| Make use of a naphthalene moiety having higher reaction activity and more key company location than a benzene moiety, big symmetrical side groups were introduced to naphthalene on alpha-place , to achieve enhance free volume and reduce molecule polarizability's purpose. Take two 2 , 6- methoxyl naphthalenes as raw material, with benzene formyl chlorine,para-methyl benzene formyl chlorine and meta- methyl benzene formyl chlorine , three kinds containing the naphthalene intermediate monomers were synthesized via a Friedel-Crafts acylation reaction, and composed contain symmetrical characteristic three kinds substituting bisphenols monomers containing a naphthalene via get rid of etherification reaction .Three kinds of monomer structure in NMR spectra (1H NMR) for each hydrogen atom has a very good chemical shift attribution of chemical shift at around 10ppm single peak appears for the-OH hydrogen atom in the chemical shift, and at 3.5 ppm of the original Office-OCH3 peaks disappeared, indicating the reaction at the step, through the deoxidize process of pyridine hydrochloride role-OCH3 into all-OH. At infrared spectroscopy test, the main chemical bond vibration absorption peak can be clearly marked, and at 3200cm-1 occurring at the characteristics of the-OH absorption peak, also shows go etherification success. The use of DSC to determine each compound's melting point, melting range are smaller single peak, and its melting point, respectively: 280℃, 281℃and 295℃.Using typical aromatic nucleophilic substitution reaction route to the top of the bisphenol monomer preparation and activated double-fluoride monomers react to K2CO3 as salt-made reagent, toluene as the water-carrying agent, TMS as the solvent. Reaction system to bring water into salt 1.5-2.0 hours, then the temperature rose to 190-200oC, under the protection of at N2, and then reaction of 4.0-6.0 hours, receive a series of large side group containing symmetry containing naphthalene PAEK.Through nuclear magnetic resonance (1H-NMR) and infrared spectroscopy (FT-IR) of the polymer to be tested for structural analysis, the results confirmed the polymer structure with the expected line. Through the GPC and intrinsic viscosity of characterization to prove that there is a high molecular weight polymer.The use of DSC, for the synthesis of the six polymer thermal properties were studied, six of polymer glass transition temperature at 194℃are more than that of pure PEEK high 50℃. This is because with the symmetry of the naphthalene moiety side group monomer introduction, an increase of molecular rigidity, and also to some extent, restricted the movement of molecules, which have higher Tg values. The use of TGA for the thermal stability of polymers was tested, the results show that in the air, which are six polymer has good thermal stability, at 5% weight loss temperature above 430℃. The synthesis of the six polymer crystallization by wide-angle performance of its WXRD tests to demonstrate that the polymers are all amorphous polymers. Synthesized PAEK its solution casting film-forming mechanical properties after testing showed that it has good mechanical strength.Tested under the conditions at 1MHz series polymer dielectric constant, as well as in boiling water for two hours of water absorption. The results show that our synthesized containing side group symmetry containing naphthalene PAEK with more pure PEEK low dielectric constant. But also with the fluorine-containing poly aryl ether ketone compared to its dielectric constant value less the same.Naphthalene because at theα-position on the introduction of a symmetric carbonyl containing the side group, using the strong carbonyl absorption electron effect of the naphthalene moiety plane of the electron cloud control in a certain range, greatly reduces the external electric field it is polarized therefore has a low dielectric constant.In short, the functional group in the form of side groups into the polymer main chain, go to realize the function of the polymer to further reduce the dielectric constant of the polymer, at the same time achieve a non-fluorinated eventually become a promising new material.
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