| The Polyester fiber industry has entered a mature period since the1990s. After that, conventional polyester fibers show fierce competition in the market and lead to decreased economic trend. Furthermore, the impending problem of polyester fiber industry is the short of petroleum resources which is the main raw material of polyester fiber. Therefore, it is necessary to find some new materials and novel technologies to replace petroleum resources polyester, so that the basic guarantee for sustainable development will be provided, that is to say, the Bio-based polyester products is becoming a good choice.In comparison with petroleum based polyester, Bio-based PDT (Poly(dihydricals alcohol terephthalate)) fiber made of bio-based ethylene glycol. Because the bio-based polyols contain other glycol, the other glycol will impact greater on such polyester’s processing and performance. The research related to bio-based polyester is less. That is limited the development and application of such bio-based products. Bio-based PDT fiber made of bio-based ethylene glycol has much better of dyeing property, while the wearing comfortability should be improved.Then the Bio-based PDT was synthesized by direct esterification of Bio-EG(bio-based ethylene glycol)and PTA. The third monomer sorbitol which with polyhydroxy structures, the fourth monomer polyethylene glycol (PEG-2000) and the Nano-ZnO was added in the first stage of esterification to improve the hydrophilic and antistatic properties. The modified bio-based polyester fiber was obtained by melt spinning. The main research results and conclusions are listed as follow:Firstly, GC-MS(gas chromatography and mass spectrometry analysis) was adopted to test compositions of different batches biomass polyol in this thesis. Exploring bio-based polyester polymerization process. The structure and thermal property of the bio-based polyester was investigated by the Fourier Transform infrared spectroscopy(FTIR), Thermo Gravimetric Analysis(TGA) and Differential Scanning Calorimetry(DSC). Surface contact angle was used to characterize the hydrophilic properties of Bio-based PDT. It was found that the polymerization process of bio-based polyester need more time to reaction and higher discharge power than that of petroleum based polyester, the adding of modification monomers will induce the decline of bio-based polyester’s intrinsic viscosity. It was found that the melting point Tm of bio-based polyester was5～10℃higher than the petroleum based polyester, and increased with the increasing of the sorbitol. With the adding of nano-ZnO, the melting point of bio-based polyester increased and it reach the maximum of249℃at adding content0.8wt%of the nano-ZnO. The thermal stability of the bio-based copolyester lower than petroleum based polyester, and increased with increasing of sorbitol. In addition, the bio-based polyester has nice water wettability. With the increase of the sorbitol content, the contact angle decreased, which indicated the wettability of bio-based polyester increased.Secondly, the Non-isothermal crystallization kinetics of bio-based polyester was studied with various methods. The Mo equation fitting results showed that it needs greater cooling rate to achieve a certain crystallinity degree for bio-based polyester than petroleum-based polyester, which indicates the bio-based polyester has less crystallization ability than the petroleum-based polyester. The results showed that the adding of sorbitol, PEG and nano-ZnO led to low crystallization ability of bio-based polyester. Similar results were obtained from the crystallization ability of Gc derived by the Ziabicki theory.Thirdly, the hydrophilic polyester fibers was prepared by melt spinning. The spinning temperature was280℃and the spinning speed was2800m/min. Comparison the bio-based polyester fiber’s properties by different batches and modified monomer addition. It was found that the based polyester with low intensity generally0.5～1cN/dtex. But its hydrophilicity is higher than petroleum-based polyester. With the increase of the sorbitol content, the modulus of the modified bio-based polyester fiber decreased, which gave the fiber a soft handle. But the breaking strength the modified bio-based polyester fiber decreased, and the boiling water shrinkage rate increased with the increase of sorbitol content. The bio-based polyester has a nice antistatic performance, while the improvement of antistatic performance with the addition of sorbitol is not obvious. Adding the PEG and nano-ZnO showed good effect on improving the antistatic performance of bio-based polyester. |
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