scholarly journals Phenolyses of 1-Adamantyl Chloride, Bromide, andp-Toluenesulfonate in Binary Mixtures of Phenol with Benzene. The Rates and the Product Distribution

1972 ◽  
Vol 45 (4) ◽  
pp. 1191-1198 ◽  
Author(s):  
Kunio Okamoto ◽  
Kôichi Matsubara ◽  
Tomomi Kinoshita
Keyword(s):  
Binary Mixtures ◽  
Product Distribution

Micellar Catalysis of Organic Reactions. XXXI. A Study of the Effects of Micelles of Cetyltrimethylammonium Bromide on Some SNAr Reactions in Aqueous Binary Mixtures

1991 ◽  
Vol 44 (5) ◽  
pp. 667 ◽  
Author(s):  
TJ Broxton
Keyword(s):  
Binary Mixtures ◽  
Cetyltrimethylammonium Bromide ◽  
Product Distribution ◽  
Reaction Centre ◽  
Alkyl Ether ◽  
Subsequent Reaction ◽  
Aryl Ethers ◽  
High Yields ◽  
Aqueous Binary Mixtures ◽  
Acidic Alcohol

The effect of micelles of cetyltrimethylammonium bromide ( ctab ) on the SNAr reactions of 1-fluoro-2,4-dinitrobenzene (1), 2-fluoro-5-nitrobenzoate (2) and 4-fluoro-3-nitrobenzoate (3) with sodium hydroxide in aqueous binary mixtures with several alcohols has been studied. Two products were detected in all of these reactions: the phenol from reaction with hydroxide ions, and an aryl alkyl ether from reaction with the alkoxide ions. Micelles of ctab increased the percentage yield of the ether product at the expense of the phenol for compounds (1) and (2) in most of the binary mixtures used. For compound (3), however, micelles of ctab had little effect on the product distribution. These differences were attributed to differences in the orientation of substrates (2) and (3) when solubilized by micelles of ctab . Very high yields of the ether were obtained for the reaction of compound (1) with hydroxide ions in trifluoroethanol /water mixtures, and this was attributed to the considerable ionization of trifluoroethanol which was the most acidic alcohol used in this work. The lowest yield of the ether product was obtained in reactions of compound (1) with hydroxide ions in propan-2-ol/water mixtures since propan-2-ol was the least acidic alcohol used. These results are compared with those previously reported for the reaction of compound (1) in the presence of hydroxy-functionalized micelles and β- cyclodextrin. In the presence of micelles of ctab the aryl alkyl ethers derived from compounds (1) and (2) underwent a subsequent SNAr reaction with hydroxide ions during which the alkoxide ion was displaced. For compound (3) no subsequent reaction of the ether was detected in the presence of micelles of ctab . This was also attributed to the orientation of this product within the micelle. The reaction centre was buried in the micellar interior, and hence was shielded from a subsequent reaction. The rates of this subsequent reaction for compound (1), and of the decomposition of micellar aryl ethers and of cyclodextrin aryl ethers derived from compound (1), are also compared. The increase in the yield of the ether product in the presence of micelles was attributed to the increased ionization of alcohols in the presence of cationic micelles.

Thermodynamic properties of binary mixtures containing thiaalkanes

1980 ◽  
Vol 77 ◽  
pp. 445-449 ◽  
Author(s):  
Zohra Ferhat-Hamida ◽  
Robert Philippe ◽  
Jean-Claude Merlin ◽  
V. Kehiaian
Keyword(s):  
Thermodynamic Properties ◽  
Binary Mixtures

Use of thermomechanical pulp fibers from waste woods for making eco-friendly cushioning material

TAPPI Journal ◽  
2010 ◽  
Vol 9 (7) ◽  
pp. 15-21 ◽  
Author(s):  
JI-YOUNG LEE ◽  
CHUL-HWAN KIM ◽  
JEONG-MIN SEO ◽  
HO-KYUNG CHUNG ◽  
KYUNG-KIL BACK ◽  
...  
Keyword(s):  
Impact Test ◽  
Product Distribution ◽  
Expanded Polystyrene ◽  
Thermomechanical Pulp ◽  
Fiber Structure ◽  
Pulp Fibers ◽  
Cationic Starch ◽  
Thermal Insulating ◽  
Surface Sizing ◽  
The Impact

Eco-friendly cushioning materials were made with thermomechanical pulps (TMPs) from waste woods collected from local mountains in Korea, using a suction-forming method without physical pressing. The TMP cushions had superior shock-absorbing performance, with lower elastic moduli than expanded polystyrene (EPS) or molded pulp. Even though the TMP cushions made using various suction times had many voids in their inner fiber structure, their apparent densities were a little higher than that of EPS and much lower than that of molded pulp. The addition of cationic starch contributed to an increase in the elastic modulus of the TMP cushions without increasing the apparent density, an effect which was different from that of surface sizing with starch. In the impact test, the TMP cushions showed a more ductile pattern than the brittle EPS. The porosity of the TMP cushion was a little less than that of EPS and much greater than that of molded pulp. The porous structure of the TMP cushions contributed to their excellent thermal insulating capacity, which was equivalent to that of EPS. In summary, the TMP packing cushions showed great potential for surviving external impacts during product distribution.

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