DE1629423A1 - Process for the production of synthetic resin foams and use of a pipe produced by this process - Google Patents

Process for the production of synthetic resin foams and use of a pipe produced by this process

Info

Publication number
DE1629423A1
DE1629423A1 DE19661629423 DE1629423A DE1629423A1 DE 1629423 A1 DE1629423 A1 DE 1629423A1 DE 19661629423 DE19661629423 DE 19661629423 DE 1629423 A DE1629423 A DE 1629423A DE 1629423 A1 DE1629423 A1 DE 1629423A1
Authority
DE
Germany
Prior art keywords
foam
strand
synthetic resin
resin foams
tube
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
DE19661629423
Other languages
German (de)
Inventor
Dipl-Chem Dr Hans Eberle
Dipl-Ing Joseph Schirmeisen
Gerhard Wuttke
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Saint Gobain Isover G+H AG
Original Assignee
Gruenzweig und Hartmann AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Gruenzweig und Hartmann AG filed Critical Gruenzweig und Hartmann AG
Publication of DE1629423A1 publication Critical patent/DE1629423A1/en
Pending legal-status Critical Current

Links

Classifications

    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02B—HYDRAULIC ENGINEERING
    • E02B11/00—Drainage of soil, e.g. for agricultural purposes
    • E02B11/005—Drainage conduits
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
    • B29C44/34—Auxiliary operations
    • B29C44/36—Feeding the material to be shaped
    • B29C44/46—Feeding the material to be shaped into an open space or onto moving surfaces, i.e. to make articles of indefinite length
    • B29C44/50—Feeding the material to be shaped into an open space or onto moving surfaces, i.e. to make articles of indefinite length using pressure difference, e.g. by extrusion or by spraying
    • B29C44/507—Feeding the material to be shaped into an open space or onto moving surfaces, i.e. to make articles of indefinite length using pressure difference, e.g. by extrusion or by spraying extruding the compound through an annular die
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
    • B29C44/34—Auxiliary operations
    • B29C44/56—After-treatment of articles, e.g. for altering the shape
    • B29C44/5627—After-treatment of articles, e.g. for altering the shape by mechanical deformation, e.g. crushing, embossing, stretching
    • B29C44/5663—After-treatment of articles, e.g. for altering the shape by mechanical deformation, e.g. crushing, embossing, stretching by perforating the foam, e.g. to open the cells
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/001—Combinations of extrusion moulding with other shaping operations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/09—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/09—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
    • B29C48/10—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels flexible, e.g. blown foils
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/13—Articles with a cross-section varying in the longitudinal direction, e.g. corrugated pipes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C55/00—Shaping by stretching, e.g. drawing through a die; Apparatus therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
    • B29K2105/04—Condition, form or state of moulded material or of the material to be shaped cellular or porous
    • B29K2105/045—Condition, form or state of moulded material or of the material to be shaped cellular or porous with open cells
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2023/00—Tubular articles
    • B29L2023/005—Hoses, i.e. flexible
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2031/00—Other particular articles
    • B29L2031/14—Filters

Description

Verfahren zur Herstellung von Kunstharz-Schaumstoffen und Verwendung eines nach diesem Verfahren gefertigten Rohres.Process for the production of synthetic resin foams and use a pipe manufactured according to this process.

Die Erfindung betrifft ein Verfahren zur kontinuierlichen Herstellung von Kunstharzschaumstoffen in Schnecken-Strangpressen, in m die zu behandelnden Kunststoffe und ggfs.The invention relates to a process for continuous production of synthetic resin foams in screw extrusion presses, in m the size to be treated Plastics and possibly

Schäumungshilfsmittel in einer Schneckenzone verminderten Druckaufbaus granuliert, mit einem Treibmittel gemischt und anschlieEend in ein nachgeschaltetes Schneckenteil mit erneutem Druckaufbau geführt werden, nach Patent.Foaming aid in a screw zone with reduced pressure build-up granulated, mixed with a propellant and then in a downstream Screw part can be guided with renewed pressure build-up, according to patent.

