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

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 container of claim 1 , wherein the polymer composition has an Izod impact strength of 10 kgf cm/cm measured at a temperature of at least about 23±2° C. and a flexural modulus of at least about 7,500 kg/cm 2 .

13. A small to medium-sized container comprising the polymer composition for manufacturing a small to medium-sized container of claim 1 , wherein the small to medium-sized container has a volume of less than 20 L.

14. A method of manufacturing a small to medium-sized container, the method comprising

(a) obtaining high-density polyethylene (HDPE) recovered from a separator for a secondary battery, wherein the HDPE recovered from the separator for a secondary battery is a first HDPE;

(b) combining the first HDPE and a second HDPE to manufacture a pre-production polymer, and

(c) subjecting the pre-production polymer to conditions effective to generate the small to medium-sized container, wherein the first HDPE and second HDPE are selected to satisfy 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 pre-production polymer;

y is a weight percentage of the second HDPE in the pre-production polymer;

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 second HDPE has a density of about 0.930 g/cm 3 to about 0.970 g/cm 3 , and

wherein the small to medium-sized container has a volume of less than 20 L.

15. The method of manufacturing the small to medium-sized container of claim 14 , wherein

a) the first HDPE comprises an inorganic coating layer and the method further comprises removing the inorganic coating layers thereon, or

b) the first HDPE is scrap HDPE, a separator end recovered after trimming, or a combination of both.

16. The method of manufacturing the small to medium-sized container of claim 14 , wherein the conditions effective to generate the small to medium-sized container comprise one or more of injection-molding, blow-molding, and profile extrusion.

17. The method of claim 14 , wherein combining the first HDPE and a second HDPE to manufacture a pre-production polymer comprises combining the first HDPE and second HDPE with one or more additives selected from the group consisting of an antioxidant, a UV absorber, a UV stabilizer, a lubricant, a pigment, a colorant, a filler, a plasticizer, a flow agent, an antistatic agent, a flame retardant, a slap agent, and an anti-block agent.

18. 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 and an MFI of about 0.25 g/10 min to about 1.5 g/10 min, and

wherein the small to medium-sized container has a volume of less than 20 L.