Copolymerization of Propylene with Higher α-Olefins by a Pyridylamidohafnium Catalyst: An Effective Approach to Polypropylene-Based Elastomer

In this contribution, we explored the copolymerization of propylene with higher α-olefins, including 1-octene (C8) 1-dodecene (C12), 1-hexadecene (C16) and 1-eicosene (C20), by using a dimethyl pyridylamidohafnium catalyst. A series of copolymers with varied comonomer incorporation, high molecular weight and narrow molecular weight distribution were obtained at mild conditions. The effects of the insertion of the comonomers on the microstructure, thermal and final mechanical properties were systemically studied by 13C NMR, wide-angle X-ray scattering, DSC and tensile test. Excellent mechanical performances were achieved by tuning the incorporation and chain length of the higher α-olefins. When the comonomer content reached above 12 mol.%, polypropylene-based elastomers were obtained with high ductility. A combination of excellent elastic recovery and flexibility was achieved for the P/C16 copolymers with about 20 mol.% monomer incorporation. The monomer incorporation and side chain length played a crucial role in determining the mechanical property of the outstanding polypropylene-based elastomers.

The Effects of Enhancing the Crosslinking Degree in High Internal Phase Emulsion Templated Poly(dicyclopentadiene) Cured by Ring-Opening Metathesis Polymerization by a Crosslinking Comonomer

The effect of enhancing the crosslinking degree in polyHIPEs made from dicyclopentadiene by additionally using a crosslinking comonomer is described. Foams of 80% porosity with 10-40 w% comonomer content in the continous phase are prepared and show similar porosities and morphological characteristics as foams prepared with dicyclopentadiene alone. Assessing the mechanical properties reveals that the ductility is decreasing while the stiffness of the samples is increasing with increasing comonomer content. The foams containing the crosslinking comonomer take up at least five fold mass of toluene therby swelling to at least 30 v%. Upon drying of the swollen specimens, their initial shap and porosity are recovered. This feature distinguishes them from polyHIPEs made from dicyclopentadiene only.<br>

The Effects of Enhancing the Crosslinking Degree in High Internal Phase Emulsion Templated Poly(dicyclopentadiene) Cured by Ring-Opening Metathesis Polymerization by a Crosslinking Comonomer

The effect of enhancing the crosslinking degree in polyHIPEs made from dicyclopentadiene by additionally using a crosslinking comonomer is described. Foams of 80% porosity with 10-40 w% comonomer content in the continous phase are prepared and show similar porosities and morphological characteristics as foams prepared with dicyclopentadiene alone. Assessing the mechanical properties reveals that the ductility is decreasing while the stiffness of the samples is increasing with increasing comonomer content. The foams containing the crosslinking comonomer take up at least five fold mass of toluene therby swelling to at least 30 v%. Upon drying of the swollen specimens, their initial shap and porosity are recovered. This feature distinguishes them from polyHIPEs made from dicyclopentadiene only.<br>

Dual catalysis for the copolymerisation of epoxides and lactones

Using a dual catalysis approach, epoxide/lactone copolymers were synthesized with control over tacticity, molecular weight, crystallinity, and comonomer content.