MULTILAYER POLYMER FILMS FORMED FROM POST-CONSUMER RECYCLING MATERIALS WITH IMPROVED MECHANICAL AND PHYSICAL PROPERTIES

Abstract

A multi-layer film is described that has at least a skin and core layers, wherein the core layer comprises post-consumer recycled (PCR) polyethylene polymer.

Claims

1. A multi-layer film comprising at least two layers, the skin layer comprising a polyolefin having a density of from about 0.915 g/cc to 0.950 g/cc and a melt index of from about 0.5g to about 3 g/10 min at 190 C./2.16 kg, and a core layer comprising post-consumer recycled (PCR) low density polyethylene polymer.

2. The multi-layer film of claim 1, wherein the outer skin layer of the multi-layer film comprises at least one of a low-density polyethylene, a metallocene catalyzed polyethylene (mPE), a linear low-density polyethylene (LLDPE), a low-density polyethylene (LDPE), a medium-density polyethylene (MDPE), a high-density polyethylene (HDPE), a virgin polyolefin copolymers, a post-consumer recycled polyethylene polymer, or a postindustrial recycled polyethylene polymer.

3. The multi-layer film of claim 1, wherein the film further comprises three layers, wherein first and third skin layers surround and enclose a second, core layer.

4. The multi-layer film of claim 3, wherein the second, core layer of post-consumer recycled linear low density polyethylene polymer having at least 0.25 melt flow index (M FI).

5. The multi-layer film of claim 3, wherein the second, core layer comprises about 50% post-consumer recycled (PCR) content.

6. The multi-layer film of claim 1, wherein the film further comprises five layers wherein first and third skin layers surround a second, core layer comprising post-consumer recycled linear low density polyethylene polymer and the third and fifth skin layers surround a fourth, core layer comprising post-consumer recycled linear low density polyethylene polymer.

7. The multi-layer film of claim 1, wherein the film further comprises seven layers wherein first and third skin layers surround a second, core layer comprising post-consumer recycled linear low density polyethylene polymer, the third and fifth skin layers surround a fourth, core layer comprising post-consumer recycled linear low density polyethylene polymer; and the fifth and seventh skin layers surround a sixth, core layer comprising post-consumer recycled linear low density polyethylene polymer.

8. The multi-layer film of claim 1, wherein the outer skin layer comprises a recycled linear low-density polyethylene (LLD PE), a low-density polyethylene (LDPE), a medium-density polyethylene (M D PE), a high-density polyethylene (HDPE), a post-consumer recycled polyethylene polymer, or a postindustrial recycled polyethylene polymer.

9. The multi-layer film of claim 8, wherein the overall post-consumer recycled content ranges from 20% to 90%

10. The multi-layer film of claim 3, wherein the overall film thickness ranges from about 20 mil to 70 mils.

11. An article formed from the multi-layer film of claim 11, wherein the article is a pond liner.

12. A method of making a multi-layer film comprising at least two layers, the film characterized by a skin layer comprising a polyolefin having a density of from about 0.915 g/cc to 0.950 g/cc and a melt index of from about 0.5g to about 3 g/10 min at 190 C./2.16 kg, and a core layer comprising about 50% post-consumer recycled (PCR) low density polyethylene polymer, and the method comprising a blown film process.

Description

EXAMPLES

Formation of Pond Liners With Post-Consumer Recycled (PCR) Multilayer Films

[0029] Characteristics of which are each described in Table 1. The 60 mil with 40% Mixed PCR (Core with 5% K 306 and 5% FM); the 40 mil with 50% Mixed PCR (Core), the 30 mil with 50% Mixed PCR (Core) are described Table 1. The 0% PCR 60-mil film is the control film for the 60-mil 40% mixed PCR film.

TABLE-US-00001 TABLE 1 film properties 30-mil 40-mil 60-mil 20% 50% 20% 50% 40% Test White Mixed White Mixed 0% Mixed Property Method PCR* PCR* PCR* PCR* PCR* PCR* Thickness, mils ASTMD 28 29 37 39 56 60 5199 Density, g/cc ASTMD 0.942 0.939 0.942 792 % Carbon Black(CB) Content ASTMD 2.21 3.26 2.58 3.39 2.8 2.81 4218 Tensile Properties Yield Strength, MD/TD, ppi ASTMD 42/44 52/53 57/58 69/71 149/147 109/110 Break Strength, MD/TD, ppi 6693 112/108 19/114 143/147 155/150 247/244 231/235 Yield Elongation(%), MD/TD 23/24 29/22 28/25 25/19 20/21 25/22 Break Elongation(%), MD/TD 725/805 748/793 741/865 743/776 798/745 757/810 Puncture Strength, lbf ASTMD 59 62.6 72 80 131 103 4833 Tear Resistance, MD/TD, lbf ASTMD 10/19 18.9/20.2 25/24 29/29 48/48 44/45 1004 *PCR in core only

[0030] As can be seen in the Table that films comprising at least 50% PCR within the core structure are usable to form multi-layer films of a thickness between above 20 mils and 70 mils. Y et even further, the tensile, density and tear resistant properties of the multi-layer films according to the invention are on par with commercially available multi-layer films lacking the PCR of the invention.