The copolymer P(AM-DMC), one kind of cationic polyacrylamide, was synthesized by using acrylamide (AM) and methacryloxyethyltrimethyl ammonium chloride (DMC) as monomers with ultraviolet initiation. The copolymer was characterized by Fourier transform infrared spectroscopy. The composition of the copolymer was determined from the chlorine content by silver nitrate titration. The effects of monomer feed ratio and conversion on the composition of copolymer were discussed. Reactivity ratios were determined by the Fineman-Ross, Kelen-Tudos and Yezrielev-Brokhina-Roskin methods, indicating that their positive order calculation results were very different with those of reverse order, when the reactivity ratios were determined by Fineman-Ross. However, their positive order and reverse order calculation results were similar when the reactivity ratios were determined by the Kelen-Tudos and Yezrielev-Brokhina-Roskin methods. Therefore, the reactivity ratios were determined using the average results of the Kelen-Tudos and Yezrielev-Brokhina-Roskin methods. The reactivity ratios of AM and DMC were 2.3398 and 0.2285, respectively. This result showed that the copolymerization of AM and DMC was a non-ideal random copolymerization. Furthermore, the content of AM segments decreased with the increase of AM feed content, but the content of DMC segments increased. Moreover, the sequence length distribution was irregular and narrow, because AM was prone to homopolymerization.
This work investigates the coating of nano- to submicron-sized hollow nickel particles onto Al powders to optimize the thermal and combustion properties of Al-based energetic materials. Different wt% of hollow nickel particles coated onto Al particles was synthesized using an autocatalytic aqueous reduction method. X-ray diffraction results showed distinct crystalline Al and Ni phases indicating that a pure coating process was achieved. Homogeneous coating of hollow nickel particles onto individual Al particles was also reflected from the scanning electron microscope images. All the samples showed significant improvements in terms of their ignition and kinetics of combustion as compared to untreated Al. The most promising candidate produced was the 30wt%Ni–Al sample whereby the %complete combustion of Al exhibited the largest improvement. The hollow Ni-coated Al samples were also found to perform better than their physically mixed Ni–Al powder samples, as there is more intimate contact between the two components to hasten the overall combustion kinetics.
BACKGROUND ……………………………….. 38 4.2 EXPERIMENTAL PROCEDURE…………….… 39 4.3 CHARACTERIZATION OF Fe 2 O 3 NANOTUBES …………………………………………………… 41 4.3.1 Concentration dependant studies-in preparation of various Fe 2 O 3 nanostructures…………… 45 CHAPTER SYNTHESIS AND CHARACTERIZATION OF Al-Fe 2 O 3 SELF ASSEMBLED NANOENERGETICS SYSTEM…... 51 5.1 BACKGROUND……………….………………… 51 5.2 EXPERIMENTAL PROCEDURE……………….. 51 5.3 RESULTS AND DISCUSSION…………………… 53 5.3.1 FTIR analysis of PVP-coated Fe 2 O 3 nanotubes ……………………………………………..……. 53 5.3.2 Aging effects on Al nanoparticles ……….. 56 v 5.3.3 X-ray diffraction pattern of self-assembled nanothermite…………………………………….. 5.3.4Morphological study of self-assembled nanothermite……………………………………. 5.4 CHARACTERIZATION TECHNIQUES………… 5.4.1 Ignition wire test …………………………... 5.4.2 Dynamic pressure measurements ………… CHAPTER 6 MICROSTRUCTURAL EFFECTS IN SELF ASSEMBLED Al-Fe 2 O 3 NANOENERGETICS..………………………………… 6.1 OVERVIEW…………………………………… 6.2 BACKGROUND……….. ………………..…… 6.3 MORPHOLOGICAL EFFECTS OF Fe 2 O 3 OXIDISERS…………………………………….. 6.3.1 Comparison of reaction kinetic performancevariation in Fe 2 O 3 oxidisers morphologies………. 6.3.2 Derivation of activation energy-variation in Fe 2 O 3 oxidisers morphologies …………………..
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