Classifications

• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
  • G05B13/00—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion
  • G05B13/02—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric
  • G05B13/0265—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric the criterion being a learning criterion
  • G05B13/027—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric the criterion being a learning criterion using neural networks only
• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
  • G05B17/00—Systems involving the use of models or simulators of said systems
  • G05B17/02—Systems involving the use of models or simulators of said systems electric

Definitions

• the invention relates generally to a method for producing a hydrophilic polymer, a predictive method, hygiene articles and other chemical products which contain a hydrophilic polymer produced by the method according to the invention, and the use of a polymer according to the invention in hygiene articles and other chemical products and the use of a computer-generated model for the determination of different sizes and a process for the production of further processing products containing hydrophilic polymer. Further details can be found in the following.
• PNC is a linear chain polymer of simple structure, the properties of which are essentially determined by the chain length and the chain length distribution, consequently by the amount of initiator and monomer - as is customary in chain polymers - according to the "Root I Law” and let its further developments be controlled ⁇ Principles of Polymerization, Georg Odian, John Wiley & Sons, second Edition, 1981, pp. 179ff).
• cross-linked polymers are much more complex systems.
• the prediction of the cause-effect relationship between the starting materials, the polymerization and work-up conditions and the physical and chemical properties is much more difficult than with simple chain polymers.
• BEST ⁇ TIGU ⁇ GSKOPIE A further increased degree of complexity compared to only crosslinked polymers is generally found in crosslinked polymers whose repeating units also have additional functionalities, such as charge-bearing functional groups.
• a further increase in the complexity of the polymers can take place in that a material described in the previous section of a further treatment, such as by reaction with additives, is additionally refined in the morphology, for example by forming a core-shell structure.
• hydrophilic polymers also called superabsorbers (SAP)
• SAP superabsorbers
• These are preferably weakly crosslinked, partially neutralized polyacrylates.
• the complexity of the hydrophilic polymers is further increased by the fact that they are not pure polymers, but rather compositions composed of a polymer and other substances, which have a considerable influence on the properties of this composition. For example, a Kem-Sch e structure can be obtained by post-crosslinking. It is often not just a question of the conduct of the polymerization as such; Refurbishment, finishing and packaging steps are also of considerable importance.
• hydrophilic polymers in contrast to the hydrophobic chain polymers, cross-linked with water gels forming hydrophilic polymers are used in many applications for which these polymers have to have a tailored requirement profile. Because of the complexity of the cause-effect relationships in hydrophilic polymers between educts, polymerization, refinement, packaging and processing conditions on the one hand and the property profile of these polymers on the other hand, a transfer of a desired requirement is Development profile on a laboratory scale-compliant formula on a pilot plant or even production scale is not easily possible.
• the degree of complexity of the requirements of these hydrophilic polymers is increased by their further processing.
• the properties of these polymers have a considerable influence on further processing as such and the resulting further processing products. Examples of such further processing are spinning, paper, absorbent sheet and diaper machines which produce absorbent fibers or fiber matrices absorbing water or aqueous liquids, paper, absorbent sheets - also called “cores” - and diapers.
• the degree of complexity will also increased if these hydrophilic polymers are combined with other components.
• other materials such as fibers or adhesives can be used in addition to the hydrophilic polymer.
• the hydrophilic polymer in addition to the hydrophilic polymer further layers such as tissue inlays, acquisition layers and the like may be present which, in cooperation with the hydrophilic polymer, contribute to improved liquid management.
• the properties of the hydrophilic polymer interact with the properties of the w other components and their treatment in the further processing machine.
• the type of further processing machine used and the form of further processing determined thereby also interacts with the hydrophilic polymer and the further components.
• a fiber matrix or a gore can be obtained by a wetlaid, wet wipe or Arilaid system using completely different methods.
• the properties of the hydrophilic polymer with those of fluff such as fluff type (e.g.
• the processing conditions of the fluff preparation in turn have an influence on the fluff properties.
• the properties of the core which are decisively influenced by the hydrophilic polymer, in turn influence the properties of the diaper containing this core and its manufacturing process. Typical properties that are significantly influenced by the hydrophilic polymer with properties are, for example, the rewet and leakage behavior of the further processing products.
• the object of the invention is to make a contribution to overcoming the disadvantages arising from the prior art in connection with the production of hydrophilic polymers.
• Another task is to reduce the effort of laboratory and technical trials in the production of hydrophilic polymers when introducing a new formulation for a certain requirement profile.
• Another task is to shorten the test and running-in phases for setting up further processing machines such as core, diaper, fiber spinning and paper machines.
• Another task is to set a higher degree of requirement profiles for hydrophilic polymers directly in production in order to be able to react more flexibly, cost-effectively and faster to customer requests. In turn, they can produce optimal hygiene articles or other products based on hydrophilic polymers.
• a contribution to the solution of these tasks is made by a method for producing a hydrophilic polymer in a manufacturing device, wherein a computer-generated model, preferably an artificial neural network, controls this manufacturing device.
• the hydrophilic polymer is preferably a water-absorbing polymer, which preferably has
• ( ⁇ 2) 0 to 70% by weight, preferably 1 to 60% by weight and particularly preferably 1 to 40% by weight of polymerized, ethylenically unsaturated monomers copolymerizable with ( ⁇ l),
• the monoethylenically unsaturated, acid group-containing monomers ( ⁇ l) can be partially or completely, preferably partially, neutralized.
• the monoethylenically unsaturated, acid group-containing monomers are preferably neutralized to at least 25 mol%, particularly preferably to at least 50 mol% and moreover preferably to 50-90 mol%.
• the monomers ( ⁇ l) can be neutralized before or after the polymerization.
• Neutralization can also be carried out with alkali metal hydroxides, alkaline earth metal hydroxides, ammonia and carbonates and bicarbonates.
• any other base is conceivable that forms a water-soluble salt with the acid.
• Mixed neutralization with different bases is also conceivable.
• Neutralization with ammonia or with alkali metal hydroxides is preferred, particularly preferably with sodium hydroxide or with ammonia and moreover preferably sodium hydroxide.
• Further water-absorbing polymers produced by the process according to the invention are polymers in which the free acid groups predominate, so that this polymer has a pH in the acidic range.
• This acidic water-absorbing polymer can be at least partially neutralized by a polymer with free basic groups, preferably amine groups, which is basic in comparison to the acidic polymer.
• These polymers are referred to in the literature as “mixed-bed ion exchange absorbent polymers” (MBIEA polymers) and are disclosed, inter alia, in WO 99/34843.
• MBIEA polymers are typically a composition that is, on the one hand, basic polymers that are able to exchange anions and, on the other hand, a polymer that is acidic compared to the basic polymer that is capable of cations exchange, include.
• the basic See polymer has basic groups and is typically obtained by polymerizing monomers that carry basic groups or groups that can be converted to basic groups. These monomers are, above all, those which have primary, secondary or tertiary amines or the corresponding phosphines or at least two of the above functional groups.
• This group of monomers includes, in particular, ethylene amine, allylamine, diallylamine, 4-aminobutene, alkyloxycyclines, vinylformamide, 5-aminopentene, carbodiimide, formaldacine, melamine and the like, and also their secondary or tertiary amine derivatives.
• Preferred monoethylenically unsaturated monomers ( ⁇ l) containing acid groups are those which are mentioned in DE 102 23 060 A1 as preferred monomers ( ⁇ l), acrylic acid being particularly preferred.
• the water-absorbing polymer produced by the process according to the invention consists of at least 50% by weight, preferably at least 70% by weight and moreover preferably at least 90% by weight monomers containing carboxylate groups. It is particularly preferred according to the invention that the water-absorbing polymer produced by the process according to the invention consists of at least 50% by weight, preferably at least 70% by weight, of acrylic acid, preferably at least 20 mol%, particularly preferably at least 50 mol% is neutralized.
• Preferred monoethylenically unsaturated monomers ( ⁇ 2) copolymerizable with ( ⁇ 1) are those monomers which are mentioned as preferred monomers ( ⁇ 2) in DE 102 23 060 A1, acrylamide being particularly preferred.
• the compounds of crosslinker class I achieve a crosslinking of the polymers through the radical polymerization of the ethylenically unsaturated groups of the crosslinker molecule with the monoethylenically unsaturated monomers ( ⁇ l) or ( ⁇ 2), while the compounds of crosslinker class II and the polyvalent metal cations of crosslinker class IV crosslinking of the polymers is achieved by the condensation reaction of the functional groups (crosslinker class II) or by electrostatic interaction of the polyvalent metal cation (crosslinker class IN) with the functional groups of the monomers ( ⁇ l) or ( ⁇ 2).
