Hygrothermal behavior of polybenzimidazole

POLYMER

卷:93

Article

Liu, Peng¹  Mullins, Michael²  Bremner, Tim³  Browne, James A.⁴  Sue, Hung-Jue^1,2 

[1] Texas A&M Univ, Dept Mech Engn, College Stn, TX 77843 USA

[2] Texas A&M Univ, Dept Mat Sci & Engn, College Stn, TX 77843 USA

[3] Hoerbiger Corp Amer Inc, Houston, TX 77023 USA

[4] TA Instruments Waters LLC, New Castle, DE 19720 USA

关键词: Polybenzimidazole;    Degradation;    Moisture absorption;    Mechanical properties;   

DOI  :  10.1016/j.polymer.2016.04.020

来源: Elsevier

【 摘 要 】

Poly[2,2'-(m-phenylene)-5,5'-bibenzimidazole] (PBI) is used in extremely high temperature harsh environment applications. It is a unique engineering material that is formed into parts by powder-sintering at temperatures as high as 500 degrees C. Recently, ever increasing demands for high temperature polymers have led to significant interest in PBI such that engineering guidelines could be established for its application in high temperature and highly humid environments. The goal of this work was to understand the material science of PBI in hot-wet environments at temperatures up to 288 degrees C. Thermal gravimetric analysis and mass spectrometry were employed to identify the degraded volatile products. The molecular scale damping behavior of PBI was probed using dynamic mechanical analysis. The changes in tensile properties and fracture toughness due to environmental exposure were also characterized. Upon heating above 250 degrees C, moisture-containing PBI exhibits obvious molecular structure change. Evidence of crosslinking and degradation is observed. With 288 degrees C hot water treatment severe degradation of PBI is observed. Fundamental structure-property relationships of PBI affected by these higher temperature, high moisture content environments are discussed. (C) 2016 Elsevier Ltd. All rights reserved.

【 授权许可】

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