Modular process for purifying conjugated polymers

Abstract

A process for purifying a conjugated polymer is disclosed herein. The process comprises dissolving a conjugated polymer in a solvent to provide a solution; adding an agent to the solution to produce an impurity laden agent; and removing the impurity laden agent from the solution to produce a purified conjugated polymer; wherein the agent is at least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, modified cellulose, and combinations of any thereof. Also disclosed is a process for analyzing the purity of the purified conjugated polymer. The purified conjugated polymer is dried to form a thin layer, thermally degraded, and subjected to chemical digestion using a mixture of nitric and hydrochloric acid, followed by ICP-MS analysis. The purified conjugated polymer is for use in organic electronic applications and / or devices.

Description

MODULAR PROCESS FOR PURIFYING CONJUGATED POLYMERSCROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application 63 / 511 ,001 , filed June 29, 2023. The contents of the referenced application are incorporated into the present application by reference.BACKGROUND1. Field

[0002] This disclosure relates to the field of chemistry. More specifically, but not exclusively, the present disclosure broadly relates to a process for purifying conjugated polymers. Yet more specifically, but not exclusively, the present disclosure broadly relates to a process for removing impurities from conjugated polymers. The present disclosure also relates to analytical means for use in conjunction with the process for analyzing the purity of the conjugated polymers.2. Related Art

[0003] Conjugated polymers, more specifically conjugated semi-conducting or conducting polymers, are found in several commercial applications such as in organic solar cells, organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs), sensors, photovoltaic cells, batteries, capacitors, and the like. For many of the commercial applications, it is important that the conjugated semi-conducting or conducting polymers do not comprise metal impurities or that the presence of any metal impurities be kept as low as possible for optimal performance. Typical metal impurities include palladium, nickel, magnesium, ruthenium, tin and / or zinc. Indeed, even trace amounts of these metal impurities can adversely impact the performance of devices comprising conjugated conducting polymers. Often, the root cause for the presence of such metal impurities can be found in the synthesis of the conjugated conducting polymers themselves, notwithstanding careful work-up and extensive purification efforts. The metal impurities are often bound, typically ionically, by the functional groups present on the conjugated semi-conducting or conducting polymers and / or entrapped in the polymer matrix.

[0004] Various methods have been utilized in efforts to purify conjugated polymers, such as precipitation, Soxhlet extraction, preparative size exclusion chromatography, dialysis, and column chromatography. However, each of these techniques suffers fromdrawbacks such as significant processing times, labor intensive, the use of significant amounts of solvents, poor scalability, and / or effectiveness.

[0005] Regarding purification by precipitation, the conjugated polymer is precipitated out of a concentrated solution through the addition of a second solvent, a method referred to as “solvent displacement’. However, the resulting polymer will often contain non- negligible amounts of impurities that become trapped in the polymer matrix while the polymer precipitates out of the solution. Moreover, precipitation is often accompanied by product loss as a result of some of the conjugated polymer remaining in solution. Yet moreover, the use of a second solvent increases the total environmental footprint of the precipitation process.

[0006] Regarding purification by Soxhlet extraction, the conjugated polymer is repeatedly washed with one or more hot solvents, resulting in the removal of impurities such as non-reacted monomers, undesired side-products, catalyst or catalytic residues, and low molecular weight oligomers. However, Soxhlet extraction typically entails significant processing times and frequently yields a purified product comprising metal impurities, especially when these metal impurities are entrapped in the polymer matrix and / or adhere strongly thereto.

[0007] Regarding preparative size exclusion chromatography, this method is suitable for removing low molecular weight impurities from the conjugated polymer. However, size exclusion chromatography is rather material intensive and not well suited for large scale operations, at least in view of the costs associated with the gel matrices. Moreover, metal impurities often remain entrapped within the purified conjugated polymer instead of being retained by the gel matrices. Similarly, silica-based chromatography suffers from analogous drawbacks, while also resulting in product losses due to strong adhesion between the polymer and the silica. The scale-up of preparative size exclusion chromatography is rather expensive and as a result the method is relegated to purifying sample sized amounts of products.

[0008] Complexing agents such as N,N-diethyl-2-phenyldiazenecarbothioamide, and chelating agents such as EDTA, 18-crown-6, 8-hydroxquinoline, tetraethylthiuram disulfide, N,N'-bis(salicylidene)ethylenediamine, dimethylglyoxime, 15-crown-5, and poly(N-isopropylacrylamide, have also been used to address metal-based impurities in conjugated polymers. Moreover, scavengers have also been used to address metal-based impurities in conjugated polymers. The scavenger may be in free standing form and includes sodium cyanide (NaCN), potassium cyanide (KCN) andethylenediaminetetraacetic acid (EDTA), or the metal scavenging functional groups, such as a carboxyl, amine, thiol, hydroxyl, amide, nitrile, nitrogen with a free lone pair of electrons, and combinations thereof, may be carried on a solid support or on metal scavenging molecules. However, these complexing agents and / or scavengers are not broadly applicable and are useful only for the removal of selected metal impurities. Moreover, excess complexing agent and / or scavenger subsequently needs to be removed from the purified polymer, typically by multiple water extraction steps, increasing the total environmental footprint in the form of contaminated water.

[0009] Phosphorus-based functionalities linked to an insoluble matrix, such as silica bound diphenyl phosphine, and triphenylphosphine-modified crosslinked polystyrene have also been used to address metal-based impurities in conjugated polymers. Finally, ion exchange resins such as Amberlite, Amberlist, Daiyaion, Duolite, and Sumichelate have been used to address metal-based impurities in conjugated polymers. These matrix and polymer-supported agents and resins are not broadly applicable and are useful only for the removal of selected metal impurities.

[0010] A novel process for purifying conjugated polymers, more specifically conjugated semi-conducting or conducting polymers that is generally applicable to all manner of impurities, inexpensive and / or scalable is of commercial interest. Such purification process advantageously reduces the levels of the impurities to levels acceptable for all manner of organic photovoltaic (OPV) applications, batteries, capacitors, and the like. The purified conjugated semi-conducting or conducting polymers may advantageously provide for enhanced reproducible performance of devices comprising such polymers.SUMMARY

[0011] The present disclosure broadly relates to a process for purifying conjugated polymers. More specifically, but not exclusively, the present disclosure broadly relates to a process for removing metal and / or inorganic impurities from conjugated polymers. Yet more specifically, the present disclosure relates to a process for removing metal and / or inorganic impurities from conjugated semi-conducting or conducting polymers. The present disclosure also relates to analytical means for use in conjunction with the purification process for analyzing the purity of the purified conjugated polymers.