• the polymer is accordingly crosslinked both by radical polymerization of the ethylenically unsaturated group and by a condensation reaction between the functional group of the crosslinker and the functional groups of the monomers ( ⁇ l) or ( ⁇ 2).
• Preferred crosslinkers ( ⁇ 3) are all those compounds which are mentioned in DE 102 23 060 AI as crosslinkers ( ⁇ 3) of the crosslinking classes I, II, III and IV, where Particularly preferred as compounds of the crosslinking class IN, N'-methylenebisacrylamide, polyethylene glycol di (meth) acrylates, triallylmethylammonium chloride, tetraallylammomum chloride and allylnonaethylene glycol acrylate prepared with 9 moles of ethylene oxide per mole of acrylic acid, and as compounds of the crosslinking class TV Al 2 (SO 4 ) 3 and its hydrates are particularly preferred.
• Preferred water-absorbing polymers produced by the process according to the invention are polymers which are crosslinked by crosslinking agents of the following crosslinking classes or crosslinking agents of the following combinations of crosslinking classes: I, II, III, IV, I II, I III, I IV, I II III, I II IV, I III IV, II III IV, II IV or III TV.
• Further preferred water-absorbing polymers produced by the process according to the invention are polymers which are crosslinked by any of the crosslinkers of crosslinker classes I disclosed in DE 102 23 060 A1, N, N '-methylene bisacrylamide, polyethylene glycol di (meth) acrylates, triallylmethylammonium chloride , Tetraallylammomum chloride and allylnonaethylene glycol acrylate prepared with 9 moles of ethylene oxide per mole of acrylic acid are particularly preferred as crosslinking agents of crosslinking class I.
• the water-absorbing polymer can be prepared from the aforementioned monomers and crosslinkers by various polymerization methods.
• bulk polymerization which is preferably carried out in kneading reactors such as extruders or by ribbon polymerization, solution polymerization, spray polymerization, inverse emulsion polymerization and inverse suspension polymerization.
• the solution polymerization is preferably carried out in water as the solvent.
• the solution polymerization can be carried out continuously or batchwise.
• reaction conditions such as temperatures, type and amount of the initiators as well as the reaction solution can be found.
• initiators which form free radicals under the polymerization conditions and are usually used in the production of superabsorbers can be used as initiators for initiating the polymerization. These include thermal catalysts, redox catalysts and photoinitiators, which are activated by high-energy radiation.
• the polymerization initiators can be dissolved or dispersed in a solution of monomers according to the invention. The use of water-soluble catalysts is preferred.
• thermal initiators All initiators known to the person skilled in the art which decompose into free radicals under the action of temperature are suitable as thermal initiators.
• Thermal polymerization initiators with a half-life of less than 10 seconds are particularly preferred, moreover less than 5 seconds at less than 180 ° C., moreover preferably less than 140 ° C.
• Peroxides, hydroperoxides, hydrogen peroxide, persulfates and azo compounds are particularly preferred thermal polymerization initiators. In some cases it is advantageous to use mixtures of different thermal polymerization initiators. Among these mixtures, those of hydrogen peroxide and sodium or potassium peroxodisulfate are preferred, which can be used in any conceivable quantitative ratio.
• Suitable organic peroxides are preferably acetylacetone peroxide, methyl ethyl ketone peroxide, benzoyl peroxide, lauroyl peroxide, acetyl peroxide, capyrl peroxide, isopropyl peroxydicarbonate, 2-ethylhexyl peroxydicarbonate, t-butyl hydroperoxide, cumene hydroperoxide, t-amyl butyl hexyl perpivalate, t-butyl peryl perpivalate, t-butyl perpylatepivalate , t-butyl per-2-ethylhexenoate, t-butyl perisononanoate, t-butyl permaleate, t-butyl perbenzoate, t-butyl 3,5,5-tri-methylhexanoate and amyl perneodecanoate.
• thermal polymerization initiators are: azo compounds such as azobisisobutyronitrole, azobisdimethylvaleronitrile, 2,2'-azobis- (2-amidino-propane) dihydrochloride, Az; o-bis-amidinopropane dihydrochloride, 2,2 '- azobis- ( N, N-dimethylene) isobutyramidine dihydrochloride, 2- (carbamoylazo) isobutyronitrile and 4,4'-azobis (4-cyanovaleric acid).
• the compounds mentioned are used in customary amounts, preferably in a range from 0.01 to 5, preferably from 0.1 to 2 mol%, in each case based on the amount of the monomers to be polymerized.
• the redox catalysts contain at least one of the above-mentioned per compounds as the oxidic component and preferably ascorbic acid, glucose, sorbose, manose, ammonium or alkali metal hydrogen sulfite, sulfate, thiosulfate, hyposulfite or sulfide, metal salts such as iron-II as the reducing component -ions or silver ions or sodium hydroxymethyl sulfoxylate.
• Ascorbic acid or sodium pyrosulfite is preferably used as the reducing component of the redox catalyst.
• l10 -5 to 1 mol% of the reducing component of the redox catalyst and lxlO "5 to 5 mol% of the oxidizing component of the redox catalyst are used.
• the oxidizing component of the redox catalyst or in addition to this, one or more, preferably water-soluble, azo compounds can be used.
• photoinitiators are usually used as initiators. These can be, for example, so-called ⁇ -splitters, H-abstracting systems or also azides.
• initiators are benzophenone derivatives such as Michler's ketone, phenanthrene derivatives, fluorene derivatives, anthraquinone derivatives, thioxanone derivatives, coumarin derivatives, benzoin ethers and their derivatives, substituted azo compounds such as the radical formers mentioned above Hexaarylbisimidazole or acylphosphine oxides.
• azides examples include: 2- (N, N-dimethylamino) ethyl 4-azidocinnamate, 2- (N, N-dimethylamino) ethyl 4-azidonaphthyl ketone, 2- (K, N-dimemylamino) ethyl 4-azidobenzoate, 5-azido 1- naphthyl-2 '- ( ⁇ , N-dimethylamino) ethyl sulfone, N- (4-sulfonyl azidophenyl) maleic acid, N-acetyl-4-sulfonyl azidoaniline, 4-sulfonyl azido aniline, 4-azido aniline, 4-azidophenacyl bromide, p- Azidobenzoic acid, 2,6-bis (p-azidobenzylidene) cyclohexanone and 2,6-bis (p-azidobenzyliden
• the photoinitiators are usually used in amounts of from 0.01 to 5% by weight, based on the monomers to be polymerized.
• a redox system consisting of hydrogen peroxide, sodium peroxodisulfate and ascorbic acid is preferably used as the “catalyst” or “redox initiator”.
• the polymerization is initiated with the initiators in a temperature range from 30 to 90 ° C.
• the polymerization reaction can be triggered by one initiator or by several cooperating initiators.
• the polymerization can also be carried out by first adding one or more redox initiators. Thermal initiators or photoinitiators are then additionally applied in the further course of the polymerization, the polymerization reaction in the case of photoninitiators then being initiated by the action of high-energy radiation.
• the reverse order that is to say the initial initiation of the reaction by means of high-energy radiation and photoinitiators or thermal initiators and an initiation of the polymerization in the further course of the polymerization by means of one or more redox initiators is also conceivable.
• a hydrophilic polymer preferably the water-absorbing polymer based on the abovementioned monomers
• continuous solution polymerization in which a monomer solution comprising the abovementioned monomers is continuously applied to a polymerization belt. is brought, wherein the monomer solution polymerizes on the polymerization belt to form a polymer gel, the polymer gel is subsequently continuously converted into gel particles in a suitable gel-breaking device and these gel particles are then preferably dried on a drying belt. This is optionally followed by further grinding and sieving of the dried gel particles and, if appropriate, surface treatment, preferably surface postcrosslinking, of the gel particles thus obtained.
• the dried gel particle is in each case treated with a postcrosslinker which can be reacted with the carboxyl groups of the polymer, preferably as an aqueous solution with a concentration in the range from 0.001 to 50, preferably in the range from 0.01 to 20% by weight based on the postcrosslinker solution, with an amount in the range from 0.0001 to 20, preferably in the range from 0.001 to 10% by weight, in each case based on the dried gel particle.
• Compounds of crosslinking classes III and IV or mixtures thereof are suitable as postcrosslinkers, ethylene carbonate or aluminum sulfate being particularly preferred.
• DE 40 20 780 Cl the disclosure of which forms part of this text. These include Al compounds and polyols, preferably diols, or Al compounds and ethylene carbonate.
• DE 199 09 653 AI and DE 199 09 838 AI as part of this disclosure.
• the manufacturing device is controlled by determining at least one process parameter and at least one process variable based on this at least one process parameter.
• state variables that are related to the manufacturing process can be considered as process parameters.
• state variables those which are preferred during the Procedural variations are subject.
• State variables that form such process parameters are, for example, temperatures, pressures, flow velocities, concentrations, moisture content, electrical currents, electrical resistances, rotational and conveying speeds or mechanical forces and densities, with temperatures, concentrations, moisture content, throughput quantities and mechanical forces being preferred, and temperatures and mechanical forces Forces are also preferred.
• the process variables are variables that are actively set and / or adjustable as part of the control of the manufacturing device.
• This setting can be made indirectly or directly.
• An indirect process variable can be, for example, a control signal, which takes place in particular electronically.
• This control signal can, for example, cause a valve opening and thus a stronger addition of a certain substance.
• This increased substance addition in turn has an effect on a process parameter, in this case a certain concentration of a certain substance.
• Another example of a process size is the increase or decrease in the performance of a heat generator. The change in performance has an effect on the temperature as a process parameter.
• process variables are, for example, heating or cooling output, addition quantities, transport speeds such as are set in particular on conveyor belts or in transport screws or extruders, rotational speeds of comminution tools, in particular of mills.
• Process parameters thus represent quantities that can be measured or can be measured. Process parameters result from the settings according to the process variables.
• the device that can be used for the method according to the invention includes an educt area, an adjoining polymerization area and also a first assembly area that follows the same. This can be followed by a post-networking area, which may include a further has rich. In the manufacturing device designed in this way, at least the following steps can be carried out successively in the corresponding areas:
• acrylic acid-based, partially neutralized polyacrylate as the hydrophilic polymer
• acrylic acid be partially neutralized by bringing the acrylic acid into contact with sodium hydroxide solution.
• a degree of neutralization of the acrylic acid in the range from 30 to 80, preferably 50 to 75 and particularly preferably 60 to 73 mol% is established.
• a further sub-step of the educt preparation step sets the temperature which is most suitable for the polymerization in a cooling step.
• the temperature of the monomer, comonomer and crosslinker mixture is a process parameter.
• the cooling or heating power that acts on this mixture in turn represents one Process size represents.
• the starting material mixture has a temperature of 1 to 20, preferably 2 to 15 and particularly preferably 3 to 7 ° C. before it is fed to the polymerization.
• a further sub-step of the educt preparation step which can either be upstream or downstream, preferably downstream, is a step in which the oxygen content of the educt mixture is reduced.
• This step can also serve the task of foaming the educt mixture, preferably immediately before the polymerization, so that the hydrophilic polymer formed during the polymerization has a porosity or even a foam-like structure, as described, for example, in EP 0 827 753 AI and a volume ratio of 1.01 to 5, based on the educt volume prior to gassing, is preferred, in which case it may be advantageous to add a surface-active substance to the educt mixture Stripping the content of oxygen or displacing protective gas, preferably nitrogen, the density of the educt mixture and the concentration of a surface-active agent can be determined as process parameters, with the measurement of the oxygen or protective gas concentration being particularly important the amount added or Flow of shielding gas and - in the case of the formation of a foam - the amount of surfactant - important process variables.
• the polymerization step can also be subdivided into different sub-steps, which may depend on the polymerization device used. Both stationary and continuously working polymerization devices are possible here, with the continuously working being preferred.
• An important group of process parameters in a continuously operating polymerization device are the flow of the product mixture and, in the event that a catalyst is used in addition to the initiator, as is the case in particular in redox-initiated polymerizations, the flow of the catalysts.
• the associated process parameter is the residence time of the starting material mixture which gradually polymerizes in the polymerization device.
• conveyor speeds of the means of transport come into consideration as the process variable. These means of transport are usually either polymerisation belts or screws or conveyor stirrers.
• the belt speed represents a process variable.
• the rotation speed of these screws or conveyor stirrers and if the screw or conveyor stirrer paddles can be varied in their angle of attack this also represents a process variable Entry of a polymerization aid may be advantageous.
• the addition of other blowing agents such as carbonates, preferably sodium carbonate, is to be mentioned, this preferably as an aqueous solution with preferably in the range from 0.5 to 50, preferably in the range from 1 to 25,% by weight blowing agent based on the blowing agent solution.
• the quantity of blowing agent solution to be determined via valve positions represents a process variable which is influenced by various process parameters, such as density of the polymerization solution, density or porosity of the hydrophilic polymer and others.
• the first assembly step provided in the first assembly area can likewise be broken down into various sub-steps, which is preferably a comminution, drying and grinding step.
• the process parameters in the comminution step are in particular the discharge length per time of polymer from the direction of polymerization and the consistency of the polymers.
• the consistency of the polymer can be determined on the one hand by means of suitable mechanical tests, for example by pressure loading or tensile elongation tests, directly or indirectly via the current consumption of the corresponding comminution tools.
• Another process parameter of the size reduction step can be the compressibility of the polymer leaving the size reduction step.
• the hydrophilic polymer is obtained after the polymerization step as a hydrogel containing water.
• the water content, the degree of comminution and also the temperature of the polymer present as a hydrogel can have an influence on the compressibility.
• Process variables set in the comminution step are preferably the speeds of the comminution devices such as kneaders and a subsequent wolf and, if homogenization of the comminuted hydrogel is provided, the speed of the homogenization drum.
• the temperature of the hydrogel at the end of the comminution step can also be important. This applies in particular if post-initiation is provided, which can be advantageous for reducing the residual monomer content of the hydrogel.
• the shredding is followed by drying. This can be divided into different drying cells. On the one hand, the drying process parameters are:
• Hydrogel preferred. These can be determined on the one hand for the drying as a whole and also for the individual cells in the drying. Another process parameter is the temperature in the drying process and, if there are several cells, in at least some, preferably each of the cells
• a preferred process parameter in the case of grinding is the consistency of the now essentially water-free hydrophilic polymer. This can be done directly via mechanical load search how shear tests or penetration tests are determined. However, the consistency can also be determined indirectly by the current consumption of the grinding tool or tools. In addition to the temperature of the hydrophilic polymers which pass from the drying into the grinding, their residual water content can also be determined as process parameters for the grinding. In addition to the speed of the grinding tools used in the grinding process, the process variables which can be used are also their setting, in particular the grinding gap set between two grinding tools.
• the movement frequency (usually vibration) of a carrier responsible for ensuring that the mills are acted on as evenly as possible - also called "hopper" - can be advantageous for a good grinding result.
• the frequency of this hopper which represents a process variable, is in the range from 1 to 100 Hz.
• the hydrophilic polymer powder obtained in the first finishing step can optionally be subjected to a post-crosslinking step, which in turn is subdivided into a series of successive sub-steps.
• the hydrophilic polymer powder is first stored temporarily in a pre-product silo.
• the temperature and humidity of the hydrophilic polymer powder are determined in these as process parameters.
• Further process parameters of the postcrosslinking step are the throughput of hydrophilic polymer powder and of postcrosslinkers used for the postcrosslinking reaction.
• the preferred process variables in connection with the postcrosslinking step relate to the control of the metering devices for hydrophilic polymer powder, one or more postcrosslinkers and the speed of the mixer.
• Another important process parameter of the post-crosslinking step is the temperature of the mixer.
• the mixer has different mixing sections with different temperatures, at least two, preferably all, temperatures of these mixing sections are Sections preferred as process parameters.
• the process variable associated with the temperature is the heating power of the mixer or the individual sections of the mixer. This heating power can be provided, for example, by more or less strong steam input into the mixer tempered by steam or in the mixing sections tempered by steam.
• Another process parameter is the temperature of the hydrophilic polymer after passing through the mixer.
• Another process parameter after passing through the mixer can be the moisture of the hydrophilic polymer.
• the hydrophilic polymer obtained above can be mixed with further substances. These can counteract the formation of dust, as is the case with polyethylene glycol as a dust reducer.
• Other typical auxiliaries or confectioning agents are water for adjusting the absorption properties, activated carbon for coloring or binding odors, carbohydrates such as starch, ligriin, Si compounds, in particular Si oxides and green tea extract.
• the at least one process variable preferably the artificial neural network
• this calculation is based on at least 2, preferably at least 5, particularly preferably at least 8 and moreover preferably at least 10 process parameters. It is further preferred that not only one process variable, but at least 2, preferably at least 4 and particularly preferably at least 10 process variables are calculated in this way.
• fuzzy logic In addition to the artificial neural network or in connection with it, a model described in the literature as "fuzzy logic” can also be invented. be used properly.
• fuzzy logic there is a publication published under http://privat.sefarth.de/oiav/neuro-fuzzy-syteme.html for a seminar lecture by Babara and Olav Seyfarth on cooperative and hybrid neuro-fuzzy systems at the chair in front of Prof. Dr , Karl Heinz Meisel from June 19, 2000 and the article Successful Application of Fuzzy Logic and Fuzzy Controle (Part 2), Automation Technology 50, 511ff (2002) by Bern- Markus Pfeiffer et al. and 9.
• this method in particular the polymerization step and, moreover, preferably the polymerization step and the first finishing step run continuously.
• continuous is understood to mean that the production process is not carried out in portions or batches, but rather continuously. It is therefore preferred that the method according to the invention is divided into at least two method steps. In each of these at least 2 process steps, at least one step parameter is preferably determined as the process parameter.
• the at least one step parameter influences at least one process variable. It is preferred that this process variable lies in a different process step than the one in which the step parameter was determined. It is particularly preferred that the at least one step parameter influences at least two process variables, wherein at least one of these two process variables lies in a method step that lies outside the method step in which the step parameter was determined.
• control is carried out by an experience estimate assigned to at least one experience parameter.
• the experience parameter is at least one, preferably at least two and moreover preferably at least three physical or chemical properties of a hydrophilic polymer.
• the experience parameters in the method according to the invention are preferably characterized by at least one, preferably each, of the following properties:
• P 1 the retention of an aqueous liquid (CRC)
• P2 the absorption of an aqueous liquid
• P3 the absorption of an aqueous liquid against pressure
• P4 the absorption rate of an aqueous liquid
• P5 the absorption rate of an aqueous liquid against pressure
• P6 the particle size distribution
• P7 the residual monomer content .
• the experience parameters in particular the above, can be determined by methods which are generally familiar to the person skilled in the art. In particular, determinations by so-called ERT methods (EDANA Recommended Tests - EDANA: European Diaper And Nonwoven Association) are preferred.
• each of the abovementioned properties represents an embodiment of a possible experience parameter.
• Particularly preferred embodiments of property combinations as experience parameters are the combinations shown below as letter combinations: Pl P2 P3 P4 P5 P6 P7, Pl P2, Pl P3, preferably P1P3 P4P5P6P7P8P9 and particularly preferably P1P3P4P5.
• the wealth of experience is formed by a learning process in which process parameters, process variables and the experience parameters of the hydrophilic polymer obtained in each case when using these process parameters and process variables are determined. A series of such determinations creates a data set on the basis of which the computer-generated model or the neural network is trained.
• target experience parameters are specified as target experience parameters.
• the associated target process parameters and target process variables are initially determined via the artificial neural network. These begin to manufacture this particular hydrophilic polymer.
• the initially specified target process variables can be modified, if necessary, and the actual actual process variables can be brought up to these target process variables.
• Another possibility for correcting the desired process parameters is to determine the actual process parameters on the hydrophilic polymer obtained at the beginning of the manufacturing process and to compare them with the desired process parameters by means of the artificial neural network. This comparison also has an impact on the process variables in general and the target process variables in particular.
• the wealth of experience is manifested by the computer-generated model, preferably the artificial neural network.
• This manifestation can take place, for example, in that a suitable computer is suitable for neural networks Form typical interconnections. It is therefore further preferred that in the method according to the invention the wealth of experience can be obtained through a learning process.
• process parameters and process variables particularly preferably process variables for operating, preferably for starting, of a manufacturing device for hydrophilic polymers can be predicted on the basis of at least one, preferably at least two and particularly preferably at least seven, experience parameters. Furthermore, starting from at least one, preferably at least two and particularly preferably at least 10 process parameters or from at least one, preferably at least two and particularly preferably at least ten process variables or both, empirical parameters and thus physical or chemical properties of a hydrophilic polymer for a specific device for producing hydrophilic polymers can be predicted.
• the method according to the invention includes an artificial neural network with at least one first artificial neuron and at least one, preferably at least two and particularly preferably at least four further artificial neurons following the first artificial neuron.
• Input signals XJ can get into the neuron via these connections or also from the environment.
• a neuron in particular comprises weights Wj for each connection between this neuron and other neurons and at least one activation function which determines the output signal of the neuron depending on, for example, an input signal weighted by the weights of the input signals.
• a neural network which comprises at least two neurons, each neuron being connected to at least one other neuron, can learn from experience, for example a wealth of experience, and thus can be “trained” for example The learning process can be reflected, for example, in a change in at least one of the weights WJ of at least one neuron. Further details can be found in 8. Neural Networks at http://www.iicm.edu/ grab7nodel0.html.
• inputs are made in the first artificial neuron by an input signal.
• This input signal is preferably directly or indirectly a process parameter.
• the further artificial neuron is output by an output signal.
• This is preferably an electrical signal that acts directly or indirectly as a process variable or on a process variable. It is therefore preferred that the at least one process parameter correlates with at least one input signal of the first artificial neuron. Furthermore, it is preferred according to the invention that the at least one process variable correlates with at least one output signal of the at least one further artificial neuron.
• the empirical parameters often correlate with the weights or weighted sums of the activation functions that are formed in the model generated in the computer.
• a prediction method for predetermining at least one, preferably each, of the following variables makes a further contribution to solving the tasks according to the invention:
• G3 of a G-experience parenter in connection with a hydrophilic polymer or its production or both, comprising the following steps:
• V2 Operating a production of a hydrophilic polymer, V2 determining at least one of the V variables i) a V process parameter, ii) a V process variable, iii) a V experience parameter, V3 processing the at least one V variable in a data processing unit Development of a wealth of experience in the form of a computer-generated model, preferably an artificial neural network, V4 Providing at least one G variable based on this wealth of experience.
• the production of a hydrophilic polymer is preferably carried out in the production device for which a G size is to be predetermined.
• This serves, in particular, the purpose that with as few or no preliminary tests as possible in an existing manufacturing device, preferably a production plant, the most reliable prediction can be obtained.
• the production takes place in the production device under different conditions. In this way, a quantity of data can be obtained which allows the generation of an artificial neural network, which leads to reliable predictions even with larger deviations.
• step V2 it is preferred to determine the different sizes in so-called data records. It is preferred here that the sizes of a certain hydrophilic polymer are recorded in a temporally resolved manner during the production process.
• the data set for a certain hydrophilic polymer shows the sizes from the educt preparation step and the if, for this hydrophilic polymer, sizes from the polymerization step and the sizes corresponding to this hydrophilic polymer and the subsequent steps a little later when passing through the first finishing step are determined. This allows a data set to be defined as the sum of all sizes of a specific product along the manufacturing process.
• the quality of the computer-generated model generally improving with the amount of data records.
• the computer-generated model can be improved by means of a weighted selection of data records - generally referred to in the literature as “typicals”.
• a computer-generated model preferably a neural network
• a suitable computer by forming suitable links. This process can also be repeated again and again during the production of the hydrophilic polymer, which leads to constant further development of the computer-generated model or of the artificial neural network.
• the predictability of the computer-generated model or of the artificial neural network increases with the duration or repetition of the learning steps VI to V3, the increase from repetition to repetition decreasing.
• the provision of the G variables based on the experience thus obtained preferably takes place in that one of the G variables is specified and the other G variables are determined on the basis of the artificial neural network.
• a certain requirement profile of a hydrophilic polymer is predetermined by certain G experience parameters and that G process variables and G process parameters are now determined.
• a prediction is sought for the case in which a G method variable is varied.
• the artificial neural network then provides a prediction of the effects of the changes. change in the G process size to the G process parameters and in particular to the G experience parameters and thus the property profile of the hydrophilic polymer.
• This contribution can in particular lie in the fact that for the start-up phase at the start of the production of a hydrophilic polymer, process variables are preset accordingly in the different areas of the production device, and the start-up phase can thus be significantly shortened until a stable state is reached.
• the invention further relates to composites, hygiene articles, fibers, foils, foams, moldings, floor improvers, flocculants, paper, textiles, water treatment or leather gums, preferably hygiene articles, in particular baby diapers, sanitary napkins, tampons and incontinence articles, particularly preferably baby diapers, comprising a hydrophilic polymer which can be obtained by the production process according to the invention.
• the invention relates to the use of a hydrophilic polymer, which is obtainable by a production process according to the invention, in composites, hygiene articles, fibers, foils, foams, moldings, floor improvers, flocculation, paper, textile, water purification or leather auxiliaries, preferably wise in hygiene articles, especially in baby diapers, women's bandages, tampons and incontinence articles, particularly preferably in baby diapers.
• a method for producing a further processing product containing a hydrophilic polymer is proposed in a further processing machine, including as process steps: providing of the hydrophilic polymer and at least one further processing component bring the hydrophilic polymer and the at least one further processing component into contact to obtain the further processing product, wherein a computer-generated model, preferably an artificial neural network, controls the further processing machine.
• the polymer is obtained by the process according to the invention.
• the further processing product can in particular be absorbent composites, diapers, paper, hygiene articles, female bandages, incontinence articles and the like.
• papers water or aqueous liquids-absorbent papers such as wiping, kitchen or toilet papers are particularly preferred.
• a further processing component is understood to mean, for example, fibers such as, in particular, cellulose fibers, polymers, adhesives, water, solvents and others, which are different from the hydrophilic polymer.
• a configuration is particularly advantageous here in which the hydrophilic polymer is produced in a controlled manner by a first neural network and the further processing machine is controlled by a second neural network, a first and a second neural network being networked with one another at one or more points in a particularly advantageous manner can be.
• a first and a second neural network can also be connected to form a common neural network.
• the further processing of polymers, in particular of hydrophilic polymers, with further processing components to form a further processing product containing a hydrophilic polymer in a further processing machine represents a complex task for a control process, since there are a large number of process parameters and a large number of process variables.
• W process parameters are referred to here as W process variables in order to be able to distinguish them from the process variables and process parameters introduced above.
• the W process parameters and / or the W process variables are coupled to one another, in particular there is a complex and / or non-linear coupling of a large number of variables which lead to an almost chaotic behavior.
• the same can also apply to a change in a process variable and / or a process parameter in the production of the hydrophilic polymer.
• the controller or the neural network can react appropriately for future changes of at least one process variable, W process variable, a process parameter and / or W process parameter in order to nevertheless obtain the desired properties of the polymer and / or the further processing product.
• Neurons that can not only process discrete values as input signals can be designed particularly advantageously.
• the computer-generated model is based alternatively or cumulatively on the principle of "fuzzy logic".
• the computer-generated model of the manufacturing device and the computer-generated model of the further processing machine interact with one another.
• the influences of at least one process parameter and / or at least one process variable on the properties of the further processing product can advantageously be taken into account in the control or regulation of the further processing machine.
• the two computer-generated models can communicate with one another via defined interfaces, via which in particular at least one process parameter, at least one process variable, at least one W process parameter and / or at least one W process variable can be exchanged and / or compared.
• the two computer-generated models can also be networked with one another. If the computer-generated models are designed as neural networks, it is in particular possible for both computer-generated models to have one or more common neurons.
• control takes place by determining at least one W process parameter and via at least one W process variable based on this at least one W process parameter. This applies in particular to a corresponding regulatory process.
• the control or regulation can alternatively or additionally also take place by determining at least one process parameter and via at least one process variable based on this at least one process parameter.
• the determination of the at least one W process parameter and / or the process parameter can be carried out directly via a corresponding measuring sensor, for example a temperature, pressure, humidity, density, concentration and / or pH value sensor, or indirectly by determining another Measured variable and subsequent conclusion or conclusion on the desired process parameters and / or W process parameters.
• the computer-generated model preferably the artificial neural network, calculates the at least one W method variable.
• the computer-generated model calculates the W process variable based on at least one process parameter and / or at least one W process parameter.
• more than one W process variable can be calculated from at least one process parameter and / or at least one W process parameter.
• a process parameter and / or a W process parameter can thus flow into one or more process variables and / or W process variables.
• this method takes place continuously.
• the continuous calculation of process variables and / or chemical process variables, as well as the continuous monitoring of at least one physical and / or chemical property of the further processing product advantageously allow control and / or regulation, for example, the larger - in particular sudden - changes in the properties of the further processing product effectively prevented and which, for example, allows a very precise setting and monitoring of properties of the further processing product and thus enables production with only a small tolerance range of this property.
• a continuous process is also understood to mean a process in which the further processing product is not produced in batches and / or in which the output of further processing product per unit of time is essentially constant.
• a W step parameter is determined as a W process parameter.
• W process parameter represent, for example, this type of fluff, moisture and / or type of mill (for fluff defibrillation).
• the at least one W step parameter influences at least one W process variable. It is preferred here that this W-process variable lies in a different process step than the one in which the W-step parameter was determined. It is particularly preferred that the at least one W step parameter influences at least two W process variables, at least one of these two W process variables being in a method step that lies outside the method step in which the W step parameter was determined.
• W process variables are, for example, fluff or fiber feed, variable defibrillation gaps, conveying speed, sieve size (the sieves in a hammer mill), hammer type (material, hardness or design), air speed or volume flow and / or air flow.
• control takes place by means of a wealth of W experience assigned to at least one W experience parameter.
• a corresponding regulation can also take place analogously.
• the W experience parameter is at least one, preferably at least two and moreover preferably at least three physical and / or chemical properties of a further processing product, preferably a diaper.
• the W experience parameter in the method according to the invention is preferably characterized by at least one, preferably each, of the following properties: Wl Rewet, W2 leakage, W3 wicking, W4 absorption speed, W5 spreading of the liquid (“spreading” in the direction and area of spreading), W6 Integrity when dry or wet.
• W1 to W6 each represent a W experience parameter individually or in any conceivable combination.
• the following combinations each represent a configuration of a W experience parameter: W1W2W3W4W5; W2W3W4W5W6; W1W3W4W5W6; W1W2W4W5W6; W1W2W3W5W6; W1W2W3W4W6; w1w2; W1W3; W1W4; W1W5; W2W3; W1W4; W1W5; W1W6; W3W4; W3W5; W3W6; W3W4W5; W4W5W6; W1W5W6 or W1W3W5.
• the wealth of W experience is manifested by the computer-generated model, preferably by the artificial neural network.
• the W experience and / or the experience manifests itself in the connection weights of the individual connection of the neural network.
• the W experience pool is adjusted by changing the corresponding connection weights.
• the wealth of W experience can be obtained through a learning process. This can be created with the learning process for the wealth of experience in connection with the hydrophilic polymer.
• the artificial neural network comprises at least one first artificial ches neuron and at least one further artificial neuron following the first artificial neuron. Further details can be found in 8. Neural Networks at http://www.iicm.edu/riff/nodelO.htrnl. It is further preferred in the method according to the invention that an input is made into the first artificial neuron by an input signal. This input signal is preferably directly or indirectly a process parameter.
• the further artificial neuron is output by an output signal.
• This is preferably an electrical signal that acts directly or indirectly as a process variable or on a process variable. It is therefore preferred that the at least one process parameter correlates with at least one input signal of the first artificial neuron. Furthermore, it is preferred according to the invention that the at least one process variable correlates with at least one output signal of the at least one further artificial neuron.
• the experience parameters often correlate with the weights or weighted sums of the activation functions that are formed in the computer-generated model.
• the further processing machine is a fiber spinning, fiber matrix, paper, core, wound dressing or diaper machine.
• further processing products are produced from a hydrophilic polymer and at least one further processing component, preferably from two or more further processing components.
• the properties of these further processing products depend in particular on the physical and / or chemical properties of the polymer, wherein in particular only a small change in the properties of the polymer can bring about a comparatively large change in the properties of the further processing product.
• the control or regulation is advantageous, in particular via at least one neural network.
• the further processing product is fibers, fiber matrices, paper, cores, wound dressings or diapers.
• WG1 of a W process parameter or process parameter WG2 of a W process variable or process variable
• the method has the following steps: VI operating a production of a further processing product, V2 determining at least one of the WV variables i. a WV process parameter, ii. a WV process size, iii. a WV experience parameter, V3 processing the at least one WN variable in a data processing unit to form a wealth of experience in the form of a computer-generated model, preferably an artificial neural network, V4 providing at least one WG variable based on this wealth of experience.
• W process parameters, process parameters, W process variables, process variables and W experience values and experience values can be predicted by the prediction method according to the invention.
• the W experience values include in particular physical and / or chemical properties of the further processing product. These include in particular the parameters W experience parameters referred to above. In this way, W process parameters, process parameters, W process variables and / or process variables can be predicted in particular on the basis of predetermined properties of the further processing product. This leads to less experimentation and allows a much faster implementation of a generation of processing products.
• a prediction method for predetermining at least one of the following WG variables WG1 of a W process parameter or process parameter, WG2 of a W method variable or process variable, WG3 of a W experience parameter or experience parameter, in connection with a hydrophilic polymer and / or a further processing product or its production or both are proposed, at least one WG size being provided based on an existing wealth of experience.
• the existing wealth of experience is based in particular on the experience of the computer generated model, in particular the neural network, that was gained before the size of the shared flat was made available. This existing experience can be gained by the prediction method described above or by one of the production methods described here.
• 1 is a schematic representation of a manufacturing device according to the invention
• FIG. 5 shows a schematic illustration of a post-crosslinking area and a further confectioning area
• FIG. 7 schematically shows a detail of the further processing machine according to FIG. 6;
• a manufacturing device 1 has a computer 2, which is preferably located in a process control center of the manufacturing device.
• This computer 2 is connected to the different areas of the manufacturing device 1, such as a starting area 3, a polymerization area 4, a first assembly area 5, a post-crosslinking area 6 and a further assembly area 7 via at least one process parameter line 8 and at least one process size line 9. It is preferred here that the individual areas and - if available - their subdivisions are each connected to the computer 2 via a process parameter line 8 and a process variable line 9.
• a water supply regulated via a water supply regulator 10 a sodium hydroxide supply regulated via a sodium hydroxide supply exciter 11, an acrylic acid supply regulated via an acrylic acid supply regulator 12, a crosslinking supply via a crosslinking supply regulator 13 and a cross connection supply lead out a comonomer feed regulator 14 controlled comonomer feed into an eductor 15.
• the respective quantities of water, sodium hydroxide solution, acrylic acid, crosslinking agent and possibly supplied comonomer can be set as process variables via the regulators 10, 11, 12, 13 and 14.
• One or more probes 16 can be arranged in the controllers 10, 11, 12, 13 and 14 or in the educt mixer 15 or in both, with which the states, in particular the temperature, are determined as process parameters of the individual educt parts fed to the educt mixer 15.
• the educt parts flow meter 17 provided in the educt mixer 15 or in several educt section flow meters 17 provided in the respective controllers 10, 11, 12, 13 and 14 can also determine the educt parts supplied to the educt mixer 15 per unit of time and in this way and In this way, the concentration ratios present in the educt mixer 15 and thus in the educt mixture can be concluded.
• An educt cooling 18 connects to the educt mixer 15.
• the educt cooling 18 has a coolant inlet 19 and a coolant outlet 20, the amount of coolant per time and the temperature of the coolant regulating the cooling capacity of the educt cooling 18 as process variables.
• the educt cooling 18 is followed by a gas exchanger 21, which has a further educt probe 16 with which, on the one hand, the temperature of the educt mixture located in the gas exchanger 21 can be determined as a process parameter.
• the gas content in particular the oxygen content in the educt mixture, can be determined as a further process parameter via the educt sensor 16.
• the determination of the proportion of gas bubbles via the density of the gassed educt mixture can likewise be carried out as a further process parameter via the educt sensor 16.
• the quantity of protective gas introduced into the gas exchanger 21 can be regulated as a process variable via a protective gas controller 22.
• the foam formation required in the educt mixture can be set via the protective gas regulator 22, in particular via the regulation of the gas outlet.
• FIG. 3 a shows a polymerization area 4 in the form of a trough belt polymerization device which follows the educt area 3.
• the starting material mixture originating from the gas exchanger 21 is fed into a polymerization chamber 24 via a starting material flow meter 26 via the starting material entry 23.
• This polymerization space 24, which is shaped like a trough by a belt, continues to trim via a catalyst or auxiliary entry 25, tracked by a catalyst flow meter 27, polymerization initiating and accompanying catalysts and auxiliary agents into the starting material mixture.
• the polymerization reaction takes place with the formation of a polymer 28 which is discharged from the polymerization space 24 on the one hand by the movement of the polymerization belt 31 forming the polymerization space 24 and on the other hand by a polymer conveyor 29 which conveys the polymer 28 formed.
• the process parameters of the polymerizations are determined via one or more polymerization sensors 30 arranged above the polymerization space 24. on, in particular temperature and throughput.
• the speed of the polymerization belt 31 in the direction of movement 35 represents important process variables of the polymerization step.
• the speed of the polymerization belt 31 is controlled by a drive 32 and thereby by a gear 33 driven belt roll 34, on which the polymerization belt 31 rests, regulated.
• Polymerization conveyor 29, polymerization belt 31, drive 32, gear 33 and belt roll 34 are received by a holder 36. Further details on the design and implementation of the polymerization region 4 by means of belt polymerization can be found, inter alia, in DE 35 44770 A1, to which reference is hereby made as part of the present disclosure.
• 3b and 3c show a further embodiment of a polymerization region 4 in the form of a kneading reactor.
• the educt mixture is introduced into a reactant inlet 23 formed on a housing 39, followed by an educt flow meter 26, into a polymerization space 24 delimited by the housing 39.
• catalysts or auxiliaries are introduced into the polymerization space 24 via a catalyst entry 25 followed by a catalyst flow meter 27.
• the housing 39 receives a stirrer 37 in the reaction chamber 24.
• the lower housing area delimiting the reaction space 24 has a cooling 38.
• a screw-shaped polymer conveyor 29 for discharging the polymer 28 is arranged under the stirrer 37.
• the states of the polymerization device designed as a kneading reactor which are relevant as process parameters are determined by one or more polymerization sensors arranged or arranged above or in the polymerization space 24. Further details on the polymerization region 4 designed as a kneading reactor can be found, inter alia, in US Pat. No. 4,625,001 and EP 0 508 810 A1, the contents of which each form part of this disclosure.
• FIG. 3d shows a polymerization region 4 designed as a multi-screw extruder. In such a reactor, the starting material mixture and catalyst or auxiliary agents are introduced, comparable to FIGS. 3a, 3b and 3c, so that reference is made here to the explanations regarding these figures.
• Two or more screws 40 are accommodated in a housing 39, which extend along a longitudinal axis of the housing and are moved by a drive 42.
• the housing 39 encloses the screws 40 in a form-fitting manner.
• the screws 40 have screw paddles 41 which engage in one another and have both a kneading and a conveying action away from the educt entry 23.
• a polymer conveyor 29 designed as a screw for discharging the polymer 28 is provided on the educt entry opposite the end of the housing.
• This multi-screw reactor can be used to carry out a process for the continuous production of hydrophilic polymers, where ⁇ ) water-soluble, monoethylenically unsaturated monomers, ⁇ ) 0.001 to 5 mol%, based on the monomers ( ⁇ ), of monomers containing at least two ethylenically unsaturated double bonds as crosslinkers and ⁇ ) 0 to 20 mol%, based on the monomers ( ⁇ ), water-insoluble monoethylenically unsaturated monomers in a preferably 20 to 80% by weight aqueous solution in the presence of initiators at temperatures in the range from 0 to 140 ° C.
• the aqueous solution of the monomers together with the initiator and optionally an inert gas is continuously fed to a mixing kneader with at least two axially parallel rotating shafts, with several kneading and transport elements on the shafts that promote the mixing kneader at the beginning giving substances in the axial direction to the end of the misc cause the heat dissipation by evaporation of water from the reaction mixture at least 5% of the heat of reaction and the proportion of heat dissipation by product discharge is at least 25% of the heat of reaction and the remaining heat is removed by cooling the reactor walls.
• the heat dissipation can be determined via one or more polymerization sensors 30, which are arranged either in or at the end of the polymerization space 24. Suitable process parameters can be determined via these polymerization sensors 30. For example, the heat dissipation can be determined via temperature measurements. In addition to the screw speed, which can be adjusted via the drive 42, the process variables also include the position of the screw paddles 41, on which their kneading and transport capacity depends. Further details on this form of the multi-screw reactor can be found in. a. from DE 199 55 861 AI, the content of which is hereby considered part of the present disclosure. Suitable multi-screw extruders can also be obtained commercially from List AG, Switzerland.
• the fourth confectioning area 4 shows a first assembly area 5, which adjoins the polymerization area 4 via a polymer entry 43.
• the first confectioning area has different sub-areas, with this being at least one comminution area 44, a subsequent drying area 45 and a grinding area 46 following the drying area.
• the comminution area 44 in turn has at least one cutter 47 for dividing the polymer 28, a subsequent wolf 48 for tearing the comminuted polymer and possibly a homogenizer 49, which is preferably designed as a drum and for the uniform distribution of the various hydrogel pieces emerging from the wolf leads.
• the shredding area 44 has at least one shredding sensor, via which the process parameters of the shredding area, in particular the temperature, the water content and possibly the compressibility of the hydrogel of the hydrophilic polymer located in the shredding area, or these parameters are determined in the hydrogel leaving the shredding area.
• Process variables of the comminution area 44 can be seen in particular the energy introduced into the hydrogel via the cutter 47 and the wolf 48. Consequently, the cutting performance and the wiping performance as well as the rotational speed of the drum are preferred process variables of the comminution step. Further details of the comminution device result, for example, from EP 0 827443 AI, the content of which forms part of the present disclosure.
• the drying area 45 following the comminution area 44 is preferably designed as a zone air dryer with different cells 52.
• the hydrogel of the hydrophilic polymer emerging from the shredding area is guided through the individual cells of the dryer via a conveyor belt 51, the belt of which moves in the direction of movement 35, and essentially freed of water by drying.
• a dry sensor 76 can be provided in the dryer, preferably in at least two, preferably in at least each of the cells 52.
• Process variables of the drying step include, in particular, the heat output of the dryer and the belt speed of the conveyor belt 5l. Particularly suitable dryers are described in Modern Superabsorbent Polymer Technology FL Buchholz, AT Graham, Wiley-VCH, 1998, pages 87 ff.
• the drying area 45 is followed by the milling area 46, which has at least one, preferably at least two mills, preferably a coarse mill 53 and a fine mill 54, each of which has milling tools 55, two milling tools 55 always forming a milling gap 56.
• the grinding gap 56 is larger in the coarse mill 53 than in the fine mill 54.
• the grinding area 46 has at least one grinding sensor 57 for determining process parameters.
• the process parameters of the grinding step include, in particular, the moisture content, the temperature and the particle size or chunk size of the grinding stock entering the grinding area as the dried hydrophilic polymer. Another group of process parameters are the properties of the millbase leaving the grinding area.
• the preferred process variables of the grinding area 46 include, in particular, the speeds of the grinding tools 55 and the grinding gap 56 of the individual mills. Further details on the grinding step can be found in Modern Super sorbent Polymer Technology FL Buchholz, AT Graham, Wiley-VCH, 1998, pages 93 ff.
• the regrind leaving the grinding area 46 via a grinding outlet 58 enters the post-crosslinking area 6 via a grinding inlet 59.
• the particulate hydrophilic polymer which is now in powder form, is initially stored temporarily in a store 60 via the grinding stock entry 59.
• the memory 60 has a memory sensor 61 with which the moisture content, the temperature and, if appropriate, the particle sizes of the hydrophilic polymer located in the memory 60 can be preferably determined.
• an outflow regulator 62 regulated as a process variable, the hydrophilic polymer from the reservoir 60 is introduced into an additive mixer 65, into which an additive located in an additive tank 63, usually a postcrosslinker or a mixture of several postings, is also located via an additive outflow regulator 64 controlled by a process variable - Crosslink, also entered in the additive mixer 65.
• the additive mixer 65 also has at least one additive mixer sensor 66 for determining process parameters of the mixer. Such process parameters are preferably the temperature and the mixing ratios of the hydrophilic polymer and the additives in the additive mixer 65.
• the additive mixer 65 is followed by a dryer 67 which has at least one dryer sensor 68. With regard to the functioning of the dryer, reference is made to the explanations regarding drying area 45.
• the further finishing area 7 adjoining the post-crosslinking area 6 has an auxiliary mixer 71, into which the hydrophilic polymer is introduced and to which a ripener 73 is connected.
• At least one, preferably more than two, auxiliary substances are introduced into the auxiliary substance mixer 71 from an auxiliary substance tank 69 via an auxiliary substance discharge regulator by means of a process variable and are not mixed with the hydrophilic polymer.
• Process variables of the auxiliary mixer are, in particular, the mixing or stirring speed of the stirring tools in the mixer, which can be expressed, for example, by the so-called Froud number.
• the mixture obtained in the auxiliary mixer 71 is subjected to a ripening process in the ripener 73, which can preferably also be a mixer or a dryer, which can be tracked by at least one ripening sensor 74 via corresponding process parameters, here again in particular the humidity and the temperature , If the processor 73 is a mixer, preferred process variables are the speed of the mixing units. If the ripener 73 is designed as a dryer, the above applies to the dryer as well. In the event that both the auxiliary mixer 71 and the ripener 73 have mixing units, a preferred process variable is the ratio of the mixing speeds of the stirring or mixing units in the auxiliary mixer 71 and in the ripener 73.
• the finished hydrophilic polymer is discharged via the product discharge 75 and filled into silos or other containers such as containers or big bags and transported away. Further details on the further packaging step and in particular on the ripening result from WO 2004/037900 AI, the content of which thus forms part of this disclosure.
• This model was coupled with the central control unit of the above-described manufacturing device on a pilot plant scale. At intervals of 10 minutes, process parameters and process variables from the process control system were automatically fed to the computer containing the artificial neural network and the expected experience parameter for the CRC was calculated at 36.6 g / g. An analytical check of the CRC on the hydrophilic polymer produced by these processes by the above-described manufacturing device showed a value of 36.2 g / g.
• Example 1 the procedure was analogous to that of Example 1, the difference from Example 1 being that the artificial neural network was used for
• Simulation of a planned change was used.
• the task was to going from a CRC of 33.5 g / g to set a CRC of 36 gg if possible without oversteering and uncontrolled the manufacturing device.
• the change in the flow rate for crosslinkers was first entered into the neural network until the latter calculated a CRC of 36.0 gg for a superabsorber produced in this way.
• the addition of crosslinking associated with the simulated CRC of 36.0 g / g was carried out in the production device and a super absorber was produced accordingly.
• An analytical examination of this superabsorbent showed a CRC of 36.2 g / g after the change in the amount of crosslinker took effect. A quick setting of the desired value was thus obtained without oversteering and understeering.
• FIG. 6 schematically shows an exemplary embodiment of a further processing machine, namely a core machine 77, by means of the “cores”, that is to say suction layers, with for example for baby diapers or women's bandages.
• core machines 77 can be wetlaid, drylaid, spunlaid, meltblown or air-laid machines (cf. article by Dr. Edgar Herrmann at EDANA 'S 1997 NORDIC NONWOVENS SYMPOSIUM with the title Premanufactured Airlaid Composites Containing Super absorbents).
• the core machine 77 is controlled via a computer-generated model implemented on a computer 2.
• the control is controlled by a neural network correspondingly programmed on the computer 2.
• the core machine 77 can in particular be part of a machine for producing baby diapers, which are sold by the companies Fameccanica, GDM, Diatec. Such a milling machine is described in more detail below with reference to FIG. 8.
• This machine for producing baby diapers is preferably controlled by the same computer-generated model implemented on the computer 2 as the core machine 77.
• the process parameters relevant for the production device 1 are in particular the process parameters specified above in connection with the production of a hydrophilic polymer.
• the process variables relevant for the production device 1 are in particular the process variables specified above in connection with the production of a hydrophilic polymer.
• the core machine 77 comprises a manufacturing device 1 for hydrophilic polymers.
• This manufacturing device 1 can in particular be controlled via a computer-generated model implemented on the same computer 2, particularly preferably via the same computer-generated model.
• a conventional control for the manufacturing device 1 is also possible and according to the invention.
• the core machine 77 further comprises a fiber supply 78, in which fibers, in particular cellulose fibers, are provided. In particular, these fibers can be unwound from coils or be scraped.
• these fibers can exist in pressed form on rolls and be unwound from them and defibrated by a hammer mill.
• the technique to be selected is determined, among other things, by the type of fluff.
• the fluff type thus represents a W process parameter.
• the fluff type depends on the type used and its manufacture.
• the type of fluff is determined by measurement methods typical of the cellulose industry.
• the fibers represent a first further processing component in the sense of the present invention.
• the fibers are transferred to a grinder 79 and comminuted there.
• the grinder 79 can be a conventional grinder, in particular it is a hammer mill.
• the W process parameters relevant for the grinder 79 include in particular the fiber length distribution generated by the grinder 79, the fiber lengths, the bulk density of the bulk material, the water content, fiber shape (stretched or convoluted) and / or the fill level of the grinder 79 or the fibers in the grinder 79, restoring forces, torques and the like due to the grinding process in and / or on the grinder 79.
• the W process parameters relevant to fiber preparation 78 include, in particular, the moisture, shape, bulk density and / or fiber length distribution of the fibers.
• the ground fibers are brought via a first feed line 80 into a mixer 81, into which the hydrophilic polymer is also introduced via a second feed line 82.
• the mixer 81 mixes the polymer with the fibers.
• Relevant W process parameters in the mixer 81 are, in particular, the air speed and / or turbulence in the mixer 81, the proportions of fibers and / or polymer added, the water content in the mixer 81, the dielectric constant and / or the adhesion or caking ability of the material to be mixed
• Relevant W process variables include in particular the mixing frequency, the increase or decrease in the addition of polymer and / or fibers, Transport speeds of the polymer and / or the fibers in the first 80 and / or the second feed line 82, etc.
• the mix is fed from the mixer 81 to the core former 84 via the delivery line 83.
• the core former 84 comprises a shaping drum 85 which, as shown schematically in detail in FIG. 7, has corresponding depressions 86 in which, for example, cores for diapers are formed. By rotating the former drum 85, cores are formed in the depressions 86, for example by centrifugal force or by applying a negative pressure.
• the core former 84 is operated in particular with negative pressure, preferably at pressures of less than 500 mbar, particularly preferably less than 100 mbar, in particular even less than 25 mbar, which represent the corresponding W process parameters and are generated by the suction power as a W process variable by the negative pressure Pumps can be set.
• the components 1, 78, 79, 81, 85 shown in FIG. 6 are controlled by the computer-generated model implemented on the computer 2.
• the model preferably at least one neural network, takes into account the process parameters and / or the W process parameters and evaluates the process variables and / or W process variables based on a wealth of experience.
• the data used also serve in particular to adapt the wealth of experience for future control and regulation processes.
• the process parameters and W process parameters can be monitored by appropriately trained measuring sensors, not shown.
• the individual components 1, 78, 79, 81, 85 are connected to the computer 2 via signal and control lines 91.
• a signal and control line 91 can be used, for example, for data from process sensors or W process parameter detectors to be recorded in the components.
• ten 1, 78, 79, 81, 85 are transferred to the computer, where they can be used, for example, as input signals to the neural network.
• Corresponding control signals which lead to changes in a process variable and / or a W process variable in components 1, 78, 79, 81, 85 can furthermore be transmitted from computer 2 to components 1, 78, 79, 81, 85.
• a plurality of signal and control lines 91 can be designed as a bus system, in which each component 1, 78, 79, 81, 85 is assigned a component-specific bus address.
• the signal and control lines 91 can at least partially be designed in the form of a wireless network (wireless LAN), optionally combined with a bus system.
• FIG. 8 schematically shows a further processing machine, namely a diaper manufacturing machine 88, comprising a core machine 77.
• the cores manufactured in the core machine according to one of the claims 77 leave the core machine 77 through the core former output line 87.
• the cores are provided with web, that is, surrounded with thin sheets (eg nonwovens). These webs can be connected to one another and / or to the core, in particular be integrally connected, in particular welded or glued, so that the web surrounds the cores, so that in particular the core is arranged essentially captively in a casing.
• these thin sheets are materials that form an acquisition layer for absorbing and passing on aqueous body fluids such as urine and a distribution layer for preferably evenly distributing the aqueous body fluids on the side of the diaper facing the wearer.
• aqueous body fluids such as urine
• a distribution layer for preferably evenly distributing the aqueous body fluids on the side of the diaper facing the wearer.
• the transitions between the individual layers and the core have a significant influence on the liquid management in the diaper or the feminine hygiene article (sanitary napkin).
• particular attention should be paid to the distances between the layers (acquisition layer followed by distribution layer) and the core and to connecting means such as adhesives or adhesives.
• the thickness of the structure obtained from the layers and the core as well as its weight per unit area and / or air permeability can be viewed.
• the roller pressures and or the amount of adhesive or glue in turn have an influence on these.
• the cores provided with web are further processed into diapers in the diaper former 90.
• the diaper former 90 in particular outer plastic sleeves of the diaper are built into which the core is molded.
• various other additional elements are connected to the diaper, such as. B. flexible waistbands, closures and / or flexible leg straps. Further details on the structure and functioning of a diaper machine include the contribution by Dr. Edgar Herrmann at EDANA'S 1997 NORDIC NONWOVENS SYMPOSIUM entitled Premanufactured Airlaid Composites Containing Superabsorbents.
• Coreformer 77, web applicator 89 and diaper former 90 are connected to the computer 2 via signal and control lines 91.
• the control or regulation of the components 77, 89, 90 takes place via a computer-generated model implemented on the computer 2, in particular a neural network.
• the relevant W process parameters, process parameters, W process variables and / or process variables are recorded and, if necessary, adapted via the neural network.
• Relevant process parameters for the web applicator 89 are, in particular, the feed speed of the web, the amount of adhesive, viscosity, temperature, joining conditions, etc.
• Relevant process parameters for the diaper former 90 are, for example, amounts of adhesive, viscosity, temperatures, etc.
• FIG. 9 schematically shows a paper machine 92 which comprises a head box 93 followed by a drainage and drying area 94.
• a paper pulp is essentially produced from cellulose material, water and suitable additives such as flocculants and the like. These represent further processing components in the sense of the present invention.
• hydrophilic polymers are added in a mixing area. These can be generated in particular in a manufacturing device 1.
• the polymer produced by means of such a paper machine 92 Comprehensive papers include, in particular, toilet, kitchen and / or maintenance papers, as well as handkerchiefs.
• the addition of the hydrophilic polymer can also take place in the paper pulp which has already been applied extensively for dewatering.
• W process parameters relevant for paper production include in particular the length of the cellulose fibers and / or their length distribution, the water content of the paper pulp, the viscosity and / or temperature of the paper pulp, the present pH value, the size and / or shape of the polymer particles (polymer particles and / or fibers), the size distribution of the polymer particles, swelling and / or adsorption speed of the polymer particles.
• W process variables relevant for paper production include, in particular, the additions (amount and / or speed) of additives, for example flocculants, acidulants or alkalis, the dewatering speed, heating power and / or the pressure conditions, in particular in the dewatering and drying area, time and speed of addition of the polymer, the adjustable concentration ratios, in particular the polymer, fiber, water and / or additive concentration and their ratios.
• the W process variables and W process parameters in the incorporation of hydrophilic polymer in the production of paper having hydrophilic polymer are to be set so that the polymer absorbs as little water as possible during the production, so that the polymer containing paper after it Production is as homogeneous as possible and has a high suction and retention capacity.
• the paper machine 92 and or the manufacturing device 1 are controlled and / or regulated by a computer-generated model, in particular at least one corresponding neural network.
• the connection of the paper machine 92 and / or the manufacturing device 1 to a computer on which the at least one computer-generated model is implemented is via signal lines 91.
• 10 schematically shows a fiber production device 95 for producing cellulose fibers comprising hydrophilic polymers, as described, inter alia, in WO 03/012182 A1.
• a spinning preparation 96 for example, cellulose precursors, for example a substituted pulp, in particular carboxymethylated pulp, are broken down (lye and carbon disulphide treatment) and placed in a spinning solution (cf. for example DE 28 09 312 AI).
• Hydrophilic polymers which can be produced in particular in a production device 1, are incorporated into this spinning solution.
• the spinning solution obtained in this way is spun into fibers in a spinning device 97, which are aftertreated in a fiber aftertreatment unit 98, in particular washed and / or dried.
• the cellulose precursors and the digestion, dissolving and / or auxiliary agents used are further processing components within the meaning of the present invention.
• the fiber production device 95 is preferably controlled or regulated by a computer-generated model which is implemented on the computer 2.
• the W process parameters relevant for the spinning preparation 96, the spinning device 97 and the fiber post-treatment unit 98 include in particular the degree of substitution of the pulp, the pH value, the temperature, the concentration ratios such as the sulfur content or further concentrations of components of the spinning solution and / or the viscosity of the spinning solution, the size and / or shape of the polymer particles (polymer particles and / or fibers), the size distribution of the polymer particles, swelling and / or adsorption rate of the polymer particles, the flow rate, the mass flow rate and / or the shear on or through the Spinneret, the degree of stretching and / or the titer of the fibers.
• the W process variables relevant for the spinning preparation 96, the spinning device 97 and the fiber post-treatment unit 98 include in particular the basification and sulfidation of the spinning solution, the spinning pressure, the spinning speed, the removal speed of the fibers leaving the nozzle, heating outputs, amount of a washing medium to be added, mixing fre- quenz, mixer geometry, time of mixing in particular the admixture of the hydrophilic polymer to the spinning solution.
• the W process variables are especially adjusted so that there is a uniform spinning process in which in particular the spinneret (s) do not become clogged and that the most homogeneous distribution of the hydrophilic polymer articles in the cellulose fiber is achieved.
• a paper produced by means of the paper machine 92 shown in FIG. 9 and described above and / or a product comprising the fiber produced by means of the fiber production machine 95 shown in FIG. 10 and described above or such fibers can be used in particular in the manufacture of cores and / or diapers represent a further processing component in the sense of the present invention and are used in the core machine 77 and / or diaper machine 88. It is preferred here that the neural networks communicate with at least one of the further processing devices according to FIG.
• the neural network controlling the diaper machine 88 or the core machine 77 in particular defined interfaces, preferably at least one common neuron, or that there is a common neural network Network is present which controls or regulates at least two of the processing machines 77, 88, 92, 95 and / or manufacturing devices 1 and / or parts thereof described above.

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