论文标题
使用微流体原理将相变材料封装到聚合物柔性纤维中的轻松方法
A facile approach for phase change material encapsulation into polymeric flexible fibers using microfluidic principles
论文作者
论文摘要
人们普遍认为，相变材料（PCM）对可持续能源未来具有很高的兴趣。许多应用都需要PCM的抗泄漏特性，这可以通过PCM封装来完成。在这项研究中，基于微流体原理的可扩展性和相当简化的方法是为聚偏氟化物（PVDF）空心设计的，以及无泄漏的石蜡/PVDF鞘纤维生产。所需的设备可以像注射器+管+玻璃毛细管一样简单。纤维是由PVDF/N，ndimethylformamide（DMF）溶液和PVDF/DMF/Popaffin乳液在水中注入的纤维，然后进行溶剂提取过程。提出的方法可导致空心PVDF或PVDF/Popaffin复合纤维，其PCM含量在32-47.5％之间，根据DSC和TGA测量值。对纤维形态的SEM研究表明，PCM处于沿纤维的sl弹性形式。这种PCM分布一直保持到第一个熔化周期。后来，熔融PCM在毛细管下通过红外摄像机捕获的纤维纤维散布。测量弹性模块和应力与应变，以表征设计纤维的机械性能。最后，复合纤维在1000熔化/结晶周期后仅显示出出色的保留能力，只有3.5％的PCM质量松动。
It is widely agreed that phase change materials (PCMs) are of high interest for sustainable energy future. Many of the applications require anti-leakage properties of PCM, that can be accomplished through PCM encapsulation. In this study, scalable and considerably simplified approach based on the microfluidics principles was successfully designed for polyvinylidene fluoride (PVDF) hollow- and for leakage-free paraffin-core/PVDF-sheath fibers production. The required device can be as simple as syringe+tube+glass capillary. The fibers were created by PVDF/N,NDimethylformamide (DMF) solution and PVDF/DMF/paraffin emulsion injection in water followed by solvent extraction process. The proposed approach results in a hollow PVDF or PVDF/paraffin composite fibers with the PCM content between 32-47.5% according to DSC and TGA measurements. SEM study of the fibers morphology has shown that PCM is in the form of slugs along the fibers. Such PCM distribution is maintained until the first melting cycle. Later, molten PCM spreads within the fiber under capillary forces that was captured by infrared camera. Elastic modules and stress vs. strain were measured to characterise mechanical properties of designed fibers. Finally, the composite fibers have shown outstanding retention capacity with only 3.5% of PCM mass loose after 1000 melting/crystallisation cycles.
