Experimental Work
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Experimental Work
CHAPTER 3
EXPERIMENTAL WORK
3.1 Materials 3.1.1 Polyamide Polyamides are semicrystalline commonly used in fiber applications such as carpeting, clothing, and tire cord and also used as an engineering material in bearings and gears due to their good abrasion resistance along with selflubricating properties. Polyamides like (PA 66 & PA 6) (Durathen A30S grade) was procured from Lanxess Polymers, Germany, & supplied by the dealer Ajramer Impex, Mumbai (India). Properties Glass transition temperature: 50oC. Melting temperature: 255oC.
Repeat Unit C12H22O2N2
Amorphous density at 25oC: 1.07 g/cm3. Crystalline density at 25oC: 1.24 g/cm3. Molecular weight of repeat unit: 226.32 g/mol.
Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 51
Experimental Work
3.1.2 Chemicals for nano particle synthesis Analytical grades of calcium chloride, ammonium carbonate ammonium sulfate, magnesium
chloride,
ammonium
hydroxide,
ammonium
phosphate
and
polyethylene glycol (PEG) (mol.wt .6000) were procured from Qualigens India Ltd Mumbai, and used for the synthesis of nano particles of calcium carbonate calcium sulfate, magnesium hydroxide & calcium phosphate respectively. 3.2 Other Commercial Fillers 3.2.1 Commercial CaCO3 Commercial grade of CaCO3 was procured from Mountain Minerals and Microns Ltd, Vadodara, GS, India. This grade is generally used in plastics, rubber and paint industries. Physical properties of calcium carbonate are listed below Color Particle shape Avg particle size Bulk density Specific gravity
White Random 20 µm 0.9 g/cc 2.70
3.2.2 Commercial CaSO4 Commercial grade of CaSO4 was procured from s d fine chemicals, Mumbai, India. Micron size CaSO4 is having needle like structure, and particles size is 40 µm. Following are the physical properties of CaSO4 Color Particle shape Avg particle size Bulk density Specific gravity
White Needle/ fiber like 40 µm 0.9 g/cc 2.02
Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 52
Experimental Work
3.2.3 Commercial Mg (OH) 2 Micro-Mg (OH) 2 was procured from Beijing Fine Chemical Plant, China. The physical properties of Mg (OH) 2 are listed below . Color Particle shape Avg particle size Bulk density Specific gravity
White Hexagonal Sheet like 40 µm 0.9 g/cc 2.00
3.2.4 Commercial Ca3(PO4)2 Commercial grade of Ca3(PO4)2 was procured from Beijing Fine Chemical Plant, China. The physical properties of Ca3(PO4)2 are listed below Color Particle shape Avg particle size Bulk density Specific gravity
White Needle/ fiber like 40 µm 0.9 g/cc 2.02
3.3 Synthesis of Nano Inorganic Filler 3.3.1 Nano CaCO3 Nanosize calcium carbonate was synthesized by in situ deposition technique. Calcium chloride 110 gm (by wt.) was taken in 100 ml water. 248 gm (by wt.) of PEG was diluted by taking 100 ml water and mildly heated for proper mixing. The complex of calcium chloride and polyethylene glycol was prepared in molar ratios (1:4 1:20, 1:32). Another solution of NH4HCO3 was prepared by taking its 79.9 gm in 100 ml of distilled water. The first complex was digested for 12 h then the solution of NH4HCO3 was added slowly and again kept for digestion for 12h. The Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 53
Experimental Work
precipitate was filtered, washed with water and dried in vacuum drier (1-16). Nano synthesis by in situ deposition technique is shown in figure 3.1.
Fig 3.1 Synthesis of Nano CaCO3 by matrix mediated growth technique 3.3.2 Nano CaSO4 Nanosize calcium sulfate was synthesized by in situ deposition technique. Calcium chloride 110 g (by wt.) was taken in 100 ml water. 248 g (by wt.) of PEG was diluted by taking 100 ml water and mildly heated for proper mixing. The complex of calcium chloride and polyethylene glycol was prepared in molar ratios (1:4 1:20, 1:32). Another solution of ammonium sulfate was prepared by taking 132 g in 75 ml of distilled water. The first complex was digested for 12 h then the solution of ammonium sulfate was added slowly and again kept for digestion for 12h. The precipitate was filtered, washed with water and dried in vacuum drier. Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 54
Experimental Work
3.3.3 Nano Mg (OH) 2 Nanosize magnesium hydroxide was synthesized by in situ deposition technique. 203 g magnesium chloride (by wt.) was taken in 100 ml water. 248 gm (by wt.) of PEG was diluted by taking 100 ml water and mildly heated for proper mixing. The complex of MgCl2 and polyethylene glycol was prepared in molar ratios (1:4 1:20, 1:32). Another solution of ammonium sulfate was prepared by taking its 132 gm in 75 ml of distilled water. The first complex was digested for 12 h then the solution of ammonium sulfate was added slowly and again kept for digestion for 12h. The precipitate was filtered, washed with water and dried in vacuum drier.
