Molecular orbital calculation based on the orthogonal atomic orbitals has been carried out on seven methyl α, β -unsaturated carboxylates in order to elucidate the remarkable differences in their reactivity as dienophiles in the Diels-Alder addition to methyl trans-9, trans-11-octadecadienoate shown in Table 2. Calculated results are summarized in Table 1. It is found that the frontier electronic densities of the highest occupied orbitals at the reaction centers have a good linear relationship with the logarithm of the rate constants. Plots of the correlation for dicarboxylates and for monocalboxylates fall on two different but parallel lines as shown in Fig.1. The correlation of the chemical reactivity with the electronic structure has been discussed on the basis of the experimental results.

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Making use of a commercial conduction type calorimeter, we constructed a solution microcalorimeter which is applicable to entropy titration involving reactive reagents difficult to handle in the air, and tested its performance. The heats of coordination of various organic bases (amines, pyridines and ethers) to triethyl-aluminium were measured with the aid of this apparatus. As to the equilibrium constants of coordination, only approximate values could be estimated from the thermometric titration curves, because they were too large for exact analysis. The value of the enthalpy change of each system was obtained from the thermometric titration curve as a mean value of several titrations of a base solution fairly before the equivalent point. Comparing the enthalpy changes thus obtained with the pKa values of the bases used, it was found that linear relations hold individually for amines and ethers, but pyridines form an iso-lated group apart from the other series (cf. Fig. 5). The chemical shifts of methyl and methylene protons of the ethyl groups bonded to aluminium were calculated from the NMR spectra of the coordination compounds. Then, the internal chemical shift, defined as a difference between those of methyl and methylene protons, can be correlated with the electronegativity of aluminium in the coordination compounds according to the Dailey-Shoolery equation (cf. Eq. (7)). As a result of comparison of the enthalpy changes with the values of the electronegativity thus obtained, it was shown that a simple linear re-lation holds throughout, with the only exception of pyridines which exert a marked shielding effect due to the ring current to the methylene proton (cf. Fig. 7).

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The desensitizing phenomena of phenosafranine (dye I ), 9-methylthiacarbocyanine (dye II) and 3, 3'-disulfopropy1-5, 5'-dichloro-9-ethylthiacarbocyanine (dye III) were studied. Dye I has been reported to show the desensitization acting as an electron acceptor, and dye II the desensitization acting as a halogen acceptor, and dye III scarecely shows desensitization. These dyes were introduced into coated emulsions by bathing the latter in the solutions of these dyes before or after exposure, in order to observe their desensitizations due to the depression of latent image formation and those due to the depression of development process separately. Only dye II showed the desensitization due to the depression of development process, which might arise from the difficulty of desorption of dye If from silver bromide grains owing to its gregate formation. However, in the cases of dyes I and II, the desensitization was found to come from the depression of latent image formation. The desensitization was strong for both surface speeds and internal ones even at the levels of small dye amount in the case of dye I, and was strong for surface speeds at the levels of large dye amount in the case of dye II. These observation are thought to be consistent with the proposed mechanism of the desensitizations by these dyes.

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The mechanism of photographic effects of hexachlororhodate (III)[1] at AgBr and AgBrl grain surfaces was studied. Compound [1] markedly decreased both surface and internal speeds of AgBr grains. By bathing coated emulsions in the aqueous solution of [1] before and after exposure to light, it was confirmed that the above desensitizing phenomenon resulted mainly from the depression of latent image formation by [1]. The desensitization by [1] was competitive with that by phenosafranine, which is known to act as a trap for photo-electrons in silver halides. Although [1] decreased photographic speeds of the grains in which the ratio of internal speed to surface one was small (primitive AgBr), [1] increased those of the grains in which the ratio was large (primitive AgBrl). The effect of [1] upon the electronic process in AgBr grains was confirmed by observing that the emission of the grains at about 600 nm at liquid nitrogen temperature was markedly quenched by [1]. The above-mentioned results support the consideration that (1) acts as a trap for photo-electrons causing photographic sensitizing and desensitizing phenomena at the surface of AgBr and AgBrI grains.

