Effects of thermal cycling on phenylethynyl-terminated PMDA-type asymmetric polyimide composites

Zhang, Yixiang; Miyauchi, Masahiko; Nutt, Steven

doi:10.1177/0954008318804046

Cited by 3 publications

(2 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The stress caused by thermal cycling cannot exceed 50% of the tensile strength of PEPA-terminated polyimide for this thermal-cycling condition. 8 Thus, the polymer matrix is expected to resist microcracking during the thermal cycles used (−54°C to 232°C).…”

Section: Resultsmentioning

confidence: 99%

“…The superior strength retention was attributed to the greater oxidative stability and the greater tensile strength of the PEPA-terminated polyimide matrix. 8 Void-free PEPA-terminated polyimide composites, PETI-340M, show no cracks or voids after thermal cycling from −54°C to 232°C for 1600 cycles. The superior strength retention of PEPA-terminated polyimide composites indicates potential for long-term structural use in aerospace applications.…”

Section: Discussionmentioning

confidence: 96%

See 1 more Smart Citation

Thermo-oxidative aging and thermal cycling of PETI-340M composites

Jin

Tsotsis

et al. 2021

High Performance Polymers

Self Cite

View full text Add to dashboard Cite

Polyimide composites (PETI-340M) were fabricated and subjected to high-temperature aging and thermal cycling to evaluate resistance to degradation. Mechanical-degradation mechanisms and kinetics depended on aging temperature. Aging at 232°C resulted in strength loss due to polymer degradation, while intra-tow cracking was the dominant mechanism during aging at 288°C. Composite panels subjected to thermal-cycling fatigue (−54°C to 232°C) retained mechanical properties without microcracking. However, in regions containing pre-existing fabrication-induced defects (primarily voids), intra-tow microcracks were observed after thermal cycling. Unlike some polyimide composites (PMR-15), oxidative aging effects during thermal cycling were negligible. The thermo-oxidative stability and the retention of mechanical performance after thermal cycling indicates potential for long-term, high-temperature structural applications.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 96%

Thermo-oxidative aging and thermal cycling of PETI-340M composites

Jin

Tsotsis

et al. 2021

High Performance Polymers

Self Cite

View full text Add to dashboard Cite

show abstract

Thermal protective and hydrophobic coating on polyimide resin matrix composites surface for improved aging resistance

Fan,

Xiong,

Yin

et al. 2024

Polymer Composites

View full text Add to dashboard Cite

Polyimide composites are easily degraded in high temperature and high humidity environments for long service, which reduces their reliability and stability in aerospace, electronic components, weapons, and other fields. In this paper, the inorganic and organic multiphase double‐layer coating was prepared. The insulating layer was made of vinyl polysilazane resin as the base material and hollow glass microspheres as the filler. The hydrophobic layer consisted of polydimethylsiloxane as the base material, hollow phenolic microspheres, and nano‐TiO2 as the filler. The heat resistance, hydrophobic properties, and aging resistance of the coated polyimide resin matrix composites were studied. The results showed that the thickness of the double‐layer coating was about 200 μm. Under the 200°C thermal insulation test, the maximum temperature drop can be achieved at 59.7°C. After adding 5 wt% TiO2, the static contact angle of composites was increased from 86.2° to 127.7°. Significantly, the hydrophobic performance was improved by 48.1%, which was due to the construction of micro‐nano structures in the surface layer coating. In the accelerated hydrothermal aging tests, the bending properties of coated composite materials can be improved by 8.5%, 3.2%, and 8.7% in water, alkali, and acid environments, respectively. The moisture absorption of glass fiber and the pyrolysis of polyimide led to the degradation of the mechanical properties. The existence of heat‐resistant and hydrophobic coating could effectively eliminate this adverse effect, which was of great significance for polyimide composites to cope with various service environments.Highlights A novel coating consisting of thermal insulating and hydrophobic layers was developed on glass fiber reinforced polyimide composites (G/PI) composites. The maximum temperature drop of coating can be achieved at 59.7°C. The static contact angle of coated G/PI composites was increased from 86.2° to 127.7°. In the aging tests, the protective effect of the coating resulted in improved mechanical strengths of G/PI composites. The microscopic damage morphology was performed to analyze the anti‐aging properties of the coating.

show abstract