Katarzyna Materna

Herbicidal Ionic Liquids with 2,4-D

Abstract Three herbicidal ionic liquids (HILs)—alkyldi(2-hydroxyethyl)methylammonium (2,4-dichlorophenoxy)acetate, dialkyldimethylammonium (2,4-dichlorophenoxy)acetate, and alkyltrimethylammonium (2,4-dichlorophenoxy)acetate—were synthesized and their activity against broad-leaved weeds was investigated under field conditions. HILs as [cation][2,4-D] used in winter wheat were much more active compared to 2,4-D-dimethylammonium salt and demonstrated efficacy similar to 2,4-D 2-ethylhexyl ester. HILs exhibited desirable surface properties such as low contact angle of droplets and low surface tension. Moreover, the HILs may be safer to operators and neighboring plants due to their nonvolatile nature. HILs at 450 g ha−1 of 2,4-D did not injure wheat. Nomenclature: Alkyldi(2-hydroxyethyl)methylammonium (2,4-dichlorophenoxy)acetate; dialkyldimethylammonium (2,4-dichlorophenoxy)acetate; alkyltrimethylammonium (2,4-dichlorophenoxy)acetate.

Long-Alkyl-Chain Quaternary Ammonium Lactate Based Ionic Liquids

A new group of quaternary ammonium lactate based ionic liquids have been prepared and characterized. Didecyldimethylammonium (DDA) and benzalkonium (BA) D,L- and L-lactates are air-stable, hydrophilic, surface-active salts. They are very effective antibacterial and antifungal agents, especially the DDA lactates, against Streptococcus mutants and Candida albicans. Their activities are comparable or more effective than the original benzalkonium chloride. In addition, they have been shown to be good insect-feeding deterrents. However, they are poor antifungal agents for wood preservation. The toxicity of the DDA and BA lactates has also been studied and the results are presented in this paper.

Recovery of various phenols and phenylamines by micellar enhanced ultrafiltration and cloud point separation

The recovery of organic pollutants by micellar enhanced ultrafiltration and cloud point technique was studied. It was found that micellar enhanced ultrafiltration and cloud point technique enable high recovery of some organic pollutants without using any hydrocarbon solvents. The cloud point technique gives higher recovery than ultrafiltration. Appropriate surfactants having low critical micelle concentration and low cloud point must be used. Oxyethylated fatty acid methyl esters are the most appropriate for cloud point separation as, having ester groups, they are quickly hydrolyzed in sewage systems. CTAB and SDS are appropriate for ultrafiltration. The recovery of pollutants in both considered techniques can be estimated from the micelle binding constants or from linear solvation free energy relationships according to the Abraham model. The efficiency of separation increases with an increase of pollutant hydrophobicity and excess molar refraction. Hydrogen bond acidity of pollutants improves separation from systems containing nonionic surfactants and CTAB but it does not affect separation in the presence of SDS. Hydrogen bond basicity and dipolarity of pollutants decrease the recovery. The derived models enable the selection of pollutants which can be efficiently removed from aqueous streams by the cloud point technique and micellar enhanced ultrafiltration.

Synthesis, properties and evaluation of biological activity of herbicidal ionic liquids with 4-(4-chloro-2-methylphenoxy)butanoate anion

In this study, fourteen new herbicidal ionic liquids (HILs) based on MCPB with a 1-alkyl-1-methylpiperidinium cation were synthesized and characterized. The effect of the alkyl chain length on the physicochemical properties of HILs was determined. Additionally, thermal analysis, solubility in 10 representative solvents, and surface and herbicidal activity were determined. The herbicidal efficacy was tested in greenhouse experiments by using common lambsquarters (Chenopodium album L.) and oilseed rape (Brassica napus L.) as test plants. The ionic liquids were more effective than the commercial herbicide. Moreover, there was a relationship between the surface activity of HILs and herbicidal efficiency.

