Spunbondmeltblownspunbond

Spunbondmeltblownspunbond, commonly abbreviated as SMS, is a tri-layer nonwoven fabric structure consisting of a spunbond outer layer, a central meltblown barrier layer, and another spunbond outer layer. It is most often produced from polypropylene and is widely used in protective and filtration applications due to its combination of strength, barrier properties, and breathability.

The outer layers are spunbond nonwovens formed by extruding and drawing filaments into a web, which is then bonded to create a sturdy yet soft fabric. The middle layer is a meltblown nonwoven produced by extruding polymer through small nozzles and attenuating the filaments with high-velocity air to form very fine fibers. The three layers are laminated together, typically by thermal bonding or adhesive bonding, to form a single sheet. Typical SMS constructions use lightweight outer layers and a relatively more porous middle layer, with overall basis weights commonly in the range of a few tens of grams per square meter per layer, resulting in a total typical weight around 50–120 g/m2 depending on application.

Properties of SMS fabrics include barrier performance against fluids and particulates, combined with reasonable air permeability and softness. The meltblown middle layer provides filtration efficiency, while the outer spunbond layers contribute mechanical strength and handle. Variants and performance can be tuned by adjusting the weights of the outer and middle layers, as well as the polymers used.

Applications include medical and protective textiles such as disposable surgical gowns, surgical masks, and filtration media. Environmental considerations focus on polymer choice and end-of-life disposal, as SMS fabrics are predominantly polypropylene and designed for single-use items.