Although both polymers showed swelling upon infiltration of TMA, they show different behavior. Swelling in PLA followed a generally linear trend starting from 1 TMA, with an average swelling of 8.6 % per TMA and reaching a maximum swelling of 136 % at saturation. For PMMA the swelling for the initial two TMA infiltration was much higher, on average 16.8 %. Upon addition of more TMA the swelling was lower, leading to an average swelling of 7.