聚四氟乙烯纖維/聚酰亞胺低介電常數復合膜的制備及其性能分析

摘 要： 為了降低聚酰亞胺（PI）的介電常數和介電損耗，以加捻聚四氟乙烯（PTFE）纖維為中間層，PI膜為底層和表面層，制備PI/PTFE纖維/PI復合膜，并對復合膜的結構形貌、介電性能、擊穿強度、力學性能和熱性能進行系統分析。結果表明：復合膜保留了PTFE纖維的化學結構和高結晶度，并呈現出內含孔隙的PI/PTFE纖維/PI三明治結構；在制備復合膜時利用加捻PTFE纖維的低介電常數和低介電損耗的特性，同時在復合膜中引入空氣，可使制備所得復合膜具有較低的介電常數和介電損耗；在電場頻率為10 GHz時，復合膜的介電常數達到1.51，介電損耗達到0.001；復合膜的擊穿強度為93.8 kV/mm，較PI膜有所降低；復合膜縱向拉伸強度可達118.9 MPa，失重5%的溫度高達534℃，表現出良好的力學和熱學性能。該研究可為研發高頻電場下具有低介電性能的PI提供新的方法和實驗參考。

關鍵詞：三明治結構；聚四氟乙烯纖維；聚酰亞胺；低介電常數；復合膜

中圖分類號：TB383.2中圖分類號

文獻標志碼：文獻標志碼A

文章編號：1673-3851 （2025） 03-0139-07

引文格式：史帥達，傅雅琴. 聚四氟乙烯纖維/聚酰亞胺低介電常數復合膜的制備及其性能分析［J］. 浙江理工大學學報（自然科學），2025，53（2）：139-145.

Reference Format： SHI Shuaida，FU Yaqin. Preparation of a PTFE fiber/polyimide composite film with low dielectric constant and analysis of its properties［J］. Journal of Zhejiang Sci-Tech University，2025，53（2）：139-145.

Preparation of a PTFE fiber/polyimide composite film with low dielectric constant and analysis of its properties

SHI Shuaida， FU Yaqin

（School of Materials Science amp; Engineering， Zhejiang Sci-Tech University， Hangzhou 310018， China）

Abstract：To reduce the dielectric constant and dielectric loss of polyimide （PI）， a PI/PTFE fiber/PI composite film was prepared by using twisted PTFE fiber as the middle layer and PI film as the bottom and surface layers. The structure and morphology， dielectric properties， breakdown strength， mechanical properties and thermal properties of the composite film were systematically analyzed. The results showed that the composite film retained the chemical structure and high crystallinity of PTFE fibers， and presented the PI/PTFE fiber/PI sandwich structure containing pores; in the preparation of the composite film， the low dielectric constant and low dielectric loss properties of twisted PTFE fibers were utilized while air was introduced into the composite film， which made the composite film have a low dielectric constant and dielectric loss; when the electric field frequency was 10 GHz， the dielectric constant of the composite film reached 1.51 and the dielectric loss reached 0.001; the breakdown strength of the composite film was 93.8 kV/mm， lower than that of PI; its longitudinal tensile strength could reach 118.9 MPa， and the temperature of 5% weight loss was as high as 534℃， showing good mechanical and thermal properties. The study provides a new method and experimental reference for developing PI with low dielectric properties under a high frequency electric field.

Key words：sandwich structure; PTFE fiber; polyimide; low dielectric constant; composite film

0 引 言

近年來，隨著微電子工業、5G通信技術的高速發展，電子產品對高集成、耐高頻、高速和高功率特性的要求越來越高^［1-3］。層間介質材料較高的介電常數（D_k）和介電損耗（D_f）會導致串線干擾、信號傳輸滯后和傳輸功耗增加^［4］，這使得制備高頻工況下具有低介電性能的介質材料成為研究熱點。聚酰亞胺（PI）是一種性能優異的絕緣介質材料，因具有出色的熱穩定性、耐溶劑性、力學性能和介電性能，被廣泛應用于微電子、通信等行業^［5-7］。……