Browsing by Autor "E. Laredo"

Filter results by typing the first few letters
Now showing 1 - 3 of 3
  • Thumbnail Image
    Item type: Item ,
    Comblike Complexes of Poly(itaconic acid) and Poly(mono methyl itaconate) and Alkyltrimethylamonium Cationic Surfactants
    (Springer Science+Business Media, 2006) María E. Báez; Eucarys Jiménez; E. Laredo; Montserrat García‐Alvarez; Antxon Martı́nez de Ilarduya; Francisco López‐Carrasquero
  • Thumbnail Image
    Item type: Item ,
    Molecular dynamics in nanophase-separated comb-like poly( $ \upalpha$ - n-alkyl $ \upbeta$ -L-aspartate)s
    (Springer Science+Business Media, 2004) M. Grimau; E. Laredo; Francisco Sánchez; Francisco López‐Carrasquero; María E. Báez; A. Bello
  • Thumbnail Image
    Item type: Item ,
    Ring-opening copolymerization of (R,S)-β-butyrolactone and ε-caprolactone using sodium hydride as initiator
    (Budapest University of Technology and Economics, 2010) Meribary Monsalve; Jesús Contreras; E. Laredo; Francisco López‐Carrasquero
    Copolymers of racemic -butyrolactone ((R,S)-BL) and -caprolactone (CL), were synthesized by ring-opening polymerization initiated by sodium hydride (NaH). The initiator exhibited a satisfactory catalytic activity, producing copolymers whose yields are greatly influenced by the feed monomer ratio, CL/BL. All polymers obtained were characterized by nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and wide angle X-rays scattering, WAXS. The molar composition of copolyesters determined by 1 H-NMR spectra, showed that the incorporation of CL is favoured over the incorporation of (R,S)-BL. Gel permeation chromatography and 13 C-NMR spectra indicated that CL/BL copolymers had block sequence distribution. The TGA analysis of copolymers showed that these copolymers are stable up to temperatures near 200C, followed by a decomposition process in two steps; the first one is attributed to the (R,S)-BL block degradation and the second to the remaining PCL block. The crystallization process of these copolymers was studied by DSC and WAXS showing that the amorphous (R,S)-BL segments chains did not affect the crystallinity of the PCL blocks.