Microsoft Word - B_24_R.doc HUNGARIAN JOURNAL OF INDUSTRIAL CHEMISTRY VESZPRÉM Vol. 38(2). pp. 175-179 (2010) THE PRODUCTION AND INVESTIGATION OF STARCH BASED SLOW RELEASED ENCAPSULATING AGENTS M. MEICZINGER , GY. MARTON† Research Institute of Chemical and Process Engineering, University of Pannonia, POB 158, Veszprém, H8201, HUNGARY E-mail: moni@meiczinger.hu Nowadays the protection of environmentally aware has important part in the agriculture. The growth of the plants need fill the gap of soil’s nutrient. His manner included for this the fertilizing. The most developed fertilizers contain the essential microelements (B, Mn, Zn, Cu, Co, Mo), which are needed for plants, and provide their slow releasing. The native starch is a natural biopolymer that can be gained from renewable raw materials. Its good property is that the native starch able to slow the releasing of the micro components. This effect can be improved if the starch gets ionic functional groups that are able to bind cations. Different starch-phosphates were produced in solid-phase modification with changing the conditions, than we investigated the quality of these starch-phosphates (molecular weight distribution, charge density, solubility). We added copper and zinc microelements to these products using ion exchange method, and examined the dissolution of the micro components. In this paper we present our experiences about dissolution of the zinc and copper in different pH. Keywords: slow release, encapsulating agent, starch derivatives Introduction For many years our research group deals with the improvement of starch derivatives, which are able to slow release of micro components as fertilizers. The plants use the microelements in a minimal quantity, but their presence is essential to their growth. Starch based encapsulating agents are organic or inorganic esters that have the capability of controlled water-repellency. With the use of them, we can reduce the speed of bioactive chemicals’ release from the products. The fertilizers, which have these starch based encapsulating agents, are safe. They do not harm the health neither in the production, nor in the use phase. In addition, since active agents are better utilized, they would reduce the amount of fertilizers’ production. Native starch, in itself too, is able to decrease the speed of releasing, but if we build ionic function groups into the starch polymers, which are able to bind cations, we can improve the effect. Through the modification of starch, we replaced some of its OH groups in the anhydroglucose monomer unit by the ionic groups of phosphate with chemical reaction. Material and methods The production of starch-phosphates The diammonium hydrogen phosphate (cp = 0.1 g phosphate/ 1 g starch) and the urea were dissolved in water. The pH of this solution (pH of phosphorilation = 9.6) was alkalized with sodium hydroxide, which was later sprayed to the starch. After that this mixture was heat- treated in oven (T = 145 °C; t = 1.5 h). The effect of this treatment was that phosphate groups replaced some of the starch’s OH groups in the anhydroglucose monomer unit. Because of the alkalinity of the solution, two starch polymers could link through the phosphate group, and therefore we could see their polymerization. Also, because of the heat treatment, some of the molecules’ degradation could be observed as well. The