Abstract: In this work poly-m-chloroaniline(PmClAn) was synthesized by emulsion polymerization. By discussing the influences of reaction temperature and concentrations of initiator on the polymerization reaction, it was found that PmClAn with mean molecular weight of 1.85×10³(corresponding to 15 chain elements) could be obtained under the following conditions: 80 ℃, [M]=0.187 mol/L, [SDS]=4.8×10^-2mol/L, [KPS]=5.6×10^-2 mol/L(where M, SDS and KPS stand for monomer, emulsifier and initiator K₂S₂O₈, respectively), reaction period 2.5 h. From ¹H NMR, FTIR, TEM and SEM measurements the structure of PmClAn was determined. It was found that in the macromolecular chain the ratio of benzoid to quinoid units was 3:2, and that PmClAn was characterized by its typical molecular crystalline being monoclinic with crystall-cell parameters of a=0.679 nm, b=2.304 nm, c=0.5734 nm, α=90°, β=100.9° and γ=90°. By using MM+ molecular mechanics methode in Hyper Chem program, X-ray diffraction data were analyzed, thereby the configuration of PmClAn chain was determined and optimized.

Key words: Poly-m-chloroaniline, Emulsion polymerization, Molecular structure