[0012] In an aspect, the present disclosure relates to a process for purifying a conjugated polymer, the process comprising: dissolving a conjugated polymer in a solventto provide a solution; adding an agent to the solution to produce an impurity laden agent; and removing the impurity laden agent from the solution to produce a pregnant solution comprising the purified conjugated polymer; wherein the agent is at least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, modified cellulose, and combinations of any thereof. In an embodiment of the present disclosure, the process further comprises a step of analyzing the purified conjugated polymers for residual impurities. In an embodiment of the present disclosure, the analyzing comprises drying the purified conjugated polymer, thermally degrading the dried purified conjugated polymer and chemically digesting the thermally degraded conjugated polymer. In a further embodiment of the present disclosure, the thermally degrading comprises heating the purified conjugated polymer to a temperature of at least 400°C. In a further embodiment of the present disclosure, the chemical digestion is performed using at least one of nitric and hydrochloric acid. In yet a further embodiment of the present disclosure, the chemical digestion is performed using a mixture of nitric and hydrochloric acid. In yet a further embodiment of the present disclosure, the mixture comprises a molar ratio of about 1 :3 of nitric and hydrochloric acid. In yet a further embodiment of the present disclosure, the digested conjugated polymer is analyzed by inductively coupled plasma mass spectroscopy (ICP-MS). In yet a further embodiment of the present disclosure, the impurities are metal impurities. In yet a further embodiment of the present disclosure, the impurities are transition metal impurities. In yet a further embodiment of the present disclosure, the metal impurities comprise at least one of Li, B, Na, Mg, P, Ti, Fe, Ca, V, Cr, Mn, Co, Ni, Cu, Zn, As, Pd, Ag, Cd, In, Sn, Mo, Cs, Ba, Tl, Pb, K, and Al.

[0013] In an aspect of the present disclosure, the conjugated polymer is contacted with the agent for at least 30 seconds, wherein the agent is at least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, modified cellulose, and combinations of any thereof. In an embodiment of the present disclosure, the conjugated polymer is contacted with the agent for a period ranging from about 5 minutes to about 72 hours.

[0014] In an aspect, the present disclosure relates to a process for purifying a conjugated polymer, the process comprising: circulating a solution comprising a conjugated polymer through a column packed with an agent suitable for removing impurities from the conjugated polymer; and eluding a purified conjugated polymer from the column; wherein the agent is at least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, modifiedcellulose, and combinations of any thereof. In an embodiment of the present disclosure, the process further comprises a step of analyzing the purified conjugated polymers for any residual impurities. In an embodiment of the present disclosure, the analyzing comprises drying the purified conjugated polymer, thermally degrading the dried purified conjugated polymer and chemically digesting the thermally degraded conjugated polymer. In a further embodiment of the present disclosure, the thermally degrading comprises heating the purified conjugated polymer to a temperature of at least 400°C. In a further embodiment of the present disclosure, the chemical digestion is performed using at least one of nitric and hydrochloric acid. In yet a further embodiment of the present disclosure, the chemical digestion is performed using a mixture of nitric and hydrochloric acid. In yet a further embodiment of the present disclosure, the mixture comprises a molar ratio of about 1 :3 of nitric and hydrochloric acid. In yet a further embodiment of the present disclosure, the digested conjugated polymer is analyzed by inductively coupled plasma mass spectroscopy (ICP-MS). In yet a further embodiment of the present disclosure, the impurities are metal impurities. In yet a further embodiment of the present disclosure, the impurities are transition metal impurities. In yet a further embodiment of the present disclosure, the metal impurities comprise at least one of Li, B, Na, Mg, P, Ti, Fe, Ca, V, Cr, Mn, Co, Ni, Cu, Zn, As, Pd, Ag, Cd, In, Sn, Mo, Cs, Ba, TI, Pb, K, and Al.

[0015] In an aspect, the present disclosure relates to purified conjugated polymers for use in organic electronic applications and / or devices. In an embodiment of the present disclosure, the organic electronic applications and / or devices comprise organic solar cells (OPVs), organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs), sensors, photovoltaic cells, batteries, and / or capacitors.

[0016] Also disclosed in the context of the present disclosure are embodiments 1 to 105. Embodiment 1 is a process for purifying a conjugated polymer, the process comprising: dissolving a conjugated polymer in a solvent to provide a solution; adding an agent to the solution to produce an impurity laden agent; and removing the impurity laden agent from the solution to produce a pregnant solution comprising the purified conjugated polymer; wherein the agent is at least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, modified cellulose, and combinations of any thereof. Embodiment 2 is the process of embodiment 1 , further comprising stirring the solution following the addition of the agent. Embodiment 3 is the process of embodiment 1 or 2, wherein the solution has a temperature ranging from about -20°C to about 200°C. Embodiment 4 is the process of embodiment 3, wherein the solution has a temperature ranging from about 20°C to about 180°C. Embodiment 5is the process of embodiment 1 or 2, wherein the solution is subjected to a temperature gradient, wherein the temperature ranges from about 0°C to about 200°C. Embodiment 6 is the process of embodiment 5, wherein the temperature ranges from about 20°C to about 180°C. Embodiment 7 is the process of any one of embodiments 1 to 6, wherein the conjugated polymer is contacted with the agent for at least 30 seconds. Embodiment 8 is the process of embodiment 7, wherein the conjugated polymer is contacted with the agent for a period ranging from about 5 minutes to about 72 hours. Embodiment 9 is the process of any one of embodiments 1 to 8, wherein the solvent comprises at least one of chlorobenzenes, xylenes, chloroform, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof. Embodiment 10 is the process of any one of embodiments 1 to 9, wherein the metal scavenger resin is at least one of a trimercaptotriazine and a sodium triaminetetraacetate functionalized resin. Embodiment 11 is the process of any one of embodiments 1 to 10, wherein the ion exchange resin is an acidic and / or basic ion exchange resin. Embodiment 12 is the process of embodiment 11 , wherein the acidic ion exchange resin comprises Amberlyst® 15, Amberlyst® 36, AmberChrom® 50WX2, Dowex® 50WX4, Lewatit® TP 207 and Sephadex® C-50. Embodiment 13 is the process of embodiment 11 , wherein the basic ion exchange resin comprises Amberlite® HPR4811 Cl, Amberlite® FPA66, AmberTec® UP550 OH, Diaion® WA30, Amberlyst® A26 and AmberChrom® 1X8. Embodiment 14 is the process of any one of embodiments 1 to 13, wherein the mass ratio (w / w) of agent to conjugated polymer is at least 0.01 :1.0. Embodiment 15 is the process of any one of embodiments 1 to 13, wherein the mass ratio (w / w) of agent to conjugated polymer ranges from about 0.01 :1.0 to about 100.0:1.0. Embodiment 16 is the process of any one of embodiments 1 to 15, wherein the impurity laden agent is removed from the solution by filtration, decantation or centrifugation to produce an isolated impurity laden agent. Embodiment 17 is the process of embodiment 16, wherein the filtration is complemented by a filtration aid. Embodiment 18 is the process of embodiment 17, wherein the filtration aid is at least one of silica, alumina, diatomaceous earth, charcoal, sand, and combinations of any thereof. Embodiment 19 is the process of embodiment 18, wherein the filtration aid is Celite®. Embodiment 20 is the process of any one of embodiments 16 to 19, wherein the isolated impurity laden agent is extracted with a solvent to remove any unreacted agent. Embodiment 21 is the process of embodiment 20, wherein the extraction is performed once or multiple times. Embodiment 22 is the process of embodiment 20 or 21 , wherein the solvent is at least one of chlorobenzenes, xylenes, chloroform, acetone, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof. Embodiment 23 is the process of embodiment 21 , wherein the multiple extractions are performed usingthe same solvent or different solvents. Embodiment 24 is the process of embodiment 23, wherein the solvent or solvents are at least one of chlorobenzenes, xylenes, chloroform, acetone, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof. Embodiment 25 is the process of any one of embodiments 20 to 24, wherein the extraction is performed at temperatures ranging from about -20°C to about 200°C. Embodiment 26 is the process of embodiment 25, wherein the extraction is performed at temperatures ranging from about 20°C to about 180°C. Embodiment 27 is the process of any one of embodiments 1 to 26, wherein the purified conjugated polymer is isolated by precipitation using solvent displacement. Embodiment 28 is the process of embodiment 27, wherein the solvent displacement is performed using at least one of methanol, ethanol isopropanol, acetone, pentane and hexanes. Embodiment 29 is the process of any one of embodiments 1 to 26, wherein the purified conjugated polymer is isolated by concentrating the pregnant solution. Embodiment 30 is the process of any one of embodiments 1 to 29, further comprising a step of analyzing the purified conjugated polymer for any residual impurities. Embodiment 31 is the process of embodiment 30, wherein the analyzing comprises drying the purified conjugated polymer, thermally degrading the dried purified conjugated polymer and chemically digesting the thermally degraded conjugated polymer. Embodiment 32 is the process of embodiment 31 , wherein thermally degrading comprises heating the purified conjugated polymer to a temperature of at least 400°C. Embodiment 33 is the process of embodiment 31 , wherein the chemical digesting is performed using at least one of nitric and hydrochloric acid. Embodiment 34 is the process of embodiment 31 , wherein the chemical digesting is performed using a mixture of nitric and hydrochloric acid. Embodiment 35 is the process of embodiment 34, wherein the mixture comprises a molar ratio of about 1 :3 of nitric and hydrochloric acid. Embodiment 36 is the process of any one of embodiments 31 to 35, wherein the digested conjugated polymer is analyzed by inductively coupled plasma mass spectroscopy (ICP-MS). Embodiment 37 is the process of any one of embodiments 1 to 36, wherein the impurities are metal impurities.

