In order to manufacture the microporous, breathable films applicable to absorbent articles, LDPE, LLDPE, and HDPE/zeolite composite films filled with zeolite, uncoated and coated with stearic acid, were prepared. The stearic acid is verified as a coupling agent by how much effect it has on the various properties such as mechanical, thermal, morphological, and rheological measurements. The incorporation of stearic acid on the zeolite surface improved the flexibility of polymer matrices. In particular in the LLDPE and HDPE composites, the increase in the area of the air holes and decrease in the number of the air holes by merging among neighboring air holes was prominent upon higher filler loading, therefore resulted in enhanced modulus, elongation and impact properties. (c) 2006 Published by Elsevier Ltd.