The effects of (a) varying C=C composition, (b) varying C=C : SH ratio, (c) varying DMPA photoinitiator, (d) varying post-cure time at 120°C at 1 torr, (e) varying wt % solvent present during UV curing, and (f) varying thiol crosslinker functionality on crosslink density of PU SMPs prepared from (x TMPAE: 1-x 3-MPD)-co-TMHDI thermoplasticpolyurethanes and polyfunctional thiol crosslinking agents.