{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T03:18:53Z","timestamp":1790651933636,"version":"4.1.0"},"reference-count":44,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,10,2]],"date-time":"2019-10-02T00:00:00Z","timestamp":1569974400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["31570552"],"award-info":[{"award-number":["31570552"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004608","name":"Natural Science Foundation of Jiangsu Province","doi-asserted-by":"publisher","award":["BK20180774"],"award-info":[{"award-number":["BK20180774"]}],"id":[{"id":"10.13039\/501100004608","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>To evaluate the effects of phenol formaldehyde (PF) resin modification on wood cell walls, Masson pine (Pinus massoniana Lamb.) wood was impregnated with PF resin at the concentrations of 15%, 20%, 25%, and 30%, respectively. The penetration degree of PF resin into wood tracheids was quantitatively determined using confocal laser scanning microscopy (CLSM). The micromechanical properties of the control and PF-modified wood cell walls were then analyzed by the method of quasi-static nanoindentation and dynamic modulus mapping techniques. Results indicated that PF resin with low molecular weight can penetrate deeply into the wood tissues and even into the cell walls. However, the penetration degree decreased accompanying with the increase of penetration depth in wood. Both the quasi-static and dynamic mechanics of wood cell walls increased significantly after modification by the PF resin at the concentration less than 20%. The cell-wall mechanics maintained stable and even decreased as the resin concentration was increased above 20%, resulting from the increasing bulking effects such as the decreased crystallinity degree of cellulose. Furthermore, the mechanics of cell walls in the inner layer was lower than that in the outer layer of PF-modified wood.<\/jats:p>","DOI":"10.3390\/nano9101409","type":"journal-article","created":{"date-parts":[[2019,10,3]],"date-time":"2019-10-03T03:41:27Z","timestamp":1570074087000},"page":"1409","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Effect of Phenol Formaldehyde Resin Penetration on the Quasi-Static and Dynamic Mechanics of Wood Cell Walls Using Nanoindentation"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3972-3073","authenticated-orcid":false,"given":"Xinzhou","family":"Wang","sequence":"first","affiliation":[{"name":"College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuanzong","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuqin","family":"Xie","sequence":"additional","affiliation":[{"name":"Dehua Tubao New Decoration Material Co., Ltd., Huzhou 313200, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhurun","family":"Yuan","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shaoxiang","family":"Cai","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanjun","family":"Li","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,2]]},"reference":[{"key":"ref_1","unstructured":"Dekker, M. (1989). Wood Adhesives: Chemistry and Technology, CRC Press."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Pizzi, A. (2015). Synthetic Adhesives for Wood Panels: Chemistry and Technology. Progress in Adhesion and Adhesives, John Wiley & Sons, Inc.","DOI":"10.1002\/9781119162346.ch4"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1186\/s10086-019-1799-z","article-title":"Mechanical and physical properties of cross-laminated timber made from acacia mangium wood as function of adhesive types","volume":"65","author":"Yusof","year":"2019","journal-title":"J. Wood Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"895","DOI":"10.3832\/ifor2380-010","article-title":"Wood modification technologies\u2014A review","volume":"10","author":"Sandberg","year":"2017","journal-title":"iForest"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"956","DOI":"10.1016\/j.conbuildmat.2017.08.035","article-title":"Evaluating the mechanical and fire-resistance properties of modified fast-growing Chinese fir timber with boric-phenol-formaldehyde resin","volume":"154","author":"Yue","year":"2017","journal-title":"Constr. Build. Mater."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"3565","DOI":"10.1177\/0021998312467386","article-title":"Physical and thermal properties of microwave-dried wood lumber impregnated with phenol formaldehyde resin","volume":"47","author":"Khalil","year":"2013","journal-title":"J. Compos. Mater."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Hill, C.A.S. (2006). Wood Modification: Chemical, Thermal and other Processes, Wiley.","DOI":"10.1002\/0470021748"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1007\/s00226-009-0253-6","article-title":"Phenol-formaldehyde impregnation of densified wood for improved dimensional stability","volume":"44","author":"Gabrielli","year":"2010","journal-title":"Wood Sci. Technol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1016\/S0960-8524(99)00167-4","article-title":"Chemical modification of wood with thermosetting resin: Effect on dimensional stability and strength property","volume":"73","author":"Deka","year":"2000","journal-title":"Bioresour. Technol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"259","DOI":"10.1007\/s00107-017-1180-0","article-title":"Modification of wood with formulations of phenolic resin and iron-tannin-complexes to improve material properties and expand colour variety","volume":"76","author":"Kielmann","year":"2017","journal-title":"Eur. J. Wood Wood Prod."