Peaked distribution ethoxylates-Their preparation,characterization and performance evaluation

A peaked ethylene oxide distribution alcohol ethoxylate can be produced using new catalyst systems. The mechanism of ethoxylation is discussed. Such Novel™ ethoxylates are markedly different from a conventional ethoxylate in physical properties and performance characteristics. Performance and formulation studies show several advantages for the peaked distribution in typical household product formulations. Presented at the AOCS meeting in Dallas, May 1984. Deceased.     

Compatibility of nonionic surfactants with membrane materials and their cleaning performance

Membranes applied in industrial processes, such as for the desalination of seawater as well as for dairy and beverage industry are subjected to fouling resulting in a decline of their performance. In order to regain the flux of the membranes, cleaning procedures are conducted, whereby inorganic scale is often removed with acids and organic matter with surfactants under alkaline conditions. Currently, either ionic surfactants or alkylphenol ethoxylates are utilised to clean membranes of organic matter. Other nonionic surfactants (i.e. fatty alcohol ethoxylates) are not applied, due to the assumption that they irreversibly adhere to the membrane surface and thereby clog the pores. At BASF we have studied the adsorption of a wide range of nonionic surfactants to membrane materials. It was shown, that the affinity of nonionic surfactants critically depends on their structure. Linear alkyl ethoxylates irreversibly adsorb to the membrane surfaces, whereas branched alkyl ethoxylates do not. In a second step, we tested the cleaning performance of nonionic surfactants. Similar to the results for adsorption, a structure-performance relationship was discovered where several branched alkyl ethoxylates showed excellent cleaning results. In a third step, combinations of nonionic surfactants, chelating agents and enzymes were tested in terms of cleaning efficiency. All tested combinations showed excellent cleaning performance on bacterial fouling layers.     

Sulfates of ethoxylated tridecyl alcohol in dishwashing formulations

Summary The foam stability of several light-duty liquid dishwashing formulations containing sulfated ethoxylates of tridecyl alcohol, lauryl alcohol, and nonylphenol have been compared. The effects of water hardness, sulfating agent, and ethylene oxide/hydrophobe mole ratio have been examined. In very soft water formulations containing alkanolamide and tridecyl alcohol derivatives were shown to be especially effective. At higher water-hardnesses, combinations containing sulfated ethoxylates of tridecyl alcohol and nonylphenol performed best. Optimum ethylene oxide content for the sulfated tridecyl alcohol ethoxylates has been shown to be 4 to 5 moles/mole of alcohol regardless of water hardness or detergent concentration. The alcohol ethoxylates were shown to be more tolerant of stronger sulfating agents with respect to product quality than the alkylphenol ethoxylates. Presented at the fall meeting, American Oil Chemists’ Society, Los Angeles. Calif., Sept. 28–30, 1959.     

High active alkyldimethylamine oxides

A recently developed, high active, alkyldimethylamine oxide powder now permits the use of this valuable surfactant in water-sensitive formulations such as bar soaps. Study of the various amine oxide homologs in key performance properties of soap bars showed them to be effective foam modifiers, plasticizers, and synergistic lime soap dispersants. The solid amine oxides were found to be a versatile additive which could readily be formulated into a wide variety of personal care bars.     