[0017] Embodiment 38 is a process for purifying a conjugated polymer, the process comprising: circulating a solution comprising a conjugated polymer through a column packed with an agent suitable for removing impurities from the conjugated polymer; and eluding a solution comprising a purified conjugated polymer from the column; wherein the agent is at least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, modified cellulose, and combinations of any thereof. Embodiment 39 is the process of embodiment 38, wherein the solution comprising the conjugated polymer is circulated through the agent-packedcolumn in a closed-loop. Embodiment 40 is the process of embodiment 38 or 39, wherein the solution comprising the conjugated polymer has a temperature ranging from about - 20°C to about 200°C. Embodiment 41 is the process of embodiment 40, wherein the solution comprising the conjugated polymer has a temperature ranging from about 20°C to about 180°C. Embodiment 42 is the process of embodiment 40 or 41 , wherein the solution comprising the conjugated polymer is subjected to a temperature gradient, wherein the temperature ranges from about 0°C to about 200°C. Embodiment 43 is the process of embodiment 42, wherein the temperature ranges from about 20°C to about 180°C. Embodiment 44 is the process of any one of embodiments 38 to 43, wherein the solution comprising the conjugated polymer is circulated through the agent-packed column over a period ranging from about 5 minutes to about 72 hours. Embodiment 45 is the process of any one of embodiments 38 to 44, wherein the solution comprising the conjugated polymer comprises at least one solvent selected from chlorobenzenes, xylenes, chloroform, acetone, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof. Embodiment 46 is the process of any one of embodiments 38 to 45, wherein the metal scavenger resin is at least one of a trimercaptotriazine and a sodium triaminetetraacetate functionalized resin. Embodiment 47 is the process of any one of embodiments 38 to 46, wherein the ion exchange resin is an acidic and / or basic ion exchange resin. Embodiment 48 is the process of embodiment 47, wherein the acidic ion exchange resin comprises Amberlyst® 15, Amberlyst® 36, AmberChrom® 50WX2, Dowex® 50WX4, Lewatit® TP 207 and Sephadex® C-50. Embodiment 49 is the process of embodiment 47, wherein the basic ion exchange resin comprises Amberlite® HPR4811 Cl, Amberlite® FPA66, AmberTec® UP550 OH, Diaion® WA30, Amberlyst® A26 and AmberChrom® 1X8. Embodiment 50 is the process of any one of embodiments 38 to 49, wherein the purified conjugated polymer is isolated by precipitation using solvent displacement. Embodiment 51 is the process of embodiment 50, wherein the solvent displacement is performed using at least one of methanol, ethanol, isopropanol, acetone, pentane and hexanes. Embodiment 52 is the process of any one of embodiments 38 to 49, wherein the purified conjugated polymer is isolated by concentrating the solution comprising the purified conjugated polymer. Embodiment 53 is the process of any one of embodiments 38 to 52, further comprising a step of analyzing the purified conjugated polymer for any residual impurities. Embodiment 54 is the process of embodiment 53, wherein the analyzing comprises drying the purified conjugated polymer, thermally degrading the dried purified conjugated polymer and chemically digesting the thermally degraded conjugated polymer. Embodiment 55 is the process of embodiment 54, wherein thermally degrading comprises heating the purified conjugated polymer to a temperatureof at least 400°C. Embodiment 56 is the process of embodiment 54, wherein the chemical digesting is performed using at least one of nitric and hydrochloric acid. Embodiment 57 is the process of embodiment 54, wherein the chemical digesting is performed using a mixture of nitric and hydrochloric acid. Embodiment 58 is the process of embodiment 57, wherein the mixture comprises a molar ratio of about 1 :3 of nitric and hydrochloric acid. Embodiment 59 is the process of any one of embodiments 54 to 58, wherein the digested conjugated polymer is analyzed by inductively coupled plasma mass spectroscopy (ICP- MS). Embodiment 60 is the process of any one of embodiments 38 to 59, wherein the impurities are metal impurities.