(Aktenzeichen G 45 457 X/39a3). ffiberraschenderweise hat sich bei der Herstellung von Kunstharzsehaumstoffen nach der Hauptanmeldung gezeigt, daß nach dem dort beschriebenen Verfahren offenzellige Kunstschäume nahezu beliebiger Porositätsgrade kontinuierlich gefertigtverden können, wenn bestimmte Verfahrensbedingungen eingehalten werden.(File number G 45 457 X / 39a3). ffsurprisingly, at the production of synthetic resin foams according to the parent application shown that by the process described there, open-cell artificial foams can be almost any Porosity grades can be manufactured continuously if certain process conditions are met be respected.

Erfindungsgemäß bestehen diese Verfahrenabedingungen in der definierten Einstellung der Abzugsgeschwindigkeit des aus der Düse austretenden Schaumstoffßtrangea sowie des Gasdruckes des in der Zone verminderten Druckaufbaus des Extruders dem Material aufgedrückten Treibmittelgases. Es wurde hierbei gefunden, daß der Porositätsgrad des auf diese Weise hergestellten Schaumstoffes mit steigendem Gasdruck anwächst.According to the invention, these process conditions are defined as follows Adjustment of the withdrawal speed of the foam strand emerging from the nozzle as well as the gas pressure of the pressure build-up of the extruder which is reduced in the zone material forced propellant gas. It was found here that the degree of porosity of the foam produced in this way with increasing Gas pressure increases.

So konnten beispielsweise bei .einem weichmacherfreien PVC-Ansatz unter Verwendung von Stickstoff als Treibmittel allein durch eine Erhöhung des Gasdruckes von 22 auf 25 atü bei einer konstanten Abzugsgeschwindigkeit des Schaumstoffmaterials von 210 (cr.-s/min), Rohre hergestellt werden, deren Porositätsgrad um den Faktor "Zehn" höher lag als der der Rohre, die vor der Druckerhöhung produziert worden waren.For example, with a plasticizer-free PVC approach using nitrogen as a propellant solely by increasing the gas pressure from 22 to 25 atm with a constant take-off speed of the foam material of 210 (cm.-s / min), pipes can be produced whose degree of porosity is increased by the factor "Ten" higher than that of the pipes that were produced before the pressure increase was.

Als Porositätsgrad wurde die Luftmenge definiert, die während einer festgesetzten Zeitspanne bei konstanter Druckdifferenz durch eine Normfläche strömt. Im Falle von Schaumstoffrohren wurden der Messung gleiche Rohrabmessungen zugrundegelegt und als Porositätsgrad die Luftmenge in m3,, definiert, die bei einer Druckdifferenz von 200 mm Wassersäule zwischen Innenrohrraum und Außenraum den Rohrmantel pro Stunde durchströmt.The degree of porosity was defined as the amount of air that was released during a a fixed period of time flows through a standard surface at a constant pressure difference. In the case of foam pipes, the measurement was based on the same pipe dimensions and the degree of porosity is defined as the amount of air in m3 ,, which occurs at a pressure difference of 200 mm water column between the inner pipe space and the outer space the pipe jacket per hour flows through.

Weitere Parameter, die den Porositätsgrad des aufgeschäumten Materials bestimmen sind die Abzugsgeschwindigkeit des aus der Extruderdüse austretenden Schaumstroffstranges sowie die Art des formgebenden Kalibriervorganges.Other parameters that determine the degree of porosity of the foamed material what is determined is the take-off speed of the strand of foam extruded from the extruder nozzle as well as the type of shaping calibration process.

Bei freigeschäumten Strängen ist im allgemeinen die erreichbare Porosität am größten. Lurch den Einsatz einer an sich bekannten Vakuum-Kalibriereinrichtung tritt jedoch eine mehr oder weniger starke Glättung der äußeren Schaumstoffoberfläche und damit ein Verschluß der äußeren Zellen auf, wodurch die Porosität der Rohrwandung abnimmt. Durch eine Erhöhung der Abzugsgeschwindigkeit des aus der Extruderdüse austretenden Stranges kann dieser Effekt zugunsten einer Vergrößerung der Porosität in bestimmten Grenzen wieder rückgängig gemacht werden.In the case of free-foamed strands, the porosity that can be achieved is generally the biggest. By using a vacuum calibration device known per se However, a more or less strong smoothing of the outer foam surface occurs and thus a closure of the outer cells, whereby the porosity of the pipe wall decreases. By increasing the take-off speed from the extruder nozzle exiting strand, this effect can favor an increase in the porosity can be reversed within certain limits.

