Indian Patents. 260128:A PROCESS FOR THE PREPARATION OF ACRYLATE- AMINO ACID NANOPARTICLE COPOLYMER DISPERSION FOR INDUSTRIAL APPLICATIONS

Title of Invention	A PROCESS FOR THE PREPARATION OF ACRYLATE- AMINO ACID NANOPARTICLE COPOLYMER DISPERSION FOR INDUSTRIAL APPLICATIONS
Abstract	Polymerizable amino acid is copolymerised with water insoluble acrylate monomer, taken in the form of aqueous dispersion, under controlled conditions to prepare nanoparticle dispersion, which is facilitated by the typical interfacial coverage afforded from selected amino acid. The resulting dispersion finds enormous industrial applications in leather processing industry, textile industry.

Full Text	Field of the Invention The present invention relates to a process for the preparation of acrylate -amino acid copolymer in the form of aqueous dispersion. Particularly, the invention relates to a process for the preparation of acrylate -amino acid copolymer in the form of aqueous dispersion having average particle size as low as 40nm. The copolymer of the present invention is envisaged to have potential application in leather processing industry as retanning agents for imparting fiber compaction, fullness and buffing property. The copolymer also may find application in textile industry. Background of the Invention Reference may be made to Chern et al (Journal of Polymer Science, Part A: Polymer Chemistry, 39, 898, 2001), who employed non reactive alcohol hexanol in aqueous medium using known initiators at temperature of 70 -80 °C in presence of known surfactants to prepare nanoparticle aqueous acrylate/vinyl copolymer dispersions having particle size in the range of 35 - 50nm. The major limitation associated with the process is that this process involves non polymerizable alcohol which lacks reactivity and gets physically adsorbed on the polymeric dispersion leading to undesirable separation of polymeric particles with change in pH and on storage for a period of about 3 months. Attempts have been made by Larpent et.al. (Macromolecules, 30, 354, 1997} who substituted non polymerizable alcohol with reactive monomers like hydroxy ethyl /propyl acrylate to copolymerize vinyl monomers or a mixture of vinyl and acrylate monomers at temperature of 30 - 40 °C to form nanoparticle vinyl - acrylate polymer dispersion having particle size in the range of 12 -80nm. The major limitation associated with this process is that while the process involves hydroxyl acrylate monomers which are non ionic in nature, and the resulting dispersion lacks charge dependent reactivity characteristics. Moreover, this process is suitable for mainly vinyl monomers like styrene in combination with acrylate monomers having chain length of a maximum of C4, oil soluble acrylate monomers having alkyl chain length of more than C4 cannot be polymerized by this process. Reference may be made to Antonietti et al (Langmuir,10, 2498, 1994), who prepared nanoparticle polystyrene dispersion having particle size in the range of 12 -40nm using lecithin and sodium cholate in presence of known initiator at a temperature in the range of 60- 80°C. The major limitation of the process is that the process is reported only for vinyl monomer like styrene and is not applicable for acrylate monomers having much longer chain length more than C4. Furthermore, the process involves use of non polymerizable species of lecithin which gets physically adsorbed on the polymeric particles. No prior art is available on the preparation of nanoparticle polymeric dispersion having a high coverage of reactive functional sites that exhibit charge characteristics. Such a process demands choice of polymerizable comonomer consisting of reactive functional groups like -COOH group, and capable of providing unique interfacial coverage on the acrylate monomer and polymeric particle. Objects of the Invention The main object of the present investigation is to provide a process for the preparation of acrylate - amino acid nanoparticle copolymer dispersion for industrial applications, which obviates the limitations as detailed above. Another object of the present invention is to provide a process for making nanoparticle acrylate copolymer dispersion using polymerizable amino acid to provide coverage with reactive functional sites, exhibiting chemical binding and providing typical interfacial coverage to polymeric matrix, thus enabling extraordinary stability. Still another object of the present invention is to provide a process for making aqueous nanoparticle polymeric dispersion with particle size distribution as low as 40 nm. Summary of the Invention Accordingly, the present invention provides a process for the preparation of acrylate -amino acid nanoparticle copolymer dispersion for industrial applications which comprises copolymerizing aqueous dispersion of water insoluble acrylate monomer having C4 - Ci8 alkyl chain with 1-10 parts by weight of polymerizable amino acid, having ethylenic linkage, the amino acid being selected from acidic, basic, neutral amino acid, in the presence of surfactant, with surfactant to water insoluble acrylate ratio in the range of 0.3 - 1.0 (w/w), either thermally at a temperature in the range of 40 - 90°C using radical initiator in the range of 0.1-5% (w/w), or through irradiation by known method using 0.01-2% w/w of photo and/or free radical initiator at a temperature in the range of 25-40°C to obtain the desired acrylate -amino acid nanoparticle copolymer dispersion. In an embodiment of the present invention, the water insoluble acrylate monomer used is selected from the group consisting of butyl acrylate, dodecyl acrylate, octadecyl acrylate, and combination there of. In yet another embodiment of the present invention, the amount of water used for the preparation of aqueous solution in polymerization reaction is in the range of 70-85%w/w. In still another embodiment of the present invention the amino acid used is selected from the group