Well-defined crosslinked materials via ring opening metathesis polymerisation

The work reported here is part of our ongoing programme of work directed. towards the synthesis and characterisation of polymeric materials via ROMP-RIM and ROMP-RTM. It describes the synthesis and characterisation of well-defined linear and crosslinked polymeric materials via ROMP-RTM. The process involves in-mould polymerisation of monofunctional imidonorbornene monomers, with different alkyl side chain lengths, to give a range of linear polymers. The process also involves in-mould copolymerisation of monofunctional imidonorbornene monomers, with different alkyl side chain lengths and difunctional monomers with different alkylene spacer lengths, to produce well-defined crosslinked polymers. The glass transition temperature (T_g) of the linear polymers was found to depend on the length of the alkyl side chain. For the crosslinked materials the results show that as the percentage of the difunctional, crosslinking unit, is increased (1, 5 and 10 molar percentage of the difunctional monomer) the glass transition shifts to a higher temperature, the height of the tanδ peak decreases and the plateau shear modulus above T_g increases. These results are as expected for an increase in the crosslink density of a polymer.