Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
  • C08G63/78—Preparation processes
  • C08G63/80—Solid-state polycondensation
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
  • C08G63/78—Preparation processes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B9/00—Making granules
  • B29B9/12—Making granules characterised by structure or composition
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B9/00—Making granules
  • B29B9/16—Auxiliary treatment of granules
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
  • C08G63/78—Preparation processes
  • C08G63/785—Preparation processes characterised by the apparatus used
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
  • C08G69/02—Polyamides derived from amino-carboxylic acids or from polyamines and polycarboxylic acids
  • C08G69/04—Preparatory processes
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
  • C08G69/02—Polyamides derived from amino-carboxylic acids or from polyamines and polycarboxylic acids
  • C08G69/04—Preparatory processes
  • C08G69/06—Solid state polycondensation
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
  • C08G69/02—Polyamides derived from amino-carboxylic acids or from polyamines and polycarboxylic acids
  • C08G69/26—Polyamides derived from amino-carboxylic acids or from polyamines and polycarboxylic acids derived from polyamines and polycarboxylic acids
  • C08G69/28—Preparatory processes
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
  • C08G69/02—Polyamides derived from amino-carboxylic acids or from polyamines and polycarboxylic acids
  • C08G69/26—Polyamides derived from amino-carboxylic acids or from polyamines and polycarboxylic acids derived from polyamines and polycarboxylic acids
  • C08G69/28—Preparatory processes
  • C08G69/30—Solid state polycondensation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B9/00—Making granules
  • B29B9/16—Auxiliary treatment of granules
  • B29B2009/165—Crystallizing granules
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B9/00—Making granules
  • B29B9/16—Auxiliary treatment of granules
  • B29B2009/168—Removing undesirable residual components, e.g. solvents, unreacted monomers; Degassing
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B9/00—Making granules
  • B29B9/02—Making granules by dividing preformed material
  • B29B9/06—Making granules by dividing preformed material in the form of filamentary material, e.g. combined with extrusion

Definitions

• the invention relates to a method for producing a partially crystalline polycondensate, in particular a polyester or polyamide, with the following steps:
• WO 01/42334 (Schiavone) describes a process which optimizes PET production in such a way that a preform (preform) with improved properties can be produced, which is achieved by using a high proportion of comonomer.
• the particle manufacturing process has not been optimized and the possibility of creating improved properties through the correct choice of particle size is not recognized.
• the process is limited to polyethylene terephthalate with a high copolymer content, which on the one hand has a negative influence on the treatment in the SSP and on the other hand limits the area of application of the PET produced in this way.
• step b) granules with an average diameter of 0.4-1.7 mm, in particular of 0.6-1.2 mm, are preferably formed.
• the polycondensate prepolymer melt can be pressed through a nozzle plate with a plurality of nozzle holes, which are preferably arranged on at least one ring track.
• Cutting in the granulation step b) can be carried out using a rotating knife.
• the cutting in the granulation step b) is preferably carried out by means of a fluid jet, in particular by means of a liquid jet.
• the polyester is a polyethylene terephthalate, a polybutylene terephthalate, a polyethylene naphthalate or one of their copolymers.
• the polycondensate prepolymer melt is preferably a polyester melt, in particular the melt of a polyethylene terephthalate or one of its copolymers with a degree of polymerization analogous to an IV value of 0.18 to 0.45 dl / g.
• the prepolymer granules preferably have a crystallinity of less than 10% on entering crystallization step c).
• the crystallization step c) can take place in a fluidized bed or fluidized bed reactor under the action of a fluidizing gas.
• the average temperature of the prepolymer granules (in ° C.) in the transition from the granulation step b) to the crystallization step c) is preferably not allowed to fall below a value of 1/4 of the melting temperature Tm Pr p (in ° C.).
• a liquid can be used for cutting, which is largely separated from the prepolymer granules before they are fed to the crystallization step c), water in particular being used as the liquid.
• the polycondensate can be a copolymer of polyethylene terephthalate, the dicarboxylic acid component consisting of more than 96 mol% of terephthalic acid and the diol component consisting of more than 94 mol% or less than 84 mol% Ethylene glycol exists.
• the polycondensate can be a copolymer of polyethylene terephthalate, the diol component consisting of more than 98 mol% of ethylene glycol.
• the polycondensate can be a copolymer of polyethylene terephthalate, the dicarboxylic acid component consisting of 96 mol% to 99 mol% of terephthalic acid.
