Methods and systems of graft polymerization on a functionalized substrate

Abstract

Graft polymerization is fulfilled on a functionalized substrate. The functionalized substrate is prepared from a disulfide bond-containing feedstock and has been prepared for polymerization through the introduction of one or more polyfunctional monomers containing a disulfide bond breaking material functional group.

Claims

1. A grafted substrate comprising: a substrate; a polyfunctional monomer; and a graft polymer grafted on the substrate via the polyfunctional monomer, wherein the polyfunctional monomer is chemically bonded to the substrate and the polymer, wherein the graft polymer is formed using a condensation polymerization reaction, and wherein the polyfunctional monomer is bonded to the substrate via a disulfide bond.

2. The grafted substrate of claim 1, wherein the polyfunctional monomer is bonded to the polymer via a sulfur-carbon bond.

3. The grafted substrate of claim 1, wherein the substrate includes cysteine or cysteine-containing material.

4. The grafted substrate of claim 1, wherein the polyfunctional monomer includes a functional group, the functional group includes at least one of an acid anhydride, an isothiocyanate, an acyl halide, an alcohol, an aldehyde, an alkene, an alkyne, an amine, a carboxylic acid, an ester and/or a thiol.

5. The grafted substrate of claim 1, wherein the polyfunctional monomer includes a functional group, the functional group includes at least one ring, the ring being adapted to be opened to form at least a second functional group.

6. The grafted substrate of claim 1, further comprising a polyester polymer, wherein the polyester polymer is bonded to the polyfunctional monomer via an ester bond.

7. A functionalized substrate and graft polymer combination comprising: a substrate; and a polyfunctional monomer, wherein the polyfunctional monomer including at least one first functional group and at least one second functional group, the first functional group including a first thiol group, and the second functional group including a second thiol group configured to react with a condensation polymerizable monomer, the first thiol group forming a disulfide bond with the substrate, wherein the graft polymer is formed using a condensation polymerization reaction.

8. The functionalized substrate and graft polymer combination of claim 7, wherein the polyfunctional group includes a third functional group, the third functional group includes at least one of an acid anhydride, an acyl halide, an isothiocyanate, an alcohol, an aldehyde, an alkene, an alkyne, an amine, a carboxylic acid, an ester and/or a thiol.

9. The functional substrate of claim 7, wherein the polyfunctional group includes a third functional group, the third functional group includes at least one ring, the ring being adapted to be opened to form at least a fourth functional group.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1a is an illustration of one embodiment of the functionalization of a disulfide bond-containing feedstock.

(2) FIG. 1b is an illustration of one embodiment of the process flow of the functionalization of a disulfide bond-containing feedstock.

(3) FIG. 2 is an illustration of one embodiment of the graft polymerization on a functionalized substrate, and its polymerization without the addition of M.sup.2 monomer(s).

(4) FIG. 3 is an illustration of one embodiment of the overview of a graft polymerization on a functionalized substrate through the introduction of an M.sup.2 monomer.

(5) FIG. 4 is an illustration of an embodiment of a graft polymerization on a functionalized substrate utilizing different monomers M.sup.2-1 and M.sup.2-2 for the polymerization.

(6) FIG. 5 is an illustration of one embodiment of the process flow of graft polymerization on a functionalized substrate.

DETAILED DESCRIPTION

(7) In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which are shown, by way of illustration, specific embodiments in which the inventive concepts may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the described systems and methods, and it is to be understood that the embodiments may be combined or used separately, or that other embodiments may be used, and that design, implementation, and procedural changes may be made without departing from the spirit and scope of the inventive concepts. The following detailed description provides examples.

(8) The terms feedstock and disulfide bond-containing feedstock may be used interchangeably and are defined as one or more material(s), or combinations thereof, comprising or containing proteins, peptides, or other disulfide bond-containing materials. Such feedstock may be waste stream materials, for example avian feathers, hair, or wool.

(9) The term functionalized substrate is defined as a disulfide bond-containing feedstock or components thereof that has been prepared for polymerization through the introduction of one or more polyfunctional monomers, one of the functional groups of which must be a thiol (SH) or other disulfide bond breaking group, to break the disulfide bonds between the cysteine residues crosslinking the feedstock and reform new disulfide bonds between the cysteine residues of the feedstock and the attacking thiol or other disulfide bond breaking group.