[0018] Embodiment 61 is a process for purifying a conjugated polymer, the process comprising: dissolving a conjugated polymer in a solvent to provide a solution; adding an agent to the solution to produce an impurity laden agent; removing the impurity laden agent from the solution to produce a pregnant solution comprising the purified conjugated polymer; and analyzing the purified conjugated polymer for any residual impurities, wherein the agent is at least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, modified cellulose, and combinations of any thereof. Embodiment 62 is the process of embodiment 61 , further comprising stirring the solution following the addition of the agent. Embodiment 63 is the process of embodiment 61 or 62, wherein the solution has a temperature ranging from about -20°C to about 200°C. Embodiment 64 is the process of embodiment 63, wherein the solution has a temperature ranging from about 20°C to about 180°C. Embodiment 65 is the process of embodiment 61 or 62, wherein the solution is subjected to a temperature gradient, wherein the temperature ranges from about 0°C to about 200°C. Embodiment 66 is the process of embodiment 65, wherein the temperature ranges from about 20°C to about 180°C. Embodiment 67 is the process of any one of embodiments 61 to 66, wherein the conjugated polymer is contacted with the agent for at least 30 seconds. Embodiment 68 is the process of embodiment 67, wherein the conjugated polymer is contacted with the agent for a period ranging from about 5 minutes to about 72 hours. Embodiment 69 is the process of any one of embodiments 61 to 68, wherein the solvent comprises at least one of chlorobenzenes, xylenes, chloroform, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof. Embodiment 70 is the process of any one of embodiments 61 to 69, wherein the metal scavenger resin is at least one of a trimercaptotriazine and a sodium triaminetetraacetate functionalized resin. Embodiment 71 is the process of any one of embodiments 61 to 70, wherein the ion exchange resin is an acidic and / or basic ion exchange resin. Embodiment 72 is the process of embodiment71 , wherein the acidic ion exchange resin comprises Amberlyst® 15, Amberlyst® 36, AmberChrom® 50WX2, Dowex® 50WX4, Lewatit® TP 207 and Sephadex® C-50. Embodiment 73 is the process of embodiment 71 , wherein the basic ion exchange resin comprises Amberlite® HPR4811 Cl, Amberlite® FPA66, AmberTec® UP550 OH, Diaion® WA30, Amberlyst® A26 and AmberChrom® 1X8. Embodiment 74 is the process of any one of embodiments 61 to 73, wherein the mass ratio (w / w) of agent to conjugated polymer is at least 0.01 :1.0. Embodiment 75 is the process of any one of embodiments 61 to 73, wherein the mass ratio (w / w) of agent to conjugated polymer ranges from about 0.01 :1.0 to about 100.0: 1 .0. Embodiment 76 is the process of any one of embodiments 61 to 75, wherein the impurity laden agent is removed from the solution by filtration, decantation or centrifugation to produce an isolated impurity laden agent. Embodiment 77 is the process of embodiment 76, wherein the filtration is complemented by a filtration aid. Embodiment 78 is the process of embodiment 77, wherein the filtration aid is at least one of silica, alumina, diatomaceous earth, charcoal, sand, and combinations of any thereof. Embodiment 79 is the process of embodiment 78, wherein the filtration aid is Celite®. Embodiment 80 is the process of any one of embodiments 76 to 79, wherein the isolated impurity laden agent is extracted with a solvent to remove any unreacted agent. Embodiment 81 is the process of embodiment 80, wherein the extraction is performed once or multiple times. Embodiment 82 is the process of embodiment 80 or 81 , wherein the solvent is at least one of chlorobenzenes, xylenes, chloroform, acetone, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof. Embodiment 83 is the process of embodiment 81 , wherein the multiple extractions are performed using the same solvent or different solvents. Embodiment 84 is the process of embodiment 83, wherein the solvent or solvents are at least one of chlorobenzenes, xylenes, chloroform, acetone, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof. Embodiment 85 is the process of any one of embodiments 80 to 84, wherein the extraction is performed at temperatures ranging from about -20°C to about 200°C. Embodiment 86 is the process of embodiment 85, wherein the extraction is performed at temperatures ranging from about 20°C to about 180°C. Embodiment 87 is the process of any one of embodiments 61 to 86, wherein the purified conjugated polymer is isolated by precipitation using solvent displacement. Embodiment 88 is the process of embodiment 87, wherein the solvent displacement is performed using at least one of methanol, ethanol isopropanol, acetone, pentane and hexanes. Embodiment 89 is the process of any one of embodiments 61 to 86, wherein the purified conjugated polymer is isolated by concentrating the pregnant solution. Embodiment 90 is the process of embodiment 61 , wherein the analyzing comprises drying the purified conjugated polymer, thermallydegrading the dried purified conjugated polymer and chemically digesting the thermally degraded conjugated polymer. Embodiment 91 is the process of embodiment 90, wherein thermally degrading comprises heating the purified conjugated polymer to a temperature of at least 400°C. Embodiment 92 is the process of embodiment 90, wherein the chemical digesting is performed using at least one of nitric and hydrochloric acid. Embodiment 93 is the process of embodiment 90, wherein the chemical digesting is performed using a mixture of nitric and hydrochloric acid. Embodiment 94 is the process of embodiment 93, wherein the mixture comprises a molar ratio of about 1 :3 of nitric and hydrochloric acid. Embodiment 95 is the process of any one of embodiments 90 to 94, wherein the digested conjugated polymer is analyzed by inductively coupled plasma mass spectroscopy (ICP- MS). Embodiment 96 is the process of any one of embodiments 61 to 95, wherein the impurities are metal impurities. Embodiment 97 is the process of any one of embodiments 1 to 96, wherein the purified conjugated polymer is for use in organic electronic applications and / or devices. Embodiment 98 is the process of embodiment 97, wherein the organic electronic applications and / or devices comprise organic solar cells (OPVs), organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs), sensors, photovoltaic cells, batteries, and / or capacitors.

[0019] Embodiment 99 is a method for analyzing a conjugated polymer for impurities, the method comprising: drying the conjugated polymer to form a thin film; thermally degrading the dried purified conjugated polymer thin film; and chemically digesting the thermally degraded conjugated polymer. Embodiment 100 is the method of embodiment 99, wherein thermally degrading comprises heating the conjugated polymer to a temperature of at least 400°C. Embodiment 101 is the method of embodiment 99, wherein the chemical digesting is performed using at least one of nitric and hydrochloric acid. Embodiment 102 is the method of embodiment 99, wherein the chemical digesting is performed using a mixture of nitric and hydrochloric acid. Embodiment 103 is the method of embodiment 102, wherein the mixture comprises a molar ratio of about 1 :3 of nitric and hydrochloric acid. Embodiment 104 is the method of any one of embodiments 99 to 103, wherein the digested conjugated polymer is analyzed by inductively coupled plasma mass spectroscopy (ICP-MS). Embodiment 105 is the method of any one of embodiments 99 to 104, wherein the thin film has a thickness not exceeding 1 mm.

[0020] The word “a” or “an” when used in conjunction with the term “comprising” in the claims and / or the specification may mean “one”, but it is also consistent with the meaning of “one or more”, “at least one”, and “one or more than one” unless the content clearlydictates otherwise. Similarly, the word “another” may mean at least a second or more unless the content clearly dictates otherwise.

[0021] As used in this specification and claim(s), the words “comprising” (and any form of comprising, such as “comprise” and “comprises”), “having” (and any form of having, such as “have” and “has”), “including” (and any form of including, such as “include” and “includes”) or “containing” (and any form of containing, such as “contain” and “contains”), are inclusive or open-ended and do not exclude additional, unrecited elements or process steps.

[0022] As used in this specification and claim(s), the word “consisting” and its derivatives, are intended to be close ended terms that specify the presence of stated features, elements, components, groups, integers, and / or steps, and also exclude the presence of other unstated features, elements, components, groups, integers and / or steps.

[0023] The term “consisting essentially of’, as used herein, is intended to specify the presence of the stated features, elements, components, groups, integers, and / or steps as well as those that do not materially affect the basic and novel characteristic(s) of these features, elements, components, groups, integers, and / or steps.

[0024] The terms “about”, “substantially” and “approximately” as used herein mean a reasonable amount of deviation of the modified term such that the end result is not significantly changed. These terms of degree should be construed as including a deviation of at least ±5% of the modified term if this deviation would not negate the meaning of the word it modifies.

[0025] The term “agent”, as used herein, refers to any compound, material or other that is capable of removing impurities from conjugated polymers. The compound, material or other may remove the impurities by adsorption, complexation or other chemical interaction therewith. In an embodiments of the present disclosure, the compound, material or other may selectively remove certain impurities such as metal impurities. In an embodiment of the present disclosure, the agent is at least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, modified cellulose, and combinations of any thereof. After the removal of the impurities, the agent is referred to as an impurity laden agent.