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To clarify the disproportionation of tungsten subchlorides in detail, the behavior of tungsten dichloride and tungsten tetrachloride on heating in. an argon atmosphere was examined by thermal gravimetric, differential thermal and X-ray analyses. The behavior of the tungsten subchloride which was obtained by heating tungsten tetrachloride at 380° C in an argon atmosphere, and might be represented by an empirical formula of WCl2.6, was also examined. TGA and DTA curves of the dichloride on heating are shown in Fig.1. The dichloride begins to disproportionate to tungsten and the gaseous tetrachloride at about 505° C. TGA and DTA curves of the WCl2.6 which was newly found to exist in this work are shown in Fig.4. The WCl2.6 begins to disproportionate to the dichloride and the gaseous pentachloride at about 395° C. Then the dichloride formed disproportionates in the same way as described above. TGA and DTA curves of the tetrachloride on heating are shown in Fig.2. The tetrachloride begins to disproportionate to the WCl2, 6 and the gaseous pentachloride at about 295° C. Subsequently, the WCl2.6 formed disproportionates to form the dichloride. Then the dichloride formed disproportionates in the same way as described above. X-ray diffraction data of WCl2.6 are also shown in Table 1.

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The reduction process of tungsten dichloride, tungsten tetrachloride, tungsten pentachloride, and tungsten subchloride which might be represented by an empirical formula of WCl2.6 with hydrogen was examined by thermal gravimetric and X-ray analyses. TGA curve of dichloride is shown in Fig.1. Dichloride was reduced with hydrogento tungsten above 380° C. TGA curve of WCl2.6 is shown in Fig.2. WCl2.6 was reduced with hydrogen to tungsten via the dichloride above 315° C. TGA curve of the tetrachloride is shown in Fig.3. The tetrachloride was reduced with hydrogen to tungsten via WCl2.6, the dichloride above 270° C: The reduction was accompanied by the disproportionation of 13.0% of the tetrachloride with the formation of WCl2.6 and the gaseous pentachloride above 295° C. The WCl2.6 formed was then reduced with hydrogen in the same way as described above. TGA curve of the pentachloride is shown in Fig.5. The pentachloride vaporized above 105° C. The vaporization was accompanied by the reduction of 17.7% of the pentachloride to the tetrachloride with hydrogen. The tetrachloride formed exhibited the same behavior as described above.

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The solid state reaction in the MgCl2.6H2O-α -Al2O3 system was carried out and the promoting action of MgCl2 on the formation of MgAl2O, was discussed. Firstly, the mixed powders of α -Al2O3 and MgCl2.6H2O were heated up to about 600° C in air. In this process, MgCl2.6H2O was decomposed to MgO and MgCl2. Then, the MgO- MgCl2-α -Al2O, mixture obtained above was treated isothermally in the temperature range of 650-925° C. The extent of conversion to MgAl2O4 was measured by means of chemical analysis and X-ray diffraction analysis. Kinetic data were fitted to the diffusion-controlled Jander's equation (Fig.7). The curve of log k vs.1/T was divided into two regions. E was 70 kcal/ mol in the lower temperature region and 20 kcal/mol in the higher temperature region. In both regions, active MgO was obtained during the thermal decomposition of MgCl2.6 H2O. Furthermore, in the high-temperature region, the formation rate of MgAl2O4 was considered to be promoted greatly by molten MgCl2. In order to examine actions of molten MgCl2, the model experiments by the use of MgO and α -Al2Os pellets were made in vacuum (Fig.1). Table 1 shows the weight change of two pellets after reaction. Fig.9 and Fig.10 show the X-ray diffraction pattern of the reaction surface of two pellets. These results suggest that MgO dissolved in molten MgCl2 spread uniformly over the surface of α -Al2O3 particles, then MgO is transported to the inner part of α -Al2O3 particles and rapidly reacts with α -Al2O, crystallites to form the spinel-layer through which the counter diffusion of Mg2+ and Al3+ occur (Fig.11). This reaction model was supported by the observations of the optical microscope (Fig.12) and the scanning electron microscope (Fig.13).

