Recycled polymer composition for manufacturing small to medium- sized container including HDPE recovered from secondary battery separator and small to medium-sized container manufactured therefrom

Patent metadata

Field	Value
Publication number	US-12129366-B2
Application number	US-202318326082-A
Country	US
Kind code	B2
Filing date	May 31, 2023
Priority date	Aug 19, 2022
Publication date	Oct 29, 2024
Grant date	Oct 29, 2024

Abstract

A polymer composition for manufacturing a small to medium-sized container and which includes a high-density polyethylene (HDPE) recovered from a secondary battery separator. A polymer composition having excellent processability may be prepared by recycling a secondary battery separator. The polymer composition may be molded to manufacture an environmentally friendly small to medium-sized container, such as a small to medium-sized container, having excellent flexural strength, elongation, impact strength, and environmental stress crack resistance.

First claim

What is claimed is:

1. A polymer composition for manufacturing a small to medium-sized container, wherein the polymer composition consists of i) high-density polyethylene (HDPE) and ii) optionally one or more additives, wherein the HDPE comprises:
a) a first HDPE; and
b) a second HDPE,
wherein the polymer composition satisfies Equation 1:

-
1

<

x
100

*

log
⁡
(

M
⁢

I
a

)

+

y
100

*

log
⁡
(

M
⁢

I
b

)

<
0

(

Equation
⁢

1

)

wherein:
x is a weight percentage of the first HDPE in the polymer composition for manufacturing a small to medium-sized container,
y is a weight percentage of the second HDPE in the polymer composition for manufacturing a small to medium-sized container,
MI a is a melt flow index (MFI) of the first HDPE,
MI b is an MFI of the second HDPE,
wherein MFI is measured in accordance with American Society for Testing and Materials standard ASTM D1238-10 (MFI measured at 190° C. at 2.16 kg),
wherein the first HDPE comprises HDPE recovered from a separator for a secondary battery or the manufacture of a secondary battery,
wherein the second HDPE has a density of about 0.930 g/cm 3 to about 0.970 g/cm 3 ,
wherein the second HDPE has a polydispersity index (PDI) of at least about 6, and
wherein the small to medium-sized container has a volume of less than 20 L.

2. The polymer composition for manufacturing a small to medium-sized container of claim 1 , wherein the first HDPE comprises a) HDPE recovered from a separator for a secondary battery, wherein the recovery of the separator comprises removing any inorganic coating layers thereon, or b) HDPE recovered during manufacture of a separator for a secondary battery, wherein the HDPE recovered is scrap HDPE, a separator end recovered after trimming, or a combination of both.

3. The polymer composition for manufacturing a small to medium-sized container of claim 1 , wherein the first HDPE has an MFI of about 0.01 g/10 min to 0.2 g/10 min.

4. The polymer composition for manufacturing a small to medium-sized container of claim 1 , wherein the first HDPE has a flexural modulus of about 5,000 kg/cm 2 to about 15,000 kg/cm 2 , a tensile strength at yield of about 200 kg/cm 2 to about 400 kg/cm 2 and an elongation at break of at least about 300%.

5. The polymer composition for manufacturing a small to medium-sized container of claim 1 , wherein the second HDPE has an MFI of about 0.25 g/10 min to about 1.5 g/10 min.

6. The polymer composition for manufacturing a small to medium-sized container of claim 1 , wherein the MFI of the first HDPE (MIa) and the MFI of the second HDPE (MIb) satisfy Equation 2:
0.15≤MI b −MI a ≤5  (Equation 2).

7. The polymer composition for manufacturing a small to medium-sized container of claim 1 , comprising about 20 wt. % to about 60 wt. % of the first HDPE and about 40 wt. % to about 80 wt. % of the second HDPE.

8. The polymer composition for manufacturing a small to medium-sized container of claim 1 , wherein the polymer composition satisfies Equation 1.1:

-
0.7

<

x
100

*

log
⁡
(

M
⁢

I
a

)

+

y
100

*

log
⁡
(

M
⁢

I
b

)

<

-

0.3
.

(

Equation

1.1

)

9. The polymer composition for manufacturing a small to medium-sized container of claim 1 , wherein the polymer composition has an MFI of about 0.1 g/10 min to about 0.5 g/10 min.

10. The polymer composition for manufacturing a small to medium-sized container of claim 1 , wherein the polymer composition has a tensile strength at yield of at least about 240 kg/cm 2 and an elongation at break of at least 300%.

11. The polymer composition for manufacturing a small to medium-sized container of claim 1 , wherein the polymer composition has an environmental stress crack resistance (ESCR) of 30 hours or more, as measured in accordance with ASTM D1693.

12. The polymer composition for manufacturing a small to medium-sized co

Assignees

• Sk Innovation Co Ltd
• Sk Geo Centric Co Ltd

Inventors

• Lee Hye Jin
• Park Jong Sang
• Hong Dae Sig
• Kang Sang Mook

Classifications

• C08L2207/20

  Recycled plastic · CPC title

• C08L2207/062

  HDPE · CPC title

• H01M50/417

  Polyolefins · CPC title

• Y02W30/62

  Plastics recycling; Rubber recycling · CPC title

• C08L2205/025

  containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure · CPC title