• Heating to a suitable temperature for solid-phase polycondensation is preferably carried out simultaneously with the crystallization step c).
• Porous granules can also be produced by adding a blowing agent to the prepolymer melt, preferably in step a) and / or in step b).
• the polycondensate is a crystallizable, thermoplastic polycondensate, such as, for example, polyamide, polyester, polycarbonate or polylactide, which is obtained by a polycondensation reaction with the elimination of a low-molecular reaction product.
• the polycondensation can take place directly between the monomers or via an intermediate stage which is then reacted by transesterification, the transesterification again being able to take place with the elimination of a low molecular weight reaction product or by ring opening polymerization.
• the polycondensate obtained in this way is essentially linear, and a small number of branches can arise.
• Polyamide is a polymer which is obtained by polycondensation from its monomers, either a diamine component and a dicarboxylic acid component or a bifunctional monomer with an amine and a carboxylic acid end group.
• Polyester is a polymer which, through polycondensation, consists of its monomers, a diol component and a dicarboxylic acid component. is won. Different, mostly linear or cyclic diol components are used. Different, mostly aromatic dicarboxylic acid components can also be used. Instead of the dicarboxylic acid, its corresponding dimethyl ester can also be used.
• polyesters are polyethylene terephthalate (PET), polybutylene terephthalate (PBT) and polyethylene naphthalt (PEN), which are used either as homopolymers or as copolymers.
• PET polyethylene terephthalate
• PBT polybutylene terephthalate
• PEN polyethylene naphthalt
• the polyester consists of a copolymer of polyethylene terephthalate, either:
• the diol component consists of ethylene glycol, or
• the dicarboxylic acid component consists of more than 96 mol% of terephthalic acid and the diol component consists of more than 94 mol% or less than 84 mol% of ethylene glycol, or
• the dicarboxylic acid component consists of 96 mol% to 99 mol% of terephthalic acid.
• the polycondensate monomers are polymerized or polycondensed into a prepolymer in the liquid phase.
• the prepolymer melt is usually prepared in a continuous process, an esterification stage being followed by a prepolycondensation stage.
• the polycondensation stages used in the conventional polyester manufacturing process in the high-viscosity reactor also called finisher
• do not take place see: Modern Polyesters, Wiley Series in Polymer Science, Edited by John Scheirs, J. Wiley & Sons Ltd, 2003; Figure 2.37).
• the degree of polymerization (DP) achieved is still significantly below the degree of polymerization of the polycondensate after the subsequent solid phase treatment.
• the degree of polymerization of the prepolymer is usually below 60%, in particular below 50%, of the degree of polymerization of the polycondensation post-condensed in the solid phase. sates.
• the degree of polymerization of the prepolymer is preferably between 10 and 50, in particular between 25 and 40.
• the process usually takes place at an elevated temperature, as a result of which the prepolymer is obtained as a prepolymer melt.
• the prepolymer melt can also be generated by melting a previously solidified prepolymer. Mixtures of various prepolymers can also be used as prepolymer melt, and recycled raw materials can also be used.
• the prepolymer melt can contain various additives, such as, for example, catalysts, stabilizers, coloring additives, reactive chain extension additives, etc.
• the prepolymer melt is pressed through a nozzle with a large number of openings and then cut.
• the nozzle preferably consists of at least one nozzle body and a nozzle plate.
• the prepolymer melt is distributed in the nozzle body over the surface of the nozzle plate in which the openings are located, measures being taken for uniform distribution, temperature control and flow rate.
• opening lengths In order to compensate for irregularities when flowing through the openings, it may be advantageous to use different opening lengths and depending on the position of the openings To provide opening diameter.
• the openings can be widened on the inlet side. A straight cut edge on the exit side is advantageous, with a widening and / or rounding of the opening being conceivable here as well.
• the nozzle plate must be sufficiently heated (e.g. electrically or with a heat transfer medium) to prevent the prepolymer melt from freezing and thus blocking the openings.
• the outside of the nozzle should be insulated in order to reduce heat flow.
• the nozzle plate can e.g. made of metal, ceramic or a combination of metal and ceramic.
• the openings are usually round, but can also represent a different profile, such as slot-shaped openings.
• the resulting granules are, for example, spherical or spherical, lenticular or cylindrical. Porous granules are also conceivable, for example if a blowing agent (gas or gas-generating chemical blowing agent) is added to the prepolymer melt.