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A rapid and nondestructive method is required for the determination of tungsten in various compounds. We have studied fast-neutron activation analysis for this purpose, because the existing techniques are time-consuming. The short-lived 183mW formed by the process 73mW has proved to be utili satisfactorily for this method. The lowering of its precision due to -Able variations in experimental conditions, especially to the fluctuation of the neutron flux during the irradiation, has been found to be minimized by the use of bromine as an internal standard material. Since the half-life of formed by the process Br(n, n')7'rnBr is a the same as that of 1. W, the induced activities of the both nuclides can be regarded as pr.- ional regardless!, of the experimental conditions. In the five-cycle irradiation met a straight line has been obtained as a calibration curve for tungsten contents from 50 to 200mg, with the relative error of less than 2.0%. This technique will provide a useful method for the determination of tungsten.

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The addition of bromine to 3, 3-dimethyl-1-cyclobutene-carboxylic acid [1 a], alkyl 3, 3- dimethyl-1-cyclobutene-1-carboxylate ([1 b] R=CH3, [1 c] R=C2H5, [1 d] R=CH(CH3)2), and 3, 3-dimethyl-1-cyclobutene-1-carbonitrile [1 e] gave trans and cis isomers of 1, 2-dibromocyclobutane derivatives in the trans/cis ratio of about 2: 1, 2: 1 and 9: 1, respectively. The isomers prepared from bromine addition to substrates [1 b], [1 c] and [1 d] have been separated in pure state and the stereochemistry(cis or trans) of these adducts was estimated on the basis of the reluctance of HBr elimination reaction with pottassium hydroxide. NMR spectra of stereoisomers revealed an interesting phenomina of restricted rotation of the carbonyl and isopropoxy groups in the trans isomers. The probable reaction path of these addition reactions was also discussed briefly.

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Theepoxidatianreactionofconjugateddieneswithperbenzoicacidinchloroformwasexzminedkinetically. Ethylsorbate, butadiene, isoprene, trans-1, 3-pentadiene, 2, 3-dimethylbutadiene, 4-methyl-1, 3-pentadieneand2, 4-dimethyl-1, 3-pentadienewereusedasconjugated dienes. Fortheepoxidat onofbutadienederivatives(C=C-C=C)giving1, 2-epoxy-3-butenes, allnearHammett-typerelationwasconfirmedwhenOkamoto-Brown'ssubstituentconstant σ ρ +wasapphedto1-, 2-and4-substituent, andσ m+wasappliedto3-substituentasshown inFig.4. Thevalueofρ was-3.83.

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5, 6, 7, 8-Tetrafluoro-2, 4-quinolinediol [4] has been prepared in ca.30% yield by the inframolecular condensation of methyl N-acetyltetrafluoroanthranilate [3] by means of sodium in boiling toluene. Another possible route to [4] which involves the fusion of malonyl bis(tetrafluoroanilide) [7] with a mixture of aluminum chloride and sodium chloride gave only a product in which fluorines were partially replaced by chlorine. Four yellow azo colors were prepared by coupling diazotized aniline or m-substituted anilines with [4]. The visible absorption spectra of these colors were compared with those of the corresponding fluorine-free colors (Table 1 and Fig.1, 2). The tetrafluoro colors using aniline or toluidine as diazo component showed batho- and hyperchromic effect. On the contrary, the electronegative chloro or nitro group in the diazo component shifted the absorption hypochromically. No improvement in light fastness was observed by the introduction of fluorines into color molecules.

