Whole and split wheat straws (WS) with length up to 10 cm have been used with polypropylene (PP) webs to make lightweight composites with properties superior to jute-PP composites with the same density. The effect of WS concentration, WS length, and split configuration (half, quarter, and mechanically split) on flexural and tensile properties of the composites has been investigated. The sound absorption properties of composites from whole straw and split straw have been studied. Compared with whole WS-PP composites, mechanically split WS-PP composites have 69% higher flexural strength, 39% higher modulus of elasticity, 18% higher impact resistance properties, 69% higher tensile strength and 26% higher Young's modulus. Compared with jute-PP composites, mechanically split WS-PP composites have 114% higher flexural strength, 38% higher modulus of elasticity, 10% higher tensile strength, 140% higher Young's modulus, better sound absorption properties and 50% lower impact resistance. (C) 2009 Elsevier Ltd. All rights reserved.