基于同步辐射光源X射线散射对聚乙醇酸挤出棒材退火条件的优化

Optimization of Annealing Conditions of Poly(glycolic acid)Extruded Rods Based on X-ray Scattering Through Synchrotron Radiation Light Source

文中用同步辐射光源对聚乙醇酸(PGA)挤出棒材的切片进行广角X射线散射(WAXS)和小角X射线散射(SAXS)表征,研究聚乙醇酸棒材在挤出成型后优选的退火条件,以尽可能消除内应力,改善棒材后续的机械加工性。WAXS结果表明,高温更有利于微观应变的减小,但较高温时晶粒尺寸会随退火时间的延长而减小。SAXS结果表明,高温更有利于取向程度的减小,退火时间对取向程度的影响明显弱于退火温度。综合各数据建立目标函数,并利用响应面分析法进行分析。结果表明,在实验范围内,PGA棒材的优选退火条件为200℃退火2h。

Slices of poly(glycolic acid)(PGA)extruded rods were characterized by wide angle X-ray scattering(WAXS)and small angle X-ray scattering(SAXS)using a synchrotron radiation light source,and the optimal annealing conditions of PGA rods after extrusion were studied to eliminate internal stress and improve the subsequent machinability of the rods.The WAXS results indicate that high temperature is more advantageous to thereductionofmicro-strain,butthecrystalgrain size decreases with increasing annealing time at higher temperatures.The SAXS results indicate that high temperature is more conducive to decreasing the degree of orientation,and the effects of annealing time on the degree of orientation is significantly weaker than that of annealing temperature.The objective functions were established by integrating various data and analyzed through Response Surface Methodology.The results show that the optimal annealing conditions for PGA rods within the range of the experimental conditions studied are annealing at 200℃for 2 h.