There are many kinds of industrial processes for the production of aliphatic tertiary amines, especially N, N-dimethylalkylamines which are very important intermediates for producing cationic surfactants, amphoteric surfactants, and amine oxides. Among them, catalytic amination of aliphatic alcohols is the simplest process and can produce N, N-dimethylalkylamines with high qualities. In this process, amination catalysts are very important and have been examined over a long period of time by various researchers. The abilities required for the amination catalysts are dehydrogenation and hydrogenolysis abilities in consideration of the amination mechanisms of aliphatic alcohols, and a lot of complex catalysts based on copper catalyst have been studied to satisfy these abilities. Then the performance of copper-nickel amination catalyst which the authers had researched and developed are presented as the example of complex catalysts.
Recently, high solids coatings are widely used in the industrial coatings fields, especially in automobile coating field, in the United States. In Japan, the use of high solids coationgs has been gradually increasing. Since the melamine cured high solids coatings usually consist of the oligomeric polyol resin, low molecular weight melamine resin and sulfonic acid catalyst, it is very important to elucidate the influences of molecular weight of oligomer and curing mechanisms on the film appearance, such as sagging and the orientation of aluminum pigment, and also on the film properties. In this paper, recent works on the developments of the raw materials for high solids coatings including acrylic oligomers, polyester oligomers and rheology control agents were reviewed. Then the recent works on the basic problems of high solids coatings, such as rheological properties of oligomer solution, prediction of solution viscosity, viscosity behavior during thermal curing, reaction mechanisms of hexamethoxymethylmelamine, mechanical properties and weathering properties of cured films were reviewed.
The pyrolytical characteristics of various deteriorated oils were investigated by thermogravimetry(TG), derivative thermogravimetry (DTG)and differential scanning calorimetry (DSC). These oils were prepared as follows:soybean oil and lard were heated at 60°C to obtain autoxidized oil and 180°C to obtain thermally oxidized oil, and deteriorated oil was obtained by frying chicken in shortening, The relationship between the pyrolytical characteristics and chemical deterioration was also studied. 1) In autoxidized oil, an oxidative reaction occured at 150°C200°C. This reaction could be detected more clearly during heating on TG and DSC curves with the progress of deterioration. In thermally oxidized oil, this reaction was not detected, but pyrolysis after weight started to decrease occured more quickly than that of the unoxidized oil, In the deteriorated oil, the temperature at which weight first started to decrease shifted to a lower region as deterioration proceeded. 2) The characteristics found on TG and DSC curves were confirmed to be due to peroxidative products in the autoxidized oil lipid components having carbonyl groups thermally oxidized oil and polar lipids containing free fatty acids, mono-and di-glycerides in deteriorated oil may be useful for determining the conditions for oil deterioration. 3) For autoxidized oil, the difference between the temperatures for initial and 25% weight reduction was closely correlated to peroxide, carbonyl value(COV)and p-anisidine values (AnV). For thermally oxidized oil, the decomposition rate between 250°C and 300°C was correlated to COV in the region below 30 and AnV in the region below 120. For deteriorated oil, the initial temperature of pyrolysis was correlated to COV, AnV, and polar lipid content.
N, N-dimethyl(long-chain alkylamines)are one of the most important fatty chemicals, far example, as the industrial intermediates which are derived to many commercial products such as the quarternary ammonium salts, amine oxide and so forth. These N, N-dimethyl (long-chain alkylamines)have been synthesized from the corresponding alcohols economically over many kinds of heterogeneous catalysts. But these catalysts are not satisfactory enough both in activity and selectivity. The mechanism of the amination of alcohols has been investigated for a long time, and required the dehydrogenation and hydrogenolysis abilities of the catalysts used in this reaction. We, in this work, planned to use copper as the catalyst for dehydrogenation and nickel as that far hydrogenolysis, and found Cu-Ni catalyst supported on SiO2/Al2O3 gave very high activity and selectivity in the amination of dodecyl alcohol. When the weight ratio of Cu/Ni was 4/1, it gave the maximum of activity and selectivity. The valence states of surface metals of the catalyst were analyzed by using ESCA. Copper was reduced to Cu0 or Cu+ in the hydrogen atmosphere at 200°C. Nickel was not reduced in the same atmosphere. When there was much amount of Ni2+ on the catalyst surface, the selectivity for the amination reaction was low, Ni2+ was seemed to accelerate the disproportionation of dimethylamine (DMA).
The adsorption of sodium alkyl sulfates (sodium decyl, sodium dodecyl, sodium tetradecyl and sodium hexadecyl sulfates) on nylon particles from their aqueous solutions was investigated by the electrokinetic method. The equilibrium adsorption isotherms of the surfactants were obtained from the electrokinetic potentials of particles dispersed in aqueous solutions of sodium alkylsulfates at different temperatures. The equilibrium constant of adsorption, K, and the saturated adsorption amount, Γs, were determined from Langmuir plots. The values of K and Γs by the electrokinetic method were compared with those obtained by the electric conductivity method under the same experimental conditions, The values of K and thermodynamic parameters determined by the electrokinetic and electric conductivity methods agreed with each other. The values of Γs obtained by the former method, however, were from 1/40 to 1/50 those calculated by the latter. Comparison of Γs by the both methods provided information on the slipping plane and the dissociation degree of the adsorbed surfactants.
The effects of salting-out on the adsorption properties of humic substances was investigated using activated carbon fiber made from phenol resin (ACF) and electronic conduct i v e carbon black (EC). By salting-out, the amounts of humic acid (higher molecular-weight components) in humic sbstances dissolved in water decreased, while those of fulvo acid (lower molelcular-weight components) remained the same. ACF with many micropores were found to serve well as an adsorbent for removing humic substances dissolved in water after the treatment of salting-out.