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The reaction of isatoic anhydride [1] with amines was carried out to synthesize several new heterocyclic compounds. The reaction of [1] with benzamidoxime gave N-hydroxyiminobenzyl-2-aminobenzamide [2].5-(o-Aminophenyl)-3-phenyl-1, 2, 4-oxadiazole [3] was obtained by the ring closure reaction of [2] with base or acid. The acetylation of [3] gave 5-(o-acetylaminopheny1)-3-pheny1-1, 2, 4- oxadiazole [4], which was also prepared directly by the reaction of [2] with acetic anhydride. The condensation of [2] with formaldehyde in methanol gave 2, 3-dihydro-3-hydroxyiminobenzyl4(1 H)-quinazolinone [5]. The reaction of [1] with N'-chlorobenzamidine and guanidine gave 2-phenyl-4(3 H)-quinazolinone [6] and 5 H-quinazolino[3, 2-a] quinazoline-5, 12(6 H)-dione [7], respectively. The reaction of [1] with aminoacetal gave o-amino-N-(2, 2-diethoxyethyl)-benzamide [8], which was converted into 3 H-1, 4-benzodiazepine-5(4 H)-one [9]. The reaction of [1] with glycine ethyl ester gave directly 3 H-1, 4-benzodiazepine-2, 5(1 H, 4 H)-dione [10]. And the reaction of [1] with carbonohydrazide and malononitrile gave 1-anthraniloylcarbonohydrazide [11] and 2-amino-3-cyano-4(1 H)-quinolone [12], respectively.

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The reaction of the benzylmagnesium chloride with chloromethyl methyl ether has been studied in detail using various solvents. Five products have been obtained: 2-phenylethyl methyl ether [1], o-[2] and p-methylbenzyl methyl ether [3], and o-[4] and p-(2-methoxyethyl)benzyl methyl ether [5]. The results obtained show that the formation of abnormal products is suppressed with increase in solvent basicity and in the ionic character of the metal in the order of C-Li> C-Mg> C-Al. The intermediate responsible for the formation of diether [5] was characterized by trapping it through the reaction with gaseous formaldehyde.

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Solvolyses of 2, 3, 4-tri-O-acetyl-α -D-xylopyranosyl [1-o] and xylothiapyranosyl [1-s] bromides in methanol, ethanol and 2-propanol were investigated. Both bromides were solvolyzed through SN1 process (Table 1 and 2). The rate of 2-propanolysis of [1-o] was strongly increased in the presence of added bromide ion (Table 3), and the product analysis showed the presence of considerable amout of α -xyloside, while bromide ion exhibited no such rate acceleration and enhanced production of the α -xylosides in methanol and ethanol (Table 4). Mechanism for 2-propanolysis of [1-o] was discussed, which involved a) the nucleophilic attack of bromide ion to the anomeric carbon atom of [1-o] to give the β -bromide [5], and b) successive solvolysis of [5] via acetoxonium ion intermediate to α - and β -xylosides. Analysis of alcoholysis product mixture from [1-s] showed the α /β -xyloside ratio of more than unity.

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Decenoic, dodecenoic and tetradecenoic acid were separated in pure state from the seed oil of Litsea glauca Sieb. by means of silver nitrate silica gel chromatography. The position of the double bond at Δ 4 was determined in terms of the fact, that the resulting acids were succinic and the corresponding saturated C6-, C8- and C10-acid as described in Table 1, when methyl alkenoates were oxidized with KMnO4 according to Armstrong and Hilditch, and also in terms of their NMR spectra, which showed an apparent strong doublet at 7.65 γ and a multi plet centered at 4.57 γ. Presence of the broad absorptions centered at 720 cm-1 and absence of the absorptions at 965-970 cm-1 in the IR spectra of the acids, indicated in the above title, showed that their double bonds take the cis-configuration. The physical constants of the acids, indicated in the above title, their p-bromophenacyl esters and p-phenylphenacyl esters were compared with those of the trans-alkenoic acids of the same carbon atoms, which were previously prepared by M. Iwakiri and with those of the obtusilic, linderic and tsuzuic acid, which were separated from the seed oil of Lindera obtusiloba, Bl. by S. Komori and S. Ueno.