• a blowing agent gas or gas-generating chemical blowing agent
• the size of the granules should, according to the invention, be less than 2 mm, preferably 0.4-1.7 mm, in particular 0.6-1.2 mm.
• the cutting should take place at the nozzle outlet.
• a circumferential cutting device such as a rotating cutter head can be used for cutting.
• One or more cutting elements are attached to the cutter head, which separate the prepolymer melt emerging from the nozzle openings. There may be a small distance between the nozzle plate and the cutting elements in order to prevent the cutting elements from constantly being “ground” on the nozzle plate.
• the cutting elements can be made from different materials, such as, for example, metal, glass or ceramic, although metal knives are preferred .
• the cutting can also be carried out by one or more fluid jets or liquid jets under high pressure (water jet cutting system, jet cutting).
• an abrasive cutting agent can be added.
• a combination of gas jet and liquid jet can also be used as a cutting "mixed fluid jet”.
• the granulate can also be made by using one or more laser beams (laser beam cutting or laser cutting).
• the number of holes and the cutting frequency must be adapted depending on the throughput of the desired granule size, the cutting frequency being able to be many times higher than the rotational frequency of the cutting device through the use of several cutting elements.
• the following table shows the resulting strong dependency:
• the cut granules are immediately surrounded by a liquid.
• the granulation can take place in the liquid or the granules can be thrown into a liquid ring.
• Suitable granulation devices are known under the names “head granulation” or “hot face granulation”, “underwater granulation” and “water ring granulation” Despite the use of the term “water” in the designation of the granulation devices, other fluids, fluid mixtures, liquids, liquid mixtures or liquids with dissolved, emulsified or suspended substances can also be used.
• the fluid or the liquid is usually guided at least partially in a circuit in which the conditions (temperature, pressure, composition) for renewed use for granulation are maintained.
• the polycondensate melt is solidified by the cooling. This is preferably done by the liquid used in the granulation process. However, the use of additional cooling media or the combination of several cooling media is conceivable.
• the cooling can take place to a temperature which is below the glass transition temperature of the polycondensate, which allows the granules to be stored and / or transported over a longer period of time.
• the average temperature of the pre-condensate granules can also be kept at a higher level in order to improve the energy efficiency of the process. For this purpose, it is possible to raise the temperature of the cooling medium and / or to select a correspondingly short residence time in the cooling medium (less than 5 seconds, in particular less than 2 seconds).
• the average granule temperature (in ° C.) should be above 1/4 Tm Pr p, in particular above 1/3 Tmp rP , where Tm Pr p denotes the melting temperature (in C C) of the polycondensate prepolymer.
• At least partial crystallization can take place while the prepolymer granules are in contact with the liquid.
• the contact conditions (temperature and time) between the prepolymer granules and the liquid are preferably selected such that there is no significant impairment of the reaction rate in the subsequent solid-phase polycondensation process.
• the contact time of a PET prepolymer in water, at a temperature between 1 and 25 ° C below the boiling point should not be more than 10 minutes, preferably not more than 2 minutes.
• An embodiment of the present invention provides that the contact conditions are selected such that the degree of crystallization of the prepolymer granules is less than 10% before entering the subsequent crystallization step.
• the degree of crystallization of the prepolymer granules is increased by the methods known in the prior art.
• the prepolymer granules must be treated at a suitable crystallization temperature. Crystallization should at least achieve a degree of crystallization that allows treatment in the subsequent solid-phase polycondensation, without sticking or clumping, and which is significantly higher than the degree of crystallinity of the polycondensate cooled by quenching.
• the temperature range for PET is between 100 and 220 ° C., and a degree of crystallization of at least 20%, preferably of at least 30%, is achieved.
• the granules can be brought to a temperature outside the crystallization temperature range. Cooling to a temperature below the crystallization range should, however, preferably be avoided. If the temperature of the prepolymer granules is below the suitable crystallization temperature after they have been separated from the liquid used in the granulation process, the prepolymer granules must be heated. This can be done, for example, via a heated wall of the crystallization reactor, via heated internals in the crystallization reactor, by radiation or by blowing in a hot process gas.
• the suitable crystallization time results from the time to heat the product to the crystallization temperature, plus at least the crystallization half-life at the given temperature, preferably 2 to 20 half-lives being added to the heating-up time in order to achieve a sufficient mixing between crystalline and amorphous product.
• Particularly suitable crystallization reactors are fluidized bed or fluidized bed crystallizers, since these do not tend to form dust.
• any residues of the liquid are also removed from the granulation process.
