The synthesis, processing, and engineering of low heat release, ultra fire-resistant materials present an important challenge in polymer materials chemistry. One approach to this problem involves the use of materials that char upon decomposition rather than evolve flammable gas. Here, the synthesis and characterization of 1,1-dichloro-2,2-bis(4-hydroxyphenyl)ethene (bisphenol C or BPC) and deoxybenzoin containing polymers are described. Poly(aryletherketone)s containing 1,1-dichloro-2,2-bis(4-hydroxyphenyl)ethene (BPC) were synthesized by the cesium fluoride initiated polymerization of 1,1-dichloro-2,2-bis(4-t-butyldimethylsiloxyphenyl)ethane with 4,4′-difluorobenzophenone (BP-F). These polymers exhibit high char yields by thermogravimetric analysis (TGA), and low heat release capacities were measured by pyrolysis combustion flow calorimetry (PCFC). Poly(aryletherketone)s were prepared from BP-F and various ratios of BPC and bisphenol-A (BPA), and their thermal properties were characterized by TGA and PCFC. Fire-resistant bisphenol C and polydimethylsiloxane (PDMS) polyurethanes were prepared through the polycondensation of 1,1-dichloro-2,2-bis(4-isocyanatophenyl)-ethene (BPC-NCO) with BPC and 2000 g/mol hydroxybutyl-terminated PDMS (PDMS-BuOH). These polyurethanes showed increased char yields based on inclusion of BPC-NCO and PDMS-BuOH, and substantially reduced heat release capacities compared to similar polyurethanes prepared with 2,4-tolylene diisocyanate and poly(tetramethyleneoxide). Halogen-free, fire-resistant copolyarylates were prepared by interfacial copolymerization of isophthaloyl chloride and several relative ratios of 4,4 ′-bishydroxydeoxybenzoin and bisphenol A. The fire-resistance of these polyarylates was explored by TGA and PCFC, and char yields of nearly 40% were observed, twice that of bisphenol A polyarylate. Heat release capacities as low as 81 J/g·K were measured by PCFC. Thus, halogenation, often used to effect fire-resistance in materials, is eliminated all together. Hyperbranched polyphenylenes with bromine and boronic acid termination were prepared by Suzuki coupling polymerization. An exceptionally low heat release capacity of 6 J/g·K were measured by PCFC for bromine terminated polymers and char yields were shown to increase as a function of boronic acid termination due to the formation of a glassy network.
| Identifer | oai:union.ndltd.org:UMASS/oai:scholarworks.umass.edu:dissertations-3960 |
| Date | 01 January 2004 |
| Creators | Ellzey, Kenneth A |
| Publisher | ScholarWorks@UMass Amherst |
| Source Sets | University of Massachusetts, Amherst |
| Language | English |
| Detected Language | English |
| Type | text |
| Source | Doctoral Dissertations Available from Proquest |
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