title: The use of N,N'-diallylaldardiamides as cross-linkers in xylan derivatives-based hydrogels.
abstract: N,N'-Diallylaldardiamides (DA) were synthesized from galactaric, xylaric, and arabinaric acids, and used as cross-linkers together with xylan (X) derivatives to create new bio-based hydrogels. Birch pulp extracted xylan was derivatized to different degrees of substitution of 1-allyloxy-2-hydroxy-propyl (A) groups combined with 1-butyloxy-2-hydroxy-propyl (B) and/or hydroxypropyl (HP) groups. The hydrogels were prepared in water solution by UV induced free-radical cross-linking polymerization of derivatized xylan polymers without DA cross-linker (xylan derivative hydrogel) or in the presence of 1 or 5 wt% of DA cross-linker (DA hydrogel). Commercially available cross-linker (+)-N,N'-diallyltartardiamide (DAT) was also used. The degree of substitution (DS) of A, B, and HP groups in xylan derivatives was analyzed according to (1)H NMR spectra. The DS values for the cross-linkable A groups of the derivatized xylans were 0.4 (HPX-A), 0.2 (HPX-BA), and 0.4 (X-BA). The hydrogels were examined with FT-IR and elemental analysis which proved the cross-linking successful. Water absorption of the hydrogels was examined in deionized water. Swelling degrees up to 350% were observed. The swollen morphology of the hydrogels was assessed by scanning electron microscopy (SEM). The presence of cross-linkers in DA hydrogels had only a small impact on the water absorbency when compared to xylan derivative hydrogels but a more uniform pore structure was achieved.
authors: Technical Research Centre of Finland (VTT), Biologinkuja 7, FI-02044 Espoo, Finland.
authors: Helinä
authors: H
authors: Pohjanlehto
authors: Harri
authors: H
authors: Setälä
authors: Kari
authors: K
authors: Kammiovirta
authors: Ali
authors: A
authors: Harlin
mesh_terms: D000498:Allyl Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D003432:Cross-Linking Reagents / Q000138:chemical synthesis* / Q000737:chemistry; D020100:Hydrogels / Q000138:chemical synthesis* / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D009682:Magnetic Resonance Spectroscopy; D008855:Microscopy, Electron, Scanning; D015394:Molecular Structure; D017550:Spectroscopy, Fourier Transform Infrared; D013400:Sugar Acids / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D000498:Allyl Compounds; D003432:Cross-Linking Reagents; D020100:Hydrogels; C570778:N,N'-diallylarabinardiamide; C570779:N,N'-diallylgalactardiamide; C570777:N,N'-diallylxylardiamide; D013400:Sugar Acids