consisting of glycine, alanine, leucine, norleucine, isoleucine, and combination there of. In still another embodiment of the present invention, the ratio of acrylate monomer to amino acid used is in the range of 1:1 to 1:5. In still another embodiment of the present invention, the known surfactant used is selected from the group consisting of sodium dodecyl sulfate, cetyl trimethyl ammonium bromide, and t-octyl phenyl polyethylene glycol ether. In still another embodiment of the present invention, the free radical initiator used is selected from the group consisting of potassium persulphate, azo bis iso butyro nitrile(AIBN), ascorbic acid and azo valeric acid. In still another embodiment of the present invention, the photo initiator used is selected from 2,2 dimethoxy 2-phenyl acetophenone, and azo bis iso butyro nitrile. In still another embodiment of the present invention, the source of the irradiation is selected from UV-visible and Gamma radiation. In still another embodiment of the present invention, the acrylate -amino acid nanoparticle copolymer dispersion obtained has average particle size distribution in the range of 40-90 nm. Detailed description of the invention Water insoluble acrylate monomer having C4 -Ci8 alkyl chain is added to surfactant solution prepared by dissolving known surfactant in water, the weight of water is in range of 70-85% w/w of solution to form dispersion. Known surfactant is used in such a way that the weight ratio of surfactant to water insoluble acrylate is in the range of 0.3 - 1.0. This is treated with 1 - 2 parts by weight of polymerizable amino acid, having ethylenic linkage. The amino acid is selected from acidic, basic, neutral amino acid. The copolymerization is carried out for a duration of 3 - 10hrs either by thermal process at a temperature in the range of 25 - 90°C using 0.1 -5%w/w, of known free radical initiator or through irradiation by known method using 0.01-2% w/w of photo and/or free radical initiator on the weight of water insoluble monomer at a temperature in the range of 25-40°C to form acrylate -amino acid nanoparticle copolymer dispersion. The inventive step of the present invention lies in the selection and use of polymerizable amino acid which by virtue of typical interfacial coverage facilitates generation of nanoparticle dispersion through copolymerization reaction with long chain water insoluble acrylate. The following examples are given by way of illustration only and therefore should not be construed to limit the scope of the present invention. Example 1 0.5 g sodium dodecyl sulphate was added to 8g water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 0.5 g of dodecyl acrylate was added to surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion. 1.0g of N-glycinyl maleamic acid was slowly added to it. O.OOOSg of initiator potassium persulfate was added to the flask with continuous stirring. pH of the mixture was found to be 5.5. This was then heated to a temperature of 60°C under inert atmosphere. After a period of 3 hours, the free flowing liquid of dodecyl acrylate-N-glycinyl maleamic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions. The characteristics of the dispersion were found to be as follows pH - 4.6, r\|r - 3.5, Particle size distribution - 40nm, Surface tension - 29.2mN/m. Example 2 0.6 g of cetyl trimethyl ammonium bromide was added to 25 g of water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 2.0 g of butyl acrylate was added to surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion. 2.0g of N-alanyl maleamic acid was slowly added to it. O.OSg of initiator azo valeric acid was added to the flask with continuous stirring. pH of the mixture was found to be 5.5. This was then heated to a temperature of 90°C under inert atmosphere. After a period of 10 hours, the free flowing liquid of butyl acrylate -N-alanyl maleamic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions. The characteristics of the dispersion were found to be as follows pH - 4.8, r\|r - 5.4, Particle size distribution - 45nm, Surface tension - 29.2mN/m. Example 3 1 .Og of t-octyl phenyl poly ethylene glycol ether was added to 9g of water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 1.0g of octadecyl acrylate was added to surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion. 2.0g of N-norleucinyl maleamic acid was slowly added to it. 0.0001 g of initiator 2,2 dimethoxy 2-phenyl acetophenone, was added to the flask with continuous stirring. pH of the mixture was found to be 5.5. This was then irradiated with light of UV radiation at 25 °C under inert atmosphere. After a period of 6 hours, the free flowing liquid of octadecyl acrylate - N-norleucine maleamic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions. The characteristics of the dispersion were found to be as follows pH - 5.2, TV - 7.2, Particle size distribution - 90nm, Surface tension - 28.2mN/m Example 4 1.0 g of sodium dodecyl sulphate was added to 15g of water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 0.5 g of dodecyl acrylate and 0.5 g of butyl acrylate were added in sequence to surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion. 1.0g of N-valine maleamic acid and 0.5 g of N-glutamic acid maleamic acid were slowly added to it. 0.02g of initiator ascorbic acid was added to the flask with continuous stirring. pH of the mixture was found to be 5.5. This was reacted at a temperature of 40°C under gamma radiation. After a period of 10 hours, the free flowing liquid of dodecyl acrylate-butyl acrylate N-valine maleamic acid - N-glutamic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions. The characteristics of the dispersion were found to be as follows pH - 4.5, TV - 3.5, Particle size distribution - 75nm, Surface tension - 26.2mN/m Example 5 1.5g of t-octyl phenyl poly ethylene glycol ether was added to 12.5 g of water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 1.5 g octadecyl acrylate