3.3.4 Nano Ca3(PO4)2 Like magnesium hydroxide nanosize calcium phosphate was synthesized by Insitu deposition technique. 110 g calcium chloride was taken in 140 ml water. 248 g (by wt) of PEG was diluted by taking 200 ml water and mildly heated for proper mixing. The Complex of calcium chloride and polyethylene glycol was prepared in two different molar ratios (1:4, 1:20). Another solution of Ammonium phosphate was prepared by taking 132 gm in 80 ml of water. The first complex of PEG and Calcium chloride solution was digested for 12 h and then second complex was added slowly and kept for digestion for overnight. The precipitate was filtered, washed with water and dried in vacuum. Viscosity of PEG solution was measured with help of Bubble Gardner tubes to confirm the possible
Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 55
Experimental Work
thickening of water soluble matrix. The yield of nano inorganic materials were reported in Table 1.
3.4 Preparation of Polyamide Nanocomposites Compounding of polyamide nanocomposites with various percent loading (premixing) of nano inorganic fillers (CaCO3,CaSO4,Mg(OH)2 & Ca3PO4)2) were carried out on a JSW (Japan Steel Works), Japan made twin screw extruder having diameter of 30 mm, L/D ratio 36:1 having screw speed 335 rpm. Before compounding, polyamide granules were kept in oven to make it moisture free at 80 0C for 3 h. The dumbbell shaped specimen ASTM-D 412 was prepared on injection molding machine, JSW. The screw diameter of molding machine was 40 mm having injection stroke 120 mm, with injection pressure 1570 kg/cm 2. Total cycle time through out the process was 20 sec per sample. 3.5 Characterization of Polyamide Nanocomposites There are many factors, which determine the nature of mechanical behavior of material. These can be divided into two classes viz. intensive and extensive. The former depends on structure, molecular weight, branching, and morphology. The latter depends on temperature, time, stress, strain, and type of deformation.
3.5.1 Tensile test Injection molded tensile specimens as per ASTM-D 412 were tested on universal testing machine, (model UT-2303,R&D Electronics, Mumbai),. Testing was done at room temperature. The Young’s modulus and elongation at break (%) were Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 56
Experimental Work
determined at deformation speed 5.00 cm/min, respectively. The mean value of 5 measurements was taken. All measurements were performed 8 times to obtain average value. The tensile strength & young’s moduli were calculated by the following formula
Where, F= Force, A= Cross-sectional area, L= Change in length, L0= original length of the sample. 3.5.2 Hardness test The molded specimens were tested to report the hardness data using shore hardness (ASTM-D 2240 type). The data obtained represent the average value of 5 test specimens. 3.6 X-Ray Diffraction Pattern For the characterization of the nanoparticles, XRD studies were performed using Miniflex, Regaku (Japan) diffractoremeter in the range of 10-300. The samples were placed vertically in front of the X-ray source. The detector was moving at an angle of 2θ while the sample was moving at an angle of θ. 3.7 Scanning Electron Microscopy (SEM) In order to study the extent of dispersion and agglomeration of nano filler into the polymer matrix, SEM studies were carried out on CEMECA (France) model SU30 at an operation voltage of 20 KV and pressure of 0.98 torr. Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 57
Experimental Work
3.8 Atomic Force Microscopy In order to study the extent of dispersion and agglomeration of nano filler into the polymer matrix, analysis was carried out on Nanosurf AG Switzerland and NTMDT, Russia
3.9 Flame Retardency Flame retardency test was carried out in flame tester (prolific make, Noida, U.P.) India,) as per ASTM D 3801. Sample was clamped with 85 mm above the horizontal screen so that it should not sag out to touch the screen. A free end is exposed to specified gas flame for 30 sec. Sample was clamped at 45 o angle with flame tip. Time required for burning and relative rate of burning was measured. 3.10 Thermal Degradation Thermal degradation measurements were carried out using
Shimadzu
Thermogravimetric analyzer (TGA 50). Temperature programming was done from 0o C- 600oC at heating rate of 5 oC/ min. Testing was carried out under the inert atmosphere to remove all corrosive gases and to avoid thermoxidative degradation.
Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 58
Experimental Work
3.11 Differential Scanning Calorimetry DSC measurements were carried out on Shimadzu DSC (DSC- 60). Glass transition temperatures were determined under cryogenic condition using liquid nitrogen. Temperature programming was done from 0o C to –600 oC at heating rate of 5 oC/ min under inert atmosphere.
Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 59
Experimental Work
References 1.
Saujanya C, Radhakrishnan S, Polymer, 42:6728, 2001
2.
Saujanya C, Radhakrishnan S, J. Material Sci, 33:1063, 1998
3.
Saujanya C Ashmol Radhakrshan S. Polymer Communications 42:2257, 2000
4.
S.Mishra, S.H.Sonawane, R.P.Singh, A.Bendale, K.Patil, J. Appl. Polym. Sci, 94:116, 2004
5.
Pathak A, Panda A. B, Tarafdar A, and Pramanik P, J.Indian Chem. Soc. 80:289, 2003
6.
Das R N, Pathak A, Pramanik P, J American Ceramic Soc. 81:3357,1998
7.
Gleiter H, Nanostructure Mater, 1:1, 1991
8.
Koch C. C, Nanostructure Mater, 21:559, 1991
9.
Ram S, Fecht H J, Febry M, Joubert J C, Nanostructure Mater, 6:470,1995
10.
Liao B, Sang M, Liang H, Pang Y, Polymer, 42:1007-1011, 2001
11.
De G C, Roy A M, Saha S, Sukumar A, J. Indian Chem. Soc, 80:551,2003
12.
Pandya M V, Deshpande D D, Intern J Polymeric Mater, 12:261, 1989.
13.
Mishra S, Sonawane S H & Singh R P, Studies on characterization of nano CaCO3 prepared by in-situ deposition technique and its applications in PP-nano CaCO3 composites, J Polym Sci Part B: Polym Phys, 43:107, 2005
14.
S Mishra* and N G Shimpi, Comparison of nano CaCO3 and with fly ash filled styrene butadiene rubber on mechanical and thermal properties, Journal of Scientific & Industrial Research. 41:744, 2005
15.
Mishra S. and Shimpi N. G. Journal of Applied Polymer Science 98:2563 2005 Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 60
Experimental Work
16.
S. Mishra, N. G. Shimpi Journal of Applied Polymer Science, Vol. 104, 2018–2026, 2007
Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 61
CHAPTER 3
EXPERIMENTAL WORK
3.1 Materials 3.1.1 Polyamide Polyamides are semicrystalline commonly used in fiber applications such as carpeting, clothing, and tire cord and also used as an engineering material in bearings and gears due to their good abrasion resistance along with selflubricating properties. Polyamides like (PA 66 & PA 6) (Durathen A30S grade) was procured from Lanxess Polymers, Germany, & supplied by the dealer Ajramer Impex, Mumbai (India). Properties Glass transition temperature: 50oC. Melting temperature: 255oC.
Repeat Unit C12H22O2N2
Amorphous density at 25oC: 1.07 g/cm3. Crystalline density at 25oC: 1.24 g/cm3. Molecular weight of repeat unit: 226.32 g/mol.
Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 51
Experimental Work
3.1.2 Chemicals for nano particle synthesis Analytical grades of calcium chloride, ammonium carbonate ammonium sulfate, magnesium
chloride,
ammonium
hydroxide,
ammonium
phosphate
and
polyethylene glycol (PEG) (mol.wt .6000) were procured from Qualigens India Ltd Mumbai, and used for the synthesis of nano particles of calcium carbonate calcium sulfate, magnesium hydroxide & calcium phosphate respectively. 3.2 Other Commercial Fillers 3.2.1 Commercial CaCO3 Commercial grade of CaCO3 was procured from Mountain Minerals and Microns Ltd, Vadodara, GS, India. This grade is generally used in plastics, rubber and paint industries. Physical properties of calcium carbonate are listed below Color Particle shape Avg particle size Bulk density Specific gravity
White Random 20 µm 0.9 g/cc 2.70
3.2.2 Commercial CaSO4 Commercial grade of CaSO4 was procured from s d fine chemicals, Mumbai, India. Micron size CaSO4 is having needle like structure, and particles size is 40 µm. Following are the physical properties of CaSO4 Color Particle shape Avg particle size Bulk density Specific gravity
White Needle/ fiber like 40 µm 0.9 g/cc 2.02
Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 52
Experimental Work
3.2.3 Commercial Mg (OH) 2 Micro-Mg (OH) 2 was procured from Beijing Fine Chemical Plant, China. The physical properties of Mg (OH) 2 are listed below . Color Particle shape Avg particle size Bulk density Specific gravity
White Hexagonal Sheet like 40 µm 0.9 g/cc 2.00
3.2.4 Commercial Ca3(PO4)2 Commercial grade of Ca3(PO4)2 was procured from Beijing Fine Chemical Plant, China. The physical properties of Ca3(PO4)2 are listed below Color Particle shape Avg particle size Bulk density Specific gravity
White Needle/ fiber like 40 µm 0.9 g/cc 2.02
3.3 Synthesis of Nano Inorganic Filler 3.3.1 Nano CaCO3 Nanosize calcium carbonate was synthesized by in situ deposition technique. Calcium chloride 110 gm (by wt.) was taken in 100 ml water. 248 gm (by wt.) of PEG was diluted by taking 100 ml water and mildly heated for proper mixing. The complex of calcium chloride and polyethylene glycol was prepared in molar ratios (1:4 1:20, 1:32). Another solution of NH4HCO3 was prepared by taking its 79.9 gm in 100 ml of distilled water. The first complex was digested for 12 h then the solution of NH4HCO3 was added slowly and again kept for digestion for 12h. The Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 53
Experimental Work
precipitate was filtered, washed with water and dried in vacuum drier (1-16). Nano synthesis by in situ deposition technique is shown in figure 3.1.
