Alcohol Alkoxylate Research Articles

Surface Properties of an Alcohol Alkoxylate in the Presence of a Cationic Surfactant

AbstractAlcohol alkoxylate was prepared via propoxylation of an industrial alcohol ethoxylate. The chemical structure of the prepared compound was confirmed using FT‐IR and the physical properties were evaluated by the usual methods according to ASTM. The surface properties of the aqueous solution of alcohol alkoxylate were determined with or without addition of a cationic surfactant in comparison to the corresponding alcohol ethoxylate. The measured parameters were surface tension, CMC, maximum surface excess, minimum surface area and the interaction parameter (β). These data indicate that surface properties changed due to the attractive complex formation in the mixed system.

Efficiency of Laundry Polymers Containing Liquid Detergents for Hard Surface Cleaning

AbstractThree water soluble laundry polymers were employed for the first time in liquid detergent formulations for hard surface cleaning. The polymers included in the formulations were the sodium salt of maleic acid/olefin copolymer (P1, anionic), polyethyleneimine (P2, cationic), and polyethylene glycol‐g‐vinyl acetate (P3, nonionic). Commercially available surfactants (C10 Guerbet alcohol alkoxylate (FAEO), caprylyl/decyl glucoside (APG), and the sodium salt of ethoxylated alkyl ether sulfate (SLES) were chosen to formulate bathroom, kitchen, and all‐purpose cleaners, which provide the desired broad of pH range for hard surface applications. Their hard surface cleaning efficiencies were also compared with an amphoteric polymer (amino modified polycarboxylate, P4) as amphoteric polymers are the most suitable structures for hard surface cleaning. The standard test method and the cleaning device, the so‐called cleaning robot, were used to investigate the primary cleaning performances and synergies of the chosen polymers in a hard surface cleaners system. Secondary cleaning performance tests, which indicate the effects of the hard surface cleaners on surface modification, were also performed. The results revealed that the formulations containing P3 and P4 gave the better cleaning performance for primary cleaning tests whereas only P4‐containing formulations showed the significant results for secondary cleaning tests.

Improving the Uniformity of Emitter Air Bubble Delivery during Oxygation

AbstractDrip irrigation may be used to deliver water and air to plant root systems, although uniformity of air bubble delivery along the irrigation line is an issue. Use of 1.2 ppm of a nonionic surfactant (alcohol alkoxylate) in an open-end drip irrigation system increased the Christiansen uniformity coefficient (CUC) of the emitter air flow rates to 80%, compared to 20% without surfactant. In a closed-end irrigation system, addition of 32 ppm surfactant raised the CUC of the emitter air flow rates from 1 to 23% for the symmetric connectors and from −83 to 37% for the asymmetric connectors, respectively, over the controls without surfactant. In the absence of the surfactant, insertion of turbulence-inducing sealing plugs before the 9.5-mm-long symmetric and asymmetric connectors raised the CUC of the emitter air flow rates from 1 to 18% for the symmetric and from −82 to −64% for the asymmetric connectors, respectively. Regardless of the type of the connectors, the highest CUC for emitter air flow rates i...

Characterization and stability of solid dispersions based on PEG/polymer blends

Solid dispersions were prepared by a melting method from the water-insoluble model drugs carbamazepine and nifedipine and polyethylene glycol 1500 (PEG 1500) or 1:1 mixtures of PEG 1500 and the polymers polyvinylpyrrolidone (PVP 30, PVP 12), polyvinylpyrrolidone-co-vinylacetate (PVPVA) and Eudragit EPO (Eudragit) in order to combine advantages of the different carrier polymers (recrystallization inhibition, processability and stability). The solid dispersions were characterized by dissolution, powder X-ray diffractometry and microscopy directly after preparation and after storage for 3 and 6 months at 25 °C/0% relative humidity (RH) or 3 months at 40 °C/75% RH. More than 80% drugs were released from all solid dispersions within 20 min. The dissolution rate of carbamazepine decreased in the order of PEG 1500 > PEG 1500/Eudragit > PEG 1500/PVP 30 > PEG 1500/PVPVA > PEG 1500/PVP 12. The dissolution rank order was not directly correlated to the amorphous/crystalline state of the drugs, but rather to the properties of the PEG 1500/polymer compositions. Nifedipine was released in the order of PEG 1500 > PEG 1500/PVPVA > PEG 1500/PVP 30 > PEG 1500/PVP 12 > PEG 1500/Eudragit. Amorphous nifedipine was present in all PEG 1500/polymer dispersions except in pure PEG 1500 solid dispersion. The significant increase in dissolution rate of PEG 1500 solid dispersions was due to the reduced crystallinity of the drug and the excellent solubilisation properties of PEG 1500. After 6 months storage at 25 °C/0% RH, the solid dispersions released both drugs in the order PEG 1500/PVPVA > PEG 1500/PVP 30 > PEG 1500/PVP 12 > PEG 1500/Eudragit > PEG 1500. The stabilized amorphous state of the drug resulted in stable dissolution profiles of PEG 1500/PVPVA, PEG 1500/PVP 30 and PEG 1500/PVP 12 when compared to the PEG 1500 solid dispersions, which contained a higher amount of crystalline drug. The solid dispersions with PEG 1500/PVPVA or PEG 1500/PVP stored for 3 months at 40 °C/75% RH showed phase separation due to the hygroscopic properties of the polymers. The influence of 10% (w/w) of the solubilisers polyoxyl 40 hydrogenated castor oil (Cremophor), macrogol-15-hydroxystearate (Solutol) and fatty alcohol alkoxylate (Pluronic) on the dissolution rate and the physical state of the drug was significant.

