%0 Journal Article
%T Modification of a Phenolic Resin with Epoxy- and Methacrylate-Functionalized Silica Sols to Improve the Ablation Resistance of Their Glass Fiber-Reinforced Composites
%A Yu Hu
%A Wenlong Geng
%A Hong You
%A You Wang
%A Douglas A. Loy
%J Polymers
%D 2014
%I MDPI AG
%R 10.3390/polym6010105
%X Functionalized silica sols were obtained by the hydrolytic condensation of (¦Ã-methacryloxypropyl)trimethoxysilane (MPMS), (¦Ã-glycidyloxypropyl)trimethoxysilane (GPMS) and tetraethoxysilane (TEOS). Three different sols were obtained: MPS (derived from MPMS and TEOS), GPS-MPS (derived from GPMS, MPMS and TEOS), and GPSD (derived from GPMS, TEOS and diglycidyl ether of bisphenol A, DGEBA). These silica sols were mixed with a phenolic resin (PR). Ethylenediamine was used as a hardener for epoxy-functionalized sols and benzoyl peroxide was used as an initiator of the free-radical polymerization of methacrylate-functionalized silica sols. Glass fiber-reinforced composites were obtained from the neat PR and MPS-PR, GPS-MPS-PR and GPSD-PR. The resulting composites were evaluated as ablation resistant materials in an acetylene-oxygen flame. A large increase in the ablation resistance was observed when the PR was modified by the functionalized silica sols. The ablation resistance of the composites decreased as follows: GPSD-PR > MPS-PR > GPS-MPS-PR > PR.
%K ablation
%K glass fiber-reinforced composite
%K phenolic resin (PR)
%K silica sol
%K silsesquioxanes
%K MPMS
%K GPMS
%K TEOS
%K DGEBA
%U http://www.mdpi.com/2073-4360/6/1/105