بررسی رابطه غیرخطی انعطاف پذیری مالی و پایداری شرکت با توجه به نقش تعدیلگر کارایی سرمایه گذاری

While corporate sustainability has become a key management priority, the impact of resource management and financial flexibility on sustainable performance is non-linear and moderated by investment efficiency. Accordingly, this study aims to examine the non-linear relationship between financial flexibility and firm sustainability, considering the moderating role of investment efficiency. This applied, descriptive-correlational study examines a sample of 141 companies listed on the Tehran Stock Exchange from 2015 to 2024. Data gathered via archival and field methods were analyzed using multiple regression in EViews. The results reveal an inverted U-shaped relationship between financial flexibility and firm sustainability performance (coefficient = 0.02, significant at the 95% level), as well as between financial flexibility and sustainable financial performance (coefficient = 0.145, significant at the 95% level). Furthermore, the interaction term between financial flexibility and investment efficiency (coefficient = 0.443) is significant at the 90% level, confirming its moderating role in the relationship between financial flexibility and sustainability performance. Finally, the interaction term between investment efficiency and the squared term of financial flexibility (coefficient = 3.651) is significant at the 95% level, indicating that investment efficiency moderates the relationship between financial flexibility and sustainable financial performance.