|
|
|
|
|
|
| Influence of Thermal Modification on Poplar Strength Class by Fourier Infrared Spectroscopy Analysis |
| YUE Kong, LU Dong, SONG Xue-song |
College of Civil Engineering, Nanjing Tech University, Nanjing 211800, China
|
|
|
|
|
Abstract The study was performed to evaluate the effects of thermal modification on the mechanical properties, optimize the modification temperature based on strength class, and provide a basis for the rational application of thermally modified wood in buildings. In this study, a total of 560 poplar wood specimens were tested to determine the effects of thermal modification between 160 and 210 ℃ on mechanical properties, such as bending strength (fm), parallel-to-grain tensile strength along the grain (ft, 0), perpendicular-to-grain tangential (ft, T, 90) and radial tensile strength (ft, R, 90), parallel-to-grain compressive strength (fc, 0), parallel-to-grain tangential (fv, T) and radial shear strength (fv, R), and modulus of elasticity (E0). The Fourier transform infrared spectroscopy was used to analyze the changes in chemical components of thermally modified wood at different temperature levels. The optimization temperature of thermal modification based on strength class was put forward. The results showed that the hemicellulose within wood had the lowest heat resistance under high-temperature condition and was first degraded by thermal exposure followed by acceleration at ≥190 ℃. The thermal resistance of cellulose was relatively higher, which was slightly degraded at the higher temperature, and mainly occurred in the amorphous region, increasing the orderly arrangement of microfibril. It was shown that thermal modification had an obvious adverse effects on fm, ft, 0, ft, 90 and fv of poplar wood. At room temperature, fm, ft, 0, ft, T, 90, ft, R, 90, fv, T and fv, R were determined as 67.0, 86.2, 5.8, 8.9, 7.7 and 6.7 MPa, respectively. At lower temperatures, the chemical components of wood degraded slightly, and the mechanical properties of thermally modified poplar wood specimens decreased slowly. These parameters decreased to 53.5, 78.9, 4.0, 4.8, 6.0 and 5.4 MPa at 180 ℃, respectively. When the temperature was ≥190 ℃, severe pyrolysis occurred to the main chemical components, resulting in the rapid reduction of mechanical properties. At 210 ℃, these parameters represented 44.5%, 56.1%, 43.1%, 29.2%, 34.5% and 26.7% of the values at normal temperature, respectively. fc, 0 and E0 of thermally modified poplar wood increased as the temperature increased from 160 to 180 ℃, then decreased in the temperature range between 190 and 210 ℃. fc, 0 and E0 were 41.4 and 8 568 MPa at 20 ℃, respectively. In the temperature range between 160 and 180 ℃, the crystallization of cellulose increased, leading to the increase of the two parameters. At temperature of 180 ℃, fc, 0 and E0 were 30.7% and 12.8% higher than those at room temperature, respectively. The pyrolysis of cellulose increased with the temperature, resulting in the two values decreasing continuously until they achieved 45.0 and 8 104 MPa at 210 ℃, respectively. The untreated poplar wood cannot be used as a structural material, because E0 does not meet the requirements of the minimum strength class D18 according to European standard BS EN 338. The E0 of the modified wood specimen between 160 and 170 ℃ was higher than that of the untreated, but it was still lower than that specified by the minimum strength grade D18. After that, E0 increased with increasing temperature, and the modified poplar wood reached strength class D18 at 180 ℃. At temperatures between 190 and 200 ℃, the E0 of thermally modified wood specimens was higher than the corresponding value of strength class D18, but they still cannot be used as loading-bearing materials due to the excessive reduction of fv, R. The study can provide a basis for the rational application of thermal modification technology and low-quality fast-growing wood in engineering structures.
|
|
Received: 2022-01-24
Accepted: 2022-05-23
|
|
|
|
[1] Cademartori P, Santos P, Serrano L, et al. Industrial Crops and Products, 2013, 45: 360.
[2] YUE Kong, SONG Xu-lei, JIAO Xue-kai, et al(岳 孔, 宋旭磊, 焦学凯, 等). Scientia Silvae Sinicae(林业科学), 2020, 56(4): 128.
[3] Yue K, Song X L, Jiao X K, et al. Wood and Fiber Science, 2020, 52(2): 152.
[4] Yue K, Wu J H, Wang F, et al. Journal of Materials in Civil Engineering, 2022, 34(2): 04021434.
[5] YUE Kong, LU Dong, HU Wen-jie, et al(岳 孔, 陆 栋, 胡文杰, 等). Scientia Silvae Sinicae(林业科学), 2022, 58(1): 118.
[6] YUE Kong, CHENG Xiu-cai, JIA Chong, et al(岳 孔, 程秀才, 贾 翀, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2019, 39(10): 3179.
[7] YUE Kong, LU Dong, DAI Chang-lu, et al(岳 孔, 陆 栋, 戴长路, 等). Journal of Huazhong University of Science and Technology·Natural Science Edition(华中科技大学学报·自然科学版), 2021, 49(4): 86.
[8] Santos J A. Wood Science and Technology，2000, 34(1): 39.
[9] Esteves B, Graça J, Pereira H. Holzforschung, 2008, 62(3): 344.
[10] Mirzaei G, Mohebby B, Ebrahimi G. Construction and Building Materials, 2017, 135: 386.
[11] Mirzaei G, Mohebby B, Ebrahimi G. Wood Materials Science & Engineering, 2018, 13(1): 36.
[12] Herrera R, Arrese A, de Hoyos-Martinez P, et al. Construction and Building Materials, 2018, 172: 233.
[13] Colom X, Carrillo F, Nogués F, et al. Polymer Degradation and Stability, 2003, 80(3): 543
[14] Hakkou M, Pétrissans M, Zoulalian A, et al. Polymer Degradation and Stability, 2005, 89(1): 1.
