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

Liñeira Del Río JM, López ER, González Gómez M, Yáñez Vilar S, Piñeiro Y, Rivas J, Gonçalves DEP, Seabra JHO, Fernández J. Tribological Behavior of Nanolubricants Based on Coated Magnetic Nanoparticles and Trimethylolpropane Trioleate Base Oil. Nanomaterials (Basel). 2020 Apr 5;10(4):683. doi: 10.3390/nano10040683.

Kramer S, Krajnc P. Hierarchically Porous Microspheres by Thiol-ene Photopolymerization of High Internal Phase Emulsions-in-Water Colloidal Systems. Polymers (Basel). 2021 Sep 30;13(19):3366. doi: 10.3390/polym13193366.

Teixeira RA, Flores DHÂ, da Silva RCS, Dutra FVA, Borges KB. Pipette-tip solid-phase extraction using poly(1-vinylimidazole-co-trimethylolpropane trimethacrylate) as a new molecularly imprinted polymer in the determination of avermectins and milbemycins in fruit juice and water samples. Food Chem. 2018 Oct 1;262:86-93. doi: 10.1016/j.foodchem.2018.04.076.

Acosta Ortiz R, Reinoza Dávila JA, Guerrero Santos R. Development of Photocurable Polyacrylate-Based PolyHIPEs and the Study of the Kinetics of Photopolymerization, and of Their Thermal, Mechanical and Hydrocarbon Absorption Properties. Polymers (Basel). 2021 Oct 12;13(20):3497. doi: 10.3390/polym13203497.

Ashurov M, Abdusatorov B, Baranchikov A, Klimonsky S. Surface-enhanced Raman scattering in ETPTA inverse photonic crystals with gold nanoparticles. Phys Chem Chem Phys. 2021 Sep 22;23(36):20275-20281. doi: 10.1039/d1cp02958d.

Chen C, Garber L, Smoak M, Fargason C, Scherr T, Blackburn C, Bacchus S, Lopez MJ, Pojman JA, Del Piero F, Hayes DJ. In vitro and in vivo characterization of pentaerythritol triacrylate-co-trimethylolpropane nanocomposite scaffolds as potential bone augments and grafts. Tissue Eng Part A. 2015 Jan;21(1-2):320-31. doi: 10.1089/ten.TEA.2014.0018.

Wada K, Ikeda E, Wada J, Inoue G, Miyasaka M, Miyashin M. Wear characteristics of trimethylolpropane trimethacrylate filler-containing resins for the full crown restoration of primary molars. Dent Mater J. 2016;35(4):585-93. doi: 10.4012/dmj.2015-149.

Kitagawa H, Takeda K, Kitagawa R, Izutani N, Miki S, Hirose N, Hayashi M, Imazato S. Development of sustained antimicrobial-release systems using poly(2-hydroxyethyl methacrylate)/trimethylolpropane trimethacrylate hydrogels. Acta Biomater. 2014 Oct;10(10):4285-95. doi: 10.1016/j.actbio.2014.06.016.

Sharma A, Thongrom B, Bhatia S, von Lospichl B, Addante A, Graeber SY, Lauster D, Mall MA, Gradzielski M, Haag R. Polyglycerol-Based Mucus-Inspired Hydrogels. Macromol Rapid Commun. 2021 Oct;42(20):e2100303. doi: 10.1002/marc.202100303.

Gama MR, Aggarwal P, Lee ML, Bottoli CBG. Controlled crosslinking of trimethylolpropane trimethacrylate for preparation of organic monolithic columns for capillary liquid chromatography. Electrophoresis. 2017 Nov;38(22-23):3029-3035. doi: 10.1002/elps.201700267.

IARC Working Group on the Evaluation of Carcinogenic Risks to Humans. Isobutyl Nitrite, β-Picoline, and Some Acrylates. Lyon (FR): International Agency for Research on Cancer; 2019.

Kulshrestha AS, Gao W, Fu H, Gross RA. Synthesis and characterization of branched polymers from lipase-catalyzed trimethylolpropane copolymerizations. Biomacromolecules. 2007 Jun;8(6):1794-801. doi: 10.1021/bm061096d.

PEG-7 trimethylolpropane is a chemical compound, cleaning agent, emulsifier used in cosmetic products.

