Oxyethylene Units Research Articles

Enhanced photovoltaic performances of dye-sensitized solar cell using self-charring phosphate ester surfactant

In this article, we describe the use of Triton™ X-based surfactants with an octyl phenol ethoxylate (OPE) backbone and a phosphate ester chain end as a dispersant for formulating TiO 2 paste. Three phosphate-terminated Triton™ X (or OPE) derivatives, i.e. [OPE2-OPO(OH) 2], [OPE5-OPO(OH) 2], and [OPE10-OPO(OH) 2] are prepared from OPEs of different oxyethylene units and phosphorous pentoxide. The phosphate-terminated Triton™ X of the highest number of oxyethylene units ( i.e. OPE10-OPO(OH) 2) provides the desirable amount of char (9 wt.%) at 600 °C under air atmosphere, and is found to lower the viscosity of [TiO 2/ethyl cellulose/terpineol] paste, leading to finer and more close-packed TiO 2 film after firing. The photoanode film prepared by the TiO 2 paste was built up on a conducting glass plate by a screen printing process followed by a heat treatment for sintering. Then, the TiO 2 film showed not only higher particle density, but also residual char on the particle surface in comparison with the control sample film prepared from the [TiO 2/ethyl cellulose/terpineol] paste with no dispersant. The dye-sensitized solar cell (DSSC) employing the prepared nanocrystalline TiO 2 film with char exhibits significantly improved photovoltage and photocurrent characteristics under 1 sun illumination.

Preliminary characterisation of LiAsF 6 hybrid polymer electrolytes for electrochromic devices

In this exploratory study the results of characterisation of a poly(oxyethylene) (PEO)/siloxane hybrid network electrolyte doped with lithium hexafluoroarsenate (LiAsF 6) are described. In accordance with convention, the lithium salt concentration is expressed in terms of the number of oxyethylene units in the organic component of the host network per Li + ion guest species. Samples of solvent-free electrolytes were prepared with a range of guest salt concentration using the sol–gel process. Hybrid materials based on LiAsF 6, were obtained as mechanically robust, flexible, transparent and completely amorphous films and characterised by conductivity measurements, thermal analysis and electrochemical stability. Preliminary characterisation of electrochromic devices (ECDs) incorporating optimised LiAsF 6-doped di-ureasil compositions has confirmed that these electrolytes perform satisfactorily as multifunctional component layers in this application.

Solubility of Nonsteroidal Anti-inflammatory Drugs (NSAIDs) in Aqueous Solutions of Non-ionic Surfactants

The solubilities of two nonsteroidal anti-inflammatory (MELOXICAM and CELECOXIB) drugs, were determined in aqueous solutions of nonionic (Tween 20, Tween 80, Brij 30, Brij 35, Triton X 100, Triton X 114) surfactants. These surfactants have different numbers of oxyethylene units and their micelles showed different aggregation numbers. It is shown that these surfactants have different abilities to solubilize NSAIDs drugs. The solubilities of the drugs increased linearly with the increase in concentration of surfactants. The sizes of micelles remained constant with the addition of the drugs, except for Triton type surfactants in which case the size of the micelles decreased. It was observed that the number of oxyethylene units in the surfactants, aggregation number of the micelles and HLB play key roles in solubilizing the drugs.

Synthesis and Properties of Novel Double‐Tail Trisiloxane Surfactants with High Spreading Ability

AbstractA new type of double‐tail trisiloxane surfactants of the general formula R1NR2CH2CH(OH)CH2O(CH2CH2O)xCH3 (x = 8.4, 12.9, 17.5, 22; R1 = Me3SiOSiMe(CH2)3OSiMe3, R2 = CH2CH(OH)CH2OR3, R3 = CH2CH(C2H5)CH2(CH2)2CH3) has been synthesized by reacting single‐tail trisiloxane surfactants with 2‐ethylhexyl glycidyl ether. Their structures were characterized with 1H‐NMR and 13C‐NMR spectroscopy. These double‐tail trisiloxane surfactants reduce the surface tension of water to less than 24 mN/m at a level of 10−5 mol/L. The spreading ability (SA) of the double‐tail trisiloxane surfactant solution on Parafilm (or Ficus microcarpa leaf) surfaces is better than that on polyethylene terephthalate surface. The SA of the solution of the double‐tail trisiloxane surfactants 1J with average ethoxy units of 8.4 is far better than the others, and its solution (5.0 × 10−3 mol/L) possesses an SA value of over 15 within 10 min on Parafilm and Ficus microcarpa leaf surfaces. The surface tension values of aqueous solutions (1.0 × 10−3 mol/L) of the double‐tail trisiloxane surfactants 1J are still less than 25 mN/m over 21 days in an acidic environment (pH 4.0) and 139 days in an alkaline environment (pH 10.0), respectively. It is suggested that the SA and hydrolysis resistance of double‐tail trisiloxane surfactants are able to be improved by changing the structure of the hydrophobic group, such as increasing the molar ratio of methyl to methylene.

