MALDI-TOF is routinely used to charecterize polymers, oligomers, polymerization mechanisms etc. MS coupled with pyrolysis GC can be used for characterizing polymer structure (e.g. copolymers). Headspace GC analysis coupled with MS can be used to characterize volatile additives in polymers. Using liquid or supercritical extraction coupled with GC-MS can also be used for higher molecular additives. SIMS can be used for the characterization of polymer surfaces (combined with ion bombardment it can bes used to charactrize the top few layers - e.g. degradation). What is your problem to be solved by MS? It is possible that there are alternative methods - MS is not typically a polymer research tool (with the exception of MALDI-TOF).

Mass spectroscopy is not the solution for protein analysis rather protein crystallography is the the best choice.