Recyclable, biodegradable, and industrially compostable extruded foams, and methods of manufacturing the same
A process for producing a flexible foam includes introducing a masterbatch material into an extruder, the masterbatch material consisting essentially of one or more thermoplastic polymers that are recycled, recyclable, biodegradable, and/or compostable, mixing an inert gas with the masterbatch material, extruding the masterbatch material through the extruder to form a polymer melt, passing the polymer melt through a die to form an extrudate, and allowing the extrudate to expand into a foam.
1 . A process for producing a flexible foam, the process comprising:
introducing a masterbatch material into a first extruder, the masterbatch material comprises one or more thermoplastic polymers that are recycled, recyclable, biodegradable, and/or compostable;
melting the masterbatch material in the first extruder to form a polymer melt;
mixing an inert gas with the polymer melt in the first extruder;
extruding the polymer melt mixed with inert gas from the first extruder into a second extruder;
passing the polymer melt mixed with inert gas from the second extruder through a die to form an extrudate, wherein the polymer melt mixed with inert gas is pumped from the second extruder through the die via a melt pump disposed between the second extruder and the die; and
allowing the extrudate to expand into a foam.
2 . The process of claim 1 , wherein the inert gas is carbon dioxide.
3 . The process of claim 1 , wherein the inert gas is nitrogen.
4 . The process of claim 1 , wherein the one or more thermoplastic polymers comprises a polyamide or a polyamide copolymer.
5 . The process of claim 1 , wherein the one or more thermoplastic polymers comprises a polyamide selected from the group consisting of: polyether block amide (PEBA), polyamide 6, polyamide 6/6-6, polyamide 12, or a blend containing one or more thereof.
6 . The process of claim 1 , wherein the one or more thermoplastic polymers comprises a polyesters or a polyester copolymer.
7 . The process of claim 1 , wherein the one or more thermoplastic polymers comprises a polymer selected from the group consisting of: polybutylene adipate terephthalate (PBAT), polylactic acid (PLA), poly(L-lactic acid) (PLLA), poly(butylene adipate-co-terephthalate) (PBAT), polycaprolactone (PCL), polyhydroxy alkanoate (PHA), polyhydroxybutyrate (PHB), polybutylene succinate (PBS), polybutylene succinate adipate (PBSA), polybutylene adipate (PBA), thermoplastic starch (TPS), and a blend containing one or more thereof.
8 . The process of claim 1 , wherein the one or more thermoplastic polymers comprises one or more recycled polymer materials.
9 . The process of claim 1 , wherein the one or more thermoplastic polymers comprises of one or more bio-derived polymers.
10 . The process of claim 9 , wherein the one or more bio-derived polymers comprises a bio-derived PBAT.
11 . The process of claim 1 , wherein the inert gas is mixed with the polymer melt as a supercritical fluid.
12 . The process of claim 11 , wherein the polymer melt and the supercritical fluid are mixed to form a single-phase solution in the first extruder.
13 . The process of claim 12 , wherein extruding the polymer melt mixed with inert gas from the first extruder into the second extruder comprises extruding the single-phase solution from the first extruder into the second extruder.
14 . The process of claim 1 , wherein the polymer melt mixed with inert gas is extruded from the first extruder into the second extruder via a pipe connecting the first extruder to the second extruder.
15 . The process of claim 1 , wherein the second extruder comprises one or more extrusion screws that are cooled.
16 . The process of claim 1 , wherein the extrudate is formed into a flat sheet.
17 . The process of claim 1 , wherein the one or more thermoplastic polymers consists of PBAT.
18 . A process for producing a flexible foam, the process comprising:
introducing a masterbatch material into a first extruder, the masterbatch material consisting essentially of one or more thermoplastic polymers that are recycled, recyclable, biodegradable, and/or compostable, wherein the one or more thermoplastic polymers consists of PBAT;
melting the masterbatch material in the first extruder to form a polymer melt;
mixing an inert gas with the polymer melt in the first extruder;
extruding the polymer melt mixed with inert gas from the first extruder into a second extruder;
passing the polymer melt mixed with inert gas from the second extruder through a die to form an extrudate; and
allowing the extrudate to expand into a foam.
19 . The process of claim 18 , wherein the inert gas is mixed with the polymer melt as a supercritical fluid.
20 . The process of claim 18 , wherein the extrudate is formed into a flat sheet.