集 Vol.33 No.-

Wood and plastic were used as elemental materials of the frame of clock. In this research, it was studied to improve adhesive strength between this materials by new adhesion process. Vinyl or acryl emulsion(H-403, H-422, Y-840, Y-850) was used as the adhesive. The adhesive properties was tested experimantally on various partial process including sanding, cleaning of sanded surface and pressing of bonded areas. The results obtained in this experiments were follows : 1) Y-850 represented most excellent adhesive properties. 2) The maximum of adhesive strength could be obtained by sanding with sand paper #600, pressing of 0.3∼0.5kg/㎠, and cleaning with acetone. In that case, increase of 20% in adhesive strength was showed than obtained by traditional process.

에폭시 수지를 혼합한 아스팔트 방식재의 특성

홍석표,최상구,강석근,이화우 全北大學校 1995 論文集 Vol.39 No.-

Epoxy resins were mixed with asphalt solution in the range of 0 - 60phr for the total components. The blending properties, curing properties, and surface properties for mixtures were investigated experimentally. Compatability of epoxy resins with asphalt were relatively good over mixture temperature 50℃. Interpenetrated polymer networks(IPNs) were partially formed between epoxy resins and asphalt. Increase of hardness was depended on the crosslinking density of epoxy resins and oxidation of asphalt. Defects of coated surface including crater, pinhole, and crack could be improved by adding epoxy resins 20 phr.

카본블랙의 종류 및 배합제의 혼합방법에 따른 NR/HNBR 블렌드의 특성

洪錫勻,庾吉祥,金鍾石,崔相久 全北大學校 1992 論文集 Vol.34 No.-

It was studied how physical properties, heat resistance, oil resistance, ozone resistance of NR(natural rubber)/HNBR(hydrogenated acrylonitrile butadiene rubber) blends influenced by different mixing methods and various carbon black types. Of the various mixing methods, masterbatch mixing method was better than others in considering the overall stabilities of the compounds. The most important parameter which influenced on heat, oil and ozone resistance was rubber material than sorts of carbon black. The resistance for heat, oil and ozone of NR compounds were improved by blending HNBR and these effects were revealed clearly at elevated temperatures.

자외선 경화형 불포화 폴리에스테르 수지의 합성과정이 저장안정성에 미치는 영향

洪錫杓,崔相久 全北大學校 1992 論文集 Vol.34 No.-

Storage stability of UV curable unsaturated polyester was studied in accordance with synthesis process and inhilitor charging. When resin was synthesized at 160∼170℃, storage stability was mainly influencd by reaction time. THQ showed best storage stability among inhibitors. Appropriate charge of THQ was 150ppm in initial of first reaction, 350ppm in initial of second reaction and 350ppm in SM thinning.