},{"key":"ref_11","first-page":"691","article-title":"Mode of action of brown rot decay resistance of acetylated wood: Resistance to fenton\u2019s reagent","volume":"70","author":"Hosseinpourpia","year":"2016","journal-title":"Wood Sci. Technol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1007\/s00226-018-1058-2","article-title":"Penetration depth of phenol-formaldehyde (PF) resin into beech wood studied by light microscopy","volume":"53","author":"Biziks","year":"2019","journal-title":"Wood Sci. Technol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1007\/s002260050103","article-title":"Measurement of cell wall penetration in wood of water based chemicals using SEM\/EDS and STEM\/EDS technique","volume":"33","author":"Lindberg","year":"1999","journal-title":"Wood Sci. Technol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"6584","DOI":"10.1021\/am5087598","article-title":"Synchrotron-based X-ray fluorescence microscopy in conjunctionwith nanoindentation to study molecular-scale interactions of phenol-formaldehyde in wood cell walls","volume":"7","author":"Jakes","year":"2015","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"349","DOI":"10.1007\/s00226-003-0176-6","article-title":"The modification of wood by treatment with low molecular weight phenol-formaldehyde resin: A properties enhancement with neutralized phenolic-resin and resin penetration into wood cell walls","volume":"37","author":"Furuno","year":"2004","journal-title":"Wood Sci. Technol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"76318","DOI":"10.1039\/C6RA13159J","article-title":"In situ identification of the molecular-scale interactions of phenol-formaldehyde resin and wood cell walls using infrared nanospectroscopy","volume":"6","author":"Wang","year":"2016","journal-title":"RSC Adv."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1345","DOI":"10.1016\/j.compositesa.2004.04.002","article-title":"The significance of the elastic modulus of wood cell walls obtained from nanoindentation measurements","volume":"35","author":"Gindl","year":"2004","journal-title":"Compos. Part A"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Wu, Y., Sun, Y., Yang, F., Zhang, H., and Wang, Y. (2019). The implication of benzene-ethanol extractive on mechanical properties of waterborne coating and wood cell wall by nanoindentation. Coatings, 9.","DOI":"10.3390\/coatings9070449"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"5529","DOI":"10.15376\/biores.9.3.5529-5541","article-title":"Micromechanical properties of the interphase in cellulose nanofiber-reinforced phenol formaldehyde bondlines","volume":"9","author":"Liu","year":"2014","journal-title":"BioResources"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Wu, Y., Wu, J., Wang, S., Feng, X., Chen, H., Tang, Q., and Zhang, H. (2019). Measurement of mechanical properties of multilayer waterborne coatings on wood by nanoindentation. Holzforschung.","DOI":"10.1515\/hf-2018-0193"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1229","DOI":"10.1080\/07373930903266726","article-title":"Effects of time and temperature on the viscoelastic properties of Chinese Fir wood","volume":"27","author":"Jiang","year":"2009","journal-title":"Dry. Technol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"35505","DOI":"10.1103\/PhysRevLett.100.035505","article-title":"Investigation of interface properties by nanoscale elastic modulus mapping","volume":"100","author":"Shilo","year":"2008","journal-title":"Phys. Rev. Lett."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"118","DOI":"10.1016\/j.msea.2014.08.036","article-title":"Comparison of nanoindentation techniques for local mechanical quantification of aluminium alloy","volume":"618","year":"2014","journal-title":"Mater. Sci. Eng. A"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"39","DOI":"10.14311\/AP.2015.55.0039","article-title":"Microstructure description and micromechanical properties of spruce wood","volume":"55","year":"2015","journal-title":"Acta Polytech."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"549","DOI":"10.1007\/s10853-017-1185-4","article-title":"Micromechanical properties of wood cell wall and interface compound middle lamella using quasi-static nanoindentation and dynamic modulus mapping","volume":"53","author":"Qin","year":"2018","journal-title":"J. Mater. Sci."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"786","DOI":"10.1177\/004051755902901003","article-title":"An empirical method for estimating the degree of crystallinity of native cellulose using X-ray diffractometer","volume":"29","author":"Segal","year":"1959","journal-title":"Text. Res. J."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1564","DOI":"10.1557\/JMR.1992.1564","article-title":"An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments","volume":"7","author":"Oliver","year":"1992","journal-title":"J. Mater. Res."