Title of Invention	"A PROCESS FOR THE PREPARATION OF POLYMERIC ADSORBENTS SELECTIVE FOR PHENOLIC COMPOUNDS"
Abstract	A process for the preparation of polymeric adsorbents which comprises polymerizing the template monomer having been adsorbed by known method along with cross linker and polymerization initiator, on the support polymer in a solvent by known method and the said template monomer being selected from carbonate ester or carboxylate ester having one or more vinylic /allylic/styrenic unsaturation on the macroporous support polymer being prepared by synthesizing with a high degree of crosslink density between 60 - 95% ;hydrolyzing the polymerized template monomer as obtained in step a) by acid or alkali treatment followed by washing with the solvent and drying to get the polymeric adsorbent.The polymeric adsorbents are selective for phenolic compounds.

Title of Invention

"A PROCESS FOR THE PREPARATION OF POLYMERIC ADSORBENTS SELECTIVE FOR PHENOLIC COMPOUNDS"

Abstract

A process for the preparation of polymeric adsorbents which comprises polymerizing the template monomer having been adsorbed by known method along with cross linker and polymerization initiator, on the support polymer in a solvent by known method and the said template monomer being selected from carbonate ester or carboxylate ester having one or more vinylic /allylic/styrenic unsaturation on the macroporous support polymer being prepared by synthesizing with a high degree of crosslink density between 60 - 95% ;hydrolyzing the polymerized template monomer as obtained in step a) by acid or alkali treatment followed by washing with the solvent and drying to get the polymeric adsorbent.The polymeric adsorbents are selective for phenolic compounds.

