November 07, 2024 – In recent years, the heightened awareness towards environmental protection has brought biodegradable plastics like PLA into the spotlight. However, PLA’s brittleness, poor moisture barrier properties, and lack of heat resistance have limited its application scope. To tackle these challenges, Hainan University and Hainan Sino Biodegradable Materials Co., Ltd. have jointly applied for a new patent aimed at enhancing PLA’s overall performance through alloy blending.
The patent, titled “A PLA/PGA/(PBAT/ADR) Alloy and Its Preparation Method,” with publication number CN114605800A, ingeniously blends four materials—PLA, PGA, PBAT, and ADR—to successfully create a high-performance PLA/PGA/(PBAT/ADR) alloy. This novel material not only maintains good tensile toughness but also significantly improves the reinforcing properties, enhancing tensile performance, melt flowability, heat resistance, and moisture barrier properties.
During the preparation process, PBAT is first pre-mixed with the ADR chain extender. According to AsiaMB’s understanding, this step is typically completed on an internal mixer at a temperature of 160-230°C, with a rotation speed of 30-100 rpm, and a blending time of 5-20 minutes. This allows PBAT and ADR to thoroughly mix, modifying PBAT’s molecular structure and enhancing its performance. Subsequently, the obtained PBAT premix is melt-blended with PGA at a temperature generally ranging from 230-250°C, with a rotation speed of 30-100 rpm, and a blending time of 5-15 minutes. In this process, PGA uniformly disperses in the PBAT matrix, forming a PBAT/PGA blend.
The alloy exhibits exceptional performance. The addition of PGA significantly boosts the material’s strength and rigidity, resulting in a notable improvement in mechanical properties such as tensile strength and bending strength. Moreover, since both PBAT and PGA are biodegradable, their blend further enhances the degradation performance, enabling faster microbial decomposition under suitable environmental conditions. Additionally, PGA’s heat resistance contributes to better thermal stability and heat resistance of the blend. Importantly, PGA also improves the barrier properties, reducing the permeability of gases and water vapor, thereby broadening the application prospects of this material in packaging and other fields.
Overall, this PBAT/PGA material, prepared through a two-step blending method, combines the advantages of multiple materials, demonstrating excellent mechanical properties, degradation performance, thermal properties, and barrier properties. However, specific performance can still be influenced by factors such as raw material quality, blending ratios, and preparation processes. In the future, with continuous technological advancements and expanding applications, this novel biodegradable material is poised to play a crucial role in various sectors.