• 한국세라믹학회지
• /
• 제41권3호
• /
• pp.253-258
• /
• 2004

Polyacrylamide(PAA) 겔법은 매우 간단한 중합법이며, 고분자 망상구조가 $\alpha$-Al$_2$O$_3$ 분말의 응집을 억제하므로 미 응집된 나노 크기의 $\alpha$-Al$_2$O$_3$ 분말은 polyacrylamide(PAA) 겔법을 통하여 성공적으로 합성되었다 본 연구에서는 황산알루미늄, acrylamide 및 N,N'-methylene-bis-acrylamide(BIS)의 여러 농도에서 합성된 겔 전구체를 공기 중에서 110$0^{\circ}C$, 2시간동안 하소시켜서 약 8-l5 nm의 직경을 가진 나노 $\alpha$-Al$_2$O$_3$ 입자들을 제조할 수 있었다. Acrylamide에 대한 황산알루미늄의 몰비를 증가시켰을 때는 나노 입자들의 크기는 변하지 않았지만, acrylamide에 대한 BIS의 몰비를 증가시켰을 때는 나노입자들의 크기는 작아지는 경향을 나타내었다.

• Environmental Engineering Research
• /
• 제11권4호
• /
• pp.208-216
• /
• 2006

In order to create a single flocculant/dual flocculation system, polyacrylamide-co-trimethyl ammonium ethyl acrylate chloride (TAEAC) polymers with varying molecular weights and structures were prepared for use of flocculants. The higher the cationic density of the polymer is higher, the higher was the conversion rate and the ratio of monomer. An acrylamide as nonionic monomer was less reactive than a TAEAC as cationic monomer. The branched polymer which was polymerized with a cross-linking agent, N, N-methylene bis-acrylamide had a higher stability and higher viscosity than a linear polymer but its dewatering efficiency was poor in a single flocculation system. In the case of single flocculant/dual flocculation, the branched polymer has better flocculation efficiency and the water content of the dewatered cakes was lower than the others, as the result of a re-flocculation effect. The optimum conditions for dual flocculation are a sequence in which the $1^{st}$ and $2^{nd}$ dosage are 75% and 25%/total dosage of a single flocculation system. The dewatering efficiency of a dual flocculation system is improved considerably from 10 to 25% under the experimental conditions used herein.

• 한국식품과학회지
• /
• 제10권2호
• /
• pp.209-214
• /
• 1978

Aspergillus nidulans가 생산하는 naringinase의 acrylamide gel을 이용한 고정화(固定化)의 조건과 고정화효소의 성질 및 column reactor의 반응조건을 연구 검토하였는 바 그 결과를 요약하면 다음과 같다. 1. 고정화효소를 제조하는데 acrylamide의 농도는 10%가 적합하였으며, N.N'-methylene bis acrylamide의 농도는 0.5%이상에서 영향이 없었다. 이 조건에서 효소농도는 126 unit/ml가 적합하였다. 2. 고정화효소의 최적반응 pH는 5.0으로서 수용성 효소와 동일하였으며, 최적반응온도는 $50^{\circ}C$로서 수용성 효소에 비해 $10^{\circ}C$상승하였다. 3. Naringinase는 acrylamide gel에 고정시키므로서 pH안정성과 열안정성은 현저히 향상되었다. 4. 고정화효소의 활성화에너지는 수용성 효소보다 약 1/2적은 13.01 kcal/mole이였으며, apparent Km값은 $7.23{\times}10^{-3}$ mole이였다.

• 폴리머
• /
• 제30권4호
• /
• pp.286-292
• /
• 2006

Super water-absorbent resins were prepared by inverse suspension copolymerization of sodium acrylate, acrylamide and 2-hydroxyethyl acrylate using N, N'-methylene-bis-acrylamide as cross-linker. For the suspension copolymerization, monohexadecyl phosphate was employed as the dispersing agent, cyclohexane as the dispersing medium and potassium persulfate as the initiator. The dependence of water-absorption capacity on the amount of crosslinking agent, oil/water ratio, degree of neutralization and the composition of the copolymer were systematically investigated. Furthermore, the swelling kinetics of the super water-absorbent copolymer was carried out. The absorption of the resins is more than 1800 g/g for deionized water and 100 g/g for 0.9% NaCl solution, respectively. The copolymers showed an increased salt resistance and enhanced water retention of soil.

