Title of Invention: METHOD FOR PREPARATION OF HIGH

POLARITY CROSSLINKABLE POLYMER

Technical Field

Technical Field

[1] The present invention relates to a method for preparation of high polarity

crosslinkable polymer, high polarity crosslinkable polymer and its uses for chemical sensing application.

Background Art

Background Art

[2] US7432326 disclosed an acrylate-based pressure-sensitive adhesive comprising a polymer blend having (a) at least a first component Kc which comprises a first acrylate block copolymer having at least two chemically distinguishable, covalently interlinked acrylate polymer blocks P, the at least two polymer blocks P independently of one another each being a homopolymer block of a first monomer or a copolymer block of a second monomer and a comonomer, and the first monomer of the homopolymer block and the second monomer of the copolymer block can be identical or different from one another, and the at least two polymer blocks P being present under application conditions in microphase-separated regions and each having a softening temperature of between -125 and +20°C, and (b) at least one second component L _D , which is a second acrylate block copolymer, distinguishable from component Kc, having at least two chemically distinguishable, covalently interlinked acrylate polymer blocks P, with the features specified under (a), or is an acrylate polymer P _s , which is a homopolymer of a first monomer or a copolymer of a second monomer and a comonomer, the acrylate polymer P _s and the acrylate polymer blocks P having softening temperatures of between -125 and +20°C.

[3] US 7,211,625 disclosed a thermoplastic resin composition which is excellent in oil resistance, heat resistance, weatherability, impact resistance, transparency, and moldability, and which can be produced economically, an elastomer composition with low hardness and high tensile strength which is excellent in oil resistance and compression set, and a molded object produced by molding the thermoplastic resin composition or elastomer composition. The composition is produced by compounding a thermoplastic resin or an elastomer with a block copolymer having at least one methacrylic ester polymer block and at least one acrylic ester polymer block. Also provided are a process for producing a methacrylic ester-acrylic ester-methacrylic ester block copolymer which requires hardly any purification, which is excellent in heat re- sistance and weatherability, and in which the molecular weight and the molecular- weight distribution are controlled, and a methacrylic ester-acrylic ester-methacrylic ester block copolymer produced by the process.

[4] Prior arts problems, the US 7432326 acrylate-based pressure-sensitive adhesive is not suitable as heat curable low impedance matrix for chemical sensing application.

Whereas, the polymer blends in US 7,211,625 exhibits high impedance characteristics that is also less suitable for chemical sensing application.

[5] Hence, there is still a need in the art for a method for preparation of high polarity crosslinkable polymer and high polarity crosslinkable polymer having improved properties and its uses for chemical sensing application.

Disclosure of Invention

Technical Problem

[6]

Technical Solution

[7]

Summary

[8] According to a first aspect of the invention, there is provided a method of preparing high polarity crosslink-able co-polymer comprises the steps of:

[9] a. purifying the methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by washing with saturated sodium bicarbonate solution, drying with sodium sulfate, magnesium sulfate and stirring over barium oxide or phosphorus pentoxide or calcium hydride followed by distillation at atmopheric pressure or under reduced pressure;

[10] b. mixing appropriate ratios of methyl methacrylate, glycidyl methacrylate and

tetrahydrofurfuryl acrylate monomers;

[11] c. adding 1 to 5 parts of benzene or toluene solvent to the total volume of the methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers;

[12] d. adding 3mg to 0.3g of benzoyl peroxide catalyst to the reaction mixture;

[13] e. refluxing the reaction mixture at 80 to 100°C for 2 to 20 hours under blanket of argon or purified nitrogen gas; and

[14] f. decanting the remaining benzene or toluene solvent, washing the crosslink-able MGT co-polymer with petroleum ether.

[15] According to a second aspect of the present invention, there is provided a crosslink- able high polarity MGT co-polymer as the product of the above method characterized in that the ratio of methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by volume is 7:2:1.

[16] According to a third aspect of the present invention, there is provided crosslink-able high polarity MGT co-polymer as the product of the above method, characterized in that the ratio of methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by volume is 6:2:2.

[17] According to a fourth aspect of the present invention, there is provided a crosslink- able high polarity MGT co-polymer as product of the above method, characterized in that the ratio of methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by volume is 5:3:2.

[18] According to a fifth aspect of the present invention, there is provided a crosslink-able high polarity MGT co-polymer as product of the above method, characterized in that the ratio of methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by volume is 4:3:3.

