【摘 要】
:
Two aromatic polyimides were prepared by twostep way.Firstly,the poly (amic acid) s were synthesized from 1,3-bis(4-amiaophenoxy)benzene and two difierent aroma
【机 构】
:
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,College of Chemistry
论文部分内容阅读
Two aromatic polyimides were prepared by twostep way.Firstly,the poly (amic acid) s were synthesized from 1,3-bis(4-amiaophenoxy)benzene and two difierent aromatic dianhydrides.Secondly,polyimides were prepared via thermal imidization of poly(amic acid) precursors.The polyimides prepared were insoluble in cammon organic solvents such as tetrahydrofuran,chloroform and N,Ndimethylformamide.The inherent viscosities of poly(amic acid)s were 1.82 dL/g and 2.67 dL/g.The high inherent viscosities were due to the strong intra-or intermoleeular hydrogen interaction.The polyimides were characterized by mechanical and thermal analysis.It was found that the samples are of excellent thermal stability,higher glasstransition temperature and excellent dynamic mechanical andthermal properties.
其他文献
The hepatoprotective potential of earthworm extract (EE) (Lampito mauritii, Kinberg) was evaluated against paracetamol-induced liver injury in Wistar albino rat
The electromagnetic mass damper (EMD) control system, as an innovative active control system to reducestructural vibration, offers many advantages over traditio
Objective:To observe the clinical effect of Dihuang Zhixue Capsule(地黄止血胶囊,DZC,a Chinese preparation for cooling blood and dispelling toxic substances) in
In this study, Raman scattering measurements were obtained for momo corals covering their typical range of colors. Three different excitation wavelengths (785,
The tensile cable-strut structure is a self-equilibrate pre-stressed system. The initial pre-stress calculation is the fundamental structural analysis. A new nu
To improve the measurement accuracy of structured laser for inner surface dimensions of a deep hole, a new method to extract the laser stripe center line is pro
A novel tuned liquid damper (TLD) rectangular tank with two angle-adjustable baffles was presented. The numerical analysis was performed using the commercial co
Commwarrior worm is capable of spreading through both Bluetooth and multimedia messaging service (MMS) in smart phone networks. According to the propagation cha
In order to analyze the function demand of the distributed manufacturing information system as well as its control demand,and eliminate information ambiguity am
Because of the effect of unbalance excitation and nonlinear magnetic force, the large vibration of the rotor supported by active magnetic bearing(AMB) will go b