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Nanoscale zero-valent iron (nZVI) particles supported on a porous,semi-interpenetrating (semi-IPN),temperature-sensitive composite hydrogel (PNIPAm-PHEMA).nZVI@PNIPAm-PHEMA,was successfully synthesized and characterized by FT-IR,SM,EDS,XRD and the weighing method.The loading of nZVI was 0.1548 ± 0.0015 g/g and the particle size was 30-100 nm.NZVI was uniformly dispersed on the pore walls inside the PNIPAm-PHEMA.Because of the well-dispersed nZVI,the highly porous structure,and the synergistic effect of PNIPAm-PHEMA,nZVI@PNIPAm-PHEMA showed excellent reductive activity and wide pH applicability.95％ of 4-NP in 100 mL of 400 mg/L 4-NP solution with initial pH 3.0-9.0 could be completely reduced into 4-AP by about 0.0548 g of fresh supported nZVI at 18-25 ℃ under stirring (110 r/min) within 45 min reaction time.A greater than 99％ 4-NP degradation ratio was obtained when the initial pH was 5.0-9.0.The reduction of 4-NP by nZVI@PNIPAm-PHEMA was in agreement with the pseudo-first-order kinetics model with Kobs values of 0.0885-0.101 min-1.NZVI@PNIPAm-PHEMA was able to be recycled,and about 85％ degradation ratio of 4-NP was obtained after its sixth reuse cycle.According to the temperature sensitivity of PNIPAm-PHEMA,nZVI@PNIPAm-PHEMA exhibited very good storage stability,and about 88.9％ degradation ratio of 4-NP was obtained after its storage for 30 days.The hybrid reducer was highly efficient for the reduction of 2-NP,3-NP,2-chloro-4-nitrophenol and 2-chloro-4-nitrophenol.Our results suggest that PNIPAm-PHEMA could be a good potential carrier,with nZVI@PNIPAm-PHEMA having potential value in the application of reductive degradation of nitrophenol pollutants.