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High Speed Extrusion of amorphous Polymers using the Example of Polycarbonate (PC) and Polymethylmethacrylate (PMMA)

以聚碳酸酯 (PC) 和聚甲基丙烯酸甲酯 (PMMA) 为例非晶态聚合物的高速挤出

基本信息

批准号：
238881183
负责人：
Professor Dr.-Ing. Volker Schöppner
金额：
--
依托单位：
Fachgebiet Kunststoffverarbeitung
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2013
资助国家：
德国
起止时间：
2012-12-31 至 2019-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/238881183?language=en
关键词：
Speed Extrusion amorphous Polymers using

项目摘要

New developments in the field of single screw plastification are characterised by continually endeavouring to raise the process' economic efficiency and to simultaneously guarantee a high melt quality. As a rule, this signifies an increase in the throughput for the same size of machine. The screw diameter related throughput has grown significantly in the past decades. Grooved bushes, more powerful drives and the use of optimised screw geometries have substantially contributed to this development. But this approach has come to its limits.A further increase in the throughput of a machine (without increasing the screw diameter) can be obtained by increasing the screw's rotational speed. Shifting the energy input from the torque to the rotational speed also enables direct, gearless drives to be used so that gearbox losses can be avoided. Besides this, the extruder's power consumption is lowered by means of the reduced surface area for throughput-related heat loss. The reduced size of such machines is another significant benefit. Further advantages result from the smaller channel volumes since it reduces the material's residence time. This results in less material degradation and faster changes of the material and the operating point.However, the high-speed machine approach is subject to process engineering limitations. A poor hopper feed-supply of the material, a non-uniform material feed with pulsing output and too high melt temperatures are some of the aspects which must be taken into account. In particular, the melting behaviour also plays an important role owing to the extremely short residence times. Up to now most research work with reference to high screw speeds was focused on semi-crystalline thermoplastics (especially polyolefins like PE and PP). Hence most findings result from the specific properties of these materials.So far only a few results exist for amorphous thermoplastics. Due to a different structure compared to semi-crystalline thermoplastics, the processing characteristics of amorphous thermoplastics concerning solids conveying, melting and material degradation differ.The aim of this research project is to understand the process and develop design rules for processing amorphous thermoplastics by analyzing physical effects during the processing of these materials at high screw speeds (2100rpm). To this experimental investigations will be carried out. Process data will be examined as well as the mechanical and optical properties of the product (film). The extracted results will be analyzed by tightly focused simulative Methods to educe criteria to design process for the considered materials. To verify these results an optimized screw will be designed and tested with these criteria.

单螺杆塑化领域的新发展的特点是不断努力提高工艺的经济效率，同时保证高熔体质量。通常，这意味着对于相同大小的机器，吞吐量的增加。在过去的几十年中，螺杆直径相关的产量显著增长。带槽衬套、更强大的驱动器和优化的螺杆几何形状的使用大大促进了这一发展。但这种方法也有其局限性。通过提高螺杆转速可以进一步增加机器的产量（而不增加螺杆直径）。将能量输入从扭矩转换为转速还可以使用直接的无齿轮驱动，从而避免齿轮箱损失。除此之外，挤出机的功率消耗通过减少与产量相关的热损失的表面积而降低。这种机器的尺寸减小是另一个显著的好处。更小的通道体积带来了进一步的优势，因为它减少了材料的停留时间。这使得材料降解更少，材料和工作点的变化更快。然而，高速机床方法受到工艺工程的限制。必须考虑的一些方面是料斗进料不足、脉冲输出的不均匀进料和过高的熔体温度。特别是，由于停留时间极短，熔化行为也起着重要作用。到目前为止，大多数关于高螺杆转速的研究工作都集中在半结晶热塑性塑料（特别是聚烯烃，如PE和PP）上。因此，大多数研究结果都是由这些材料的特定性质引起的，而目前只有少数结果是针对无定形热塑性塑料的。与半结晶热塑性塑料相比，无定形热塑性塑料的结构不同，其固体输送、熔融和材料降解的加工特性也不同。本研究的目的是通过分析在高螺杆转速（2100 rpm）下加工无定形热塑性塑料时的物理效应，了解加工过程并制定加工无定形热塑性塑料的设计规则。为此，将进行实验研究。将检查工艺数据以及产品（薄膜）的机械和光学性能。提取的结果将通过紧密聚焦的模拟方法进行分析，以得出所考虑材料的设计过程的标准。为了验证这些结果，将根据这些标准设计并测试优化螺钉。