Internally lubricated polymer compositions containing a styrene- and/or polyphenylene ether-containing polymer, an olefin-containing polymer, and a compatibilizer are provided. The olefin-containing polymer, which is present in the compositions in about 3 to about 30 weight percent, provides internal lubrication and improves the tribological properties of the compositions compared with the styreneor polyphenylene ether-containing polymer alone, as determined by wear measurements. Preferred compositions exhibit wear factors less than about 130 x 10<-11 >mm<5>/Pa-m. A preferred composition includes a blend of polystyrene/polyphenylene ether, linear low density polyethylene, and styreneethylene-butadiene-styrene. Methods are also provided for improving tribological properties of styrene- and/or polyphenylene ether-containing base polymers by incorporating into the base polymers at least one olefin-containing polymer and at least one compatibilizer, or by incorporating at least one substantially halogen-free internal lubricant.