Search

US-12623420-B2 - Process for making recyclable copolyesters articles with living hinges

US12623420B2US 12623420 B2US12623420 B2US 12623420B2US-12623420-B2

Abstract

A process for making a fully recyclable packaging article comprising (1) a reclosable lid with a living hinge which comprises a copolyester composition that is recyclable in a PET stream, (2) a container which comprises a copolyester composition that is recyclable in a PET stream; and affixed thereto is (3) a crystallizable shrinkable film or label which comprises a copolyester composition that is recyclable in a PET stream.

Inventors

  • Marc Alan Strand
  • Matthew Clement Storey
  • Aaron David Grills
  • Mark Allen Peters

Assignees

  • EASTMAN CHEMICAL COMPANY

Dates

Publication Date
20260512
Application Date
20221117

Claims (20)

  1. 1 . A process for producing three-component recyclable article comprising A) producing component A—a reclosable lid with a living hinge as a single component by injection molding at least one polyester using a mold with one or more injection points wherein the average polyester flow length divided by the average thickness of the lid is below 200; wherein at least one polyester comprises: (a) a dicarboxylic acid component comprising: (i) 88 to 100 mole % of terephthalic acid residues; (ii) 0 to 12 mole % of aromatic and/or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) a glycol component comprising: (i) 88 to 100 mole % of ethylene glycol residues; and (ii) 0 to 12 mole % of 1,4-cyclohexanedimethanol residues; wherein the total mole % of the acid residues is 100 mole %, and the total mole % of the glycol residues is 100 mole %; wherein the inherent viscosity (IhV) of said polyester ranges from 0.60 to 1.1 dL/g as determined in 60/40 (wt/wt) phenol/tetrachloroethane at a concentration of 0.25 g/50 ml at 25° C.; and wherein the melting point temperature (T m ) of said polyester ranges from 225 to 255° C. as determined by ASTM D3418 at a scan rate of 10° C./min; B) producing component B—a container by injection stretch blow molding at least one polyester; wherein at least one polyester comprises: (a) a dicarboxylic acid component comprising: (i) 88 to 100 mole % of terephthalic acid residues; (ii) 0 to 12 mole % of aromatic and/or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) a glycol component comprising: (i) 88 to 100 mole % of ethylene glycol residues; and (ii) 0 to 12 mole % of 1,4-cyclohexanedimethanol residues; and (c) optionally at least one branching agent in the amount ranging from 0.1 to 1.0 mole % based on the total moles of glycol residues if said branching agent has hydroxyl substituents and otherwise based on the total moles of acid residues; wherein the total mole % of the acid residues is 100 mole %, and the total mole % of the glycol residues is 100 mole %; wherein the inherent viscosity (IhV) of said polyester ranges from 0.60 to 1.1 dL/g as determined in 60/40 (wt/wt) phenol/tetrachloroethane at a concentration of 0.25 g/50 ml al 25° C.; and wherein the melting point temperature (T m ) of said polyester ranges from 225 to 255° C. as determined by ASTM D3418 at a scan rate of 10° C./min and C) producing component C—a heat shrinkable film or label from at least one crystallizable resin which comprises a polyester composition comprising: at least one polyester which comprises: (a) a dicarboxylic acid component comprising: (i) about 70 to about 100 mole % of terephthalic acid residues; (ii) about 0 to about 30 mole % of aromatic and/or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) a diol component comprising: about 75 mole % or greater of ethylene glycol residues and about 25 mole % or less of other glycols comprising one or more of: (i) about 0.1 to less than about 24 mole % of neopentyl glycol residues; (ii) 0 to less than about 24 mole % of 1,4-cyclohexanedimethanol residues; (iii) about 1 to less than about 10 mole % of total diethylene glycol residues in the final polyester composition; wherein the total mole % of the dicarboxylic acid component is 100 mole %, and wherein the total mole % of the diol component is 100 mole %; or C′) producing component C′—a heat shrinkable film or label from at least one crystallizable resin which comprises a blend of polyester compositions comprising: (1) 5-80% of at least one crystallizable polyester which comprises: (a) a dicarboxylic acid component comprising: (i) about 70 to about 100 mole % of terephthalic acid residues; (ii) about 0 to about 30 mole % of aromatic and/or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and a diol component chosen from either (b) or (b′), wherein (b) is a diol component comprising: about 75 mole % or greater of ethylene glycol residues and about 25 mole % or less of other glycols comprising one or more of: (i) about 0 to less than about 25 mole % of neopentyl glycol residues; (ii) about 0 to less than about 25 mole % of 1,4-cyclohexanedimethanol residues; (iii) about 0 to less than about 10 mole % of total diethylene glycol residues in the final polyester composition; wherein the total mole % of the dicarboxylic acid component is 100 mole %, and wherein the total mole % of the diol component is 100 mole %; or wherein (b′) is a diol component comprising: about 75 mole % or greater of ethylene glycol residues and about 25 mole % or less of other glycols comprising one or more of: (i) about 0.1 to less than