(10) The term graft polymerization is defined as a reaction or reactions occurring on a functionalized substrate wherein the polymerization occurs at the functionalization site(s). Note that this definition does not assume or require a particular sequence or timing of events, unless specifically stated.

(11) The term solids graft polymerization is defined as a graft polymerization performed without substantial use of water or solvent (whether aqueous or non-aqueous) as a dispersant or for any other purpose. Note that this definition does not preclude the evolution of water or other chemicals as byproducts of the polymerization reaction, and furthermore does not preclude the use of aqueous solutions for preparation of the proteins, peptides, and other disulfide bonded materials for this disclosed process and method.

(12) The term cysteine residue is defined as what is left of a cysteine molecule after the cysteine molecule is incorporated within a protein, peptide or other material containing disulfide bonds.

(13) The term functional group is defined as a group of atoms found within molecules that are involved in the chemical reactions characteristic of those molecules such as but not limited to acid anhydrides, acyl halides, alcohols, aldehydes, alkenes, alkynes, amines, carboxylic acids, esters and thiols.

(14) The term solvent(s) includes water, aqueous solvents and non-aqueous solvents.

(15) The letter M.sup.1 is representative of a polyfunctional monomer containing at least one disulfide bond breaking group and one or more additional functional groups A.sup.1, A.sup.2, A.sup.3, . . . and A.sup.n (n is an integer larger than one).

(16) The letter M.sup.2 is representative of a monomer wherein M.sup.2-1, M.sup.2-2, . . . and M.sup.2-n (n is an integer larger than one) refer to different monomers used in a polymerization process.

(17) The letter S is representative of a sulfur atom.

(18) The letters A.sup.1, A.sup.2, A.sup.3, and A.sup.n are representative of functional groups that may or may not be the same.

(19) The letter R is representative of a generic hydrocarbon or hydrocarbon chain that may be an alkyl, aromatic, linear, branched or any combination thereof.

(20) Note that in the following illustrations, superscripts do not denote the number of atoms involved (for example S.sup.1 or A.sup.1), but are simply used to differentiate between atoms or functional groups for purposes of clarity.

(21) FIG. 1a and FIG. 1b illustrate an overview and process flow of an exemplary functionalization of a disulfide bond-containing feedstock 100 wherein a polyfunctional monomer 115, 175 is added to the feedstock 105, 170 to break the disulfide bonds 110 between the cysteine residues crosslinking the feedstock 100 and reform new disulfide bonds 145 between one of the cysteine residues of the feedstock and the attacking thiol groups.

(22) In particular, FIG. 1a is an illustration of one embodiment of the functionalization of a disulfide bond-containing feedstock 100 (for example, a protein) through the introduction of a polyfunctional monomer, of which at least one functional group is a disulfide bond breaking group (such as a thiol group) 120, to break the disulfide bonds between the cysteine residues crosslinking the feedstock 100 and reform new disulfide bonds between one of the cysteine residues of the feedstock and the attacking thiol group 145. FIG. 1b is an illustration of one embodiment of the process flow of the functionalization of a disulfide bond-containing feedstock through the introduction of a polyfunctional monomer, of which at least one functional group must be thiol or other disulfide bond breaking material, to break the disulfide bonds between the cysteine residues crosslinking the protein and reform new disulfide bonds between one of the cysteine residues of the feedstock and the attacking thiol or other disulfide bond breaking group.

(23) The disulfide bonds 110 are the bonds between two cysteine residues that are part of and sometimes crosslink proteins, peptides or other materials 105 containing the disulfide bonds 110. As shown in step 170 and 175, at least one polyfunctional monomer M.sup.1 115 including at least one disulfide breaking group 120 (e.g. thiol group) and one A.sup.1 functional group 125 and optionally one A.sup.2 functional group 130 or two functional groups A.sup.2 130 and A.sup.3 135 respectively may be added.

(24) In accordance with FIG. 1b, the feedstock has been functionalized at step 185 and is stable and the functionalized substrate may be shipped at step 190 to a customer for further processing. Functional groups A.sup.1, A.sup.2, and A.sup.3 may be any functional group of choice dependent upon the target polymer. Furthermore, multiple and different polyfunctional monomers M.sup.1 may be added as required dependent upon the polymer to be produced. At step 180, optional heat can be added. Note that this illustration of process and decision flow does not assume or require a particular sequence or timing of events, unless specifically stated.

