【摘要】 采用口模拉伸技术成功连续制备了超轻高强聚丙烯/碳酸钙（PP/CaCO₃）复合线材。由于复合引入的CaCO₃,线材在130℃下其热收缩只有4. 5%（而纯PP的为8%）,热尺寸稳定性大幅度提高。利用SEM对线材的亚微观形貌观察发现,沿拉伸方向大量CaCO₃颗粒两旁存在明显线状空穴,PP球晶形变、取向,形成纤维状结构。经DSC进一步分析表明,提高实际拉伸比,线材的结晶更趋完善。这种高取向的微纤结构线材,拉伸强度可达450MPa,而其密度只有纯PP的90%,低至0. 83 g/cm³。更多还原

【Abstract】 The polypropylene（ PP）/calcium carbonate（ CaCO₃） composite wires with ultra-low density and high-strength were successfully and continuously prepared by die-drawing. Due to the composite introduction of CaCO₃,the thermal shrinkage of the prepared wires at 130 ℃ could achieve 4. 5%,which was lower than pure PP wires（ 8%） and the thermal dimensional stability of the wires were greatly improved.Submicroscopic morphology of the composite wires were observed by scanning electron microscope（ SEM）.And the graph showed that there were obvious linear pores around the CaCO₃ particles along the stretching direction,and the PP spheroids were deformed and oriented to form a fibrous structure. Further analysis by differential scanning calorimetry（ DSC） show that the improvement of the actual draw ratio could obtain more perfect crystallization wires. For this kind of microfiber structure wire with high orientation,the tensile strength could achieve 450 MPa and the density could reach 0. 83 g/cm³ which are only 90% of the pure PP wires.更多还原