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Glucose oxidase (β -D-Glucose: oxygen oxidoreductase E. C.1.1.3.4) was entrapped in polymer matrix, cross-linked poly-2-hydroxyethyl methacrylate, to obtain insoluble enzyme. The optimum time for polymerization in entrapping the enzyme was found to be 4 hr at 20° C. The enzymic activity of the insoluble one was independent of polymerization initiator, riboflavin, ammonium peroxodisulfate, potassium peroxodisulfate and of carrier, 2-hydroxyethyl methacrylate. However, the particle size of the insoluble one and concentration of cross-linking agent had an influence on enzymic activity. The concentration of cross-linking agent that gave the highest activity was 15 mol percent (N, N'-methylene bisacrylamide in a 0.1 mole of the monomer). The behaviors of the enzyme entrapped in various polymers were investigated by measuring the values derived from elution of enzyme from polymers, from dynamics and from kinetics. Both the enzyme and co-enzyme (FAD) were not eluted from the particles with low concentrations of the cross-linking agent (0-10 mol%). However, Michaelis constants depended on the particle size. On the other hand, it was observed that the enzyme and coenzyme (FAD) were eluted from the particles which were polymerized with high cross-linking agent (10-20 mol %). The Michaelis constants remained constant in these particles. Interactions between synthetic polymers and enzyme were observed to be strong in the particles with low concentration of crosslinking agent.

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Two types of the a (helical chain) and the β (planar zigzag chain) crystal phases have already been found in oriented samples of poly(p-ethyleneoxybenzoate) (PEOB). Dynamic mechanical, X-ray diffraction, birefringence and electron microscopic techniques were employed to determine the mechanisms or processes of the α → β crystal phase transition upon stretching above the glass transition temperature (80° C). The following results were found for the α → β crystal phase transition of PEOB. (1) Since there is no change of degree of crystallinity during phase transition caused by stretching, the α → β phase transition proceeds with the mechanisms of crystal-crystal transformation. (2) The β phase volume fraction converted from the a phase is proportionally correlated with the applied stress whereas the applied strain is not an important factor for determining the β phase volume fraction. (3) According to the morphological observation, the super structure of drawn PEOB is referred to the mechanical two phase model in which tie link constrains two neighboring crystalline parts. (4) According to the measurements of orientation, amorphous chains are not constrained and almost randomized upon stretching above the glass transition temperature. (5) The values of modulus, calculated on the assumption that stress is selectively concentrated on the tie link of the mechanical two phase model and that the α → β crystal phase transition occurs in this tie link, are found to be in good agreement with the observed values of modulus at various temperatures. From these results, it was concluded that the α crystal phase of PEOB transforms to the β crystal phase selectivily in tie link region as a consequence of stress concentration during stretching above glass transition temperature.

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The Ultrasonic absorption in solutions of poly(vinyl propionate) and poly(vinyl butyrate) in toluene were measured by the pulse method in the frequency range 1-60 MHz and in the temperature range 0-60° C. The ultrasonic absorption of PVPr was represented by the single relaxation equation, while that of PVBu by the double relaxation equation. The relaxation of PVBu of lower frequency was ascribed to the rotation of side chains around the main chain, and that of higher frequency to the local rotation of side chain itself. The experimental results were discussed on the basis of the 2-state model.

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In a previous paper, we described that the polymerization of methyl methacrylate (MMA) were occured by collagen in the presence of water. In the course of our further research on the collagen initiated polymerization of MMA, the reaction conditions on the yield of polymer have been studied. When the materials were charged into glass tube in the following order: collagen fiber (1 g), water (20 ml) and MMA (5 ml), and then the polymerization was carried out at 85° C for 2.5 hrs, the yieled of the polymer was 77.2%. In the absence of water, the polymerization did not occur. The yield of the polymer decreased by using collagen fiber which was swelled in either water or MMA for 20 hrs before the polymerization. The yield of the polymer was not influenced markedly by emulsifiers in the system. The yield of the polymer varied significantly with the change of pH. The plots between the pH value in the system and the yield of the polymer showed the bell-type curve: maximum yield was obtained in about 3 of pH, the yield decreased with the increase of pH and then increased slightly in alkali region from 8 to 9 of pH. The feature was quite similar to that of plots between the pH value and the degree of swelling of an ox-skin which was reported by Court. It was suggested that the yield of the polymer may be related to the swelling of collagen fiber.