• the molecular weight of the polycondensate granules is brought to a higher degree of polymerization by solid-phase polycondensation, with at least a 1.67-fold, in particular at least a 2-fold increase in the degree of polymerization.
• the IV value is increased to at least 0.6dl / g, usually to at least 0.7dl / g.
• the solid-phase polycondensation takes place according to the methods known in the prior art and comprises at least the steps of heating to a suitable post-condensation temperature and the post-condensation reaction. Further steps for the previous crystallization or subsequent cooling can optionally be carried out. Both continuous and batch processes can be used, e.g. in apparatus such as fluidized bed, bubble bed or fixed bed reactors as well as in reactors with stirring tools or self-moving reactors such as rotary kilns or tumble dryers.
• the solid phase polycondensation can take place at normal pressure, at elevated pressure or under vacuum.
• mp is the sum of all product flows fed into the process
• mg is the sum of all gas flows fed into the process.
• Air or inert gases such as nitrogen or CO 2 as well as mixtures of process gases are suitable as process gases.
• the process gas can contain additives which either reactively act on the product to be treated or are passively deposited on the product to be treated.
• the process gas is preferably conducted at least partially in a circuit.
• the process gas can be cleaned of undesired products, in particular cleavage products of the polycondensation reactions.
• Typical fission products such as water, diols (e.g. ethylene glycol, butanediol), diamines or aldehydes (e.g. acetaldehyde) should be reduced to values below 100ppm, in particular to values below 10ppm.
• the cleaning can be carried out by gas cleaning systems known in the prior art, such as, for example, catalytic combustion systems, gas scrubbers, adsorption systems or cold traps.
• the suitable post-condensation temperature lies in a temperature range which is limited by a minimum reaction rate of the polycondensate and which is limited by a temperature which is slightly below the melting temperature of the polycondensate.
• the minimum reaction rate is the rate at which the desired increase in the degree of polymerization can be achieved in an economically justifiable period of time.
• the post-condensation is in the range of 190 ° C to 245 C C.
• the polycondensation conditions should be chosen so that the granules then under mild conditions as possible to a final product can be processed.
• the corresponding relationships for PET production are explained, for example, in the application PCT / CH03 / 00686, which is hereby included.
• the suitable post-condensation time is in the range from 2 to 100 hours, with residence times of 6 to 30 hours being preferred for economic reasons.
• the step of crystallization and the step of heating to a suitable post-condensation temperature can take place simultaneously or at least in the same reactor, wherein the reactor used for this can be separated into several process chambers in which different process conditions (e.g. temperature and residence time) can prevail. It is advantageous if the heating rate at which the polycondensate is heated to the post-condensation temperature range is sufficiently large to prevent excessive crystallization before the polycondensation reaction begins. For PET, the heating rate should be at least 10 ° C / min, preferably at least 50 ° C / min.
• the polycondensates can be processed into various products such as fibers, tapes, foils or injection molded parts.
• PET is largely processed into hollow objects such as bottles.

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• Chemical & Material Sciences (AREA)
• Polymers & Plastics (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Organic Chemistry (AREA)
• Mechanical Engineering (AREA)
• Engineering & Computer Science (AREA)
• Polyesters Or Polycarbonates (AREA)
• Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
• Polyamides (AREA)
• Other Resins Obtained By Reactions Not Involving Carbon-To-Carbon Unsaturated Bonds (AREA)
• Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)

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• 2004
  • 2004-03-12 DE DE102004012579A patent/DE102004012579A1/de not_active Withdrawn
• 2005
  • 2005-01-24 US US10/590,554 patent/US20070135613A1/en not_active Abandoned
  • 2005-01-24 CN CNA2005800079510A patent/CN1930209A/zh active Pending
  • 2005-01-24 WO PCT/CH2005/000035 patent/WO2005087838A1/de active Application Filing
  • 2005-01-24 JP JP2007502164A patent/JP2007528920A/ja active Pending
  • 2005-01-24 EP EP05700330A patent/EP1735367A1/de not_active Withdrawn
  • 2005-01-24 KR KR1020067019837A patent/KR20070012383A/ko not_active Application Discontinuation
  • 2005-01-24 BR BRPI0508679-5A patent/BRPI0508679A/pt not_active IP Right Cessation
  • 2005-01-24 EA EA200601680A patent/EA009454B1/ru not_active IP Right Cessation
• 2006
  • 2006-08-16 ZA ZA200606797A patent/ZA200606797B/xx unknown

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