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首页> 外文期刊>Journal of Applied Polymer Science >SYNTHESIS AND CHARACTERIZATION OF BLOCK COPOLYETHERESTERS WITH POLY(TETRAMETHYLENE 2,6-NAPHTHALENEDICARBOXYLATE) SEGMENTS
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SYNTHESIS AND CHARACTERIZATION OF BLOCK COPOLYETHERESTERS WITH POLY(TETRAMETHYLENE 2,6-NAPHTHALENEDICARBOXYLATE) SEGMENTS

机译：聚（对苯二甲酸2,6-萘二甲酸二甲酯）嵌段共聚物的合成及表征

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The block copolyetheresters with hard segments of poly(tetramethylene 2,6-naphthalenedicarboxylate) and soft segments of poly(tetramethylene oxide) were prepared by melt polycondensation of dimethyl 2,6-naphthalenedicarboxylate, 1,4-butanediol, and poly(tetramethylene ether) glycol (PTMEG) with molecular weights of 650, 1000, and 2000. The block copolymers were characterized by Fourier transform infrared and H-1-NMR spectroscopy, differential scanning calorimetry, thermogravimetric analysis (TGA), and X-ray diffraction. The block copolymer compositions were governed by the charge molar ratio (x) of PTMEG to dimethyl 2,6-naphthalenedicarboxylate. It was found that the thermal transitions were dependent on the compositions. As x increases, T-m and Delta H-m of the polyester segments decrease due to the decrease in the sequence length. The X-ray diffraction data also indicate that the crystallinity of the polyester segments decreased as x increased. The molecular weight of the PTMEG used has a significant influence on the glass transition temperature (T-g) and the crystallizability of the polyether segments. The polyether segments of block copolymers derived from PTMEG 2000 could crystallize after cooling and showed a T-g of about -67 degrees C, independent of x. However, the polyether segments of copolymers derived from PTMEG 1000 and PTMEG 650 could not crystallize, and the T-g of the polyether segments decreased as x increased. This is described as the difference in the miscibility between amorphous parts of the polyether segments and those of the polyester segments. The TGA results indicate that the composition had little effect on the nonisothermal thermal degradation under nitrogen. (C) 1997 John Wiley & Sons, Inc. [References: 20]
机译：通过将2,6-萘二甲酸二甲酯，1,4-丁二醇和聚四亚甲基醚熔融缩聚制备具有硬链段的聚（四亚甲基2,6-萘二甲酸四亚甲基酯）和软链段的聚（四亚甲基氧化物）的嵌段共聚醚酯。分子量分别为650、1000和2000的乙二醇（PTMEG）。通过傅里叶变换红外光谱和H-1-NMR光谱，差示扫描量热法，热重分析（TGA）和X射线衍射对嵌段共聚物进行了表征。嵌段共聚物的组成取决于PTMEG与2，6-萘二甲酸二甲酯的电荷摩尔比（x）。发现热转变取决于组成。当x增加时，由于序列长度的减少，聚酯链段的T-m和ΔH-m减小。 X射线衍射数据还表明，随着x的增加，聚酯链段的结晶度降低。所用PTMEG的分子量对玻璃化转变温度（T-g）和聚醚链段的结晶性具有重要影响。衍生自PTMEG 2000的嵌段共聚物的聚醚链段在冷却后会结晶，并显示出约-67℃的T-g，与x无关。但是，衍生自PTMEG 1000和PTMEG 650的共聚物的聚醚链段无法结晶，并且随着x的增加，聚醚链段的T-g降低。这被描述为聚醚链段的无定形部分与聚酯链段的无定形部分之间的混溶性差异。 TGA结果表明该组合物对氮下的非等温热降解影响很小。 （C）1997 John Wiley＆Sons，Inc. [参考：20]

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