Emulsifiers have the property of directly influencing stability, sensory properties and the and surface tension of sunscreens, modulating their filmometric performance.

In industry it is used in the production of polyurethane and polyester foams, plasticizers, synthetic lubricants, alkyd coatings, rosin esters and explosives.  It is multifunctional acrylic monomer and a thermal stabilizing agent of PVC and has resin strengthening properties.

Solubility: it is soluble in water, chloroform and ether, carbon tetrachloride, partially soluble in acetone, while it is insoluble in aromatic hydrocarbon and aliphatic hydrocarbon.

Trimethylolpropane triesters are synthetic biodegradable oil-based lubricants and alternatives to mineral oils, polyalphaolefins and diesters. These oils can be produced from trimethylolpropane (TMP) and fatty acid methyl esters by chemical or enzymatic catalytic synthesis methods. In the present study, a commercial winter-type biodiesel derived from palm oil (ME18) was evaluated as a viable and sustainable source of methyl ester for the synthesis of trimethylolpropane oleic highters (HO-TMPTE). ME18 has a fatty acid profile containing 86.8% oleic acid, 8.7% linoleic acid with the remaining minor concentration of palmitic acid, stearic acid and linolenic acid. Its high oleic property satisfies both good low temperature property and good oxidative stability. The synthetic base oil produced had a viscosity of 44.3 mm(2)/s at 40°C meeting the requirements of ISO 46 oils. It also exhibited an excellent viscosity index of 219 which is higher than other commercial brands of trimethylolpropanotrioleate. Base oil properties such as smoke point, density, acid value, demulsibility and soap content were also examined. The oil was then used and evaluated in terms of its adaptability, stability, and field performance (1).

"Trimethylolpropane studies"

Molecular Formula :C₆H₁₄O₃

Molecular Weight : 134.17

CAS : 77-99-6

UNII  090GDF4HBD

EC Number: 201-074-9

DSSTox Substance ID: DTXSID2026448

MDL number  MFCD00004694

PubChem Substance ID 57653544

NACRES NA.22

Synonyms: 

• 1,1,1-Tris(hydroxymethyl)propane
• 2-Ethyl-2-hydroxymethyl-1,3-propanediol
• Hexaglycerine
• NSC 3576

References____________________________________________________

(1) Chang TS, Yunus R, Rashid U, Choong TS, Awang Biak DR, Syam AM. Palm oil derived trimethylolpropane triesters synthetic lubricants and usage in industrial metalworking fluid. J Oleo Sci. 2015;64(2):143-51. doi: 10.5650/jos.ess14162.

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And a premise on PEG.

Since the PEG (1) family is numerous and is found in many cosmetic, cleaning and medicinal products and others, we need a cognitive premise on the subject that is rather complex from the point of view of safety because these products not only come into contact with the skin but, as in the case of medicine, they are also ingested.

PEG or polyethylene glycols polymerise the condensed ethylene oxide and water and are called polyethylene glycols, but in reality, they are complex chemical components, polymers bound together. For example,  plastic is polyethylene and has a hard consistency, while  polyethylene aggregated to the glycol forms a liquid.

The number that appears after the initials PEG represents the molecular weight and the higher this number is, the less it penetrates  the skin. 

Here below are some studies in Medicine that refer to the use of PEG Polyethylene glycol in various fields.

Intestine

Polyethylene glycol with or without electrolytes is effective for the treatment of functional constipation, both in adults and in paediatric patients, with great safety and tolerability. These preparations are the most effective osmotic laxatives (more than lactulose) and are the first-line treatment for functional constipation in the short- and long-term. They are as effective as enemas in faecalomas, avoid the need for hospitalisation and are well tolerated by patients (especially when given without electrolytes) (2).

In the preparation  for colonoscopy,  polyethylene glycol tablets confirmed efficacy, acceptability, tolerance and safety similar to those of sodium phosphate (3).

For peripheral nerve repair (4).

Eyes

Dry eye syndrome is a disorder that affects 5-34% of the world's adult population with reduced quality of life. Artificial or lubricating tears are the most used therapy for treating this condition due to their low side effects profile, which attempt to modify the properties of the tear film. Polyethylene glycol has demonstrated clinical efficacy in the treatment of this condition (5).

Brain

Polyethylene glycol facilitates the neuroprotective effects of magnesium in head injuries (6).

