• Applied Chemistry for Engineering
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• v.10 no.8
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• pp.1216-1220
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• 1999

Different amounts of zinc stearate were incorporated as a plasticizer into poly(styrene-co-sodium methacrylate) ionomers prepared by bulk-suspension plymerization and neutralization with sodium hydroxide and effects of the zinc stearate on the thermal and rheological properties were investigated. It was obseved that the crystallization of zinc stearate in the ionomers were partially suppressed depending on the content of ionic moieties. It is postulated that the ionic moieties dissolved zinc stearate and suppressed crystallization of the zinc stearates. We speculated that 0.4~0.6 mole of zinc stearate was dissolved by one mole of the ionic moiety. Poly(styrene-co-sodium methacrylate) containing only the dissolved zinc stearates showed typical rheological properties of homogeneous systems in Cox-Mertz plots. However, poly(styrene-co-sodium methacrylate) containing crystallizable zinc stearates as well as dissolved ones showed typical rheological properties of heterogeneous systems.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.3
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• pp.117-121
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• 2003

Nickel(Ni) powders were prepared from the mixture of nickel chloride and magnesium stearate by a hydrogen reduction process, and the effect of reaction temperature and the addition of magnesium stearate on the chracteristics of the powders were investigated. The effect of size reduction of nickel particles was observed in the presence of magnesium stearate owing to the inhibition of excess growth of paricles. The size reduction and the degree of agglomeration of the particles affected by the amounts of liqiud phase, which related to the increase of magnesium stearate.

• Proceedings of the KSEEG Conference
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• 1999.04a
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• pp.273-275
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• 1999

• Applied Chemistry for Engineering
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• v.3 no.4
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• pp.639-648
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• 1992

For recycling cement hydrate(CH) as waterproofers for mortar and concrete or a filler for rubber & plastics, the cement hydrates were treated with stearic acid(SA). And the bonding characteristics and the water repellency of the CH-SA compounds were investigated by using FT-IR, TGA, SEM, XRD, and contact angle measuring apparatus. Water tightness of the remitars used CH-SA compounds was also tested. The results are summarized as follows : 1) If the cement hydrates are treated with over 2.0% of stearic acid, the CH-SA compounds show very strong water repellency. 2) The stearic acids are solidified on the surfaces of cement hydrate in calcium stearate and aluminium stearate. 3) If CH-SA compounds which is cement hydrate treated with 5~10% of stearic acid are used 3%~6% in remitar, water absorption ratio and water permeatility ratio of remitar are decreased in below 30% of those of the ordinary remitar.

• Tribology and Lubricants
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• v.7 no.2
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• pp.28-35
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• 1991

3원통/링 마모시험기를 사용하여 윤활유 공급하에서 미끄럼 마모시험을 수행하였다. 엔진유에 첨가되는 대표적 첨가제인 ZDDP, 청정제, 분산제의 첨가제 3종과 모델 산호물로서 유성제인 스테아린산을 선택하여, 그 배합유의 마모방지특성을 조사하였다. 청정제 및 분산제 각각의 첨가에 의해 마모방지특성은 향상되었으나, 청정제 및 분산제를 동시에 첨가할 경우 마모방지성능의 향상효과는 없어졌다. 또한, 모델산화물인 스테아린산의 첨가로 인하여 ZDDP의 마모방지작용은 나빠지나, 청정분산제가 그 악영향을 억제하는 작용을 한다.

• Elastomers and Composites
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• v.47 no.3
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• pp.210-215
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• 2012

Whitening phenomena of the EPDM composites with different inorganic filler compositions which were aged at $90^{\circ}C$ for 7 days in air and tap water atmospheres, respectively, were investigated. The aged samples in tap water containing stearic acid exhibited severe whitening phenomena, while all the samples aged in air did not show any whitening. Depending on the filler compositions, there was no big difference in the whitening phenomena. The whitening materials were analyzed using gas chromatography/mass spectrometry (GC/MS), image analysis, energy-dispersive X-ray spectroscopy (EDX), and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The whitening materials were identified to be salts of stearic acid. The salts of stearic acid were formed by reaction of metal cation in tap water and stearic acid in the sample.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.3
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• pp.131-135
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• 2008

This study is to establish the coating technique for synthetic mica and to prepare synthetic mica with the non-aqueous property. The surface coating of synthetic mica is prepared with stearic acid using the high speed stirrer. The characterizations for mica powders coated the stearic acid are carried out by the deposition test, XRD and SEM. The results of research could be coated the stearic acid on the mica by 1600 rpm/min at $70^{\circ}C$ for 10 min. From the observation of SEM was found that the non-aqueous property mica could obtained by mixture ratios for stearic acid and mica, the inner temperature and rotation speed of the stirrer but treated time be unrelated.

• Applied Chemistry for Engineering
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• v.26 no.1
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• pp.86-91
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• 2015

The MPPO (3-methyl-1-phenyl-2-phospholene-1-oxide) was prepared by using various polymerization inhibitors such as BHT (2,6-di-tert-butyl-4-methylphenol), TBC (4-tert-butylcatechol), and copper stearate. The MPPO was confirmed by the analysis using FTIR, $^1H$-NMR, and GC/MS regardless of the type of inhibitors. The yield of MPPO increased with the increase of reaction time, whereas the purity of MPPO decreased slightly. The yield and purity of MPPO increased with temperature, but the MPPO prepared by using copper stearate as a polymerization inhibitor exhibited no changes in the purity. The amount of inhibitors had no effect on the yield of MPPO. The purity of MPPOs increased with the amount of inhibitors, but the MPPO prepared by using BHT showed no changes of the purity. We found that the MPPO prepared by using copper stearate exhibited the highest catalytic activity for diphenylcarbodiimide synthesis.

• 월간산업보건
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• s.60
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• pp.40-41
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• 1993

산업위생의 진보에 따라서 전형적이면서 중증인 만성직업병은 일부의 예외를 제외하고는 근래에 거의 발생되고 있지 않다. 그러나 급성 특히 재해성인 것은 그 발생원인이 다분히 우발적인 것이어서 만전을 기한 예방대책이 곤란한 경우도 있기 때문에 지금도 많은 발생사례가 있으며, 또 앞으로도 발생될 가능성이 충분히 있다. 또한 근래의 산업이 발전함에 따라 그 독성이나 중독증상이 불명확한 물질을 사용하게 되었고, 이로 인해 샐운 직업병이 발생되게 하였다. 이러한 직업병 발생사례 중 주목해야 할, 혹은 각 사업체에 있어서 향후 예방대책의 참고자료가 되는 것이 일본 노동성 노동위생과에 의해서 정리되었다. 이글을 참고자료로 하여 향후의 재해방지에 도움이 되고자 한다. <편집실>

• YAKHAK HOEJI
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• v.38 no.6
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• pp.654-663
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• 1994

Lipiodol-anticancer suspensions containing fluorouracil, tegafur, mitomycin C, methotrexate, or adriamycin were prepared by Shinohara method using aluminum monostearate as a dispersing stabilizer. Lipiodol-suspension showed thixotropic property when the concentration of aluminum monostearate was above 2%. Observed thixotropic area which reflects the extent of thixotropic breakdown indicated that the thixotropic property of Lipiodol-suspensions maintained for six weeks in a refrigerator$(4^{\circ}C)$. Lipiodol-anticancer suspensions containing 2% aluminum monostearate maintained a more stable suspension system compared with simple mixtures and Lipiodol-anticancer suspensions without aluminum monostearate. As the concentration of aluminum monostearate increased, the drug release from Lipiodol-anticancer suspensions was more retarded.