TY - JOUR
T1 - Mechanical and dielectric properties of microcellular polycarbonate foams with unimodal or bimodal cell-size distributions
AU - Ma, Zhonglei
AU - Zhang, Guangcheng
AU - Yang, Quan
AU - Shi, Xuetao
AU - Liu, Yang
N1 - Publisher Copyright:
© The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
PY - 2015/5/6
Y1 - 2015/5/6
N2 - This article reports on the compressive, dynamic mechanical and dielectric properties of microcellular polycarbonate foams with unimodal or bimodal cell-size distributions fabricated using the environment-friendly supercritical carbon dioxide. The effects of cell morphologies such as relative density, cell-size distribution and porosity on the compressive strength, Young's modulus, storage modulus, loss modulus, dielectric constant and loss tangent of the microcellular polycarbonate foams are investigated quantitatively. Experimental values of the compressive strength and Young's modulus fit very well with the theoretical values calculated from the Gibson-Ashby model at low relative densities. The higher relative density leads to higher storage modulus and loss modulus. The bimodal foams significantly improve the compressive and dynamic mechanical properties compared to the unimodal foams with the same relative density. The dielectric properties of microcellular foams depend only on the total porosity, but not on the cell-size distribution or microstructure of the foams. With increasing porosity, the dielectric constant of the microcellular foams gradually decreases, and agrees very well with the curve calculated from the Maxwell-Garnett-spheres model.
AB - This article reports on the compressive, dynamic mechanical and dielectric properties of microcellular polycarbonate foams with unimodal or bimodal cell-size distributions fabricated using the environment-friendly supercritical carbon dioxide. The effects of cell morphologies such as relative density, cell-size distribution and porosity on the compressive strength, Young's modulus, storage modulus, loss modulus, dielectric constant and loss tangent of the microcellular polycarbonate foams are investigated quantitatively. Experimental values of the compressive strength and Young's modulus fit very well with the theoretical values calculated from the Gibson-Ashby model at low relative densities. The higher relative density leads to higher storage modulus and loss modulus. The bimodal foams significantly improve the compressive and dynamic mechanical properties compared to the unimodal foams with the same relative density. The dielectric properties of microcellular foams depend only on the total porosity, but not on the cell-size distribution or microstructure of the foams. With increasing porosity, the dielectric constant of the microcellular foams gradually decreases, and agrees very well with the curve calculated from the Maxwell-Garnett-spheres model.
KW - Microcellular foams
KW - cell-size distribution
KW - compressive properties
KW - dielectric properties
KW - dynamic mechanical properties
KW - relative density
UR - http://www.scopus.com/inward/record.url?scp=84930421665&partnerID=8YFLogxK
U2 - 10.1177/0021955X14542989
DO - 10.1177/0021955X14542989
M3 - 文章
AN - SCOPUS:84930421665
SN - 0021-955X
VL - 51
SP - 307
EP - 327
JO - Journal of Cellular Plastics
JF - Journal of Cellular Plastics
IS - 3
ER -