Degradation of Two Persistent Surfactants by UV‐Enhanced Ozonation

AbstractIn this study the treatment efficiency of different ultraviolet (UV)‐enhanced ozonation processes for degradation of two surfactants, sodium dodecylbenzene sulfonate [200 mg/L or 0.3 critical micelle concentration (CMC)] and a nonylphenol ethoxylate with 40 oxyethylene units (200 mg/L ∼0.5 CMC), were investigated in laboratory‐scale experiments at ambient temperature. The absorbance band of the aromatic ring of the surfactants was monitored during the oxidation process. The reduction in chemical oxygen demand (COD) and total organic carbon (TOC) of the surfactant solution was evaluated. The results showed that a combination of UV irradiation and ozonation was considerably more efficient than the individual processes (at least two times more efficient in terms of COD and TOC reductions). The synergistic effect of ozonation and UV irradiation was particularly pronounced when medium‐pressure UV irradiation was used. By adding alkali to the solution, the efficiency of the UV‐enhanced ozonation increased with respect to COD reduction but decreased with respect to TOC reduction. This indicates partial oxidation with lower degree of mineralization of the surfactants.

Partition coefficients of salicylic acid between water and the micelles of some non-ionic surfactants

Abstract Partition coefficients of ionized and unionized salicylic acid molecules between water and the micelles of several non-ionic surfactants have been determined. Those of unionized molecules decreased with decreasing length of the surfactant alkyl chain and with increasing length of the surfactant polyoxyethylene chain. Ionized salicylic acid partitioned to a significant extent only into those surfactants having more than approximately 44 oxyethylene units in their hydrophile. The findings are discussed in terms of their biopharmaceutical significance.

Safety aspects of non-ionic surfactant vesicles: a toxicity study related to the physicochemical characteristics of non-ionic surfactants.

Two different toxicity models were used to assess the relationship between the physicochemical properties of non-ionic surfactant vesicles (NSVs), and the safety of these vesicles for topical drug administration. The vesicles used in this study consisted of polyoxyethylene alkyl ethers (CnEOm) in which the number of C atoms (n) varied between 12 and 18 and the number of oxyethylene units (m) between 3 and 7. The physicochemical properties of the vesicles are described in terms of hydrophilic-lipophilic balance (HLB) values, and critical micelle concentrations (CMC), and the rigidity of the bilayers as determined by the gel-liquid transition temperatures and the cholesterol content of the bilayers. The first toxicity model, comprising the measurement of the ciliary beat frequency, is a tool to assess the safety of intranasally applied formulations. Studies using this ciliotoxicity model revealed that by increasing the length of the alkyl chain of the surfactant, a decrease in toxicity was observed. The opposite correlation was found if the length of the polyoxyethylene headgroup was increased. Furthermore, it was observed that gel-state vesicles produce less of an effect on the ciliary beat frequency than liquid state vesicles. The second toxicity model, comprising the determination of cell proliferation of human keratinocytes, is a method to assess skin irritancy. In contrast to the ciliotoxicity model the length of the polyoxyethylene headgroup and of the alkyl chains did not seem to have an effect on the safety of the vesicles.(ABSTRACT TRUNCATED AT 250 WORDS)

Structure of vesicles formed from non-ionic dialkylglycerol poly(oxyethylene) ether surfactants: effect of electrolyte and cholesterol

