US 12,240,926 B2
Composition for encapsulant film comprising ethylene/alpha-olefin copolymer and encapsulant film comprising the same
Jin Sam Gong, Daejeon (KR); Eun Jung Lee, Daejeon (KR); Young Woo Lee, Daejeon (KR); Jung Ho Jun, Daejeon (KR); and Jin Kuk Lee, Daejeon (KR)
Assigned to LG Chem, Ltd., Seoul (KR)
Appl. No. 17/630,216
Filed by LG Chem, Ltd., Seoul (KR)
PCT Filed Dec. 17, 2020, PCT No. PCT/KR2020/018594
§ 371(c)(1), (2) Date Jan. 26, 2022,
PCT Pub. No. WO2021/210756, PCT Pub. Date Oct. 21, 2021.
Claims priority of application No. 10-2020-0046029 (KR), filed on Apr. 16, 2020; and application No. 10-2020-0177692 (KR), filed on Dec. 17, 2020.
Prior Publication US 2022/0282010 A1, Sep. 8, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. C08F 210/16 (2006.01); C08F 210/02 (2006.01); C08F 210/08 (2006.01)
CPC C08F 210/08 (2013.01) [C08F 210/16 (2013.01); C08F 210/02 (2013.01); C08F 2500/03 (2013.01); C08F 2500/08 (2013.01); C08F 2500/34 (2021.01)] 15 Claims
 
1. A composition for an encapsulant film, the composition comprising an ethylene/alpha-olefin copolymer satisfying the following conditions (a) to (d):
(a) a density is 0.85 to 0.89 g/cc;
(b) a molecular weight distribution is 1.5 to 2.3;
(c) a melting temperature is 85° C. or less; and
(d) a free volume proportional constant (C2) derived from Equations 1 and 2 is 600 or less:

OG Complex Work Unit Math
in Formula 1,
η0(T) is a viscosity (Pa·s) of a copolymer measured at an arbitrary temperature of T (K) using ARES-G2 (Advanced Rheometric Expansion System),
η0(Tr) is a viscosity (Pa·s) of a copolymer measured at a reference temperature of Tr (K) using the ARES-G2, and
aT is a shift factor of the arbitrary temperature of T (K) with respect to the reference temperature of Tr(K), and obtained from Equation 1,

OG Complex Work Unit Math
in Formula 2,
C1 is a free volume inverse proportional constant,
C2 is a free volume proportional constant (K), and
C1 and C2 are intrinsic constants of the ethylene/alpha-olefin copolymer, and obtained from Equation 2.