Full Text	This invention relates to a process for preparation of polymeric adsorbents. Phenolics are many times present in aromatic compounds as trace impurities e.g. phenol in anisole or nitrophenols in nitrobenzene, o,p -Bisphenol in bisphenol-A, p-tertiary butyl catechol in styrene). These impurities lead to problems in down stream processing of these chemicals. Aromatics containing phenolic impurities when undergo catalytic oxidation / reduction reactions phenols in them can form tarry products which poison / deactivate the catalyst. Hence for enhancing the catalyst life as well as for better economics of the process it is necessary to remove phenolic impurities from aromatics. Another necessity for removal of phenols arises from the improvement in quality which is desirable for any product. Phenolic impurities can be removed from aqueous streams using a variety of methods such as adsorption, distillation, and solvent extraction. These methods are commonly used on industrial scale as well. Various kinds of adsorbents are used to achieve the same goal. The adsorbents used for removal of phenolic compounds can be either inorganic or organic in nature. The inorganic adsorbents used for such applications are silica and zeolites where as commonly used organic adsorbents are polymeric in nature. There are two kinds of polymeric adsorbents in common use for removal of phenolic compounds. These are crosslinked styrene - divinylbenzene resins (Amberlite XAD - 2, 4) marketed by Rohm and Haas or their equivalems and crosslinked acrylate / methacrylate resins ( Amberlite XAD - 7, 8 ) or their equivalents. These are suitable for removal of phenolic compounds from aqueous phase. Though these adsorbents are suitable for removal of phenolic compounds from aqueous phase, they do not have any structural feature which can distinguish between various phenols and hence they are not selective for a particular phenol. These adsorbents are able to remove phenolic compounds from aqueous streams as well as non polar organic streams mainly based on the polarity difference between the solute and the solvent. In literature there are references for preparation of polymers which are selective to a particular substrate such as drug molecules (theophyllin, phenobarbital, creatanine), sterols (cholesterol, corticosteroids), nucleic acid bases, carbohydrates etc. The technique of preparation of such polymers is known as molecular imprinting ( Wnlff, G., Angew. Chem. Int. Ed, Eng., 34 (1995 ), 1812 -1832, Mosbach, K. mid Ramstrom, 0., Biotechnology, 14 (1996), 163 - 173, Steinke, J., Sherringtw, D. C. and Dunkin, I. R., Advances in polymer science Vol. 123 (1995 ), 81 -125). The polymers prepared by this technique are known as molecularly imprinted polymers or more commonly and herein after referred as MIPs. (MIPs) The MIPs are prepared by polymerization of monomers around a template molecule in the presence of a large excess of crosslinks. The template is either covalently or non covalently linked to the monomers. After the polymerization the template is removed from the polymer leaving behind a cavity in the polymer. These cavities have shape and size similar to the template molecule used during polymerization and hence are selective to those particular substrates. There are no reports in the literature for the preparatic polymeric adsorbents selective for phenolic compounds using molecular imprinting teacque. The object of the present invention is therefore to provide a process for the preparation of polymeric adsorbents. Accordingly the present invention provides a process for the preparation of polymeric adsorbents selected phenelie compound for which comprises: a) polymerizing the template monomer having been adsorbed by known method along with cross linker and polymerization initiatorf on the support polymerlin a solvent by known method and the said template monomer being selected from carbonate ester or carboxylate ester having one or more vinylic /allylic/styrenic unsaturation on the macroporous support polymer being prepared by synthesizing with a high degree of crosslink density between 60 - 95% as here in described by known methods; b) hydrolyzing the polymerized template monomer as obtained in step a) by acid or alkali treatment followed by washing with the solvent and drying to get the polymeric adsorbent. In an embodiment the monomers used for preparation of the support polymer may be preferably acrylic or methacrylic or styrenic and / or their mixture, wherein one of the monomers has two or more unsaturations, as exemplified as glycidyl methacrylate, ethylene glycol dimethacrylate, trimethylol propane trimethacrylate, styrene, divinyl benzene , trimethylol propane triacrylate, ethylene glycol diacrylate. In another embodiment the crosslink density of the support polymer used may be between 60 to 35 % and more preferably ≥80 %. In another embodiment the support polymer may have a particle size ranging between 25 to 250 p., preferably between 25 to 100 µ and most preferably between 37 to 75 n. In another embodiment the solvent used for suspending the support polymer may be preferably an aromatic solvent such as benzene, toluene, xylene. In yet another embodiment the template monomer may be either a carbonate ester or carboxylate ester having one or more vinylic / allylic / styrenic unsaturations as