CPC B01D 69/02 (2013.01) [B01D 53/228 (2013.01); B01D 67/0027 (2013.01); B01D 69/088 (2013.01); B01D 71/261 (2022.08); B01D 71/262 (2022.08); B01D 19/0031 (2013.01); B01D 2053/224 (2013.01); B01D 2325/022 (2013.01); B01D 2325/04 (2013.01)] | 19 Claims |
1. An asymmetric hollow fiber membrane comprising:
a porous substrate having a plurality of pores, wherein the porous substrate includes
a first semi-crystalline thermoplastic polyolefin (co)polymer comprising polypropylene, polyethylene or a combination thereof and
a melting alpha nucleating agent or a gamma nucleating agent in an amount effective to achieve nucleation; and
a skin layer overlaying the porous substrate, wherein the skin layer includes a second semi-crystalline thermoplastic polyolefin (co)polymer derived by polymerizing
at most 98 wt. % of 4-methyl-1-pentene monomer with at least 2 wt. % of linear or branched alpha olefin monomers selected from the group consisting of ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, isobutylene, vinylcyclohexane, 3-ethyl-1-pentene, 1,3-methyl-1-pentene, cyclobutene, cyclopentane, 2-norbornene, 3-methyl-2-norbornene, 5-methyl-2-norbornene, tetracyclododecene, methyltetracyclo-dodecene, dimethyltetracyclo-dodecene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-eicosene, or a combination thereof,
optionally wherein the first thermoplastic polyolefin (co)polymer is compositionally different from the second thermoplastic polyolefin (co)polymer.
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