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Abstract The current study confirms that modified carbon fiber reinforced polymer (CFRP) composites have higher fracture toughness than unmodified CFRP composites achieved by exploiting the synergistic effect of a polycarbonate (PC)/acrylonitrile butadiene styrene (ABS) blend in toughening the diglycidyl ether of bisphenol A (DGEBA) epoxy resin. The CFRP composite specimens are tested at near cryogenic temperatures using TMA, DMA, and microcrack analysis to determine the best‐suited concentration of ABS in the PC/ABS blend. TMA and DMA results, as well as microcrack analysis at cryogenic temperatures (CT), confirm that the blend 90/10 is effective in reducing the brittle nature of DGEBA resin and increasing bond strength, resulting in the fracture toughness enhancement of CFRP specimens at CT. Further investigation of 90/10 modified CFRP (90/10 m‐CFRP) and unmodified CFRP specimens using Mode II fracture using ENF test and SEM analysis reveal significant reduction in brittle characteristics of matrix with increase in elongation at failure and fracture surface morphologies confirm nano web‐like structures bridging the CF layers, proving to improve fiber/matrix bond strength. This study concludes the effectiveness of hybrid PC/ABS blend in synergistically‐modifying DGEBA resin for improved fracture toughness of CFRP laminates across a wide temperature range (−150°C to 150°C).
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Thermal Synergistic Effect on CFRP Laminates with Modified Fiber/Matrix Systems for Heat Transfer Applications
Abstract Carbon fiber reinforced polymer (CFRP) laminates are modified to enhance their suitability for various thermal applications. A synergistic approach utilizing the effect of various conductive and insulative modifiers with diglycidyl ethers of bisphenol A (DGEBA) epoxy resin and/carbon fiber (CF) is explored. In CFRP laminates developed after modifications made in epoxy resin using a thermoplastic material, such as polycarbonate (PC) and/or acrylonitrile butadiene styrene (ABS), exhibit high thermal resistance (TR) of 77.1% compared to unmodified CFRP. In contrast, modifications made using conductive mediums like phosphonium (P), imidazolium (I), or silanized‐graphene oxide (SGO) have lower TR of 25.7%, 30.5%, and 32.4%, respectively. A temperature gradient (TG) enhancement of 75% is reported for the 1.5 wt% PC/ABS modified CFRP laminates. On the contrary, modifications using 0.5 parts per hundred (phr)P, 0.5 phr I, and 1 g L−1SGO in epoxy reduce the TG by 25%, 30%, and 32%, respectively. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analyses are done to explore the thermal characteristics of each case of modification. Finally, scanning electron microscopy images confirm the distribution profile of the modifiers used. Based on the types of modifications performed, the current study can offer insightful information on the thermal performances of modified CFRP laminates.
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- Award ID(s):
- 1719875
- PAR ID:
- 10548205
- Publisher / Repository:
- Wiley Online Library
- Date Published:
- Journal Name:
- Macromolecular Chemistry and Physics
- Volume:
- 224
- Issue:
- 11
- ISSN:
- 1022-1352
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/macp.202200462