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The polymerization of styrene initiated by azobisisobutyronitrile (AIBN) were carried out at 60° C in five kinds of halogenated hydrocarbon solutions. The rates of polymerization (R_p) in solutions which contained 50 vol % styrene were increased in the following order of solvent: 1, 2-dichloroethane<chlorobenzene<bromobenzene<1, 1, 2, 2-tetrachloroethane<o-dichlorobenzene. The rates of initiation of polymerization (R_t) in solvents were determine by using benzoquinone as inhibitor and then the values of δ²(=k_t/k_p²) werecalculated from the equation: δ²=. R_t. (M)² /R_p². The values of R_t hardly changed with the nature of solvents, while the values of δ² changed markedly and showed preferably to, depend on the inverse of viscosity of the styrene-solvent system. Efficiencies of initiation of polymerization (f) in solvents were calculated from the equation, f= R_t /2 k_d(AIBN), where kd is the rate of decomposition of AIBN in solvents. There was a positive correlation between the k_d value and the dielectric constant of solvents, which was reported in previously. The values of f decreased with an increase of viscosity of the system. It was found that the polymerization of styrene in these solvents is still more sensitive than that is commonly supposed on the viscosity of system. t Solvent Effects in Radical Reactions. II.

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The preparative reaction of highly phosphorylated poly(vinyl alcohol)(PVA) by means of ureaphosphoric acid-dimethylformamide(DMF) system has been studied. Phosphorylation was accelerated by urethanization of PVA occurred as side reaction. The addition of triethylamine was also effective for phosphorylation. Therfore, the most effective procedure of phosphorylation was as follows: PVA was first urethanized in urea-triethylamine system, and then phosphorylated by adding phosphoric acid. According to this method, approximately 100% of effective hydroxyl groups in PVA could be phosphorylated. The reason why the urethanization has been effective for phosphorylation was that the urethanization brought about an increased solubility of PVA in the reaction medium.

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Aqueous solutions of poly(vinyl alcohol) (PVA) containing isopropylalcohol, glycerol, or sucrose, were irradiated with high doses of γ -rays. After irradiation, water-swelling ratios and watersoluble fractions of the polymeric products were determined. When glycerol or sucrose was added, highly hydrophilic derivatives of PVA were formed. They were found to contain a few mole-percents of glycerol or sucrose. Intrinsic viscosities of these derivatives decreased at initial stages of irradiation and then increased to gelation. This may be explained by assuming that, due to the formation of these derivatives, intermolecular crosslinking of PVA was restrained.

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2, 6-Xylenol (XOH) was polymerized by the copper-polyvinylpyridine (PVP) chelate in heterogeneous systems. The catalytic characteristics of insoluble Cu-PVP complexes were discussed. Insoluble Cu-PVP complexes underwent relatively rapid exchange of ligands to give catalytically active structures. For example, active CuCl(OH)-PVP complexes were obtained when inactive CuC12-PVP complexes were washed with water. XOH was polymerized by the swelled Cu-PVP complex in benzene. After polymerization, the catalyst was readily recovered by filtration in a high yield and the catalyst so recovered could be used repeatedly. The PVP complexes were relatively stable against alkali due to their chelate structure. In alkaline solution the polymerization was accelerated, while side-reactions were suppressed.

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Formation constants for poly(vinyl alcohol)(PVA)-copper(II) complexes were measured by using a modified Bjerrum's method proposed by Gregor and co-workers. The effects of the ratio Teu₂₊/T_HL(the ratio of the total concentration of copper(II) ion to the concentration of the ligand), nature of anion in copper(II) salts and degree of polymerization of PVA on the formation constants were studied in the system of ionic strength 0.1 at 25° C. In all cases, the formation curves of complexes showed that four hydroxy groups combined with one cuprous ion in the pH range above 7.0. The value log b₁, log b₂, log B of PVA-copper(II) complexes increased with increasing Tcu₂₊/T_HL in the range higher than 0.031 (Fig.8), but were unaffected bythe degree of polymerizationof ligand in the range from 400 to 1400. The formation constants increasedin the order of the anion NO₃^-> Cl^-> SO₄^2-, probably because of the complex formed which involved hydrated copper(II) ion(Table 1). The changes of entropy, enthalpyand free energy in the above reaction were determined by the method of Ringbom(Table 2).

