{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T01:22:17Z","timestamp":1789435337751,"version":"build-2803163510"},"reference-count":54,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,10,18]],"date-time":"2018-10-18T00:00:00Z","timestamp":1539820800000},"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":["No.51704322, No. U1562101"],"award-info":[{"award-number":["No.51704322, No. U1562101"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007129","name":"Natural Science Foundation of Shandong Province","doi-asserted-by":"publisher","award":["No. ZR2017QEE011"],"award-info":[{"award-number":["No. ZR2017QEE011"]}],"id":[{"id":"10.13039\/501100007129","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the 13th Five-year Plan National Key project","award":["2017ZX05005005-006"],"award-info":[{"award-number":["2017ZX05005005-006"]}]},{"DOI":"10.13039\/501100018621","name":"Program for Changjiang Scholars and Innovative Research Team in University","doi-asserted-by":"publisher","award":["IRT_14R58"],"award-info":[{"award-number":["IRT_14R58"]}],"id":[{"id":"10.13039\/501100018621","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the Fundamental Research Funds for the Central Universities","award":["No.18CX02099A"],"award-info":[{"award-number":["No.18CX02099A"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>In order to mitigate the loss circulation of oil-based drilling fluids (OBDFs), an oil-absorbent polymer (OAP) composed by methylmethacrylate (MMA), butyl acrylate (BA), and hexadecyl methacrylate (HMA) was synthesized by suspension polymerization and characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and scanning electronic microscopy (SEM). The oil-absorptive capacity of OAP under different solvents was measured as the function of temperature and time. The effect of the OAP on the rheological and filtration properties of OBDFs was initially evaluated, and then the sealing property of OAP particles as lost circulation materials (LCMs) was examined by a high-temperature and high-pressure (HTHP) filtration test, a sand bed filtration test, a permeable plugging test, and a fracture sealing testing. The test results indicated that the addition of OAP had relatively little influence on the rheological properties of OBDF at content lower than 1.5 w\/v % but increased the fluid viscosity remarkably at content higher than 3 w\/v %. It could reduce the HTHP filtration and improve the sealing capacity of OBDF significantly. In the sealing treatment, after addition into the OBDF, the OAP particles could absorb oil accompanied with volume enlargement, which led to the increase of the fluid viscosity and slowing down of the fluid loss speed. The swelled and deformable OAP particles could be squeezed into the micro-fractures with self-adoption and seal the loss channel. More important, fluid loss was dramatically reduced when OAP particles were combined with other conventional LCMs by a synergistic effect.<\/jats:p>","DOI":"10.3390\/ma11102020","type":"journal-article","created":{"date-parts":[[2018,10,18]],"date-time":"2018-10-18T10:55:41Z","timestamp":1539860141000},"page":"2020","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":52,"title":["Mitigation of Lost Circulation in Oil-Based Drilling Fluids Using Oil Absorbent Polymers"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8962-4770","authenticated-orcid":false,"given":"Hanyi","family":"Zhong","sequence":"first","affiliation":[{"name":"School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guangcheng","family":"Shen","sequence":"additional","affiliation":[{"name":"School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peng","family":"Yang","sequence":"additional","affiliation":[{"name":"GWDC Engineering Research Institute, Panjin 124010, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhengsong","family":"Qiu","sequence":"additional","affiliation":[{"name":"School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junbin","family":"Jin","sequence":"additional","affiliation":[{"name":"SINOPEC Research Institute of Petroleum Engineering, Beijing 100101, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaodong","family":"Xing","sequence":"additional","affiliation":[{"name":"China Petroleum Engineering &amp; Construction CORP, North China Company, Renqiu 062552, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"375","DOI":"10.1016\/j.jngse.2017.08.003","article-title":"Testing conditions make a difference when testing LCM","volume":"46","author":"Jeennakorn","year":"2018","journal-title":"J. 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