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Updated: May 23, 2026

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Multivariate statistical analysis of mid-infrared spectra for a G1 allyl-terminated carbosilane dendrimer
Maria-Cristina Popescu1, Bogdan C Simionescu
1Petru Poni Institute of Macromolecular Chemistry of Romanian Academy, Iasi, Romania. cpopescu@icmpp.ro
Abstract:
The FTIR spectra were measured for G1 allyl terminated carbosilane dendrimer over a temperature range of 25-200°C to explore the temperature-dependent changes. The dendrimer spectra exhibited complicated patterns and thus were analyzed by both the exploratory principal component analysis (PCA) and two-dimensional (2D) correlation spectroscopy. Boltzmann fitting and score plots of PCA evidenced the phase transition temperature to be about 172°C. Frequency variables, which strongly contributed to each principal component highlighted in their loadings plot, were linked to the frequencies assigned to vibrations of the CH(2) and CH(3) groups, as well as to vibrations of the SiCH groups. 2D correlation spectroscopy discerned all the sequences of group motion of dendrimer, indicating that during the heating process a reorganization of core structure takes place, followed by a conformational rearrangement of the terminal units.
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