qualification of starch-phosphates On the quality of starch derivates, the molecular weight distribution (Mw), solubility (Sol.), and charge density (Ch.d.) were determined. For the analysis, a dilute solution was made from starch derivates. The molecular weight distribution was determined by using size exclusion chromatography (HPSEC) and MALLS laser detector. HPSEC uses a refractive index detector and its signal proportional with the samples’ solubility (RI-area). Charge density was determined by MÜTEK PCD 02, with a particle charge analysator, through colloid titration. This equipment neutralizes the oppositely charged polyelectrolyte solution through titrating the ionic polymer sample. Binding the microelements Binding the microelements to the starch derivatives was performed after the heat treatment. The zinc was added 176 in solid form, the copper in solution form to the starch- phosphate (the starch-phosphate’s temperature was 70 °C). The saturated solution of copper sulphate was sprayed to the starch derivatives during treatment. The solid/solution weight ratio was 1:1–1:0,5. When we added the CuSO4’s solution and the solid ZnSO4*7H2O together, at first we sprayed the CuSO4’s solutions to the 140–145 °C starch-phosphate, than we mixed the solid ZnSO4*7H2O with this compound. The investigation of the microelements’ release The effectiveness of produced fertilizer additives were characterized by the rate of the microelements’ release. The samples were put in bags made from filter cloth, and were dip them into distillated water (1:80 solid/solution). The dissolution was examined at 3 different pH values (pH1 = 5.5; pH2 = 6.5; pH3 = 7.5). It was made 2 measurement series, firstly the pH of distillated water was adjusted just before the dissolutions, than was measured day by day what happened with the pH. In the second series the 3 different pH were adjusted before dissolutions as well, but were maintained in these level every day. The pH levels were controlled with sodium hydroxide and nitric acid solution. In given periods, after stirring the solution, samples were taken, which cubic content was not more than the solution’s 1/100th part. Then the solution samples’ microelements content was analyzed through the complexometric titration and atomic absorption spectrophotometer. Results The parameters of the production and the quality of fertilizers additives are shown in Tables 1 and 2. The micro components were added to the starch- phosphate on the strength of delineated method, than were examined their dissolution in different pH. It is important to compare the micro components dissolution in different pH, because the soil has big buffer capacity in this manner the releasing fertilizer additives affect the pH of the soils less, than the pH of the distillated water which we used in the dissolution tests. The dissolution processes are shown in Figs. 1–8. Table 1: The parameters of the production and the quality of ready fertilizers additives Quality of ready fertilizers additives The parameters of fertilizers production (Binding the microelements) Before binding the microelements After binding the microelementsSample T (°C) CuSO4 solution Solid ZnSO4*7H2O Mw (106Da) Sol. (mV-mL) Ch.d. (meq/g) Ch.d. (meq/g) Zn/5,5/b 70 X 11.5 2.84 0.63 0.48 Zn/6,5/b 70 X 11.5 2.84 0.63 0.48 Zn/7,5/b 70 X 11.5 2.84 0.63 0.48 Cu/5,5/b 70 X 11.5 