Outer layer having entanglement of hydrophobic polymer host and hydrophilic polymer guest
An outer layer having an entanglement comprising an intermingling of cloaked hydrophilic guest and a hydrophobic polymer host, wherein molecules of the guest have been crosslinked with each other. Under certain circumstances, using complexes of the guest may be desirable or even necessary. The intermingling of the guest and host includes a physical tangling, whether it also comprises crosslinking by primary bonding (e.g., chemical/covalent bonding) there-between. Also a method of producing an outer layer having such an entanglement, including the steps of: temporarily cloaking at least a portion of the hydrophilic groups of the guest; intermingling at least a portion of the cloaked groups with a porous polymeric structure by diffusing the guest with cloaked groups into at least a portion of the structure's pores; within the pores, crosslinking at least a portion of the molecules of the guest with the guest; and removing the cloaking. Cloaking may be performed by silylation or acylation. Intermingling may be performed by producing a mixture of guest and host (whether in solution, powdered, granular, etc., form); next, a crosslinking of the guest with itself is performed; then, the mixture is molded into the outer layer.
1. A method of producing an outer layer having an entanglement comprising a hydrophobic porous polymeric host structure and a hydrophilic guest having hydrophilic groups, wherein said guest comprises hyaluronic acid, the method comprising the steps of:
temporarily cloaking at least a portion of the hydrophilic groups of the hydrophilic guest to yield a cloaked hydrophilic guest;
intermingling at least a portion of said cloaked hydrophilic guest with the hydrophobic porous polymeric host structure by diffusing the cloaked hydrophilic guest into a plurality of pores of the porous polymeric host structure, wherein the hydrophobic porous polymeric host structure comprises a hydrophobic polymer host comprising a water-insoluble hydrocarbon-based polymer;
within said pores, crosslinking at least a portion of molecules of the hydrophilic guest with the guest; and
removing the temporary cloaking to produce a hydrophilic outer surface of the outer layer.
2. The method of claim 1 wherein: said intermingling is performed using complexes of the hydrophilic guest comprising an QN + group, where QN + represents a long-chain paraffin ammonium cation; said cloaking said hydrophilic groups of said complexes comprises performing a silylation using a silylating agent; and said step of removing further comprises performing a hydrolysis reaction.
3. The method of claim 1 wherein: the hydrophobic porous polymeric host structure is a molded form comprising ultra high molecular weight polyethylene; said intermingling is performed using complexes of the hydrophilic guest comprising an QN + group, where QN + represents a cation selected from the group consisting of alkyltrimethylammonium chloride, alkylamine hydrochloride, alkylpyridinium chloride, alkyldimethylbenzyl ammonium chloride, alkyltrimethylammonium bromide, alkylamine hydrobromide, alkylpyridinium bromide, and alkyldimethylbenzyl ammonium bromide; and further comprising the step of dissociating said QN + groups from said guest complexes in a salt solution.
4. The method of claim 1 wherein: said cloaking said hydrophilic groups comprises performing a silylation using a silylating agent; and said crosslinking further comprises exposing said cloaked guest within said pores to a crosslinker.
5. The method of claim 4 wherein: said intermingling is performed using complexes of the hydrophilic guest; and said step of removing further comprises performing a hydrolysis reaction; and further comprising the step of returning the hydrophilic guest complexes to a pre-complex state by dissociation of a group therefrom.
6. A method of producing an outer layer having an entanglement comprising a hydrophobic polymer host and a hydrophilic guest having hydrophilic groups, wherein said guest comprises hyaluronic acid, comprising the steps of:
temporarily cloaking at least a portion of the hydrophilic groups of the hydrophilic guest, by performing acylation thereon, thereby yielding an acylated hydrophilic guest;
entangling the hydrophilic guest and the hydrophobic polymer host by producing a mixture comprising said acylated hydrophilic guest and the hydrophobic polymer host, said hydrophobic polymer host comprising a water-insoluble hydrocarbon-based polymer, and crosslinking at least a portion of molecules of the hydrophilic guest with the guest; and
molding said mixture into the outer layer.
7. The method of claim 6 further comprising drying said acylated hydrophilic guest complexes, and wherein said mixture is in powdered form, and further comprising the step of removing said cloaking to produce a hydrophilic outer surface of the outer layer.
8. The method of claim 7 wherein: said entangling is performed using complexes of the hydrophilic guest comprising an QN + group, where QN + represents a long-chain paraffin ammonium cation; said performing acylation further comprises using an acid chloride; and said removing further comprises performing a hydrolysis reaction.
9. The method of claim 6 wherein: the hydrophilic guest is hyaluronic acid; said entangling is performed using complexes of the hydrophilic guest represented according to the expression HA − -QN + , where HA represents hyaluronic acid and QN + represents a cation; said cloaked hydrophilic groups of the guest complexes comprise acylated functional groups; and at least a portion of said crosslinking to occur during said step of molding said mixture; and further comprising, prior to said step of molding, the step of removing said cloaking to produce a hydrophilic outer surface of the outer layer.