• Fibers and Polymers
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• 제2권2호
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• pp.108-115
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• 2001

Vinyl acetate was polymerized in ultraviolet-ray initiated bulk system at low temperatures using 2,2-azobis(2,4-dimethylvaleronitrile) (ADMVN) or 2,2-azobis(isobutyronitrile) (AIBN) as the photoinitiator, respectively. High molecular weight (HMW) poly(vinyl alcohol) (PVA) having number-average degree of polymerization ($P_n$) of 3,900-7,800 and syndiotactic diad (S-diad) content of 52.5-54.0% could be prepared by complete saponification of synthesized linear poly(vinyl acetate) (PVAc) having $P_n$ 5,900-9,400 obtained at conversion of below 30%. $P_n$ of PVA using ADMVN was larger than that of PVA using AIBN. On the other hand, conversion of the former was smaller than that of the latter, and it was found that the initiation rate of the ADMVN was lower than that of AIBN. This could be explained by a fact that the rate of photolysis of AIBN is faster than that of ADMVN due to the higher quantum yield or dissociation rate constant of AIBN than that of ADMVN. The $P_n$, syndiotacticity, and whiteness of PVA from PVAc polymerized at lower temperatures were superior to those of PVA from PVAc polymerized at higher temperatures.

• 대한화학회지
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• 제24권3호
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• pp.259-265
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• 1980

자유라디칼 telomerization 반응을 이용하여 스티렌-메타크릴산메틸 block 혼성중합체 (PS-b-PMMA)를 합성하였다. AIBN을 개시제로 사용하여 CCI$_4$로 스티렌을 telomerization시킨 다음 생성된 중합체의 $CCI_3$ 말단기를 macrotelogen으로 사용하여 AIBN 개시에 의해 메타크릴산 메틸을 다시 telomerization하여 스티렌-메타크릴산메틸 block 혼성중합체를 얻었다. Macrotelogen의 농도, 단위체의 농도, macrotelogen의 분자량, 반응온도 및 용매의 농도가 block 혼성중합체생성에 미치는 영향을 조사하였다. 반응조건을 조절하여, PMMA가 약 10무게%까지 포함된 block 혼성중합체를 얻었다.

• Bulletin of the Korean Chemical Society
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• 제6권5호
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• pp.284-287
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• 1985

Cyanoisopropyl radical derived from azobisisobutyronitrile (AIBN) by either thermolysis or photolysis reacts with oxygen to give cyanoisopropylperoxy radical which then was converted to acetone and cyano radical and/or acetyl cyanide and methyl radical. Of these products, acetone formed was quantitatively determined by the addition of thianthrene cation radical perchlorate to the reaction mixture. The results showed that 55.7 mmol, 16.9 mmol, and 16.0 mmol of acetone were formed for 7 hours from 1 mol of AIBN at $82{\pm}1^{\circ}C$ in acetonitrile, carbon tetrachloride, and benzene, respectively. However, 22.2 mmol of acetone was formed from photolysis of 1 mmol of AIBN in acetonitrile. The value decreased to 13.2 mmol by bubbling argon into the solvent prior to photolysis.

• Macromolecular Research
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• 제14권4호
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• pp.466-472
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• 2006

The kinetic behavior of emulsion polymerizations of styrene in the presence of sulfonated N-hydroxy ethyl aniline (SHEA) was investigated with two initiators: 2,2'-azobisisobutyronitrile (AIBN) and potassium persulfate (KPS). SHEA was synthesized using a stepwise polyurethane reaction method from 3-hydroxy-1-propane sulfonic acid sodium salt, isophorone diisocyanate (IPDI), and N-(2-hydroxyethyl) aniline. Stable core-shell poly(styrene/sulfonated N-hydroxy ethyl aniline, St/SHEA) latex particles were successfully prepared by using an appropriate amount of AIBN, in which SHEA plays the role of 'surfmer', i.e., acting as both a surfactant in the emulsion polymerization and a monomer in the chemical oxidative polymerization. The kinetic behavior was dissimilar to that of typical emulsion polymerization systems. A long inhibition period and low rate of polymerization were observed due to radical loss by the oxidative polymerization of SHEA. It was concluded, due to the low water-solubility of AIBN and retardation reaction by SHEA, that the initial loci of polymerization were monomer droplets. However, growing polymer particles as polymerization loci became predominant as polymerization proceeded. It was suggested that AIBN was more effective than KPS in the preparation of the core-shell type poly(St/SHEA) latex particles. With KPS, no substantial polymerization was observed in any of the samples.

