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US-12624308-B2 - Biodegradable delivery particles

US12624308B2US 12624308 B2US12624308 B2US 12624308B2US-12624308-B2

Abstract

A biodegradable delivery particle having a benefit agent containing core and a shell.

Inventors

  • Susana FERNÁNDEZ PRIETO
  • Valerie Francine Hans Eykens
  • Rita Del Pezzo
  • Johan Smets
  • Linsheng Feng
  • Fadi Selim Chakar
  • Travis Ian Bardsley
  • Robert Stanley Bobnock

Assignees

  • ENCAPSYS, LLC

Dates

Publication Date
20260512
Application Date
20211118

Claims (20)

  1. 1 . A delivery particle comprising a core and a wall encapsulating said core, wherein: the core comprises a benefit agent and a partitioning modifier; the wall is formed by a radical polymerization reaction between: a) a water soluble hydroxyl containing linear carbon-chain polymer comprising 1,2-diol and/or 1,3-diol functionality; b) a multifunctional (meth)acrylate monomer and/or oligomer; c) optionally, a mono- and/or di-functional monomer and/or oligomer; d) at least one water soluble thermal free radical initiator; e) at least one oil soluble thermal free radical initiator; wherein at least one of the water-soluble initiators is a persulfate and the water soluble hydroxyl containing linear carbon-chain polymer forms carbon/carbon and/or oxygen/carbon bonds with the multifunctional (meth)acrylate monomer and/or oligomer.
  2. 2 . The delivery particle of claim 1 , wherein the benefit agent is a fragrance.
  3. 3 . The delivery particle of claim 1 , wherein the partitioning modifier is selected from the group consisting of isopropyl myristate, vegetable oil, modified vegetable oil, mono-, di-, and tri-esters of C4-C24 fatty acids, dodecanophenone, lauryl laurate, methyl behenate, methyl laurate, methyl palmitate, methyl stearate, and mixtures thereof.
  4. 4 . The delivery particle of claim 1 , wherein the water soluble hydroxyl containing polymer has a degree of hydrolysis from about 55% to about 99%.
  5. 5 . The delivery particle of claim 1 , wherein the water soluble hydroxyl containing linear carbon-chain polymer is partially acetylated.
  6. 6 . The delivery particle of claim 1 , wherein the wall further comprises a polysaccharide.
  7. 7 . The delivery particle of claim 6 , wherein the polysaccharide has at least one amine moiety.
  8. 8 . The delivery particle of claim 6 , wherein the polysaccharide is selected from the group consisting of pectin, carrageenan, cellulose, chitosan, chitin, xanthan gum, tara gum, konjac gum, alginate, hyaluronic acid, amylase, lignin, diutan gum, and mixtures thereof.
  9. 9 . The delivery particle of claim 1 , wherein the water soluble hydroxyl containing linear carbon-chain polymer is at least 20 weight percentage of the total wall.
  10. 10 . The delivery particle of claim 1 , wherein the polysaccharide is at least 2% weight percentage of the total wall.
  11. 11 . The delivery particle of claim 1 , wherein the water soluble hydroxyl containing linear carbon-chain polymer and/or the polysaccharide has a molecular weight from about 30 kDa to about 500 kDa.
  12. 12 . The delivery particle of claim 1 , wherein the water soluble hydroxyl containing linear carbon-chain polymer and/or polysaccharide has a biodegradability above 30% CO 2 in 60 days following OECD 301B test.
  13. 13 . The delivery particle of claim 1 , wherein the multifunctional (meth)acrylate monomer and/or oligomer is selected from group consisting of tri-functional (meth)acrylate, tetra-functional (meth)acrylate, penta-functional (meth)acrylate, hexa-functional (meth)acrylate, hepta-functional (meth)acrylate, and mixtures thereof.
  14. 14 . The delivery particle of claim 1 , wherein the multifunctional (meth)acrylate monomers and/or oligomer comprises a hexafunctional aromatic urethane acrylate.
  15. 15 . The delivery particle of claim 1 , wherein the multifunctional (meth)acrylate monomer and/or oligomer comprises a multifunctional aliphatic urethane acrylate.
  16. 16 . The delivery particle of claim 1 , wherein the multifunctional (meth)acrylate monomer and/or oligomer is at least 5%.
  17. 17 . The delivery particle of claim 1 , wherein the mono- and/or di-functional monomer and/or oligomer are independently selected from the group consisting of: wherein R1, R2, RS, R6, R7, R8, R9 and RIO are independently selected from the group consisting of a hydrogen (*—H) and a methyl group (*—CH3); a, b, c and dare integers independently selected from 1 to 10, R3 and R4 are independently selected from the group consisting of h and i are integers independently selected from 0 to 10; R 11 is selected from the group consisting of hydroxyl (*—OH), hydrogen (*—H), and methyl group (*—CH 3 ).
  18. 18 . The delivery particle of claim 1 , wherein the water soluble thermal free radical initiator is selected from the group consisting of ammonium persulfate, potassium persulfate, sodium persulfate and mixtures thereof.
  19. 19 . The delivery particle of claim 1 , wherein the oil soluble thermal free radical initiator is an azo-based initiator.
