Degradation Kinetics and Time–Temperature Superposition for Lifespan Assessment of Traditional Chinese Handmade Papers: A Critical Review and Methodological Evaluation

Traditional Chinese handmade papers are important carriers of cultural heritage, but their long-term durability is difficult to evaluate directly because natural ageing occurs over very long timescales. This critical review synthesises cellulose degradation kinetics and evaluates the applicability of time–temperature superposition (TTSP) to lifespan prediction of traditional Chinese handmade papers. A PRISMA-informed evidence selection workflow was combined with a descriptive comparison of reported activation energies and a worked TTSP re-expression using published multi-temperature kinetic parameters. Reported apparent activation energies varied markedly among paper systems, treatments, ageing configurations, measured endpoints, and kinetic models. Because several entries were not statistically independent and were not derived from a common experimental design, they were not averaged into a universal kinetic parameter. Among the available studies, bark paper provided the most complete traditional Chinese handmade paper multi-temperature dataset. Re-expression of its published rate constants in TTSP coordinates produced the expected curve superposition; however, this follows algebraically from the fitted Ekenstam rate constants and therefore illustrates the calculation rather than providing independent empirical validation. For Xuan, bamboo, and other traditional papers, independently measured multi-temperature degradation trajectories suitable for direct TTSP testing remain limited. Future studies should derive paper-specific kinetic parameters from controlled multi-temperature experiments, propagate kinetic and endpoint uncertainty during lifespan extrapolation, and combine molecular, mechanical, and appearance-related indicators.