[0026] The term “conjugated polymer”, as used herein, refers to materials comprising a backbone of alternating single and multiple bonds resulting in 7c-conjugation by overlapof the 7c-orbitals, giving rise to a continuum of energy states called band structure. The alternating single and multiple bonds making-up a conjugated binding system or backbone may comprise double bonds, aromatic or heteroaromatic rings, or triple bonds. The conjugated polymers exhibit semiconducting or conducting properties useful in the manufacture of electronic devices such as organic solar cells (OPVs), organic lightemitting diodes (OLEDs), organic field-effect transistors (OFETs), sensors, photovoltaic cells, batteries, and / or capacitors.

[0027] The term “modified cellulose”, as used herein, refers to chemical changes made primarily to the hydroxyl groups in the cellulose backbone. Each cellulose unit contains both primary and secondary hydroxyl groups, with the primary C6-hydroxyl group exhibiting higher reactivity. Non-limiting examples of modified cellulose include methylcellulose (MC), carboxymethyl cellulose (CMC), and microcrystalline cellulose (MCC).

[0028] The foregoing and other advantages and features of the present disclosure will become more apparent upon reading of the following non-restrictive detailed description of illustrative embodiments thereof, with reference to the accompanying drawings / figures. It should be understood, however, that the detailed description and the illustrative embodiments, while indicating specific embodiments of the disclosure, are given by way of illustration only, since various changes and modifications within the spirit and scope of the disclosure will become apparent to those skilled in the art from this description.BRIEF DESCRIPTION OF THE DRAWINGS / FIGURES

[0029] The following figure(s) / drawing(s) form part of the present specification and are included to further demonstrate certain aspects of the present specification. The present specification may be better understood by reference to one or more of these figure(s) / drawing(s) in combination with the detailed description. In the appended drawing(s) / figure(s):

[0030] FIG. 1 - Illustration of selected conjugated polymers P1-P5 in accordance with embodiments of the present disclosure.DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0031] The present disclosure broadly relates to a process for purifying conjugated polymers. More specifically, but not exclusively, the present disclosure broadly relates to a process for removing metal and / or inorganic impurities from conjugated polymers. Yetmore specifically, the present disclosure relates to a process for removing metal and / or inorganic impurities from conjugated semi-conducting or conducting polymers. The present disclosure also relates to analytical means for use in conjunction with the purification process for analyzing the purity of the purified conjugated polymers.

[0032] Conjugated polymers often comprise residual impurities difficult to remove by standard purification procedures. These residual impurities may comprise unreacted starting materials such as unreacted monomeric materials, residual catalyst, and / or residual ligand. Moreover, some of the impurities may arise from impurities already contained in the raw materials and / or solvents. The presence of these impurities may adversely impact the performance of the conjugated polymers, especially when used in devices such as organic solar cells (OPVs), organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs), sensors, and / or photovoltaic cells. In an embodiment of the present disclosure, the impurities are metal impurities. In yet a further embodiment of the present disclosure, the impurities are transition metal impurities. In yet a further embodiment of the present disclosure, the metal impurities comprise at least one of Li, B, Na, Mg, P, Ti, Fe, Ca, V, Cr, Mn, Co, Ni, Cu, Zn, As, Pd, Ag, Cd, In, Sn, Mo, Cs, Ba, Tl, Pb, K, and Al.

[0033] Typical synthetic processes for the preparation of conjugated polymers comprise palladium or nickel-catalyzed cross-coupling reactions to create C-C bonds between aromatic, alkenyl or alkynyl carbons. At least in this aspect, such processes are different from those employed to prepare non-conjugated polymers. As a result, the purification procedures aimed at purifying conjugated polymers need to take into account the removal of a different set of impurities, such as those generated by the use of palladium or nickel catalysts.

[0034] Due in part to their conjugated nature, the presence of heteroatoms and a variety of functional groups installed to modulate the photovoltaic properties of a great many conjugated polymers, significant interactions are typically observed within a particular chain and / or between neighboring chains, resulting in the formation of aggregates. As a result, conjugated polymers exhibit a greater propensity to retain impurities within these aggregates, making any purification process significantly more challenging. Indeed, the presence of any residual palladium or nickel, may further facilitate the formation of such aggregates by interacting with the conjugated structure, heteroatoms and / or functional groups. The formation of such aggregates may result in the entrapment of additional impurities such as any unreacted monomeric materials, residual catalyst,and / or residual ligand. Considering their unique application as semiconductor materials in organic solar cells (OPVs), organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs), sensors, batteries, capacitors, and the like, conjugated polymers require a high degree of purity in order to provide optimal and reproducible performance in such commercial applications.

[0035] EXAMPLES

[0036] The following examples are included to demonstrate preferred embodiments of the disclosure. It should be appreciated by those of skill in the art that the techniques disclosed in the examples which follow represent techniques discovered by the inventors to function well in the practice of the invention, and thus can be considered to constitute preferred modes for its practice. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the disclosure.

[0037] EXAMPLE 1 - General purification procedure A

[0038] A conjugated polymer was weighed and added to a round bottom flask followed by the addition of a suitable solvent to produce a solution. At least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, and modified cellulose was then added to the solution. The mass ratio (w / w) of agent to conjugated polymer ranges from about 0.01 :1.0 to about 100.0:1.0. The resulting mixture was subsequently stirred over a period of time ranging from about 5 minutes to about 72 hours. The temperature of the solution was maintained between about 20°C to about 200°C. Finally, the mixture was filtered, optionally complemented by a filtration aid. The conjugated polymer may be advantageously obtained from the filtrate by concentrating the latter or by solvent displacement. The purity of the conjugated polymer was then analyzed by drying the purified conjugated polymer, thermally degrading the dried purified conjugated polymer, chemically digesting the thermally degraded conjugated polymer, and analyzing the digested conjugated polymer by inductively coupled plasma mass spectroscopy (ICP-MS).

[0039] EXAMPLE 2 - Purification of P1

[0040] P1 (1 g) was added to a round bottom flask, followed by the addition of toluene(50 mL) to produce a solution. An ion exchange resin (Amberlyst® 15; 3 g) was then added to the solution and the resulting mixture stirred over a period of 24 hours at 90°C.The mixture was then filtered over a pad of Celite® 545 or Celite® 512 (~1 cm). The Celite was first wetted with a small amount of toluene prior to the addition of the mixture. The filtrate comprising the purified conjugated polymer P1 was collected in a clean Erlenmeyer flask and slowly transferred to a round bottom flask containing methanol (250 ml) resulting in the precipitation of P1. The toluene / methanol mixture was stirred for 30 minutes to ensure complete precipitation of P1. P1 was isolated using a solvent-resistant vacuum filtration membrane and washed with a small amount of methanol. Finally, P1 was dried under vacuum over a period of 15 hours. The metal impurity analysis for crude P1 and purified P1 , in accordance with an embodiment of the present disclosure, is illustrated in Table 1. The metal impurity analysis for crude P1 and purified P1 using different agents, in accordance with an embodiment of the present disclosure, is illustrated in Table 2.

[0041] Table 1 : Metal impurity analysis for crude and purified P1 by ICP-MS.

