US 12,351,658 B2
Polypropylene resin, polypropylene fiber and method for preparing the same
Seong Min Chae, Daejeon (KR); Hyunsup Lee, Daejeon (KR); Kyung Seop Noh, Daejeon (KR); Heekwang Park, Daejeon (KR); and Jihwa Ye, Daejeon (KR)
Assigned to LG Chem, Ltd., Seoul (KR)
Appl. No. 17/435,136
Filed by LG Chem, Ltd., Seoul (KR)
PCT Filed Dec. 4, 2020, PCT No. PCT/KR2020/017652
§ 371(c)(1), (2) Date Aug. 31, 2021,
PCT Pub. No. WO2021/112623, PCT Pub. Date Jun. 10, 2021.
Claims priority of application No. 10-2019-0160109 (KR), filed on Dec. 4, 2019; and application No. 10-2020-0167775 (KR), filed on Dec. 3, 2020.
Prior Publication US 2022/0135715 A1, May 5, 2022
Int. Cl. C08F 110/06 (2006.01); C07F 17/00 (2006.01); D01D 5/08 (2006.01); D01F 6/06 (2006.01)
CPC C08F 110/06 (2013.01) [C07F 17/00 (2013.01); D01D 5/08 (2013.01); D01F 6/06 (2013.01); C08F 2420/00 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A polypropylene resin comprising a homopolypropylene polymer and meeting the following conditions of i) to iv):
i) an average particle diameter is 1,200 μm to 2,500 μm,
ii) a melt index measured at 230° C. with a load of 2.16 kg in accordance with ASTM D1238 is 1,700 g/10 min to 3,500 g/10 min,
iii) a crystallization on set temperature (T1) is 127° C. or more, wherein the crystallization on set temperature (T1) is an initial temperature at a point where a viscosity change ratio represented by Equation 1 is 190 or more,
Viscosity change ratio=V2(T2)/V1(T1)  [Equation 1]
In Equation, V1(T1) and V2(T2) are complex viscosities (Pa·s) measured at T1 and T2, respectively, while reducing the temperature of a polypropylene resin from 180° C. at 1° C./min under a shear rate of 1 s−1,
T1 is a crystallization on set temperature, and
T2 is a temperature 3° C. lower than the crystallization on set temperature (T1),
wherein the complex viscosities are measured using advanced rheometric expansion system (ARES), and
iv) a molecular weight distribution is 2.2 to 2.4.