• 한국세라믹학회지
• /
• 제42권3호
• /
• pp.205-210
• /
• 2005

Tetraethyl Orthosilicate(TEOS)를 $SiO_2$ 전구체 용액으로 사용하여 Polyacrlamide gel 방법으로 나노 실리카 분말을 합성하였다. 이 gel 공정법은 비교적 간단한 중합법이며, 고분자 망상구조가 $SiO_2$의 응집을 억제하므로 비교적 낮은 하소온도에서 나노입자를 합성할수 있었다. $SiO_2$ 분말입자의 크기는 gel 전구체중의 ammonium persulphate와 N,N'-methylene-bis-acryamide(BIS)의 농도에 영향을 받았다. 실리카 입자의 크기는 ammonium persulphate의 농도가 증가할수록 작아졌으며 그 농도가 0.01M일때 가장 작은 10nm크기의 입자를 얻었다. 또한 그 입자의 크기는 BIS의 농도가 증가할수록 작아졌으며 그 높도가 0.05M일때 입자의 크기는 5nm였다.

• Fibers and Polymers
• /
• 제5권2호
• /
• pp.95-104
• /
• 2004

A series of superabsorbents based on acrylic acid (AA), sodium acrylate, 2-acrylamido-2-methylpropane sulphonic acid, N,N'-methylene bis-acrylamide (MBA) were prepared by inverse suspension polymerization. These hydrogels were further crosslinked on the surface with polyethylene glycol-600 (PEG-600). The water absorbency or swelling behaviors for these xerogels in water and 0.9% saline solutions, both under free condition and under load were investigated. Absorption characteristics of these hydrogels were found to depend on nature and concentration of crosslinker in the system. It was also found that the saline absorption was significantly improved as the incorporation of AMPS in the polymer was increased. The surface crosslinking introduced in the polymers was found to improve the absorption under load characteristics without lowering the free water absorption capacities of the polymer to a considerable extent.

• 폴리머
• /
• 제37권6호
• /
• pp.794-801
• /
• 2013

Novel microgels of N-isopropylacrylamide (NIPAM)-co-methacrylic acid (MAA) (NIPAM-co-MAA) with different contents of N,N-methylene bis acrylamide (MBA) were prepared by emulsion polymerization technique and were studied by Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and zeta potential measurement. Effect of pH, temperature and different salts concentration on the microgel particles was investigated. DLS results have shown that the hydrodynamic radius of the microgel increased upon increasing pH and decreased upon increasing temperature. The swelling/deswelling behaviors as determined by DLS showed the ionic repulsions of the carboxyl group of the methacrylic acid and hydrophobic interaction of NIPAM. The effect of various salts on volume phase transition temperature (VPTT) was also investigated. Upon increasing salt concentration, VPTT became broad and shifted to a lower temperature. Electrophoretic mobility measurements showed an increase with increasing pH and temperature at a constant ionic strength.

• 한국균학회지
• /
• 제28권1호
• /
• pp.16-21
• /
• 2000

식용버섯 인공재배시 수분조정제로 아크릴아미드와 아릴설폰산염의 공중합물의 가수분해물인 CPAM-AS-hyd-1의 흡수겔을 첨가하여 각종 식용버섯의 균사생장 및 자실체 수량에 영향을 살펴본 결과 배지 100cc에 200g까지의 첨가는 균사생장에 큰 영향을 미치지 많았다. 식용버섯 생산을 위한 흡수겔의 적정 농도는 배지 100 cc에 대하여 느타리버섯의 경우는 200 g, 노루궁뎅이버섯은 $200{\sim}250\;g$, 팽이버섯은 200 g 첨가시 양호하였으며, 팽이버섯 재배시 폴리머 흡수겔과 10%(v/v)의 평화왕겨 첨가가 수량증대에 효과적이었다.