Method for producing temperature resistant nonwovens

摘要

Temperature resistant multilayer composites, methods for making same, and articles made therefrom. The method can include extruding one or more polyolefin polymers having a MFR from less than 90 dg/min through at least one die having a plurality of nozzles to form a plurality of continuous fibers, at least one die operating at a melt pressure from greater than 500 psi (3447 kPa) to form at least one elastic meltblown layer; adhering the at least one elastic meltblown layer to at least one extensible layer to form a multilayer composite; and at least partially crosslinking the elastic meltblown layer or the extensible layer or both.

主权项

1. A method for forming a temperature resistant multilayer composite, comprising:
extruding a blend of one or more propylene-based elastic resins and a coagent through one or more dies having a plurality of nozzles to form a first plurality of continuous fibers, wherein the first plurality of continuous fibers form a first meltblown layer, where the propylene-based elastic resin is a random copolymer and comprises 80 to 95 wt % propylene and has a heat of fusion less than 75 J/g and a MFR of greater than 50 dg/min, and where the coagent is selected from multifunctional acrylates and methacrylates, functionalized polybutadiene resins, functionalized cyanurate, and allyl isocyanurate; extruding one or more extensible resins through one or more dies simultaneously or nearly simultaneously with the one or more elastic resins to form a second plurality of continuous fibers, wherein the second plurality of continuous fibers form a second layer; wherein the first meltblown layer and the second layer contact each other while the first meltblown layer is still forming, such that the plurality of continuous fibers are still in a melt or partial melt state when contacting the at least one extensible resin, thereby forming a multilayer composite; and exposing the multilayer composite to electron beam radiation having an e-beam dose of about 200 kGy or less, thereby crosslinking the first meltblown layer and the second layer.