• 폴리머
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• 제24권3호
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• pp.287-298
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• 2000

DVB (divinylbenzene)를 가교제로 하여 마이크로미터 크기의 단분산상 폴리스티렌 입자를 분산 중합법으로 제조하면서, 반응 온도와 단량체, 개시제, 용매 및 공용매의 농도, 안정제 poly(N-divinylpyrrolidone) (PVP) 함량과 분자량, 그리고 DVB의 함량이 전환율과 생성 입자의 크기 및 분포도에 미치는 영향을 조사하였다. 분산매로는 에탄올을, 개시제로 AIBN, 공통 분산매로톨루엔, 그리고 안정제로는 분자량 40000의 PVP를 사용하였다. 반응온도가 높아지고 개시제의 농도가 1%에서 4%로 증가할수록 반응속도와 전환율은 상승하고 모든 반응조건에서 10시간의 반응 결과 전환율과 입자의 크기는 거의 완결 단계에 이르렀으며, 오히려 24시간 동안 반응된 입자의 안정성은 10시간의 것보다 뒤떨어졌다. 또한 반응온도의 상승이 개시제의 농도변화보다 반응속도와 전환율에 더 민감한 영향을 미치는 것으로 관찰되었다. 각각 반응물의 조성을 변화시키면서 입자크기 및 분산도의 변화를 조사한 결과, 표면 특성이 안정하며 단분산상의 분포도를 갖는 구형의 고분자 입자를 중합할 수 있는 최적의 조건은 0.5% DVB, 25% 스티렌 단량체, 20-25% 톨루엔, PVP 농도는 10~15%, AIBN의 농도는 2와 4%이었으며, 이 조건에서 10시간의 반응으로 합성된 비드의 평균 입자경은 각각 3.9~4 $\mu\textrm{m}$와 3.4~9.3 $\mu\textrm{m}$이었다.

• Elastomers and Composites
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• 제58권3호
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• pp.128-135
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• 2023

To improve the adhesive strength of natural rubber (NR) for a seismic isolation damper, citraconic acid-g-NR (CCA-g-NR) was synthesized via the melt grafting of citraconic acid (CCA) onto NR using an azobisisnomerobutyronitrile (AIBN) initiator. Subsequently, the influence of CCA and AIBN concentrations on the graft ratio G/R (%) and graft efficiency G/E (%) of the CCA-g-NR was investigated. The optimum CCA and AIBN concentrations required to achieve the desired G/R (3.49%) and G/E (49.8%) were found to be 7 phr and 0.13 phr, respectively. Additionally, we studied the influence of CCA-g-NR concentration on the mechanical properties (tensile strength, elongation at break, and modulus at 300%), adhesive strength, and cure characteristics of the rubber compound in the seismic isolation damper. As the concentration of CCA-g-NR increased, the elongation at break and adhesive strength of the compound increased, whereas its tensile strength and modulus at 300% decreased. Moreover, as the concentration increased, the maximum torque decreased and the scorch time was delayed to obtain an optimal vulcanization time.

