Search

EP-4735505-A1 - BIODEGRADABLE POLYMER MATERIALS

EP4735505A1EP 4735505 A1EP4735505 A1EP 4735505A1EP-4735505-A1

Abstract

Various bio-based biodegradable materials, films, packaging materials, and methods of manufacture are provided herein. For example, such components may include polyvinyl alcohol (PVA) based materials that include lactic acid (LA) such as in the form of polylactic acid (PLA). In this regard, the synthesis of various PVA based copolymer on which PLA oligomers are grafted as a result of synthesis from LA. The result is a PVA-g-PLA copolymer, which is distinct from PVA and PLA blends.

Inventors

  • MASEK, ANNA
  • TUTEK, KAROL
  • KOSMALSKA-OLA SKA, Anna
  • LATOS-BRÓZIO, Malgorzata

Assignees

  • H.J. Heinz Company Brands LLC

Dates

Publication Date
20260506
Application Date
20240628

Claims (20)

  1. 1. A composition comprising: poly (vinyl alcohol) (PVA) backbone; and lactic acid (LA) grafted onto the PVA backbone.
  2. 2. The composition of claim 1 wherein the PVA is provided in a ratio to the LA (PVA:LA) in a range of about 1 : 1 to about 1 :4
  3. 3. The composition of claim 1 further comprising a filler.
  4. 4. The composition of claim 3 wherein the filler is selected from the group consisting of alkyl ketene dimers, tomato skin material, and combinations thereof.
  5. 5. The composition of claim 1 wherein the material is crosslinked.
  6. 6. The composition of claim 1 wherein the material is biodegradable.
  7. 7. The composition of claim 1 wherein the material is in the form of pellets used to form a polymeric film.
  8. 8. The composition of claim 1 wherein the material is in the form of a polymeric film.
  9. 9. A method for preparing a biodegradable packaging material, the method comprising the steps of: providing a poly (vinyl alcohol) (PVA) material; providing a lactic acid (LA) containing material; reacting the PVA material with the LA containing material in the presence of a catalyst to synthesize a PVA backbone with poly lactic acid (PLA) grafted onto the PVA backbone to form PVA-g-PLA.
  10. 10. The method of claim 9 wherein a ratio of the PVA material to the LA containing material is about 1 : 1 to 1 :4.
  11. 11. The method of claim 9 wherein the catalyst is provided in an amount of about 1 to about 1.5 wt.%
  12. 12. The method of claim 9 wherein the catalyst includes at least one of Sn(Oct)2, SnCk, ZnCk, and combinations thereof.
  13. 13. The method of claim 9 wherein the reaction is carried out over a time period of about 5 to about 7 hours.
  14. 14. The method of claim 9 wherein the reaction is carried out at a temperature of about 80°C to about 100°C.
  15. 15. The method of claim 9 further comprising the step of adding at least one of alkyl ketene dimers, fillers, coatings, stabilizers, polyhydroxyalkanoates, polycaprolactone, other biopolymers and combinations thereof.
  16. 16. The method of claim 9 further comprising the step of adding a cross-linking agent.
  17. 17. The method of claim 16 wherein the cross-linking agent includes at least one of citric acid, succinic acid, and combinations thereof.
  18. 18. The method of claim 9 further comprising the step of cross-linking the PVA-g- PLA using at least one of citric acid, succinic acid, UV radiation, and combinations thereof.
  19. 19. The method of claim 9 further comprising the step of forming the PVA-g-PLA into a film.
  20. 20. The method of claim 19 further comprising the step of combining the film with a second film.

Description

BIODEGRADABLE POLYMER MATERIALS FIELD [0001] The present application is directed to bio-based biodegradable polymer materials such as biodegradable packaging for comestibles and methods of manufacture. BACKGROUND [0002] Packaging materials are used to contain and protect a variety of items during storage and transport. A variety of materials such as cardboard, plastics, metal, and glass have historically been used for packaging. However, many packaging materials are deposited in a landfill after use. Non-renewable resources such as petroleum have been used to produce conventional non-biodegradable plastics. Though plastic-based packaging may be desirable due to their low cost, packaging materials containing such plastics can persist for a considerable period of time in the environment after disposal. [0003] There has been increasing demand that renewable resources and/or materials that more readily degrade in the environment be used to produce packaging materials. For instance, polylactic acid (PLA) is a bio-based biodegradable polymer formed from lactic acid (LA) that can be used for packaging. However, PLA is oftentimes brittle with high glass transition temperatures and high melting points. In other words, PLA, while being bio-based and biodegradable, may not be suitable for some packaging as it may not provide the necessary physical properties, chemical properties, and the like. [0004] For example, PLA may not be suitable for packaging for comestibles due to water content, pH, shelf life, or other attributes of the comestible or requirements of the packaging. However, because PLA is a renewable material that can be biodegradable, it may be desirable to incorporate the material with other components to form packaging for comestibles. In this regard, it may be desirable to provide for biobased biodegradable materials containing PLA that can be used as packaging for condiments, such as ketchup. [0005] Poly (vinyl alcohol) (PVA) is a synthetic polymer material that has many uses, such as in medical and pharmaceutical applications due to its biocompatibility. However, PVA fdms may also have disadvantages such as brittleness, low fracture elongation, poor water resistance, and processability. [0006] PVA and PLA blends have also been utilized to try to improve upon the performance of the materials. However, the blended form of these materials may still not provide suitable performance and function, such as for comestible packaging, depending on the usage. SUMMARY [0007] Various bio-based biodegradable materials, fdms, packaging materials, and methods of manufacture are provided herein. For example, such components may include polyvinyl alcohol (PVA) based materials that include lactic acid (LA) such as in the form of polylactic acid (PLA). In this regard, the synthesis of various PVA-based copolymer on which PLA oligomers are grafted as a result of synthesis from LA. The result is a PVA-g-PLA copolymer, which is distinct from PVA and PLA blends. [0008] The amounts of the components and reaction materials may be modified to provide desired performance in the resulting material and packaging. Similarly, the reaction and process parameters may also be modified to achieve desired performance and functionality. [0009] For example, the ratio of polyvinyl alcohol to lactic acid (PVA:LA ratio), the amount of catalyst and the total amount of water used as a solvent, the synthesis time and temperature may be modified separately or in combination, as needed. For example, a ratio of the amount to PVA to PLA is in a range of about 1 : 1 to about 1 :4. The synthesis time may also be varied to achieve the desired function, such as having a time of about 5 hours to about 7 hours. [0010] The copolymer may also be crosslinked. For example, crosslinking may be accomplishing using crosslinking agents such as citric acid, succinic acid, and the like. Additionally, higher temperatures, UV radiation, and the like may be used to help crosslink the copolymer as desired. [0011] The material may also be combined with other materials to form the film. Similarly, the material may be formed into a polymer film and then joined with other films, coated, and the like to achieve desired properties. [0012] The resulting material is a bio-based copolymer that has desirable transparent film properties along with high flexibility and high cohesive strength. The obtained material is easily sealable into a sachet by welding under simple laboratory conditions. [0013] These and other aspects may be understood more readily from the following description. BRIEF DESCRIPTION OF THE DRAWINGS [0014] FIG. 1 is a Differential Scanning Calorimetry (DSC) plot for Copolymer 12 before drying. [0015] FIG. 2 is a DSC plot for Copolymer 12 after drying at 80°C for 100 min. [0016] FIG. 3 is a DSC plot for Copolymer 13 before drying. [0017] FIG. 4 is a DSC plot for Copolymer 13 after drying at 80°C for 100 min. [0018] FIG. 5 is a DSC plot for Copolymer 14 after dr