{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,1]],"date-time":"2025-10-01T15:56:30Z","timestamp":1759334190147,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2025,9,30]],"date-time":"2025-09-30T00:00:00Z","timestamp":1759190400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"China Petroleum Southwest Oil and Gas Field Company School Enterprise Joint Research Project","award":["20230302-33"],"award-info":[{"award-number":["20230302-33"]}]}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["Polymers"],"abstract":"<jats:p>To address critical limitations of ultra-low viscosity supercritical CO2 fracturing fluids, including excessive fluid loss and inadequate proppant transport capacity, a series of thickeners designed to significantly enhance CO2 viscosity were synthesized. Initially, FT-IR and 1H NMR characterization confirmed successful chemical reactions and incorporation of both solvation-enhancing and -thickening functional groups. Subsequently, dissolution and thickening performance were evaluated using a custom-designed high-pressure vessel featuring visual observation capability, in-line viscosity monitoring, and high-temperature operation. All thickener systems exhibited excellent solubility, with 5 wt% loading elevating CO2 viscosity to 3.68 mPa\u00b7s. Ultimately, molecular simulations performed in Materials Studio elucidated the mechanistic basis, electrostatic potential (ESP) mapping, cohesive energy density analysis, intermolecular interaction energy, and radial distribution function comparisons. These computational approaches revealed dissolution and thickening mechanisms of polymeric thickeners in CO2.<\/jats:p>","DOI":"10.3390\/polym17192640","type":"journal-article","created":{"date-parts":[[2025,9,30]],"date-time":"2025-09-30T10:54:48Z","timestamp":1759229688000},"page":"2640","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Synthesis of Linear Modified Siloxane-Based Thickeners and Study of Their Phase Behavior and Thickening Mechanism in Supercritical Carbon Dioxide"],"prefix":"10.3390","volume":"17","author":[{"given":"Pengfei","family":"Chen","sequence":"first","affiliation":[{"name":"Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gas Field Company, Chengdu 610500, China"},{"name":"Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province, Chengdu 610213, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ying","family":"Xiong","sequence":"additional","affiliation":[{"name":"Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gas Field Company, Chengdu 610500, China"},{"name":"Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province, Chengdu 610213, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daijun","family":"Du","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rui","family":"Jiang","sequence":"additional","affiliation":[{"name":"Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gas Field Company, Chengdu 610500, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jintao","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"126082","DOI":"10.1016\/j.molliq.2024.126082","article-title":"Molecular dynamics simulation of solvation behavior and thickening properties of modified siloxanes in supercritical carbon dioxide under different pressure and temperature","volume":"414","author":"Li","year":"2024","journal-title":"J. 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