about 24 mole % of neopentyl glycol residues; (ii) about 0.1 to less than about 24 mole % of 1,4-cyclohexanedimethanol residues; (iii) about 1 to less than about 10 mole % of total diethylene glycol residues in the final polyester composition; wherein the total mole % of the dicarboxylic acid component is 100 mole %, and wherein the total mole % of the diol component is 100 mole %; and (2) 20-95% of at least one amorphous polyester which comprises: (a) a dicarboxylic acid component comprising: (i) about 70 to about 100 mole % of terephthalic acid residues; (ii) about 0 to about 30 mole % of aromatic and/or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) a diol component comprising: about 60 mole % or greater of ethylene glycol residues and about 40 mole % or less of other glycols comprising one or more of: (i) about 0 to less than about 40 mole % of neopentyl glycol residues; (ii) about 0 to less than about 40 mole % of 1,4-cyclohexanedimethanol residues; (iii) about 0 to less than about 15 mole % of total diethylene glycol residues in the final polyester composition, whether or not formed in situ; wherein the total mole % of the dicarboxylic acid component is 100 mole %, and wherein the total mole % of the diol component is 100 mole %; and wherein (1) and (2) are different.
  2. 2 . The process of claim 1 , further comprising attaching component A—the lid to component B—the container and affixing component C—the film or label onto component B—the container or onto a portion of component B—the container and a portion of component A—the attached lid.
  3. 3 . The process of claim 1 , wherein in A) the average polyester flow length divided by the average thickness of component A—the lid is below 175; or wherein in A) the average polyester flow length divided by the average thickness of component A—the lid is below 150, or wherein in A) the average polyester flow length divided by the average thickness of component A—the lid is below 100.
  4. 4 . The process of claim 1 , wherein in A) the mold has one injection point; or wherein in A) the mold has two injection points.
  5. 5 . The process of claim 1 , wherein all three components-component A—the lid, component B—the container and component C—the film are transparent and/or clear and recyclable in a PET recycle stream.
  6. 6 . The process of claim 1 , wherein component A—the lid produced in A) has an average thickness of from 0.5-2 mm.
  7. 7 . The process of claim 1 , wherein component A—the lid produced in A) has a living hinge with an average thickness of from 0.1-1 mm.
  8. 8 . The process of claim 1 , wherein the polyester of component A has 0 to mole % of 1,4-cyclohexanedimethanol residues.
  9. 9 . The process of claim 1 , wherein the polyester of component A has 0.1 to 10 mole % of 1,4-cyclohexanedimethanol residues.
  10. 10 . The process of claim 1 , wherein the living hinge of component A has a strength value of at least 500 cycles; or has a strength value of at least 700 cycles; or has a strength value of at least 600 cycles; or has a strength value of at least 1000 cycles.
  11. 11 . The process of claim 1 , wherein the inherent viscosity (IhV) of polyester in component A or component B ranges from 0.60 to 0.8 dL/g.
  12. 12 . The process of claim 1 , further comprising at least one polyester with recycle content in component A and/or component B and/or component C.
  13. 13 . The process of claim 1 , wherein the inherent viscosity of the polyester for component C—the film or label is from 0.68 to 0.75 dL/g as determined in 60/40 (wt/wt) phenol/tetrachloroethane at a concentration of 0.5 g/dl at 25° C., and wherein the polyester has a Tg of from 72° C. to 77° C. as determined using a TA DSC 2920 from Thermal Analyst Instrument at a scan rate of 20° C./min.
  14. 14 . The process of claim 1 , wherein for component C—the film or label the sum of the diol content of one or more diol monomer components capable of forming an amorphous component in the final polyester is from 10 to 20 mole % wherein the total diol content is 100 mole %; or wherein the sum of the diol content of one or more diol monomer components capable of forming an amorphous component in the final polyester is from 15 to 20 mole % wherein the total diol content is 100 mole %.
  15. 15 . The process of claim 1 , wherein for component C—the film or label the 1,4-cyclohexanedimethanol residues are present in the amount of 0 to 5 mole %, diethylene glycol residues are present in the amount of 5 mole % or less, neopentyl glycol residues in the amount of 10 to 15 mole %, and ethylene glycol residues are present in the amount of greater than 75 mole %.
  16. 16 . The process of claim 1 , wherein for component C—the film or label said film is stretched in at least one direction; or wherein said film is oriented in one or more directions; or wherein said film is stretched and oriented in at least one direction; or wherein said film is annealed or wherein said film is annealed at a temperature from about 75° C. to about 110° C.
  17. 17 . The process of claim 1 , wherein for component C—the film or label said film is stretched in at least one direction and the stretched film has a strain induced crystalline melting point of 200° C. or greater.
  18. 18 . The process of claim 1 , wherein for component C—the film or label said film has shrinkage in the main shrinkage direction of from 60% or greater when immersed in water at 85° C. for 10 seconds.
