Olefin Metathesis Reaction Of Rubbers, Synthesis Of Functionalized Polyolefin And Property Investigation

Olefin metathesis was first discovered in1950's by Truett, since then many scientists began the research in this field, especially when the commercialization of well-defined Grubbs catalyst, it had entered into the rapid development period. Olefin metathesis mainly includes metathesis reaction and metathesis polymerization. The former contains olefins cross metathesis (CM), ring-opening metathesis (ROM), and alkene-alkyne metathesis. The latter includes ring-opening metathesis polymerization (ROMP) and acyclic diene metathesis (ADMET) polymerization. This thesis mainly involved CM and ROMP, the concrete content and the results were as follows:In the second chapter, the nature rubber (NR), gutta percha (TPI), polybutadiene rubber (BR), and styrene-butadiene rubber (SBR) which all have double bonds on polymer chains could carry out cross-metathesis reaction using Grubbs Ru-Ⅰ as catalyst. The product could be characterized by gel permeation chromatography (GPC) and differential scanning calorimetry (DSC). GPC results showed most products had unimodal and symmetrical traces indicating that the exchange of rubber segments went successfully and completely. While at the same time, most DSC detection showed a single Tg data belonging to the product further proved the success of CM.In the third chapter, a series of polymers containing random arrangement of electron rich (donor) and electron deficient (acceptor) aromatic units were synthesized by ROMP. The π-π and charge-transfer interactions were investigated by UV-vis spectroscopy and2D-NMR NOESY. UV-vis absorption spectra showed a new broad band in the long-wavelength region belonging to π-π and charge-transfer interactions, and it followed the expected Beer-Lambert behavior demonstrating the interactions occurred intramolecularly.2D-NMR NOESY contour clearly showed a correlation between aromatic protons further proved the existence of interactions. Such "donor-acceptor" type polymers may have potential applications in supramolecular chemistry, biochemistry and material chemistry.