A design of experiments methodology was used to investigate the effect of vapor-grown carbon nanofiber (VGCNF) weight fraction, high-shear mixing time, and ultrasonication time on the Izod impact strength of vinyl ester (VE) based nanocomposites. A response surface model (RSM) was developed for predicting impact strengths using a regression analysis approach. The RSM predicts a maximum increase in impact strength of 18% at a VGCNF weight fraction of 0.17 parts per hundred parts resin (phr) (a volume percent of ~0.1) and 100 min high-shear mixing when compared to that of neat VE. The impact strength predictions show an initial increase for low VGCNF weight fractions and extended high-shear mixing. However, a marked decrease in impact strength occurred as the VGCNF weight fraction increased above 0.45 phr. Scanning electron micrographs of the fracture surface of several specimens suggest that the impact strength of VGCNF/VE nanocomposites is directly related to nanofiber dispersion.
|Advisor:||Lacy, Thomas E., Jr., Toghiani, Hossein|
|Commitee:||Dubien, Janice L., Pittman, Charles U., Jr., Sullivan, Rani W.|
|School:||Mississippi State University|
|School Location:||United States -- Mississippi|
|Source:||MAI 50/03M, Masters Abstracts International|
|Subjects:||Aerospace engineering, Nanotechnology, Materials science|
|Keywords:||Mechanical properties, Mechanical testing, Polymer-matrix composites, Statistical properties/methods|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be