【作者】 童佳佳；

【导师】 杨保俊；

【作者基本信息】 合肥工业大学 ， 化学工程与技术， 2021， 硕士

【摘要】 针对未改性纳米CaCO₃在塑料应用过程中易团聚,分散性、相容性较差等不足,依据GB/T19590-2011中橡胶塑料用纳米CaCO₃推荐指标要求,采用脂肪酸类改性剂,对实验室自制纳米CaCO₃进行表面改性,并考察其在ABS、PP塑料中的添加效果。所开展的主要研究工作及结论如下:（1）筛选并确定DL-苹果酸为较适宜的改性剂,考察并确定较适宜的改性工艺条件为:DL-苹果酸用量1.5%、反应温度60℃、固液比8︰100、反应时间120min、搅拌速率300 rpm。改性后纳米CaCO₃样品的吸油值为26.14 g·100g^-1,且其它各项指标均达到或优于GB/T19590-2011中橡胶塑料用纳米CaCO₃的技术指标要求。（2）考察了改性纳米CaCO₃的添加对ABS复合材料的力学性能的影响。结果表明:较适宜的改性纳米CaCO₃添加量为10%,此时,改性纳米CaCO₃/ABS复合材料的冲击强度、断裂伸长率、拉伸强度、弯曲强度分别提升了21.8%、30.28%、5%、2.7%;并对改性纳米CaCO₃的作用机制进行了初步探讨。（3）考察了改性纳米CaCO₃的添加对PP复合材料的力学性能的影响。结果表明:改性纳米CaCO₃最大填充比例可达10%,此时,改性纳米CaCO₃/PP复合材料的冲击强度、弯曲强度分别提升了16.2%、19.85%;而断裂伸长率、拉伸强度分别只降低了9.4%、5.89%;并对改性纳米CaCO₃的作用机制进行了初步探讨。（4）改性纳米CaCO₃/ABS、改性纳米CaCO₃/PP复合材料热稳定性分析结果显示:改性纳米CaCO₃具有抑制改性纳米CaCO₃/ABS、改性纳米CaCO₃/PP复合材料降解,提高其热稳定性的作用。（5）改性纳米CaCO₃/ABS、改性纳米CaCO₃/PP复合材料熔体质量流动速率分析结果显示:当改性纳米CaCO₃添加量较小时,改性纳米CaCO₃的添加,能够提高改性纳米CaCO₃/ABS复合材料（改性纳米CaCO₃添加量<18%）、改性纳米CaCO₃/PP复合材料（改性纳米CaCO₃添加量<10%）的熔体质量流动速率,改善其加工性能。更多还原

【Abstract】 In view of the shortcomings of the unmodified nano-CaCO₃ in the application of plastics,such as easy agglomeration,poor dispersion and inferior compatibility,according to the recommended technical requirements of nano-CaCO₃ for rubber and plastics in GB/T 19590-2011,the surface modification of nano-CaCO₃,which was the self-made product of our laboratory,was carried out using fatty acid as modifier,and then the addition effect of modified nano-CaCO₃ on ABS and PP plastics was investigated.The main research work and conclusions are as follows:（1）DL-malic acid was screened as the more suitable modifier.The optimum modification conditions were determined as follows:DL-malic acid dosage 1.5%,modification temperature 60℃,the ratio of solid to liquid 8:100,modification time120 min and stirring rate 300 rpm.The oil absorption value of the modified nano-CaCO₃ sample is 26.14 g·100g^-1,and all the other indexes meet or exceed the requirements of nano-CaCO₃ for rubber and plastics in GB/T19590-2011.（2）The addition effect of modified nano-CaCO₃ on the mechanical properties of ABS composites was investigated.The experimental results showed that when adding10%of modified nano-CaCO₃,the impact strength,elongation at break,tensile strength and bending strength of the modified nano-CaCO₃/ABS composites increased by 21.8%,30.28%,5%and 2.7%respectively,compared to that of pure ABS.The action mechanism of modified nano-CaCO₃ was preliminarily discussed as well.（3）The addition effect of modified nano-CaCO₃ on the mechanical properties of PP composites was investigated.The experimental results showed that when adding 10%of modified nano-CaCO₃,the impact strength and bending strength of the modified nano-CaCO₃/PP composites increased by 16.2%and 19.85%,compared to that of pure ABS.However,the elongation at break and tensile strength of the modified nano-CaCO₃/PP composites only decreased by 9.4%and 5.89%,respectively.The action mechanism of modified nano-CaCO₃ was preliminarily discussed as well.（4）The thermal stability analysis of the modified nano-CaCO₃/ABS and modified nano-CaCO₃/PP composites showed that the modified nano-CaCO₃ could inhibit the decomposition of both the ABS and PP composites and improve their thermal stability.（5）Analysis of the melt mass flow rate of modified nano-CaCO₃/ABS and modified nano-CaCO₃/PP composites showed that:when the addition of modified nano-CaCO₃ was less than 18%（for ABS）and 10%（for PP）,the addition of modified nano-CaCO₃ could improve the melt mass flow rate,thus ameliorate the processing properties of the composites.更多还原