【作者】 何波兵；

【导师】 傅强；

【作者基本信息】 四川大学 ， 高分子化学与物理， 2006， 博士

【摘要】 加工过程的在线检测与控制是提高制品性能的重要手段。超声波作为一种机械波,具有探头安装简单方便、不破坏检测对象、信号反馈速度快、内容丰富等优点,在高分子加工检测中具有广阔的应用前景。本论文以超声技术对具有不同相容性和相形态结构的PP/PS, PS/EPDM, PS/SBS, PVC/NBR聚合物共混体系,以及通过动态保压注射成型制得的具不同取向结构的HDPE/iPP共混物进行了检测,阐明了超声信号与聚合物形态结构之间的关系。另外,将超声技术用于注塑成型过程的在线检测,探索了超声技术对过程的检测能力,研究了结晶与非晶高聚物注塑充模过程的超声行为,以及温度、压强、注射量等条件对聚合物冷却固化行为的影响规律。拓展了超声技术的应用领域,对加工过程的可视化研究以及过程和制品的最优化研究具有重要的理论意义和实用价值。主要研究结果如下:1.超声衰减可表征聚合物共混物的相容性和相形态结构。相容体系中(如PVC/NBR)组分之间分散良好,无大尺寸的分散粒子引起超声散射衰减,衰减与组分含量呈直线关系。在不相容共混物中(如PP/PS,PS/EPDM),衰减与组分含量呈非线性关系。由于存在尺寸较大的分散相粒子,这些分散粒子引起超声散射衰减,随分散相含量增加,分散粒子尺寸增大,其引起的散射衰减响应增加,在相转变区,体系呈双连续结构,分散相含量达到最大值,分散粒子尺寸也达最大值并相互连接成连续相,体系的超声衰减达到最大值,此最大值对应于衰减-组分含量曲线的拐点。因此,通过检测超声衰减随不相容共混物组成的变化,可以建立简便快速的表征共混物相反转的有更多还原

【Abstract】 In-situ monitoring and controlling are of importance for improving final product performance during processing. Ultrasound, a kind of mechanical wave, has extremely potential applications in the field of polymer processing for its super advantages, such as convenient installation, non-invasion and non-destruction, quick feedback, et al. In this dissertation, the miscibility and phase morphologies of polymer blends like PP/PS, PS/EPDM, PS/SBS, PVC/NBR, and orientation structures of HDPE/iPP blend obtained by dynamic packing injection molding were investigated using ultrasonic technique, and the relationships between ultrasonic signals and polymer structures had been found. In addition, ultrasonic technique was employed to monitor the injection molding process. Therein, the solidification behaviors of amorphous polymer and crystalline polymer, as well as the effect of temperature, pressure and injection mount on solidification were studied using ultrasound. This work is important for the optimization of process and product performances theoretically and practically.Major results are:1. Ultrasonic attenuation can characterize the miscibility and phase morphologies of polymer blends. Attenuation varies linearly with composition in miscible blends like PVC/NBR in that good miscibility results in a homogenous system and no ultrasonic scattering loss occurs. However, the comparable dispersed particles in immiscible polymer blends cause scattering loss which increases with increasing in particle size and dispersed phase content, consequently, the更多还原