**4. Conclusions**

The hydrophobic UV absorption nanofiller was prepared by SA-modified Zn-Ti LDH. The dispersed m-LDH in PBSA matrix shows its stacking structure via WAXD analysis. While not affecting the crystal structure of PBSA, both the crystallization temperature and crystallinity of PBSA/m-LDH composites were increased due to the addition of m-LDH with heterogeneous nucleation. The composite with 1 wt% m-LDH content had the highest T<sup>c</sup> and crystallinity, which are 52.9 ◦C and 31.0%, respectively. In addition, the mechanical properties of the composite were enhanced with increasing m-LDH content. By adding 5 wt% m-LDH into PBSA, the storage modulus at −80 ◦C increased from 4.04 GPa of neat PBSA matrix to 6.16 GPa of composites. The m-LDH decreased the photodegradation behavior of PBSA, which was confirmed by GPC, FTIR, and SEM analysis. This may attribute to m-LDH absorbs the partial incident light entering the composite and reduces the effect of UV radiation. Based on the fact that both Zn-Ti LDH, SA, and PBSA are biocompatible and have low toxicity, the biofriendly composites with photodegradationresistant properties could be deployed for suitable applications, such as biodegradable mulching films.

**Author Contributions:** Conceptualization, J.-M.W. and T.-M.W.; methodology, T.-M.W.; software, E.-C.C. and J.-M.W.; validation, H.W. and J.-M.W.; formal analysis, J.-M.W. and H.W.; investigation, Y.-J.C. and E.-C.C.; resources, E.-C.C.; data curation, Y.-J.C. and J.-M.W.; writing—original draft preparation, Y.-J.C. and J.-M.W.; writing—review and editing, T.-M.W.; visualization, T.-M.W.; supervision, T.-M.W.; project administration, T.-M.W.; funding acquisition, T.-M.W. All authors have read and agreed to the published version of the manuscript.

**Funding:** Not applicable.

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

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Acknowledgments:** The financial support of this work is provided by the Ministry of Science and Technology (MOST) under Grand MOST 109-2221-E-005-069-NY3 and the Ministry of Education under the project of Innovation and Development Center of Sustainable Agriculture (IDCSA). The authors would like to thank the Instrument Center of National Chung Hsing University for help with measurements of Transmission electron microscopy.

**Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.
