【作者】 李利；

【导师】 汪传生；

【作者基本信息】 北京化工大学 ， 化工过程机械， 2008， 博士

【摘要】 混炼过程和挤出成型过程一直以来都是橡胶等聚合物加工过程中各自独立的重要环节。随着近年来橡塑共混技术的发展,特别是以塑料为基体的橡塑共混物的广泛应用,使得传统技术装备已无法满足工业化生产的要求。本文在国家自然科学基金资助下,重点针对上述问题,提出了一种新型的、具有较强适应性的共混聚合物混炼成型加工一体化设备——混炼成型一体机。该设备兼具有密炼机的优良混炼性能和挤出机的连续挤出成型加工的特点,使混炼和挤出成型两道工序在同一台设备上完成。本文以这种新的加工方法为对象,主要进行以下研究工作:1、经过一系列的方案论证,自主开发设计了新型混炼成型一体机。其转子构型新颖,整机系统驱动方式既可采用液压驱动也可采用特殊的机械驱动,转子及螺杆均可实现无级调速,在保证良好混炼性能的同时,使密炼机的加料与挤出机的出料匹配。它突破了密炼机间歇式生产方式的局限,使混炼与成型在同一台设备上连续进行,开创了高聚物混炼加工的“间歇式生产+连续性生产”的新型的生产模式,实现了用同一台设备高聚物从原料到制品的转换。2、对混炼成型一体机的转子构型、混炼机理及混炼理论进行了详细研究。在结合功能转子的造型及设计要求的基础上,对转子在混炼及排胶两个过程中对胶料的受力及运动方式进行分析,确保转子具有混炼及排胶的双重功能。建立混炼成型一体机混炼理论的数学方程,可作为验证计算机流场模拟结果的依据。3、详细探讨了混炼成型一体机的挤出成型理论,由于从混炼室排出的胶料温度超过100℃,因此在整个挤出过程中胶料为粘性流体,根据现有的粘性流体挤出理论得出本实验机台的挤出生产能力与其他参数间的数学方程。4、根据密炼机和挤出机的生产能力和有关影响因素,建立起挤出机与密炼机协互相调、连续生产的混炼成型连续化数学方程,并指出了影响混炼成型连续化的因素,为相关的实验研究提供了理论支持。5、利用ADINA软件分别对混炼部分和挤出成型部分进行了流场的有限元分析。流场分析的结果验证了胶料的受力分析、物理数学模型和相关数学方程的正确性,并为后续的实验研究指明了方向。6、为了保证混炼成型一体机的混炼性能,设计了三种不同构型的转子,并结合传统的同步二棱和同步四棱共五对转子,进行了500多车次的对比实验研究。对各种转子的最佳工艺条件进行了讨论,找出了影响混炼过程的最佳的混炼工艺参数,为混炼成型一体机的进一步的实验研究,提供工艺参数的选择依据;实验数据分析表明三对新型转子中,功能二棱同步转子的混炼效果最好,其次是销钉式二棱同步转子。同时,转子的对比实验结果也验证了相关理论分析和转子流场分析结果的正确性。7、通过对混炼成型一体机的实验研究,验证并完善了混炼成型连续化的数学模型;混炼成型一体机产品性能测试的结果,说明了本设备加工性能的可靠性,为本设备的推广应用奠定了基础。8、通过二次回归正交方法建立了功能二棱同步转子的工程实用数学模型,并对预测值和实验数据进行了比较,相对误差较小,预测精度较高,能够反映新型混炼成型一体机转子的混炼特性,适合对新型混炼成型一体机的混炼过程进行预测和分析。本文通过理论研究、流场模拟及实验研究表明所研究开发的混炼成型一体机技术是可行的。通过流场模拟和实验验证,表明本文所建立的混炼成型机理及混炼成型连续化理论是正确的,对于开发工业化应用机台具有重要的指导意义。更多还原

【Abstract】 Mixing and extrusion molding have been two independent and important steps of polymer processing. With the progress of the blending technology for rubber-plastics and rubber-rubber, especially the wide use of rubber plastics blends, the traditional technical equipments can’t meet the requirement of the industrial production. So new type equipment for mixing and molding of polymer blend, the mixing-molding integrative machine is developed in this paper. The equipment, on which the process of mixing and extruding can both be finished, has the advantage of both internal mixer and extruder. The following research work on this equipment has been done:1. The new type mixing-molding integrative machine with novel rotor configuration was designed. Both the hydraulic drive and the mechanical drive, together with the stepless speed regulation of rotor and s, are available in this machine to get the good mixing properties. As a result, the feedstock of internal mixer can match well with the discharge of the extruder. The most important thing of the machine is that both mixing and molding can be finished on it, for which the process from raw material to product can be finished by one set of machine.2. The thorough study on the rotor configuration and the mixing theory was made. The stress and movement mode of the compound when mixed and discharged were analyzed. And the mathematical equation of mixing theory is set up for the mixing-molding integrative machine, which can be used to verify the computer simulation result of fluid field.3. The extrusion molding theory was thoroughly studied. With the discharge rubber compound temperature above 100℃, the compound is in the state of viscous fluid. So it was according to the extrusion theory for viscous fluid that the mathematical equation of the relation between extrusion production capacity and other parameters for this machine is concluded in this paper.4. According to the production capacity of internal mixer and extruder, together with it’s influence factors, the mathematical equation for the continuous process of mixing and molding was set up, which can act as the theoretical basis of the experimental research.5. The finite analysis of the fluid field in the process of mixing and molding was performed with the help of ADINA. The result of the analysis proves that the stress analysis of the rubber compound, together with the physical and mathematical models, is correct, which supply the basis of the following experimental research.6. Three rotors with different configuration were designed and 500 contrast experiments for the designed rotors and traditional rotors were performed. At the same time, the optimum process condition for the rotors and the optimum process parameters for the mixing process were discussed in this paper. The analysis result shows that functional two-wing synchronous rotors are best for the mixing effect and the pinned two-wing synchronous rotors are the second, which also proves that the connecting theory analysis is correct.7. The experimental research of the mixing-molding integrative machine verifies and improves the mathematical model of the continuous mixing and molding. The testing result of the machine proves that its processing properties are reliable, which sets the basis for the popularization and application of the machine.8. The engineering mathematical model was set up for the functional two-wing synchronous rotors with the help of the quadratic regression cross method. And the predictive value and the experimental value were compared, which showed that the precision of the forecasting model was very good. So the model can be used to predict and analyze the mixing process for the new type mixing-molding integrative machine.The theory research, the flow field simulation, and the experimental research in this paper all show that the developed mixing-molding integrative machine is feasible. The flow field simulation and the experimental research show that the mixing and molding principle and the continuous process theory, which was set up in this paper, are correct and useful for the development of the industrial equipment.更多还原