Solvothermal synthesis of hydrophobic chitin–polyhedral oligomeric silsesquioxane (POSS) nanocomposites

Chitinous scaffolds isolated from the skeleton of marine sponge Aplysina cauliformis were used as a template for the deposition of polyhedral oligomeric silsesquioxanes (POSS). These chitin-POSS based composites with hydrophobic properties were prepared for the first time using solvothermal synthesis (pH 3, temp 80 °C), and were thoroughly characterized. The resulting material was studied using scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and thermogravimetry. A mechanism for the chitin-POSS interaction after exposure to these solvothermal conditions is proposed and discussed.

Sweet ionic liquids-cyclamates: Synthesis, properties, and application as feeding deterrents

In this paper, we show that sweet quaternary ammonium, pyridinium, and imidazolium cyclamates are cheap, thermally stable, surface and biologically active ionic liquids, with potential application as feeding deterrents.

Multifunctional long-alkyl-chain quaternary ammonium azolate based ionic liquids

A new group of quaternary ammonium ionic liquids with azolate (benzotriazolate, 1,2,4-triazolate, 4-nitroimidazolate, 2-methyl-4-nitroimidazolate) anions was prepared and characterized. The synthetic method employed was easy and quick, and required a polar solvent. The obtained ionic liquids were tested as anti-microbial and anti-fungal plant protection agents. Additionally, the surface-active properties and the phytotoxicity of the quaternary ammonium azolates were also studied. These clearly defined ionic liquids were found to be very effective anti-bacterial and anti-fungal agents.

Cross-flow ultrafiltration of micellar solutions containing selected phenols

Cross-flow ultrafiltration of micellar solutions containing phenols (phenol, 4-methylphenol, 4-chlorophenol, 2,4-dichlorophenol and 4-methoxyphenol) was studied. Oxyethylated coconut fatty acid methyl esters of an average oxyethylation degree of 10 and hexadecyltrimethylammonium bromide were used as surfactants. It was found that the hydrophilic membranes made of cellulose and polyethersulfone were useful for repeated separation of phenols from micellar solutions containing oxyethylated fatty acid methyl esters and hexadecyltrimethylammonium bromide. The membranes could be used several times because of the reversible blocking with surfactants. The rejection of phenols could be modelled by the Abraham linear solvation energy relationship. The pollutant hydrophobicity and basicity were the most important parameters affecting the rejection. Mixed micelles containing non-ionic and cationic surfactants improved solubilization of phenols and their rejection in membrane ultrafiltration.

2-Ethylhexanol Derivatives as Nonionic Surfactants: Synthesis and Properties

Abstract The synthesis and basic properties of 2-ethylhexanol based innovative nonionic surfactants are described in this paper. 2-Ethylhexanol as an available and relatively inexpensive raw material was used as the hydrophobe source modified by propoxylation and followed by polyethoxylation. As the result, six series of 2-ethylhexyl alcohol polyalkoxylates (EHPmEn) were obtained with three steps of propoxylation, each followed by polyethoxylation and two series only with polyethoxylation (EHEn). Two different catalysts were used, a dimetalcyanide and KOH. Values of average conversion rates and chemical content of the obtained products (GC, TG and GPC techniques) were compared. The influence of the applied catalyst and polyaddition degree on the homologue distribution, reactant conversion and amount of byproducts is discussed. The basic physicochemical parameters including refractive index, solubility in polar media, foaming properties and wettability were investigated and compared. Furthermore, surface activity parameters, i.e. surface tension (γCMC) and critical micelle concentrations were determined. Results are compared to C12–14 alcohol ethoxylates (LaEn). Accordingly, it was found that the studied 2-ethylhexyl alcohol based compounds are effective, low foaming nonionic surfactants.

Pyrrolidinium herbicidal ionic liquids

In this work, sixteen new pyrrolidinium herbicidal ionic liquids (HILs) with phenoxycarboxylate anions were synthesized and characterized. The effect of the alkyl or alkoxymethyl chain length and type of anion on the physicochemical properties, such as density, viscosity and refractive index of HILs, as well as on the thermal stability and surface activity, were determined. The oxygen presence in the structures of the prepared HILs significantly affects their thermal and surface properties. Furthermore, the herbicidal efficacy was tested in greenhouse experiments by using common lambsquarters (Chenopodium album L.) as a test plant. The novel pyrrolidinium ionic liquids were more effective than the commercial herbicides.