Calculation of HLB Values / Berechnung von HLB-Werten einiger Struktureinheiten von Emulgatoren

Sowada, Rudolf; McGowan, J. C.

doi:10.1515/tsd-1992-290208

Cited by 30 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, emulsifiers are classified on the basis of their HLB value [ 30 ]. This indicator is calculated based on the relative amounts of hydrophilic and lipophilic C types and functional groups to which a specific group contribution value is attributed [ 31 ]. The calculated HLB is reported for single surfactants with a definite known chemical composition, e.g., sodium oleate, polyethylene glycols, and sorbitans [ 30 ].…”

Section: Resultsmentioning

confidence: 99%

“…However, the γ-HLB correlation is consistent with the recommendation of Pasquali et al [ 32 ] to use the HLB parameter as an approximate guideline. Indeed, the group contribution values [ 31 ] used for the calculation of HLB ( Table S2 ) do not account for the change in polarity of a specific C type bonded to different functional groups. For example, in poly-functionalized C chains, the different functional groups may modify the hydrophilic or lipophilic properties of the product.…”

Section: Resultsmentioning

confidence: 99%

“…The major contributors to the higher HLB values were the NR and COX functional groups, to which the respective groups contribution number 9.4 and 2.2 were assigned. These numbers, taken from the literature [ 31 , 35 ], were tentatively used to calculate the HLB values for all products corresponding to the data points in Figure 6 . The two NR and COX functional groups accounted for about 65% of the total HLB value of the product ( Table S2 ).…”

Section: Resultsmentioning

confidence: 99%

“…In Equation (1), γ is the surface tension value measured at a 2 g/L concentration in water for several products with different molecular weights in the 30-750 kDa range obtained at different reaction times, and HLB is calculated (see Table S2) from the content of C type and functional groups obtained by 13 C spectroscopy (Figure 3) and from the specific group contribution number (gn) for each C type and functional groups reported in the specialized literature [31,34,35]. Figure 6 shows the γ vs. HLB plot for all fractions (Ri) obtained by membrane ultrafiltration of crude products obtained in trials No.0, No.3, and No.4 listed in Table 3 for the not-irradiated crude pristine SBP and the 10 fractions with molecular weights in the 30-750 kDa range obtained by ozonization of pristine SBP at different reaction times [12].…”

Section: The Products Hydrophilic Lipophilic Balance (Hlb)mentioning

confidence: 99%

See 3 more Smart Citations

A Low-Cost Ecofriendly Oxidation Process to Manufacture High-Performance Polymeric Biosurfactants Derived from Municipal Biowaste

Padoan,

Contillo,

Marafante

et al. 2024

Polymers

View full text Add to dashboard Cite

Biosurfactants account for about 12% of the global value of the surfactant market, which is currently dominated by synthetic surfactants obtained from fossil sources. Yet, the production of biosurfactants from renewable feedstock is bound to increase, driven by the increasing pressure from both society and governments for chemistry-based industries to become more ecofriendly and economically sustainable. A photo-chemical oxidation process is reported here, yielding new biosurfactants from urban biowaste in water that perform as a solvent and terminal oxidant reagent at room temperature without the addition of conventional oxidants and catalysts. Products with 200–500 kDa molecular weight are obtained. They lower the surface tension of water down to 34 mN/m at 0.5–2 g/L concentration. The estimated cost is rather low (0.1–1.5 EUR/kg), which is competitive with the cost of synthetic surfactants but much lower than the cost of the best-performing bacterial surfactants. For the implementation of the photo-chemical oxidation process at the industrial level, the results suggest that the new biosurfactants obtained in the present work may not reach the performance level of the best-performing bacterial surfactants capable of lowering the surface tension of water down to 28 mN/m. Yet, the biosurfactants produced by the photo-chemical process have a greater chance of being marketed on large scales.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: The Products Hydrophilic Lipophilic Balance (Hlb)mentioning

confidence: 99%

See 2 more Smart Citations

A Low-Cost Ecofriendly Oxidation Process to Manufacture High-Performance Polymeric Biosurfactants Derived from Municipal Biowaste

Padoan,

Contillo,

Marafante

et al. 2024

Polymers

View full text Add to dashboard Cite

show abstract

“…The concept of HLB values, first developed by Davies et al, is generally considered as a simple model to describe the solubility of surface-active compounds and their tendency to stabilize emulsions. − In this work, we used this model in order to calculate the HLB values of molecular clips and tweezers . Details of the calculations are described in the Supporting Information or in the literature. − The calculated values are summarized in Table .…”

Section: Introductionmentioning

confidence: 99%

Gemini-like Molecular Clips and Tweezers: The Influence of Structure and Guest Binding on Interfacial Tension

et al. 2009

View full text Add to dashboard Cite

In a series of experiments, we studied the interfacial activity of aromatic aliphatic molecules with rigid gemini-like structures at the interface between toluene and water. These molecules, called clips and tweezers, have rigid central benzene or naphthalene spacer-units, each substituted with two polar groups as well as two rigid aromatic side walls. They can serve as host molecules and selectively bind a variety of electron-deficient aromatic and aliphatic guest molecules. In different experiments, we compared the interfacial tensions with the calculated hydrophilic-lipid-balance (HLB) values of these molecules. The measured interfacial tensions depend as much on the HLB values as on the geometric structure of the water insoluble molecules. The concentration dependence of the surface tension gave evidence for the formation of inverse micellar aggregates, which were formed in the oil phase above a well-defined value of the bulk concentration. The presence of aggregates in the organic liquid could also be investigated by dynamic light scattering measurements. We observed typical diameters of the inverse micellar aggregates in the order of 5.6 nm, and the critical micelle concentrations (cmc's) coincided well with the results of interfacial tension measurements. From the surface excess in the vicinity of the cmc, we calculated the space occupied by a single clip molecule on the self-assembled monolayer. The observed molecular surface area was in agreement with the effective molecular diameters of the molecules. In additional experiments, we could also show that complexes with aromatic guest molecules such as 1,2-4,5-tetracyanobenzene (TCNB) led to a reduction of the amphiphilic clip properties.

show abstract

ChemInform Abstract: Palladium(0)‐Catalyzed Reactions of Nucleophiles with Allyl Carbonates of Unsaturated Fatty Acids

Schäfer¹,

Zobel²

2000

ChemInform

View full text Add to dashboard Cite

show abstract

Calculation of HLB Values / Berechnung von HLB-Werten einiger Struktureinheiten von Emulgatoren

Cited by 30 publications

References 0 publications

A Low-Cost Ecofriendly Oxidation Process to Manufacture High-Performance Polymeric Biosurfactants Derived from Municipal Biowaste

A Low-Cost Ecofriendly Oxidation Process to Manufacture High-Performance Polymeric Biosurfactants Derived from Municipal Biowaste

Gemini-like Molecular Clips and Tweezers: The Influence of Structure and Guest Binding on Interfacial Tension

ChemInform Abstract: Palladium(0)‐Catalyzed Reactions of Nucleophiles with Allyl Carbonates of Unsaturated Fatty Acids

Contact Info

Product

Resources

About