Effects of the ethylene oxide distribution on nonionic surfactant properties

Detergent-range primary alcohols are readily converted into nonionic surfactants by reaction with ethylene oxide. Optimum performance properties for these surfactants generally are attained by varying the number of moles of ethylene oxide reacted with each mole of alcohol or by altering the structure of the primary alcohol. However, variations in the ethoxylate-adduct distribution also affect surfactant properties in such a way that products with relatively narrow distributions possess features which are highly desirable in many household and industrial applications. For a given cloud point narrow-range ethoxylates have lower molecular weights and therefore lower pour points than broad-range surfactants. Because narrow-range ethoxylates contain less unreacted alcohol and other water-insoluble species, they are capable of forming aqueous solutions with much lower cloud points than their broad-range counterparts. Aqueous solutions of narrow-range products have lower viscosities, exhibit lower gel temperatures and remain fluid over a wider concentration range than solutions of broad-range surfactans. While the foams obtained with narrow-range surfactants in the Ross-Miles test are higher initially, they are less stable than those produced by conventional nonionic surfactants. Draves wetting data show that narrow-range products wet cotton substrates more efficiently than normal-distribution materials. Narrow-range ethoxylates exhibit higher aqueous surface tension and higher polyester adhesion tension values than their broad-range counterparts. In addition, narrow-range surfactants reduce the interfacial tension against paraffin oil more efficiently and more effectively than broad-range products. These results, along with laboratory detergency data, suggest that the use of narrow-range ethoxylates may lead to cleaning systems with improved performance and/or physical properties.     

Alcohol ether sulfates in shampoos

Mono-, di- and triethanolamine sulfates of several different molecular weight alcohol ether sulfates were formulated into shampoos. The ethylene oxide content of the alcohol ethoxylates varied from about 20 to 60%, although 40% was usual. The shampoo formulation was 20% active ether sulfate and 5% foam stabilizer. Lauric diethanolamide and amine oxides were used as foam stabilizers. The shampoos were tested for quality and quantity of foam, viscosity and cloud point. Although no “hair effects” tests were run, a limited home use test was made. Alcohol ether sulfate shampoos are equal or superior to several popular commercial products on the basis of a laboratory foam test. They are comparable in foam to alcohol sulfates in similar formulations. Cloud points of these shampoos were generally good. Amine oxide foam stabilizers reduced the cloud point more than the amide. Viscosities of the shampoos were readily controllable. Although the choice of alkanolamine, alcohol molecular weight and degree of ethoxylation had some effect on these properties, none were highly critical; this allows considerable leeway in their selection. The home use tests assured us that these shampoos were not obviously deficient in the desired “hair effect” properties. The literature records that alcohol ether sulfates are preferred to alcohol sulfates for low skin and eye irritation. By varying the free oil (unsulfated ethoxylate) content and making the proper choice of ether sulfate and foam stabilizer, bright and clear liquid shampoos with viscosities from about 10 centipoise to over 50,000 centipoise were made. The latter are essentially gels. Paste shampoos were also made from these ether sulfates. Presented at the AOCS Meeting, Chicago, October 1967. Now with Stepan Chemical Company, Northfield, Illinois.     

Foam enhancement by short-chain hydrophobe alcohol ethoxylates in light-duty liquids

This study examined linear alcohol ethoxylates as foam-enhancing agents in light-duty liquids. The ethoxylates were formulated as supplementary surfactants to an anionic main surfactant system. The relationship between ethoxylate structure and performance was elucidated, comparisons were made between ethoxylates and other recognized foam-enhancing agents, and a representative light-duty liquid formula was optimized. Performance evaluation focused on manual plate washing capacity but also included agitation foam volume, surface activity, cloud and clear temperatures, viscosity and grease cutting. Shortchain alcohol ethoxylates with a high degree of ethoxylation (such as C₈ with 70% or 7 moles of ethylene oxide) gave optimum performance that was comparable to or better than acknowledged foam-enhancing agents. The substitution of an alcohol ethoxylate for a fatty acid ethanolamide in the test formulation resulted in substantially lower formulation viscosity.     

Efficiency of Laundry Polymers Containing Liquid Detergents for Hard Surface Cleaning

Three 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.     

Optimization of nonionic/anionic surfactant blends for enhanced oily soil removal

Previously reported results for alcohol ethoxylate surfactants have shown that optimum removal of both nonpolar and sebum- like liquid soils from polyester/cotton fabric occurs at the phase inversion temperature (PIT) of the surfactant- water- soil system. A similar correlation between phase inversion and optimum detergency has been identified for detergent systems containing mixtures of nonionic and anionic surfactants such as alcohol ethoxylates and alcohol ethoxysulfates. Experimental techniques other than direct detergency studies are described which allow determination of the optimum nonionic/ anionic surfactant ratio for removal of a particular soil at a specified temperature. In addition, implications of these results for development of temperature- insensitive detergent formulations containing alcohol ethoxylates are discussed.     

