<P> Responsive polymer composites were developed by incorporating a functional component into a nonpolar amorphous polymer. The response of the polymer composite is the change in color observed upon exposing the composite to different acids. One application could be a device to monitor the diffusion of different acids in different polymers. </p> <p> The research contained within this thesis deals with an investigation of basic properties of polymer composites. This was accomplished, first through the preparation of a composite of phenolphthalein disodium and Linear Low Density Polyethylene (LLDPE), second, by monitoring the decolorizing process and the aspects that affect it. The investigations included the extrusion parameters, types of acid, acid concentration and indicator concentration, and lastly by quantifying the process through the comparison of empricial diffusion coefficients and corresponding diffusion rates. </p> <p> This study has shown that decolorization occurs at a fast pace in the presence of acetic acid and slow in the presence of hydrochloric acid. Further as the indicator concentration increases, the decolorization process becomes slower. Techniques used to monitor the properties were Scanning Electron Microscopy (SEM) micrographs of freeze fractured composites, Differential Scanning Calorimetry (DSC) scans for the starting materials as well as the composites, and photography of the cross-sections of sample composite cylinders. </p> / Thesis / Master of Science (MSc)

Body fluid identification is important in the field of forensic science as it can provide valuable information to an investigation. An accurate method for detecting blood at a crime scene or on evidence is beneficial to an analyst or investigator. A piece of evidence may be any house-hold object or material; therefore, a test must be able to accurately detect blood on a variety of substrates. The most common preliminary testing method for blood is based on the peroxidase-like activity of hemoglobin. Tests such as phenolphthalein (Kastle-Meyer), Ortho-Tolidine (O-Tol), and Luminol utilize this method. The sensitivity of presumptive blood tests was evaluated using a series of diluted bloodstains on six fabrics: fleece, felt, linen, denim, flannel, and terrycloth. In addition to a direct testing method, two indirect methods were tested utilizing a piece of dry filter paper or a moistened cotton swab. The last portion of this study compared commercial field kits to the laboratory-prepared reagents. This study yielded overall sensitivities for Kastle-Meyer, O-Tol, and Luminol of 1:1000, 1:5000, and 1:10000, respectively. The direct testing resulted in a slightly lower sensitivity with fleece versus the other fabrics. Fleece also resulted in slower and weaker reactions compared to thinner fabrics such as denim, linen, and terrycloth. This suggests that highly absorbent fabrics, such as fleece, can have a negative effect on the sensitivity of catalytic color tests such as Kastle-Meyer and O-Tol. The indirect testing methods utilizing a moistened swab or a dry filter paper were less sensitive compared to direct testing methods. The field kits tested in this study mimic the methods of a moistened swab technique, and the results demonstrated that the field kits were about the same sensitivity or less sensitive compared to the indirect testing methods.

The regulations of many food products in the United States have been made and followed very well but unfortunately some products are not put under such rigorous standards as others. This leads to products being sold, that are thought to be healthy, but in reality contain unknown ingredients that may be hazardous to the consumers. With the use of several instrumentations and techniques the detection, characterization and identification of these unknown contaminates can be determined. Both the AZ-100 and the TE2000 inverted microscope were used for visual characterizations, image collection and to help guide the extraction. Direct analyte-probed nanoextraction (DAPNe) technique and nanospray ionization mass spectrometry (NSI-MS) was the technique used for examination and identification of all adulterants. A Raman imaging technique was than introduced and has proven to be a rapid, non-destructive and distinctive way to localize a specific adulterant. By compiling these techniques then applying them to the FDA supplied test samples three major adulterants were detected and identified.