  20. 20 . The delivery particle of claim 15 , wherein the azo-based initiator is selected from the group consisting of 2,2′-azobis(isobutylnitrile), 2,2′-azobis(2,4-dimethylpentanenitrile), 2,2′-azobis(2,4-dimethylvaleronitrile), 2,2′-azobis(2-methylpropanenitrile), 2,2′-azobis(2-methylbutyronitrile), 1,1′-azobis (cyclohexanecarbonitrile), 1,1′-azobis(cyanocyclohexane) and mixtures thereof.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is a national stage (§ 371) application of International Application PCT/US2021/059875 filed Nov. 18, 2021, which claims benefit of U.S. Provisional Application No. 63/116,134 filed Nov. 19, 2020. Encapsys, LLC (formerly known as the Encapsys division of Appleton Papers Inc.) and The Procter & Gamble Company executed a Joint Research Agreement on or about Nov. 28, 2005 and this invention was made as a result of activities undertaken within the scope of that Joint Research Agreement between the parties that was in effect on or before the date of this invention. FIELD OF THE INVENTION The invention relates to biodegradable delivery particles having a benefit agent containing core and a wall. BACKGROUND OF THE INVENTION Microencapsulation is a process where droplets of liquids, particles of solids or gasses are enclosed inside a solid shell and are generally in the micro-size range. The core material is then mechanically separated from the surrounding environment through a membrane (Jyothi et al., Journal of Microencapsulation, 2010, 27, 187-197). Microencapsulation technology is attracting attention from various fields of science and has a wide range of commercial applications for different industries. Overall, capsules are capable of one or more of (i) providing stability of a formulation or material via the mechanical separation of incompatible components, (ii) protecting the core material from the surrounding environment, (iii) masking or hiding an undesirable attribute of an active ingredient and (iv) controlling or triggering the release of the active ingredient to a specific time or location. All of these attributes can lead to an increase of the shelf-life of several products and a stabilization of the active ingredient in liquid formulations. Encapsulation can be found in areas such as pharmaceuticals, personal care, textiles, food, coatings and agriculture. In addition, the main challenge faced by microencapsulation technologies in real-world commercial applications is that a complete retention of the encapsulated active within the capsule is required throughout the whole supply chain, until a controlled or triggered release of the core material is applied (Thompson et al., Journal of Colloid and Interface Science, 2015, 447, 217-228). There are significantly limited microencapsulation technologies that are safe for both the environment and human health with a long-term retention and active protection capability that can fulfill the needs of the industry nowadays, especially when it comes to encapsulation of small molecules. Over the past several years, consumer goods manufacturers have used core-shell encapsulation techniques to preserve actives, such as benefit agents, in harsh environments and to release them at the desired time, which may be during or after use of the consumer goods. Among the several mechanisms that can be used for release of benefit agent, the one commonly relied upon is mechanical rupture of the capsule shell. Selection of mechanical rupture as the release mechanism constitutes another challenge to the manufacturer, as rupture must occur at specific desired times, even if the capsules are subject to mechanical stress prior to the desired release time. Industrial interest for encapsulation technology has led to the development of several polymeric capsules chemistries which attempt to meet the requirements of biodegradability, low shell permeability, high deposition, targeted mechanical properties and rupture profile. Increased environmental concerns have put the polymeric capsules under scrutiny, therefore manufacturers have started investigating sustainable solutions for the encapsulation of benefit agents. Biodegradable materials exist and are able to form delivery particles via coacervation, spray-drying or phase inversion precipitation. However, the delivery particles formed using these materials and techniques are highly porous and not suitable for aqueous compositions containing surfactant, since the benefit agent is prematurely released to the composition. Non-leaky and performing delivery particles in aqueous surfactant-based compositions exist, however due to its chemical nature and cross-linking, they are not biodegradable. Delivery particles are needed that are biodegradable, yet have high structural integrity so as to reduce leakage and resist damage from harsh environments. DETAILED DESCRIPTION OF THE INVENTION In accordance with embodiments, delivery particles with improved biodegradability comprising a core substantially enclosed in a polymer wall, the core comprising a benefit agent and a partitioning modifier, and the polymer wall obtained by the reaction of polymerizable monomers, such as (meth)acrylate monomers, with water soluble hydroxyl containing linear carbon-chain polymer comprising 1,2-diol and/or 1,3-diol functionality to initiate the polymerization of the wall. Examples of natural and syntheti