Five non-ionic dialkylglycerol poly(oxyethylene) ether surfactants, designated 2C m E n (where m, the number of carbons in each alkyl chain = 16 or 18, and n, the number of oxyethylene units = 12, 16 or 17) have been examined for their ability to form vesicles when dispersed in water or in an aqueous solution of 154 mM NaCl, alone or in the presence of 50 mol% cholesterol. Freeze fracture electron microscopy and light scattering showed that regardless of the hydrating fluid, all the non-ionic surfactants, with the exception of 2C 16E 17 and 2C 18E 17, formed vesicles in the absence of cholesterol – 2C 16E 17 and 2C 18E 17 instead formed micellar aggregates. All surfactants, however, formed vesicles in the presence of 50 mol% cholesterol. Small angle neutron scattering studies of the surfactant vesicles enabled the bilayer thickness and repeat distance ( d-spacing) to be determined. The bilayers formed by all the non-ionic surfactants in the absence of cholesterol were surprisingly thin (∼50 Å for the E 12 containing surfactants and ∼64 Å for 2C 18E 16) most likely due to the intrusion of oxyethylene groups into the hydrophobic core of the bilayers. In contrast, however, the non-ionic surfactants exhibited a relatively large d-spacing of around ∼130–150 Å. The addition of 50 mol% cholesterol had a dramatic effect on the thickness of the vesicle bilayer, increasing its size by 10–20 Å, most probably because of an extrusion of oxyethylene from the hydrophobic region of the bilayer and/or a reduction in the tilt on the surfactant alkyl chains. Additionally the presence of cholesterol in a vesicle tended to reduce slightly both the d-spacing and the thickness of the water layer separating the bilayers. The presence of NaCl, even at the low concentrations used in the study, did affect the properties of the bilayer such that it reduced the d-spacing and, in the case of cholesterol-containing systems, also reduced bilayer thickness.

Syntheses and properties of ethoxylated double-tail trisiloxane surfactants containing a propanetrioxy spacer

A new type of ethoxylated double-tail trisiloxane surfactants containing a propanetrioxy spacer of the general formula ROCH2CH(OR)CH2O(CH2CH2O)xCH3 [R = Me3SiOSiMe(CH2)3OSiMe3, x = 8.4, 12.9, 22] has been synthesized. Their structures were characterized by 1H-NMR, 13C-NMR and 29Si-NMR spectroscopy. The critical micelle concentration (CMC) values of these double-tail trisiloxane surfactants were at the level of 10−5 mol l−1, and the surface tension values of their aqueous solutions at CMC were in the range of 21-24.9 mN m−1. Only the double-tail trisiloxane surfactant with average ethoxy units of 8.4 (1P) possesseda good spreading ability (SA) value. Its SA values of aqueous solutions (5.0 × 10−3 mol l−1) on parafilm and Ficus microcarpa leaf surfaces were more than 15 (within 10 min) and 13 (within 3 min), respectively. The trisiloxane surfactant 1P was also found to have the strongest hydrolysis resistant ability among all of the double-tail trisiloxane surfactants prepared. Its aqueous solutions were stable for 130 days in an acidic environment (pH 4.0) and 59 days in an alkaline environment (pH 10.0) with surface tension values less than 23 mN m−1. It is suggested that this surfactant can be used as a wetting agent or spreading agent in certain extreme pH environments. Copyright © 2011 John Wiley & Sons, Ltd.

Synthesis and gas permeability of ester substituted poly( p-phenylene)s

Polymerizations of various ester substituted 2,5-dichlorobenzoates [substituent: linear alkyl groups ( 1a– f), branched alkyl groups ( 1g– l), cyclohexyl groups ( 1m– o), phenyl groups ( 1p– r), and oxyethylene units ( 1s– v)] were investigated with Ni-catalyzed/Zn-mediated system in 1-methyl-2-pyrrolidone (NMP) at 80 °C. Most of monomers bearing linear and branched alkyl groups successfully polymerized to give relatively high-molecular-weight polymers ( M n = 10,000–20,800). However, the molecular weight of the polymer having eicocyl groups was low because of steric hindrance of long alkyl chain. The polymerizations of cyclohexyl 2,5-dichlorobenzoate and phenyl 2,5-dichlorobenzoate produced low-molecular-weight polymers, while the polymerizations of monomers with alkyl cyclohexyl and alkyl phenyl groups proceeded to afford polymers with relatively high-molecular-weights. The polymers possessing oxyethylene units were obtained, but the molecular weights were low when the oxyethylene chains were long. The gas permeability of membranes of poly( p-phenylene)s with alkyl chains increased as increasing the length of alkyl chain. The membranes of poly( p-phenylene)s with phenyl groups and oxyethylene units exhibited high densities and relatively low gas permeability. However, the CO 2/N 2 separation factor of membrane of poly( p-phenylene) having oxyethylene units was as large as 73.6.