[19] According to a sixth aspect of the present invention, there is provided a crosslink- able high polarity MGT co-polymer as product of the above method characterized in that the ratio of methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by volume is 3:4:3.

[20] According to a seventh aspect of the present invention, there is provided a crosslink- able high polarity MGT co-polymer as product of the above method, characterized in that the ratio of methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by volume is 3:3:4.

[21] According to eight aspect of the present invention, there is provided a use of the MGT high polarity crosslink-able co-polymer product of the above method for the manufacture of solid-state sensing electrodes as thermoset binder.

[22] Advantageously, the method of preparing high polarity crosslink-able co-polymer is economical due to viability of the precursors and availability of low cost and high purity monomers.

[23] Advantageously, the method preparation of crosslink-able high polarity polymeric membrane shows good characteristics as heat curable binder for fabrication of mem- braneless bio-chemical sensing electrodes for continuous environmental monitoring.

[24] Advantageously, the physical characteristic of the monomers which are high vapour pressure, low toxicity contributed to ease of handling of the monomers.

[25] Advantageously, the method is simple and no further purification required for the copolymer products.

Description of Drawings

[26] Figure 1 : illustrates structure of cross-linkable high polarity methyl methacrylate- glycidyl methacrylate-tetrahydrofurfuryl acrylate (MGT) co-polymer unit.

[27] Figure 2 : illustrates structures of methyl methacrylate (1), glycidyl methacrylate (2) and tetrahydrofurfuryl acrylate (3) monomers.

[28] Figure 3 : illustrates methyl methacrylate, glycidyl methacrylate and tetrahydro- furfuryl acrylate copolymer (4).

[29] Figure 4 : . illustrates photo of MGT 622 copolymer.

[30] Figure 5 : . illustrates photo of MGT 532 copolymer.

[31]

[32] Detailed description of the present invention

[33] The invention is herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention.

[34] The present invention provides a method of preparing high polarity crosslink-able co-polymer comprises the steps of: a) purifying the methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by washing with saturated sodium bicarbonate solution, drying with sodium sulfate, magnesium sulfate and stirring over barium oxide or phosphorus pentoxide or calcium hydride followed by distillation at atmopheric pressure or under reduced pressure; b) mixing appropriate ratios of methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers; c) adding 1 to 5 parts of benzene or toluene solvent to the total volume of the methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers; d) adding 3mg to 0.3g of benzoyl peroxide catalyst to the reaction mixture; e) refluxing the reaction mixture at 80 to 100°C for 2 to 20 hours under blanket of argon or purified nitrogen gas; and f) decanting the remaining benzene or toluene solvent, washing the crosslink-able MGT co-polymer with petroleum ether.

[35] The ratio of the composition of the crosslinkable high polarity polymer may be

varied. Different ratios of methyl methacrylate (1), glycidyl methacrylate (2) and tetrahydrofurfuryl acrylate (3) monomers to give high polarity crosslink-able polymeric membrane called MGT co-polymer membrane (4) under reflux condition in benzene or toluene in the presence of benzoyl peroxide. In one embodiment, a crosslinkable high polarity MGT co-polymer as the product of the above method in which the ratio of methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by volume is 7:2:1. In another embodiment, a crosslink-able high polarity MGT co-polymer as the product of the above method, in which the ratio of methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by volume is 6:2:2. In another embodiment, a crosslink-able high polarity MGT copolymer as product of the above method, in which the ratio of methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by volume is 5:3:2. In another embodiment, a crosslink-able high polarity MGT co-polymer as product of the above method, in which the ratio of methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by volume is 4:3:3. In another embodiment, a crosslink-able high polarity MGT co-polymer as product of the above method in which the ratio of methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by volume is 3:4:3. In a further embodiment, a crosslink-able high polarity MGT co-polymer as product of the above method, in which the ratio of methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers by volume is 3:3:4.

[36] The use of the MGT high polarity crosslink-able co-polymer product of the above method for the manufacture of solid-state sensing electrodes as thermoset binder. For sensing application important characteristics of binder thermoset copolymer includes ability to conduct electrical signal and curing temperature and time. High polarity monomer such as 3 can reduce the impedance of the membrane. Since polymer of monomer tetrahydrofurfuryl acrylate 3 alone is sticky and gluelike liquid, monomer methyl methacrylate 1 is added in appropriate ratio to harden the copolymer. Monomer glycidyl methacrylate 2 has reactive oxirane group that can reacts with crosslinkers under mild thermal treatment thus thermosetting the copolymer irreversibly to produce hard conductive polymer under heating condition.