2.84 0.63 0.53 Cu/6,5/b 70 X 11.5 2.84 0.63 0.53 Cu/7,5/b 70 X 11.5 2.84 0.63 0.53 CuZn/5,5/b 70 X X 11.5 2.84 0.63 0.45 CuZn/6,5/b 70 X X 11.5 2.84 0.63 0.45 CuZn/7,5/b 70 X X 11.5 2.84 0.63 0.45 Zn/5,5/d 70 X 11.5 2.84 0.63 0.48 Zn/6,5/d 70 X 11.5 2.84 0.63 0.48 Zn/7,5/d 70 X 11.5 2.84 0.63 0.48 Cu/5,5/d 70 X 11.5 2.84 0.63 0.53 Cu/6,5/d 70 X 11.5 2.84 0.63 0.53 Cu/7,5/d 70 X 11.5 2.84 0.63 0.53 CuZn/5,5/d 70 X X 11.5 2.84 0.63 0.45 CuZn/6,5/d 70 X X 11.5 2.84 0.63 0.45 CuZn/7,5/d 70 X X 11.5 2.84 0.63 0.45 177 Table 2: The parameters of the dissolution of ready fertilizers additives Dissolution Sample pH pH maintaining Zn/5,5/b 5.5 Before dissolution(b) Zn/6,5/b 6.5 Before dissolution(b) Zn/7,5/b 7.5 Before dissolution(b) Cu/5,5/b 5.5 Before dissolution(b) Cu/6,5/b 6.5 Before dissolution(b) Cu/7,5/b 7.5 Before dissolution(b) CuZn/5,5/b 5.5 Before dissolution(b) CuZn/6,5/b 6.5 Before dissolution(b) CuZn/7,5/b 7.5 Before dissolution(b) Zn/5,5/d 5.5 Day by day (d) Zn/6,5/d 6.5 Day by day (d) Zn/7,5/d 7.5 Day by day (d) Cu/5,5/d 5.5 Day by day (d) Cu/6,5/d 6.5 Day by day (d) Cu/7,5/d 7.5 Day by day (d) CuZn/5,5/d 5.5 Day by day (d) CuZn/6,5/d 6.5 Day by day (d) CuZn/7,5/d 7.5 Day by day (d) 0 10 20 30 40 50 60 70 80 90 100 0 50 100 150 200 250 300 Time of dissolution (h) Z n 2+ d is so lu tio n (% ) 0 1,4 2,8 4,2 5,6 7 8,4 9,8 11,2 12,6 14 C ha ng e of p H Zn/5.5/b Zn/6.5/b Zn/7.5/b pH (5.5) pH (6.5) pH (7.5) Figure 1: The Zn2+ dissolution from starch-phosphate, which contain Zn2+ micro component, in different pH and the change of pH 0 10 20 30 40 50 60 70 80 90 100 0 100 200 300 400 500 Time of dissolution (h) C u 2+ d is so lu tin (% ) 0 1,4 2,8 4,2 5,6 7 8,4 9,8 11,2 12,6 14 C ha ng e of p H Cu/5.5/b Cu/6.5/b Cu/7.5/b pH (5.5) pH (6.5) pH (7.5) Figure 3: The Cu2+ dissolution from starch-phosphate, which contain Cu2+ micro component, in different pH and the change of pH 0 10 20 30 40 50 60 70 80 90 100 0 50 100 150 200 250 300 350 Time of dissolution (h) Z n 2+ d is so lu tio n (% ) 0 1,4 2,8 4,2 5,6 7 8,4 9,8 11,2 12,6 14 C ha ng e of p H Zn/5.5/d Zn/6.5/d Zn/7.5/d pH (5.5) pH (6.5) pH (7.5) Figure 2: The Zn2+ dissolution from starch-phosphate, which contain Zn2+ micro component, in different, but maintained pH and the change of pH 0 10 20 30 40 50 60 70 80 90 100 0 50 100 150 200 250 300 350 Time of dissolution (h) C u 2+ d is so lu tio n (% ) 0 1,4 2,8 4,2 5,6 7 8,4 9,8 11,2 12,6 14 C ha ng e of p H Cu/5.5/d Cu/6.5/d Cu/7.5/d pH (5.5) pH (6.5) pH (7.5) Figure 4: The Cu2+ dissolution from starch-phosphate, which contain Cu2+ micro component, in different, but maintained pH and the change of pH 178 0 10 20 30 40 50 60 70 80 90 100 0 200 400 600 800 1000 Time of dissolution (h) Z n 2+ d is so lu tio n (% ) 0 1,4 2,8 4,2 5,6 7 8,4 9,8 11,2 12,6 14 C ha ng e of p H CuZn-Zn/5.5/b CuZn-Zn/6.5/b CuZn-Zn/7.5/b pH (5.5) pH (6.5) pH (7.5) Figure 5: The Zn2+ dissolution from starch-phosphate, which contain Cu2+ and Zn2+ micro components, in different pH and the change of pH 0 10 20 30 40 50 60 70 80 90 100 0 200 400 600 800 1000 Time of dissolution (h) Z n 2+ d is so lu tio n (% ) 0 1,4 2,8 4,2 5,6 7 8,4 9,8 11,2 12,6 14 C ha ng e of p H CuZn-Zn/5.5/d CuZn-Zn/6.5/d CuZn-Zn/7.5/d pH (5.5) pH (6.5) pH (7.5) Figure 7: The Zn2+ dissolution from starch-phosphate, which contain Cu2+ and Zn2+ micro components, in different, but maintained pH