A study was made of the solubilities of NaSCN, Na2CO3, Na2SO4, and urea in mixed solutions of sodium dodecyl-tri(oxyethylene)sulfate (DES) and sodium tetradecenesulfonate (AOS) at a concentration of 20wt %/ Solubility was measured at 25°C by a visual method. A maximum on the solubility vs. mole fraction curve was found at a molar ratio of AOS (1) : DES (2) for Na2CO3 and AOS (1) : DES(1) for NaSCN, but was not observed for Na2SO4 or urea. The maximum solubilities of Na2CO3, and NaSCN corresponded about 87 % and 30 %, respectively, those when using pure water at the solvent at 25°C maximum. Na2CO3 solubility was also observed in mixed surfactnt solutions of DES with other kinds of surfactants. Thus, maximum solubility may be considered to take place when (1) at leass alkylpoly(oxyethyylene)sulfate bil is present at the surfactant in solution, and (2) the hydration of salt dissolved is weaker than that of ionic polar groups (R-SO3- or R-SO4-), but stronger than that of poly(oxyethylene) groups in the surfactant.
A simple and reliable method to qualify and quantify autoxidized triglycerides simultaneously was developed using reversed phase HPLC equipped with an RI detector. When certain triglycerides such as olive, safflower and linseed oil were subjected to HPLC analysis, only one peak for unoxidized and four peaks for autoxidized triglycerides appeared on the chromatogram under the conditions used with hexane :methanol : 2-propanol (98:1:1) as the eluent. The four peaks of each autoxidized triglyceride, on the chromatogram were assigned as unoxidized triglycerides, di-, mono- and tri-hydroperoxides of triglycerides, respectively. For the POV determination, the calibration curve was made from the linear relationship between the ratio of total peak area of hydroperoxides to that of all peaks on the chromatogram and POV of the sample triglyceride in the range of 301000 meq/kg. The POV thus determined was quite close to that measured by potentiometric titration.
To study the surface adsorption of cationic surfactants on hydrophilic polymer latices, the ζ-potentials of styrene/acrylic acid [P(St/AA)] copolymer latices were measured in aqueous alkyl pyridinium bromide solutions (abbr. APB, CnH2n+1 NC5H5Br ; n=12 : DPB, n=14 : TPB, n=16 : HPB) and compared with those of polystyrene (PS), styrene/2-hydroxyethyl methacrylate copolymer [P(St/HEMA)] and styrene/acrylamide copolymer [P St/AAm] latices. Surface charge density (σ) was proportional to the amount of acrylic acid (AA) used in the copolymeation. σ for P(St/AA) latices increased with pH. The distance t from the Stern layer riz to slipping plane in the electrical double layer increased with the AA fraction. Hydrous poly acrylic acid (PAA)layers thus appear to be present on the surfaces of P(St/AA)latices. PAA layer thickness is less than that of poly-HEMA or poly-AAm layers. The amount of surfactant adsorbed per unit area of a latex was calculated from the ζ-potential value. The sign of the ζ-potential of a latex changed from negative to positive with increase in surfactant concentration. Surf actant adsorption increased with APB hydrocarbon chain length in the order, HPB>TPB>DPB. These results can be explained by elctrostatic attractive force and hydrophobic interaction. The amount of surfactant adsorbed on P(St/AA) latices was less than an the PS latex, equal to that on P(St/HEMA) and P St/AAm5 latices and larger than that on the P(St/AAm10) latex. The negative value of free energy of adsorption ΔG for a surfactant on a latex decreased with PS>P(St/HEMA)-P(St/AAm5)-P(St/AA5)>P(St/AAm10). The large posltlve value of enttopy of adsorption ΔS indicates the importance of entropic interactions and the formation of hydrophobic bonds as the driving force for adsorption of a surfactant on a latex surface. Steric prevention by a PAA layer may be less than that by poly-HEMA and poly-AAm layers.
Far 25 brands of margarines obtained commercially in Malaysia, Singapore and Thailand, general properties were investigated, particularly in regard to tocopherol, tocotrienal, sterol and fatty acid composition, compared to that of palm oil. The samples were 8 brands of domestic margarines including 3 unsaturated (PU) from Malaysia, 9 imported margarines and an imported (Australia 6 including 5 PU, Norway 3) and 2 domestic compound butters from Singapore (Australia: PU) and 4 domestic margarines and a domestic sweet spread from Thailand. Three brands of domestic salad oil (Malaysia 1, Singapore 2) obtained at same time were studied in the same manner. 1) As general components, these margarines generally contained more salt and less milk than those manufactured in Japan. In particular, the 2 domestic samples from Thailand contained no milk. The melting points of the oils separated from the 2 domestic margarines of Thailand and one (PU) of Malaysia were higher than the body temperature. The iodine and saponification values of the separated oils indicated lauric oil such as coconut oil to possibly be blended in all the margarines except PU, and the sweet spread. 2) The analysis of tocopherol, tocotrienol, sterol and fatty acid content indicated the following results. Palm oil is blended in all the margarines except the imparted and/or PU, and the salad oil. The oil is the main component of the salad oil of Malaysia. Coconut oil is blended in the domestic margarine but not in 2 PU of Malaysia or 2 of Thailand, the 2 imported margarine (Norway), and the sweet spread. Animal fat though not milk fat is present in 2 domestic (Malaysia 1, Thailand 1) and 3 imported margarines (Australia 1, Norway 2) and 2 PU margarines of Malaysia are manufactured from almost l00 % sunflower oil. 3) Based on the trans-unsaturated fatty acid composition, the proportion of hydrogenated oil blended in the margarines appears to became less with increase in the amount of tropical fat such as palm and coconut oil.