The Synthesis Of Aromatic Ether Ketone Structure Contained Bismaleimide And The Research Of Its Properties

Bismaleimide(BMI) resins have evolved as an important matrixfor polymer composites because of their "epoxy-like" processingcharacteristics and superior thermal stability and fatigue resistance athigh humidity. BMI resins have the same disadvantage as epoxy resins, thatBMI resins are brittle for their high cross-linking structures. Thereforeto enhance the toughness of BMI resins without the reducing of theirthermal ability is important to extend the applied area of BMI. As we know, the brittleness of the BMI resin is due to the shortbackbone between the two maleimide. Extending the length of BMI isa good method to solve the question. The chain-extending bismaleimides that contain aromatic etherketone have particular merits. The existence of the –O- improves thetoughness of the bismaleimides. The aromatic structures maintain thethermal abilities of the bismaleimides. We have synthesized a novel bismaleimides BMPPKBP Weintroduced aromatic ether ketone structure into the bismalei -mides toenhance its toughness without reducing its thermal ability BMPPKBPcontains four methyls, which are expected to improved the solubilityof the bismaleimides We have characterized the structure of BMPPKBP. The analysesof FTIR,MASS,1H-NMR and DSC were given. In the FTIR spectrait can be seen that the absorptions of the hydrogens of the benzene areat 3003.06 cm-1,the absorptions of the methyls are at 2921.77cm-1, the 70吉林大学硕士论文absorptions of the benzene bones are at 837.00cm-1 and 865.92cm-1,the absorptions of the C-O-C are at 1236.21c, the absorptions of thecarbonyl are at 1654.71cm-1. In the FTIR spectra the absorptions of the–NH2(3361.48cm-1) have disappeared, the absorptions of maleimidesare found at 3475.27cm-1 and 1718.35cm-1 BMPPKBP has good solubility. It can dissolve in some kinds ofcommon used solvent, such as ketone and chloroform. BMPPKBP was cured with DDS and DBA. The cure reactionsand the thermal abilities of the cured productions were studied. Thereactions between BMPPKBP and DBA are very complex, thereactions and the structures of resulting networks depend on thestoichiometry of the oligomers. The curing reaction betweenBMPPKBP and DBA has two distinct exotherms. The first one is theresult of ene reaction and Alder-Diels reaction. The next one is due tothe crosslinking of allyls. The Kissinger`s method and Ozawas`s methodwere applicable to the curing reactions. The activation energies were calculated.The activation energy of the reaction between the BMPPKBP and DDS(1:1)is 178.8kj/mol(calculated by Kissinger`s method). In the reactionsbetween BMPPKBP and DBA, the activation energy of the ene reactionand Alder-Diels reaction is 91.25kj/mol(calculated by Kissinger`smethod), and the activation energy of the crosslinking of allyls is161.9kj/mol(calculated by Kissinger`s method). In those reactions theene reaction and Alder-Diels reaction have the highest activation. Theactivation of allyls-crosslinking is verge on that of the reactions betweenBMPPKBP and DBA. The cured productions of BMPPKBP/DDS and 71吉林大学硕士论文BMPPKBP/DBA are both maintain the excellent thermal abilities ofBMI. The thermal ability of the cured production of theBMPPKBP/DDS is relating to the stoichiometry of the oligomers.Because the excessive BMPPKBP can react with the second amine anditself, if the content of the BMPPKBP is increased, the Tg of theproduction will elevate. The thermal ability of the cured production ofthe BMPPKBP/DBA is relating to the stoichiometry of the oligomers.The increasing of the content of DBA can debase crosslinking of thecured production, which can result in reducing of the thermal ability.The Tgs of the production of BMPPKBP/DBA are lower than theproduction of BMPPKBP/DDS with the similar stoichiometry. It's dueto the introducing of aliphatic backbone by the...