Effects of Molecular Weight upon Irradiation-Cross-Linked Poly(vinyl alcohol)/Clay Aerogel Properties.
Facile fabrication of mechanically strong poly(vinyl alcohol) (PVOH)/clay aerogel composites through a combination of increasing polymer molecular weights and gamma irradiation-cross-linking is reported herein. The aerogels produced from high polymer molecular weights exhibit significantly increased compressive moduli, similar to the effect of irradiation-induced cross-linking. The required irradiation dose for fabricating strong PVOH composite aerogels with dense microstructure decreased with increasing polymer molecular weight. Neither thermal stability nor flammability was significantly changed by altering the polymer molecular weight or by modest gamma irradiation, but they were highly dependent upon the polymer/clay ratio in the aerogel. Optimization of the mechanical, thermal, and flammability properties of these composite aerogels could therefore be obtained by using relatively low levels of polymer, with very high polymer molecular weight, or lower molecular weight coupled with moderate gamma irradiation. The facile preparation of strong, low flammability aerogels is an alternative to traditional polymer foams in applications where fire safety is important.
Institute of Nuclear Physics and Chemistry, Chinese Academy of Engineering Physics , Mianyang 621000, China.
Hong-Bing
HB
Chen
Institute of Nuclear Physics and Chemistry, Chinese Academy of Engineering Physics , Mianyang 621000, China.
Yan
Y
Zhao
Institute of Nuclear Physics and Chemistry, Chinese Academy of Engineering Physics , Mianyang 621000, China.
Peng
P
Shen
Tianjin Fire Research Institute of the Ministry of Public Security, Tianjin 300381, China.
Jun-Sheng
JS
Wang
Institute of Nuclear Physics and Chemistry, Chinese Academy of Engineering Physics , Mianyang 621000, China.
Wei
W
Huang
Department of Macromolecular Science & Engineering, Case Western Reserve University , Cleveland, Ohio 44106-7202, United States.
David A
DA
Schiraldi
aerogel; gamma irradiation; mechanical properties; molecular weight; poly(vinyl alcohol)