Meltblown Elastic Nonwovens from Specialty Polyolefin Elastomers

摘要

Specialty Polyolefin Elastomers (SPE) are a new generation of metallocene catalyst-based polymers endowed with isotactic propylene crystallinity. They can be processed in conventional spunmelt equipment to produce elastic nonwoven fabrics. For meltblown applications, SPE resins were developed at a nominal melt flow rate (MFR) of either 200 or 300 g/10 min for processability considerations. The crystallinity of the SPE resins can be adjusted through variations in the comonomer content, which results in nonwovens with varying levels of elasticity. In this paper, the nonwoven characteristics of SPE A polymer (lower crystallinity, 200 MFR) and SPE B polymer (higher crystallinity, 300 MFR) are characterized as a function of process parameters such as die to collector distance (DCD), air gap settings, and fabric basis weight. Formulations of these SPE resins, blended with conventional meltblown PP (1600 MFR) over a wide range of blend compositions, are also discussed in this work.