Session: 01-08-01: Passive, Semi-Active, and Active Noise and Vibration Control

Paper Number: 145125

145125 - Vibrational Response of Boron Nitride Nanofiller in Epoxy Nanocomposites: An Experimental Study 

The vibrational response of an amorphous thermoplastic polymer is evaluated as a function of a mixture of boron nitride nanotubes and hexagonal boron nitride (BNNT/h-BN) concentration and aging. This study considers neat resin and resin with BNNT/h-BN of concentrations varying from <1% BNNT and <2% h-BN wt.%. BNNT was selected because of its many capabilities, including radiation resistance, thermal degradation resistance, and strength, and for the limited research on its macroscopic dampening properties. h-BN was selected as a nanofiller due to its hydrophilic properties and capability to work as a secondary relaxation agent.  Cantilever beam specimens were made and excited consistent with ASTM E756-05. Vacuum degassing was applied to the sample mix before molding in an autoclave to ensure the least number of voids. To test the samples, an automated electromagnetic shaker induces excitation frequencies from 100 Hz to 500 Hz using a sine frequency input from a waveform generator to evaluate the samples. Contactless laser position sensors are used to obtain the sample's excitation. The result of the analysis obtains the output over input in the form of compliance. MATLAB is then used to analyze the raw position data and obtain the locations and general shape of the resonant modes. Once the modes are obtained, material properties such as the loss factor and Young’s modulus are acquired.  Lastly, samples were evaluated under the microscope to verify the concentration of constrained region and void content resulting from the addition of the nanofiller.  The analysis concluded that the resonant frequency reduced substantially with the introduction of nanofiller, indicating that adding BNNT helps constrain the polymer’s mobility. The data presented an increase in loss factor with the increase of mode number for all samples. The Young’s modulus exhibited a reduction in rigidity depending on the concentration of BNNT and h-BN compared to neat resin. During aging tests, the resonant frequencies did not change much except in the second mode for the neat resin, related to possible micro-cracks forming in the sample. The loss factor increases overall with sample aging. For the third mode, all samples experience reduction in resonant frequency and Young’s modulus; however, nanofiller samples exhibited a retarded effect providing evidence that the nanofiller is helping preserve the material against wear and tear. The loss factor for the third mode increases but at lesser extent compared to the second mode. Overall, once nanofillers are added to the matrices their properties are deteriorated in the presence of bubbles and the resulting  lack of interconnected constrained regions. The bubbles decreased substantially with the addition of h-BN, which offers hydrophilic properties and can work as secondary relaxation elements to the BNNTs, thus enhancing dampening properties and improving Young’s modulus. These interactions were further enhanced with aging, increasing loss factor, and Young’s modulus on samples with sufficient h-BN to dissuade bubble formation. In some cases, all samples experienced signs of wear damage from a second round of tests after aging. Still, the nanofiller samples showed slower signs of degradation, providing evidence of the nanofiller's capacity to preserve the sample.

Presenting Author: Luis Rafael Miranda Rodriguez Rutgers, The State University of New Jersey

Presenting Author Biography: Luis Rafael Miranda Rodriguez graduated Summa Cum Laude, top of his class, with his bachelor's in mechanical engineering at Universidad Ana G Mendez Gurabo Campus's Engineering Department in 2019 and entered the Ph.D. program for the mechanical and aerospace engineering department at Rutgers University in New Brunswick. His undergraduate research focused on creating a device for simulating wave generation. His graduate research focuses on evaluating polymer matrix composites, including Polyamides infused with glass fiber, Epoxy with Boron Nitride Nanotubes, and hexagonal boron nitride and polyethylene terephthalate with in-situ exfoliated graphene.

Authors:

Luis Rafael Miranda Rodriguez Rutgers, The State University of New Jersey
Shalaka Tendolkar Rutgers, The State University of New Jersey
Kyra Wilson, Rutgers, The State University of New Jersey
Crystal Yung, Rutgers, The State University of New Jersey
Spiro Klimentos Rutgers, The State University of New Jersey
Andrew Norris, Rutgers, The State University of New Jersey
Jonathan P. Singer Rutgers, The State University of New Jersey
Assimina A. Pelegri Rutgers, The State University of New Jersey