and 0.5 g butyl acrylate were added to surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion. 2.0g of N-lysine maleamic acid was slowly added to it. O.OOIg of initiator 2,2 dimethoxy 2-phenyl acetophenone was added to the flask with continuous stirring. pH of the mixture was found to be 5.5. This was then irradiated with UV radiation at 30 °C under inert atmosphere. After a period of 7 hours, the free flowing liquid of octadecyl acrylate - butyl acrylate - N-lysine maleamic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions. The characteristics of dispersions were found to be as follows. pH - 5.2, T\|r - 7.2, particle size distribution - 120nm, surface tension-28.2 mN/m Example 6 1 .Og of cetyl trimethyl ammonium bromide was added to 15g of water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 2.0g of butyl acrylate was added to surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion. 2.0g of N-aspartic acid - maleamic acid was slowly added to it and 0.1g of initiator azo bis iso butyro nitrite was added to the flask with continuous stirring. pH of the mixture was found to be 5.3. This was then heated to a temperature of 90°C under inert atmosphere. After a period of Shours, the free flowing liquid of butyl acrylate - N-aspartic acid- maleamic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions. The characteristics of dispersions were found to be as follows pH - 4.6, TV - 5.4,Particle size distribution - 100nm, surface tension- 27.2 mN/m. Example 7 0.75g of t-octyl phenyl poly ethylene glycol ether was added to 20 g of water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 1.0 g octadecyl acrylate was added to surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion. 1.0g of N-isoleucine - maleamic acid and 1.0g of N-glutamic acid maleamic acid were slowly added to it. 0.02g of initiator azo valeric acid was added to the flask with continuous stirring. pH of the mixture was found to be 5.3. This was then heated to a temperature of 75°C under inert atmosphere. After a period of 10 hours, the free flowing liquid of octadecyl acrylate - N-isoleucine maleamic acid - N-glutamic acid malemic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions. The characteristics of dispersions were found to be as follows pH-5.2, - 8.2, particle size distribution - 60nm, surface tension - 29.2mN/m The main advantages of the present invention are: 1. The process involves comonomer from amino acid/peptide derivative which is biodegradable. 2. The process involves use of only aqueous solvent and does not involve harmful organic solvents. 3. The properties of polymeric latex from this process can be tuned as a function ofpH. 4. The polymeric latex generated from this process can be modified through chemical reaction. 5. The nanoparticle acrylate dispersion from the process exhibits extraordinary stability of more than 18 months. 6. The process of the present invention is very simple and involves no difficult parameter. 7. The process is very economical. 8. The novel poly acrylate-amino acid derivative used in leather processing results in improved softness and fullness. 9. The process involves low surfactant /monomer ratio to generate acrylate polymer particle with size distribution as low as 40nm and therefore, contributes to considerable reduction in pollution. We claim 1) A process for the preparation of acrylate -amino acid nanoparticle copolymer dispersion for industrial applications which comprises copolymerizing aqueous dispersion of water insoluble acrylate monomer having C4- C18 alkyl chain with 1-10 parts by weight of polymerizable amino acid, having ethylenic linkage, the amino acid being selected from acidic, basic and neutral amino acid, in the presence of surfactant, with surfactant to water insoluble acrylate ratio in the range of 0.3 - 1.0 (w/w), either thermally, at a temperature in the range of 40 - 90°C using radical initiator in the range of 0.1-5% (w/w), or through irradiation by known method using 0.01-2% w/w of photo and/or free radical initiator, at a temperature in the range of 25~4Q°C to obtain the desired acrylate -amino acid nanoparticle copolymer dispersion. 2) A process, as claimed in claim 1, wherein the water insoluble acrylate monomer used is selected from the group consisting of butyl acrylate, dodecyl acrylate, octadecyl acrylate and combination there of. 3) A process, as claimed in claims 1 and 2, wherein the amount of water used for the preparation of aqueous solution in polymerization reaction is in the range of 70-85%w/w. 4) A process, as claimed in claims 1 to 3, wherein the amino acid used is selected from the group consisting of glycine, alanine, leucine, norleucine, isoleucine and combination there of. 5) A process, as claimed in claims 1 to 4, wherein the ratio of acrylate monomer to amino acid used is in the range of 1:1 to 1:5. 6) A process, as claimed in claims 1 to 5, wherein the surfactant used is selected from the group consisting of sodium dodecyl sulfate, cetyl trimethyl ammonium bromide, and t-octyl phenyl polyethylene glycol ether. 7) A process, as claimed in claims 1 to 6, wherein the free radical initiator used is selected from the group consisting of potassium persulphate, azo bis iso butyro nitrile(AIBN), ascorbic acid and azo valeric acid. 8) A process, as claimed in claims 1 to 7, wherein the photo initiator used is selected from 2,2 dimethoxy 2-phenyl acetophenone and azo bis isobutyro nitrile. 9) A process, as claimed in claims 1 to 8, wherein the source of the irradiation used is selected from UV-visible and Gamma radiation. 10)A process, as claimed in Claims 1 to 9, wherein the acrylate -amino acid nanoparticle copolymer dispersion obtained has average particle size distribution in the range of 40-90 nm. 11)A process for the preparation of acrylate -amino acid nanoparticle copolymer dispersion for industrial applications, substantially as herein described with reference to the examples.

