Resilient foams and uses thereof

Patent metadata

Field	Value
Publication number	US-10227478-B2
Application number	US-201514734684-A
Country	US
Kind code	B2
Filing date	Jun 9, 2015
Priority date	Jul 24, 2014
Publication date	Mar 12, 2019
Grant date	Mar 12, 2019

Abstract

Disclosed is a resilient foam and methods of making the foam. The resilient foam includes a derivatized polyanionic polysaccharide and has an open-cell structure. When the resilient foam is contacted with water, the foam forms a thixotropic hydrogel.

First claim

The invention claimed is:

1. A resilient foam comprising:
(a) a derivatized polyanionic polysaccharide; and
(b) an open-cell structure, wherein
(i) the resilient foam, when contacted with water, is capable of forming a thixotropic hydrogel, and
(ii) the derivatized polyanionic polysaccharide has a degree of substitution of less than 0.6 derivatives per monomer unit.

2. The resilient foam of claim 1 , wherein the derivatized polyanionic polysaccharide is dissolvable in water.

3. The resilient foam of claim 1 , wherein the derivatized pdyamomc polysaccharide is carboxymethyl cellulose, cellulose ethyl sulfonate, carboxymethyl amylose, chondroitin-6-sulfate, chondroitin-4-sulfate, demiatan sulfate, alginate, heparin, or heparin sulfate, or any combination thereof.

4. The resilient foam of claim 3 , wherein the derivatized polyanionic polysaccharide is carboxymethyl cellulose.

5. The resilient foam of claim 4 , wherein the carboxymethyl cellulose has a non-uniform distribution of carboxymethvl groups.

6. The resilient foam of claim 4 , wherein the carboxymethyl cellulose has a consistent weight per unit length of polymer.

7. The resilient foam of claim 4 , wherein the carboxymethyl cellulose compound has a molecular weight of 50 to 400 kilodaltons.

8. The resilient foam of claim 4 , wherein the carboxymethyl cellulose is derived from cotton or cotton linters.

9. The resilient foam of claim 1 , wherein the derivatized polyanionic polysaccharide is cellulose ethyl sulfonate.

10. The resilient foam of claim 1 , further comprising water, wherein a weight ratio of the water to the derivatized polyanionic polysaccharide ranges from about 0.04 to about 0.6.

11. The resilient foam of claim 1 , further comprising water, wherein an amount of the water ranges from 20 to about 60 wt. % based on the total weight of the resilient foam.

12. The resilient foam of claim 1 . Wherein the resilient foam comprises 40 wt. % or more of the derivatized polyanionic polysaccharide.

13. The resilient foam of claim 1 , wherein the resilient foam is obtained from a hydrogel comprising the derivatized polyanionic polysaccharide, wherein the hydrogel has a yield stress of 200 Pa or more.

14. The resilient foam of elhim 13 , wherein the hydrogel comprises the derivatized polyanionic polysaccharide in an amount of about 3 to 15 wt. % of the hydrogel.

15. The resilient foam of claim 1 , wherein the resilient foam is flexible.

16. The resilient foam of claim 1 , wherein the resilient foam is capable of absorbing 60 wt. % of less of water and remain resilient.

17. The resilient foam of claim 1 , wherein the resilient foam is a nonliquid, non-flowable foam.

18. The resilient foam of claim 1 , wherein the derivatized polyanionic polysaccharide 1% or less of cross-linked polyanionic polysaccharide.

19. The resilient foam of claim 1 , wherein the derivatized polyanionic polysaccharide and/or resilient foam has not been subjected to cross-linking conditions.

20. The resilient foam of claim 1 , wherein the resilient foam is non-deliquescent when exposed to water vapor.

21. The resilient foam of claim 1 , the degree of substitution is between 0.2 to 0.55 derivatives per monomer unit.

22. The resilient foam of claim 21 , the degree of substitution is between 0.3 to 0.45 derivatives per monomer unit.

23. The resilient foam of claim 1 , wherein the resilient foam is hygroscopic and the resilient foam is capable of retaining resiliency after absorbing water in vapor form.

Assignees

• Arthrocare Corp
• Smith & Nephew Inc

Inventors

• Delli-Santi George T
• Betre Helawe

Classifications

• C08J2207/10

  Medical applications, e.g. biocompatible scaffolds · CPC title

• A61L15/28

  Polysaccharides or their derivatives {(A61L15/225 takes precedence)} · CPC title

• A61L31/146

  Porous materials, e.g. foams or sponges · CPC title

• A61L2400/16

  Materials with shape-memory or superelastic properties · CPC title

• C08J9/28 Primary

  by elimination of a liquid phase from a macromolecular composition or article, e.g. drying of coagulum · CPC title