The goal of this thesis is to investigate the by Gainaru et al. [2013] newlydiscovered low frequency mechanical crossover observed in monohydroxy alcoholsby diluting neat 2-ethyl-1-hexanol (2E1H) with squalane. The complexshear modulus is being measured using a PSG transducer, developed by Christensenand Olsen [1995] at Roskilde University, that allows measurements withfrequencies ranging from 10^(-3) - 10^6 Hz.From the assumption that monohydroxy alcohols can be described as shortchainpolymers, a model proposed by Bo Jakobsen based on an addition of theMaxwell and the Rouse model from Gray et al. [1977] is being investigated andcompared to existing mechanical data of 2E1H. The model is fitted to data forthe monohydroxy alcohol 2E1H obtained from Gainaru et al. [2013], indicatingthat monohydroxy alcohols may be described as short-chain polymers.The three investigated properties of the liquids are low frequency crossovers,the broadness of the alpha-peaks, and the low frequency viscosities. It is concludedthat the experimental equipment at NSM Roskilde University needs to be optimizedwith a wider shear modulus and frequency measuring range, to be ableto observe crossovers in solutions of 2E1H and squalane. The broadest alpha-peakis observed for 0.353 mole fraction squalane in 2E1H, indicating a hinderingin the forming of H-bonds at relatively low concentrations of squalane. Anextra contribution to the viscosity is observed for both liquids and intermediatesolutions. By comparing data of solutions of 2E1H and squalane with experimentaldata from the Glass & Time data repository, it is suggested that abroad alpha-peak and an extra viscosity contribution are generic for monohydroxyalcohols and possibly also polymers of low molecular weight. Similar propertiesare observed for liquid squalane, which in addition shows a strong temperaturedependence, comparable to the structurally similar polymer polybutadiene(PB20).
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