Full Text

Field of the Invention
The present invention relates to a process for the preparation of acrylate -amino acid copolymer in the form of aqueous dispersion. Particularly, the invention relates to a process for the preparation of acrylate -amino acid copolymer in the form of aqueous dispersion having average particle size as low as 40nm. The copolymer of the present invention is envisaged to have potential application in leather processing industry as retanning agents for imparting fiber compaction, fullness and buffing property. The copolymer also may find application in textile industry.
Background of the Invention
Reference may be made to Chern et al (Journal of Polymer Science, Part A: Polymer Chemistry, 39, 898, 2001), who employed non reactive alcohol hexanol in aqueous medium using known initiators at temperature of 70 -80 °C in presence of known surfactants to prepare nanoparticle aqueous acrylate/vinyl copolymer dispersions having particle size in the range of 35 - 50nm. The major limitation associated with the process is that this process involves non polymerizable alcohol which lacks reactivity and gets physically adsorbed on the polymeric dispersion leading to undesirable separation of polymeric particles with change in pH and on storage for a period of about 3 months.
Attempts have been made by Larpent et.al. (Macromolecules, 30, 354, 1997} who substituted non polymerizable alcohol with reactive monomers like hydroxy ethyl /propyl acrylate to copolymerize vinyl monomers or a mixture of vinyl and acrylate monomers at temperature of 30 - 40 °C to form nanoparticle vinyl - acrylate polymer dispersion having particle size in the range of 12 -80nm. The major limitation associated with this process is that while the process involves hydroxyl acrylate monomers which are non ionic in nature, and the resulting dispersion lacks charge dependent reactivity characteristics. Moreover, this process is suitable for mainly vinyl monomers like styrene in combination with acrylate monomers having chain length of a maximum of C4, oil soluble acrylate monomers having alkyl chain length of more than C4 cannot be polymerized by this process.

