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用小角/广角X射线散射(SAXS/WAXS)联用的实验方法考察了等温结晶温度(Tc)和等温时间对聚(ε-己内酯)(PCL)片晶形态的影响.根据WAXS数据计算了PCL的重量结晶度,进而求得其体积结晶度Vc(WAXS).在不同Tc下结晶的PCL样品的Vc(WAXS)均略高于50%.对SAXS谱线做一维相关函数(1DCF)分析,得到了PCL的片晶长周期(LP)和无定形层厚度(La).通过比较WAXS及SAXS的数据分析结果,认为PCL晶体需用“三相模型”予以描述,其过渡层厚度(E)约为LP的15%～18%,对片晶形态具有重要影响.随着Tc升高,PCL晶体的Lc、La及E均逐渐增大,但Lc的变化率最大,这使得结晶度上升.在50℃等温结晶不同时间,发现Lc随延长时间显著增加,而La及E则不断减小.等温10天后,PCL晶体的SAXS谱线上可观察到5级散射,表明片晶相当完善.
The effects of isothermal crystallization temperature (Tc) and isothermal time on the morphology of poly (ε-caprolactone) (PCL) lamellae were investigated by means of small angle / wide angle X-ray scattering (SAXS / WAXS) (WAXS) of PCL samples crystallized at different Tc were slightly higher than 50% .A one-dimensional correlation function of SAXS spectra (1DCF (LP) and amorphous layer thickness (La) of PCL were obtained.Comparing the results of WAXS and SAXS data analysis, it is considered that the PCL crystal should be described by the “three-phase model” The layer thickness (E) is about 15% ~ 18% of LP, which has an important effect on the morphology of the lamella.With the increase of Tc, the Lc, La and E of the PCL crystal increase gradually, but the change rate of Lc is the largest Which leads to the increase of crystallinity.It is found that the Lc increases with the extension of time and the decrease of La and E at different time of isothermal crystallization at 50 ℃ .At 10 days after isothermal, the SAXS spectrum of PCL crystal can be observed with 5-order scattering, Crystal is quite perfect.