Syntheses and Properties of New Double-tail Trisiloxane Surfactants with Both Hydrolysis Resistance and High Spreading Ability

Abstract New double-tail trisiloxane surfactants of the general formula R1NR2CH2CH(OH)CH2O(CH2CH2O)xCH3 (R1 = Me3SiOSiMe(CH2)3 · OSiMe3; R2 = Me3SiOSiMe((CH2)3OCH2CH(OH)CH2)OSiMe3; x = 8.4, 12.9, 17.5, 22) have been synthesized. The spreading ability (SA) values of the double-tail trisiloxane surfactants solutions (1.0 × 10−3 mol/L) with average ethoxy units of 8.4, 12.9 and 17.5 on ficus microcarpa leave surface are more than 9 within 3 minutes, and their SA values on the parafilm surface are over 15 within 10 minutes at a concentration of 5.0 × 10−3 mol/L. In alkaline environment (pH = 10.0) the hydrolysis resistant ability (HRA) of the double-tail trisiloxane surfactant containing average ethoxy units of 8.4 with the surface tension of aqueous solution (1.0 × 10−3 mol/L) of less than 23 mN/m over 170 days, is far better than the others’. It is suggested that a more flexible spacer between hydrophobic groups and hydrophilic groups in double-tail trisiloxane surfactants molecules, not only can improve their SA on low-energy solid surfaces, but also improve their HRA.

Unique liquid crystal behavior in water of anionic fluorocarbon–hydrocarbon hybrid surfactants containing oxyethylene units

This study reports the unique aqueous lyotropic liquid crystal behavior of an anionic hybrid surfactant, 8F-B2ES, which has 2-[2-(butyloxy)ethyloxy]ethyl and 1H,1H,2H,2H-perfluorodecyl tails. An 8F-B2ES-analog hybrid surfactant with no oxyethylene units (8F-DeS) and a symmetric fluorinated double-tail surfactant with two 2-(1H,1H,2H,2H-perfluorohexyloxy)ethyl tails (4FEOS) were used as control surfactants in examining the effects of the oxyethylene units and of the hybrid structure on the liquid crystal behavior. Polarized microscopic observations showed the formation of a lamellar liquid crystal phase for each surfactant/water mixture at surfactant concentrations higher than 10wt.%. In the case of the 30wt.% 8F-B2ES/water mixture, two types of spherical aggregates were observed at temperatures higher than 40°C: one was a typical lamella liquid crystal with a maltese cross-texture, and the other was optically isotropic. Interestingly, when the 8F-B2ES lamellar phase was cooled to below 40°C, the lamellar aggregates were distorted and the isotropic droplets became anisotropic. As this unique liquid crystal behavior was not observed for aqueous mixtures of the control surfactants, the oxyethylene units in the hybridized hydrocarbon tail play an important role in the behavior. This study also examined the effect of the oxyethylene units on microenvironmental polarity in the hybrid surfactant bilayer via fluorescence spectral measurements of pyrene solubilized in each lamellar phase. The polarity of the 8F-B2ES bilayer at 70°C was found to be that of a hydrocarbon surfactant lamellar phase, and increased gradually with decreasing temperature. The polarity became the same as that of hydrophilic spherical micelles below 40°C, despite the presence of the lamellar aggregates. Since the polarity in the 8F-DeS bilayer was independent of temperature, and as low as that of a typical hydrocarbon surfactant bilayer, hydration of the 8F-B2ES oxyethylene units would increase the polarity, and then loosen the 8F-B2ES packing within the bilayer. This probably led to distortion of the lamellar aggregates.

Synthesis of Thermo-Responsive Fluorinated Star-Shaped Polymers by Living Cationic Polymerization

ABSTRACTWell-controlled fluorinated star-shaped polymers with oxyethylene units were designed and synthesized by living cationic polymerization. These fluorinated star-shaped polymers were prepared using successive fluorinated initiators to generate fluorinated, end-functionalized and hydrophilic segments with oxyethylene. Poly(vinyl ether)s with oxyethylene units are known to be thermo-responsive polymers that exhibit a lower critical solution temperature (LCST) in aqueous solutions. These novel fluorine-containing star-shaped polymers with oxyethylene were also thermo-responsive, as expected. In addition, the hetero-fluorinated star-shaped polymers with oxyethylene segments and different fluorine compositions were synthesized with various bifunctional initiators by living cationic polymerization having narrow molecular weight distributions (Mw/Mn=1.23−1.29) and contained very little, if any, presence of the linear homopolymer precursor, as evidenced by GPC. The LCST of this polymer depended on the end group fluorine composition and significant changes in cloud points were observed in water, as confirmed by static light scattering (SLS) measurements. As an example, aqueous solutions the star-shaped polymers without fluorine terminal groups showed no cloud point below up to 60 ºC in aqueous solution. After the fluoro-functionality was incorporated into the terminal groups, the cloud point of the aqueous solutions decreased to almost 20 ºC.