Reference may be made to Antonietti et al (Langmuir,10, 2498, 1994), who prepared nanoparticle polystyrene dispersion having particle size in the range of 12 -40nm using lecithin and sodium cholate in presence of known initiator at a temperature in the range of 60- 80°C. The major limitation of the process is that the process is reported only for vinyl monomer like styrene and is not applicable for acrylate monomers having much longer chain length more than C4. Furthermore, the process involves use of non polymerizable species of lecithin which gets physically adsorbed on the polymeric particles.
No prior art is available on the preparation of nanoparticle polymeric dispersion having a high coverage of reactive functional sites that exhibit charge characteristics. Such a process demands choice of polymerizable comonomer consisting of reactive functional groups like -COOH group, and capable of providing unique interfacial coverage on the acrylate monomer and polymeric particle.
Objects of the Invention
The main object of the present investigation is to provide a process for the preparation of acrylate - amino acid nanoparticle copolymer dispersion for industrial applications, which obviates the limitations as detailed above.
Another object of the present invention is to provide a process for making nanoparticle acrylate copolymer dispersion using polymerizable amino acid to provide coverage with reactive functional sites, exhibiting chemical binding and providing typical interfacial coverage to polymeric matrix, thus enabling extraordinary stability.
Still another object of the present invention is to provide a process for making aqueous nanoparticle polymeric dispersion with particle size distribution as low as 40 nm.
Summary of the Invention
Accordingly, the present invention provides a process for the preparation of acrylate -amino acid nanoparticle copolymer dispersion for industrial applications

which comprises copolymerizing aqueous dispersion of water insoluble acrylate monomer having C4 - Ci8 alkyl chain with 1-10 parts by weight of polymerizable amino acid, having ethylenic linkage, the amino acid being selected from acidic, basic, neutral amino acid, in the presence of surfactant, with surfactant to water insoluble acrylate ratio in the range of 0.3 - 1.0 (w/w), either thermally at a temperature in the range of 40 - 90°C using radical initiator in the range of 0.1-5% (w/w), or through irradiation by known method using 0.01-2% w/w of photo and/or free radical initiator at a temperature in the range of 25-40°C to obtain the desired acrylate -amino acid nanoparticle copolymer dispersion.
In an embodiment of the present invention, the water insoluble acrylate monomer used is selected from the group consisting of butyl acrylate, dodecyl acrylate, octadecyl acrylate, and combination there of.
In yet another embodiment of the present invention, the amount of water used for the preparation of aqueous solution in polymerization reaction is in the range of 70-85%w/w.
In still another embodiment of the present invention the amino acid used is selected from the group consisting of glycine, alanine, leucine, norleucine, isoleucine, and combination there of.
In still another embodiment of the present invention, the ratio of acrylate monomer to amino acid used is in the range of 1:1 to 1:5.
In still another embodiment of the present invention, the known surfactant used is selected from the group consisting of sodium dodecyl sulfate, cetyl trimethyl ammonium bromide, and t-octyl phenyl polyethylene glycol ether.
In still another embodiment of the present invention, the free radical initiator used is selected from the group consisting of potassium persulphate, azo bis iso butyro nitrile(AIBN), ascorbic acid and azo valeric acid.
In still another embodiment of the present invention, the photo initiator used is selected from 2,2 dimethoxy 2-phenyl acetophenone, and azo bis iso butyro nitrile.
In still another embodiment of the present invention, the source of the irradiation is selected from UV-visible and Gamma radiation.

