SYNTHESIS OF SOME ADHESIVES (GUMS) FROM CARBOHYDRATES AND STUDIES OF EFFECT OF ADDITION OF SOME CATIONS ON VISCOSITY.

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1 African Journal of Science and Research,2016,(5)2:29-34 ISSN: Available Online: SYNTHESIS OF SOME ADHESIVES (GUMS) FROM CARBOHYDRATES AND STUDIES OF EFFECT OF ADDITION OF SOME CATIONS ON VISCOSITY. Received:16,Mar,2016 Fathia Mohammed Ibrahim 1, Mubark Elsayed Osman 2 and Ibrahim Mohammed Ahmed 2 National Center for Research,Institute of Engineering Research and Materials Technology, Sudan. 2) Department of Chemistry, Faculty of Science, University of Khartoum, Sudan. Fatmhd25@yahoo.com Accepted:03,Apr,2016 Abstract The study aimed to prepare some synthetic adhesives (gums) from carbohydrate, by addition of the formite salts (sodium, potassium and ammonium formite salt) to monosaccharide (e.g., glucose, fructose and galactose) and disaccharide (e.g., sucrose, maltose and lactose), then compare some of their physical characteristic with gum Arabic. The synthetic adhesives may be used for industrial purposes other than food and pharmaceutical products. The study also aimed to exchange sodium and potassium ions of prepared adhesives (gums) with calcium, magnesium and iron ions and determine the impact of ions on viscosity. Formite salt was prepared by bubbling excess gaseous carbon monoxide into cold solutions of sodium hydroxide and potassium hydroxide separately as shown. Keywords: Gums, Adhesives, viscosity, Pharmaceutical industries. INTRODUCTION This study is devoted to produce new synthetic adhesives (gums) and compare it with Gum Arabic, by measuring physical properties such as viscosity, to save Gum Arabic for food and Pharmaceutical industries, because gum Arabic is widely used in industry as an emulsifying and/or a thickening agent. Gum Arabic is organic adhesive produced from acacia Senegal. It mainly produced in sub- desert regions in Africa including countries such as Sudan, Senegal, Mauritania, Cameroon, Mali and Chad. Which is obtained from the fruit, trunk, or branches of trees spontaneously or after mechanical injury of plant by incision of bark or by removal of branches, or after invasion by bacteria or fungi [1-3] The classification of gum composed of the main categories: 1. Natural gums: those found in the nature, e.g., gum Arabic, guar gum, etc. 2. Modified natural or semi synthetic gums, those based on chemical modification of gums, (e.g., cellulose derivatives such as carboxymethyl cellulose, propylene glycol alginate and starch derivatives, e.g., carboxymethyl starch and hydroxyl ethyl starch, 3. Synthetic gums, those are prepared by chemical synthesis e.g., polyvinyl alchohol, polyacryl amide, etc. Gums are considered to be carbohydrates, which it exists in nature as a neutral or slightly acidic (D-glucuronic) salt of complex polysaccharide containing calcium, magnesium, potassium and sodium and containing a number of monosaccharide (hexoses, pentoses) units which are often esterifies in highly branched structures [1-5], [6] Therefore the complete hydrolysis of gum arabic yields the four basic sugar constituents, D- galactose, L- rhamnose, L-arabinose, and D-glucuronic acid. [1-3] Gums are hydrophilic, with high molecular weight, and have colloidal properties. In appropriate solvents, or swelling agents, gums produce gels or highly viscous solutions depending on the concentration employed. [1-3], [6], [7] The most fundamental property of a gum therefore is its water solubility and high viscosity in aqueous dispersions. It is readily soluble to give relatively low viscosity newtonian solutions even at high concentrations (20-30 % wt/wt), [8] therefore, gum has a wide application in industry as thickening agents or emulsion stabilizers. [1], [3], [9]. especially, in area of feed, textile and pharmaceutical industries. In food products it serves as stabilizer, emulsifier and as binding agent. [10] Gum arabic is considered to be a mixture of polysaccharides and glycoproteins which it gives the properties of glue, adhesive and binder. [11] Adhesives and