Synthesis, Characterization, and Thermo Mechanical Properties of Siloxane-Modified Epoxy-Based Nano Composite

摘要

In this study, polymer hybrid composites were synthesized by sol-gel process. 3-Amino-propyltrimethoxysilane APTMS)/ c-Glycidoxypropyl trimethoxy-silane (GPTMS); (4, 40-Methylene-dianiline (DDM) and 1,4-Bis(trimethoxysilylethyl) benzene (BTB) were added to DGEBA type epoxy resin for anticipated to exhibit excellent thermal stability. Boron trifluoride monoethylamine (BF_3MEA) was used as catalyst. The structure of nanocomposites was characterized by attenuated total reflectance (ATR) and solidstate ~(29)Si NMR which suggest EP-APTMS-BTB/EP-GPTMS-BTB possesses T~3; T~1-T~0, and T~1 structures when the BTB content was lower than 10 wt and higher 20 wt , respectively. BF_3MEA was proved to be an effective catalyst for the sol-gel reaction of APTMS, but it could not promote for GPTMS. From TEM microphotographs, EP-APTMS-BTB (10 wt ) possesses a dense inorganic structure (particle size around 5-15 nm) compare with the loose inorganic structure of EP-GPTM-/BTB (10 wt ). DSC, TGA were use to analyze the thermal properties of the nanocomposites and DMA was used to analyze the dynamic mechanical properties of hybrid composites. The T_gs of all nanocomposites decreased with the increasing BTB content. A system with BTB content lower than 10 wt showed good dynamic mechanical property and thermal stability (Td_5 increased from 336°C to 371°C, char yield increased from 27.4 to 30.2). The structure of inorganic network affects the Td_5 and dynamic mechanical properties of composite. VC 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40984.