and the change of pH Discussion The results showed, that: ● The value of the solutions pH set in about pH = 4.5, irrespective of the solutions initial pH value. ● If we maintained the pH day by day in the original value, then we can see same phenomena by next day, but when the rate of releasing decreased, the change of pH was not significant. ● The difference of the releasing value in the three different pHs were not considerable, however the difference of the releasing value of the two different micro components was large. ● The dissolution of the zinc was faster either the micro components were separate or together. The stable pH retarded the dissolution, therefore the chance are that the value of the dissolution is more favorable in the soil, comparing to the distillated water what we used in the laboratory tests. 0 10 20 30 40 50 60 70 80 90 100 0 200 400 600 800 1000 Time of dissolution (h) C u2 + di ss ol ut io n (% ) 0 1,4 2,8 4,2 5,6 7 8,4 9,8 11,2 12,6 14 C ha ng e of p H CuZn-Cu/5.5/d CuZn-Cu/6.5/d CuZn-Cu/7.5/d pH (5.5) pH (6.5) pH (7.5) Figure 8: The Cu2+ dissolution from starch-phosphate, which contain Cu2+ and Zn2+ micro components, in different, but maintained pH and the change of pH 0 10 20 30 40 50 60 70 80 90 100 0 200 400 600 800 1000 Time of dissolution (h) C u 2+ d is so lu tio n (% ) 0 1,4 2,8 4,2 5,6 7 8,4 9,8 11,2 12,6 14 C ha ng e of p H CuZn-Cu/5.5/b CuZn-Cu/6.5/b CuZn-Cu/7.5/b pH (5.5) pH (6.5) pH (7.5) Figure 6: The Cu2+ dissolution from starch-phosphate, which contain Cu2+ and Zn2+ micro components, in different pH and the change of pH SYMBOLS cp: g phosphate salt/ in 1g starch T/t: temperature of heat treatment/ duration T: temperature of the microelement’s bonding Mw: molecular weight distribution Sol.: solubility Ch.d.: charge density REFERENCES 1. J. DENCS, G. NOS, B. DENCS, G. MARTON: Proceedings of the 1st World Conference on Biomass for Energy and Industry, Vol. II 1024 (2001). 2. M. MEICZINGER, G. MARTON, J. DENCS, B. DENCS: Investigation of Reaction Occurring at Starch Phosphorylation – Industrial and Engineering Chemistry Research. 45, 2005, 9581–9585. 179 3. T. A. TARI, R. S. SINGHAL: Starch-Based Spherical Aggregates: Stability of a Model Flavouring Compound, Vanillin Entrapped Therein – Carbohydrate Polymers, 50, 2002, 417–421. 4. A. R. KULKARNI, K. S. SOPPIMATH,. T. M. AMINABHAVI, A. M. DAVE, M. H. MEHTA: Urea- Formaldehyde Crosslinked-Starch and Guar Gum Matrices for Encapsulation of Natural Liquid Pesticide [Azadirachta Indica a. Juss. (Neem) Seed Oil]: Swelling and Release Kinetics – Journal of Applied Polymer Science, 73, 1999, 2437–2446. 5. B. LENAERST, I. MOUSSA, Y. DUMOULIN, F. MEBSOUT, F. CHOUINARD, P. SZABO, M. A. MATEESCU, L. CARTILIER, R. MARCHESSAULT: Cross-Linked High Amylose Starch for Controlled Release of Drugs: Recent Advances – Journal of Controlled Release, 53, 1998, 225–234. 