(25) Upon adding the polyfunctional monomer(s) M.sup.1 115 to the segment 105 of the protein, peptide or other material containing the disulfide bonds 110, the initial reaction is the breaking of the disulfide bond 110 by the disulfide breaking group 120 and reformation of disulfide bond 145 on the segment 105 and formation of a thiol 160 on the segment 165.

(26) FIG. 2 illustrates an example of graft polymerization 200 on a functionalized substrate. Disulfide bonds 210 are the bonds between two cysteine residues that are part of proteins, peptides or other materials 205 containing disulfide bonds. At least one polyfunctional monomer M.sup.1 215 including at least one thiol group 220 and a ring 230 capable of polymerizing upon opening may be added.

(27) Upon adding polyfunctional monomer(s) M.sup.1 215 to the segment 205 of the protein, peptide or other material containing disulfide bonds, the initial reaction is the breaking of the disulfide bond 210 by the thiol 220 and reformation of the disulfide bond 240 on the segment 205 and formation of thiol 250 on the segment 255.

(28) After the disulfide bond reformation has occurred, appropriate conditions are established to open the ring 230 on the monomer. The opened ring 275 is then capable of reacting with other rings on monomers 215, leading to formation of the grafted polymer 295. Polymerization can be initiated by appropriate means using, for example, heat, UV light, catalyst, etc

(29) As one example, the monomer M.sup.1 215 may contain a lactide ring. Upon addition of heat or an appropriate catalyst such as tin (II) chloride, the lactide ring opens and graft polymerization occurs.

(30) FIG. 3 illustrates an embodiment of the overview of a graft polymerization on a functionalized substrate 300. Disulfide bonds 310 are the bonds between two cysteine residues that are part of proteins, peptides or other materials containing disulfide bonds 305. To break the disulfide bond 310 at least one polyfunctional monomer M.sup.1 315 is used. The polyfunctional M.sup.1 315 can include at least one thiol group 320, one A.sup.1 functional group 325 and optionally one A.sup.2 functional group 330 or two functional groups A.sup.2 330 and A.sup.3 335 respectively. Functional groups A.sup.1, A.sup.2, and A.sup.3 may be any functional group of choice dependent upon the target polymer. Furthermore, multiple and different polyfunctional monomers M.sup.1 315 may be added as required dependent upon the polymer to be produced. Note that the polyfunctional monomer(s) is not limited to having three functional groups in addition to the disulfide bond breaking functional group, but may have any number of additional functional groups (A.sup.n).

(31) Upon adding polyfunctional monomer(s) M.sup.1 315 to the segment of the protein, peptide or other material containing disulfide bonds 305 the initial reaction is the breaking of the disulfide bond 310 by the thiol 320 and reformation of the disulfide bond 345 on the segment 305 and formation of thiol 360 on the segment 365. Monomers M.sup.2 355 are added to the initial reaction product 350 and polymerization is initiated by appropriate means such as heat, UV light, catalyst 370 but not limited thereto. The initial propagation step in the polymerization is the addition of monomer M.sup.2 355 to functional groups A.sup.1 325 to form moiety 385, as well as the possible addition to optional functional groups A.sup.2 330 to form moiety 390 and optional functional group A.sup.3 335 to form moiety 395. However, under appropriate conditions addition of monomer M.sup.2 will allow the polymerization reaction to occur eliminating the need for an initiator 370. Furthermore, the process may not require the addition of monomer M.sup.2 355 and polymerization is initiated by appropriate means such as heat, UV light, catalyst 370 but not limited thereto. Note that this illustration of process and decision flow does not assume or require a particular sequence or timing of events, unless specifically stated.

