Compendium of the most significant studies with reference to properties, intake, effects.

Fiume, M. M., Bergfeld, W. F., Belsito, D. V., Hill, R. A., Klaassen, C. D., Liebler, D. C., ... & Heldreth, B. (2018). Safety assessment of tocopherols and tocotrienols as used in cosmetics. International journal of toxicology, 37(2_suppl), 61S-94S.

Abstract. The Cosmetic Ingredient Review (CIR) Expert Panel (Panel) assessed the safety of 14 tocopherols and tocotrienols and concluded these ingredients are safe as used in cosmetics....Tocopheryl acetate was (1) delivered in a triglyceride oil (caprylic/capric acid triglyceride); (2) surfactant-solubilized in water (PPG-26-buteth-26 and polyethylene glycol [PEG]-40 hydrogenated castor oil)...

Omelyanchuk, P. A., Vilinskaya, S. V., Timchenko, L. D., Rzepakovsky, I. V., Vakulin, V. N., & Sisonenko, M. N. (2014). Regenerating composition for skin care. Type: patent for invention Patent number: RU 2504359 C1 Patent Office: Russia Year of publication: 2014 Application number: 2012149562/15 Registration date: 11/21/2012Publication date: 1/20/2014 Patent holders: StavStandard Limited Liability Company

Abstract. .. invention relates to cosmetology and represents regenerating composition for skin care which contains regulator pH-triethanolamine, BAA, base Salcare SC80, cyclomethicone DC345, preservative, odorant, water, which is characterised by the fact, that as biologically active additive it contains protein substance from quail egg and antioxidant, and base includes UV-filter, olive oil, glycerin, emulsifier Solubilisant LRL preservative Sharomix MCI an purified water, and components in composition are in specified ratio in wt %....Solubilisant LRI - PPG-26-Buteth-26 (and) PEG-40 Hydrogenated Castor Oil. …

Liu, Z., Liao, T., Yang, N., Ding, L., Li, X., Wu, P., & Wang, P. (2021). Interventional Efects of the Topical of “Sanse Powder” Essential Oils Nanoemulsion on Knee Osteoarthritis in Rats by Targeting the ERS/TXNIP/NLRP3 Signaling Axis. Frontiers in Pharmacology, 2367.

Abstract. Our recent research is dedicated to finding effective drugs for the treatment of knee osteoarthritis (KOA) from traditional Chinese medicine and trying to make full use of modern science and technology to uncover the mechanisms and targets behind them....Briefly, firstly, the screened emulsifiers (tween-80, span-80), co-emulsifiers (octyldodecanol,PPG-26-Buteth-26), and BHT were mixed... 

STUDY OF COMPOSITION OF FRAGRANCE COMPOSITIONS AND ITS SOLUBILISATION IN SOLUTIONS OF NON-IONIC PAV Ivanova D.M., Bogdanova SA,Tuntseva S.N. - Vestnik Technologicheskogo Kazan National Research Technological University ISSN: 1998-7072

Abstract. This paper investigates solubilization of perfume compositions in alcohol-aqueous solutions in the presence of two solubilizers Eumulgin CO 410 (PEG-40 Hydrogenated Castor Oil) and Solubilizant LRI (a mixture of PEG-40 Hydrogenated Castor Oil and PPG-26-Buteth-26).

Johnson Jr, W. (2000). Final report on the safety assessment of PPG-12-Buteth-16, PPG-9-Buteth-12, PPG-26-Buteth-26, and PPG-28-Buteth-35. International Journal of Toxicology, 19, 47-67.

Abstract. Absent any data on the dermal absorption of a low-molecular-weight PPG Buteth, or actual data on skin irritation and sensitization, it was concluded that the available data are insufficient to support the safety of PPG-9-Buteth-12 or PPG-12-Buteth-16 in cosmetic products. Based on the available data, PPG-26-Buteth-26 and PPG-28-Buteth-35 are considered safe as used in cosmetic products. 

PPG-26-buteth-26 is a chemical compound, polyoxypropylene, polyoxyethylene ether of butyl alcohol by ethoxylation from ethylene oxide. It is a random linear copolymer with butanol that is produced from equal amounts (by weight) of ethylene and propylene oxide. 