Correlation between spray cleaning detergency and dynamic surface tension of nonionic surfactants

The role of temperature and dynamic surface tension (DST) in spray-cleaning processes in industrial applications was investigated with nonionic surfactants. Relative performance data for various ethoxylates (derived from primary alcohols or nonylphenol) were obtained by a spray-cleaning method. The spray-cleaning method was developed to screen and identify optimum surfactants, formulations, and conditions for spray-cleaning applications. It is introduced here as a means to mimic spray-cleaning processes by (timed) spraying of a cleaner solution under pressure onto a soiled substrate. Results of this investigation indicated that temperature and DST play major roles in the soil-removal process. Observed temperature trends are typical of nonionic surfactants’ clouding phenomena. Optimum cleaning was observed at specific temperatures. Also, nonionics with shorter hydrophobes exhibited the best detergency. Spray-cleaning detergency was compared to the DST because spray cleaning involves a dynamic interfacial process. New interfaces are constantly being created. Results showed that the surfactants with the lowest DST exhibited the best soil removal. This correlation can allow for a fast, cost-effective means for screening potential candidates and reducing development time for industrial spray-cleaning applications. Presented at the 85th Annual AOCS Meeting, May 8–12, 1994, Atlanta, Georgia.     

Effect of alkyl carbon chain length and ethylene oxide content on the performance of linear alcohol ethoxylates

A grid of 30 surfactants varying from C₈ to C₁₈ in carbon chain length and from 40 to 80% in ethylene oxide (EO) content were examined to determine the effect of molecular structure on the physical properties (density, melting point, solution viscosity) and performance properties (surface activity, detergency, hard-surface cleaning, foaming, wetting) of linear alcohol ethoxylates. Results show that while physical propeties are influenced primarily by EO content, both carbon chain length and EO content are important to performance. Optimum carbon chain length is also shown to depend strongly on surfactant concentration. Presented at the AOCS meeting in New Orleans in May 1987.     

Optimization of nonionic surfactants for hard-surface cleaning

The hard-surface cleaning performance of various nonionic homologs was evaluated as a function of carbon chain length, ethylene oxide (EO) content, blending and concentration. Results show carbon chain length to be very important to hard-surface cleaning. Performance significantly increases as carbon-chain length decreases, probably as a result of an increase in solvency properties as carbon chain length is decreased. EO content is also important, particularly if nonionics with longer carbon chain lengths are used. Surfactant concentration (dilution) has little effect on the optimum ethylene oxide content but significantly affects the optimum carbon chain length of the hydrophobe. With 5% homolog solutions, the optimally performing nonionic contains a C6 hydrophobe, but with 0.2% solutions, the optimal carbon chain length is shifted to the C8–C10 range. This is thought to result from a trade-off between the surfactant and solvent properties of the nonionic. Overall results show the optimal nonionic for hard-surface cleaning to consist of a blend of C6, C8 and C10 alcohols ethoxylated to a 50% EO level. Commonly used surfactant systems, e.g., alkylphenol ethoxylates and alkylphenol ethoxylate (APE)-butyl cellosolve (BC) blends, were also examined. Results show that alkylphenol ethoxylates give relatively poor performance compared with lower molecular weight linear nonionics because of the large size of their hydrophobe. Under concentrated use, a synergism does exist between APE and BC, but under dilute conditions, the addition of BC is ineffective. BC does not help the performance of low molecular weight nonionics. Surfactant-soil diffusion studies indicate that surfactant penetration of the soil may be the primary mechanism involved in the hard-surface cleaning of solid soils. Presented May 10, 1983, at the 74th Annual Meeting of the AOCS, Chicago, IL.     