exemplified by 2 - methacryloyl, ethyl, phenyl carbonate, Phenyl, 4 - vinyl benzoate, phenyl, 4 - vinyl phenyl carbonate, p- nitrophenyl methacrylate, allyl, 2,4- DHB (2,4-dihydroxy benzophenone) carbonate, phenyl acrylate, phenyl methacrylate p- cumyl phenyl methacrylate, allyl, bisphenyl carbonate, 2,4- DHB methacrylate, allyl, 2,4-dinitrophenyl carbonate, 2,4- dinitrophenyl methacrylate, p- methoxy phenyl methacrylate, o- methoxy phenyl methacrylate, allyl, p- methoxy phenyl carbonate, allyl, o- methoxy phenyl carbonate, p-methoxy phenyl acrylate, o- methoxy phenyl acrylate. In yet another embodiment the initiator used for the thermal polymerization may be chosen from a class of compounds such as azo, peroxides, hydroperoxides, persulphates, preferably from azo initiators. In yet another embodiment the crosslinker may be of acrylic / methacrylic or styrenic in nature or comprise of mixture of these and have two or more unsaturations such as ethylene glycol dimethacrylate, ethylene glycol diacrylate, trimethylol propane triacrylate, trimethylol propane trimethacrylate, divinyl benzene. In yet another embodiment the polymerization of the template monomer may be preferentially carried out thermally between 60 - 90 °C and more preferably between 70 -80 oC. In yet another embodiment the hydrolysis of the template monomer may be carried out using preferably alkali solution viz. NaOH or KOH of a strength between 0.1 to 2.0 N and more preferably between 0.5 to 1.5 N for a period in the range of 6 to 10 hours. In yet another embodiment the solvents used for washing of the polymer may be such as ethanol, methanol, acetone, chloroform, preferably methanol. In a feature of the present invention provides a process for preparation of polymeric adsorbents which comprises of synthesizing a macroporous support polymer. These are synthesized using standard polymerization techniques such as suspension, emulsion or dispersion polymerization etc (Svec, F., Hrdil, ./., Conpec, ./. and Kalal, J., Angew. MakromoL Chem., 48(1975), 135-143, Reddy, K. S., Ganr, P. M., Anand, P. S. and Dasare, B. D., J. Polymer. Materials, 6 (1989), 257 - 262, Okey. 0. and Gimin, C, J. Appl. Polym. Sci., 46 ( 1992 ), 401 - 410. ). The polymers synthesized by the techniques mentioned above are porous in nature with a Urge surface area and find diverse applications such as chromatographic supports, supports for catalyst immobilization, ion exchangers as well as adsorbents. The process of the present invention is described heroin below with reference to the examples which are illustrative only and should not be construed to limit the scope of the present invention in any manner. Example 1 To a well stirred solution of poly vinylpyrrolidone, (PVP), molecular weight 360,000 containing 3.0 g PVP and 0.3 g sodium lauryl sulphate (SLS) in 300 ml distilled water a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 10.88 g glycidyl methacrylate ( GMA ), 16.32 g ethylene glycol dimcthacrylate ( EGDMA ) and 0.272 g azobis isobutyronitrile ( AEBN ) was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 37 - 75 µ was chosen for synthesis of ATPs. 1.0 g of above polymer was dispersed in about 100 ml benzene and to the suspension 0.4 g phenyl, 4 -vinyl benzoate, 200 µ1 EGDMA and 50 mg AIBN were added to it. The suspension was stirred till the solvent evapomtes and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 50 ml of 2 N NaOH for 6 hours, washed with water, dil: HC1, methanol and finally dried. Example 2 To a well stirred solution of PVP, molecular wt. 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water, a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 2.72 g GMA, 24.48 g EGDMA and 0.272 g of AIBN was added slowly. The suspension formed'was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction .between 37 - 75 µ was chosen for synthesis of MIPs. 1.0 g of above polymer was dispersed in about 100 ml benzene and to the suspension 0.4 g 2 - methacryloyl ethyl, phenyl carbonate, 200 µl EGDMA and 50 mg ATBN were added. The suspension was stirred till the solvent evaporates 2nd the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 50 ml of 2 N NaOH for 6 hours, washed with water, methanol and finally dried. Example 3 To a well stirred solution of PVP, molecular wt. 360,000 containing 1.2 g PVP and 0.12 g SLS in 120 ml distilled water, a solution of 19.5 g cyclohexanol and 2.17 g dodecanol containing 1.64 g of GMA, 14.7 g of trimethylol propane trimethacrylate ( TRIM ) and 0.163 g of AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 30 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum-oven at 50 °C. The microspheres were sieved and the fraction between 45 - 75 µ, was chosen for synthesis of MIPs. 1.0 g of above polymer was dispersed in about 100 ml benzene and to the suspension 0.4 g phenyl, 4 - vinyl phenyl carbonate, 200 nl EGDMA and 50 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 50 ml of 1 N NaOH for 6 hours, washed with water, methanol and finally dried. EXAMPLE 4 To a well stirred solution of PVP, molecular weight 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 10.88 g GMA, 16.32 g EGDMA and 0.272 g AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 37 - 75 µ was chosen for synthesis of MIPs. 1.0 g of above polymer was dispersed in about 50 ml benzene and to the suspension 0.3 g phenyl