In still another embodiment of the present invention, the acrylate -amino acid nanoparticle copolymer dispersion obtained has average particle size distribution in the range of 40-90 nm.
Detailed description of the invention
Water insoluble acrylate monomer having C4 -Ci8 alkyl chain is added to surfactant solution prepared by dissolving known surfactant in water, the weight of water is in range of 70-85% w/w of solution to form dispersion. Known surfactant is used in such a way that the weight ratio of surfactant to water insoluble acrylate is in the range of 0.3 - 1.0. This is treated with 1 - 2 parts by weight of polymerizable amino acid, having ethylenic linkage. The amino acid is selected from acidic, basic, neutral amino acid. The copolymerization is carried out for a duration of 3 - 10hrs either by thermal process at a temperature in the range of 25 - 90°C using 0.1 -5%w/w, of known free radical initiator or through irradiation by known method using 0.01-2% w/w of photo and/or free radical initiator on the weight of water insoluble monomer at a temperature in the range of 25-40°C to form acrylate -amino acid nanoparticle copolymer dispersion.
The inventive step of the present invention lies in the selection and use of polymerizable amino acid which by virtue of typical interfacial coverage facilitates generation of nanoparticle dispersion through copolymerization reaction with long chain water insoluble acrylate.
The following examples are given by way of illustration only and therefore should not be construed to limit the scope of the present invention.
Example 1
0.5 g sodium dodecyl sulphate was added to 8g water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 0.5 g of dodecyl acrylate was added to surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion.

1.0g of N-glycinyl maleamic acid was slowly added to it. O.OOOSg of initiator potassium persulfate was added to the flask with continuous stirring. pH of the mixture was found to be 5.5. This was then heated to a temperature of 60°C under inert atmosphere. After a period of 3 hours, the free flowing liquid of dodecyl acrylate-N-glycinyl maleamic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions.
The characteristics of the dispersion were found to be as follows pH - 4.6, r|r - 3.5, Particle size distribution - 40nm, Surface tension - 29.2mN/m.
Example 2
0.6 g of cetyl trimethyl ammonium bromide was added to 25 g of water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 2.0 g of butyl acrylate was added to
surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion. 2.0g of N-alanyl maleamic acid was slowly added to it. O.OSg of initiator azo valeric acid was added to the flask with continuous stirring. pH of the mixture was found to be 5.5. This was then heated to a temperature of 90°C under inert atmosphere. After a period of 10 hours, the free flowing liquid of butyl acrylate -N-alanyl maleamic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions.
The characteristics of the dispersion were found to be as follows
pH - 4.8, r|r - 5.4, Particle size distribution - 45nm, Surface tension - 29.2mN/m.
Example 3
1 .Og of t-octyl phenyl poly ethylene glycol ether was added to 9g of water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 1.0g of octadecyl acrylate was added to surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion. 2.0g of N-norleucinyl maleamic acid was slowly added to it. 0.0001 g of initiator 2,2 dimethoxy 2-phenyl acetophenone, was added to the flask with continuous stirring. pH of the mixture was found to be 5.5. This was then

irradiated with light of UV radiation at 25 °C under inert atmosphere. After a period of 6 hours, the free flowing liquid of octadecyl acrylate - N-norleucine maleamic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions.
The characteristics of the dispersion were found to be as follows pH - 5.2, TV - 7.2, Particle size distribution - 90nm, Surface tension - 28.2mN/m
Example 4
1.0 g of sodium dodecyl sulphate was added to 15g of water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 0.5 g of dodecyl acrylate and 0.5 g of butyl acrylate were added in sequence to surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion. 1.0g of N-valine maleamic acid and 0.5 g of N-glutamic acid maleamic acid were slowly added to it. 0.02g of initiator ascorbic acid was added to the flask with continuous stirring. pH of the mixture was found to be 5.5. This was reacted at a temperature of 40°C under gamma radiation. After a period of 10 hours, the free flowing liquid of dodecyl acrylate-butyl acrylate N-valine maleamic acid - N-glutamic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions.
The characteristics of the dispersion were found to be as follows pH - 4.5, TV - 3.5, Particle size distribution - 75nm, Surface tension - 26.2mN/m
Example 5
1.5g of t-octyl phenyl poly ethylene glycol ether was added to 12.5 g of water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 1.5 g octadecyl acrylate and 0.5 g butyl acrylate were added to surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion. 2.0g of N-lysine maleamic acid was slowly added to it. O.OOIg of initiator 2,2 dimethoxy 2-phenyl acetophenone was added to the flask with continuous stirring. pH of the mixture was found to be 5.5.

