| Optical fiber buried in large aircraft composite materials can achieve real-time monitoring of material structure. The temperature of Large aircraft in the molding will reach above 180℃,therefore, the coating of optical fiber should can undertake high temperature so that the optical fiber will not be microbending to impact signal transmission when it is under high temperature and pressure, and will not be aging and embrittlement, and these performance mainly depend on the oligomer of coating. Therefore, research on all aspects of optical fiber coating is very important in the subject of optical fiber embedded in large aircraft.The general optical fiber coating is epoxy acrylate resin, it cannot meet the conditions that be used in high temperature. So this paper would modify epoxy acrylate resin to improve its heat-resistance performance. Firstly, epoxy acrylate resin was modified with vinyltriethoxysilane, dibutyltin dilaurate was used as catalyst, epoxy resin modified with polysiloxane was synthesized successfully. The chemical structure of synthetic product was identified by FT-IR spectra, the best reaction conditions are as follows, reaction temperature is 80℃,time is 8h, the amount of catalyst is 1%,the molar ratio of epoxy acrylate resin and vinyltriethoxysilane is 2:1. Then tested for its curing properties, the results showed that epoxy acrylate modified with polysiloxane possessed good thermal stability performance, its thermal decomposition temperature is 465℃,its increased 125℃higher than epoxy acrylate resin, its glass transition temperature is 174℃, increased 110.2℃.The level of adhesion is 3, the coating hardness is 3H.Then the paper studied epoxy acrylate resin modified with nano-SiO2 and nano-OMMT. The effect of illumination time on EA/SiO2 and EA/OMMT was studied, the curing time is 270s, and its curing were characterized by SEM and XRD. With the increasing content of nano-particles, film tensile strength increased firstly and then decreased, pencil hardness gradually increased from 2H to 4H, adhesion increased from level 2 to level 1.Adding nano-Si02 and nano-OMMT could not improved the thermal stability of epoxy acrylate clearly, the former one increased about 10℃,the latter one increased 27℃,glass transition temperation of the former one increased from 63.8℃to 108℃, the latter one increased from 63.8℃to 113.8℃, the thermal expansion coefficient of the system after adding nano-particle decreased gradually, the former decreased in half, the latter one decreased from 1.5×10-4K-1 to 1.2×10-4K-1.
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