不同改性剂对ABS/CaCO_3复合材料性能的影响

首先采用不同改性剂对超细重质碳酸钙(CaCO_3)进行表面改性,然后作为无机填料填充丙烯腈–丁二烯–苯乙烯塑料(ABS),制备ABS/CaCO_3复合材料,研究了不同改性剂添加量和改性时间对CaCO_3吸油值、接触角和沉降体积的影响,测试了复合材料的力学性能、熔体流动速率(MFR)和热稳定性,并采用扫描电子显微镜观察了CaCO_3粒子在ABS基体中的分散性。结果表明:经不同改性剂表面处理后,CaCO_3的吸油值和沉降体积降低,接触角增大,其中以大分子活性硅烷(JST-3G)改性的CaCO_3的吸油值和沉降体积(60 min)最小,接触角最大,分别为16 m L/(100 g),0.2 m L/g和120°。经过表面改性的CaCO_3显著提高了复合材料的力学性能和加工流动性,改善了CaCO_3粒子在ABS基体中的分散性。采用大分子活性硅烷(JST-3G)改性的CaCO_3制备的复合材料的力学性能和加工流动性最佳,其拉伸强度、弯曲强度、简支梁缺口冲击强度和MFR分别达到了39.2 MPa,71.2 MPa,13.2 k J/m~2和37.6 g/(10 min)。经不同改性剂处理后,CaCO_3粒子在ABS基体中的分散性均有所提高,尤其以大分子活性硅烷(JST-3G)改性的CaCO_3在ABS基体中的分散性最优。

Effects of Different Modifiers on Properties of ABS/CaCO3 Composites

The surfaces of superfine heavy calcium carbonate (CaCO3) powders were firstly treated by different modifiers，then as inorganic fillers were added into acrylonitrile-butadiene-styrene plastic (ABS) to prepare ABS／CaCO3 composites. The effects of different modifier content and modification time on the oil absorption value，sedimentation volume and contact angle of CaCO3 were studied. The mechanical properties，melt flow rate (MFR) and thermal stability of composites were investigated and the dispersion of CaCO3 particles in ABS matrix was observed by scanning electron microscopy. The results show that the surface of CaCO3 particles were treated，the oil absorption value and sedimentation volume of modified CaCO3 particles decrease as well as the contact angle increases. The CaCO3 treated by macromolecules-based active siloxane (JST-3G) exhibites minimum oil absorption value and sedimentation volume (60 min) as well as maximum contact angle，the values are 16 mL／(100 g)，0.2 mL／g and 120°，respectively.The modified CaCO3 is able to enhance the mechanical properties of the composites，increase the processing fluidity and improve the dispersion of modified CaCO3 particles in the ABS matrix. Compared with other modified samples，the composite containing the fillers of CaCO3 treated by macromolecules-based active siloxane (JST-3G) showes better mechanical properties and processing fluidity.The values of tensile strength，flexural strength，charpy notched impact strength and MFR are 39.2 MPa，71.2 MPa，13.2 kJ／m2 and 37.6 g／(10 min)，respectively. The dispersion of CaCO3 particles in ABS matrix is enhanced after surface modification，especially the composite based on CaCO3 treated by macromolecules-based active siloxane (JST-3G) has an better dispersion.