Petrol and biochemical plasticizers are added to poly(vinyl alcohol) (PVA) to improve its processability while tuning its moisture sensitivity. But those additives often reduce the mechanical performance of PVA products. In this study, the antiplasticization and properties of PVA containing additives from biorenewable sources are studied. PVA fibers are gel‐spun having up to 3 wt% glucarate salts and 30% lignin. Glucarate lowers the gel melting temperature of PVA and increases fiber draw ratio. Further, glucarate enhances the mechanical performance of PVA beyond that of neat fibers. Interestingly, the combination of lignin and glucarate causes phase separation among fiber—a PVA/glucarate phase as the fiber core and lignin/PVA phase as the fiber shell. Neat PVA partially dissolves in 85 °C water; whereas, fibers containing glucarate and/or lignin resist dissolution. Thus, the combination of glucarate and lignin can induce high strength and moisture resistance, which are desirable industrial fiber properties.