Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale D'Alcontres 31, 98166 Messina, Italy.
School of Molecular Sciences, Arizona State University, Tempe, AZ 85287-1604, USA.
Biochim Biophys Acta Gen Subj. 2017 Jan;1861(1 Pt B):3540-3545. doi: 10.1016/j.bbagen.2016.05.025. Epub 2016 May 20.
Glycerol and sorbitol are glass-forming hydrogen-bonded systems characterized by intriguing properties which make these systems very interesting also from the applications point of view. The goal of this work is to relate the hydrogen-bonded features, relaxation dynamics, glass transition properties and fragility of these systems, in particular to seek insight into their very different liquid fragilities.
The comparison between glycerol and sorbitol is carried out by collecting the elastic incoherent neutron scattering (EINS) intensity as a function of temperature and of the instrumental energy resolution.
Intensity data vs temperature and resolution are analyzed in terms of thermal restraint and Resolution Elastic Neutron Scattering (RENS) approaches.
The number of OH groups, which are related to the connecting sites, is a significant parameter both in the glass transition and in the dynamical transition. On the other hand, the disordered nature of sorbitol is confirmed by the existence of different relaxation processes.
From the applications point of view, glycerol and sorbitol have remarkable bioprotectant properties which make these systems useful in different technological and industrial fields. Furthermore, polyols are rich in glassforming liquid phenomenology and highly deserving of study in their own right. The comparison of EINS and calorimetric data on glycerol and sorbitol helps provide a connection between structural relaxation, dynamical transition, glass transition, and fragility. The evaluation of the inflection point in the elastic intensity behavior as a function of temperature and instrumental energy resolution provides a confirmation of the validity of the RENS approach. This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo.
甘油和山梨糖醇是具有成玻璃氢键合系统的特性,这些特性使这些系统从应用的角度来看也非常有趣。这项工作的目的是将这些系统的氢键特征、弛豫动力学、玻璃化转变特性和脆性联系起来,特别是寻求对它们非常不同的液体脆性的深入了解。
通过收集弹性非相干中子散射(EINS)强度作为温度和仪器能量分辨率的函数,对甘油和山梨糖醇进行比较。
强度数据与温度和分辨率的关系通过热约束和分辨率弹性中子散射(RENS)方法进行分析。
与连接点有关的 OH 基团的数量,在玻璃化转变和动力学转变中都是一个重要的参数。另一方面,山梨糖醇的无序性质通过不同的弛豫过程得到了证实。
从应用的角度来看,甘油和山梨糖醇具有显著的生物保护特性,使这些系统在不同的技术和工业领域都具有用途。此外,多元醇在玻璃形成的液体现象学方面非常丰富,值得单独研究。甘油和山梨糖醇的 EINS 和量热数据的比较有助于在结构弛豫、动力学转变、玻璃化转变和脆性之间建立联系。评估弹性强度行为随温度和仪器能量分辨率的转折点,提供了对 RENS 方法有效性的确认。本文是题为“科学为生命”的特刊的一部分,客座编辑:奥斯汀·安格尔博士、萨勒诺·马加祖博士和费德里卡·米利亚尔多博士。