GJB 3381A-2021
Specification for bismaleimide resin (English Version)
- Standard No.
- GJB 3381A-2021
- Language
- Chinese, Available in English version
- Release Date
- 2021
- Published By
- Military Standard of the People's Republic of China-General Armament Department
- Latest
- GJB 3381A-2021
- Introduction
Standard Evolution and Technological Breakthroughs
GJB 3381A-2021, as the latest technical specification for bismaleimide resin of our army, has achieved three major technological breakthroughs: adding 11 new resin systems such as QY9611, optimizing the viscosity test method, and reconstructing the resin classification system. For the first time, this standard raises the maximum operating temperature to 265±8℃ (QY260), which improves the temperature resistance by 15% compared with the 1998 version of the standard.
Analysis of core performance indicators
Performance parameters Prepreg resin Liquid molding resin Test standard Maximum exotherm temperature 217-265℃ 250-260℃ HB 7614 Viscosity range 0.2-13 Pa·s 0.25-1 Pa·s Rotational rheometer Glass transition temperature ≥200℃ ≥220℃ GB/T 22567
Key Change Comparison
Technical Architecture Reconstruction: The new standard changes the resin classification from "component/state" to "purpose classification", forming two major systems: prepreg resin (including 9 types such as 5405) and liquid molding resin (including 4 types such as 6421A). Among them, the viscosity of QY8911-IV type resin is ≤0.25Pa·s after being kept at 90℃ for 4h, which is particularly suitable for RTM process.
Test method upgrade: The viscosity test adopts dynamic mechanical analysis (DMA), and the heating rate is precisely controlled at 2-3℃/min, which improves the test accuracy by 40% compared with the old standard.
Implementation and application suggestions
- Material selection:For high temperature environment (＞230℃), QY260 resin is preferred, and its Tg value reaches 260℃
- Process control:The temperature deviation during the curing stage is strictly controlled within ±5℃, and the time deviation is ≤15min
- Storage management:The solid resin has a storage period of 12 months at -18℃ (except BH301), and the solution resin needs to be stored away from light
Infrared spectral feature library
Appendix A of the standard establishes a complete infrared spectral database, such as QY260. The characteristic peaks of class=instrument>5405 resin are 3465±10cm-1 (NH stretching vibration) and 1712±10cm-1 (C=O stretching vibration), which provide a reliable basis for material identification.
GJB 3381A-2021 history
- 2021 GJB 3381A-2021 Specification for bismaleimide resin
- 1998 GJB 3381-1998 Specification for bismaleimide resin