Title: Influence of Organic Nucleating Agents on the Crystallization Behavior of Polylactic Acid

Authors: Peng Gao, Saeed Alanazi, Davide Masato

DOI: 10.33599/nasampe/s.24.0030

Abstract: This paper investigates the use of Orotic Acid (OA) and Ethylene Bis-Stearamide (EBS) as nucleating agents to augment the quiescent crystallization of Polylactic Acid (PLA) within the temperature range of 80 °C to 140 °C. Through melt processing, various blends were synthesized and subsequently analyzed using Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM). The findings revealed that both nucleating agents expedited the crystallization process, diminishing incubation time and crystallization half-time. The most favorable outcomes were observed with 1 % EBS at 110 °C, exhibiting the fastest crystallization. XRD analysis indicated that the disordered α´ phase predominates at 80 °C, while more stable α phases form at 110 °C and 140 °C. The combination of 1 % nucleating agent and 110 °C facilitated the formation of densely packed crystalline lamellae. The nucleated PLA displayed a well-organized spherulitic morphology in alignment with Avrami modeling of DSC data. Higher nucleating agent concentrations resulted in smaller, more uniformly distributed crystalline domains. Incorporating OA or EBS in PLA processing can enhance properties, improve processability, and increase cost-efficiency, thereby improving PLA's competitiveness across diverse applications.

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Conference: SAMPE 2024

Publication Date: 2024/05/20

SKU: TP24-0000000030

Pages: 14

Price: $28.00