[37] Advantageously, the method of preparing high polarity crosslinkable co-polymer of the present invention is economical due to viability of the precursors and availability of low cost and high purity monomers. Advantageously, the physical characteristic of the monomers which are high vapour pressure, low toxicity contributed to ease of handling of the monomers. The method is simple and no further purification required for the copolymer products. One of the advantages of the method of preparation of crosslinkable high polarity polymeric membrane is that the crosslinkable high polarity polymer shows good characteristics as heat curable binder for fabrication of mem- braneless bio-chemical sensing electrodes for continuous environmental monitoring. Solid state sensing electrodes for detection of trace amounts of chemical species without the use of solvent casting or photocured polymeric membrane.

[38] The invention now being generally described, the same will be better understood by reference to the following detailed examples which are provided for purposes of illustration only and are not to be limiting of the invention unless so specified.

[39] The present invention is further described in the following examples and the co- polymerization reaction is shown in Figure 3.

[40]

[41] Example 1

[42] Preparation of Methyl Methacrylate-Tetrahydrofurfuryl Acrylate [43] Copolymer (MGT622)

[44] All chemicals were procured from Sigma-Aldrich Chemical Company and were subject o the following purification method. Methyl methacrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate monomers were first washed three times with saturated sodium bicarbonate solution and twice with brine followed by drying with sodium sulfate, magnesium sulfate and stirred overnight over barium oxide or phosphorus pentoxide or calcium hydride before distillation at atmopheric pressure or under vacuum. Acids and alcohols impurities were effectively removed using this method as clearly shown by H NMR of the monomers.

[45] Purified and freshly distilled methyl methacrylate (1) 6mL , 2 mL of glycidyl

methacrylate (2) and 2 mL of tetrahydrofurfuryl acrylate (3) monomers were added into 50 mL three-neck round bottom flask. Benzene (15 mL ) and 3.7 mg benzoyl peroxide initiator was weighed and dissolved with ImL of benzene and added into the mixture of monomers.

[46] The reaction mixture were slowly heated using heating mantle under continuous flow of argon or purified nitrogen gas and magnetic stirring until a gentle reflux were achieved at 95°C. Reflux and stirring was continued for additional 5 hours and then heating was discontinued and the mixture gradually cooled to room temperature.

[47] The cooled polymeric material was transferred to a 50 mL beaker before it became too viscous. The polymeric material remained as colourless viscous liquid or soft gel and was washed three times with 5 mL portions of petroleum ether (80°C-100°C). The MGT 622 copolymer was air dried at ambient condition over night. The air dried copolymer appears as very viscous liquid shown in Figure 4.

[48] Example 2

[49] Preparation of Methyl Methacrylate-Tetrahydrofurfuryl

[50] Acrylate Copolymer (MGT532)

[51] Purified and freshly distilled (described in Example 1) methyl methacrylate (5 mL, 1 ), 3 mL of glycidyl methacrylate (2) and 2 mL of tetrahydrofurfuryl acrylate (3) monomers were added into 50 mL three-neck round bottom flask. Benzene (15 mL ) and 1 mg benzoyl peroxide initiator were added into the mixture of monomers.

[52] The reaction mixture were slowly heated using heating mantle under continuous flow of argon or purified nitrogen gas and magnetic stirring until a gentle reflux were achieved at 95°C. Reflux and stirring was continued for additional 7 hours and then heating was discontinued and the mixture gradually cooled to room temperature.

[53] The cooled polymeric material was transferred to a 50 mL beaker before it became too viscous. The polymeric material remained as colourless viscous liquid or soft gel and was washed three times with 5 mL portions of petroleum ether (80°C-100°C). The MGT 532 copolymer was air dried at ambient condition over night. The air dried copolymer appears as very viscous liquid shown in Figure 5.

[54] The invention being thus described, it will be apparent that the same may be varied in many ways. Such variations are to be regarded as within the scope of the invention, and all such modifications as would be apparent to one skilled in the art are intended to be within the scope of the following claims:

Best Mode

[55]

Mode for Invention

[56]

Industrial Applicability

[57]

Sequence List Text