Novel polyolefin elastic fiber and manufacturing method thereof

The invention relates to a novel polyolefin elastic fiber and a manufacturing method thereof. The method comprises the following steps: a) providing a polyolefin elastomer mixture comprising at least one styrene block copolymer A, and at least one propylene polymer B and/or at least one propylene copolymer C by blending; b) adding a proper auxiliary agent into the polyolefin elastomer mixture, and then melting and granulating to obtain the uniform mixture; and c) carrying out melt spinning on the uniform mixture to obtain the novel polyolefin elastic fiber, wherein the styrene/rubber ratio of the styrene block copolymer A is between 10: 90 and 30: 70; the density of the propylene polymer B is 0.900-0.915 g/cm < 3 >, and the melting point of the propylene polymer B is gt; the temperature is 160 DEG C; the density of the propylene copolymer C ranges from 0.855 g/cm < 3 > to 0.899 g/cm < 3 >; the content of the styrene block polymer A is 30-90% by weight, and the total content of the propylene polymer B and/or t