Room Temperature Curing Epoxy Adhesives for Elevated Temperature Service,Part II: Composition,Properties, Microstructure Relationships

Low temperature curing epoxy formulations for elevated temperature service have been previously developed and studied (Part I¹). Balanced performance with respect to shear and peel properties have been obtained for a system composed of a tetra and trifunctional epoxy blend crosslinked by a mixture of multifunctional amine and an amino-terminated elastomer. In continuation of the previous study, the present one is aimed at investigation the effect of substitution of difunctional epoxy resin and curing agent for trifunctional ones on the developing microstructure and resulting mechanical properties. Furthermore, a new type of amino-terminated-acrylonitrile (ATBN) and an epoxy-terminated silane were included in the present investigation. Experimental results show that while reduction in the overall functionality of the reactants results in a lower lap shear strength, it gives rise to enhancement in peel strength. The same effect was observed when the new ATBN was used. Thermal analysis of the polymerization processes, taking place during curing of the various low temperature curing formulations, indicates that the curing activation energies are appreciably lower compared with high temperature curing systems. Addition of silane, ATBN and substitution of the multifunctional amine curing agent by a lower functional one, resulted in a moderate increase in the activation energy. The basic formulation, comprising a tetra- and trifunctional resin blend and a multifunctional amine and ATBN crosslinking mixture, developed a typical two-phase matrix-rubber microstructure. A third phase was observed when the trifunctional epoxy resin or the multifunctional curing agent was substituted by lower functional ones. A similar three-phase morphology was obtained when the epoxy-terminated silane was added to the basic treta- and trifunctional reactant system.     

Microwave-accelerated solvent-free aerobic oxidation of benzyl alcohol over efficient and reusable manganese oxides

A new facile and cost-effective process involving the solvent-free oxidation of benzyl alcohol using molecular oxygen as oxidant under controlled microwave irradiation has been developed for the production of chlorine-free benzaldehyde. Influence of different catalyst parameters (different manganese oxides and other kinds of transition metal oxides) and reaction conditions (reaction period and temperature) on the process performance has been studied. Under optimized reaction conditions, the MnO₂ catalyst showed a superior catalytic performance in the highly selective oxidation of benzyl alcohol as compared to other manganese oxide materials such as MnO, Mn₂O₃ and Mn₃O₄. Moreover, a very stable catalytic activity as a function of cycling test was observed for the MnO₂ catalyst.     

混合醇胺溶液吸收烟气中CO2

研究了温度、CO2含量与吸收液浓度对醇胺溶液吸收CO2性能的影响,并比较了不同复配体系对二异丙醇胺(MDEA)的活化效果。结果表明,醇胺溶液对CO2的吸收速率随反应时间的增加而降低,随吸收温度的升高而增强,以40℃为宜;吸收反应速率均随气、液相反应物含量增大而增强;混合体系对MDEA的活化效果为二乙烯二胺最好,乙醇胺最差。     

Reduction in pluming during the spray drying of a nonionic-based heavy duty powder

The plume observed during the spray drying of a nonionic-based heavy duty powder has been attributed to volatilization/recondensation of unethoxylated alcohols and other components in the alcohol ethoxylate. These “volatile components” comprise only 24–40% of the total spray tower emissions, but they are responsible for 85–95% of the observed opacity. Therefore, the relationship between observed opacity of the plume and particulate loading is not valid for the exhaust air from a spray tower producing nonionic-based powdered detergents. Alcohol ethoxylates are not decomposed to any measurable amount in a typical spray-dryer operation. The relative pluming tendency of alcohol ethoxylates depends exclusively on their relative vapor pressure. The vapor pressure of an alcohol ethoxylate is a function of the hydrophobe composition (starting alcohol) and the degree of ethoxylation which determines the level of unethoxylated alcohols. A new generation of alcohol ethoxylates with 60% less unethoxylated alcohol for a given ethoxylation level has been introduced recently. These Novel™ alcohol ethoxylates result in drastically improved pluming characteristics.     

