為達到環境永續發展，減少資源浪費，具有回收價值的碳纖維複合材料不應再視為廢物，而是可成為再度使用的材料。近年來許多研究機構或廠商紛紛投入化學分解法碳纖維回收技術，採用化學溶劑將基體樹脂和纖維分離，得到高品質的長纖碳纖維，惟目前使用的回收方法成本過於昂貴，為了解決此問題，有必要開發更高效能化之碳纖維回收方法，以提升此技術市場應用價值。若要能夠有效地將不同來源之碳纖維複合材料分解處理，在回收碳纖維處理前必須要搭配快速且有效率之非破壞性檢測技術，對碳纖維做快速檢測分類，不僅能配合不同溶劑之化學分解法，同時還可辨識出不易回收或是無回收價值之碳纖維。兆赫波具有低能量光子、高穿透和寬頻的特性，最有機會達到此檢測分類技術之目的，因此本實驗進行兆赫波碳纖維回收分類技術研究，藉由兆赫波光譜區分不同樹脂基碳纖維中環氧樹脂，以配合工研院研發低溫化學分解法得到可回收的樹脂與高品質長纖碳纖維。本實驗目標為使用兆赫波檢測技術進行碳纖維材料之品質鑑別，將兆赫波導入回收碳纖維複合材料的檢測技術領域，設計適用於回收線上檢測之兆赫波激發源，以加速兆赫波系統導入工業化碳纖維回收應用。

In order to achieve sustainable environmental development and reduce resource waste, the carbon fiber composite materials which have recycling value should no longer be regarded as waste, but should be reused. In recent years, many research institutions or manufacturers have invested in chemical decomposition carbon fiber recycling technology, using chemical solvents to separate the Epoxy matrix and the fibers, to obtain high-quality long carbon fibers. However, the current recycling methods are too expensive. In order to solve this problem, we must develop more efficient carbon fiber recycling methods, to enhance the application value of recycling technology in the market. To decompose carbon fiber composite materials from different sources effectively, the non-destructive detection technology is fast and efficient to get information before recycling carbon fiber. The rapid detection and classification technology can not only cooperate with the chemical decomposition method of different solvents, but also identify carbon fibers which are difficult to recycle or those have no recycling value. Terahertz has the unique characteristics of low-energy photons, high penetration and broadband. It seems to have best chance to achieve the goal of this detection and classification technology. Therefore, this experiment conducts the research of Terahertz spectrum to recycle and classify the carbon fiber, and distinguishes different Epoxy-based carbon fiber by Terahertz spectrum. Recyclable Epoxy and high-quality long-fiber carbon fiber are obtained by cooperating with the low-temperature chemical decomposition method developed by the Industrial Technology Research Institute. The goal of this experiment is to use Terahertz detection technology to identify the quality of carbon fiber materials, introduce Terahertz spectrum into the detection technology field of recycled carbon fiber composite materials, and design Terahertz wave excitation sources suitable for recycling line detection to accelerate industrial carbon fiber recycling application.

[1].Globus TR, Woolard DL, Khromova T, Crowe TW, Bykhovskaia M, Gelmont BL, et al. THz-Spectroscopy of Biological Molecules. Journal of Biological Physics 2003;29(2):89–100.
[2].Strait JH, George PA, Levendorf M, Blood-Forsythe M, Rana F, Park J. Measurements of the Carrier Dynamics and Terahertz Response of Oriented Germanium Nanowires using Optical-Pump Terahertz-Probe Spectroscopy. Nano Lett 2009;9(8):2967–72.
[3].Ajito K, Ueno Y. THz Chemical Imaging for Biological Applications. IEEE Transactions on Terahertz Science and Technology 2011;1(1):293–300.
[4].Wang S, Zhang X-C. Pulsed terahertz tomography. J Phys D: Appl Phys 2004;37(4):R1–R36.
[5].Chan WL, Deibel J, Mittleman DM. Imaging with terahertz radiation. Rep Prog Phys 2007;70(8):1325–1379.
[6].Mourou G, Stancampiano CV, Antonetti A, Orszag A. Picosecond microwave pulses generated with a subpicosecond laser‐driven semiconductor switch. Appl Phys Lett 1981;39(4):295–6.