glues are substances that adhere or bond two items together at their surfaces. There are two types of adhesives; natural and synthetic. [12] Natural adhesives come from animal and vegetable sources. A major type of natural adhesives is animal glues (or organic adhesives) made from collagen; a protein found in skin, bone, intestine, and sinew and also come from fish. [12], [13] Organic adhesives are derived from blood albumen and casein (a protein available in milk). Animal glues are used in wood industries and paint. [12-15] Another type of natural adhesives are vegetable adhesives which include starches and dextrins; derived from corn, wheat, potatoes, and rice and used for bonding paper, wood, and textiles. [16] In addition, adhesives from vegetable sources include natural gums, agar, algin resins, and starch derivatives. [17] They are commonly used for sizing paper and textiles and for sealing (envelopes) and manufacturing paper goods and in stamps. [17] Gum Arabic glues have certain qualities that make them desirable; they are easy to prepare, light in color, odorless, and very stable. [16]. The adhesive strength of the gum Arabic can be improved by the addition of certain metal salts such as calcium nitrate and aluminum sulfate. [16] However, these glues also have shortcomings. For instance, when heated in water or subjected to high temperatures for too long time, gum Arabic is degraded; resulting in decrease in viscosity and loss of adhesive strength. [16] In the past, adhesive for bonding aluminum foil to paper have been prepared from gum Arabic solution modified with small amount of tartaric or a similar acid. [16] Gum Arabic also employed together with sodium hydroxide as an adhesive agent for paper products. [1], [3] Synthetic adhesives, used either alone or as modifiers of natural adhesives, have a greater range of applications than the natural products. [16] Most of them are polymers (huge molecules incorporating a large numbers of simple molecules) which form strong chains and link surfaces in a strong bond. [16] Thermosetting adhesives are used in such structural function as bonding metallic parts of aircrafts and space vehicles. Examples of thermosetting

2 30 Fathia Mohammed Ibrahim et.al adhesives include phenol formaldehyde resin, used in electric insulators and plastic wear. [16] Urea-formaldehyde resin, used in plywood and particle board. [17] Thermoplastic resins, for example, cellulose acetate, ethylene-vinyl acetate and polyamide (nylon), are used for bonding wood, glass, rubber, metal, and paper products. [16] MATERIALS AND METHOD Materials Sodium hydroxide, potassium hydroxide, sulphuric acid, formic acid, magnesium chloride, calcium chloride, hydrochloric acid, distilled water, galactose, glucose, fructose, lactose, maltose were used, as suggested by BDH, without further purification. Method Synthesis of sodium, potassium and ammonium salts of glucose: 3.4g of glucose were dissolved in distilled water and then filtered off. The resultant clear solution was added to filtered solution containing 1g of (Na / K / NH4) formite, separately. The solution (mixture) was left few days; viscous solution was obtained. The same experiment was repeated using fructose, galactose, sucrose, maltose and lactose instead of glucose. The viscosity of the prepared formite salts(gums) were measured. RESULTS AND DISCUSSIONS Gums are complex mixture of saccharides, containing a number of neutral sugars, acid, and salts of (calcium, potassium, sodium, and magnesium). It is built upon backbone of D-galactose units with side chains of D-glururonic acid with L-rhamnaose or L-arabinose terminal units. Gum Arabic is an organic adhesive and is characterized by their viscous properties; viscosity considered as most important analytical parameter. Gum Arabic is almost unique among commercially important gums. It has well-established characteristics in terms of solubility, color, odor, taste, emulsification and film formation. Moreover, it has low viscosity when it was compared with the liner polysaccharides, e.g., locust bean gum and guar gum. These