The influence of cation and anion structure of new quaternary ammonium salts on adsorption and leaching

Holzforschung ◽  
2005 ◽  
Vol 59 (2) ◽  
pp. 190-198 ◽  
Author(s):  
Jadwiga Zabielska-Matejuk

Abstract This study examined the effect of cation and anion chemical structure of new quaternary ammonium and imidazolium compounds (QAC, bis-QAC, IC, bis-IC) on the adsorption onto Scots pine wood (Pinus sylvestris L.) and resistance to water leaching. The group of copper (II) modified QACs, containing copper-chloro-acetate complexes in the anion structure, was also examined. The length of alkyl hydrophobic substituents in the cation structure significantly influences adsorption. The adsorption characteristics were statistically related to the alkyl chain length of new quaternary ammonium salts (quantitative correlations between CMC and adsorption values). Bis-ICs adsorb onto Scots pine wood with the greatest difficulty and the slowest and are also leached to the greatest degree. A varied adsorption of chloride ion cations and a several times higher leaching of chlorides than cations of the examined salts from the saturated wood were observed. The anion modification of bis-QAC and bis-IC of copper-chloro-acetate complexes causes decreased adsorption and resistance to the leaching of these salts. As a result of the performed regression analysis of Langmuir and Freundlich adsorption isotherms, it was found that the adsorption of the examined compounds onto wood was governed by both chemical and physical processes. New quaternary ammonium and imidazolium compounds represent potential wood preservatives.

2012 ◽  
Vol 727-728 ◽  
pp. 1552-1556
Author(s):  
Renata Barbosa ◽  
Dayanne Diniz Souza ◽  
Edcleide Maria Araújo ◽  
Tomás Jefférson Alves de Mélo

Studies of degradation have verified that the decomposition of some quaternary ammonium salts can begin to be significant at the temperature of about 180 ° C and like most thermoplastics are processed at least around this temperature, the thermal stability of the salt in clay should always be considered. Some salts are more stable than others, being necessary to study the degradation mechanisms of each case. In this work, four quaternary ammonium salts were characterized by differential scanning calorimetry (DSC) and thermogravimetry (TG). The results of DSC and TG showed that the salts based chloride (Cl-) anion begin to degrade at similar temperatures, while the salt based bromide (Br-) anion degrades at higher temperature. Subsequently, a quaternary ammonium salt was chosen to be used in organoclays, depending on its chemical structure and its thermal behavior.


Chirality ◽  
2008 ◽  
Vol 20 (10) ◽  
pp. 1085-1091 ◽  
Author(s):  
Ruxandra Gheorghe ◽  
Lise-Marie Chamoreau ◽  
Josef Kapitan ◽  
Nikolaï S. Ovanesyan ◽  
Sergei M. Aldoshin ◽  
...  

1979 ◽  
Vol 34 (5-6) ◽  
pp. 485-486 ◽  
Author(s):  
Ivan Lacko ◽  
Ferdinand Devínsky ◽  
Ľudovít Krasnec ◽  
Dušan Mlynarčik

Abstract N,N-Dialkyl Ammonium Salts of Saturated Heterocyclic Amines, Antimicrobial Activity Antimicrobial activity of N-alkyl-N-dodecylpiperidinium bromides and N-ethyl-N-dodecylheterocycloalkyl ammonium bromides (pyrrolidine, morpholine, perhydroazepine) deter­ mined on grampositive and gramnegative bacteria, yeasts and moulds, presented as minimum inhibition concentration (MIC). Comparison of the effect of change of structure: lenghtening of alkyl chain, change of heterocyclic ring. Change in the lenght of alkyl chain markedly affects the antimicrobial activity, change of heterocyclic ring has no substantial effect. The most active compounds were N-heptyl-and N-hexyl-N-dodecylpiperidinium bromides.


2012 ◽  
Vol 31 (6_suppl) ◽  
pp. 296S-341S ◽  
Author(s):  
Lillian C. Becker ◽  
Wilma F. Bergfeld ◽  
Donald V. Belsito ◽  
Ronald A. Hill ◽  
Curtis D. Klaassen ◽  
...  

Quaternary ammonium salts, including alkyl chain, alkanol, and polymer derivatives (trimoniums) are used in cosmetics mainly as surfactant-cleansing agents, hair-conditioning agents, and antistatic agents.  The Cosmetic Ingredient Review Expert Panel reviewed the relevant animal and human data and noted gaps in the available safety data for some of the trimomiums.  The available data on many of the trimoniums are sufficient, however, and similar structural activity relationships, functions in cosmetics, and cosmetic product usage supported extending these data to the entire group.  These ingredients were determined to be safe in the present practices of use and concentration when formulated to be nonirritating.


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