(32) In one example, monomer M.sup.2 355 may be poly-enes, of which the polyfunctional monomer M.sup.1 315 contains a thiol functional group A.sup.1 325 to polymerize a thiol-ene polymer. In some embodiments, the molar ratio of the thiol functional group A.sup.1 325 and the ethylenically unsaturated functional group is not greater than 1:1. 0.1623 grams of dried, clean, chopped chicken feathers are massed in a brown vial. To this, 7.5079 grams of 2-, 2-(ethylenedioxy) diethanethiol are added. The vial is sealed and placed in a 90 C. oven for 24 hours. The vial is then cooled to room temperature before adding 4.7459 grams of acrylic acid and 1.2380 grams of 2-, 4-, 6-trimethyl benzoyl diphenyl phosphine oxide (a UV photoinitiator). The vial is resealed and placed in a 50 C. oven for an hour in order to dissolve the photoinitiator. The vial is cooled to room temperature. The contents are poured onto a sheet of soda float glass and a notch-bar coater is used to prepare a 50 mil thick coating. The coating is then placed under a broad-spectrum UV lamp for about 30 seconds and removed. The coating is cured into a pressure-sensitive adhesive that is tacky.

(33) In another example, the monomer M.sup.2 355 may be a polyol, of which the polyfunctional monomer M.sup.1 315 includes two carboxylic acid groups A.sup.1 325 and A.sup.2 330 to polymerize a polyester polymer. Monomer M.sup.2 355 may be added at the same time as the polyfunctional monomer M.sup.1 315 is added to the protein 305 or may be added after the initial reaction product 350 is formed.

(34) FIG. 4 illustrates an embodiment of the overview of a graft polymerization on a functionalized substrate 400. Disulfide bonds 410 are the bonds between two cysteine residues that are part of proteins, peptides or other materials containing disulfide bonds 405. To break the disulfide bond 410, at least one polyfunctional monomer M.sup.1 415 that includes at least one thiol group 420, one A.sup.1 functional group 425 and optionally one A.sup.2 functional group 430. Functional groups A.sup.1 and A.sup.2 may be any functional group, depending for example, on the target polymer(s) to be formed. Furthermore, multiple and different polyfunctional monomers M.sup.1 415 may be added as required dependent upon the polymer(s) to be produced.

(35) Upon adding polyfunctional monomer(s) M.sup.1 415 to the segment of the protein, peptide or other material containing disulfide bonds 405 the initial reaction is the breaking of the disulfide bond 410 by the thiol 420 and reformation of the disulfide bond 445 on the segment 405 and formation of thiol 460 on the segment 465.

(36) Monomers M.sup.2-1 and M.sup.2-2455 are added to the initial reaction product 450 wherein M.sup.2-1 and M.sup.2-2 may be polymerized at the same time or sequentially. As shown in FIG. 4, one of the initial propagation steps involves the addition of monomer M.sup.2-1 to form moiety 485 with additional propagations steps leading to the formation of polymer.sup.1 710, while another of the initial propagation steps involves the addition of monomer M.sup.2-2 to form moiety 490 with additional propagations steps leading to the formation of polymer.sup.2 705, Polymerization can be initiated by appropriate means such as, for example, heat, UV light, catalyst 470, etc. However, under appropriate conditions addition of monomers M.sup.2-1 and/or M.sup.2-2 can allow the polymerization reaction to occur eliminating the need for an initiator 470.

(37) FIG. 5 illustrates an embodiment of a flowchart 500 for graft polymerization on a functionalized substrate. It is understood that the steps in flowchart 500 can be performed sequentially or in parallel. It is also understood that in some embodiments, the steps in the flowchart 500 can be modified, moved, removed, replaced with additional steps and otherwise customized based on the type of graft polymerization to be performed. At 505, a feedstock containing disulfide bonds is provided. In some embodiments, the feedstock can be a waste product such as feathers. At 510, one or more polyfunctional monomer(s) M.sup.1 510 containing at least one disulfide bond breaking functional group (e.g., a thiol functional group) is added to a disulfide bond-containing feedstock 505 to create a functionalize substrate by breaking the disulfide bonds between the cysteine residues crosslinking the feedstock and reforming new disulfide bonds between one of the cysteine residues of the feedstock and the attacking thiol or other disulfide bond breading group. At 510, other M.sup.1 polyfunctional monomer(s) can be added that may influence the M.sup.2 monomers added at 515, 525, 560 and 575. Optionally, at 520, heat may be added to assist in breaking the disulfide bonds, and the dissolving and mixing of non-liquid monomers and functional groups. Dependent upon the polymer to be produced and without adverse effect on polymerization, at 525, monomer(s) M.sup.2 may be added at the time the polyfunctional monomer(s) M.sup.1 is added to the feedstock at 510. Alternatively, upon completion of the breaking of the disulfide bonds a self-initiating monomer(s) M.sup.2 may be added at 525, at at which time polymerization is initiated at 530.