[0042] Table 2: Metal impurity analysis for crude and purified P1 by ICP-MS.

[0043] EXAMPLE 3 - General purification procedure B

[0044] A column was packed with at least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, and modified cellulose. A solution comprising a conjugated polymer to be purified is subsequently passed through the column over a period of time ranging from about 5 minutes to about 72 hours using a closed circuit, providing for multiple passages through the column. The time can be adjusted based on factors such as column size ( / .e., quantity of packing agent), amount of impurities, and amount of polymer requiring purification. The temperature of the solution is maintained between about 20°C to about 200°C. The purified conjugated polymer may be advantageously obtained from the solution by concentrating the latter or by solvent displacement. The purity of the conjugated polymer is then analyzed by drying the purified conjugated polymer, thermally degrading the dried purified conjugated polymer, chemically digesting the thermally degraded conjugated polymer, and analyzing the digested conjugated polymer by inductively coupled plasma mass spectroscopy (ICP-MS).

[0045] EXAMPLE 4 - Purification of P1

[0046] P1 (1 g) was added to a round bottom flask, followed by the addition of toluene(50 mL) to produce a solution. A column was packed with a metal scavenger (SiliaMetS® Thiol, 3 g) and the solution was circulated through the column over a period of 5 hours using a closed circuit, providing for multiple passages through the column. The temperature of the solution is maintained between about 80°C to about 110°C. The solution comprising the purified P1 was then slowly transferred to a round bottom flask containing methanol (250 ml) resulting in the precipitation of P1. The toluene / methanol mixture was stirred for 30 minutes to ensure complete precipitation of P1. P1 was isolated using a solvent-resistant vacuum filtration membrane and washed with a small amount of methanol. Finally, P1 was dried under vacuum over a period of 15 hours.

[0047] EXAMPLE 5 - Purification of P1

[0048] P1 (10 g) was added to a round-bottom flask, followed by the addition of toluene (500 mL). The mixture was heated and stirred at temperatures ranging from about 50°C to about 110°C. A column was packed with a metal scavenger (SiliaMetS® Thiol, 30 g), and the solution was circulated through the column over a period of 5 hours using a closed circuit, allowing for multiple passages through the column. The temperature of the solution was maintained between about 80°C and about 110°C. The solution was then passedthrough a subsequent column packed with silica gel particles (250 g), and circulated through the column over a period of 1.5 hours. In an embodiment, the solution may be passed through the second column using a closed circuit, allowing for multiple passages therethrough. At the exit of the column, the hot solution was collected in a flask containing a mixture of methanol and water, resulting in the precipitation of P1. The solution containing the precipitate of P1 was then pumped through a further column containing a stainless steel metal mesh filter. Hot acetone followed by hot hexane were passed through the column in a closed system. Finally, P1 was transferred from the column to a clean container and dried under vacuum for a period of 15 hours.

[0049] EXAMPLE 6 - General purification procedure A (Scale-up)

[0050] A conjugated polymer was weighed and added to a reactor vessel followed by the addition of a suitable solvent to produce a solution. At least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, and modified cellulose was then added to the solution. The mass ratio (w / w) of agent to conjugated polymer ranges from about 0.01 :1.0 to about 100.0:1.0. The resulting mixture was subsequently stirred over a period of time ranging from about 5 minutes to about 72 hours. The temperature of the reactor was maintained between about 20°C to about 200°C. Finally, the mixture was removed from the reactor and filtered, optionally complemented by a filtration aid. The filtrate was then returned to the reactor followed by the addition of a non-solvent to precipitate the purified polymer.

[0051] EXAMPLE 7 - Purification of P5

[0052] P5 (54 g) was added to a reactor vessel (10 L) followed by the addition of chlorobenzene (2.5 L). A metal scavenger resin (MP-Piperazinomethyl Resin, 54 g) and Silica gel (60 - 200 pm, 162 g) were then added to the solution in the reactor. The resulting mixture was subsequently stirred over a period of 16 hours. The temperature of the solution is maintained between about 80°C to about 110°C. The mixture was then removed from the reactor vessel and transferred to one or more centrifuge containers and separated by centrifugation for 30 minutes and filtered. The filtrate was then returned to the reactor vessel followed by the slow addition of methanol under stirring to precipitate purified P5. An additional amount of methanol (1 L) was added, followed by stirring over a period of 30 minutes, to ensure the complete precipitation of P5. P5 was isolated using a solvent-resistant vacuum filtration membrane and washed with a small amount of methanol. Finally, P5 was dried under vacuum over a period of 15 hours.

[0053] Conjugated polymers have a tendency to graphitize during thermal degradation, rendering the subsequent chemical digestion difficult and incomplete. This problem can be advantageously addressed by the formation of a thin film prior to thermal degradation. A thin film advantageously provides for increased contact with O2 during the thermal degradation process. As a result of the reduced graphitization, the resulting ash can be completely digested such as by a mixture of nitric and hydrochloric acid (1 :3 aqua regia HNO3:HCI).

[0054] EXAMPLE 8 - Sample Preparation for ICP-MS Analysis

[0055] A sample of purified conjugated polymer was solubilized in a suitable solvent (e.g., chlorobenzene). The solution was then slowly evaporated until a thin film of conjugated polymer was formed. In an embodiment of the present disclosure, the thin film has a thickness not exceeding 1 mm. The evaporation may be performed under heating. The thin layer of conjugated polymer was then subjected to thermal degradation by heating in an oven at a temperature of at least 400°C. In an embodiment of the present disclosure, the conjugated polymer was subjected to a thermal degradation temperature of 600°C over a period of time ranging from about 1 to 3 hours. After the degraded polymer has cooled down to room temperature, a mixture of nitric and hydrochloric acid (1 :3 aqua regia HNO3:HCI) was added in order to effect the chemical digestion. In an embodiment of the present disclosure, the chemical digestion may be advantageously performed over a period of 1-12 hours. In yet a further embodiment of the present disclosure, the chemical digestion is performed at a temperature of 50°C. The degraded and digested product was taken-up in Milli-Q water and analyzed for its impurity content using ICP-MS. The purity analysis for various conjugated polymers, purified in accordance with an embodiment of the present disclosure is illustrated in Table 3.

[0056] All of the processes and / or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the processes and / or methods of this disclosure have been described in terms of preferred embodiments, it will be apparent to those of skill in the art that variations may be applied thereto such as in the steps or in the sequence of steps of the processes described herein without departing from the concept, spirit, and scope of the disclosure. More specifically, it will be apparent that certain agents which are chemically related may be substituted for the agents described herein while the same or similar results would be achieved. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the disclosure as defined by the appended claims.

[0057] Table 3: Metal impurity analysis for different conjugated polymers P1-P5 by ICP-MS.References1. US 9,045,596 B22. Shcherbyna, S., Diethard, K.B. & Vladimir, I.B. Application of Inductively Coupled Plasma - Mass Spectrometry (ICP-MS) for Analysis of Novel Organic Semiconductor Materials. MRS Online Proceedings Library 937, 0937-M03-02 (2006). https: / / doi.Org / 10.1557 / PROC-0937-M03-02

Claims

CLAIMS1. A process for purifying a conjugated polymer, the process comprising: dissolving a conjugated polymer in a solvent to provide a solution; adding an agent to the solution to produce an impurity laden agent; and removing the impurity laden agent from the solution to produce a pregnant solution comprising the purified conjugated polymer; wherein the agent is at least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, modified cellulose, and combinations of any thereof.