properties are very important to many industries including confection, beverages, encapsulated flavors, pharmaceuticals, cosmetics, printing, adhesives, inks, textiles, and other applications. Since gums, the natural adhesives are complex matrix of sodium, potassium, magnesium, and calcium salts of carbohydrates in nature (composition), then it seems to evaluate the adhesive properties imparted to the resultant salts when monosacharides, disaccharides, oligosaccharides, and polysaccharides are treated with the formite salts. The viscosities of the synthetic adhesives (gums) have been measured. The results are given in Tables The results showed that the viscosity of the prepared formite salts (gums) measured in cp (centipoises) were as follows: Glucose-NaCHO ; Glucose-KCHO ; Glucose- NH4CHO ; Fructose- NaCHO, ; Fructose- KCHO ; Fructose- NH4CHO, ; Glactose-NaCHO ; Glactose-KCHO 343.5; Glactose- NH4CHO ; Sucrose-NaCHO ; Sucrose-KCHO309.15; Sucrose- NH4CHO ; lactose-na-cho ; Lactose- KCHO2475.0; Lactose-NH4CHO ; Maltose-Na-CHO ; Maltose-KCHO ; Maltose- NH4CHO 515.0; and Maltose- NaCHO /resin , for Acacia seyal sample the viscosity is and for Acacia sengal 100, respectively. After exchanging sodium and potassium ions of prepared adhesives with calcium, magnesium, iron, copper and aluminum ions, the viscosity was measured and the results indicated that the addition of monovalent increases the viscosity while the addition of divalent ion renders the viscosity 0.00 as all formites turned to be powder. Based of these findings the viscosity of gum Arabic seems to be attributed to monovalent ions and the hardness to divalent ions. The presence of metal ions suggests that gums may be considered as salts of the constituent saccharides. Since in present work a method have been developed (established) to convert sugars into the corresponding sodium, potassium, or ammonium salts, then the availability of such products makes it possible to study their properties and evaluate their correspondence and relevance to these imparted by gums in general. Sodium, potassium, ammonium, magnesium, calcium, iron, zinc, and copper salts of glucose, fructose, galactose, maltose, lactose, and sucrose have been prepared by mixing the given sugars with the soluble sodium, potassium, and ammonium formites. The salts of magnesium, calcium, iron, zinc, and copper have been obtained by mixing soluble salts solutions (soluble chloride, nitrate or sulphate salts) of these elements with equimolar amounts of the soluble salts of sodium, potassium, or ammonium formite as equations suggest: The magnesium and aluminium salts of sugars were found to be sparingly soluble; addition of magnesium chloride (MgCl2) and aluminium sulphate (Al2 (SO4) 3) solutions to soluble formite salts results in immediate (instantaneous) precipitation of the corresponding sugar salts. The calcium salts are relatively more soluble. It may be concluded on the basis of this behavior (observation) that the presence of magnesium, calcium and aluminium ions is mainly to give (impart) hardness (strength) to gums and avoid jelly or semi-sold forms. The addition of monovalent metal ions (Na, K, NH4 + ) was found that to increase the viscosity of sugar salts. But the addition of divalent metal ions was found that to decrease the viscosity of sugar salts. The principal property of gums is viscosity. The potassium salts of all sugars in general and of galactose in particular were found to be the most viscous ones followed by the sodium and ammonium salts. Both viscosity and solubility of gums, therefore, seem to be very department on the occurrence of such ions K, + NH4, + Na +. T able( of sodium salt of glucose s(skt) s/n

3 African Journal of Science and Research, 2016,(5)2: Table(2) of potassium salt of glucose s(skt) s/n Table(3) of ammonium salt of glucose s(skt) s/n Tabe(4) of sodium salt of fructose s(skt) s/n Table(5) of potassium salt of fructose s(skt) s/n Table (6) of ammonium salt of fructose s(skt) s/n Table(7) of sodium salt of galactose s(skt) s/n Table(8) of potassium salt of galactose s(skt) s/n Table(9) of ammonium salt of galactose s(skt) s/n

