Nowadays, the investigation of smart methods promoting PVDF β phase has become an important research topic in many energy related fields. In this work, compression moulding was proposed as an effective, simple and easy-scalable technique to tune PVDF polymorphism and obtain the desired crystalline form, exploiting a procedure in two steps. After a preliminary principal component analysis of the infrared spectra, the different moulding conditions tested were correlated with the electroactive phase amount, obtaining a non-monotonous trend. Finally, dielectric and dynamic-mechanical measurements were carried out on selected samples. Experimental evidence indicates that the double-step moulding induces the β phase formation due to the orienting effect generated by the shear stresses in the not completely molten polymer. Moreover, this method determines an increase in permittivity, a reduction of the dielectric losses and a change of PVDF molecular relaxations with respect to the reference film moulded through a simple single-step moulding.

如今，研究促进PVDFβ相的智能方法已成为许多能源相关领域的重要研究课题。在这项工作中，提出了压缩模塑法，它是一种有效，简单且易于扩展的技术，可通过两步过程来调整PVDF多态性并获得所需的晶形。在对红外光谱进行初步的主成分分析后，将测试的不同成型条件与电活性相量相关联，获得了非单调趋势。最后，对选定的样品进行了介电和动态机械测量。实验证据表明，由于未完全熔融的聚合物中的剪切应力所产生的定向作用，双步模塑法诱导了β相的形成。此外，