Effects of EVA Content on Properties of PP/EVA Blends and Melt-blown Nonwovens

Melt-blown nonwovens are widely used for their fine fibers and porous structure, but poor toughness and limited elongation prevent further application due to the characteristics of Polypropylene (PP), which is the main raw material of melt-blown nonwovens. In this work, ethylene-vinyl acetate copolymer (EVA) was added to PP in different proportions by using the blending method to improve the toughness and elongation of melt-blown nonwovens. Although the morphology of the blends showed a poor compatibility between PP and EVA, the thermal stability and rheological properties of the blends were excellent indicating a good spinnability from the consequent melt-blowing process. The fiber diameter of the nonwovens first increased then decreased with an increase of EVA content in the range of 5 % to 30 %. With the addition of EVA, the tensile strength and tensile modulus of nonwovens decreased and the elongation increased.