{"id":5879,"date":"2026-03-02T15:44:42","date_gmt":"2026-03-02T14:44:42","guid":{"rendered":"https:\/\/www.woodresearch.sk\/cms\/?p=5879"},"modified":"2026-03-02T15:44:43","modified_gmt":"2026-03-02T14:44:43","slug":"the-effect-of-hardeners-on-the-dry-and-wet-bondline-strength-of-quebracho-tannin-resin-in-three-layer-plywood","status":"publish","type":"post","link":"https:\/\/www.woodresearch.sk\/cms\/the-effect-of-hardeners-on-the-dry-and-wet-bondline-strength-of-quebracho-tannin-resin-in-three-layer-plywood\/","title":{"rendered":"The Effect of Hardeners on the Dry and Wet Bondline Strength of Quebracho Tannin Resin in Three-Layer Plywood"},"content":{"rendered":"\n<div class=\"wp-block-pdf-viewer-block-standard\" style=\"text-align:left\"><div class=\"uploaded-pdf\"><a href=\"https:\/\/www.woodresearch.sk\/cms\/wp-content\/uploads\/2026\/03\/06_THE-EFFECT-OF-HARDENERS-ON-THE-DRY-AND-WET-BONDLINE-STRENGTH-OF-QUEBRACHO-TANNIN-RESIN-IN-THREE-LAYER-PLYWOOD.pdf\" data-width=\"\" data-height=\"\"><\/a><\/div><\/div>\n","protected":false},"excerpt":{"rendered":"<p>This study investigates the tensile shear strength of maple plywood bond lines bonded with quebracho tannin adhesive, modified using different hardeners: hexamine, paraformaldehyde, and methylene diphenyl diisocyanate. Adhesives were prepared by dispersing tannin powder in water, followed by the incorporation of each hardener, and applied to three-layer veneer panels cured under hot pressing. Bond line performance was evaluated under dry and wet conditions using tensile shear tests, with wet testing incorporating an accelerated cyclic-boil aging protocol. The results revealed that paraformaldehyde-modified tannin adhesives achieved the highest dry strength, 3.5 MPa, significantly exceeding the performance of both other tannin-based systems and synthetic adhesives. In contrast, under wet conditions, no significant differences were observed among tannin-based and synthetic adhesives, underscoring the strong influence of moisture on performance<\/p>\n","protected":false},"author":6,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5422],"tags":[924,5480,5482,5481],"release_year":[],"ppma_author":[5432,5433,5434,5435,5436,5437,5438,5439],"class_list":["post-5879","post","type-post","status-publish","format-standard","hentry","category-wood-research-volume-71-number-1-2026","tag-plywood","tag-quebracho-tannin","tag-wet-and-dry-condition","tag-wood-bond-line-strength"],"featured_image_src":null,"author_info":{"display_name":"Katar\u00edna Kalu\u017en\u00e1","author_link":"https:\/\/www.woodresearch.sk\/cms\/author\/kaluznavupc-sk\/"},"authors":[{"term_id":5432,"user_id":0,"is_guest":1,"slug":"umesh-lamichhane","display_name":"UMESH LAMICHHANE","avatar_url":"https:\/\/secure.gravatar.com\/avatar\/?s=96&d=mm&r=g","0":null,"1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""},{"term_id":5433,"user_id":0,"is_guest":1,"slug":"tasfia-hassan","display_name":"TASFIA HASSAN","avatar_url":"https:\/\/secure.gravatar.com\/avatar\/?s=96&d=mm&r=g","0":null,"1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""},{"term_id":5434,"user_id":0,"is_guest":1,"slug":"amir-mootab-saei","display_name":"AMIR MOOTAB SAEI","avatar_url":"https:\/\/secure.gravatar.com\/avatar\/?s=96&d=mm&r=g","0":null,"1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""},{"term_id":5435,"user_id":0,"is_guest":1,"slug":"fatemeh-rezaei","display_name":"FATEMEH REZAEI","avatar_url":"https:\/\/secure.gravatar.com\/avatar\/?s=96&d=mm&r=g","0":null,"1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""},{"term_id":5436,"user_id":0,"is_guest":1,"slug":"mostafa-mohammad-abadi","display_name":"MOSTAFA MOHAMMAD ABADI","avatar_url":"https:\/\/secure.gravatar.com\/avatar\/?s=96&d=mm&r=g","0":null,"1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""},{"term_id":5437,"user_id":0,"is_guest":1,"slug":"yunsang-kim","display_name":"YUNSANG KIM","avatar_url":"https:\/\/secure.gravatar.com\/avatar\/?s=96&d=mm&r=g","0":null,"1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""},{"term_id":5438,"user_id":0,"is_guest":1,"slug":"ali-dorieh","display_name":"ALI DORIEH","avatar_url":"https:\/\/secure.gravatar.com\/avatar\/?s=96&d=mm&r=g","0":null,"1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""},{"term_id":5439,"user_id":0,"is_guest":1,"slug":"sauro-bianchi","display_name":"SAURO BIANCHI","avatar_url":"https:\/\/secure.gravatar.com\/avatar\/?s=96&d=mm&r=g","0":null,"1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""}],"_links":{"self":[{"href":"https:\/\/www.woodresearch.sk\/cms\/wp-json\/wp\/v2\/posts\/5879","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.woodresearch.sk\/cms\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.woodresearch.sk\/cms\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.woodresearch.sk\/cms\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/www.woodresearch.sk\/cms\/wp-json\/wp\/v2\/comments?post=5879"}],"version-history":[{"count":1,"href":"https:\/\/www.woodresearch.sk\/cms\/wp-json\/wp\/v2\/posts\/5879\/revisions"}],"predecessor-version":[{"id":5881,"href":"https:\/\/www.woodresearch.sk\/cms\/wp-json\/wp\/v2\/posts\/5879\/revisions\/5881"}],"wp:attachment":[{"href":"https:\/\/www.woodresearch.sk\/cms\/wp-json\/wp\/v2\/media?parent=5879"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.woodresearch.sk\/cms\/wp-json\/wp\/v2\/categories?post=5879"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.woodresearch.sk\/cms\/wp-json\/wp\/v2\/tags?post=5879"},{"taxonomy":"release_year","embeddable":true,"href":"https:\/\/www.woodresearch.sk\/cms\/wp-json\/wp\/v2\/release_year?post=5879"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/www.woodresearch.sk\/cms\/wp-json\/wp\/v2\/ppma_author?post=5879"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}