This was then irradiated with UV radiation at 30 °C under inert atmosphere. After a period of 7 hours, the free flowing liquid of octadecyl acrylate - butyl acrylate - N-lysine maleamic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions.
The characteristics of dispersions were found to be as follows. pH - 5.2, T|r - 7.2, particle size distribution - 120nm, surface tension-28.2 mN/m
Example 6
1 .Og of cetyl trimethyl ammonium bromide was added to 15g of water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 2.0g of butyl acrylate was added to surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion. 2.0g of N-aspartic acid - maleamic acid was slowly added to it and 0.1g of initiator azo bis iso butyro nitrite was added to the flask with continuous stirring. pH of the mixture was found to be 5.3. This was then heated to a temperature of 90°C under inert atmosphere. After a period of Shours, the free flowing liquid of butyl acrylate - N-aspartic acid- maleamic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions. The characteristics of dispersions were found to be as follows pH - 4.6, TV - 5.4,Particle size distribution - 100nm, surface tension- 27.2 mN/m.
Example 7
0.75g of t-octyl phenyl poly ethylene glycol ether was added to 20 g of water taken in a three necked flask provided with a stirrer, thermometer and inlet for inert gas. The solution was stirred to form uniform dispersion. 1.0 g octadecyl acrylate was added to surfactant solution in the three necked flask under continuous stirring so as to form uniform dispersion. 1.0g of N-isoleucine - maleamic acid and 1.0g of N-glutamic acid maleamic acid were slowly added to it. 0.02g of initiator azo valeric acid was added to the flask with continuous stirring. pH of the mixture was found to be 5.3. This was then heated to a temperature of 75°C under inert atmosphere. After a period of 10 hours, the free flowing liquid of octadecyl acrylate - N-isoleucine

maleamic acid - N-glutamic acid malemic acid nanoparticle copolymer dispersion was collected in a plastic container and stored under air tight conditions.
The characteristics of dispersions were found to be as follows pH-5.2, - 8.2, particle size distribution - 60nm, surface tension - 29.2mN/m
The main advantages of the present invention are:
1. The process involves comonomer from amino acid/peptide derivative which is
biodegradable.
2. The process involves use of only aqueous solvent and does not involve
harmful organic solvents.
3. The properties of polymeric latex from this process can be tuned as a function
ofpH.
4. The polymeric latex generated from this process can be modified through
chemical reaction.
5. The nanoparticle acrylate dispersion from the process exhibits extraordinary
stability of more than 18 months.
6. The process of the present invention is very simple and involves no difficult
parameter.
7. The process is very economical.
8. The novel poly acrylate-amino acid derivative used in leather processing results
in improved softness and fullness.
9. The process involves low surfactant /monomer ratio to generate acrylate
polymer particle with size distribution as low as 40nm and therefore,
contributes to considerable reduction in pollution.

