LETTER TO THE EDITOR Comments on the Paper: Kinetics Studies on Oxirane Cleavage of Epoxidized Soybean Oil by Methanol and Characterization of Polyols Yijin Xu Æ Zoran S. Petrovic Received: 18 September 2008 / Revised: 22 September 2008 / Accepted: 22 September 2008 / Published online: 30 October 2008 Ó AOCS 2008 Dear Editor, Recently a paper entitled ‘‘Kinetics Studies on Oxirane Cleavage of Epoxidized Soybean Oil by Methanol and Characterization of Polyols’’ was published in the Journal of American Oil Chemists’ Society (2008) 85:113–117 (DOI 10.1007/s11746-007-1187-5). The authors claimed they had achieved the synthesis of soy polyol from epox- idized soybean oil (ESO) by ring-opening with methanol WITHOUT A CATALYST. The authors also presented the oxirane cleavage kinetics and characterization of soy polyols by DSC and FTIR but no information on the polyol structures was provided. The most important implication claimed in the paper by the authors would lead to the revision of ring-opening mechanisms of oxiranes. Ring-opening of internal oxiranes with methanol and other alcohols is usually catalyzed by protic acids and Lewis acids. No report has been published on the use of methanol as a ring-opener for oxirane without any catalyst at the temperatures the authors used in the paper! We were skeptical about the findings since they con- tradict the well-established facts. We have examined the process by reproducing the experiments presented in the paper. In short, we could not corroborate the findings in the paper and the comments below are criticisms of the pub- lished paper. We would like to point out some inconsistencies in the paper and show our results obtained by repeating the experimental procedures presented in the paper. Inconsistencies in the Paper 1. Page 113, right column, line 7 from bottom: The preparation of polyols from ESO with various reac- tants has been the subject of many studies [8, 9]. Reference 8 cited in this paper has nothing to do with fatty-based polyols. 2. Page 114, left column, line 2: Other advantages of polyurethanes synthesized from soy-based polyols include a higher thermal stability and improved dielectric properties [1, 7]. Reference 7 is about polyols and does not have any relevance to thermal stability and dielectric properties of polyurethanes. 3. Page 114, Materials Section. The ESO utilized by the authors was not well characterized. Acid value, hydroxyl number (OH#) and Iodine value (IV) were missing. The acid value is critical, because the acid residue has a catalytic effect on ring-opening in the presence of methanol, especially those acids used in the epoxidation process. The infrared spectrum of pure ESO in Fig. 4 shows a relatively high concentration of hydroxyl groups at 3,500 cm -1 . 4. Hydrogen peroxide 30% and sulfuric acid 98% were listed in the materials section but nowhere in the paper were they used. They are usually chemicals used in epoxidation but the authors have used a commercially obtained ESO. 5. Page 114, left column, paragraph 3, Methods Section: ‘‘ESO (40.0 g, 0.154 mol) was charged into a four- necked round-bottomed reaction flask equipped with a reflux condenser and was heated to the desired temperature in a constant-temperature water bath. Methanol, was prewarmed to the same temperature and then quickly added to the flask. Samples of the reaction mixture were taken at 30 min intervals during the Y. Xu Á Z. S. Petrovic (&) Kansas Polymer Research Center, Pittsburg State University, 1701 South Broadway, Pittsburg, KS 66762, USA e-mail: zpetrovi@pittstate.edu 123 J Am Oil Chem Soc (2008) 85:1185–1186 DOI 10.1007/s11746-008-1306-y