crta
Hrvatska znanstvena Sekcija img
bibliografija
3 gif
 Naslovna
 O projektu
 FAQ
 Kontakt
4 gif
Pregledavanje radova
Jednostavno pretraživanje
Napredno pretraživanje
Skupni podaci
Upis novih radova
Upute
Ispravci prijavljenih radova
Ostale bibliografije
Slični projekti
 Bibliografske baze podataka

Pregled bibliografske jedinice broj: 687176

Časopis

Autori: Mihelj, Tea; Popović, Jasminka; Skoko, Željko; Tomašić, Vlasta
Naslov: Thermotropic phase transitions of catanionic dodecylsulfates with multi-charged and multi-tailed quaternary ammonium centers
( Thermotropic phase transitions of catanionic dodecylsulfates with multi-charged and multi-tailed quaternary ammonium centers )
Izvornik: Thermochimica acta (0040-6031) 591 (2014); 119-129
Vrsta rada: članak
Ključne riječi: catanionic dodecylsulfates; thermotropism; basic lamellar thickness; tilt angle; multi-charged cationic surfactant; multi-tailed cationic surfactant
( catanionic dodecylsulfates; thermotropism; basic lamellar thickness; tilt angle; multi-charged cationic surfactant; multi-tailed cationic surfactant )
Sažetak:
Five novel anhydrous catanionic dodecylsulfates containing multi-charged and multi-tailed quaternary ammonium centers were synthesized and examined with light microscopy, differential scanning calorimetry and X-ray powder diffraction. This study is an attempt to explain the relationship between chemical structure, resulting molecular architecture, phase transition energetics, and intermolecular interactions of the individual amphiphiles that ultimately lead to mesomorphic product. All examined compounds are of typical layered structure at room temperature. The dimeric didodecylsulfate crystallizes in monoclinic, while trimeric tridodecylsulfate in triclinic crystal system, as obtained by X-ray powder diffraction. The long spacing, d/Å, decreases linearly with the increase of the ionic head number, and of n-dodecyl chain number. The thermal analysis of the samples indicates rich thermal behavior with thermotropic mesomorphism and polymorphism for all examined catanionics, as well as isotropisation accompanied by decomposition for three-headed and three-tailed dodecylsulfates. Their thermal behavior is greatly promoted by the quaternary ammonium centers. Examined catanionics show thermotropic phases over a broader temperature range due to the ability to accommodate chain disorder and strong ionic interactions. Maltese crosses, oily streaks textures, stepped drops and fan-shaped textures affirmed the existence of various smectic mesophases.
Projekt / tema: 098-0982915-2949, 119-0982886-1009
Izvorni jezik: eng
Rad je indeksiran u
bazama podataka:
Current Contents Connect (CCC)
Scopus
SCI-EXP, SSCI i/ili A&HCI
Science Citation Index Expanded (SCI-EXP) (sastavni dio Web of Science Core Collectiona)
Kategorija: Znanstveni
Znanstvena područja:
Kemija
URL Internet adrese: http://www.journals.elsevier.com/thermochimica-acta
Broj citata:
Altmetric:
DOI: 10.1016/j.tca.2014.07.024
URL cjelovitog teksta:
Google Scholar: Thermotropic phase transitions of catanionic dodecylsulfates with multi-charged and multi-tailed quaternary ammonium centers
Upisao u CROSBI: Tea Mihelj (Tea.Mihelj@irb.hr), 6. Vel. 2014. u 14:08 sati



  Verzija za printanje   za tiskati


upomoc
foot_4