Fig 3.1 Synthesis of Nano CaCO3 by matrix mediated growth technique 3.3.2 Nano CaSO4 Nanosize calcium sulfate was synthesized by in situ deposition technique. Calcium chloride 110 g (by wt.) was taken in 100 ml water. 248 g (by wt.) of PEG was diluted by taking 100 ml water and mildly heated for proper mixing. The complex of calcium chloride and polyethylene glycol was prepared in molar ratios (1:4 1:20, 1:32). Another solution of ammonium sulfate was prepared by taking 132 g in 75 ml of distilled water. The first complex was digested for 12 h then the solution of ammonium sulfate was added slowly and again kept for digestion for 12h. The precipitate was filtered, washed with water and dried in vacuum drier. Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 54
Experimental Work
3.3.3 Nano Mg (OH) 2 Nanosize magnesium hydroxide was synthesized by in situ deposition technique. 203 g magnesium chloride (by wt.) was taken in 100 ml water. 248 gm (by wt.) of PEG was diluted by taking 100 ml water and mildly heated for proper mixing. The complex of MgCl2 and polyethylene glycol was prepared in molar ratios (1:4 1:20, 1:32). Another solution of ammonium sulfate was prepared by taking its 132 gm in 75 ml of distilled water. The first complex was digested for 12 h then the solution of ammonium sulfate was added slowly and again kept for digestion for 12h. The precipitate was filtered, washed with water and dried in vacuum drier.
3.3.4 Nano Ca3(PO4)2 Like magnesium hydroxide nanosize calcium phosphate was synthesized by Insitu deposition technique. 110 g calcium chloride was taken in 140 ml water. 248 g (by wt) of PEG was diluted by taking 200 ml water and mildly heated for proper mixing. The Complex of calcium chloride and polyethylene glycol was prepared in two different molar ratios (1:4, 1:20). Another solution of Ammonium phosphate was prepared by taking 132 gm in 80 ml of water. The first complex of PEG and Calcium chloride solution was digested for 12 h and then second complex was added slowly and kept for digestion for overnight. The precipitate was filtered, washed with water and dried in vacuum. Viscosity of PEG solution was measured with help of Bubble Gardner tubes to confirm the possible
Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 55
Experimental Work
thickening of water soluble matrix. The yield of nano inorganic materials were reported in Table 1.
3.4 Preparation of Polyamide Nanocomposites Compounding of polyamide nanocomposites with various percent loading (premixing) of nano inorganic fillers (CaCO3,CaSO4,Mg(OH)2 & Ca3PO4)2) were carried out on a JSW (Japan Steel Works), Japan made twin screw extruder having diameter of 30 mm, L/D ratio 36:1 having screw speed 335 rpm. Before compounding, polyamide granules were kept in oven to make it moisture free at 80 0C for 3 h. The dumbbell shaped specimen ASTM-D 412 was prepared on injection molding machine, JSW. The screw diameter of molding machine was 40 mm having injection stroke 120 mm, with injection pressure 1570 kg/cm 2. Total cycle time through out the process was 20 sec per sample. 3.5 Characterization of Polyamide Nanocomposites There are many factors, which determine the nature of mechanical behavior of material. These can be divided into two classes viz. intensive and extensive. The former depends on structure, molecular weight, branching, and morphology. The latter depends on temperature, time, stress, strain, and type of deformation.
