Tailoring of polyesters for bead foams with enhanced thermal resistivity and investigation of structure-property-relationships during expansion and fusion

具有增强耐热性的珠状泡沫聚酯的定制以及膨胀和熔融过程中结构-性能-关系的研究

• 批准号: 436509183
• 负责人: Privatdozentin Dr. Doris Pospiech
• 金额: --
• 依托单位: Leibniz-Institut für Polymerforschung Dresden (IPF)
• 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/436509183?language=en
• 关键词: Tailoring; polyesters; bead; foams; enhanced

The main goal of the proposed project is to scientifically explain and understand the complex effects that are happening during the expansion and fusion of bead foams from the engineering polymer polybutylene terephthalate (PBT). These PBT bead foams (E-PBT) are newly developed and possess a higher heat stability compared to the established bead foams from polystyrene (EPS, approx. 80 °C) and polypropylene (EPP, approx. 110 °C). A good foaming with an even morphology and welding of E-PBT is currently only possible with an epoxy chain extender (CE). However, this CE induces changes in the polymer chains and thereby also the rheological behavior is different leading to different expansion. By now, it is not possible to explain the welding behavior of E-PBT due to the complex reactions of the CE. So far, no deeper correlation of the molecular structure and the foaming/welding behavior was found. Therefore, PBT with systematically varied structures (linear, branched, cross-linked etc.) will be made and investigated regarding their rheological behavior (elongational, shear and melt strength). Foaming will be carried out firstly in a lab scale with an autoclave to determine the expansion behavior. Based on these result the most promising systems will be bead foamed on a larger scale. The fusion of E-PBT differs significantly from the established bead foams and is yet not understood. Here, the main focus will be the surface investigation to explain the effects during the fusion in the steam chest moulding machine. By modifying the polymer and consequently the beads surface it would be possible to influence the welding performance.

该项目的主要目标是科学地解释和理解工程聚合物聚对苯二甲酸丁二酯（PBT）泡沫泡沫膨胀和融合过程中发生的复杂效应。这些PBT泡沫珠（E-PBT）是新开发的，与现有的聚苯乙烯泡沫珠（EPS）相比，具有更高的热稳定性。80°C)和聚丙烯(EPP，约。110°C)。目前，只有环氧扩链剂（CE）才能使E-PBT具有均匀的形貌和良好的发泡性。然而，这种CE引起了聚合物链的变化，从而导致了不同的流变行为，导致了不同的膨胀。由于CE的复杂反应，目前还无法解释E-PBT的焊接行为。到目前为止，还没有发现分子结构与发泡/焊接行为的更深层次的关系。因此，将制造具有系统变化结构（线性，分支，交联等）的PBT，并研究其流变行为（伸长，剪切和熔融强度）。发泡将首先在实验室规模的高压灭菌器中进行，以确定膨胀行为。基于这些结果，最有前途的系统将在更大的规模上进行泡沫化。E-PBT的融合与现有的泡沫泡沫有很大的不同，目前还不清楚。在这里，主要的重点将是表面调查，以解释在蒸汽箱成型机的融合过程中的影响。通过改变聚合物，从而改变焊珠表面，有可能影响焊接性能。