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Abstract Linear polyphosphonates with the generic formula –[P(Ph)(X)OR′O]n– (X = S or Se) have been synthesized by polycondensations of P(Ph)(NEt2)2and a diol (HOR′OH = 1,4‐cyclohexanedimethanol, 1,4‐benzenedimethanol, tetraethylene glycol, or 1,12‐dodecanediol) followed by reaction with a chalcogen. Random copolymers have been synthesized by polycondensations of P(Ph)(NEt2)2and mixture of two of the diols in a 2:1:1 mol ratio followed by reaction with a chalcogen. Block copolymers with the generic formula –[P(Ph)(X)OR′O](x + 2)–[P(Ph)(X)OR′O](x + 3)– (X = S or Se) have been synthesized by the polycondensations of Et2N[P(Ph)(X)OR′O](x + 2)P(Ph)NEt2oligomers with HOR′O[P(Ph)(X)OR′O](x + 3)H oligomers followed by reaction with a chalcogen. The Et2N[P(Ph)(X)OR′O](x + 2)P(Ph)NEt2oligomers are prepared by the reaction of an excess of P(Ph)(NEt2)2with a diol while the HOR′O[P(Ph)(X)OR′O](x + 3)H oligomers are prepared by the reaction of P(Ph)(NEt2)2with an excess of the diol. In each case the excess, x is the same and determines the average block sizes. All of the polymers were characterized using1H,13C{1H}, and31P{1H} NMR spectroscopy, TGA, DSC, and SEC.31P{1H} NMR spectroscopy demonstrates that the random and block copolymers have the expected arrangements of monomers and, in the case of block copolymers, verifies the block sizes. All polymers are thermally stable up to ~300°C, and the arrangements of monomers in the copolymers (block vs. random) affect their degradation temperatures andTgprofiles. The polymers have weight average MWs of up to 3.8 × 104 Da.
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This content will become publicly available on March 26, 2026
The competitive strengths of hydrogen and halogen bonding to haloforms and their different spectroscopic markers
The ability of IR and NMR spectra to distinguish between hydrogen and halogen bonding of haloforms is assessed by quantum chemical calculations.
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- Award ID(s):
- 1954310
- PAR ID:
- 10624162
- Publisher / Repository:
- rsc
- Date Published:
- Journal Name:
- Physical Chemistry Chemical Physics
- Volume:
- 27
- Issue:
- 13
- ISSN:
- 1463-9076
- Page Range / eLocation ID:
- 6800 to 6809
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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