Synthesis And Properties Of Phenolic Containing Carborane

Phenolic resins have excellent adhesion, heat resistance, ablation resistance and flame resistance, which widely used in coatings, adhesives, flame-retardant electronic components, aerospace and other fields. But ordinary phenolic resin is only used below 200? for a long time, and it is difficult to meet the current aerospace demand for high-temperature resistant, so in order to improve the performance of high-temperature for phenolic resin, a variety of domestic and foreign scholars introduced high-temperature resistant group (such as naphthalene ring or fluorene ring) into the phenolic resin structure. Because of carborane for its cage structure and super aromatic electronic structure, the adjacent key is shortened and it can act as "energy tank" at high temperatures. So recently, many scholars use it in a variety of polymers and it is desirable to improve the high temperature properties of the polymer.This paper used carborane disphenol to synthesize a variety of phenolic resin containing carborane to study its structure and high temperature performance, the following key elements:(1) We used o-carborane disphenol (m-carborane disphenol),37% aqueous formaldehyde solution as raw material under the action of acidic catalysts(HCl, Oxalic acid and PTSA) to synthesize a novolac containing carborane. We need to study the difference between the molar ratio of raw materials, the type of catalyst, reaction time and the reaction temperature. These would have influence on the molecular weight and a nitrogen atmosphere char yield 900?. In this way, we can find the best condition of the synthesis of oCNPF and mCNPF is 100?,14h, the catalyst is HCl, and the molar ratio of caborane bisphenol and formaldehyde is 1:4. We analyzed the structure by standard spectroscopy, and the result indicated the successful synthesis of mCNPF and oCNPF. Next the high temperature performance was discussed and the result is the presence of carborane really improved the thermal stability of phenolic.(2) We used the oCNPF (mCNPF) and excess epichlorohydrin under the presence of tetrabutylammonium bromide with sodium hydroxide to obtain the o-CPFE and m-CPFE. The appearance of epoxy group in the infrared spectrum shows the successful synthesis of o-CPFE and m-CPFE. In order to obtain the cure process of o-CPFE and m-CPFE, we used the non-isothermal DSC method by extrapolating and got the cure condition of o-CPFE and m-CPFE with DDS and DDM under isothermal conditions. Finally, we discussed the thermal stability of o-CPFE and m-CPFE by TGA under 900?, and the result is the presence of carborane really improved thermal stability of novolac epoxy.(3) We used the o-carborane disphenol, paraformaldehyde, and hexamethylene diamine (diamino diphenyl methane) to synthesize main chain type benzoxazine containing carborane. We knew the reaction solvent, reaction time and mode of post treatment would affect the yield and the oxazine ring content. In addition, the appearance of oxazine ring in the FTIR spectra indicates the successful synthesis of oCB-hda and oCB-mda. Next, we used the infrared spectra at different temperature to get the cure condition of oCB-hda and oCB-mda. At last, the thermal stability of oCB-hda and oCB-mda were discussed by TGA under 900? and the result is the presence of carborane improved the thermal stability of benzoxazine.