Biaxially oriented polyamide-6 (BOPA) film has been widely used in many packaging applications. However, the BOPA film with excellent toughness is still required when utilizing in the field of soft-packaged lithium-ion batteries, pharmaceutical blister packaging, or frozen food packaging especially for vacuum packaging of irregular-shaped food products. The purpose of this study was to improve the toughness of BOPA films by toughening with poly(ether block amide) (PEBA) (BOPA/PEBA films) based on the simultaneous biaxial stretching technology. The crystal structure, morphology, optical properties, barrier, and mechanical properties of BOPA/PEBA films were investigated. The results showed that the incorporation of PEBA into BOPA films slightly decreased the melting temperature and crystallinity of PA6, and the BOPA/PEBA films exhibited only α-form crystals and no preferential orientation in the machine direction (MD) and transition direction (TD). The morphological observation showed that higher addition of PEBA led to the formation of microvoids due to the poor compatibility between PA6 and PEBA. As a result, the transmittance and oxygen barrier properties of the BOPA/PEBA films decreased. In addition, mechanical analysis suggested that the addition of PEBA could effectively improve the toughness of BOPA film.

中文翻译：

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聚醚嵌段酰胺增韧双轴取向聚酰胺6薄膜的晶体结构、形态和机械性能

双向拉伸聚酰胺 6 (BOPA) 薄膜已广泛用于许多包装应用。然而，在软包锂领域使用时，仍然需要具有优异韧性的BOPA薄膜——离子电池、医药泡罩包装或冷冻食品包装，特别适用于不规则形状食品的真空包装。本研究的目的是通过基于同时双轴拉伸技术的聚（醚嵌段酰胺）（PEBA）（BOPA/PEBA 薄膜）增韧来提高 BOPA 薄膜的韧性。研究了 BOPA/PEBA 薄膜的晶体结构、形貌、光学性能、阻隔性和机械性能。结果表明，PEBA 掺入 BOPA 薄膜后，PA6 的熔化温度和结晶度略有降低，BOPA/PEBA 薄膜仅呈现 α 型晶体，在纵向 (MD) 和过渡方向 (TD) 上没有择优取向. 形态观察表明，由于 PA6 和 PEBA 之间的相容性差，PEBA 的添加量较高导致微孔的形成。结果，BOPA/PEBA 薄膜的透光率和氧气阻隔性能下降。此外，力学分析表明，PEBA的加入可以有效提高BOPA薄膜的韧性。