Tumors

For transarterial chemoembolization, Polyethylene glycol is effective and safe for the treatment of liver cancer, as indicated by good tolerability, quality of life and high tumour response (7). 

Cosmetics

Many types of PEG are hydrophilic and are used as creams, topical dermatological preparations and in cosmetic products such as surfactants, emulsifiers, detergents, humectants and skin conditioners.

Safety varies from type to type given the structural complexity (8).

References___________________________________________________________________

(1) Fruijtier-Pölloth C. Safety assessment on polyethylene glycols (PEGs) and their derivatives as used in cosmetic products. Toxicology. 2005 Oct 15;214(1-2):1-38. doi: 10.1016/j.tox.2005.06.001.

(2) Mínguez M, López Higueras A, Júdez J. Use of polyethylene glycol in functional constipation and fecal impaction. Rev Esp Enferm Dig. 2016 Dec;108(12):790-806. doi: 10.17235/reed.2016.4571/2016.

Santos-Jasso KA, Arredondo-García JL, Maza-Vallejos J, Lezama-Del Valle P. Effectiveness of senna vs polyethylene glycol as laxative therapy in children with constipation related to anorectal malformation. J Pediatr Surg. 2017 Jan;52(1):84-88. doi: 10.1016/j.jpedsurg.2016.10.021.

(3) Chaussade S, Schmöcker C, Toulemonde P, Muñoz-Navas M, O'Mahony V, Henri F. Phosphate tablets or polyethylene glycol for preparation to colonoscopy? A multicentre non-inferiority randomized controlled trial. Surg Endosc. 2017 May;31(5):2166-2173. doi: 10.1007/s00464-016-5214-1.
Tsunoda T, Sogo T, Iwasawa K, Umetsu S, Oikawa-Kawamoto M, Inui A, Fujisawa T. Feasibility and safety of bowel cleansing using low-volume polyethylene glycol with ascorbic acid before pediatric colonoscopy: A pilot study. Dig Endosc. 2017 Mar;29(2):160-167. doi: 10.1111/den.12756.

(4) Hoffman AN, Bamba R, Pollins AC, Thayer WP. Analysis of polyethylene glycol (PEG) fusion in cultured neuroblastoma cells via flow cytometry: Techniques & optimization. J Clin Neurosci. 2017 Feb;36:125-128. doi: 10.1016/j.jocn.2016.10.032.

(5) Pérez-Balbuena AL, Ochoa-Tabares JC, Belalcazar-Rey S, Urzúa-Salinas C, Saucedo-Rodríguez LR, Velasco-Ramos R, Suárez-Sánchez RG, Rodríguez-Carrizalez AD, Oregón-Miranda AA. Efficacy of a fixed combination of 0.09 % xanthan gum/0.1 % chondroitin sulfate preservative free vs polyethylene glycol/propylene glycol in subjects with dry eye disease: a multicenter randomized controlled trial. BMC Ophthalmol. 2016 Sep 20;16(1):164. doi: 10.1186/s12886-016-0343-9.

Labetoulle M, Messmer EM, Pisella PJ, Ogundele A, Baudouin C. Safety and efficacy of a hydroxypropyl guar/polyethylene glycol/propylene glycol-based lubricant eye-drop in patients with dry eye. Br J Ophthalmol. 2017 Apr;101(4):487-492. doi: 10.1136/bjophthalmol-2016-308608.

(6) Busingye DS, Turner RJ, Vink R. Combined Magnesium/Polyethylene Glycol Facilitates the Neuroprotective Effects of Magnesium in Traumatic Brain Injury at a Reduced Magnesium Dose. CNS Neurosci Ther. 2016 Oct;22(10):854-9. doi: 10.1111/cns.12591.

(7) Aliberti C, Carandina R, Sarti D, Mulazzani L, Catalano V, Felicioli A, Coschiera P, Fiorentini G. Hepatic Arterial Infusion of Polyethylene Glycol Drug-eluting Beads for Primary and Metastatic Liver Cancer Therapy. Anticancer Res. 2016 Jul;36(7):3515-21.

(8) Jang HJ, Shin CY, Kim KB. Safety Evaluation of Polyethylene Glycol (PEG) Compounds for Cosmetic Use. Toxicol Res. 2015 Jun;31(2):105-36. doi: 10.5487/TR.2015.31.2.105.