itaconate, 100µ1 EGDMA and 25 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 50 ml of 2N NaOH for 6 hours, washed with water, methanol ami finally dried. EXAMPLE 5 To a well stirred solution of, PVP, molecular weight 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 10.88 g GMA, 16.32 g EGDMA and 0.272 g A[BN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 37 - 75 µ was chosen for synthesis of MEPs. 0.75 g of above polymer was dispersed in about 75 ml benzene and to the suspension 0.3 g 4'- nitrophenyl, 4- vinyl benzoate, 75 µl EGDMA and 25 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 50 ml of 2N NaOH for 6 hours, washed with water, methanol and finally dried. EXAMPLE 6 To a well stirred solution of PVP, molecular weight 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 10.88 g GMA , 16.32 g EGDMA and 0.272 g AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 37 - 75µwas chosen for synthesis,of MlPs. 2.0 g of above - polymer was dispersed in about 75 ml benzene and to the suspension 0.8 g allyl, p- nitrophenyl carbonate, 400 µl EGDMA and 50 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 100 ml of 2N NaOH for 6 hours, washed with water, methanol and finally dried. EXAMPLE 7 To a well stirred solution of PVP, molecular weight 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 10.88 g GMA, 16.32 g EGDMA and 0.272 g AIBN) was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 37 - 75 µ was chosen for synthesis of MIPs. 3.0 g of above polymer was dispersed in about 100 ml benzene and to the suspension 1.2 g p- tertiary butyl catecholyl dimethacrylate, 600µl EGDMA and 75 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 100 ml of 2N NaOH for 6 hours, washed with water, methanol, and finally dried. EXAMPLE 8 To a well stirred solution of PVP, molecular weight 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 10.88 g GMA, 16.32 g EGDMA and 0.272 g AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 37 - 75 µ was chosen for synthesis of MIPs. 3.0 g of above polymer was dispersed in about 50 ml benzene and to the suspension 1.2 g allyl PTBC (p- tertiary butyl catechol) carbonate, 600 µ EGDMA and 75 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 100 ml of 2N NaOH for 6 hours, washed with water, methanol and finally dried. EXAMPLE 9 To a well stirred solution of PVP, molecular wt. 360,000 containing 1.2 g PVP and 0.12 g SLS in 120 ml distilled water, a solution of 19.5 g cyclohexanol and 2,17 g dodecanol containing 1.64 g of GMA, 14.7 g of TRIM and 0.163 g of AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheros were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 45 - 75 µ was chosen for synthesis of MIPs. 2.0 g of above polymer was dispersed in about 50 ml benzene and to the suspension 0.8 g of phenyl methacrylate, 400 µl EGDMA and 50 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 100 ml of IN NaOH for 6 hours, washed .with water, methanol and finally dried. EXAMPLE 10 To a well stirred solution of PVP, molecular wt. 360,000 containing 1.2 g PVP and 0.12 g SLS in 120 ml distilled water, a solution of 19.5 g cyclohexanol and 2.17 g dodecanol containing 1.64 g of GMA, 14.7 g of TRIM and 0.163 g of AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 45 - 75µ was chosen for synthesis of MIPs. 2.0 g of above polymer was dispersed in about 50 ml benzene and to the suspension 0.8 g of allyl bisphenyl carbonate, 400 µl EGDMA and 50 mg AJBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with mtethanol and dried. The template was then hydrolyzed by refluxing the ipolymer with 100 ml of IN NaOH for 6 hours, washed with water, methanol and finally dried. EXAMPLE 11 To a well stirred solution of PVP, molecular wt. 360,000 containing 1.2 g PVP and 0.12 g SLS in 120 ml distilled water, a solution of 19.5 g cyclohexanol and 2.17 g dodecanol containing 1.64 g of GMA, 14.7 g of TRIM and 0.163 g of AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 45 - 75µ was chosen for synthesis of MTPs. 2.0 g of above polymer was dispersed in about 75 ml benzene and to the suspension 0.8 g of p- cumyl, phenyl methacrylate, 400 µl EGDMA and 50 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrofyzed by refluxing the polymer with 100 ml of 1N NaOH for 6 hours, washed with water, methanol and finally dried. EXAMPLE 12 To a well stirred solution of PVP, molecular wt. 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water, a solution of 36.76 g cyclohexanol and 4.08 g doctecanol containing 2.72 g GMA, 24.48 g EGDMA and 0.272 g of AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol, and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 37 - 75 u. was chosen for synthesis of MIPs. 4.0 g of above polymer was dispersed in about 100 ml benzene and to the suspension 0.8 g of 2,4- DHB methacrylate, 800 µl EGDMA and 100 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 100 ml of 1N NaOH for 6 hours, washed with water, methanol and finally dried. The process of the above invention has following advantages 1. The process provides means for preparation of polymeric adsorbents which are selective for phenolic compounds. 2. The process being generic in nature can be extended to synthesis of MIPs selective for various other substrates of importance. 3. This process can also be carried out on various macroporous inorganic supports.