Combination of chemical and electron-impact ionisation with GC×GC–qMS for characterization of fatty alcohol alkoxylate polymers in the low-molecular-weight range up to 700 Da

The class of fatty alcohol alkoxylates describes surfactants that are synthesised by reaction of fatty alcohols with alkoxides such as ethylene oxide or propylene oxide or a combination of both as copolymers. Such alkoxylates are used, for example, as nonionic surfactants in home and industrial cleaning and washing agents. Chemical characteristics of such alkoxylate copolymers, for example the degree of alkoxylation, the arrangement of building blocks (random or block polymerisation), the type of the starter, and endcapping, play an important role in application behaviour. The analysis of these characteristics is challenging because in many cases such copolymers have high polydispersity and a large number of constitutional isomers depending on the degree of alkoxylation. Furthermore, the alkoxylates often occur in a complex multicomponent matrix. Here we present a method for characterization of silylated fatty alcohol alkoxylates in the low-molecular-weight range by means of comprehensive two-dimensional gas chromatography-mass spectrometry with electron impact and chemical ionisation. This method also enables detailed analysis of the alkoxylates in a complex matrix such as modern detergents.

The Chronic Toxicity of Alcohol Alkoxylate Surfactants on Anaerobic Granular Sludge in the Pulp and Paper Industry

The chronic toxicity of an alcohol alkoxylate surfactant used in the pulp and paper industry was observed in methanogenic consortia under unfed conditions. Methanogenic inhibition was not observed until 250 h of famine conditions while in the presence of the surfactant. The delayed onset of inhibition is likely due to the amount of time necessary for the surfactant to partition into the cellular membrane which uncouples cellular energy conservation mechanisms and exhausts internal energy reserves necessary to maintain homeostasis.

Efficacy of alcohol alkoxylate surfactants differing in the molecular structure of the hydrophilic portion to control Phytophthora nicotianae in tomato substrate culture

Phytophthora nicotianae is a common and destructive pathogen of numerous ornamental, agronomic and horticultural crops such as tomato, tobacco and citrus. Three monobranched C 13 alcohol alkoxylate non-ionic surfactants were evaluated for in vitro inhibitory activity against the different asexual structures of P. nicotianae. The same surfactants, labelled MBA1301, MBA1303 and MBA1306, were tested for their in vivo control capacity against P. nicotianae root rot of tomato ( Lycopersicon esculentum) under glasshouse conditions. MBA1301, MBA1303 and MBA1306 differ in the molecular structure of the hydrophilic portion. The molecular weight of MBA1301 is comparable to that of MBA1303 and is eight times lower than that of MBA1306. The main in vitro activity for MBA1301 and MBA1303 was a direct lytic effect on the zoospores. Zoospore lysis was already observed in the presence of 1 μg ml −1 of these two surfactants and almost no zoospores survived an addition of 5 μg ml −1 surfactant. In addition, MBA1301 and MBA1303 reduced sporangia formation at a concentration of 5 μg ml −1. Both surfactants only affect mycelium growth at concentrations as high as 100 μg ml −1. MBA1306 did not show any effect on sporangia formation, zoospore release and mycelium growth of P. nicotianae at a concentration 10 times that of the other two surfactants. A good in vivo control of P. nicotianae on tomato in substrate culture was obtained for MBA1301 and MBA1303 whereas the control capacity of MBA1306 was significantly lower. The results of this research indicate that non-ionic alcohol alkoxylate surfactants can be used to control tomato root rot caused by P. nicotianae in substrate culture. In addition, the size rather than the arrangement of the polymers in the hydrophilic portion of the surfactant molecule determines the efficacy to control tomato root rot caused by P. nicotianae in substrate culture.

