A spacer for insulated glazings includes a polymeric main body including two pane contact surfaces, a glazing interior surface, an outer surface, and a cavity, wherein the polymeric main body contains a thermoplastic polymer as a base material at a proportion of 30 wt.-% to 70 wt.-%, as an elastomeric additive, a thermoplastic elastomer, and/or a thermoplastic terpolymer having an elastomeric component at a proportion of 0.5 wt.-% to 20 wt.-% in total, and a reinforcing agent at a proportion of 20 wt.-% to 45 wt.-%, the thermoplastic polymer as a base material includes a styrene-based polymer, and the polymeric main body has a foamed pore structure.