{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T01:37:57Z","timestamp":1792805877072,"version":"4.5.0"},"reference-count":58,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2023,9,28]],"date-time":"2023-09-28T00:00:00Z","timestamp":1695859200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Clemson University","id":[{"id":"https:\/\/ror.org\/037s24f05","id-type":"ROR","asserted-by":"crossref"}]},{"name":"Daikin America"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Two new fluorine-containing diamine monomers were designed with the goal of reducing charge transfer complex (CTC) interactions between neighboring chains in polyimides (i.e., high transparency\/low color) while hopefully maintaining the well-known thermal stability and flexibility generally associated with polyimides. The proposed diamines have been prepared through (1) the functionalization of 1,3-bis[(pentafluorobenzyl)oxy]benzene with 4-aminophenol and (2) the addition of 2-chloro-5-nitrobenzotrifluoride to 4,4\u2032-bicyclohexanol followed by reduction of the resulting dinitro compound. The new compounds have been characterized by multinuclear NMR and IR spectroscopy and high-resolution liquid chromatography-mass spectrometry as well as single-crystal X-ray diffraction on the new diamine prepared from 4,4\u2032-bicyclohexanol. Not only was the structure of the proposed new diamine confirmed, but another interesting example of hydrogen bonding between an N-H proton and the \u03c0-system of an aromatic ring was observed and documented. Initial polymerizations have been carried out via the two-step imidization process.<\/jats:p>","DOI":"10.3390\/molecules28196855","type":"journal-article","created":{"date-parts":[[2023,9,29]],"date-time":"2023-09-29T07:42:08Z","timestamp":1695973328000},"page":"6855","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["New Fluorine-Containing Diamine Monomers for Potentially Improved Polyimides"],"prefix":"10.3390","volume":"28","author":[{"given":"Cassandra J.","family":"Hager","sequence":"first","affiliation":[{"name":"Advanced Materials Research Laboratory, Department of Chemistry, Clemson University, 91 Technology Drive, Anderson, SC 29625, USA"},{"name":"Hunter Laboratory, Department of Chemistry, Clemson University, 211 S. Palmetto Blvd., Clemson, SC 29634, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7773-8797","authenticated-orcid":false,"given":"Colin D.","family":"McMillen","sequence":"additional","affiliation":[{"name":"Hunter Laboratory, Department of Chemistry, Clemson University, 211 S. Palmetto Blvd., Clemson, SC 29634, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rakesh","family":"Sachdeva","sequence":"additional","affiliation":[{"name":"Hunter Laboratory, Department of Chemistry, Clemson University, 211 S. Palmetto Blvd., Clemson, SC 29634, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arthur W.","family":"Martin","sequence":"additional","affiliation":[{"name":"R & D Technical Center, Daikin America, Inc., 2749 Hwy 20 West, Suite A, Decatur, AL 35601, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1479-1897","authenticated-orcid":false,"given":"Joseph S.","family":"Thrasher","sequence":"additional","affiliation":[{"name":"Advanced Materials Research Laboratory, Department of Chemistry, Clemson University, 91 Technology Drive, Anderson, SC 29625, USA"},{"name":"Hunter Laboratory, Department of Chemistry, Clemson University, 211 S. Palmetto Blvd., Clemson, SC 29634, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,28]]},"reference":[{"key":"ref_1","unstructured":"(2020, October 03). Glass Transition Temperatures. 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