Study on the intercrystalline of Eucommia Ulmoides (EU) gum by WAXD/SAXS

Eucommia Ulmoides ( EU ) gum, an intermediate material between plastics and rubber, was studied for its three-phase crystalline structure: crystalline, intercrystalline, and amorphous phases. Using WAXD and SAXS, the melting and stretching behavior of EU gum was investigated. SAXS peaks appeared at 30°C and 40°C but disappeared at 50°C, with intercrystalline thickness measured at 1.25–1.28 nm. As temperature increased, intercrystallinity rose while crystallinity decreased. Stretching led to weakened crystallization peaks and molecular chain orientation. Correlation functions showed a reduction in both intercrystallinity (10.42% to 6.42%) and crystallinity (23.23% to 17.39%), highlighting structural disruption due to chain realignment. These findings provide new insights into the phase transitions and crystallization mechanisms of intermediate polymers. • In-situ SAXS/WAXD reveals a three-phase structure in Eucommia Ulmoides gum. • The transition layer content increases with temperature while crystallinity decreases. • Stretching induces crystal destruction instead of strain-induced crystallization. • Porod analysis quantifies interfacial changes during deformation. • This study establishes a new paradigm for crystalline rubber characterization and modulation.