通过掺杂柔性二胺单体增强聚酰亚胺性能:分子动力学模拟

聚酰亚胺(PI)被视为一类以其卓越性能而闻名的高性能聚合物材料。传统聚酰亚胺的一个关键问题是其熔体的加工性能较差。在本研究中,设计了一种新的聚酰亚胺单体Am-Di,其特点是由氮原子连接的苯环组成的柔性结构。通过详尽的研究,我们对Am-Di掺杂到聚酰亚胺中对其玻璃化转变温度、均方位移、力学性能和相对介电常数等性质的影响进行了深入探讨。结果表明,在聚酰亚胺体系中,掺杂新型二胺可以加速聚酰亚胺分子链的运动,从而降低聚酰亚胺体系的玻璃化转变温度。在Am-Di掺杂量为20%的情况下,PI-20%表现出最高的弹性模量(4.505Gpa),比纯PI高1.2倍。此外,随着掺杂比例的增加,聚酰亚胺的相对介电常数降低。这些发现表明,Am-Di的掺杂对聚酰亚胺材料的性能具有积极影响,特别是在增强机械性能和调控电气性能方面,为进一步改进聚酰亚胺材料的设计和应用提供了有价值的见解。

Enhancing Performance of Polyimide through Doping with a Flexible Diamine Monomer: Molecular Dynamics Simulations

Polyimide (PI) is recognized as a class of high-performance polymer materials, renowned for its exceptional properties. A significant challenge faced by conventional polyimide lies in its suboptimal processing performance during melting. In the present investigation, a novel polyimide monomer, Am-Di, characterized by a flexible structure composed of benzene rings connected by nitrogen atoms, has been meticulously designed. Thorough examinations have been undertaken to assess the characteristics of various Am-Di doping levels in polyimide, focusing on the glass transition temperature, mean square displacement, mechanical properties, and relative permittivity. The findings reveal that incorporating the new diamine into the polyimide system accelerates the movement of polyimide molecular chains, thereby reducing the glass transition temperature. Notably, at an Am-Di doping level of 20%, PI-20% demonstrates the highest elastic modulus (4.505 Gpa), surpassing pure PI by 1.2 times. Additionally, the relative dielectric constant of polyimides decreases proportionally with an increase in the doping ratio. These results underscore the positive impact of Am-Di doping on polyimide properties, particularly in enhancing mechanical performance and adjusting electrical properties. These insights offer valuable guidance for further advancements in the design and application of polyimide materials.