Control of brown root rot caused by Phytophthora cryptogea in the hydroponic forcing of witloof chicory ( Cichorium intybus var. foliosum) by means of a nonionic surfactant

The surfactant Atplus MBA1301, a monobranched C13 alcohol alkoxylate, was tested for its efficacy to control brown root rot, caused by the zoosporic pathogen Phytophthora cryptogea in the hydroponic crop production (forcing) of witloof chicory. In in vitro experiments, 4 μg ml −1 Atplus MBA1301 inhibited sporangia development, while motile zoospores of P. cryptogea ceased motility and lysed within 1 min upon exposure to 10 μg ml −1 surfactant. When the pathogen was artificially introduced in pot assays or in a mini hydroponic system using a mycelial suspension and/or zoospores as an inoculum, a concentration of 10 μg Atplus MBA1301 ml −1 nutrient solution was sufficient to obtain a good control. Root hair development appeared to be negatively correlated with disease incidence and disease severity and can be used to monitor the brown root rot disease in a nondestructive way. The surfactant Atplus MBA1301 was also tested in a commercial setting under growers’ conditions. Organically grown witloof chicory roots of the cultivar Vintor were artificially infected with 10 2 zoospores ml −1. A disease incidence of 90.8% was recorded in the infected control. Only 1.3% of the roots showed symptoms in a treatment with 10 μg ml −1 Atplus MBA1301. This is not significantly different from the healthy control, which remained free of symptoms. It can be concluded that Atplus MBA1301 has excellent potential to control Phytophthora brown root rot in witloof chicory hydroponic forcing.

Anaerobic Degradability of Alcohol Ethoxylates and Related Non-Ionic Surfactants

The anaerobic degradability of alcohol ethoxylates with various degrees of branching and several related substances was studied. Different inocula were employed in order to increase the probability of obtaining capable bacteria, and the degradation assays were fed with several small doses of the test substances in order to avoid inhibition by too high initial concentrations. Mineralization was quantified by monitoring the biogas production and inorganic carbon concentration in the liquid phase. Almost complete mineralization was achieved in the assays with linear alcohol ethoxylate, poly(ethylene glycol), dodecanol, 2-ethyl-hexanoic acid and 3-methyl-valeric acid. No significant degradation was detected in the assays with highly branched alcohol ethoxylate, 2-butyl-branched alcohol ethoxylate, alcohol alkoxylate, poly(propylene glycol) and iso-tridecanol. A 2-ethyl-branched alcohol ethoxylate was transformed to (2-ethyl-hexyloxy)-acetate, which was not further degraded. Apparently already the first step of anaerobic degradation of alcohol ethoxylates, the ethoxylate chain shortening, is sterically hindered by the alkyl branching. Alkyl branching in alcohol ethoxylates and the inclusion of propylene oxide units in alcohol alkoxylates seem to have a clearly more detrimental effect on anaerobic degradability than on aerobic degradability.

The acute toxicity of agricultural surfactants to the tadpoles of four Australian and two exotic frogs

Nonionic surfactants are frequently incorporated into pesticide formulations, and are therefore a group of chemicals to which amphibians may be exposed in agricultural or urban landscapes. However, little is known about the effects of surfactant exposure in amphibians. Feeding stage tadpoles of Bufo marinus, Xenopus laevis and four species of Australian frogs ( Crinia insignifera, Heleioporus eyrei, Limnodynastes dorsalis and Litoria moorei) were exposed to nonylphenol ethoxylate (NPE) and alcohol alkoxylate in static-renewal acute toxicity tests. All species exhibited nonspecific narcosis following exposure to both these surfactants. The 48-h EC50 values for NPE ranged between 1.1 mg/l (mild narcosis) and 12.1 mg/l (full narcosis). The 48-h EC50 values for alcohol alkoxylate ranged between 5.3 mg/l (mild narcosis) and 25.4 mg/l (full narcosis). Replicate acute toxicity tests with B. marinus exposed to NPE at 30°C over 96 h indicated that the narcotic effects were not particularly time dependant. The mean 24, 48, 72, and 96-h EC50 (mild narcosis) values were 3.6, 3.7, 3.5 and 3.5 mg/l, respectively. The mean 24, 48, 72 and 96-h EC50 (full narcosis) were 4.0, 4.1, 4.2 and 4.0, respectively. Acute toxicity tests with B. marinus exposed to NPE at 30°C under conditions of low dissolved oxygen (0.8–2.3 mg/l) produced a two to threefold increase in toxicity.

Effects of branching upon some surfactant properties of sulfated alcohols

AbstractA study was undertaken to determine the surfactant properties of various sulfated alcohols. Most notably, the Krafft point and the ability to emulsify decane were studied. A series of sulfated Guerbet alcohol and Guerbet alcohol alkoxylate sulfates with 16 carbon atoms and an analogous series based upon cetyl alcohol, a linear C16, were studied as hydrophobes.