3.5.1 Tensile test Injection molded tensile specimens as per ASTM-D 412 were tested on universal testing machine, (model UT-2303,R&D Electronics, Mumbai),. Testing was done at room temperature. The Young’s modulus and elongation at break (%) were Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 56
Experimental Work
determined at deformation speed 5.00 cm/min, respectively. The mean value of 5 measurements was taken. All measurements were performed 8 times to obtain average value. The tensile strength & young’s moduli were calculated by the following formula
Where, F= Force, A= Cross-sectional area, L= Change in length, L0= original length of the sample. 3.5.2 Hardness test The molded specimens were tested to report the hardness data using shore hardness (ASTM-D 2240 type). The data obtained represent the average value of 5 test specimens. 3.6 X-Ray Diffraction Pattern For the characterization of the nanoparticles, XRD studies were performed using Miniflex, Regaku (Japan) diffractoremeter in the range of 10-300. The samples were placed vertically in front of the X-ray source. The detector was moving at an angle of 2θ while the sample was moving at an angle of θ. 3.7 Scanning Electron Microscopy (SEM) In order to study the extent of dispersion and agglomeration of nano filler into the polymer matrix, SEM studies were carried out on CEMECA (France) model SU30 at an operation voltage of 20 KV and pressure of 0.98 torr. Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 57
Experimental Work
3.8 Atomic Force Microscopy In order to study the extent of dispersion and agglomeration of nano filler into the polymer matrix, analysis was carried out on Nanosurf AG Switzerland and NTMDT, Russia
3.9 Flame Retardency Flame retardency test was carried out in flame tester (prolific make, Noida, U.P.) India,) as per ASTM D 3801. Sample was clamped with 85 mm above the horizontal screen so that it should not sag out to touch the screen. A free end is exposed to specified gas flame for 30 sec. Sample was clamped at 45 o angle with flame tip. Time required for burning and relative rate of burning was measured. 3.10 Thermal Degradation Thermal degradation measurements were carried out using
Shimadzu
Thermogravimetric analyzer (TGA 50). Temperature programming was done from 0o C- 600oC at heating rate of 5 oC/ min. Testing was carried out under the inert atmosphere to remove all corrosive gases and to avoid thermoxidative degradation.
Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 58
Experimental Work
3.11 Differential Scanning Calorimetry DSC measurements were carried out on Shimadzu DSC (DSC- 60). Glass transition temperatures were determined under cryogenic condition using liquid nitrogen. Temperature programming was done from 0o C to –600 oC at heating rate of 5 oC/ min under inert atmosphere.
Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 59
Experimental Work
References 1.
Saujanya C, Radhakrishnan S, Polymer, 42:6728, 2001
2.
Saujanya C, Radhakrishnan S, J. Material Sci, 33:1063, 1998
3.
Saujanya C Ashmol Radhakrshan S. Polymer Communications 42:2257, 2000
4.
S.Mishra, S.H.Sonawane, R.P.Singh, A.Bendale, K.Patil, J. Appl. Polym. Sci, 94:116, 2004
5.
Pathak A, Panda A. B, Tarafdar A, and Pramanik P, J.Indian Chem. Soc. 80:289, 2003
6.
Das R N, Pathak A, Pramanik P, J American Ceramic Soc. 81:3357,1998
7.
Gleiter H, Nanostructure Mater, 1:1, 1991
8.
Koch C. C, Nanostructure Mater, 21:559, 1991
9.
Ram S, Fecht H J, Febry M, Joubert J C, Nanostructure Mater, 6:470,1995
10.
Liao B, Sang M, Liang H, Pang Y, Polymer, 42:1007-1011, 2001
11.
De G C, Roy A M, Saha S, Sukumar A, J. Indian Chem. Soc, 80:551,2003
12.
Pandya M V, Deshpande D D, Intern J Polymeric Mater, 12:261, 1989.
13.
Mishra S, Sonawane S H & Singh R P, Studies on characterization of nano CaCO3 prepared by in-situ deposition technique and its applications in PP-nano CaCO3 composites, J Polym Sci Part B: Polym Phys, 43:107, 2005
14.
S Mishra* and N G Shimpi, Comparison of nano CaCO3 and with fly ash filled styrene butadiene rubber on mechanical and thermal properties, Journal of Scientific & Industrial Research. 41:744, 2005
15.
Mishra S. and Shimpi N. G. Journal of Applied Polymer Science 98:2563 2005 Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 60
Experimental Work
16.
S. Mishra, N. G. Shimpi Journal of Applied Polymer Science, Vol. 104, 2018–2026, 2007
Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon
Page 61
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