School of Chemical Engineering, Anhui University of Science and Technology, Huainan, 232001, China.
Laboratoire de Chimie Physique, Universite de Paris Sud, 91405, Orsay Cedex, France.
Sci Rep. 2022 Mar 1;12(1):3379. doi: 10.1038/s41598-022-07177-5.
To inhibit the agglomeration of nanotitanium dioxide, a poly (vinyl chloride) (PVC) composite film doped with folic acid-modified titanium dioxide was synthesized and characterized using X-ray powder diffraction, X-ray photoelectron spectroscopy and thermogravimetric analysis coupled with Fourier transform infrared spectroscopy. The average grain size of the folic acid-modified titanium dioxide was found to decrease by 1.3 nm, indicating that the cohesiveness of the nanoparticles is decreased. The lowest temperature for 1.0% thermal decomposition of PVC was determined to be 230.0 °C. The decomposition rate at the peak temperature is found to be 39.6% lower than that of a control sample. The stability of the PVC is improved due to a lower number of surface chlorine atoms as well intermolecular attraction. A mechanism for folic acid modification of titanium dioxide-doped PVC is proposed. After doping, the ester groups in the plasticizer show a significant decrease in the vibration peak intensities observed at 1264 cm, 1736 cm and 1106 cm. The doped PVC film suppresses the release of CO, and the strongest vibration peak at 1264 cm is found to be 17.2% lower than that for the blank sample, indicating that doping is beneficial for plasticizer recovery.
为了抑制纳米二氧化钛的团聚，合成并采用 X 射线粉末衍射、X 射线光电子能谱和热重分析-傅里叶变换红外光谱联用技术对掺杂叶酸修饰二氧化钛的聚氯乙烯（PVC）复合膜进行了表征。发现叶酸修饰二氧化钛的平均晶粒尺寸减小了 1.3nm，表明纳米颗粒的内聚性降低。确定了掺杂 1.0% PVC 的最低热分解温度为 230.0°C。在峰值温度下的分解速率比对照样品低 39.6%。由于表面氯原子数量减少以及分子间吸引力，提高了 PVC 的稳定性。提出了叶酸修饰二氧化钛掺杂 PVC 的机理。掺杂后，增塑剂中酯基在 1264cm、1736cm 和 1106cm 处观察到的振动峰强度显著降低。掺杂的 PVC 膜抑制了 CO 的释放，在 1264cm 处的最强振动峰比空白样品低 17.2%，表明掺杂有利于增塑剂的回收。
