Matches in SemOpenAlex for { <https://semopenalex.org/work/W3000887310> ?p ?o ?g. }
Showing items 1 to 89 of
89
with 100 items per page.
- W3000887310 endingPage "101650" @default.
- W3000887310 startingPage "101650" @default.
- W3000887310 abstract "The molecular structure of a crosslinked nitrogen-rich resin made from melamine, urea, and aldehydes, and of microcapsules made from the reactive resin with multiple polymeric components in aqueous dispersion, has been analyzed by 13C, 13C{1H}, 1H–13C, 1H, 13C{14N}, and 15N solid-state NMR without isotopic enrichment. Quantitative 13C NMR spectra of the microcapsules and three precursor materials enable determination of the fractions of different components. Spectral editing of non-protonated carbons by recoupled dipolar dephasing, of CH by dipolar DEPT, and of C–N by 13C{14N} SPIDER resolves peak overlap and helps with peak assignment. It reveals that the N- and O-rich resin “imitates” the spectrum of polysaccharides such as chitin, cellulose, or Ambergum to an astonishing degree. 15N NMR can distinguish melamine from urea and guanazole, NC=O from COO, and primary from secondary amines. Such a comprehensive and quantitative analysis enables prediction of the elemental composition of the resin, to be compared with combustion analysis for validation. It also provides a reliable reference for iterative simulations of 13C NMR spectra from structural models. The conversion from quantitative NMR peak areas of structural components to the weight fractions of interest in industrial practice is derived and demonstrated. Upon microcapsule formation, 15N and 13C NMR consistently show loss of urea and aldehyde and an increase in primary amines while melamine is retained. NMR also made unexpected findings, such as imbedded crystallites in one of the resins, as well as persistent radicals in the microcapsules. The crystallites produce distinct sharp lines and are distinguished from liquid-like components by their strong dipolar couplings, resulting in fast dipolar dephasing. Fast 1H spin–lattice relaxation on the 35-ms time scale and characteristically non-exponential 13C spin–lattice relaxation indicate persistent radicals, confirmed by EPR. Through 1H spin diffusion, the mixing of components on the 5-nm scale was documented." @default.
- W3000887310 created "2020-01-30" @default.
- W3000887310 creator A5004494409 @default.
- W3000887310 creator A5028333635 @default.
- W3000887310 creator A5056514225 @default.
- W3000887310 creator A5057292950 @default.
- W3000887310 creator A5065870564 @default.
- W3000887310 creator A5073977617 @default.
- W3000887310 creator A5080244245 @default.
- W3000887310 date "2020-04-01" @default.
- W3000887310 modified "2023-09-29" @default.
- W3000887310 title "Multinuclear solid-state NMR of complex nitrogen-rich polymeric microcapsules: Weight fractions, spectral editing, component mixing, and persistent radicals" @default.
- W3000887310 cites W1966910457 @default.
- W3000887310 cites W1970567067 @default.
- W3000887310 cites W1974292200 @default.
- W3000887310 cites W2022590144 @default.
- W3000887310 cites W2022790651 @default.
- W3000887310 cites W2055516309 @default.
- W3000887310 cites W2064104914 @default.
- W3000887310 cites W2065526959 @default.
- W3000887310 cites W2084333313 @default.
- W3000887310 cites W2090647948 @default.
- W3000887310 cites W2115682140 @default.
- W3000887310 cites W2120901082 @default.
- W3000887310 cites W2209065720 @default.
- W3000887310 cites W2571110907 @default.
- W3000887310 cites W2602833127 @default.
- W3000887310 cites W2606268857 @default.
- W3000887310 cites W2807791345 @default.
- W3000887310 cites W2947410894 @default.
- W3000887310 cites W4254297188 @default.
- W3000887310 doi "https://doi.org/10.1016/j.ssnmr.2020.101650" @default.
- W3000887310 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/32044558" @default.
- W3000887310 hasPublicationYear "2020" @default.
- W3000887310 type Work @default.
- W3000887310 sameAs 3000887310 @default.
- W3000887310 citedByCount "3" @default.
- W3000887310 countsByYear W30008873102022 @default.
- W3000887310 countsByYear W30008873102023 @default.
- W3000887310 crossrefType "journal-article" @default.
- W3000887310 hasAuthorship W3000887310A5004494409 @default.
- W3000887310 hasAuthorship W3000887310A5028333635 @default.
- W3000887310 hasAuthorship W3000887310A5056514225 @default.
- W3000887310 hasAuthorship W3000887310A5057292950 @default.
- W3000887310 hasAuthorship W3000887310A5065870564 @default.
- W3000887310 hasAuthorship W3000887310A5073977617 @default.
- W3000887310 hasAuthorship W3000887310A5080244245 @default.
- W3000887310 hasBestOaLocation W30008873101 @default.
- W3000887310 hasConcept C103319777 @default.
- W3000887310 hasConcept C113196181 @default.
- W3000887310 hasConcept C121332964 @default.
- W3000887310 hasConcept C153202636 @default.
- W3000887310 hasConcept C163111631 @default.
- W3000887310 hasConcept C178790620 @default.
- W3000887310 hasConcept C185592680 @default.
- W3000887310 hasConcept C2775979504 @default.
- W3000887310 hasConcept C2779251873 @default.
- W3000887310 hasConcept C46141821 @default.
- W3000887310 hasConceptScore W3000887310C103319777 @default.
- W3000887310 hasConceptScore W3000887310C113196181 @default.
- W3000887310 hasConceptScore W3000887310C121332964 @default.
- W3000887310 hasConceptScore W3000887310C153202636 @default.
- W3000887310 hasConceptScore W3000887310C163111631 @default.
- W3000887310 hasConceptScore W3000887310C178790620 @default.
- W3000887310 hasConceptScore W3000887310C185592680 @default.
- W3000887310 hasConceptScore W3000887310C2775979504 @default.
- W3000887310 hasConceptScore W3000887310C2779251873 @default.
- W3000887310 hasConceptScore W3000887310C46141821 @default.
- W3000887310 hasFunder F4320333199 @default.
- W3000887310 hasLocation W30008873101 @default.
- W3000887310 hasOpenAccess W3000887310 @default.
- W3000887310 hasPrimaryLocation W30008873101 @default.
- W3000887310 hasRelatedWork W1967421497 @default.
- W3000887310 hasRelatedWork W1968763660 @default.
- W3000887310 hasRelatedWork W1986734711 @default.
- W3000887310 hasRelatedWork W2012708703 @default.
- W3000887310 hasRelatedWork W2080972505 @default.
- W3000887310 hasRelatedWork W2091573303 @default.
- W3000887310 hasRelatedWork W2093881621 @default.
- W3000887310 hasRelatedWork W2389198072 @default.
- W3000887310 hasRelatedWork W2414274587 @default.
- W3000887310 hasRelatedWork W2482061561 @default.
- W3000887310 hasVolume "106" @default.
- W3000887310 isParatext "false" @default.
- W3000887310 isRetracted "false" @default.
- W3000887310 magId "3000887310" @default.
- W3000887310 workType "article" @default.