Glatzhofer, Daniel T.,Dinges, Warren Lewis.2013-08-162013-08-161999http://hdl.handle.net/11244/1019A less closely related polymer, poly(p-phenylene sulfoxide) (PPSX) (18) was synthesized by a novel homogenous oxidation of poly(p-phenylene sulfide) 17 with neat fuming nitric acid, fuming nitric acid in trifluoroacetic acid (TFA), and concentrated nitric acid in TFA. Several model compounds and modified reactions were studied which implicated a nitrogen oxide adduct as a major and required element in the selective oxidation to the polysulfoxide rather than the polysulfone. The intrinsic viscosity of the PPSX polymer was determined to be 0.274. PPSX was successfully fractionated yielding a high molecular weight polymer identified by GPC (Mw = 84,000 and Mn = 30,800). Multiple unitary and binary solvent systems were identified for PPSX, and clear, free-standing, flexible films were cast with plasticizer enhancement. Thermal analysis identified PPSX as an amorphous polymer with a decomposition temperature in air of 334° C and in helium of 342° C. The activation energies of the thermal decomposition of PPSX in air and helium were determined by the Friedman method to be 32 +/- 6 and 31 +/- 3 kcal/mol, respectively. PPSX successfully demonstrated the ability to chelate several metals in experiments intended to explore metal extraction applications.A novel polymer derived from these synthetic routes, poly(2,6-dimethyl- p-xylylene) (21), was synthesized and characterized. This amorphous, soluble polymer had the highest molecular weight of any literature reported xylylene polymer measured by GPC (Mw = 150,500 and Mn = 60,5 10). The polymer 21 exhibited excellent thermal stability in helium and air. The onset of thermal decomposition in air (424° C) was more than 100° C higher than all non-fluorinated xylylene polymers. Excellent quality, freestanding, flexible films of 21 were cast from chloroform.With the goal of better understanding previously documented, structurally related, exothermic decompositions of polynitro-paracyclophanes (polynitroPCP), two novel tetramethyl-tetranitro-[2.2]paracyclophanes and their related polymer were synthesized and characterized: 4,8,12,16-tetramethyl-5,7,13,15-tetranitro[2.2]paracyclophane (45) and 4,8,13,15-tetramethyl-5,7,12,16-tetranitro[2.2]paracyclophane (46), and poly(2,6-dimethyl-3, 5-dinitro-p-xylylene) (20). These compounds and previously synthesized dinitro[2.2]PCP's were characterized by DSC thermal analysis techniques. Compounds 45, 46, and 20 decomposed exothermically at 314, 303, and 281° C, respectively. The exothermic decompositions of the polynitroPCP's are not a product of the strain in the dimer [2.2]PCP members of this class, but rather a feature of the ethano bridge system. The elevation of the decomposition temperatures by 33° C in the non-polymer polynitroPCP's is likely due to an attenuation of intermolecular nitro group interactions caused by intramolecular nitro group orientation restrictions. A smaller 10° C decomposition temperature variation in the dinitro[2.2]PCP's follows a similar trend of likely nitro group orientation restrictions. The severely basic and nucleophilic conditions of the Hofmann elimination also proved incompatible to the synthesis of less methylated polynitroPCP's.215 p.Chemistry, Organic.Chemistry, Polymer.Thesis