Low-melting zwitterion: effect of oxyethylene units on thermal properties and conductivity

An imidazolium-based zwitterion containing two oxyethylene units was obtained as a colorless liquid at room temperature. The equimolar mixture of the liquid zwitterion and lithium bis(trifluoromethylsulfonyl)amide showed an ionic conductivity of over 10(-4) S cm(-1) at 80 °C, which was higher than those of mixtures composed of analogous solid zwitterions.

Nanocomposites based on borate esters as improved lithium-ion electrolytes

Borate esters with different lengths of ethyleneoxy units were investigated as electrolyte solvents for lithium salts such as lithium triflate, perchlorate, bis(trifluoromethanesulfonyl)imide, bis(pentafluoroethanesulfonyl)imide and bis(oxalato)borate. The ionic conductivity of the salt solutions was measured to be of the order of 10−3 to 10−4 S cm−1 at room temperature. Transference number measurements for the borate ester–lithium perchlorate system indicated roughly equal contributions of cations and anions to the total conductivity, while the borate ester–lithium bis(oxalato)borate showed predominant anionic conductivity. Nanocomposite electrolytes were prepared by heterogeneous doping of the borate esters with silica. Composites with 10 nm silica particles exhibited low-viscous electrolyte behavior with a clear but modest conductivity enhancement at very low volume fractions of silica and a depression of the conductivity value at higher volume fractions. In the case of fumed silica (7 nm) the nanocomposites had at a sufficiently high volume fraction and a jelly, transparent appearance with the favorable mechanical properties of a high-viscous semi-solid without noteworthy decrease in the Li ion conductivity. In particular the last material with its combination of favourable electrical, mechanical and optical properties, promises to be a viable candidate for various applications (Li-based batteries, solar cells).

Effect of Oxyethylete Units on Adsorption and Micellization Properties of Novel Benzene Sulfonate Surfactants

The surface tension and fluorescence spectra of sodium octyl-[ω-octyloxy-poly(oxyethylene)]-yl-benzene sulfonates (APEnBS) aqueous solutions have been investigated by Wilhelmy plate method and intrinsic probe methods, respectively to study the effect of EO units on their properties. It was discovered that the surface performance of these surfactants was greatly outstanding: the values of critical micelle concentration (CMC) reached to be of the order of magnitude of 10−5 mol/L, the values of surface tension at CMC, γCMC, were between 25.79 to 31.02 mN/m, and the effectiveness and efficiency of surface tension reduction were excellent. The introduction of oxyethylene units to the surfactant molecule evidently improved the solubility of APEnBS. With the increase in EO units, the CMC slightly changed after the first decreased. On the other hand, the surface excess concentration at saturation, Γ max, decreased after the first increased and γCMC increased after the first decreased accordingly. The CMC determined by fluorescence spectra of intrinsic probe method were accorded with the CMC measured by surface tension method. The aggregation number N, characterized by quenching the fluorescence spectra with methyl viologen (MV2+) as the extrinsic quencher, gradually decreased first (from 0 to1) and then slightly changed (from 1 to 4) with increasing EO chain length. So we concluded that the appropriate number of EO units was the key factor to get the best physicochemical properties of APEnBS.

Solvent-Controlled Metal Ion Binding Selectivity and Anion Interaction of the Acridinedione-Based Heteroditopic Host

Acridinedione-based heteroditopic hosts 1a-c, which contain a flexible oxyethylene moiety as a metal ion binding site and amino hydrogen as an anion receptor unit, were synthesized and characterized. Metal ion and anion binding studies were carried out in different solvents to understand the solvent-induced selectivity of the metal ion binding and anion interactions. In acetonitrile, Ca(2+) alone shows a binding with the oxyethylene unit and -OCH(3) group, which results in a fluorescence enhancement without any spectral shift due to the suppression of the photoinduced electron transfer (PET) process. In chloroform, in addition to Ca(2+), Na(+) also shows a fluorescence enhancement with a 14 nm red shift in the emission maximum. (1)H NMR titration studies confirm that the addition of Na(+) does not involve binding at the oxyethylene moiety, while it shows a binding at the acridinedione carbonyl group and -OCH(3) group, which results in the red shift and fluorescence enhancement, respectively. In the anion interaction studies, F(-) shows a neat deprotonation in polar aprotic solvents, whereas in chloroform, it shows a H-bond complex due to the lower anion desolvation energy. The present study clearly signifies the role of solvent in metal ion selectivity, which is an often unnoticed parameter in metal ion binding.

