Plasticizers that enable flexible polyvinyl chloride (PVC) are usually combustible, restricting the application of PVC in fire-prone scenarios. In this context, intrinsically flame-retardant plasticizers displaying dual function continue to be the focus of intensive research. Despite their efficiency, the majority of these dual-functional plasticizers previously reported contain halogen elements, which, once ignited, emanate toxic and potentially carcinogenic substances, along with toxic gases and smoke, polluting the environment, damaging the biota, and threatening human health. Here, we report a strategy to obtain a halogen-free, intrinsically flame-retardant PVC bio-plasticizer that harnesses the phenolic hydroxyl of naturally occurring cardanol and covalent attachment of an organophosphate moiety. When combined with di-(2-ethylhexyl) phthalate (DOP), the organophosphate-containing cardanol is qualified as a co-plasticizer, while endowing the PVC materials with flame retardancy. Unlike inorganic flame-retardants, the engineered cardanol is compatible with PVC such that the mechanical properties of the PVC materials are not compromised. The rationale underlying the present effort may provide guidance for developing sustainable alternatives to halogen-containing plasticizers to address the sustainability challenge now confronting PVC industry.

启用柔性聚氯乙烯（PVC）的增塑剂通常是可燃的，从而限制了PVC在易火场景中的应用。在这种情况下，具有双重功能的内在阻燃增塑剂仍然是深入研究的重点。尽管效率高，但先前报道的大多数这些双功能增塑剂都含有卤素元素，一旦被点燃，它们会散发出有毒和潜在致癌物质，以及有毒气体和烟雾，污染环境，破坏生物群，并威胁人类健康。在这里，我们报告了一种获得无卤素，本质上阻燃的PVC生物增塑剂的策略，该生物增塑剂利用了天然腰果酚的酚羟基和有机磷酸酯部分的共价连接。当与邻苯二甲酸二（2-乙基己基）酯（DOP）结合使用时，含有机磷酸的腰果酚可作为助增塑剂，同时赋予PVC材料以阻燃性。与无机阻燃剂不同，工程制的腰果酚与PVC相容，因此不会损害PVC材料的机械性能。当前工作的基本原理可以为开发可持续的替代含卤素的增塑剂的方法提供指导，以解决目前PVC行业面临的可持续性挑战。