Beispielsweise konnte unter den oben angegebenen sonst-gleichen Extrusionsbedingungen durch eine-Erhöhung der Abzugsgeschwindigkeit des Schaumstoffrohres von 180 (cm/min) auf 210 (cm/min) der Porositatsgrad der Rohrwandung etwa um einen Faktor"Pünf" vergrößert werden.For example, under the otherwise identical extrusion conditions specified above by increasing the withdrawal speed of the foam tube by 180 (cm / min) to 210 (cm / min) the degree of porosity of the pipe wall is increased by about a factor of "five" will.

Um auch bei stärker kalibrierten Schaumstoffsträngen eine definierte Porosität zu erhalten, kann in Weiterführung der Erfindung -die Oberfläche eines aus. dem Extruder austretenden Schaumstoffstranges, -rohres od.dgl.im plastischen Zustand durch einen Abzug, dessen Backen mit Nadeln versehen sind, gelocht und das material gefördergt werden.In order to have a defined To obtain porosity, can in continuation of the invention -the surface of a the end. the extruder exiting foam strand, pipe or the like in plastic State by a trigger, the jaws of which are provided with needles, punched and that material to be conveyed.

Im Fall, daß nur bestimmte Teile der Schaumstoffoberfläche strömungsdurchlässig ausgestaltet werden sollen, ist es in weiterer Ausbildung der Erfindung möglich, den gebildeten Schaumstoffstrang, -rohr odedgl. nur jeweils im Bereich eines Segments parallel zur Strang- bzw. Rohrachse oberflächlich mit lochungen zu versehen und damit bestimmten Teilen unterschiedliche Durchlässigkeiten für flüssige oder. gasförmige Medien zu verleihen.In the event that only certain parts of the foam surface are flow-permeable are to be designed, it is possible in a further embodiment of the invention, the formed foam strand, tube or the like. only in the area of one segment to be provided with perforations on the surface parallel to the strand or pipe axis and thus certain parts have different permeabilities for liquid or. gaseous To lend media.

Bei Drainagerohren ist es z.B. erwünscht, daß nur die bei der Verlegung nach oben gerichtete Rohrwandung porös ausgebildet ist, auf eine Lochung der unteren Qberfläche des Rohrmantesl kann damit in diesem Fall verzichtet werden Über das beanspruchte Verfahren hinaus begehrt die erfindung weiterhin Schutz für die Verwendung von insbesondere nach Anspruch 1 bis 3 oder nach dem Hauptpatent hergestellten offenzelligen Kunstharz-Schaumstoffplatten, -rohre u. dgl als Filter für Gas- und/oder Plüssigkeiten sowie als drainage oder Belüftungsrohr bzw. als Rohr zu biologischen Reinigung von Klarschlamm od.dgl.In the case of drainage pipes, for example, it is desirable that only those during laying upwardly directed pipe wall is porous, on a perforation of the lower The surface of the pipe jacket can therefore be dispensed with in this case In addition to the claimed processes, the invention continues to seek protection for use of open-celled ones produced in particular according to claims 1 to 3 or according to the main patent Synthetic resin foam sheets, pipes and the like as filters for gas and / or fluids as well as drainage or ventilation pipe or as a pipe for biological purification of Clear sludge or the like.

Claims (2)