• 대한화학회지
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• 제43권1호
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• pp.74-84
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• 1999

벤조트리아졸을 보조체로 사용하는 유기합성법은 거의 대부분 이온성 반응 메카니즘으로 설명되며 라디칼 반응을 이용한 벤조트리아졸의 응용은 거의 없었다. 벤조트리아졸의 N-1의 ${\alpha}$위치 탄소 원자에 라디칼 중심을 만든 후 벤조트리아졸의 다섯고리를 형성하는 질소 원자중에서 질소 분자가 빠져나감으로서 생성되는 페닐 라디칼의 반응을 연구하기위해 1[(aryl)(phenylseleno)methyl]benzotriazole, AIBN, 그리고 $Bu_3$SnH을 벤젠에 용해시키고 환류시켜 주었다. 이 반응 혼합물로 부터 2-aminodiphenyl selenide (16∼29%), 2-aminobiphenyl (9∼15%), diphenyl diselenide (30∼93%), 1-(arylmethyl)benzotriazole (9∼39%), 그리고 tributyltinphenyl selenide (10∼36%)을 얻었으며, AIBN없이 과량의 $Bu_3$SnH 존재하에 같은 조건하에서 반응시키는 경우,diphenyl diselenide (53∼100%), benzotriazole (27∼35%) 그리고 1-(arylmethyl)-benzotriazole (16∼33%)와 함께 arylmethylidenaniline이 과량의 $Bu_3S_nH$에 의해 환원된 N-(arylmethyl)anilines (44∼66%)이 생성되었다. 같은 조건 하에서 6-aryl-6-(benzotriazol-1-yl)-1-hexenyl phenyl selenides, AIBN, 그리고 $Bu_3$SnH의 반응으로부터 6-aryl-6-phenylamino-1-hexene(9∼31%)과 1-aryl-1-oxo-5-pentene (15∼44%)을 얻었다. 이들 생성물의 생성 메카니즘을 제시하였으며 벤조트리아졸이 합성 보조체로 이용된 경우 $Bu_3$SnH에 의해 벤조트리아졸의 세개의 질소 원자를 포함하는 다섯원자고리로 부터 라디칼 반응에 의해 질소 분자가 빠져나가는 것을 보여준 새로운 예이다.

• 폴리머
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• 제25권5호
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• pp.754-758
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• 2001

Vesicle을 단량체가 중합 반응을 할 수 있는 장소로 사용하기 위하여, vesicle 내의 소수성부분에 단량체와 가교제를 집어넣었다. 즉 dimethyldioctadecylammonium bromide를 증류수 속에서 초음파 분산을 하여 vesicle을 만든 후, 여기에 styrene과 divinylbenzene을 첨가한 다음 AIBN으로 중합시켰다. 형성된 고분자는 남겨두고 vesicle을 형성하였던 계면활성제들을 모두 에탄올로 추출해서 제거하여 순수 고분자로 이루어진 구형의 구조물을 얻었다. 그리고 methyl methacrylate와 ethylene glycol dimethacrylate를 이용해서도 고분자로 이루어진 구형의 구조물을 합성하였다.

• 산업기술연구
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• 제23권A호
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• pp.187-191
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• 2003

A hollow-fiber type polysulfone UF membrane was surface-coated with hydroxyethylmethacrylate (HEMA). The effect of various coating parameters on permeation flux, such as concentration ratio of AIBN/HEMA, solvent(water or methanol), and UV irradiation time, was investigated. The water permeation flux of oil-emulsion increased with concentration ratio of AIBN/HEMA, and increased with UV irradiation time. The flux of the membrane coated in solution using methanol as a solvent was greater than that of the membrane coated in solution using water as a solvent. The flux of both the coated and the uncoated membrane declined with the operation. The flux decline means that the membrane fouling by oil-emulsion occurs. However, the fouling of the coated membrane was much less than that of the uncoated membrane.

• 대한화학회지
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• 제53권3호
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• pp.335-339
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• 2009

2-Hydroxyethyl methacrylate를 PDMS (polydimethylsiloxane)와 반응시켜methacrylate 말단기를 가진 PDMS prepolymer를 합성하였으며, 탄성 및 유연성을 증가시키기 위하여 AIBN 개시제를 사용하여 BMA(butyl methacrylate)와 공중합시켰다. 얻어진 공중합체의 함수율은 23%로 나타났으며, 가시광선 투과율은 83%, 산소투과율은 50 Dk/t 이상이었다. 이 중합체는 우수한 콘택트렌즈 재료로서의 특성을 보였다.