Liu Xiliang, Feng Shaomin, Wang Xin, Qi Jin, Lei Dong, Li Yadong, Bai Wei
Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu P.R. China.
University of Chinese Academy of Sciences, Beijing P.R. China.
Turk J Chem. 2020 Oct 26;44(5):1430-1444. doi: 10.3906/kim-2006-55. eCollection 2020.
Polydioxanone (PPDO) is synthesized by ring-opening polymerization of p-dioxanone, using stannous octoate as the catalyst. The polarized optical micrograph (POM) shows thes pherulite growth rate of PPDO decreases with an increase in the isothermal crystallization temperature. PPDO is compression-molded into bars, and PPDO bars are subjected to isothermal annealing at a range of temperatures (Ta = 50, 60, 70, 80, 90, and 100 °C), and correspond to three different annealing times (ta = 1h, 2h, 3h). The effect on PPDO is investigated by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). With an increase in Ta and ta, the grain size and the degree of crystallinity also increase. Meanwhile, the tensile strength is significantly improved. The PPDO bars (90 °C, 2 h) reach the maximum crystallinity (57.21%) and the maximum tensile strength (41.1 MPa). Interestingly, the heat treatment process does not result in serious thermal degradation. It is observed that the hydrolytic degradation of the annealed PPDO is delayed to some extent. Thus, annealed PPDO might have potential applications, particularly in the fields of orthopedic fixation and tissue engineering.
聚对二氧环己酮（PPDO）是由对二氧环己酮开环聚合而成，使用辛酸亚锡作为催化剂。偏光显微镜（POM）显示PPDO的球晶生长速率随等温结晶温度的升高而降低。将PPDO压缩成型为棒材，并在一系列温度（Ta = 50、60、70、80、90和100°C）下对PPDO棒材进行等温退火，对应三种不同的退火时间（ta = 1h、2h、3h）。通过差示扫描量热法（DSC）、热重分析（TGA）、X射线衍射（XRD）和扫描电子显微镜（SEM）研究对PPDO的影响。随着Ta和ta的增加，晶粒尺寸和结晶度也增加。同时，拉伸强度显著提高。PPDO棒材（90°C，2h）达到最大结晶度（57.21%）和最大拉伸强度（41.1MPa）。有趣的是，热处理过程不会导致严重的热降解。观察到退火后的PPDO的水解降解在一定程度上有所延迟。因此，退火后的PPDO可能具有潜在的应用，特别是在骨科固定和组织工程领域。
