Investigating the Effects of Nitric Acid Treatments on the Properties of Recycled Carbon Fiber
In this study, the chemical state change of recycled carbon fiber (rCF) surfaces and the mechanism of the oxygen functional groups according to nitric acid treatment at various times and temperatures were investigated to upcycle the carbon fiber recovered from used carbon composite. When treated wit...
Main Authors: | , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
MDPI AG
2023-02-01
|
Series: | Polymers |
Subjects: | |
Online Access: | https://www.mdpi.com/2073-4360/15/4/824 |
_version_ | 1797618489662373888 |
---|---|
author | Gyungha Kim Hyunkyung Lee Minsu Kim Dae Up Kim |
author_facet | Gyungha Kim Hyunkyung Lee Minsu Kim Dae Up Kim |
author_sort | Gyungha Kim |
collection | DOAJ |
description | In this study, the chemical state change of recycled carbon fiber (rCF) surfaces and the mechanism of the oxygen functional groups according to nitric acid treatment at various times and temperatures were investigated to upcycle the carbon fiber recovered from used carbon composite. When treated with nitric acid at 25 °C, the carbon fiber surface demonstrated the same tensile properties as untreated carbon fiber (CF) for up to 5 h, and the oxygen functional group and polar surface energy of C–O (hydroxyl group) and C=O (carbonyl group) increased slightly compared to the untreated CF up to 5 h. On the other hand, at 100 °C, the tensile properties slightly decreased compared to untreated CF up to 5 h, and the amount of C–O and C=O decreased and the amount of O=C–O (lactone group) started to increase until 1 h. After 1 h, the amount of C-O and C=O decreased significantly, and the amount of O=C–O increased rapidly. At 5 h, the amount of oxygen functional groups increased by 92%, and the polar surface energy increased by 200% compared to desized CF. It was determined that the interfacial bonding force increased the most because the oxygen functional group, O=C–O, increased greatly at 100 °C and 5 h. |
first_indexed | 2024-03-11T08:14:32Z |
format | Article |
id | doaj.art-217f3aaaf8a64dafacd62ab13e9c2873 |
institution | Directory Open Access Journal |
issn | 2073-4360 |
language | English |
last_indexed | 2024-03-11T08:14:32Z |
publishDate | 2023-02-01 |
publisher | MDPI AG |
record_format | Article |
series | Polymers |
spelling | doaj.art-217f3aaaf8a64dafacd62ab13e9c28732023-11-16T22:50:26ZengMDPI AGPolymers2073-43602023-02-0115482410.3390/polym15040824Investigating the Effects of Nitric Acid Treatments on the Properties of Recycled Carbon FiberGyungha Kim0Hyunkyung Lee1Minsu Kim2Dae Up Kim3Carbon & Light Materials Application Group, Korea Institute of Industrial Technology, 222 Palbok-ro, Deokjin-gu, Jeonju 54853, Republic of KoreaCarbon & Light Materials Application Group, Korea Institute of Industrial Technology, 222 Palbok-ro, Deokjin-gu, Jeonju 54853, Republic of KoreaCarbon & Light Materials Application Group, Korea Institute of Industrial Technology, 222 Palbok-ro, Deokjin-gu, Jeonju 54853, Republic of KoreaCarbon & Light Materials Application Group, Korea Institute of Industrial Technology, 222 Palbok-ro, Deokjin-gu, Jeonju 54853, Republic of KoreaIn this study, the chemical state change of recycled carbon fiber (rCF) surfaces and the mechanism of the oxygen functional groups according to nitric acid treatment at various times and temperatures were investigated to upcycle the carbon fiber recovered from used carbon composite. When treated with nitric acid at 25 °C, the carbon fiber surface demonstrated the same tensile properties as untreated carbon fiber (CF) for up to 5 h, and the oxygen functional group and polar surface energy of C–O (hydroxyl group) and C=O (carbonyl group) increased slightly compared to the untreated CF up to 5 h. On the other hand, at 100 °C, the tensile properties slightly decreased compared to untreated CF up to 5 h, and the amount of C–O and C=O decreased and the amount of O=C–O (lactone group) started to increase until 1 h. After 1 h, the amount of C-O and C=O decreased significantly, and the amount of O=C–O increased rapidly. At 5 h, the amount of oxygen functional groups increased by 92%, and the polar surface energy increased by 200% compared to desized CF. It was determined that the interfacial bonding force increased the most because the oxygen functional group, O=C–O, increased greatly at 100 °C and 5 h.https://www.mdpi.com/2073-4360/15/4/824recycled carbon fibernitric acidfunctional groupsurface free energymechanism |
spellingShingle | Gyungha Kim Hyunkyung Lee Minsu Kim Dae Up Kim Investigating the Effects of Nitric Acid Treatments on the Properties of Recycled Carbon Fiber Polymers recycled carbon fiber nitric acid functional group surface free energy mechanism |
title | Investigating the Effects of Nitric Acid Treatments on the Properties of Recycled Carbon Fiber |
title_full | Investigating the Effects of Nitric Acid Treatments on the Properties of Recycled Carbon Fiber |
title_fullStr | Investigating the Effects of Nitric Acid Treatments on the Properties of Recycled Carbon Fiber |
title_full_unstemmed | Investigating the Effects of Nitric Acid Treatments on the Properties of Recycled Carbon Fiber |
title_short | Investigating the Effects of Nitric Acid Treatments on the Properties of Recycled Carbon Fiber |
title_sort | investigating the effects of nitric acid treatments on the properties of recycled carbon fiber |
topic | recycled carbon fiber nitric acid functional group surface free energy mechanism |
url | https://www.mdpi.com/2073-4360/15/4/824 |
work_keys_str_mv | AT gyunghakim investigatingtheeffectsofnitricacidtreatmentsonthepropertiesofrecycledcarbonfiber AT hyunkyunglee investigatingtheeffectsofnitricacidtreatmentsonthepropertiesofrecycledcarbonfiber AT minsukim investigatingtheeffectsofnitricacidtreatmentsonthepropertiesofrecycledcarbonfiber AT daeupkim investigatingtheeffectsofnitricacidtreatmentsonthepropertiesofrecycledcarbonfiber |