2. The process of claim 1 , further comprising stirring the solution following the addition of the agent.

3. The process of claim 1 or 2, wherein the solution has a temperature ranging from about -20°C to about 200°C.

4. The process of claim 3, wherein the solution has a temperature ranging from about 20°C to about 180°C.

5. The process of claim 1 or 2, wherein the solution is subjected to a temperature gradient, wherein the temperature ranges from about 0°C to about 200°C.

6. The process of claim 5, wherein the temperature ranges from about 20°C to about 180°C.

7. The process of any one of claims 1 to 6, wherein the conjugated polymer is contacted with the agent for at least 30 seconds.

8. The process of claim 7, wherein the conjugated polymer is contacted with the agent for a period ranging from about 5 minutes to about 72 hours.

9. The process of any one of claims 1 to 8, wherein the solvent comprises at least one of chlorobenzenes, xylenes, chloroform, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof.

10. The process of any one of claims 1 to 9, wherein the metal scavenger resin is at least one of a trimercaptotriazine and a sodium triaminetetraacetate functionalized resin.

11. The process of any one of claims 1 to 10, wherein the ion exchange resin is an acidic and / or basic ion exchange resin.

12. The process of claim 11 , wherein the acidic ion exchange resin comprises Amberlyst® 15, Amberlyst® 36, AmberChrom® 50WX2, Dowex® 50WX4, Lewatit® TP 207 and Sephadex® C-50.

13. The process of claim 11 , wherein the basic ion exchange resin comprises Amberlite® HPR4811 Cl, Amberlite® FPA66, AmberTec® UP550 OH, Diaion® WA30, Amberlyst® A26 and AmberChrom® 1X8.

14. The process of any one of claims 1 to 13, wherein the mass ratio (w / w) of agent to conjugated polymer is at least 0.01 :1.0.

15. The process of any one of claims 1 to 13, wherein the mass ratio (w / w) of agent to conjugated polymer ranges from about 0.01 :1.0 to about 100.0:1.0.

16. The process of any one of claims 1 to 15, wherein the impurity laden agent is removed from the solution by filtration, decantation or centrifugation to produce an isolated impurity laden agent.

17. The process of claim 16, wherein the filtration is complemented by a filtration aid.

18. The process of claim 17, wherein the filtration aid is at least one of silica, alumina, diatomaceous earth, charcoal, sand, and combinations of any thereof.

19. The process of claim 18, wherein the filtration aid is Celite®.

20. The process of any one of claims 16 to 19, wherein the isolated impurity laden agent is extracted with a solvent to remove any unreacted agent.

21. The process of claim 20, wherein the extraction is performed once or multiple times.

22. The process of claim 20 or 21 , wherein the solvent is at least one of chlorobenzenes, xylenes, chloroform, acetone, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof.

23. The process of claim 21 , wherein the multiple extractions are performed using the same solvent or different solvents.

24. The process of claim 23, wherein the solvent or solvents are at least one of chlorobenzenes, xylenes, chloroform, acetone, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof.

25. The process of any one of claims 20 to 24, wherein the extraction is performed at temperatures ranging from about -20°C to about 200°C.

26. The process of claim 25, wherein the extraction is performed at temperatures ranging from about 20°C to about 180°C.

27. The process of any one of claims 1 to 26, wherein the purified conjugated polymer is isolated by precipitation using solvent displacement.

28. The process of claim 27, wherein the solvent displacement is performed using at least one of methanol, ethanol isopropanol, acetone, pentane and hexanes.

29. The process of any one of claims 1 to 26, wherein the purified conjugated polymer is isolated by concentrating the pregnant solution.

30. The process of any one of claims 1 to 29, further comprising a step of analyzing the purified conjugated polymer for any residual impurities.

31. The process of claim 30, wherein the analyzing comprises drying the purified conjugated polymer, thermally degrading the dried purified conjugated polymer and chemically digesting the thermally degraded conjugated polymer.

32. The process of claim 31 , wherein thermally degrading comprises heating the purified conjugated polymer to a temperature of at least 400°C.

33. The process of claim 31 , wherein the chemical digesting is performed using at least one of nitric and hydrochloric acid.

34. The process of claim 31 , wherein the chemical digesting is performed using a mixture of nitric and hydrochloric acid.

35. The process of claim 34, wherein the mixture comprises a molar ratio of about 1 :3 of nitric and hydrochloric acid.

36. The process of any one of claims 31 to 35, wherein the digested conjugated polymer is analyzed by inductively coupled plasma mass spectroscopy (ICP-MS).

37. The process of any one of claims 1 to 36, wherein the impurities are metal impurities.

38. A process for purifying a conjugated polymer, the process comprising: circulating a solution comprising a conjugated polymer through a column packed with an agent suitable for removing impurities from the conjugated polymer; and eluding a solution comprising a purified conjugated polymer from the column; wherein the agent is at least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, modified cellulose, and combinations of any thereof.

39. The process of claim 38, wherein the solution comprising the conjugated polymer is circulated through the agent-packed column in a closed-loop.

40. The process of claim 38 or 39, wherein the solution comprising the conjugated polymer has a temperature ranging from about -20°C to about 200°C.

41. The process of claim 40, wherein the solution comprising the conjugated polymer has a temperature ranging from about 20°C to about 180°C.

42. The process of claim 40 or 41 , wherein the solution comprising the conjugated polymer is subjected to a temperature gradient, wherein the temperature ranges from about 0°C to about 200°C.

43. The process of claim 42, wherein the temperature ranges from about 20°C to about 180°C.

44. The process of any one of claims 38 to 43, wherein the solution comprising the conjugated polymer is circulated through the agent-packed column over a period ranging from about 5 minutes to about 72 hours.

45. The process of any one of claims 38 to 44, wherein the solution comprising the conjugated polymer comprises at least one solvent selected from chlorobenzenes, xylenes, chloroform, acetone, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof.

46. The process of any one of claims 38 to 45, wherein the metal scavenger resin is at least one of a trimercaptotriazine and a sodium triaminetetraacetate functionalized resin.

47. The process of any one of claims 38 to 46, wherein the ion exchange resin is an acidic and / or basic ion exchange resin.

48. The process of claim 47, wherein the acidic ion exchange resin comprises Amberlyst® 15, Amberlyst® 36, AmberChrom® 50WX2, Dowex® 50WX4, Lewatit® TP 207 and Sephadex® C-50.

49. The process of claim 47, wherein the basic ion exchange resin comprises Amberlite® HPR4811 Cl, Amberlite® FPA66, AmberTec® UP550 OH, Diaion® WA30, Amberlyst® A26 and AmberChrom® 1X8.

50. The process of any one of claims 38 to 49, wherein the purified conjugated polymer is isolated by precipitation using solvent displacement.

51. The process of claim 50, wherein the solvent displacement is performed using at least one of methanol, ethanol, isopropanol, acetone, pentane and hexanes.

52. The process of any one of claims 38 to 49, wherein the purified conjugated polymer is isolated by concentrating the solution comprising the purified conjugated polymer.

