**4. Conclusions**

Storage time can significantly modify the physicochemical, morphological, and structural properties of biodegradable films comprising starch, chitosan, and poloxamer. This information is important to ascertain the state of packaging materials of biodegradable origin when stored at room temperature. Based on physicochemical characterization, there is evidence suggesting that poloxamer avoids the retrogradation of cornstarch. The biodegradable films showed a slight modification in their surface morphology after 16 months, similar to erosion, and this phenomenon can modify the color, WS, mechanical behavior, and wettability of films. Lower melting temperatures and enthalpies in the poloxamer films, as well as storage for 16 months, indicate that the retrogradation of amylopectin only partially recovers the crystalline structure of the native starch. The use in the pharmaceutical, medical, and packaging industry of a biodegradable material such as the one developed in this study may be possible, owing to the favorable properties observed in its mechanical performance and acceptable solubility in liquid water, which can be sufficiently solubilized in a short period of time with the presence of the poloxamer.

**Supplementary Materials:** The following are available online at https://www.mdpi.com/article/ 10.3390/polym13142341/s1, Figure S1: DSC thermograms of biodegradable films of corn starchchitosan with pluronic F127 at ratios of 0%, 1%, 3%, and 5% and stored for 0 and 16 months.

**Author Contributions:** Conceptualization, A.F.-G., E.J.J.-R. and R.Y.A.-L.; methodology, A.F.-G. and R.Y.A.-L.; formal analysis, A.F.-G., C.C. and R.Y.A.-L.; investigation, A.F.-G., E.J.J.-R. and R.Y.A.-L.; visualization, A.F.-G., E.J.J.-R. and R.Y.A.-L.; supervision, E.J.J.-R. and R.Y.A.-L.; project administration, E.J.J.-R. and R.Y.A.-L.; writing—original draft preparation, A.F.-G., C.C., E.J.J.-R., G.M. and R.Y.A.-L.; writing—review and editing, A.F.-G., C.C., E.J.J.-R., G.M. and R.Y.A.-L. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by Centro de Investigación en Química Aplicada (CIQA) under internal projects 6521 and 6610, and by Dirección General de Investigaciones (DGI) of Universidad Santiago de Cali under call no. 01-2021.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** The data presented in this study are available on request from the corresponding author.

**Acknowledgments:** Thank you to M.C. Maria Guadalupe Mendez-Padilla and M.C. Myrna Salinas Hernández, M.C. Blanca Huerta Martinez, and LNMG-CIQA for DSC, DRX, and SEM characterizations, respectively. Fonseca-García and Aguirre-Loredo thank CONACYT for their nominations as a researchers assigned to CIQA.

**Conflicts of Interest:** The authors declare no conflict of interest.
