Engineering Commons^™

Synthesis Of Trimethylpropane-Tolylene-2,4-Diisocyanate Adduct And Its Blocked Monomers, Farhad Forohar

Theses

A trimethylolpropane adduct of tolylene-2,4-diisocyanate (TMP-TDI) was prepared by reaction in a heterogeneous solvent system. The isocyanate functional groups of the TMP-TDI adduct were blocked with the following blocking agents: p-cresol, eugenol, o-chlorophenol, and one to one mole ratio of mixtures of 2-hydroxyethyl methacrylate (HEMA) and each of the three preceding blocking agents. A sample of TMP-TDI adduct blocked with only HEMA was also prepared. The products were characterized by melting point, infrared spectroscopy, and elemental analysis. Monomers of TMP-TDI blocked with 50% HEMA and 50% blocking agents may be very useful as dental restorative materials.

Calibration Of Flame Ionization Detector For Chlorinated Hydrocarbons, Nahid Jabalameli

Theses

Relative Responses and Calibration Factors were developed for several volatile organic (mostly chlorinated) priority pollutant species in order to use one single stable compound (e.g.Benzene) for daily instrument calibration. This would replace the procedure of using a standard mixture of target compounds (25-35). This is of particular advantage because the standard mixture may not have all species stable or may show loss of some components relative to others due to wall adsorption in the standard (compressed gas) stainless steel cylinder.

The use of a single standard species was made possible by developing "accurate" relative response and calibration factors of all …

Three Studies On Airborne Polycyclic Aromatic Hydrocarbons, Carol Sophia Eveleens

Theses

Three studies have been conducted on polycyclic aromatic hydrocarbons found on airborne particulate matter. The first investigation involves the determination of fly ash "activity" in the reaction of two PAHs adsorbed on its surface. Mass spectrometry is used to monitor the exchange of hydrogen and deuterium atoms between anthracene and anthracene-d10. The results indicate that some fly ashes exhibit "activity" in the reactions of PAHs adsorbed on its surface. The second investigation involves the determination of cyclopenta[cd]pyrene (CcdP) and benzo[ghi]flouranthene (BghiF) on samples of airborne particulate material collected from two automobile traffic tunnels. Glass capillary gas chromatography with a precolumn …

Characterization Of Tdi-Hema Homopolymer Prepared Via An Immiscible Solvent System. Synthesis And Investigation Of Oligodichloroketene, Manuel Montero

Theses

The objective of this thesis has been divided in two parts.

The first part is subdivided into two areas. First a "Universal" calibration curve for gel permeation chromatography (GPC) was construc-ted using different molecular weight standards of PMMA and MMA-HEMA co-polymers. By measuring the viscosity of the different molecular weight solutions and calculating the Vr, (retention volume), from GPC data, plots of In [ η ] Mw against Vr and In Mw against Vr are obtained. These curves can be used to obtain the molecular weight of any linear (not crosslinked) copolymer by simple measurements of viscosity and GPC data. …