P a t e n t a n s p r ü c h e 1) Verfahren zur kontinuierlichen Herstellung von Kunstharz-Schaumstoffen in Schneckenstrangpressen nach Påtent....P a t e n t a n s p r ü c h e 1) Process for continuous production of synthetic resin foams in screw extrusion according to Påtent ... (Aktenzeichen G 45 457 X/39a3r), dadurch g e k e- n n z e i c h n e t, daß durch definierte Binstellungen der Abzugsgeschwindigkeit des aus der Düse austretenden Schaumstoffstranges sowie des Gasdrucks in der Zone verminderten Druckaufbaus des Extruders offenzellige Kunstharzschaumstoffe vorbestimmbaren Porositätsgrades hergestellt werden. (File number G 45 457 X / 39a3r), thus g e k e n n z e i c h n e t that by defining the withdrawal speed of the from the nozzle escaping foam strand and the gas pressure in the zone of reduced pressure build-up of the extruder open-cell synthetic resin foams with a predeterminable degree of porosity getting produced. 2) Verfahren nach Anspruch 1, dadurch g e k e n n- z e i c h n e t, daß die Oberfläche des aus der Extruderdüse austretenden Schaumstoffstranges, -rohres od.dgl. im plastischen Zus-tand unter Verwendung einer ggfs. heiz- oder/und kühlbaren Kalitriervorrichtung unter Verschluß ihrer Zellen geglättet und anschließend das Schaumstoffmaterial durch einen Abzug, dessen Backen mit Nadeln versehen sind, gelocht und gefördert wird, 3) Verfahren nach Anspruch 2, dadurch g e k e n n z e i c h n e t, daß ein Schaumstoffstrang,-rohr od.dgl. nur jeweils im Bereich eines Segmentes parallel zur Strang- bzw. Rohrachse gelocht wird.2) Method according to claim 1, characterized in that g e k e n n- z e i c h n e t, that the surface of the foam strand or tube emerging from the extruder nozzle or the like. in the plastic state using a possibly heatable and / or coolable Kalitriervorrichtung smoothed with the closure of their cells and then the Foam material punched through a trigger, the jaws of which are provided with needles and is funded, 3) Method according to Claim 2, characterized in that it is possible to use it n e t that a foam strand, tube or the like. only in the area of one segment is punched parallel to the strand or pipe axis. +) Verwendung eines insbesondere nach Anspruch 1 bis 3 oder nach dem Hauptpatent hergestellten offenzelligen Schaumstoffrohres für-Filter- und Drainagezweche oder zur biologischen Abwasserreinigung (Belüftung von Klärschlammbecken u.dgl.).+) Use of a particular according to claim 1 to 3 or according to the Main patent manufactured open-cell foam tube for filter and drainage purposes or for biological wastewater treatment (ventilation of sewage sludge basins, etc.).
DE19661629423 1966-04-02 1966-04-02 Process for the production of synthetic resin foams and use of a pipe produced by this process Pending DE1629423A1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEG0046497 1966-04-02

Publications (1)

Publication Number Publication Date
DE1629423A1 true DE1629423A1 (en) 1971-01-14

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DE19661629423 Pending DE1629423A1 (en) 1966-04-02 1966-04-02 Process for the production of synthetic resin foams and use of a pipe produced by this process

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2369919A1 (en) * 1976-11-05 1978-06-02 Bayer Ag Extrusion of thermoplastics as microporous foamed profiles - e.g. for irrigation etc., using high extrusion temp. and blowing agent contents
EP0078108A2 (en) * 1981-10-22 1983-05-04 Imperial Chemical Industries Plc Production of PVC irrigation pipe
WO2003028698A2 (en) * 2001-09-26 2003-04-10 Steffens Klaus-Juergen Method and device for producing granulates that comprise at least one pharmaceutical active substance

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2369919A1 (en) * 1976-11-05 1978-06-02 Bayer Ag Extrusion of thermoplastics as microporous foamed profiles - e.g. for irrigation etc., using high extrusion temp. and blowing agent contents
EP0078108A2 (en) * 1981-10-22 1983-05-04 Imperial Chemical Industries Plc Production of PVC irrigation pipe
EP0078108A3 (en) * 1981-10-22 1983-06-01 Imperial Chemical Industries Plc Production of pvc irrigation pipe and the pipe so produced
US4577998A (en) * 1981-10-22 1986-03-25 Imperial Chemical Industries, Plc Production of PVC irrigation pipe and the pipe so produced
WO2003028698A2 (en) * 2001-09-26 2003-04-10 Steffens Klaus-Juergen Method and device for producing granulates that comprise at least one pharmaceutical active substance
WO2003028698A3 (en) * 2001-09-26 2003-10-23 Klaus-Juergen Steffens Method and device for producing granulates that comprise at least one pharmaceutical active substance

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