【作者】 吴其晔； 冯绍华； 熊忠； 陈骁； 李鹏； 王建新； 巫静安；

【Author】 Wu Qiye, Feng Shaohua, Xiong Zhong, Chen Xiao, Li Peng, Wang Jianxin, Wu Jingan (Qingdao University of Science and Technology, Qingdao 266042,

【机构】 青岛科技大学；

【摘要】 采用双毛细管流变仪详细研究了一批聚乙烯及其共聚物的挤出畸变、管壁滑移及挤出压力振荡现象。理论推导得到恒速型流变仪中熔体发生壁滑的滑移速度和临界外推滑移长度的计算方法和公式。计算结果与实验现象相符。实验发现线型大分子或带小侧基的大分子熔体,容易发生壁滑和挤出压力振荡;而有较大侧基、或分子量分布宽的材料挤出畸变现象较轻,实验未观察到压力振荡现象。挤出速度越大,压力振荡频率变大,周期变小,振幅变化不大。挤出温度升高,压力振荡频率减小,周期变大,外推滑移长度有变小趋势。更多还原

【Abstract】 The melt fracture behaviors of HDPE, EPDM, POE etc were studied by double capillary rheometers constant speed type. A method to analyse and to calculate the melt slide speed at wall vs and the critical slide length bc in the measurement was obtained. It is indicated, that the melt slide at wall andthe extrusion pressure vibration were easy occurred with linear macromolecule melts and difficulter occurred with polymer melts have biger side-group or broader molecule weight distribution. More the extrusion speed, the frequency of extrusion pressure vibration was higher, the period shorter, and the amplitude varied slight.更多还原