Jeziorska Regina, Szadkowska Agnieszka, Studzinski Maciej
Lukasiewicz Network-Industrial Chemistry Institute, Rydygiera 8, 01-793 Warsaw, Poland.
Materials (Basel). 2022 May 10;15(10):3421. doi: 10.3390/ma15103421.
Poly(2,6-dimethyl-1,4-phenylene oxide)/polyamide 11 (PPO/PA11 80/20) blend filled with neat (SiO) or modified silica having amine functional groups (A-SiO) was melt mixing in a twin-screw extruder. The silica was prepared by the sol-gel process. SEM shows that, with increasing A-SiO content from 1 to 5 wt.%, the morphology of PPO/PA11blend changed from droplet matrix to co-continuous with phase inversion. The phase inversion was also observed for 5 wt.% of neat silica, but the droplet-matrix structure was retained. The overall rheological and mechanical properties improvement of the A-SiO-filled composites in comparison with the unfilled blend and neat silica counterpart was drastic, especially in terms of viscosity and stiffness. A-SiO improved PPO and PA11 miscibility and reduced the crystallinity of PA11, without affecting the T, owing to the compatibilization effect. On the other hand, neat silica slightly increased the crystallinity of PA11 and decreased the crystallization temperature of PA11 and the glass transition temperature of PPO as a result of its plasticization.
将填充有纯二氧化硅（SiO）或具有胺官能团的改性二氧化硅（A-SiO）的聚（2,6-二甲基-1,4-亚苯基氧化物）/聚酰胺11（PPO/PA11 80/20）共混物在双螺杆挤出机中进行熔融共混。二氧化硅通过溶胶-凝胶法制备。扫描电子显微镜（SEM）显示，随着A-SiO含量从1 wt.%增加到5 wt.%，PPO/PA11共混物的形态从液滴-基体结构转变为具有相转变的双连续结构。对于5 wt.%的纯二氧化硅也观察到了相转变，但液滴-基体结构得以保留。与未填充的共混物和纯二氧化硅相比，填充A-SiO的复合材料的整体流变学和力学性能有显著改善，尤其是在粘度和刚度方面。由于增容作用，A-SiO改善了PPO和PA11的相容性并降低了PA11的结晶度，而不影响熔点。另一方面，纯二氧化硅由于其增塑作用，略微增加了PA11的结晶度，并降低了PA11的结晶温度和PPO的玻璃化转变温度。
