Various synthetic factors that affect the molecular weight, yield, and composition of maleic anhydride (MAH), norbornene (Nb), and tert-butyl 5-norbornene-2-carboxylate (Nb-TBE) terpolymers were investigated. Real-time monitoring via in-situ FTIR spectroscopy of co- and terpolymerizations of MAH with Nb and Nb-TBE was utilized to evaluate the observed rates of varying Nb/Nb-TBE monomer feed ratios. Pseudo-first-order kinetic analysis indicated that the observed rate of reaction (kobs) was a strong function of the Nb/Nb-TBE ratio with a maximum of 6.68 × 10-5 s-1 for a 50/0/50 Nb/Nb-TBE/MAH monomer ratio and a minimum of 1.13 × 10-5 s-1 for a 0/50/50 Nb/Nb-TBE/MAH ratio. In addition, polymer yields were also observed to be a function of the Nb/Nb-TBE ratio and also decreased with increasing Nb-TBE. Sampling of an Nb/Nb-TBE/MAH (25/25/50 mole ratio) terpolymerization and subsequent analysis using 1H NMR indicated that the relative rate of Nb incorporation is approximately 1.7 times faster than Nb-TBE incorp...