4 32 Fathia Mohammed Ibrahim et.al Table(10) of sodium salt of galactose/resin s(skt) s/n Table(1 of sodium salt of sucrose s(skt) s/n Table(12) of potassium salt of sucrose s(skt) s/n Table(13) of ammonium salt of sucrose s(skt) s/n Table(14) of sodium salt of maltose s(skt) s/n Table(15) of potassium salt of maltose s(skt) s/n Table(16) of ammonium salt of maltose s(skt) s/n Table(17) of sodium salt of maltose/resin s(skt) s/n

5 African Journal of Science and Research, 2016,(5)2: Table(18) of sodium salt of lactose s(skt) s/n Table(19) of potassium salt of lactose Table(22) of sodium salt of sucrose/resin s(skt) s/n s(skt) s/n Table(20) of ammonium salt of lactose Table(2 of sodium salt of sucrose/fe s(skt) s/n s(skt) s/n Fig(assemble used in generation of carbon monoxide and preparation of formite salts CONCLUSION This study is devoted to produce new synthetic adhesives (gums). The viscosity of synthetic adhesives (gums) was measured and the results indicated that the addition of monovalent ions increases the viscosity while the addition of divalent ions renders the viscosity 0.00 as all formites turned to be powder. Based of these findings the viscosity of gum Arabic seems to be attributed to monovalent ions and the hardness to divalent ions. The principal property of gums is viscosity. The potassium salts of all sugars in general and of galactose in particular were found to be the most viscous ones followed by the sodium and ammonium salts. Both viscosity and solubility of gums, therefore, seem to be very department on the occurrence of such ions K, + NH4, + Na +. The study showed that Na, K, Mg and Ca are the main determinations of the gum viscosity. Acknowledgment First and foremost, I am offering my thanks, obedience and gratitude to Allah who helped me and gave me the strength to achieve this work. I would like to thank the National Center of Research and

6 34 Fathia Mohammed Ibrahim et.al University of Khartoum, Faculty of science, Department of Chemistry for technical help and for supporting this study. The major findings: 1. The addition of monovalent metal ions (Na, K, NH4 + ) was found that to increase the viscosity of sugar salts (gums), so the viscosity of gum Arabic seems to be attributed to monovalent ions 2. But the addition of divalent metal ions was found that to decrease the viscosity of sugar salts, so the hardness of gum Arabic seems to be attributed by to divalent ions (Ca ++, Mg ++ ). 3. The potassium salts of all sugars in general and of galactose in particular were found to be the most viscous ones followed by the sodium and ammonium salts. Both viscosity and solubility of gums, therefore, seem to be very department on the occurrence of such ions K, + NH4, + Na +. References 1. Glicksman M. Gum Technology in the Food Industry. New York: Academic Press; J.K.N., Jones and F. Smith, Advances in Carbohydrate Chem. 4, p (1949). 3. Glicksman, M., and Schachat, R.E., (Gum arabic in Industrial Gums) R. L., Whistler. Ed). Academic Press, New York. 1959, Pp Finzi, A, C, Charies, D, C, Breemen, N, V, Canopy tree-soil interactions within temperate forest: Species effects on ph and cations. Ecol. Appl, 8: Glicksman, M and sand, R. E Industrial Gum, 2 nd ed, Wistle,r Academic Press Howes, F. N.; Vegetable Gum and Resin; Chronica Botanic, Walthan, Massachusetts, Stoloff, L.; Adv. Carbohydr. Chem. Biochemistry, 1958, 13, C. Sanchez, D. Renard, P. Robert, C. Schmitt and J. Lefebvre, Structure and rheological properties of acacia gum dispersions, Food Hydrocolloids 16 (2002) J.J.W. Coppen, FAO, Rome (1995), Gums, Resins and Lactexes of plant origin. 10.Verbeken, D.; Dierckx, S. & Dewettinck. (2003). Exudate gums: Occurrence, production, and applications. Applied Microbiology and Biotechnology, Vol.63, No. 1, (November 2003), pp , ISSN: FAO, Rome (1990). Food and Nutrition paper 49: html Partik Spielman. Gluing Clamping: Awood workers handbook Sterling Publishing, BN word.com./ newsite/ Renortfassav/ Science/physical / Adhesives W.H.Wood U.S. Patent 2, 589, 313 (1952); Chem. Abstr. 46, 6024 (1952).