Characterizing Mechanical and Gas Transport Properties of Nitrile Norbornene (NN) ROMP in Preparation for Analysis of OMe-NN-ROMP Block Copolymers

Abstract

This study characterized the mechanical and gas transport properties of nitrile norbornene ROMP. At a concentration of 0.15 M, the nitrile norbornene was able to successfully ROMP without becoming gel-like allowing for further characterization. The number average molecular weight was found to be 155 kDa with a polydispersity of 31.04. Thermal analysis of the nitrile norbornene ROMP indicated a T subscript g at 150 °C and a degradation temperature at 410 °C. The density nitrile norbornene ROMP was calculated to be 1.046 ± 0.0290 g/cm³. Using a simulation of the repeat unit the Van der Waals volume was found to be 73.4881 ± 0.1674 cm³ mol-1 and subsequently the fractional free volume was shown to be 0.1614 ± 0.028. The permeation of the 6 pure gases through the film were lower compared to OMe-ROMP with the highest permeating gases being He, H₂, and CO₂ . The selectivities for all the gases were higher than OMe-ROMP which is expected given the drop in permeation. The nitrile norbornene film did plasticize in intervals and the specific plasticization pressure is higher than 5 bar which is the CO₂-induced plasticization pressure point for the OMe-nitrile norbornene ROMP one-pot copolymers. Forming a block copolymer using nitrile norbornene ROMP with OMe-ROMP has potential for securing the mechanical stability from the nitrile norbornene ROMP while maintaining the high gas transport performance from the OMe-ROMP.