The name describes the structure of the molecule:

• PPG-26. PPG stands for polypropylene glycol, a polymer derived from propylene oxide. The number '26' indicates the average number of repeating units of propylene oxide in the polymer chain. PPG-26 is a specific type of polypropylene glycol with 26 propylene oxide units.
• Buteth-26 is an ingredient that acts as a solubiliser and emulsifier. It consists of a butyl group (C4H9-) linked to an ether group (-O-) and a hydroxyl group (-OH). The number '26' in the name indicates that it is a specific butyl variant or version.

Description of raw materials used in production

• Ethylene oxide - A key raw material used in the production of polyethers like PPG.
• Butyl alcohol - The ethylene oxide will react with this alcohol to form the desired compound.

The synthesis process takes place in different steps:

• Formation of the PPG derivative. Polypropylene glycol (PPG) is modified to form a derivative that can further react to produce PPG-26-buteth-26. This modification step may involve the functionalisation of the PPG molecule through reactions such as esterification, etherification or other chemical transformations. The specific reactions and reagents used depend on the desired properties and structure of the final compound.
• Butylation. The modified PPG derivative undergoes butylation, in which a butyl group (C4H9) is attached to the molecule. This step typically involves the reaction between the modified PPG and a suitable butylating agent, such as butyl bromide or butyl chloride. Reaction conditions may vary depending on the specific synthesis method.
• Purification. After butylation, the crude product obtained may contain PPG-26-butyl-26 together with impurities. Purification techniques such as distillation, extraction or filtration can be used to isolate PPG-26-buteth-26 and remove impurities. These purification methods help ensure a higher level of purity of the final compound.
• Characterisation and analysis. Once purified, the synthesised PPG-26-buteth-26 must be characterised and analysed to confirm its chemical structure and purity. Techniques such as NMR, MS and IR spectroscopy can be used to analyse the structure and verify the identity of the synthesised compound.

It appears as an oily transparent liquid or white powder..

What it is used for and where

Cosmetics

Hair conditioning agent. A significant number of ingredients with specific and targeted purposes may co-exist in hair shampoo formulations: cleansers, conditioners, thickeners, matting agents, sequestering agents, fragrances, preservatives, special additives. However, the indispensable ingredients are the cleansers and conditioners as they are necessary and sufficient for hair cleansing and manageability. The others act as commercial and non-essential auxiliaries such as: appearance, fragrance, colouring, etc. Hair conditioning agents have the task of increasing shine, manageability and volume, and reducing static electricity, especially after treatments such as colouring, ironing, waving, drying and brushing. They are, in practice, dispersants that may contain cationic surfactants, thickeners, emollients, polymers. The typology of hair conditioning agents includes: intensive conditioners, instant conditioners, thickening conditioners, drying conditioners. They can perform their task generally accompanied by other different ingredients.

Skin conditioning agent. It is the mainstay of topical skin treatment as it has the function of restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants that can be added in the formulation.

Also used as emulsifier, with a risk factor of 2 it is therefore safe to use and generally has no effect on pregnant women.

Other uses

Components of adhesives; antifoaming agents in papermaking, animal glue and antifoaming agents in papermaking as components of packaging boards

Rubber lubrication; heat transfer fluids and special solvents.

Safety

The dioxane content is less than 5 ppm and the ethylene oxide content less than 1 ppm according to CIR (1).

For more information:   

 PPG-26-buteth-26 studies

• Molecular Formula    C₉H₂₀O₃
• C₄Hg(OCHCH₂)x(OCH₂CH₂)yOH  CH₃
• Molecular Weight     176.25
• CAS  9065-63-8   9038-95-3
• UNII    2II1K6TZ4P
• EC Number   
• DSSTox Substance ID  
• IUPAC  2-(1-butoxypropan-2-yloxy)ethanol
• InChI=1S/C9H20O3/c1-3-4-6-11-8-9(2)12-7-5-10/h9-10H,3-8H2,1-2H3 
• InChl Key      AAOFEMJZTYQZRH-UHFFFAOYSA-N
• SMILES   CCCCOCC(C)OCCO
• MDL number  
• PubChem Substance ID    
• SCHEMBL8617152   

References_________________________________________________________________________

(1) FR340.tif (personalcarecouncil.org)