[7].Mourou G, Stancampiano CV, Blumenthal D. Picosecond microwave pulse generation. Appl Phys Lett 1981;38(6):470–2.
[8].Heidemann R, Pfeiffer TH, Jäger D. Optoelectronically pulsed slot-line antennas. Electronics Letters 1983;19(9):316–7.
[9].Hu BB, Nuss MC. Imaging with terahertz waves. Opt Lett, OL 1995;20(16):1716–8.
[10].Auston DH, Cheung KP, Smith PR. Picosecond photoconducting Hertzian dipoles. Appl Phys Lett 1984;45(3):284–6.
[11].Rice A, Jin Y, Ma XF, Zhang X ‐C., Bliss D, Larkin J, et al. Terahertz optical rectification from 〈110〉 zinc‐blende crystals. Appl Phys Lett 1994;64(11):1324–6.
[12].Zhang X ‐C., Hu BB, Darrow JT, Auston DH. Generation of femtosecond electromagnetic pulses from semiconductor surfaces. Appl Phys Lett 1990;56(11):1011–3.
[13].van Exter M, Fattinger Ch, Grischkowsky D. High‐brightness terahertz beams characterized with an ultrafast detector. Appl Phys Lett 1989;55(4):337–9.
[14].Wu Q, Zhang X ‐C. Free‐space electro‐optic sampling of terahertz beams. Appl Phys Lett 1995;67(24):3523–5.
[15].Wu Q, Zhang X ‐C. Ultrafast electro‐optic field sensors. Appl Phys Lett 1996;68(12):1604–6.
[16].Wu Q, Hewitt TD, Zhang X ‐C. Two‐dimensional electro‐optic imaging of THz beams. Appl Phys Lett 1996;69(8):1026–8.
[17].Köhler R, Tredicucci A, Beltram F, Beere HE, Linfield EH, Davies AG, et al. Terahertz semiconductor-heterostructure laser. Nature 2002;417(6885):156–9.
[18].MarketsandMarkets. Carbon Fiber Market by Raw Material, Fiber Type, Product Type, Modulus, Application, End-use Industry & Geography | COVID-19 Impact Analysis | MarketsandMarkets [Internet]. 2019 [cited 2020 Dec 12];Available from: https://www.marketsandmarkets.com/Market-Reports/carbon-fiber-396.html
[19].Lee Y-S. Principles of Terahertz Science and Technology. Springer Science & Business Media; 2009.
[20].Strömberg M, Akhtar S, Gunnarsson K, Torre T, Russell C, Herthnek D, et al. Immobilization of oligonucleotide-functionalized magnetic nanobeads in DNA-coils studied by electron microscopy and atomic force microscopy. 2011.
[21].Dietz RJB, Gerhard M, Stanze D, Koch M, Sartorius B, Schell M. THz generation at 1.55 µm excitation: six-fold increase in THz conversion efficiency by separated photoconductive and trapping regions. Opt Express, OE 2011;19(27):25911–7.
[22].Dietz RJB, Globisch B, Gerhard M, Velauthapillai A, Stanze D, Roehle H, et al. 64 μW pulsed terahertz emission from growth optimized InGaAs/InAlAs heterostructures with separated photoconductive and trapping regions. Appl Phys Lett 2013;103(6):061103.
[23].Globisch B, Dietz RJB, Stanze D, Göbel T, Schell M. Carrier dynamics in Beryllium doped low-temperature-grown InGaAs/InAlAs. Appl Phys Lett 2014;104(17):172103.
[24].Dietz RJB, Globisch B, Roehle H, Stanze D, Göbel T, Schell M. Influence and adjustment of carrier lifetimes in InGaAs/InAlAs photoconductive pulsed terahertz detectors: 6 THz bandwidth and 90dB dynamic range. Opt Express, OE 2014;22(16):19411–22.
[25].Vieweg N, Rettich F, Deninger A, Roehle H, Dietz R, Göbel T, et al. Terahertz-time domain spectrometer with 90 dB peak dynamic range. J Infrared Milli Terahz Waves 2014;35(10):823–32.
[26].Chen CW, Lin YC, Chang CH, Yu P-C, Shieh JM, Pan CL. Frequency-dependent complex conductivities and dielectric responses of indium tin oxide thin films from the visible to the far-infrared. IEEE J Quantum Electron 2010;46(12):1746–54.