Full Text

This invention relates to a process for preparation of polymeric adsorbents.
Phenolics are many times present in aromatic compounds as trace impurities e.g. phenol in anisole or nitrophenols in nitrobenzene, o,p -Bisphenol in bisphenol-A, p-tertiary butyl catechol in styrene). These impurities lead to problems in down stream processing of these chemicals. Aromatics containing phenolic impurities when undergo catalytic oxidation / reduction reactions phenols in them can form tarry products which poison / deactivate the catalyst. Hence for enhancing the catalyst life as well as for better economics of the process it is necessary to remove phenolic impurities from aromatics. Another necessity for removal of phenols arises from the improvement in quality which is desirable for any product.
Phenolic impurities can be removed from aqueous streams using a variety of methods such as adsorption, distillation, and solvent extraction. These methods are commonly used on industrial scale as well.
Various kinds of adsorbents are used to achieve the same goal. The adsorbents used for removal of phenolic compounds can be either inorganic or organic in nature. The inorganic adsorbents used for such applications are silica and zeolites where as commonly used organic adsorbents are polymeric in nature.
There are two kinds of polymeric adsorbents in common use for removal of phenolic compounds. These are crosslinked styrene - divinylbenzene resins (Amberlite XAD - 2, 4) marketed by Rohm and Haas or their equivalems and crosslinked acrylate /

methacrylate resins ( Amberlite XAD - 7, 8 ) or their equivalents. These are suitable for removal of phenolic compounds from aqueous phase.
Though these adsorbents are suitable for removal of phenolic compounds from aqueous phase, they do not have any structural feature which can distinguish between various phenols and hence they are not selective for a particular phenol. These adsorbents are able to remove phenolic compounds from aqueous streams as well as non polar organic streams mainly based on the polarity difference between the solute and the solvent.
In literature there are references for preparation of polymers which are selective to a particular substrate such as drug molecules (theophyllin, phenobarbital, creatanine), sterols (cholesterol, corticosteroids), nucleic acid bases, carbohydrates etc. The technique of preparation of such polymers is known as molecular imprinting ( Wnlff, G., Angew. Chem. Int. Ed, Eng., 34 (1995 ), 1812 -1832, Mosbach, K. mid Ramstrom, 0., Biotechnology, 14 (1996), 163 - 173, Steinke, J., Sherringtw, D. C. and Dunkin, I. R., Advances in polymer science Vol. 123 (1995 ), 81 -125). The polymers prepared by this technique are known as molecularly imprinted polymers or more commonly and herein after referred as MIPs. (MIPs)
The MIPs are prepared by polymerization of monomers around a template molecule in the presence of a large excess of crosslinks. The template is either covalently or non covalently linked to the monomers. After the polymerization the template is removed from the polymer leaving behind a cavity in the polymer. These cavities have shape and size similar to the template molecule used during polymerization and hence are selective to those particular substrates.

There are no reports in the literature for the preparatic polymeric adsorbents selective for phenolic compounds using molecular imprinting teacque.
The object of the present invention is therefore to provide a process for the preparation of polymeric adsorbents.
Accordingly the present invention provides a process for the preparation of polymeric adsorbents selected phenelie compound for which comprises:
a) polymerizing the template monomer having been adsorbed by known
method along with cross linker and polymerization initiatorf on the support
polymerlin a solvent by known method and the said template monomer
being selected from carbonate ester or carboxylate ester having one or more
vinylic /allylic/styrenic unsaturation on the macroporous support polymer
being prepared by synthesizing with a high degree of crosslink density
between 60 - 95% as here in described by known methods;
b) hydrolyzing the polymerized template monomer as obtained in step a) by
acid or alkali treatment followed by washing with the solvent and drying to
get the polymeric adsorbent.
In an embodiment the monomers used for preparation of the support polymer may be preferably acrylic or methacrylic or styrenic and / or their mixture, wherein one of the monomers has two or more unsaturations, as exemplified as glycidyl methacrylate, ethylene glycol dimethacrylate, trimethylol propane trimethacrylate, styrene, divinyl benzene , trimethylol propane triacrylate, ethylene glycol diacrylate.

