Biodegradable, industrially compostable, and recyclable injection molded microcellular flexible foams
This document discloses a process for manufacturing recyclable injection molded microcellular foams for use in, footwear components, seating components, protective gear components, and watersport accessories. The process includes the steps of providing a thermoplastic polymer which comprises at least one monomer derived from depolymerized post-consumer plastic, inserting a fluid into a barrel of a molding apparatus. The fluid is introduced under temperature and pressure conditions to produce a super critical fluid. The process further includes mixing the thermoplastic polymer and super critical fluid so as to create a single phase solution, and injecting the single phase solution into a mold of an injection molding machine under gas counter pressure. The process further includes foaming the single phase solution by controlling the head and temperature conditions within the mold.
1. A method for manufacturing a recyclable flexible foam molded product comprising:
providing a thermoplastic polymer precursor comprising repolymerized monomers derived from depolymerized post-consumer or post-industrial plastic;
inserting a fluid into a barrel of a molding apparatus under temperature and pressure conditions to produce a super critical fluid;
mixing the thermoplastic polymer precursor and the super critical fluid to create a single phase solution;
injecting the single phase solution into a mold of an injection molding machine wherein the mold is under gas counter pressure; and
foaming the single phase solution by controlling temperature and pressure conditions within the mold.
2. The method in accordance with claim 1 , wherein at least 40% of the thermoplastic polymer precursor comprises the repolymerized monomers derived from depolymerized post-consumer or post-industrial plastic.
3. The method in accordance with claim 2 , wherein at least 60% of the thermoplastic polymer precursor comprises the repolymerized monomers derived from depolymerized post-consumer or post-industrial plastic.
4. The method in accordance with claim 3 , wherein 90% or more of the thermoplastic polymer precursor comprises the repolymerized monomers derived from depolymerized post-consumer plastic.
5. The method in accordance with claim 1 , wherein the monomers comprise caprolactam.
6. The method in accordance with claim 1 , wherein the thermoplastic polymer precursor comprises a polyamide based thermoplastic elastomer.
7. The method in accordance with claim 6 , wherein the thermoplastic polymer precursor comprises a copolymer including at least one caprolactam monomer.
8. The method in accordance with claim 1 , further including the step of recycling a flexible foam by depolymerizing the flexible foam into one or more monomers.
9. The method in accordance with claim 8 , wherein the flexible foam is depolymerized into caprolactam.
10. A method for producing a recyclable foam, the method comprising:
providing a non-crosslinked thermoplastic polymer blend into a molding apparatus, the non-crosslinked thermoplastic polymer blend comprising repolymerized monomers derived from depolymerized post-consumer or post-industrial plastic;
mixing the non-crosslinked thermoplastic polymer blend with supercritical nitrogen or supercritical carbon dioxide to produce a thermoplastic foamed melt;
applying a gas counter pressure to the thermoplastic foamed melt;
expanding the thermoplastic foamed melt within a mold of the molding apparatus; and
cooling the expanded thermoplastic foamed melt.
11. The method of claim 10 , wherein the non-crosslinked thermoplastic polymer blend comprises caprolactam or polyether block amide polymer.
12. A recyclable foam produced by the method of claim 10 .
13. The method of claim 10 , wherein the non-crosslinked thermoplastic polymer blend comprises caprolactam.
14. The method of claim 10 , wherein at least 40% of the non-crosslinked thermoplastic polymer blend comprises the repolymerized monomers derived from depolymerized post-consumer or post-industrial plastic.
15. The method of claim 10 , wherein at least 60% of the non-crosslinked thermoplastic polymer blend comprises the repolymerized monomers derived from depolymerized post-consumer or post-industrial plastic.
16. The method of claim 10 , wherein at least 90% of the non-crosslinked thermoplastic polymer blend comprises the repolymerized monomers derived from depolymerized post-consumer or post-industrial plastic.
17. A method for producing a recyclable foam, the method comprising:
providing a non-crosslinked thermoplastic polymer blend into a molding apparatus, the non-crosslinked thermoplastic polymer blend comprising polyether-block-amide (PEBA) comprising repolymerized monomers derived from depolymerized post-consumer or post-industrial plastic;
mixing the non-crosslinked thermoplastic polymer blend with supercritical nitrogen or supercritical carbon dioxide to produce a thermoplastic foamed melt;
applying a gas counter pressure to the thermoplastic foamed melt;
expanding the thermoplastic foamed melt within a mold of the molding apparatus; and
cooling the expanded thermoplastic foamed melt.