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1.
Macromol Rapid Commun ; 33(23): 2029-34, 2012 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-22972750

RESUMEN

Poly(furfuryl isocyanate) (PFIC), which includes the reactive furan group, was synthesized by anionic polymerization using a sodium benzhydroxide (Na-BH), self-assembly initiator. We determined the optimum polymerization conditions by varying both the reaction time and the molar ratio of the monomer to the initiator. Block copolymer, poly(furfuryl isocyanate)-b-poly(n-hexyl isocyanate), was synthesized under optimized polymerization conditions. The PFIC was modified by Diels-Alder reactions with C60 for functionalization. Transmission electron microscopy (TEM) was used to study the self-assembly of block copolymers and modified block copolymer with C60. C60 formed highly ordered aggregates on the PFIC domains via self-assembly of the block copolymer.


Asunto(s)
Fulerenos/química , Poliuretanos/química , Microscopía Electrónica de Transmisión , Polimerizacion , Poliuretanos/síntesis química
2.
J Chromatogr A ; 1376: 98-104, 2015 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-25533396

RESUMEN

The chemical homogeneity of telechelic polyisobutylene diol (PIB-diol), prepared by hydroboration-oxidation of allyl telechelic PIB obtained by reacting living PIB with allyltrimethylsilane, was investigated by liquid chromatography at critical conditions (LCCC) and HPLC coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). A normal phase gradient HPLC method was developed that was able to separate the as-synthesized PIB-diol into three components; PIB-diol, PIB-monool and PIB without any OH functionality. These were analyzed by MALDI-TOF MS, which suggested that the reaction of living PIB with allyltrimethylsilane was incomplete. LCCC using refractive index (RI) detector as a concentration detector allowed separation and quantification of PIB species according to their chemical heterogeneity (PIB-diol=95.3%, PIB-monool=3.3%, non-functional PIB=1.4%). The calculated number average functionality (Fn) of PIB-diol=1.94 suggests high quality of PIB-diol suitable for high molecular weight polyurethane synthesis.


Asunto(s)
Polímeros/química , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
3.
Chem Commun (Camb) ; 48(6): 826-8, 2012 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-22016883

RESUMEN

Poly(n-hexyl isocyanate) (PHIC) with varying molecular weights were synthesized using a chiral initiator and chiral terminator by living anionic polymerization. In such PHICs, chirality of the initiator plays a decisive role in determining the helical sense of the entire polymeric chain, whereas chirality of the terminator plays a supportive role.


Asunto(s)
Nitrilos/síntesis química , Dicroismo Circular , Conformación Molecular , Peso Molecular , Nitrilos/química , Estereoisomerismo
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