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New photochromic monomer 1, 3, 3-trimethylindolino-6'-nitro-8'-methacryloyloxymethylspirobenzopyran was synthesized. Photochromic polymers containing spiropyran unit were obtained by homopolymerization of this monomer or copolymerization of it with styrene or methyl methacrylate as shown in Table 1. Photochromism of polymeric spiropyran in solution was studied. Absorption spectra of P(St-MSP)--1 in benzene at room temperature are shown in Fig.1. Absorption maxma (_??_) of colored kinds in visible region were influenced by the kinds of comonomer unit. These results are summarized in Table 2. This may be due to the solvent effect of polymer chain. The influences of comonomer unit and solvent on Aymasx was related to the role of them in the solvent effect on spiropyran unit. Fading of colored kinds of low molecular weight spiropyran in solution proceeded with the first order reaction. But those of polymeric spiropyran proceeded with the combined first order reactions as shown in Fig.4-1 and Fig.4-2. This specific behavior of polymeric spiropyran was interpreted in terms of the solvent effect and the steric hindrance of polymer chain. Photochromism of polymeric spiropyran in film was very different from that in solution. _??_ in film are shown in Table 2. But these results are different from the values expected from those in solution. Colored kinds of polymeric spiropyran in film faded quickly at initial stage but slowly at final stage. But they had slower fading rates in film than in solution.

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As an application of fractionation of copolymers by means of thin layer chromatography (TLC), the experiment on the column absorption chromatograph of copolymers was undertaken and the accompanying problems have been studied. The samples used were styrene butadiene copolymer (SBR) with carious molecular weight and styrene content. Mixtures of various solvents were tested on TLC plate to find relevant developer for TLC ans found that the mixture of cyclohexane and benzene was suitable. Typical chromatograms are shown in Fig.2. Molecular weight of the samples was found to be independent of an Rf value. Absorption and desorption experiment of the samples onto silica gel in the developer was also performed to find the loss of weight of the desorbed material. Approximately 70% og weight recovery was observed. The molecular weight distribution and the styrene content of the recoverd fractions were compared with those of the original material. On the basis of the fact that no difference was found between those values, the composition of the sample can be deduced from the analy-sis of the recovered fractions. An idea of multilayer absorpotion or desorption mechanism was proposed to understand the experimental result. Samples were then subjected to cplumn ab-sorption chromatography under the same condition as TLC described above. In this case, samples were prepared by mixing two fractions with different styrene content in the end fractions were observed as expected. Analytical result of styrene content in fractions was normal just before the reversal occurred. Two different SBR, polymerized in emulsion or in solution were choromatographed by this method and the respevtive composition distribution curves were ob-tained. For the former the shape of distribution cureve was broad while for the later it was sharp.

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The relationship between the amount of water vapor supplied for observing hygroscopic process of potassium halides and changes in the surface area of their powders has been studied. The values of water vapor pressure at which the surface area of the sample powders began to change were determined to be 50 and 40% rH for KBr and KI, respectively. The adsorption isotherms obtained about the concerned salts showed that the water molecules were adsorbed in four or five layers at the respective vapor pressure. It is considered that such amount of water absorbed is necessary for the dissolution of the salt.

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Ethyl trans-α -cyano-β -(o-tolyl)acrylate [1] was prepared by Cope-Knoevenagel condensation. Ethyl α -cyano-β -methyl-β -mesityl acrylate [2] could not be obtained by Cope-Knoevenagel condensation from 2, 4, 6-trimethylacetophenone, because its ketonic properties decreased due to the steric hindrance. Then, we prepared [2] in the following way. After ethyl trans-α -cyano-β -mesityl acrylate [3] had been prepared by Cope-Knoevenagel condensation from 2, 4, 6-trimethylaldehyde, [2] was prepared by methylation of [3] with diazomethane. Spectral data of [1] and [2] are shown.

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