水性环氧树脂应用性能研究

采用巴陵石化的自乳化性中分子质量水性环氧乳液CYDW-112W50及液体双酚A型环氧树脂CYDW-100与4种胺固化剂配制成4种水性体系,通过对涂膜物理、力学和耐腐蚀性的测试研究了不同固化体系和不同环氧与胺氢的配比对水性体系性能的影响。结果表明:离子型水性环氧体系硬度最高,附着力等比较优异,适合用于底涂或中涂;乳液型水性环氧体系柔韧性能较好,适合用于中涂和面涂;胺氢与环氧基团物质的量比为1.0～1.1∶1时,固化物综合性能最优,据此提出了防腐涂料及改性混凝土的参考配方,产品经性能测试达到使用要求。     

Room Temperature Curing Epoxy Adhesives for Elevated Temperature Service, Part II: Composition, Properties, Microstructure Relationships

Low temperature curing epoxy formulations for elevated temperature service have been previously developed and studied (Part I¹). Balanced performance with respect to shear and peel properties have been obtained for a system composed of a tetra and trifunctional epoxy blend crosslinked by a mixture of multifunctional amine and an amino-terminated elastomer. In continuation of the previous study, the present one is aimed at investigation the effect of substitution of difunctional epoxy resin and curing agent for trifunctional ones on the developing microstructure and resulting mechanical properties. Furthermore, a new type of amino-terminated-acrylonitrile (ATBN) and an epoxy-terminated silane were included in the present investigation. Experimental results show that while reduction in the overall functionality of the reactants results in a lower lap shear strength, it gives rise to enhancement in peel strength. The same effect was observed when the new ATBN was used. Thermal analysis of the polymerization processes, taking place during curing of the various low temperature curing formulations, indicates that the curing activation energies are appreciably lower compared with high temperature curing systems. Addition of silane, ATBN and substitution of the multifunctional amine curing agent by a lower functional one, resulted in a moderate increase in the activation energy. The basic formulation, comprising a tetra- and trifunctional resin blend and a multifunctional amine and ATBN crosslinking mixture, developed a typical two-phase matrix-rubber microstructure. A third phase was observed when the trifunctional epoxy resin or the multifunctional curing agent was substituted by lower functional ones. A similar three-phase morphology was obtained when the epoxy-terminated silane was added to the basic treta- and trifunctional reactant system.     

Ethylene oxide oligomer distribution in nonionic surfactants via high performance liquid chromatography (HPLC)

A high performance liquid chromatography (HPLC) method using adsorption columns combined with linear gradient elution has been developed for the determination of ethylene oxide (EO) distribution in nonionic surfactants. The quantitative ethoxylate adduct distribution in single-carbon-number and mixed-carbon-number primary alcohol-based samples can be obtained. The HPLC method is also applicable for determining the molar EO distributions in diverse ethylene oxide adduct compounds such as alkylphenol ethoxylates, branched alcohol ethoxylates and secondary alcohol ethoxylates. Nonionic surfactant samples containing adducts up to 25 mol have been successfully separated and the individual adducts quantitated.     

Long-term weathering behavior of UV-curable clearcoats: Depth profiling of photooxidation,UVA, and HALS distributions

The long-term weathering performance of two UV-curable clearcoat systems was studied using in-plane microtomy in combination with infrared spectroscopy, UV spectroscopy, and ESR spectroscopy. Oxygen transport characteristics were also studied using the half-time method. The photooxidation versus depth profile was highly dependant on the presence of hindered amine light stabilizers (HALS) for both coating systems. Ultraviolet light absorbers (UVA) had little effect on the photooxidation profile. A photooxidation gradient was formed in both clearcoats due to a reduction in oxygen solubility when compared to standard thermoset clearcoats. This gradient was only seen in formulations not containing HALS. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.