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991.
M. J. Danzig J. L. O'Donnell E. W. Bell J. C. Cowan H. M. Teeter 《Journal of the American Oil Chemists' Society》1957,34(3):136-138
Summary Soybean fatty acids were conjugated with alkali, and the contained, conjugated dienoic acids were isomerized with iodine to
thetrans,trans configuration. Adducts were prepared from thesetrans,trans-conjugated acids by condensation with maleic anhydride and acrylic acid. The adducts were isolated, purified, and converted
to esters by using a variety of alcohols, including methyl, ethyl,n-propyl,n-butyl, and allyl alcohols. Esters made from saturated alcohols were converted into the corresponding epoxy derivatives.
All of the esters (except allyl) and all of the epoxy esters were compatible with an equal weight of polyvinyl chloride and
appeared to be primary plasticizers for this plastic. The epoxy esters were effective in inhibiting heat deterioration of
polyvinyl chloride.
Presented at fall meeting. American Oil Chemists' Society, September 23–26, 1956, Chicago, Ill. 相似文献
992.
993.
J. B. Stelzer A. Feldhoff J. Caro M. Fait D. Habel E. Feike H. Schubert 《化学,工程师,技术》2004,76(8):1086-1092
994.
To impart easy‐care properties to cellulose‐containing fabrics along with avoiding any harmful effects of formaldehyde on both the health and the environment, attempts have been made to use citric acid (CA) as an ester crosslinking agent along with different catalytic systems in the absence and presence of certain additives. Further, fixation conditions, type of crosslinking agent, as well as type of substrate have been studied. Results revealed that the enhancement in carboxyl content, performance properties, and the decrease in tear strength (TS) as well as in whiteness indices (WI) of the finished fabric samples were increased by increasing CA concentration up to 80 g/L and by raising thermofixation temperature from 140 up to 180°C for 90 s. Inclusion of triethanolamine hydrochloride (TEA. HCl), decreased the carboxyl content, TS, color strength K/S, as well as oily stain release rating (SRR) of the finished fabric samples along with an increase in bound nitrogen (%N), wrinkle recovery angle WRA, and an improvement in WI without affecting the durable press rating (DP). Within the range examined (0–30 g/L), increasing PEG‐600 concentration improved the wet resiliency, TS, as well as WI properties of the finished samples. Increasing DMDHEU ratio in the CA/DMDHEU crosslinking system gave rise to an increase in %N, WRA (dry and wet), DP, as well as in free CH2O of finished fabrics, along with a slight improvement in WI values. On the other hand, the TS, carboxyl content, K/S, SRR values of the finished fabric samples were lower at a higher DMDHEU ratio. Increase in carboxyl content, %N, WRA (dry and wet), DP and SRR, as well as extent of post dyeing (K/S) of the treated fabric samples upon using different ester crosslinking agents followed the descending order: citric acid > pyromellitic dianhydride. The opposite holds true for the TS, and WI values. Among the esterifying catalysts used, and for a given set of finishing conditions, NaH2PO2 · H2O proved to be the most effective one, and the following order of effectiveness may be drawn: NaH2PO2 · H2O > K2HPO4 > Na3–citrate > Na2–tartrate. Inclusion of silicone softener in the finishing formulation brought about an improvement in softeness degree, WRA, %N, DP, TS as well as K/S values along with a decrease in carboxyl content, SRR, and WI values of the treated fabric samples, regardless of the used silicone softener.The performance properties of the finished fabric samples were determined by the type and nature of the substrate. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2243–2253, 2002 相似文献
995.
Summary Free radical copolymerization of acrylonitrile (AN, M1) with poly(2,6-dimethyl-1,4-phenylene oxide)--vinylbenzyl ether (PPO-VBE, M2,
n + 4200g/mol,
w/
n + 1.04) was performed at 60°C in either a mixture of N,N-dimethylformamide/toluene or tetrahydrofuran, using 2,2-azoisobutyronitrile (AIBN) as initiator. The characterization of the resulting polyacrylonitrile grafted with poly(2,6-dimethyl-1,4-phenylene oxide) (PAN-g-PPO) was performed by 200 MHz 1H-NMR spectroscopy and solubility. 相似文献
996.
In order to obtain more detailed information on the mechanism of the polymerization of N-vinyl-carbazole (N-VC) in the presence of carbon black, a comparison of the rates of conversion under various conditions was made and the following results were obtained. The phenolic hydroxyl groups on the surface of carbon black were found to have an ability to initiate the polymerization, and an increase in dielectric constant of the solvent increased the rate of polymerization. Using the mixture of N-VC and comonomers such as styrene or methyl methacrylate, we found that styrene gives a copolymer with N-VC, while methyl methacrylate gives no copolymer during the early stage of polymerization. The phenomena observed here indicate that the nature of polymerization of N-VC initiated by carbon black is cationic. 相似文献
997.
Angelika Elsner G. Mieth W. Engst L. Aust H.-J. Leverenz 《European Journal of Lipid Science and Technology》1991,93(8):290-293
Sucrose carboxylic acid polyesters are in dependence of the degree of acylation and fatty acid composition more or less undigestible or emulsifying fat substitutes and functional additives for foods. In this connection the relationships between their molecular parameters and functional properties are discussed. New procedures of the solvent-free synthesis are presented. Furthermore, open biochemical and toxicological problems of pinocytosis and accumulation of intact polyesters in organs and tissue being still under investigations are considered. 相似文献
998.
Y. hen M. M. Abraham L. D. Bentsen D. P. H. Hasselman 《Journal of the American Ceramic Society》1982,65(7):c104-c105
The thermal diffusivity/conductivity of Ni-doped MgO single crystals was measured as a function of temperature by the laser-flash method. Nickel in the form of the substitutional solid solution, Ni2+ , has a much greater effect on the thermal diffusivity / conductivity than precipitated Ni colloids. These results are discussed in terms of phonon and photon scattering effects. 相似文献
999.
Cotton and cotton/polyester fabrics were treated against microbial attack by applying a formulation based essentially on ZnO under high‐energy radiation and thermal curing. To achieve the homogeneity and the reactivity of the treating formulation, a binder (Impron MTP) and a dispersing agent (Setamol WS) were used with ZnO. The antimicrobial property of the fabrics was evaluated, in terms of mechanical properties, by a soil burial test. Moreover, the effect of antimicrobial finishing on the dyeing properties in terms of color strength was investigated. It was found that the best composition that affords the best antimicrobial protection to cotton fabrics contains 2% ZnO, 2% binder, and 1% dispersing agents. For the cotton/polyester blend, the best results were achieved at the same conditions except the ZnO was 1%. It was found that the treatment under the effect of electron‐beam irradiation is better than that of gamma irradiation and thermal curing. The results showed that when the finishing process was carried out before dyeing with a reactive dye, it affects the color strength rather than performing the finishing after the dyeing process. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1129–1137, 2003 相似文献
1000.
Toughening by Monoclinic Zirconia 总被引:1,自引:0,他引:1
The toughening induced by monoclinic ZrO2 in the absence of microcracking was investigated, using ZnO as the host material. Toughness levels Kc in excess of the host toughness Kc M were achieved, attaining a peak toughness Kc /Kc M ∼1.7, at monoclinic ZrO2 volume concentrations 0.2. This toughening is attributed to crack/particle interactions, associated with the deflection and bowing of the crack by the residual strain field around the monoclinic ZrO2 particles. 相似文献