[15] Mtr B, Hirai N, Sobue N. Journal of Wood Science, 2000, 46(6): 431.
[16] Tarmian A, Mastouri A. iForest-Biogeosciences and Forestry, 2019, 12(1): 92
[17] Zhang N, Xu M, Cai L. Scientific Reports, 2019, 9(1): 982.
|
| [1] |
GUO Ya-fei1, CAO Qiang1, YE Lei-lei1, ZHANG Cheng-yuan1, KOU Ren-bo1, WANG Jun-mei1, GUO Mei1, 2*. Double Index Sequence Analysis of FTIR and Anti-Inflammatory Spectrum Effect Relationship of Rheum Tanguticum[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2024, 44(01): 188-196. |
| [2] |
TIAN Ze-qi1, WANG Zhi-yong1, YAO Jian-guo1, GUO Xu1, LI Hong-dou1, GUO Wen-mu1, SHI Zhi-xiang2, ZHAO Cun-liang1, LIU Bang-jun1*. Quantitative FTIR Characterization of Chemical Structures of Highly Metamorphic Coals in a Magma Contact Zone[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(09): 2747-2754. |
| [3] |
ZHANG Xiao-xu1, LIN Xiao-xian3, ZHANG Dan2, ZHANG Qi1, YIN Xue-feng2, YIN Jia-lu3, 4, ZHANG Wei-yue4, LI Yi-xuan1, WANG Dong-liang3, 4*, SUN Ya-nan1*. Study on the Analysis of the Relationship Between Functional Factors and Intestinal Flora in Freshly Stewed Bird's Nest Based on Fourier Transform Infrared Spectroscopy[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(08): 2452-2457. |
| [4] |
WANG Yu-hao1, 2, LIU Jian-guo1, 2, XU Liang2*, DENG Ya-song2, SHEN Xian-chun2, SUN Yong-feng2, XU Han-yang2. Application of Principal Component Analysis in Processing of Time-Resolved Infrared Spectra of Greenhouse Gases[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(07): 2313-2318. |
| [5] |
SU Ling1, 2, BU Ya-ping1, 2, LI Yuan-yuan2, WANG Qi1, 2*. Study on the Prediction Method of Pleurotus Ostreatus Protein and
Polysaccharide Content Based on Fourier Transform Infrared
Spectroscopy[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(04): 1262-1267. |
| [6] |
ZHOU Ao1, 2, YUE Zheng-bo1, 2, LIU A-zuan1, 2, GAO Yi-jun3, WANG Shao-ping3, CHUAI Xin3, DENG Rui1, WANG Jin1, 2*. Spectral Analysis of Extracellular Polymers During Iron Dissimilar
Reduction by Salt-Tolerant Shewanella Aquimarina[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(04): 1320-1328. |
| [7] |
FENG Yu, ZHANG Yun-hong*. Rapid ATR-FTIR Principal Component Analysis of Commercial Milk[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(03): 838-841. |
| [8] |
ZHANG Yan1, 2, WANG Hui-le1, LIU Zhong2, ZHAO Hui-fang1, YU Ying-ying1, LI Jing1, TONG Xin1. Spectral Analysis of Liquefaction Residue From Corn Stalk Polyhydric
Alcohols Liquefaction at Ambient Pressure[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(03): 911-916. |
| [9] |
QIAO Lu1, LIU Rui-na1, ZHANG Rui1, ZHAO Bo-yu1, HAN Pan-pan1, 2, ZHOU Chun-ya1, 3, ZHANG Yu-qing1, 4, DONG Cheng-ming1*. Analysis of Spectral Characteristics of Soil Under Different Continuous Cropping of Rehmannia Glutinosa Based on Infrared Spectroscopy[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(02): 541-548. |
| [10] |
CHEN Yong1, 2, GUO Yun-zhu1, WANG Wei3*, WU Xiao-hong1, 2*, JIA Hong-wen4, WU Bin4. Clustering Analysis of FTIR Spectra Using Fuzzy K-Harmonic-Kohonen Clustering Network[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(01): 268-272. |
| [11] |
HU Yun-you1, 2, XU Liang1*, XU Han-yang1, SHEN Xian-chun1, SUN Yong-feng1, XU Huan-yao1, 2, DENG Ya-song1, 2, LIU Jian-guo1, LIU Wen-qing1. Adaptive Matched Filter Detection for Leakage Gas Based on Multi-Frame Background[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(10): 3307-3313. |
| [12] |
LÜ Dan-dan，WEI Hui-ru，ZHANG Wei-gang*. Study on Near-Infrared Spectroscopy and Hydrophobicity of PDMS
Modified Epoxy Resin/Sm2O3 Composite Coating[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(09): 2855-2861. |
| [13] |
JING Jian-yuan, YUAN Liang, ZHANG Shui-qin, LI Yan-ting, ZHAO Bing-qiang*. Multispectral Structural Characterization of Humic Acid-Enhanced Urea[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(08): 2610-2615. |
| [14] |
LI Shu-jie1, LIU Jie1, DENG Zi-ang1, OU Quan-hong1, SHI You-ming2, LIU Gang1*. Study of Germinated Rice Seeds by FTIR Spectroscopy Combined With Curve Fitting[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(06): 1832-1840. |
| [15] |
ZHA Ling-ling1, 2, 3, WANG Wei2*, XIE Yu1, SHAN Chang-gong2, ZENG Xiang-yu2, SUN You-wen2, YIN Hao2, HU Qi-hou2. Observation of Variations of Ambient CO2 Using Portable FTIR
Spectrometer[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(04): 1036-1043. |
|
|
|
|
