Short crosslink structure and amorphous nature are the major reasons for the poor performance of cured epoxidized soybean oil (ESO) thermosets. Herein, a biobased crystalline oligomeric poly(butylene succinate) (OPBS) with dicarboxyl terminal groups was used as a long-chained and crystalline curing agent to increase the segment length within crosslinking points and make the cured thermoset to crystallize. The molecular weight of OPBS affected the curing process significantly. The curing rate decreased with increase in the molecular weight of OPBS. Addition of 4-N, N-dimethylaminopyridine as a catalyst accelerated the curing rate efficiently. The crosslink density decreased gradually with increase in the molecular weight of OPBS. The segment length of OPBS had a strong influence on the physical properties of the cured thermoset. The crystallization enhanced gradually with increasing segment length of OPBS, which then resulted in considerable improvement in melting temperature, mechanical strength and heat resistance of the thermoset. With improved mechanical properties and heat resistance, the fully biobased ESO thermosets could find more applications.

短的交联结构和无定形性质是固化的环氧化大豆油（ESO）热固性塑料性能差的主要原因。在此，使用具有二羧基末端基团的生物基结晶低聚聚丁二酸丁二酯（OPBS）作为长链结晶固化剂，以增加交联点内的链段长度并使固化的热固性材料结晶。OPBS的分子量显着影响固化过程。固化速率随OPBS分子量的增加而降低。加入4-N，N-二甲基氨基吡啶作为催化剂有效地提高了固化速率。随着OPBS分子量的增加，交联密度逐渐降低。OPBS的链段长度对固化的热固性塑料的物理性能有很大的影响。随着OPBS链段长度的增加，结晶逐渐增强，这导致热固性材料的熔融温度，机械强度和耐热性得到显着改善。凭借改善的机械性能和耐热性，完全基于生物的ESO热固性材料可以找到更多的应用。