  19. 19 . The process of claim 1 , wherein for component C—the film or label said film has a shrink force of 5 MPa or greater.
  20. 20 . The process of claim 1 , wherein for component C—the film or label said film has a shrinkage in the main shrinkage direction in the amount of 50 to 90% and shrinkage in the direction orthogonal to the main shrinkage direction of 10% or less when immersed in water at 95° C. for 10 seconds.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S) This application is a national stage filing under 35 USC § 371 of International Application Number PCT/US2022/050197, filed on Nov. 17, 2022 which claims the benefit of the filing date to U.S. Provisional Application No. 63/264,413, filed on Nov. 22, 2021, the entire disclosures of which are incorporated by reference herein. FIELD OF THE INVENTION The present disclosure relates to a process for making a fully recyclable packaging article comprising (1) a reclosable lid with a living hinge which comprises a RIC1 compatible copolyester composition, (2) a container which comprises a RIC1 compatible copolyester composition; and affixed thereto is (3) a crystallizable shrinkable film or label which comprises a copolyester composition recyclable in a PET stream. BACKGROUND OF THE INVENTION There is a commercial need for fully recyclable containers and packaging articles in which each component of the article; the reclosable lid with a living hinge, the container and the film or label is recyclable in a PET stream. To be considered recyclable, the articles must be transformable at the end of life back into usable polymeric material. Currently, poly(ethylene terephthalate) (PET) is the largest volume thermoplastic with an existing and well-established mechanical recycling stream. Recycling of post-consumer PET is a complex process that involves separating opaque, colored and transparent components from each other as well as from containers made from different materials (e.g. polyethylene, polypropylene, PVC, etc.). Proper separation is critical as each of these materials can contaminate the PET stream and reduce the quality of the final sorted product. After separation, the clear PET bottles are ground into flake, cleaned, and dried at temperatures between 140° C. and 180° C. The flake may be used directly (for example in strapping and fiber extrusion) or further processed into pellets for film, sheet or bottle applications. For some applications the pellets may be further crystallized and solid-state polymerized at temperatures between 200° C. and 220° C. prior to use. Because of the well-established nature of PET recycling processes, it is desirable for copolyester-based molded articles and containers to be compatible with the existing PET recycle streams. Historically, lids with living hinges were produced from olefins such as polypropylene and polyethylene which are not compatible with PET recycle streams. The present disclosure addresses a long felt commercial need for durable molded articles with living hinges produced from copolyester thermoplastic materials that are transparent, as well as clear, tough, flexible and recyclable in a PET stream. BRIEF SUMMARY OF THE INVENTION One aspect of the present disclosure is a process for producing three-component recyclable article comprising A) producing component A—a reclosable lid with a living hinge as a single component by injection molding at least one polyester using a mold with one or more injection points wherein the average polyester flow length divided by the average thickness of the lid is below 200; wherein at least one polyester comprises: (a) a dicarboxylic acid component comprising: (i) 88 to 100 mole % of terephthalic acid residues; (ii) 0 to 12 mole % of aromatic and/or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) a glycol component comprising: (i) 88 to 100 mole % of ethylene glycol residues; and (ii) 0 to 12 mole % of 1,4-cyclohexanedimethanol residues; wherein the total mole % of the acid residues is 100 mole %, and the total mole % of the glycol residues is 100 mole %; wherein the inherent viscosity (IhV) of said polyester ranges from 0.60 to 1.1 dL/g as determined in 60/40 (wt/wt) phenol/tetrachloroethane at a concentration of 0.25 g/50 ml at 25° C.; and wherein the melting point temperature (Tm) of said polyester ranges from 225 to 255° C. as determined by ASTM D3418 at a scan rate of 10° C./min; B) producing component B—a container by injection stretch blow molding at least one polyester; wherein at least one polyester comprises: (a) a dicarboxylic acid component comprising: (i) 88 to 100 mole % of terephthalic acid residues; (ii) 0 to 12 mole % of aromatic and/or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) a glycol component comprising: (i) 88 to 100 mole % of ethylene glycol residues; and (ii) 0 to 12 mole % of 1,4-cyclohexanedimethanol residues; and (c) optionally at least one branching agent in the amount ranging from 0.1 to 1.0 mole % based on the total moles of glycol residues if said branching agent has hydroxyl substituents and otherwise based on the total moles of acid residues; wherein the total mole % of the acid residues is 100 mole %, and the total mole % of the glycol residues is 100 mole %; wherein the inherent viscosity (IhV) of said polyester ranges from 0.60 to 1.1 dL/g as determined in 60/40 (wt/wt) phenol/tetrachloroethane