| Poly(ester-imide-ester)s (PEIE) block copolymer which contains poly(ester-imide) hard segment and polyether soft segment is a kind of thermoplastic elastomers.The properties of this copolymer are influenced by the chemical structure,the block ratio and microphase separation. In this paper, PEIE block copolymer was synthesized by a two-step method. At first, two kind of bisimide dicarboxylic acid monomer were synthesized. Secondly, PEIE block copolymers were polymerized based on a kind bisimide dicarboxylic acid monomer, ethylene glycol and poly(ethylene oxide) diol. The chemical structure of bisimide dicarboxylic acid monomer was characterized. The block copolymer was spun in melt spinning and the properties of copolymers and elastic fibers were discussed. In this article,we got the following results: 1. Two kinds of bisimide dicarboxylic acid monomer were prepared from pyromellitic anhydride and glycine, p-aminobenzoic acid in dimethyl formamide(DMF). Not only the influence of different reactant concentration and mole ratio of monomers to the reactive yield ,but also the influence of reactive temperature to the imidization degree were discussed. 2. The chemical structure of bisimide dicarboxylic acid monomer was characterized by FTIR, 1H NMR and DSC. 3. Three kinds of PEIE block copolymers that the ratio of soft segment and hard segment were 7/3,6/4,5/5 were individually synthesised based on ethylene glycol,poly(ethylene oxide) diol and bisimide dicarboxylic acid monomer by melt polycondensation 4. The melting point of these three kinds of PEIE block copolymers is 232℃,248℃and 260℃respectively because the introduction of high polarity and planarity imide component into PEE copolymers would improve the intermolecular forces between chain segments. The intrinsic viscosity increase with increase of soft segment amount. 5. This PEIE block copolymer can dissolve in pyridine, cellon, m-cresol,partly dissolve in dimethyl formamide, N-Methyl-pyrolidone and water, not dissove in acetone. 6. The moisture absorption test indicates that the moisture absorption ratio decrease with the decrease soft segment amount. 7. The spinnability of the PEIE block copolymer (soft/hard:7/3) was studied by melt-spinning.It showed good spinnability and 230℃would be the proper spinning-temperature. 8. With the increase of spinning speed, the elongation at break of the elastic fiber decreased and the tensile strength of the fiber increased. 9. The PEIE elastic fiber (soft/hard:7/3) has higher elongation at break. After the annealing of fixed-length, the elastic fiber's elastic recovery and elongation at break both decreased, but the tensile strength improved.
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