Analysis and modelling of the melting behavior of polymers in co-kneaders

共捏合机中聚合物熔融行为的分析和建模

• 批准号: 324376716
• 负责人: Professor Dr.-Ing. Martin Bastian
• 金额: --
• 依托单位: Süddeutsches Kunststoff-Zentrum
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/324376716?language=en
• 关键词: Analysis; modelling; melting; behavior; polymers

The gentle processing of plastics is a central component in the cycle of plastic products, particularly because of the constantly growing importance of biopolymers and recycling. In this context, the Co- Kneader represents a machine system which, based on its excellent homogenization properties and the low shear stress of the material, is well suited for demanding processing tasks. Due to the lack of models for this type of machine, the development of the Co-Kneader to today's degree of maturity is largely based on empirical knowledge and trial-and-error methods. Because of increasing requirements and more complex processes, this is increasingly becoming a problem. This is why the use of simulations has established itself in the development of extruders. Although first models have been published for Co-Kneaders to describe the process behavior, they neglect melting and are therefore only valid for pure melt conveyance. The aim of this project is therefore the investigation of the melting behavior of plastics in Co-Kneaders. In the first funding period, basic physicalmathematical models were developed to describe the melting processes. It was possible to describe the melting of granulates in the Co-Kneader with a disperse melting model. However, the models only lead to valid results if the melting corresponds to the location of the first full filling. In addition, energy input via plastic energy dissipation is neglected. In the second funding period, therefore, the modelling of the initial melting is to be improved. For this purpose, plastic energy dissipation will be modelled. Results from experimental investigations at the Co-Kneader as well as mechanical parameters will be used for the calibration of the models.

塑料的温和加工是塑料产品循环的核心组成部分，特别是因为生物聚合物和回收的重要性不断增长。在这种情况下，共捏合机代表了一种机器系统，该系统凭借其出色的均质特性和材料的低剪切应力，非常适合要求苛刻的加工任务。由于缺乏此类机器的模型，捏合机发展到今天的成熟程度很大程度上是基于经验知识和试错方法。由于要求不断增加和流程更加复杂，这日益成为一个问题。这就是为什么模拟的使用在挤出机的开发中得到了广泛应用。尽管已经发布了第一个共捏合机模型来描述工艺行为，但它们忽略了熔化，因此仅适用于纯熔体输送。因此，该项目的目的是研究共捏合机中塑料的熔化行为。在第一个资助期间，开发了基本的物理数学模型来描述熔化过程。可以使用分散熔融模型来描述共捏合机中颗粒的熔融。然而，只有当熔化对应于第一次完全填充的位置时，模型才会产生有效的结果。此外，通过塑性能量耗散的能量输入被忽略。因此，在第二个资助期，初始熔化的模型需要改进。为此，将对塑料能量耗散进行建模。混炼机实验研究的结果以及机械参数将用于模型的校准。