Volume 15 Issue 3

  1. Won, Yeong-Moo;Takashi Fukutomi;Toshio Kakurai;Tatsuya Noguchi 109
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    The mechanical degradation of poly (${\alpha}$-methyl styrene) in several mixed solvents (toluene-n-butyl alcohol, toluene-sec-butyl alcohol, toluene-kerosene, toluene-methyl ethyl ketone), from $1^{\circ}C to $45^{\circ}C$, was studied using the capillary flow method. The velocity constant of scission reaction (k) and the limited degree of polymerization (g) were compared at the same value of [${\eta}$] at each temperatures. As results, mechanical degradation of polymer in dilute mixed solutions is affected by composition of solvents around the polymer chains.
  2. Jin Soon Chong;Nung Min Yoon 117
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    Possibility of two phase reduction of carbonyl compounds to the corresponding alcohols was studied. Thus the 0.5 M ether solutions of the representative carbonyl compounds were treated with alkaline stabilized sodium borohydride aqueous solution at room temperature. Butyraldehyde was reduced rapidly within one hr., whereas other aldehydes tested; heptaldehyde, benzaldehyde, and 1-naphthaldehyde were reduced in 6-12 hr. 2-Heptanone was reduced much slowly; 87% in 48 hr., however, acetophenone was reduced moderately; 92% in 12 hr. and cycloalkanones were reduced rapidly (cyclohexanone in 0.5 hr., and cyclopentanone in 3-6 hr.).
  3. Suck-Ju Hong 121
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    Tere-and Isophthalohydroxamoyl chlorides were condensed with 1, 4-benzoquinone to afford quinone type polymer with the oxidation of the ring structure. Similarly, tere-and isophthalohydroxamoyl chlorides were condensed with tere-and isophthaldioximes and terephthalonitrile to give crystalline polyphenylene-1,2,4-oxadiazoles, among which the reaction product of terephthalohydroxamoyl chloride with terephthalonitrile in xylene afforded the highest crystallinity.
  4. Joo Hwan Sohn;Chong Woo Nam;Yu Ok Kim 127
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    To obtain the various kinds of inosose stereomers, the process of electrochemical oxidation is more effective than chemical oxidation of myo-inositol. So that myo-inositol aqueous solution was electrolyzed by platinum and lead peroxide anode to confirming the occurrence of electrochemical oxidation. The result is that myo-inosose-2 is producing with high yield comparatively by electrolytic oxidation of myo-inositol. Also we studied about the relation between the electrolytic current efficiency and electrolytic temperature and anodic current density. The current efficiency is rising with lowering of electrolytic temperature identically in both anode such as platinum and lead peroxide and also rising with increasing of anodic current density in platinum anode, but inversely in lead peroxide.
  5. Hyungsuk Park 133
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    액체구조의 천이상태이론을 이성분용액의 액체-증기 계면에 적용하여, $C_6H_{12}-C_6H_6$ $CCI_4-C_6H_6$, $CHCl_3-C_6H_6$, $CHCl_3-CCl_4$, $CCl_4-CS_2$계의 표면장력, 표면흡착량, 표면에서의 활동도 계수들을 계산하였다.
  6. Byung Kak Park;Mu Sang Lee;Young Suek Hong 147
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    On the baisis of the calculations by the two centre Huckel method for sigma electron system, the electronic structure of the various aliphatic amines including ammonia, and the relationship between the observed $pK_b$ and the change in the sigma electronic energy, ${\Delta}E{\sigma}$ in the course of protonation are discussed. A parallelism is observed between the $pK_b$ and the calculated ${\Delta}E{\sigma}$ of the amines. Also, it is observed that the electron densities of hydrogen atom directly bonded to nitrogen of the amines, likewise have a linear relationship with the $pK_b$. Therefore, the basicity of the aliphatic amines may be estimated qualitatively by means of the two center Huckel method.
  7. Woon-Sun Ahn;Seihun Chang 153
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    이성분용액의 표면을 단분자층 또는 다분자층으로 가정할 때의 표면장력식을 통계열역학적으로 유도하였다. 이 표면장력식들은 Gibbs흡착식을 만족시켜 주며, 따라서 표면에서의 흡착을 계산할 수 있다. 또한 이때 얻은 bulk용액의 화학포텐샬이 열역학적으로 유도된 것과 같다는 것을 보였다.
  8. Byung-Rin Cho;Young-Ja Lee;Ikchoon Lee 159
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    The relative viscosities ${\eta}_r$ of a series of homologous tetraalkylammonium chlorides $Me_4NCl,\;Et_4NCl,\;Pr_4NCl\;and\;Bu_4NCl$ in a series of isopropanol-water mixtures have been determined at $30^{\circ}C$ using Ubbelohde-type viscometers. The viscosity data have been interpreted in terms of viscosity A-and B-coefficients calculated from the Jones-Dole equation, ${\eta}_r=1+AC^{1/2}+BC$. The results indicate that the structure-breaking effect of chloride ion is maximum at 0.l~0.15 mole fraction isopropanol, while the size effect(Einstein effect) of the larger $R_4N^+$ ions is maximum at 0.2~0.25 mole fraction. The results also indicate that in aqueous and water-rich solutions the larger $R_4N^+$ ions (e.g. $Pr_4N+, Bu_4N^+$) appear to be excellent structure-formers and that the viscosities of solutions is not strongly affected by the electrostriction effect of chloride ion.