| Epoxy resin (EP) is one of the most polular thermoset resins as matrix materials. Itis widely used for great adhesive, flexible processing design, superior mechanicalstrength and low lost. However, cured epoxy resin has poor heat resistance, flameresistance and toughness, which limits its application in some fields. Therefore, thestudy on modify of epoxy resin is a very important.Firstly, the thermal and thermo-cxidative stability, flame resistance and mechanicalproperties of pure EP improved by adding2,2-bis [4-(3,4-dicyanophenoxy) phenyl]propane (BAPh) monomers. The BAPh/EP blends and cured polymers were preparedby melt blending and casting moulding. The melting and curing behavior are studied byDSC and AR, TGA is used for the test of thermal properties, and the flame resistance ischaracterized by oxygen index tester and vertical burning synthesizer. The studies onthe copolymerization of BAPh/EP with the weight ratio are10:90,20:80,30:70,40:60and50:50, and the results showed that the initial decomposing temperature (Ti) of pureEP increased by29.2oC and74.3oC in nitrogen and air respectively when the ratioachieved50:50. LOI value (oxygen index) of50:50BAPh/EP copolymers achieved34.5%which increased by5.0%compared with pure EP. Furthermore, the verticalburning grade of BAPh/EP copolymers improved from no grade to V-0grade.Secondly, according to the results of the reaction properties, the glass fiberreinforced composites were prepared through hot pressing process using BAPh/EPblends as the matrix, glass fiber as the reinforced materials. The studies discussed theprocess of BAPh/EP blends with the weight ratio are10:90,20:80,30:70,40:60and50:50as high-performance matrix composites properties and researched the propertiesof BAPh/EP glass fiber composites. The thermal and mechanical properties of50:50BAPh/EP glass fiber composites are the best. The Tiof50:50BAPh/EP glass fibercomposites increased by5.7oC and8.0oC in comparison with pure EP glass fibercomposites in nitrogen and air respectively. The flexural and tensile strength of50:50BAPh/EP glass fiber composites achieved652.2MPa and332.5MPa, which increasedby96.3MPa and23.1MPa compared with pure EP glass fiber composite, respectively. The quality changes were small of50:50BAPh/EP glass fiber composites after boilingwater, and the rate of change was the smallest after soaking in ethanol and toluene thanother BAPh/EP glass fiber composites.At last, polyarylene ether nitriles (PEN) was added to50:50BAPh/EP blends andthe research was carried out on the properties of BAPh/EP/PEN blends. The studies onthe copolymerization of PEN with the weight ratio of PEN contents are5wt%,10wt%and15wt%, and the results showed that PEN could increase the curing rate. For thecured BAPh/EP/PEN systems, PEN played a role in toughening and strengthening. Theflexural strength, flexural modulus and flexural strain of BAPh/EP/PEN glass fibercomposites all increased and then decreased. The quality changes were small of10wt%BAPh/EP/PEN glass fiber composites after boiling water, and the rate of change ofBAPh/EP glass fiber composites.were within1.5%after soaking in ethanol and toluene.According to the results of the investigations, the thermal and thermo-cxidativestability and the flame resistance of pure EP improved after adding BAPh. And theBAPh/EP glass fiber composites possessed good mechanical properties, boiling waterresistance and corrosion resistance. In addition, PEN could increase the curing rate andthe toughness without sacrificing the excellent thermal and thermo-oxidative stability. |
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