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特点是不断努力提高工艺的经济效益，同时保证高熔体质量。通常，这意味着相同大小的机器的吞吐量的增加。在过去的几十年里，与螺杆直径相关的吞吐量显着增长。沟槽衬套、更强大的驱动器和优化螺杆几何形状的使用极大地促进了这一发展。但这种方法已经达到了极限。通过提高螺杆的转速可以进一步提高机器的吞吐量（无需增加螺杆直径）。将能量输入从扭矩转移到转速还可以使用直接的无齿轮驱动器，从而避免变速箱损失。除此之外，通过减少与吞吐量相关的热损失的表面积，可以降低挤出机的功耗。此类机器尺寸的减小是另一个显着的好处。更小的通道体积带来了更多优点，因为它减少了材料的停留时间。这样可以减少材料降解，加快材料和工作点的变化。但是，高速机器方法受到工艺工程的限制。料斗进料供应不良、脉冲输出的物料进料不均匀以及熔体温度过高是必须考虑的一些方面。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，大多数有关高螺杆速度的研究工作都集中在半结晶热塑性塑料（尤其是聚乙烯和聚丙烯等聚烯烃）上。因此，大多数发现都来自这些材料的特定性能。到目前为止，只有少数关于非晶态热塑性塑料的结果。由于与半结晶热塑性塑料的结构不同，非晶态热塑性塑料在固体输送、熔化和材料降解方面的加工特性有所不同。本研究项目的目的是通过分析物理特性来了解非晶态热塑性塑料的加工过程并开发设计规则。在高螺杆转速 (2100rpm) 下加工这些材料时的影响。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集中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和测试优化的螺杆。