Equation 2 was solved for a hollow cylinder of initial length 𝑙 0 and initial thickness ℎ 0 and modified by a constant 𝛽 to account for "instantaneous" mass loss due to leachable plasticizer or other initial jumps in mass loss between the initial mass and the first time point to yield Equation 3. Accordingly, the trivial initial data point of zero mass loss at time zero was not included in any model fitting.