In another embodiment the crosslink density of the support polymer used may be between 60 to 35 % and more preferably ≥80 %.
In another embodiment the support polymer may have a particle size ranging between 25 to 250 p., preferably between 25 to 100 µ and most preferably between 37 to 75 n.
In another embodiment the solvent used for suspending the support polymer may be preferably an aromatic solvent such as benzene, toluene, xylene.
In yet another embodiment the template monomer may be either a carbonate ester or carboxylate ester having one or more vinylic / allylic / styrenic unsaturations as exemplified by 2 - methacryloyl, ethyl, phenyl carbonate, Phenyl, 4 - vinyl benzoate, phenyl, 4 - vinyl phenyl carbonate, p- nitrophenyl methacrylate, allyl, 2,4- DHB (2,4-dihydroxy benzophenone) carbonate, phenyl acrylate, phenyl methacrylate p- cumyl phenyl methacrylate, allyl, bisphenyl carbonate, 2,4- DHB methacrylate, allyl, 2,4-dinitrophenyl carbonate, 2,4- dinitrophenyl methacrylate, p- methoxy phenyl methacrylate, o- methoxy phenyl methacrylate, allyl, p- methoxy phenyl carbonate, allyl, o- methoxy phenyl carbonate, p-methoxy phenyl acrylate, o- methoxy phenyl acrylate.
In yet another embodiment the initiator used for the thermal polymerization may be chosen from a class of compounds such as azo, peroxides, hydroperoxides, persulphates, preferably from azo initiators.
In yet another embodiment the crosslinker may be of acrylic / methacrylic or styrenic in nature or comprise of mixture of these and have two or more unsaturations such as ethylene glycol dimethacrylate, ethylene glycol diacrylate, trimethylol propane triacrylate, trimethylol propane trimethacrylate, divinyl benzene.

In yet another embodiment the polymerization of the template monomer may be preferentially carried out thermally between 60 - 90 °C and more preferably between 70 -80 oC.
In yet another embodiment the hydrolysis of the template monomer may be carried out using preferably alkali solution viz. NaOH or KOH of a strength between 0.1 to 2.0 N and more preferably between 0.5 to 1.5 N for a period in the range of 6 to 10 hours.
In yet another embodiment the solvents used for washing of the polymer may be such as ethanol, methanol, acetone, chloroform, preferably methanol.
In a feature of the present invention provides a process for preparation of polymeric adsorbents which comprises of synthesizing a macroporous support polymer. These are synthesized using standard polymerization techniques such as suspension, emulsion or dispersion polymerization etc (Svec, F., Hrdil, ./., Conpec, ./. and Kalal, J., Angew. MakromoL Chem., 48(1975), 135-143, Reddy, K. S., Ganr, P. M., Anand, P. S. and Dasare, B. D., J. Polymer. Materials, 6 (1989), 257 - 262, Okey. 0. and Gimin, C, J. Appl. Polym. Sci., 46 ( 1992 ), 401 - 410. ). The polymers synthesized by the techniques mentioned above are porous in nature with a Urge surface area and find diverse applications such as chromatographic supports, supports for catalyst immobilization, ion exchangers as well as adsorbents.
The process of the present invention is described heroin below with reference to the examples which are illustrative only and should not be construed to limit the scope of the present invention in any manner.

Example 1
To a well stirred solution of poly vinylpyrrolidone, (PVP), molecular weight 360,000 containing 3.0 g PVP and 0.3 g sodium lauryl sulphate (SLS) in 300 ml distilled water a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 10.88 g glycidyl methacrylate ( GMA ), 16.32 g ethylene glycol dimcthacrylate ( EGDMA ) and 0.272 g azobis isobutyronitrile ( AEBN ) was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 37 - 75 µ was chosen for synthesis of ATPs.
1.0 g of above polymer was dispersed in about 100 ml benzene and to the suspension 0.4 g phenyl, 4 -vinyl benzoate, 200 µ1 EGDMA and 50 mg AIBN were added to it. The suspension was stirred till the solvent evapomtes and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 50 ml of 2 N NaOH for 6 hours, washed with water, dil: HC1, methanol and finally dried.
Example 2
To a well stirred solution of PVP, molecular wt. 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water, a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 2.72 g GMA, 24.48 g EGDMA and 0.272 g of AIBN was added slowly. The suspension formed'was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the

polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction .between 37 - 75 µ was chosen for synthesis of MIPs.
1.0 g of above polymer was dispersed in about 100 ml benzene and to the suspension 0.4 g 2 - methacryloyl ethyl, phenyl carbonate, 200 µl EGDMA and 50 mg ATBN were added. The suspension was stirred till the solvent evaporates 2nd the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 50 ml of 2 N NaOH for 6 hours, washed with water, methanol and finally dried.
Example 3
To a well stirred solution of PVP, molecular wt. 360,000 containing 1.2 g PVP and 0.12 g SLS in 120 ml distilled water, a solution of 19.5 g cyclohexanol and 2.17 g dodecanol containing 1.64 g of GMA, 14.7 g of trimethylol propane trimethacrylate ( TRIM ) and 0.163 g of AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 30 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum-oven at 50 °C. The microspheres were sieved and the fraction between 45 - 75 µ, was chosen for synthesis of MIPs.
1.0 g of above polymer was dispersed in about 100 ml benzene and to the suspension 0.4 g phenyl, 4 - vinyl phenyl carbonate, 200 nl EGDMA and 50 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was

washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 50 ml of 1 N NaOH for 6 hours, washed with water, methanol and finally dried.
EXAMPLE 4
To a well stirred solution of PVP, molecular weight 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 10.88 g GMA, 16.32 g EGDMA and 0.272 g AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 37 - 75 µ was chosen for synthesis of MIPs.
1.0 g of above polymer was dispersed in about 50 ml benzene and to the suspension 0.3 g phenyl itaconate, 100µ1 EGDMA and 25 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 50 ml of 2N NaOH for 6 hours, washed with water, methanol ami finally dried.

EXAMPLE 5
To a well stirred solution of, PVP, molecular weight 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 10.88 g GMA, 16.32 g EGDMA and 0.272 g A[BN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 37 - 75 µ was chosen for synthesis of MEPs.
0.75 g of above polymer was dispersed in about 75 ml benzene and to the suspension 0.3 g 4'- nitrophenyl, 4- vinyl benzoate, 75 µl EGDMA and 25 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 50 ml of 2N NaOH for 6 hours, washed with water, methanol and finally dried.
EXAMPLE 6
To a well stirred solution of PVP, molecular weight 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 10.88 g GMA , 16.32 g EGDMA and 0.272 g AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven

at 50 °C. The microspheres were sieved and the fraction between 37 - 75µwas chosen for synthesis,of MlPs.
2.0 g of above - polymer was dispersed in about 75 ml benzene and to the suspension 0.8 g allyl, p- nitrophenyl carbonate, 400 µl EGDMA and 50 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 100 ml of 2N NaOH for 6 hours, washed with water, methanol and finally dried.
EXAMPLE 7
To a well stirred solution of PVP, molecular weight 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 10.88 g GMA, 16.32 g EGDMA and 0.272 g AIBN) was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 37 - 75 µ was chosen for synthesis of MIPs.
3.0 g of above polymer was dispersed in about 100 ml benzene and to the suspension 1.2 g p- tertiary butyl catecholyl dimethacrylate, 600µl EGDMA and 75 mg
AIBN were added . The suspension was stirred till the solvent evaporates and the dry
powder was polymerized thermally at 75 °C for 24 hours. After polymerization the
product was washed with methanol and dried. The template was then hydrolyzed by

refluxing the polymer with 100 ml of 2N NaOH for 6 hours, washed with water, methanol, and finally dried.
EXAMPLE 8
To a well stirred solution of PVP, molecular weight 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water a solution of 36.76 g cyclohexanol and 4.08 g dodecanol containing 10.88 g GMA, 16.32 g EGDMA and 0.272 g AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 37 - 75 µ was chosen for synthesis of MIPs.
3.0 g of above polymer was dispersed in about 50 ml benzene and to the suspension 1.2 g allyl PTBC (p- tertiary butyl catechol) carbonate, 600 µ EGDMA and 75 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 100 ml of 2N NaOH for 6 hours, washed with water, methanol and finally dried.
EXAMPLE 9
To a well stirred solution of PVP, molecular wt. 360,000 containing 1.2 g PVP and 0.12 g SLS in 120 ml distilled water, a solution of 19.5 g cyclohexanol and 2,17 g dodecanol containing 1.64 g of GMA, 14.7 g of TRIM and 0.163 g of AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was

maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheros were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 45 - 75 µ was chosen for synthesis of MIPs.
2.0 g of above polymer was dispersed in about 50 ml benzene and to the suspension 0.8 g of phenyl methacrylate, 400 µl EGDMA and 50 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 100 ml of IN NaOH for 6 hours, washed .with water, methanol and finally dried.
EXAMPLE 10
To a well stirred solution of PVP, molecular wt. 360,000 containing 1.2 g PVP and 0.12 g SLS in 120 ml distilled water, a solution of 19.5 g cyclohexanol and 2.17 g dodecanol containing 1.64 g of GMA, 14.7 g of TRIM and 0.163 g of AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 45 - 75µ was chosen for synthesis of MIPs.
2.0 g of above polymer was dispersed in about 50 ml benzene and to the suspension 0.8 g of allyl bisphenyl carbonate, 400 µl EGDMA and 50 mg AJBN were added . The suspension was stirred till the solvent evaporates and the dry powder was

polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with mtethanol and dried. The template was then hydrolyzed by refluxing the
ipolymer with 100 ml of IN NaOH for 6 hours, washed with water, methanol and finally dried.
EXAMPLE 11
To a well stirred solution of PVP, molecular wt. 360,000 containing 1.2 g PVP and 0.12 g SLS in 120 ml distilled water, a solution of 19.5 g cyclohexanol and 2.17 g dodecanol containing 1.64 g of GMA, 14.7 g of TRIM and 0.163 g of AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 45 - 75µ was chosen for synthesis of MTPs.
2.0 g of above polymer was dispersed in about 75 ml benzene and to the suspension 0.8 g of p- cumyl, phenyl methacrylate, 400 µl EGDMA and 50 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrofyzed by refluxing the polymer with 100 ml of 1N NaOH for 6 hours, washed with water, methanol and finally dried.
EXAMPLE 12
To a well stirred solution of PVP, molecular wt. 360,000 containing 3.0 g PVP and 0.3 g SLS in 300 ml distilled water, a solution of 36.76 g cyclohexanol and 4.08 g

doctecanol containing 2.72 g GMA, 24.48 g EGDMA and 0.272 g of AIBN was added slowly. The suspension formed was stirred at 500 RPM for 8 hours. Temperature was maintained at 70 °C for 2 hours and 80 °C for 6 hours. After the polymerization the polymeric microspheres were washed with water and methanol, and dried in vacuum oven at 50 °C. The microspheres were sieved and the fraction between 37 - 75 u. was chosen for synthesis of MIPs.
4.0 g of above polymer was dispersed in about 100 ml benzene and to the suspension 0.8 g of 2,4- DHB methacrylate, 800 µl EGDMA and 100 mg AIBN were added . The suspension was stirred till the solvent evaporates and the dry powder was polymerized thermally at 75 °C for 24 hours. After polymerization the product was washed with methanol and dried. The template was then hydrolyzed by refluxing the polymer with 100 ml of 1N NaOH for 6 hours, washed with water, methanol and finally dried.
The process of the above invention has following advantages
1. The process provides means for preparation of polymeric adsorbents which are
selective for phenolic compounds.
2. The process being generic in nature can be extended to synthesis of MIPs
selective for various other substrates of importance.
3. This process can also be carried out on various macroporous inorganic supports.

Documents:

2620-del-1998-abstract.pdf

2620-del-1998-correspondence-others.pdf

2620-del-1998-correspondence-po.pdf

2620-del-1998-description (complete).pdf

2620-del-1998-form-1.pdf

2620-del-1998-form-19.pdf

2620-del-1998-form-2.pdf

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Patent Number

217331

Indian Patent Application Number

2620/DEL/1998

PG Journal Number

15/2008

Publication Date

11-Apr-2008

Grant Date

26-Mar-2008

Date of Filing

03-Sep-1998

Name of Patentee

COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH

Applicant Address

RAFI MARG, NEW DELHI-110 001, INDIA.

Inventors:

#	Inventor's Name	Inventor's Address
1	VIVEK PRABHAKAR JOSHI	NATIONAL CHEMICAL LABORATORY, PUNE 411008, INDIA.
2	MOHAN GOPALKISHNA KULKARNI	NATIONAL CHEMICAL LABORATORY, PUNE 411008, INDIA.
3	RAGHUNATHANANT MASHELKAR	NATIONAL CHEMICAL LABORATORY, PUNE 411008, INDIA.

PCT International Classification Number

C08F 255/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA