METHOD OF PREPARATION OF PRODUCTS WHICH ABSORB WATER INTERMOLECULARLY

Abstract: A method of crosslinking polystyrene polymers and co-polymers for the formation of macroplegmatic materials of an Mc 30,000 to 50,000 is described. The materials forming an insoluble gel which is shaped in an extruder to 3 to 5 cm pieces and is subject to sulphonation with dense sulphuric acid, with oleum sulphuric acid with sulphur trioxide and with chlorosulphonic acid, and the introduction of sulphonic groups to a high density and with the introduction of nitric group and with the introduction of carboxylic group with the copolymer styrene-acrylonitrile. The chlorosulfonic group promotes sulphonation and crosslinking with the formation of bridges with the sulfone group which is controlled with a 10-20 % of acetic acid present as regulator and an insoluble volume of gel is formed which following drainage of the solvent and after remaining to ripen for 4-7 hours it is treated with ethanol or propanol to extract the unreacted chlorosulphonic acid then is neutralised with sodium or potassium hydroxide subjected to an extruder for the preparation of 3-5 cm products. Following neutralisation and shrinkage to a 10 % water content and the products produced are deodorised at a temperature of 160 DEG C under vacuum and are converted to materials which absorb water inside their molecules up to 300 times their weight; having an inorganic content of 72-75 % they exhibit a high degree of stability in the ground, they do not degrade and can be used indefinitely for water absorption-release so that they operate as fertility promoters to any type of soil leading to an increase of green growth, and to the planting of trees and forests and to advance food production.

Description: METHOD OF PREPARATION OF PRODUCTS WHICH ABSORB WATER INTERMOLECULARLY Subject of the Invention The invention refers to a method for the preparation of products which are defined by a polymer of a macroplegmatic structure which includes ionic groups at a large density and from which products are derived which absorb intermolecularly, i.e inside their molecules , large quantities of water, up to 300 times their weight and which exhibit a high ability in the ground to promote soil fertility and cover water consumption needs, offering a reduction of water consumption of up to 12 times. Objective of the Invention Saving in water consumption is at present a principal subject of global importance , whereas the phenomenon of desertification that has arisen in several areas of the planet constitutes a primary source of global concern associated with the survival of the planet. Agriculture production in synchronisation with the needs of the over-populated planet in what concerns the satisfaction of food demand , whereas the so-called green revolution has several weaknesses, leads to enforcement of nature and to soil erosion. The principal cause for all that is covering the needs of water , in a manner that serves but does not erode nature. This problem is severely aggravated at present, as the water balance is broken , the sea starts covering large areas of chores reducing the availability of fertile land and leading to a new geographical status of equilibrium between the sea and the land. It is hence a primary need to introduce new principles in water usage leading to saving associated both with human consumption as well as with the use of water for agricultural needs, where solutions which offer maximum economy in water usage must be introduced. Development of the Invention The invention describes products which cover the needs of soil in water leading to water saving in the Earth, the Nature and the Agriculture , thus the invention provides concern of water economy in these uses. The products which absorb water inside their molecules which are subject of this invention, are produced following a special crosslinking processing of polymers towards a stable macroplegmatic structure; such polymers contain active aromatic rings such as polystyrene .hydrogenated SBR, styrene- acrylonitrile and all their co-polymers. As crosslinking agents the dibenzo-X- dimethylbenzene and the sulphonic -SO2 .radical, are used. The processing is promoted in solutions of the polymer on chlorinated hydrocarbon solvents , and in molten phases of the polymers at high temperatures. The macroplegmatic polymers as produced in the form of a gel are practically insoluble and must be subject to processing for the introduction of the ionic groups and for this reason , the macroplegmatic polymers are subject to a suitable shaping in the special cutting equipment where the gel formed is entered in an array of tubes of a length of one meter and of diameter of two to four centimetres where the gel is cut longitudinally and at its end transversely in three to four centimetre pieces so that discrete particles of dimensions of three by four centimetres are produced. In this form ,the material prepared suspended in the solvent is subsequently subject to a sulfonation for the introduction of high density sulfonic groups Strong agents of sulphonation are utilised for the introduction of sulfonic groups to the suspension of the polymer , such as chlorosulphonic acid in a quantity of 1 ,5-2 Moll to the aromatic rings or sulphur trioxide in a similar quantity or oleum sulphuric acid according to the sulphur trioxide contained .Sulphonation is fast and efficient as also is the introduction of nitric groups and the introduction of carboxylic groups with the use of the co-polymer styrene-acrylonitrile as hydrolysis of the -CN group contained occurs , with a final shaping of spherical products suspended in the solvent of the sulphonation process The product is then removed the solvent is decanted and it is washed with ethyl or propyl alcohol to collect the unreacted chlorosulphonic acid , then is neutralised in 30% sodium or potassium hydroxide in a recalculated quantity and having adsorbed water to a degree of 30-50 times its weight ,it is then introduced to a tank which contains a 15- 25% sodium chloride solution where the polymer shrinks in terms of water content to about 10%.The product can be also dehydrated by passing through a 20V electrical field .Finally ,the product is heated under vacuum up to 160oC degrees and is fully dehydrated and freed from the solvent ,so that it becomes a marketable product able to absorb water up to 150-300 times its weight. It has the form of small spheres or leaves depending on the cutting process in the extruder In a different preparation process to the 10-30% solution of polymer chlorosulfonic acid is added as a 30% solution in a quantity of 2-2,2 Mol to the benzene rings The solution contains 12% acetic acid as an inhibitor of the control of introduction of crosslinking with sulphone groups. As the sulphonation reaction progresses, as measured by the release of hydrogen chloride, an insoluble gel is formed by the macroplegmatic evolution of the polymer with the formation of sulphone bridges. The gel as it being formed which lasts 4-6 hrs ,it is removed the solvent which constitutes its own layer and is removed by draining ; the gel is then washed with ethanol or propanol to react the unreacted chlorosulfonic acid and the solution is drained ; finally the pure gel which is into a non stirrable volume is neutralised with calculated amounts of sodium or potasium hydroxide. Then it is strained and passed to an extruder where it is cut to the desired size and shape of particles and is then subject to complete neutralisation to size reduction and to deodorisation and becomes a marketable product as previously described. As already mentioned, hydrogen chloride is formed during the sulphonation reaction with chorosulphonic acid This is absorbed in a sulphur trioxide solution in chlorinated solvents with the formation of chlorosulphonic acid and the procedure mentioned is combined with the preparation of chlorosulphonic acid with delivery of sulphur trioxide to a solution. Furthermore, a process has been developed involving phase dispersion conditions during crosslinking of the polymer with the 1 ,4-dichloromethyl-2,5- dimethylbenzene between the solvent 1 ,2 dichloroethane and an equal volume of dense sulphuric acid in a constant temperature around 50oC during which small spheres are formed. In the sequel sulphuric acid is added to the spheres formed with sulphonation promotion with temperature rise up to 80oC ,or 1 ,5-2.0 Mol of chlorosulphonic acid added at a normal temperature along with a 12% acetic acid solution to the solvent used and, following three hours of stirring the sulphonation is complete and the product is collected , strained and neutralised, shrunk and deodorised .Finally a high specification product is received regarding the colour and spherical shape With the above process involving processing sulphuric acid and chlorosulphonic acid .straining gives a mixture of solvent and sulphuric acid of a volume about four cubic meters per ton of product which must be distilled for the collection of solvent and to dispose or use of sulphuric acid in a pure quality for recycling The inventor has also invented and developed products that absorb intermolecularly water following simple immersion of inflated polystyrene into oleum sulphuric acid of a content of trioxide 20,30 and 65% with which the polymer is decayed by the sulphur trioxide and large spheres of great uniformity are formed They exhibit a degree of inflation of 40 to 70 which depends on the degree of inflation of polystyrene These materials .following 12 hours maturing, .are collected and washed with water This product is not neutralised but delivered in acidic form and constitutes a product which promotes in the soil water economy and fertility In all the above the process of our invention is described in the form of materials which absorb water intermolecularly and promote fertility to the ground These products have been studied in terms of activity and the following have been observed: a) With the addition of these products to the soil , the growth of trees and forests is possible with full survival and acceleration of growth as water economy in the order of 12 is achieved sufficient for 120 days of biological activity b) The growth of fruit bearing trees is promoted with an acceleration of growth in the order of 30 to 40% , a biomass production increase of 30 to 50% and a doubling of fruit production c) Soil fertility is promoted in problematic .sterile and mountain areas as these materials offer water economy to the ground .and help the growth of green and the development of soil biological activity These materials which contain water intermolecularly which does not evaporate nor is leaked in the ground but kept as in a tank for covering the water needs of plants and of trees, consist of inorganic material to the extent of 72 to 75% where the polymer is only the shell and accounts for only 25- 28% by weight .Thus .these materials have maximum stability in soil where they not degrade biologically not are they altered in terms of composition. Thus the products of the invention can operate for indefinite long period of time by absorbing/delivering water in the soil . As a consequence , the products of the invention analysed and described above constitute means of the highest value and utility in maintaining the natural operation, the promotion of natural growth and the production of food production in a sustained manner as they promote soil fertility independently of the quality of the soil and in every soil under any conditions. Example No 1 a. Preparation of the crosslinking agent The mixture of reactants for the preparation of the crosslinking agent 2,5- dichloromethyl -1 ,4-dimethylbenzene , are : 246.2 ml of o-xylene , 2370 ml of a 37% formaldeyde solution in a 5 litres of hydrochloric acid solution 35% ( Molar ratio 1 :6;12)The mixture is brought to a 10 litres glass reactor heated to 95oC and stirred for 5 hours ; it then remains at normal temperature for 12 hours forming crystals of the crosslinking agent which is collected by filtration (205 grams) Furthermore 400 ml of hydrogen chloride are added to the solution. Following heating under stirring for 5 hours and then cooling a new quantity of the crosslinking agent settles(152 grams )with 91% yield The product is then recrystallised in alcohol and form a pure product with a melting point of 125oC b. Preparation of the macroplegmatic gel In a pilot unit featuring a 200 litres dissolution tank a 2 k.m. sulphonation reactor and other parts which will be described in the following , 30 kg of polystyrene solution in 100 litres of chlorinated solvent is formed : 300 gram of crosslinking agent are added to the solution under stirring conditions . followed by a dense sulphuric acid catalyst until a grit is formed (5 cm of catalyst 20 minutes resistance time) the macroplegmatic gel formed is extracted and cut into 4-5 cm pieces Example No 2 In the pilot plant of example No 1 , 20kgs of polystyrene solution is formed in 100 litres of solvent ; to this 200 grams of crosslinking agent are added and then sulphuric acid as catalyst until a grit is formed (6 ml, 24 minutes) The mixture is transferred to the extruder before the formation of the gel .the extruder being defined by a system of 3 cm 1 meter long tubes featuring a space for the draining of the mixture. The solution is converted to macroplegmatic and then compressed in the tube system towards the outlet where a cutting system operates for forming 3-5 cm particles The small particles and the solvent are brought to the sulphonation reactor where 65% oleum sulphuric acid is added as a 30% solution in the chlorinated solvent at quantity so that the sulphur trioxide to contain 2.2 Moles/Mole of benzene units. The stirring lasts for 2 hours following the end of sulphonation and in the sequel .the product is extracted and brought to a perforated container for staining of the solvent .In the sequel it is passed with the perforated container to be washed with propanol to extract the unreacted chlorosulphonic acid and then is brought to a neutralisation tank with 30% potassium hydroxide; then is immersed in 20 % sodium chloride for shrinkage and it is passed with water content of 12% to a container for heating to 160oC with stirring and under vacuum , following which 80 kgs of product are received in the form of irregular small spheres ; in technical terms it is a light product with a degree of inflation in water in the order of 225 and with a composition of 75% inorganic and 25% organic , with a practical yield of 100% Example No 3 A 200 litres 30% polystyrene solution in 1 ,2 dichloroethane as solvent which contain 12% acetic acid is brought to the sulphonation reactor where chlorosulphonic acid is added 2-2,2 Moles/Mole of benzene units with stirring as a 25% solution The reaction of sulphonation and formation of grosslinks with sulphone radicals advance rapidly and this is measured by the release of hydrogen chloride and the gradual release of the solvent Finally a gel is formed which is insoluble and after 4 hrs of ripening the solvent is decanted ;then to the gel is added propanol to extract the unreacted chlorosulphonic acid , then it is subjected to partial neutralisation with 30% potassium hydroxide. It is taking to the extruder and cut to pieces of 3 to 5 cm is completely neutralised and then after shrinkage treatment by passing through an electrical field of 20V .Finally is taking for deodorisation by heating at 160oC under vacuum and stirring and the product obtained is of brilland colour with a degree of inflation 258 and with a composition 23% organic, 77% inorganic The hydrogen chloride released is passed to a sulphur trioxide solution in 1 ,2 dichroloethane where it is absorbed to form chlorosulphonic acid The exploitation of the hydrogen chloride produced simplifies the transfer of the reactants by passing to a sulphur trioxide solution and formation of chlorosulphonic acid during the reaction with continuous recycling Example No 4 20 gr. of the 50-50% styrenbe -acrylonitrile copolymer are dissolved in the solution reactor in 100 litres of pure 1 ,2 dichloroethane .100 grans of the crosslinking agent are added to the solution and then sulphuric acid is also added until a grit is formed. The mixture is brought to an extruder where .a gel is formed and with the exertion of pressure it is promoted to the tubes so that the material is cut into 4 to 5 centimetres pieces. The pieces and the solvent are brought to the sulphonation reactor where 65% of oleum sulphuric acid as a 25% solution and at quantity of 2 Moles/Mole of benzene nuclei Following a reaction and stirring for 5 hours the product is removal .strained neutralised and passed to a 20 V electric field and finally ,with a 5% water content it is heated at 160°C with stirring and with the application of vacuum and is converted into a high specification product with a degree of inflation in water of 185 This product has two ionic groups , a sulphonic one and a carboxylic one from the hydrolysis of acrylonitrile Example No 5 20 gr. of fully hydrogenated SBR (styrene 4o%) are brought to a reactor in 100 litres of 1 ,2 dichloroethane Following dissolution , 80 gr. of crosslinking agent are added and with the addition of sulphuric acid as a catalyst ,the mixture is passed to the extruder where it is transformed to a macroplegmatic material. The 4 to 5 centimetres pieces finally produced and the solvent are brought to the sulphonation reactor where 65% oleum sulphuric acid is added as a 25% solution in a quantity of 2 Mole SO3 per Mol of benzene nuclei Following reaction and stirring for four hours , the product is removed , trained , strained , neutralised and shrunk in a 20 V electric field and following heating at 160 oC under stirring and vacuum a high specification product is received with an inflatability ratio of 120 Example No 6 Inflated polystyrene is brought to 65% oleum sulphuric acid and left to be eroded by the acid .Sulphonated products are formed in the form of sizeable spheres in a normal shape and in order. These, following a residence time of 12 hours are collected , washed with water and form a high added value and usability products. They adsorb water up to 40-70 times their weight , depending on the degree of inflation of the polystyrene and are offered as products for agricultural use in the acidic form

Claims: CLAIMS Following the presentation of the invention it is claimed: 1. Method of preparation of macroplegmatic products following crosslinking of polymers which contain aromatic ring such as polystyrene and its co- polymers by formation of an insoluble gel following processing of the polymers in solution in chlorinated solvents where the crosslinking agents are 2,5-dichloromethyl -1 ,4-dimethylbenzene and sulphur dioxide, and following - the insoluble macroplegmatic gel which is formed before the sulphonation with the agent 2,5-dichloromethyl-1 ,4 dimethylbenzene ,is shaped in an extruder towards products of dimensions 3 to 5 centimetres and then sulphonated - the insoluble gel which is formed following the sulphonation processing with chlorosulfonic acid and with sulphur dioxide as crosslinking agents which is developed during the reaction in the present of acetic acids as inhibitor regulator, is removed, following processing with ethyl or propyl alcohol extraction of unreacted chlorosulphonic acid , neutralisation with a 30% solution of sodium or potassium hydroxide and is then shaped in a extruder to products of dimensions of 3 to 5 cm - the suphonated products of dimension of 3 to 5 centimetres are strained , fully neutralised and shrunk in a sodium chloride solution or in an electric field and are finally subject to deodorisation under heating and vacuum so that finally products are received of a commercial grade with water absorption of 100-300 times their weight 2. Method according to claim 1 where the insoluble macroplegmatic materials are formed in 10 to 30% solutions of the polymer in chlorinated solvents at normal or slightly raised temperatures up to 50oC with dense 1 to 5% sulphuric acid 0.1 to 0.2 % SbCI5, and 0.05 TiCI4 3. A method according to claims 1 and 2 where the gels of macroplegmatic materials exhibit a high stability for the introduction of ionic groups in a high density , are shaped by passing into a system which contains an array of 2-3 cm one meter long tubes which at their end possess an extruder and a cutting system , for the preparation of materials of dimension between 3 and 5 centimetres 4. A method according to claim 1 , 2 and 3 where dense sulphuric acid, sulphur trioxide, chlorosulphonic acid and oleum with 20, 40 up to 65% of sulphur trioxide content are utilised for the introduction of sulphonic ionic groups at high density. Nitration acid is utilised for the introduction of nitric group., and the copolymer styrene-acrylonitrile where the CN group is hydrolysed to carboxylic group at the reaction conditions , is utilised for the introduction of carboxylic group 5. The chlorosulphonic acid used for the introduction of sulphonic groups also promotes crosslinking with the introduction of sulphon bridges ;acetic acid on a quantity of 10 to 15% in the solution is used as a factor adjusting the degree of crosslinking 6. Method according to claim 5 where the gel which is formed during the sulphonation with chlorosulphonic acid following maturing for 4-5 hours and strained off the solvent which is removed, is then subjected to extraction of the unreacted chlorosulphonic acid with ethyl or propyl alcohol, it is neutralised with sodium or potassium hydroxide and the gel is detached and introduced to the extruded for shaping to products of 3 to 5 cm 7. A method according to claim 3 , 5 and 6 where following sulphonation and shaping according to claim 2 and 6 , the materials are subject to complete neutralisation with which they take a light colour and the ability to absorb water, are then subjected to shrinkage towards with a 10% water content in a 15-25% solution of sodium chloride or in a 20 V electric field and are finally subjected to a deodorization process with heating up at 160 oC and the application of vacuum, following of which commercial products are received to have the ability to retain water intermolecularly up to 100-300 times their weight 8 Method where the crosslinking of the polymers is promoted at conditions of phase separation between the solvent and the addition of an equal volume of dense sulphuric acid. During the process of crosslinking with 2,5 dichlromethyl- 1 ,4-dichlrobenzene with sulphuric acid as the crosslinking catalyst , following the addition of which at 50oC , small spheres are formed which are sulphonated with the addition of sulphuric acid at a temperature of 80oC or with addition of chlorosulphonic acid at normal temperature and these materials are strained shrunk and deodorised The solvent with the dense sulphuric acid are collected and cleaned in a distillation process. 9. Method where inflated polystyrene is immersed,, in oleum sulphuric acid with the promotion of sulphonation large uniform and orderly spheres are formed which have a water adsorptivity 40-70 their weight , depending on the degree of inflation of the polystyrene 10. A method according to claims 1 to 9 where polymers such as polystyrene and its copolymers,. following a crosslinking process for the formation of macroplegmatic products with Mc 30.000 to 50.000 in solutions in chlorinated solvents and using 2,5-dichloromethyl-1 ,4 dichlorobenzene as crosslinking agent and dense sulphuric acid , SbCI5 and TiCI4 on small quantities as catalysts, and following the formation of the insoluble macroplegmatic gel which is extruded forming 3 to 5 cm products prior to the sulphonation process which are sulfonated and treated with neutralisation, shrinkage and deodorisation .With the chlorosulphonic acid where the crosslinking is proceeding with the reaction is formed an insoluble gel which after 4-6 hours ripening is treated with alcohols to remove the unreacted chrolorosulfonic acid and the rest is neutralised, it is shaped in an extruder, then is deodorised to produce a product of brilland colour and of high purity having a capacity to keep water more than 200 times its weight.

Inventors: VALKANAS GEORGE N, VALKANAS, GEORGE, N.
Applicants: VALKANAS GEORGE N, VALKANAS, GEORGE, N.
Application year: 1998
Main classification: C08F8
IPC codes: C08F8