(38) At 545 and 570, aqueous or non-aqueous solvents may be added as needed prior to initiating polymerization at 555 and accordingly, other M.sup.2 monomers can be added at 560, 580 that are water or non water-soluble. Decisions of when to add M.sup.2 monomers at 550 and 575 as well as decisions to add aqueous or non-aqueous solvents at 540, 565 are determined by the necessary process for the production of the polymer to be produced. Polymerization can be initiated at 555 when all required monomer(s) M.sup.1 510, and monomer(s) M.sup.2 515, 560, 570 have been added to the functionalized substrate. By example, initiation of polymerization 555 may be by the addition of heat, UV, or a catalyst.

(39) Aspects:

(40) It is noted that any of aspects 1-9 below can be combined with any of aspects 10-14.

(41) 1. A process of graft polymerization to generate a graft polymerization composition, comprising:

(42) introducing a disulfide-bond-containing material to a polyfunctional monomer, the disulfide-bond-containing material including a disulfide bond connecting a first portion and a second portion, the polyfunctional monomer including at least one first functional group and at least one second functional group, the first functional group including a disulfide bond breaking material for breaking the disulfide bond and forming a second bond between the first portion and the polyfunctional monomer, the second functional group including a thiol group;

(43) introducing an ene monomer to the disulfide-bond-containing material and a polyfunctional monomer to form a mixture; and

(44) initiating a thiol-ene polymerization reaction of the mixture.

(45) 2. The process of aspect 1, wherein the disulfide bond breaking material includes a thiol group, and the second bond is a disulfide bond.

(46) 3. The process of aspects 1-2, further comprising:

(47) initiating the thiol-ene polymerization reaction of the mixture using an initiator that includes at least one of a UV light, a thermal initiator, and/or a catalyst.

(48) 4. The process of aspects 1-3, further comprising initiating a second polymerization reaction to the graft polymerization composition.

(49) 5. The process of aspects 1-4, wherein the initiating the second polymerization reaction to the graft polymerization composition includes using an initiator that includes at least one of a UV light, a thermal initiator, and/or a catalyst.

(50) 6. The process of aspects 1-4, wherein the initiating the second polymerization reaction to the graft polymerization composition includes introducing a third monomer or macromer to the mixture, and self-initiating, via the third monomer or macromer, a second polymerization reaction.
7. The process of aspects 1-6, wherein the second functional group includes at least one ring, the ring being adapted to be opened to form at least a third functional group.
8. The process of aspects 2-7, wherein a molar ratio of the thiol groups and the ene monomer is not greater than 1:1.
9. The process of aspects 1-7, wherein the first and second portions connected by the disulfide bond are cysteine residues.
10. A graft polymer composition, the composition comprising:

(51) a substrate and a thiol-ene polymer, the substrate and the thiol-ene polymer being bonded via a disulfide-bond;

(52) the substrate including a disulfide-bond-containing material, the disulfide-bond-containing material including a disulfide bond connecting a first portion and a second portion; and

(53) the thiol-ene polymer including a polyfunctional monomer and an ene monomer, the polyfunctional monomer including at least one first functional group and at least one second functional group, the first functional group including a disulfide bond breaking material, and the second functional group including a thiol group configured to react with the ene monomer.

(54) 11. The graft polymer composition of aspect 10, wherein the disulfide bond breaking material includes a thiol group.

(55) 12. The graft polymer composition of aspects 10-11, wherein the second functional group includes at least one of an acid anhydride, an acyl halide, an alcohol, an aldehyde, an alkene, an alkyne, an amine, a carboxylic acid, an ester and/or a thiol.

(56) 13. The graft polymer composition of aspects 10-12, wherein the second functional group includes at least one ring, the ring being adapted to be opened to form at least a third functional group.

(57) 14. The composition of aspects 11-13, wherein a molar ratio of the thiol groups and the ene monomer is not greater than 1:1.

(58) With regard to the foregoing description, it is to be understood that changes may be made in detail, especially in matters of the construction materials employed and the shape, size and arrangement of the parts without departing from the scope of the present invention. It is intended that the specification and depicted embodiment to be considered exemplary only, with a true scope and spirit of the invention being indicated by the broad meaning of the claims.