Equilibrium and surface rheology of two polyoxyethylene surfactants (C iEO j) differing in the number of oxyethylene groups

A study of equilibrium adsorption properties and surface dilational rheology of two polyoxyethylene surfactants of technical grade have been carried out. It has been shown, that equilibrium adsorption and surface rheology are greatly influenced by the oxyethylene chain. To explore the equilibrium properties, a pendant drop profile tensiometer was used. The equilibrium surface pressure isotherms can be explained in the framework of the reorientation model. The increase in the number of oxyethylene units leads to higher surface activity at low concentration when the surfactants adsorb in the state of maximum molar area. However, at higher concentration the adsorbed surfactant molecules reorient to a state of minimum molar area. In this state the surface activity is, on contrary, lower for C 10EO 14 due to higher hydrophilicity. Dilational rheology was studied by means of the oscillating drop method. The surfactant with higher EO units showed an enhanced elasticity. Moreover, whereas C 10EO 6 experimental data can be interpreted on the basis of the diffusional theory and a diffusion coefficient of 4 × 10 −10 m 2 s −1 was estimated, C 10EO 14 behavior is more complex maybe due to the multitude of possible adsorption conformations and is closer to that expected for polymer surfactants.

A modified supported bilayer/diblock polymer – Working towards a tunable coating for capillary electrophoresis

A surfactant bilayer/diblock polymer coating was previously developed for the separation of proteins. The coating consisted of a mixture of the cationic surfactant dioctadecyldimethylammonium bromide (DODAB) and the neutral polymer poly-oxyethylene (POE) 40 stearate (Journal of Chromatography A 1130 (2006) 265–271). Herein an improved method of generating DODAB/POE stearate coatings is demonstrated, which yields more predictable EOF, more stable coatings, greater average efficiencies and easier method development. In this sequential preparation method the DODAB is first flowed through the capillary, followed by a flow of the POE stearate (sequential method). A tunable EOF (−2.40 to −0.17×10−4cm2/Vs) is achieved by varying the POE chain length (8, 40 and 100 oxyethylene units). Mixtures of POE 8 and POE 40 stearate enabled continuous variation in EOF from −2.44 to −0.42×10−4cm2/Vs. Separations of basic proteins yielded efficiencies of 760000–940000plates/m. Coatings formed using the sequential method were more stable over a larger number of runs (%RSD for migration times: 0.7–1.0% over 30 runs) than those formed using the original mixed method (%RSD: 2.4–4.6% over 14 runs). The ability to tune the EOF is important in maximizing the resolution of analytes with similar electrophoretic mobilities. Histone proteins are separated on a sequentially coated capillary with resolution of nine possible subtypes. Acidic proteins are separated on a sequentially coated capillary at pH 6.4.

The polydispersity effect of distributed oxyethylene chains on the cloud points of nonionic surfactants

The cloud points of aqueous solutions containing polyoxyethylene surfactant molecules with a distribution of chain lengths were studied for several nonionic surfactants. Experimentally, the cloud points increased as the oxyethylene chain lengths increased with a linear or logarithmic relation of the number of oxyethylates, as proposed by Schott. An experimental scale, the p-Po scale, was previously developed to correspond to the cloud points, where p is the average number of oxyethylene units per molecule and Po is the shortest chain length reference. However, no previous prediction methods of cloud point addressed systems containing a range of chain lengths. In this work, we propose a rescaling of the representative chain length as s-Po, where s is the cloud point-weighted mean ethylene oxide chain below p, and approximated as (p-Po)/PDI where PDI is the polydispersity index. Using the rescaled length, the experimental data for C(12)Es (lauryl alcohol ethoxylate, LAE), NPE-10 (nonyl phenol ethoxylate) and TDE-10 (tridecyl alcohol ethoxylate) were successfully predicted with no additional parameters, such as {(p-Po)/(PDI)}/CP=a+b{(p-Po)/(PDI)}, where PDI indicates the Broadness of the chain length distribution.