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"2408","DOI":"10.1063\/1.1149769","article-title":"Nanoindentation and contact stiffness measurement using force modulation with a capacitive load-displacement transducer","volume":"70","author":"Asif","year":"1999","journal-title":"Rev. Sci. Instrum."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1192","DOI":"10.1063\/1.1380218","article-title":"Quantitative imaging of nanoscale mechanical properties using hybrid nanoindentation and force modulation","volume":"90","author":"Asif","year":"2001","journal-title":"J. Appl. Phys."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1007\/s00107-014-0858-9","article-title":"MALDI-TOF MS analysis of the acceleration of the curing of phenol-formaldehyde (PF) resins induced by propylene carbonate","volume":"73","author":"Zhang","year":"2015","journal-title":"Eur. J. Wood Wood Prod."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Wang, X., Chen, X., Xie, X., Cai, S., Yuan, Z., and Li, Y. (2019). Multi-scale evaluation of the effect of phenol formaldehyde resin impregnation on the dimensional stability and mechanical properties of Pinus massoniana Lamb. Forests, 10.","DOI":"10.3390\/f10080646"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"389","DOI":"10.1007\/s10086-005-0787-7","article-title":"Compressive deformation of wood impregnated with low molecular weight phenol formaldehyde (PF) resin V: Effects of steam pretreatment","volume":"52","author":"Shams","year":"2006","journal-title":"J. Wood Sci."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Cai, M., Fu, Z., Cai, Y., Li, Z., Xu, C., Xu, C., and Li, S. (2018). Effect of impregnation with maltodextrin and 1,3-dimethylol-4,5-dihydroxyethyleneurea on Poplar wood. Forests, 9.","DOI":"10.3390\/f9110676"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1076","DOI":"10.15376\/biores.8.1.1076-1088","article-title":"The mechanical strength change of wood modified with DMDHEU","volume":"8","author":"Yuan","year":"2013","journal-title":"BioResources"},{"key":"ref_35","first-page":"1404","article-title":"Analysis of the microfibrilla angles & crystallinity index of daemonorops margaritae with X-ray diffractometry and the effects of \u03b3-ray irradiation","volume":"30","author":"Jiang","year":"2010","journal-title":"Spectrosc. Spectr. Anal."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"124","DOI":"10.1007\/BF00780560","article-title":"Allomorphs of native crystalline cellulose I evaluated by two equatoriald-spacings","volume":"47","author":"Wada","year":"2001","journal-title":"J. Wood Sci."},{"key":"ref_37","first-page":"238","article-title":"Characterization of phenol-formaldehyde prepolymer resins by in line FT-IR spectroscopy","volume":"52","author":"Krajnc","year":"2015","journal-title":"Acta Chim. Slov."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1185","DOI":"10.1007\/s00226-015-0750-8","article-title":"X-ray computed tomography of wood-adhesive bondlines: Attenuation and phase-contrast effects","volume":"49","author":"Paris","year":"2015","journal-title":"Wood Sci. Technol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1007\/s00226-003-0221-5","article-title":"Curing kinetics of phenol formaldehyde resin and wood-resin interactions in the presence of wood substrates","volume":"38","author":"He","year":"2004","journal-title":"Wood Sci. Technol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"2867","DOI":"10.1016\/j.biortech.2009.10.074","article-title":"Evaluation of elastic modulus and hardness of crop stalks cell walls by nano-indentation","volume":"101","author":"Wu","year":"2010","journal-title":"Bioresour. Technol."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"268","DOI":"10.1007\/BF00350273","article-title":"The anisotropic elasticity of the plant cell wall","volume":"2","author":"Cave","year":"1968","journal-title":"Wood Sci. Technol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1003","DOI":"10.1007\/s00226-011-0458-3","article-title":"Viscoelasticproperties of wood materials characterized by nanoindentation experiments","volume":"46","author":"Zhang","year":"2012","journal-title":"Wood Sci. Technol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"909","DOI":"10.1515\/hf-2014-0112","article-title":"Quasi-static and dynamic nanoindentation to determine the influence of thermal treatment on the mechanical properties of bamboo cell walls","volume":"69","author":"Li","year":"2015","journal-title":"Holzforschung"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1016\/S0143-7496(97)00048-1","article-title":"On the occurrence of network interpenetration in the wood-isocyanate adhesive interphase","volume":"18","author":"Frazier","year":"1998","journal-title":"Int. J. Adhes. Adhes."}],"container-title":["Nanomaterials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-4991\/9\/10\/1409\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:27:12Z","timestamp":1760189232000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-4991\/9\/10\/1409"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,10,2]]},"references-count":44,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2019,10]]}},"alternative-id":["nano9101409"],"URL":"https:\/\/doi.org\/10.3390\/nano9101409","relation":{},"ISSN":["2079-4991"],"issn-type":[{"value":"2079-4991","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,10,2]]}}}