| Polyarylene sulfides (PAS) are one kind of the most promising high performance polymers. Various modifications were applied for the polymer structure, including the introduction of appropriate conjugate substituents into the polymer backbone, during which a monomer containing a ring of imides was firstly synthesized and then imide ring was introduced into PAS backbone to get a novel thermoplastic material with improved heat-resistance.Thermal properties are one of the most important properties for polymeric materials. Aromatic polyimides (PI) have not only excellent thermal stability but also good mechanical properties, high chemical resistance and low electric constant; so they are widely used in many ways as semiconductor devices, printed circuitry boards, and so on. The PAAs may be imidized by several methods, such as thermal imidization, chemical imidization with acetic anhydride and triethylamine, and azeotropic dehydration with toluene or chlorobenzene. To fully imidize PAAs thermally, it is necessary to heat them at high temperature (350-400℃). However, during thermal imidization, some side reactions such as dissociation would occur, The published data indicated that only a 50-85% cyclization was achieved in the imidization reaction due to bound solvent residues. As a result, there are some limitations to the application of polyimides in the electronics industry. Among these methods, the chemical imidization of PAAs is a convenient route to polyimides. The mechanism of chemical imidization reation is important features. Therefore, the cyclization process will influence the final structure and properties of PI. There are certain problems connected with the instability of amic acid residual. For overcoming these problems, the monomer was processed firstly in the form of the amic acid and then fully chemical imidization in this paper.A new monomer (Dichlorodiimide) was synthesized by the reaction of 4, 4'– dichloridearylene imide with 4-chlorophthalic anhydride in the presence of acetic anhydride and triethylamine in acetone solvent. Polymerizations of the monomers dichlorodiimide and sodium sulfide were carried out under high temperature (200℃) with N-methyl-2-pyrrolidinone (NMP) as solvent. The method of synthesis monomer and polymer was investigated. The chain and aggregative structure of PASI with the viscosity of 0.24 dl/g was characterized by FT-IR spectrum, H-NMR spectrum, UV-spectrum, wide-angle X-ray diffraction spectrum. Physical properties of the polymer, including thermal stability and solubility, were also studied. DSC and TG analyses revealed the glass transition temperature Tg =101.91℃and that the thermal decomposition temperature Td =405.04℃. The polymer possesses excellent thermal properties and is a novel heat-resistant material.The PASI's hydrochloride (PASIHC) with high Tg(140℃) were synthesized, and its thermal, crystal properties were investigated. The structures of PASIHC were characterized by FT-IR, 1H-NMR and UV. The thermal properties of PASIHC were checked by DSC. It was found that The PASIHC had the performances of optical activity and chiral resolutions ability. It was found that PASIHC had good performance in separating laevorotatory or dextrorotation 3-methyl-1-butanol and 2-methyl-1propanol. The molecular chain of PASIHC presented a long-range order structure in the backbone by the XRD diagram.
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