US 11,668,033 B2
High quality melt-blown webs with improved barrier properties
Lisa Maria Steiner, Königswiesen (AT); Gerhard Hubner, Breitenaich (AT); Jingbo Wang, Engerwitzdorf (AT); Markus Gahleitner, Neuhofen/Krems (AT); Georg Grestenberger, St. Peter in der AU (AT); and Joachim Fiebig, Engerwitzdorf (AT)
Assigned to BOREALIS AG, Vienna (AT)
Appl. No. 16/304,779
Filed by BOREALIS AG, Vienna (AT)
PCT Filed Jun. 8, 2017, PCT No. PCT/EP2017/063902
§ 371(c)(1), (2) Date Nov. 27, 2018,
PCT Pub. No. WO2017/216017, PCT Pub. Date Dec. 21, 2017.
Claims priority of application No. 16174131 (EP), filed on Jun. 13, 2016.
Prior Publication US 2020/0325607 A1, Oct. 15, 2020
Int. Cl. C08F 8/50 (2006.01); D04H 3/007 (2012.01); D04H 3/16 (2006.01); D04H 1/56 (2006.01); D04H 1/4291 (2012.01); D04H 1/544 (2012.01)
CPC D04H 1/56 (2013.01) [C08F 8/50 (2013.01); D04H 1/4291 (2013.01); D04H 1/544 (2013.01); D04H 3/007 (2013.01); D04H 3/16 (2013.01); C08F 2810/10 (2013.01)] 5 Claims
OG exemplary drawing
 
1. Melt-blown web comprising melt-blown fibers made of at least 95 wt % of a polypropylene composition comprising:
(A) a polypropylene homopolymer, wherein the polypropylene homopolymer comprises at least 95 wt % of the polypropylene composition, and
(B) optionally a polymeric nucleating agent,
wherein the melt-blown web shows an integral ratio [Rv], being defined as ratio of the integral value specifying the area under the peak with the chemical shift at 4.77 ppm of a 1H NMR spectrum to the integral value specifying the area under the peak with the chemical shift at 4.70 ppm 1H NMR spectrum, of 0.95 to 1.03, whereby the 1H NMR spectrum was determined by solution-state 1H-NMR spectroscopy,
wherein the polypropylene composition has been prepared by visbreaking with at least one compound (C) being capable of thermally decomposing into carbon-based free radicals of formula (I) or (II) by breaking at least one single bond:

OG Complex Work Unit Chemistry
wherein in these formulas each of
R1, R2 R3, R4, R5 and R6 can be independently selected from hydrogen, substituted or unsubstituted straight chain, branched or cyclic saturated or mono-unsaturated hydrocarbons with 1 to 12 C-atoms, substituted or unsubstituted aromatic hydrocarbons with 5 to 12 C-atoms or carboxylate groups COOX, with X being a C1-C6-alkyl group,
whereby at least one of R1, R2 R3, R4, R5 or R6 is a substituted or unsubstituted aromatic hydrocarbon with 5 to 12 C-atoms.