title: [The interaction between La and polyurethane system].
abstract: A series of polyether polyurethane (PU)-LaCl3 composites with different lanthanum contents were prepared. DSC results indicate that LaCl3 promotes phase transition behavior of the LaCl3/PU composites, which causes the endothermic peak at 11.58 degrees C to disappear. FTIR spectroscopy demonstrates that significant variation can be observed. The peak at 1633 cm(-1) attributed to carbonyl vibration and the peak at 3311 cm(-1) attributed to N-H stretching band moves to 1647 cm(-1) and 3355 cm(-1), respectively, when LaCl3 is introduced into the PU system. A new band (-200 cm(-1)) assigned to the La-O band was observed, and the far IR result provided a direct evidence of the coordination between La3+ ion and C=O group of PU system.
authors.affiliation: The State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Liu
authors.forename: Xin-hai
authors.initials: XH
authors.lastname: Liu
authors.forename: Chi-cheng
authors.initials: CC
authors.lastname: Cao
authors.forename: Xian-yu
authors.initials: XY
authors.lastname: Sun
authors.forename: Shi-fu
authors.initials: SF
authors.lastname: Weng
authors.forename: Duan-fu
authors.initials: DF
authors.lastname: Xu
authors.forename: Jin-guang
authors.initials: JG
authors.lastname: Wu