热处理过程中非晶态聚芳酯超分子结构的变化

本文采用TEM、SAXS及DSC等方法研究了经WAXD证明的芳香族聚酯在T_g,附近退火过程中形成的区域结构,在TEM观察中采用了金装饰制样技术,使形态观察更为清晰,在SAXS测量中采用了Kratky准直系统而提高了分辨率,在DSC测量中,从剩余焓(△H)对升温速率作图,求得热力学平衡态时的(△H)_0。结果证明,聚芳酯在T_g以下长时间退火时,可以形成40—60nm的区域结构。

CHANGE IN SUPERMOLECULAR STRUCTURE OF AMORPHOUS AROMATIC POLYESTER DURING ANNEALING AT TEMPERATURE BELOW ITS Tg

Evidences of domain formation in amorphous aromatic polyester (U-polymer) during annealing at temperature below its T, (about 190℃) for 8 to 120 hours were given by TEM, SAXS and DSC studies in this work. The use of golddecoration technique made the morphology of samples more distinct. Kratky small angle X-ray collimation system was adopted to remove most of the parasitic scattering due to slit edges, thus improving the resolution. In order to confirm that it was the fusion of ordered areas in annealed samples that caused the abnormal endothermic peaks on DSC curves, different heating rates were used for DSC measurements. The excess enthalpy (ΔH)0 was obtained by extrapolating the heating rate to zero. From the results obtained by TEM, SAXS and DSC, it was shown that domains with long spacing of 40-60 nm were formed, when the polymer was annealed for a long period of time at 10-15℃ below its T0.