{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T19:18:00Z","timestamp":1792091880359,"version":"4.4.0"},"reference-count":51,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2021,11,25]],"date-time":"2021-11-25T00:00:00Z","timestamp":1637798400000},"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":["51991354"],"award-info":[{"award-number":["51991354"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>The compound 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA) is an eco-friendly water treatment agent possessing flame-retardant phosphorus element and multi-carboxylic acid groups in its molecular structure. In the present work, PBTCA is employed as a finishing agent to improve the flame retardancy of the wool fabrics by the pad-dry-cure technique. The treated wool (10.2% weight gain) by 100 g\/L of PBTCA showed an increased flame retardancy with a limiting oxygen index value (LOI) of 44% with a minimum char length of 40 mm. Importantly, the treated wool can self-extinguish after 30 washing cycles. The PBTCA-treated wool exhibited better stability with obviously increased char residue of 39.7% and 28.7% at 600 \u00b0C, while only 25.9% and 13.2% were measured for the control wool in nitrogen and air atmosphere, respectively. In addition, the high thermal stability of the treated wool with astonishing char-forming ability is confirmed by the SEM images of the wool after the isothermal heating treatment at different temperatures. Finally, a two-stage flame-retarding mechanism of enhanced crosslinking and char formability of PBTCA-treated wool is proposed and analyzed by infrared spectroscopy (TG-FTIR) and thermal (DSC and TGA) results of the pyrolytic volatiles of the treated wool.<\/jats:p>","DOI":"10.3390\/polym13234111","type":"journal-article","created":{"date-parts":[[2021,12,1]],"date-time":"2021-12-01T02:34:05Z","timestamp":1638326045000},"page":"4111","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Flame Retardancy and Thermal Behavior of Wool Fabric Treated with a Phosphorus-Containing Polycarboxylic Acid"],"prefix":"10.3390","volume":"13","author":[{"given":"Huaifang","family":"Wang","sequence":"first","affiliation":[{"name":"College of Textile and Clothing, Institute of Functional Textiles and Advanced Materials, College of Textile and Clothing, State Key Laboratory of Bio-Fibers and Eco-Textiles, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shengnan","family":"Guo","sequence":"additional","affiliation":[{"name":"College of Textile and Clothing, Institute of Functional Textiles and Advanced Materials, College of Textile and Clothing, State Key Laboratory of Bio-Fibers and Eco-Textiles, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chuanjie","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Textile and Clothing, Institute of Functional Textiles and Advanced Materials, College of Textile and Clothing, State Key Laboratory of Bio-Fibers and Eco-Textiles, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhichuang","family":"Qi","sequence":"additional","affiliation":[{"name":"College of Textile and Clothing, Institute of Functional Textiles and Advanced Materials, College of Textile and Clothing, State Key Laboratory of Bio-Fibers and Eco-Textiles, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lianfeng","family":"Li","sequence":"additional","affiliation":[{"name":"Shandong Ruyi Wool Textile Garment Group Co. Ltd., Jining 272073, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ping","family":"Zhu","sequence":"additional","affiliation":[{"name":"College of Textile and Clothing, Institute of Functional Textiles and Advanced Materials, College of Textile and Clothing, State Key Laboratory of Bio-Fibers and Eco-Textiles, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,25]]},"reference":[{"key":"ref_1","first-page":"108","article-title":"The structure and properties of wool and hair fibres","volume":"Volume 2","author":"Eichhorn","year":"2009","journal-title":"Handbook of Textile Fibre Structure"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1111\/j.1478-4408.1986.tb03745.x","article-title":"Flame-retardant finishing of textiles","volume":"16","author":"Horrocks","year":"1986","journal-title":"Rev. Prog. 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