Using Pyrene Excimer Fluorescence To Probe the Interactions between Viscosity Index Improvers and Waxes Present in Automotive Oil
A new methodology based on pyrene excimer fluorescence (PEF) was applied to quantitatively measure the actual level of intermolecular association between ethylene–propylene (EP) copolymers in toluene in the presence of wax, an intrinsic component of engine oils. EP copolymers are commonly used as viscosity index improvers (VIIs) in engine oils. Unfortunately, waxes in engine oils thicken the oil and are suspected of associating with VIIs at low temperature. In this study, four EP copolymers were maleated to yield EP-MA and then fluorescently labeled with 1-pyrenemethylamine to yield Py-EP. Successful maleation and pyrene labeling were confirmed by Fourier transform infrared (FTIR) and UV–vis absorption spectroscopy. The solution behavior of the EP copolymers in the presence of wax was characterized by PEF, which was used to quantitatively measure the molar fraction of intermolecular interactions (finter) between EP copolymers in the absence or presence of wax. The fraction finter was determined through th...
Solmaz Pirouz; Jean Duhamel; Sheng Jiang; Akhilesh Duggal
We recently generalized the formerly alignment-dependent multivariate image analysis applied to quantitative structure–activity relationships (MIA-QSAR) method through the application of the discrete Fourier transform (DFT), allowing for its application to noncongruent and structurally dive ... more
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Rohm and Haas Powder Coatings is delighted to announce that its Reading, Pennsylvania, facility is the first site in the world to receive the RCMS® Site Certification awarded by the American Chemical Council (ACC).
When Raj Gupta, Chairman and CEO of Rohm and Haas Company, became Chairman ... more