Poly(l-lactic acid) (PLLA) modified by a new organic nucleating agent, N,N′-dodecanedioic bis(piperonylic acid) dihydrazide (BPADD), was fabricated, and its crystallization, melting behavior, thermal stability, fluidity and mechanical properties were investigated. The melt-crystallization behavior proved that BPADD could bring about a fast nucleation rate to promote the crystallization of PLLA; 2 wt% BPADD exhibited the best crystallization accelerating effect due to having the highest crystallization onset temperature and the highest melt-crystallization temperature. However, PLLA/3% BPADD had the largest melt-crystallization enthalpy. In addition, the frontier orbital energy indicated that the nucleation effect of BPADD on PLLA might be attributed to intermolecular interaction. The melt crystallization also depended on two critical factors, the cooling rate and final melting temperature. An increase in BPADD content led to greater inhibition of crystal growth during cold crystallization. The differences in the melting behavior of PLLA/BPADD samples reflected the previous crystallization process, the heating rate and BPADD content. BPADD was harmful to maintaining the thermal stability of PLLA; however, the intermolecular interaction could prevent the decomposition onset temperature from continuously decreasing. The usage of BPADD resulted in better fluidity and higher tensile strength; the tensile modulus and elongation at break were associated with BPADD content.

中文翻译：

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修改后的 PLLA：BPADD 对属性的影响

制备了新型有机成核剂N,N'-十二烷二酸双(胡椒酸)二酰肼(BPADD)改性的聚(L-乳酸)(PLLA)，并对其结晶、熔融行为、热稳定性、流动性和力学性能进行了研究。属性进行了调查。熔融结晶行为证明，BPADD可以带来较快的成核速率，促进PLLA的结晶；2 wt% BPADD由于具有最高的结晶起始温度和最高的熔融结晶温度而表现出最好的结晶加速效果。然而，PLLA/3% BPADD 具有最大的熔融结晶焓。此外，前沿轨道能量表明，BPADD对PLLA的成核作用可能归因于分子间相互作用。熔体结晶还取决于两个关键因素，冷却速度和最终熔化温度。BPADD 含量的增加导致在冷结晶过程中对晶体生长的抑制作用更大。PLLA/BPADD 样品熔融行为的差异反映了先前的结晶过程、加热速率和 BPADD 含量。BPADD不利于维持PLLA的热稳定性；然而，分子间相互作用可以防止分解起始温度持续降低。BPADD的使用导致更好的流动性和更高的抗拉强度；拉伸模量和断裂伸长率与 BPADD 含量有关。PLLA/BPADD 样品熔融行为的差异反映了先前的结晶过程、加热速率和 BPADD 含量。BPADD不利于维持PLLA的热稳定性；然而，分子间相互作用可以防止分解起始温度持续降低。BPADD的使用导致更好的流动性和更高的抗拉强度；拉伸模量和断裂伸长率与 BPADD 含量有关。PLLA/BPADD 样品熔融行为的差异反映了先前的结晶过程、加热速率和 BPADD 含量。BPADD不利于维持PLLA的热稳定性；然而，分子间相互作用可以防止分解起始温度持续降低。BPADD的使用导致更好的流动性和更高的抗拉强度；拉伸模量和断裂伸长率与 BPADD 含量有关。