53. The process of any one of claims 38 to 52, further comprising a step of analyzing the purified conjugated polymer for any residual impurities.

54. The process of claim 53, wherein the analyzing comprises drying the purified conjugated polymer, thermally degrading the dried purified conjugated polymer and chemically digesting the thermally degraded conjugated polymer.

55. The process of claim 54, wherein thermally degrading comprises heating the purified conjugated polymer to a temperature of at least 400°C.

56. The process of claim 54, wherein the chemical digesting is performed using at least one of nitric and hydrochloric acid.

57. The process of claim 54, wherein the chemical digesting is performed using a mixture of nitric and hydrochloric acid.

58. The process of claim 57, wherein the mixture comprises a molar ratio of about 1 :3 of nitric and hydrochloric acid.

59. The process of any one of claims 54 to 58, wherein the digested conjugated polymer is analyzed by inductively coupled plasma mass spectroscopy (ICP-MS).

60. The process of any one of claims 38 to 59, wherein the impurities are metal impurities.

61. A process for purifying a conjugated polymer, the process comprising: dissolving a conjugated polymer in a solvent to provide a solution; adding an agent to the solution to produce an impurity laden agent; removing the impurity laden agent from the solution to produce a pregnant solution comprising the purified conjugated polymer; and analyzing the purified conjugated polymer for any residual impurities. wherein the agent is at least one of a metal scavenger resin, an ion exchange resin, activated clay, charcoal, silica, alumina, diatomaceous earth, cellulose, modified cellulose, and combinations of any thereof.

62. The process of claim 61 , further comprising stirring the solution following the addition of the agent.

63. The process of claim 61 or 62, wherein the solution has a temperature ranging from about -20°C to about 200°C.

64. The process of claim 63, wherein the solution has a temperature ranging from about 20°C to about 180°C.

65. The process of claim 61 or 62, wherein the solution is subjected to a temperature gradient, wherein the temperature ranges from about 0°C to about 200°C.

66. The process of claim 65, wherein the temperature ranges from about 20°C to about 180°C.

67. The process of any one of claims 61 to 66, wherein the conjugated polymer is contacted with the agent for at least 30 seconds.

68. The process of claim 67, wherein the conjugated polymer is contacted with the agent for a period ranging from about 5 minutes to about 72 hours.

69. The process of any one of claims 61 to 68, wherein the solvent comprises at least one of chlorobenzenes, xylenes, chloroform, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof.

70. The process of any one of claims 61 to 69, wherein the metal scavenger resin is at least one of a trimercaptotriazine and a sodium triaminetetraacetate functionalized resin.

71. The process of any one of claims 61 to 70, wherein the ion exchange resin is an acidic and / or basic ion exchange resin.

72. The process of claim 71 , wherein the acidic ion exchange resin comprises Amberlyst® 15, Amberlyst® 36, AmberChrom® 50WX2, Dowex® 50WX4, Lewatit® TP 207 and Sephadex® C-50.

73. The process of claim 71 , wherein the basic ion exchange resin comprises Amberlite® HPR4811 Cl, Amberlite® FPA66, AmberTec® UP550 OH, Diaion® WA30, Amberlyst® A26 and AmberChrom® 1X8.

74. The process of any one of claims 61 to 73, wherein the mass ratio (w / w) of agent to conjugated polymer is at least 0.01 :1.0.

75. The process of any one of claims 61 to 73, wherein the mass ratio (w / w) of agent to conjugated polymer ranges from about 0.01 :1.0 to about 100.0:1.0.

76. The process of any one of claims 61 to 75, wherein the impurity laden agent is removed from the solution by filtration, decantation or centrifugation to produce an isolated impurity laden agent.

77. The process of claim 76, wherein the filtration is complemented by a filtration aid.

78. The process of claim 77, wherein the filtration aid is at least one of silica, alumina, diatomaceous earth, charcoal, sand, and combinations of any thereof.

79. The process of claim 78, wherein the filtration aid is Celite®.

80. The process of any one of claims 76 to 79, wherein the isolated impurity laden agent is extracted with a solvent to remove any unreacted agent.

81. The process of claim 80, wherein the extraction is performed once or multiple times.

82. The process of claim 80 or 81 , wherein the solvent is at least one of chlorobenzenes, xylenes, chloroform, acetone, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof.

83. The process of claim 81 , wherein the multiple extractions are performed using the same solvent or different solvents.

84. The process of claim 83, wherein the solvent or solvents are at least one of chlorobenzenes, xylenes, chloroform, acetone, hexanes, pentane, toluene, tetrahydrofuran, dioxane and combinations of any thereof.

85. The process of any one of claims 80 to 84, wherein the extraction is performed at temperatures ranging from about -20°C to about 200°C.

86. The process of claim 85, wherein the extraction is performed at temperatures ranging from about 20°C to about 180°C.

87. The process of any one of claims 61 to 86, wherein the purified conjugated polymer is isolated by precipitation using solvent displacement.

88. The process of claim 87, wherein the solvent displacement is performed using at least one of methanol, ethanol isopropanol, acetone, pentane and hexanes.

89. The process of any one of claims 61 to 86, wherein the purified conjugated polymer is isolated by concentrating the pregnant solution.

90. The process of claim 61 , wherein the analyzing comprises drying the purified conjugated polymer, thermally degrading the dried purified conjugated polymer and chemically digesting the thermally degraded conjugated polymer.

91. The process of claim 90, wherein thermally degrading comprises heating the purified conjugated polymer to a temperature of at least 400°C.

92. The process of claim 90, wherein the chemical digesting is performed using at least one of nitric and hydrochloric acid.

93. The process of claim 90, wherein the chemical digesting is performed using a mixture of nitric and hydrochloric acid.

94. The process of claim 93, wherein the mixture comprises a molar ratio of about 1 :3 of nitric and hydrochloric acid.

95. The process of any one of claims 90 to 94, wherein the digested conjugated polymer is analyzed by inductively coupled plasma mass spectroscopy (ICP-MS).

96. The process of any one of claims 61 to 95, wherein the impurities are metal impurities.

97. The process of any one of claims 1 to 96, wherein the purified conjugated polymer is for use in organic electronic applications and / or devices.

98. The process of claim 97, wherein the organic electronic applications and / or devices comprise organic solar cells (OPVs), organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs), sensors, photovoltaic cells, batteries, and / or capacitors.

99. A method for analyzing a conjugated polymer for impurities, the method comprising: drying the conjugated polymer to form a thin film; thermally degrading the dried purified conjugated polymer thin film; and chemically digesting the thermally degraded conjugated polymer.

100. The method of claim 99, wherein thermally degrading comprises heating the conjugated polymer to a temperature of at least 400°C.

101. The method of claim 99, wherein the chemical digesting is performed using at least one of nitric and hydrochloric acid.

102. The method of claim 99, wherein the chemical digesting is performed using a mixture of nitric and hydrochloric acid.

103. The method of claim 102, wherein the mixture comprises a molar ratio of about 1 :3 of nitric and hydrochloric acid.

104. The method of any one of claims 99 to 103, wherein the digested conjugated polymer is analyzed by inductively coupled plasma mass spectroscopy (ICP-MS).

105. The method of any one of claims 99 to 104, wherein the thin film has a thickness not exceeding 1 mm.

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