Accessing enhanced mechanical properties and processability with branched and cross-linked biodegradable polymers

具有可控结构和性能的可生物降解聚合物在过去几年中引起了人们的浓厚兴趣，并已被应用于从包装、农业材料到微电子的各种应用和产品。然而，现有的可生物降解聚合物产品的物理性能范围有限，这限制了它们在需要增强机械性能的领域的应用。例如，聚乳酸等线性可生物降解聚合物的熔体强度和脆性较差，而聚己内酯的熔点较低，限制了其用途。在这些聚合物中加入支化有望提高其机械性能，使其可与许多石油基塑料相媲美，众所周知，许多石油基塑料的支化度很容易改变，从而获得不同密度和机械性能的聚合物材料。在生物可降解聚合物中引入类似的支化结构是开发下一代绿色材料的重要一步。

Biodegradable polymers with controlled structure and properties have been of intense interest in the past few years and have been used in applications and products ranging from packaging and agricultural materials to microelectronics. However, existing biodegradable polymer products suffer from a limited scope of physical properties, which limit their applications in areas where enhanced mechanical properties are necessary. For example, linear biodegradable polymers such as polylactides have poor melt strength and brittleness while polycaprolactones have low melting points that limit their usefulness. Incorporating branches in these polymers is expected to enhance their mechanical properties and make them comparable to those of many petroleum-based plastics, which are known to have easily modified degrees of branching to give polymeric materials of variable densities and mechanical properties. Introducing comparable branched structures into biodegradable polymers in is an important step for developing the next generation of green materials.