We claim
1) A process for the preparation of acrylate -amino acid nanoparticle copolymer
dispersion for industrial applications which comprises copolymerizing aqueous
dispersion of water insoluble acrylate monomer having C4- C18 alkyl chain with
1-10 parts by weight of polymerizable amino acid, having ethylenic linkage, the
amino acid being selected from acidic, basic and neutral amino acid, in the
presence of surfactant, with surfactant to water insoluble acrylate ratio in the
range of 0.3 - 1.0 (w/w), either thermally, at a temperature in the range of 40 -
90°C using radical initiator in the range of 0.1-5% (w/w), or through irradiation
by known method using 0.01-2% w/w of photo and/or free radical initiator, at a
temperature in the range of 25~4Q°C to obtain the desired acrylate -amino
acid nanoparticle copolymer dispersion.
2) A process, as claimed in claim 1, wherein the water insoluble acrylate
monomer used is selected from the group consisting of butyl acrylate, dodecyl
acrylate, octadecyl acrylate and combination there of.
3) A process, as claimed in claims 1 and 2, wherein the amount of water used for
the preparation of aqueous solution in polymerization reaction is in the range
of 70-85%w/w.
4) A process, as claimed in claims 1 to 3, wherein the amino acid used is
selected from the group consisting of glycine, alanine, leucine, norleucine,
isoleucine and combination there of.
5) A process, as claimed in claims 1 to 4, wherein the ratio of acrylate monomer
to amino acid used is in the range of 1:1 to 1:5.
6) A process, as claimed in claims 1 to 5, wherein the surfactant used is selected
from the group consisting of sodium dodecyl sulfate, cetyl trimethyl ammonium
bromide, and t-octyl phenyl polyethylene glycol ether.
7) A process, as claimed in claims 1 to 6, wherein the free radical initiator used is
selected from the group consisting of potassium persulphate, azo bis iso
butyro nitrile(AIBN), ascorbic acid and azo valeric acid.
8) A process, as claimed in claims 1 to 7, wherein the photo initiator used is
selected from 2,2 dimethoxy 2-phenyl acetophenone and azo bis isobutyro
nitrile.
9) A process, as claimed in claims 1 to 8, wherein the source of the irradiation
used is selected from UV-visible and Gamma radiation.
10)A process, as claimed in Claims 1 to 9, wherein the acrylate -amino acid
nanoparticle copolymer dispersion obtained has average particle size
distribution in the range of 40-90 nm. 11)A process for the preparation of acrylate -amino acid nanoparticle copolymer
dispersion for industrial applications, substantially as herein described with
reference to the examples.

Documents:

388-del-2006-Abstract-(10-09-2012).pdf

388-del-2006-abstract.pdf

388-del-2006-Claims-(10-09-2012).pdf

388-del-2006-claims.pdf

388-del-2006-Correspondence Others-(10-09-2012).pdf

388-DEL-2006-Correspondence-Others 1.pdf

388-del-2006-correspondence-others.pdf

388-del-2006-description (complete).pdf

388-del-2006-description (provisional).pdf

388-del-2006-form-1.pdf

388-del-2006-form-18.pdf

388-del-2006-form-2.pdf

388-del-2006-form-3.pdf

388-del-2006-form-5.pdf

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Patent Number

260128

Indian Patent Application Number

388/DEL/2006

PG Journal Number

14/2014

Publication Date

04-Apr-2014

Grant Date

31-Mar-2014

Date of Filing

13-Feb-2006

Name of Patentee

COUNCIL OF SCIENTIFIC & INDUSTRIAL RESEARCH

Applicant Address

ANUSANDHAN BHAWAN, RAFI MARG, NEW DELHI-110001, INDIA.

Inventors:

#	Inventor's Name	Inventor's Address
1	SANJEEV GUPTA	CENTRAL LEATHER RESEARCH INSTITUTE, ADYAR, CHENNAI-600020, INDIA.
2	GEETHA BASKAR	CENTRAL LEATHER RESEARCH INSTITUTE, ADYAR, CHENNAI-600020, INDIA.
3	LOURDUSAMY JOSEPH MILTON GASPAR	CENTRAL LEATHER RESEARCH INSTITUTE, ADYAR, CHENNAI-600020, INDIA.
4	JAMES KANAGARAJ	CENTRAL LEATHER RESEARCH INSTITUTE, ADYAR, CHENNAI-600020, INDIA.
5	BOREDDY SIVA RAMI REDDY	CENTRAL LEATHER RESEARCH INSTITUTE, ADYAR, CHENNAI-600020, INDIA.
6	ASIT BARAN MANDAL	CENTRAL LEATHER RESEARCH INSTITUTE, ADYAR, CHENNAI-600020, INDIA.
7	NARASIMHAN KANNAN CHANDRABABU	CENTRAL LEATHER RESEARCH INSTITUTE, ADYAR, CHENNAI-600020, INDIA.

PCT International Classification Number

C08F 20/56

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA