An antiplasticizer is any chemical that when added, reduces the free volume of a polymer
thereby restricting the polymeric chain motions. This type of additive usually increases the
modulus and strength but can compromise other important properties such as glass transition
temperature and thermal degradation profile.
Oligomeric amide additives, which when mixed with TGDDM and DDS, react to form
strong hydrogen bonds and reduce the free volume in the system, were synthesized. The
nonaromatic additives, especially those that have shorter methylene sequences, had low
solubility in the resin, while the mixed amide oligomer additive have better solubility. The effect
of these additives to enhance mechanical properties was tested by tensile testing and fracture
toughness measurement. Compact tension results indicated that the additives improved the
resins’ resistance to crack propagation. In general, when the additive is shorter and additive
loading is lower, the material performs better. No general conclusion can be arrived at from the
tensile testing due to the variablility of results caused by unavoidable imperfections incurred
during specimen preparation. The cure kinetics of the resin was studied using Differential
Scanning Calorimetry. Dynamic temperature scanning DSC indicated that the cure reaction was
not affected significantly by these additives. However, an increase in activation energy was
observed. TMA experiments on resins with nonaromatic additives indicated that the additives
slightly increased the softening temperature while DMA experiments on resins with mixed amide
oligomers show that the additives slightly increase the glass transition temperature. TGA
experiments on resins with mixed amide oligomers indicated that the additives did not introduce
significant changes in thermal stability. / Thesis (Ph.D.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Chemistry
Identifer | oai:union.ndltd.org:WICHITA/oai:soar.wichita.edu:10057/5355 |
Date | 05 1900 |
Creators | De los Reyes, Janet |
Contributors | Eichhorn, David M., Stevenson, William T.K. |
Publisher | Wichita State University |
Source Sets | Wichita State University |
Language | en_US |
Detected Language | English |
Type | Dissertation |
Format | xiv, 192 p. |
Rights | Copyright Janet de los Reyes, 2012. All rights reserved |
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