6. C. F. WILLIAMS, S. D. NELSON, T. J. GISH: Release Rate and Leaching of Starch-Encapsulated Atrazine in a Calcareous Soil – Soil Science Society of America Journal, 63, 1999, 425–432. << /ASCII85EncodePages false /AllowTransparency false /AutoPositionEPSFiles true /AutoRotatePages /None /Binding /Left /CalGrayProfile (Dot Gain 20%) /CalRGBProfile (sRGB IEC61966-2.1) /CalCMYKProfile (U.S. Web Coated \050SWOP\051 v2) /sRGBProfile (sRGB IEC61966-2.1) /CannotEmbedFontPolicy /Error /CompatibilityLevel 1.4 /CompressObjects /Tags /CompressPages true /ConvertImagesToIndexed true /PassThroughJPEGImages true /CreateJobTicket false /DefaultRenderingIntent /Default /DetectBlends true /DetectCurves 0.0000 /ColorConversionStrategy /CMYK /DoThumbnails false /EmbedAllFonts true /EmbedOpenType false /ParseICCProfilesInComments true /EmbedJobOptions true /DSCReportingLevel 0 /EmitDSCWarnings false /EndPage -1 /ImageMemory 1048576 /LockDistillerParams false /MaxSubsetPct 100 /Optimize true /OPM 1 /ParseDSCComments true /ParseDSCCommentsForDocInfo true /PreserveCopyPage true /PreserveDICMYKValues true /PreserveEPSInfo true /PreserveFlatness true /PreserveHalftoneInfo false /PreserveOPIComments true /PreserveOverprintSettings true /StartPage 1 /SubsetFonts true /TransferFunctionInfo /Apply /UCRandBGInfo /Preserve /UsePrologue false /ColorSettingsFile () /AlwaysEmbed [ true ] /NeverEmbed [ true ] /AntiAliasColorImages false /CropColorImages true /ColorImageMinResolution 300 /ColorImageMinResolutionPolicy /OK /DownsampleColorImages true /ColorImageDownsampleType /Bicubic /ColorImageResolution 300 /ColorImageDepth -1 /ColorImageMinDownsampleDepth 1 /ColorImageDownsampleThreshold 1.50000 /EncodeColorImages true /ColorImageFilter /DCTEncode /AutoFilterColorImages true /ColorImageAutoFilterStrategy /JPEG /ColorACSImageDict << /QFactor 0.15 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> /ColorImageDict << /QFactor 0.15 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> /JPEG2000ColorACSImageDict << /TileWidth 256 /TileHeight 256 /Quality 30 >> /JPEG2000ColorImageDict << /TileWidth 256 /TileHeight 256 /Quality 30 >> /AntiAliasGrayImages false /CropGrayImages true /GrayImageMinResolution 300 /GrayImageMinResolutionPolicy /OK /DownsampleGrayImages true /GrayImageDownsampleType /Bicubic /GrayImageResolution 300 /GrayImageDepth -1 /GrayImageMinDownsampleDepth 2 /GrayImageDownsampleThreshold 1.50000 /EncodeGrayImages true /GrayImageFilter /DCTEncode /AutoFilterGrayImages true /GrayImageAutoFilterStrategy /JPEG /GrayACSImageDict << /QFactor 0.15 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> /GrayImageDict << /QFactor 0.15 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> /JPEG2000GrayACSImageDict << /TileWidth 256 /TileHeight 256 /Quality 30 >> /JPEG2000GrayImageDict << /TileWidth 256 /TileHeight 256 /Quality 30 >> /AntiAliasMonoImages false /CropMonoImages true /MonoImageMinResolution 1200 /MonoImageMinResolutionPolicy /OK /DownsampleMonoImages true /MonoImageDownsampleType /Bicubic /MonoImageResolution 1200 /MonoImageDepth -1 /MonoImageDownsampleThreshold 1.50000 /EncodeMonoImages true /MonoImageFilter /CCITTFaxEncode /MonoImageDict << /K -1 >> /AllowPSXObjects false /CheckCompliance [ /None ] /PDFX1aCheck false /PDFX3Check false /PDFXCompliantPDFOnly false /PDFXNoTrimBoxError true /PDFXTrimBoxToMediaBoxOffset [ 0.00000 0.00000 0.00000 0.00000 ] /PDFXSetBleedBoxToMediaBox true /PDFXBleedBoxToTrimBoxOffset [ 0.00000 0.00000 0.00000 0.00000 ] /PDFXOutputIntentProfile () /PDFXOutputConditionIdentifier () /PDFXOutputCondition () /PDFXRegistryName () /PDFXTrapped /False /CreateJDFFile false /Description << /ARA /BGR /CHS /CHT /CZE /DAN /DEU /ESP /ETI /FRA /GRE /HEB /HRV (Za stvaranje Adobe PDF dokumenata najpogodnijih za visokokvalitetni ispis prije tiskanja koristite ove postavke. 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