DE3412142A1 - Process for the production of flame-retardant products from acrylic polymer - Google Patents

Process for the production of flame-retardant products from acrylic polymer

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Publication number
DE3412142A1
DE3412142A1 DE19843412142 DE3412142A DE3412142A1 DE 3412142 A1 DE3412142 A1 DE 3412142A1 DE 19843412142 DE19843412142 DE 19843412142 DE 3412142 A DE3412142 A DE 3412142A DE 3412142 A1 DE3412142 A1 DE 3412142A1
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Prior art keywords
polymerization
takes place
products
pressure
flame
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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.)
Granted
Application number
DE19843412142
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German (de)
Other versions
DE3412142C2 (en
Inventor
Des Erfinders Auf Nennung Verzicht
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JMC ACRYLGUSS GmbH
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JMC ACRYLGUSS GmbH
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Application filed by JMC ACRYLGUSS GmbH filed Critical JMC ACRYLGUSS GmbH
Priority to DE19843412142 priority Critical patent/DE3412142A1/en
Priority to DE3448013A priority patent/DE3448013A1/en
Publication of DE3412142A1 publication Critical patent/DE3412142A1/en
Application granted granted Critical
Publication of DE3412142C2 publication Critical patent/DE3412142C2/de
Granted legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00—Processes of polymerisation
    • C08F2/44—Polymerisation in the presence of compounding ingredients, e.g. plasticisers, dyestuffs, fillers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F20/00—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride, ester, amide, imide or nitrile thereof
    • C08F20/02—Monocarboxylic acids having less than ten carbon atoms, Derivatives thereof
    • C08F20/10—Esters
    • C08F20/12—Esters of monohydric alcohols or phenols
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K5/00—Use of organic ingredients
    • C08K5/0008—Organic ingredients according to more than one of the "one dot" groups of C08K5/01 - C08K5/59
    • C08K5/0066—Flame-proofing or flame-retarding additives
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2333/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers
    • C08J2333/04—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers esters
    • C08J2333/06—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers esters of esters containing only carbon, hydrogen, and oxygen, the oxygen atom being present only as part of the carboxyl radical
    • C08J2333/10—Homopolymers or copolymers of methacrylic acid esters
    • C08J2333/12—Homopolymers or copolymers of methyl methacrylate

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  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
  • Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
  • Polymerisation Methods In General (AREA)

Abstract

The invention relates to a process for the production of flame-retardant products from acrylic polymer to whose monomers are added, inter alia, a flameproofing agent and, in order to produce foamed products, additionally blowing agents and crosslinking agents. The polymerisation, which takes place at elevated temperature, is carried out according to the invention for a short time and under superatmospheric pressure. The process is suitable both for foamed and for unfoamed products. The preferred pressure during the polymerisation is in the range from 8 to 25 bar. <IMAGE>

Description

Verfahren zur Herstellung von schwer entflammbaren Process for the production of flame retardant

Erzeugnissen aus Acrylpolymerisat. Acrylic polymer products.

Die Erfindung betrifft ein Verfahren zur Herstellung von schwer entflammbaren Erzeugnissen aus Acrylpolymerisat, wie Polymethylmetacrylat und dergleichen.The invention relates to a method for producing flame retardant Acrylic polymer products such as polymethyl methacrylate and the like.

Die Herstellung von Erzeugnissen aus Polymeren auf Acrylatbasis, nachfolgend in kompakter Form mit dem landläufigen Ausdruck "Acrylglas" und in geschäumter Ausführung als "Acrylschaum" bezeichnet, wird hier als bekannt unterstellt. Die Monomere werden mit bestimmten Zusätzen unter Energiezufuhr polymerisiert, wodurch sich die Momomermoleküle zu Makromolekülen verketten. Acrylglas ist ein hartes schlagfestes durchsichtiges glasklares Erzeugnis. Der Acrylschaum entsteht durch einen Zusatz von Treibmittel und einem die Stabilisierung des Schaums bewirkenden Vernetzer zum Monomer.The manufacture of products from acrylate-based polymers, below in compact form with the popular expression "acrylic glass" and in a foamed version referred to as "acrylic foam" is assumed to be known here. The monomers will polymerized with certain additives under the supply of energy, whereby the momomer molecules chain to form macromolecules. Acrylic glass is a tough, impact-resistant clear one crystal clear product. The acrylic foam is created by adding a propellant and a crosslinker to the monomer which stabilizes the foam.

In herkömmlicher Weise hergestelltes Acrylglas und Acrylschaum erfüllen auch bei Zusatz handelsüblicher Flammschutzmittel nicht die Anforderungen nach DIN 4102-B1.Conventionally produced acrylic glass and acrylic foam meet Even with the addition of commercially available flame retardants, the requirements according to DIN are not met 4102-B1.

Der Tropfpunkt des Materials liegt über dem Flammpunkt.The dropping point of the material is above the flash point.

Dadurch verbrennt das Material, ehe es abtropft. Aufgabe der vorliegenden Erfindung ist nun die Schaffung eines Verfahrens zur Herstellung von schwer entflammbaren Erzeugnissen aus Acrylglas und Acrylschaum, welche die Anforderungen nach DIN 4102-B1 erfüllen. Insbesondere soll der Flammpunkt bei gleichzeitiger Absenkung des Tropfpunktes so weit angehoben werden, daß er über dem Tropfpunkt liegt, damit das Material unter der Einwirkung einer Flamme abtropft, ehe es zu brennen beginnt.This burns the material before it drips off. task The present invention is now to provide a method of manufacture of flame-retardant products made of acrylic glass and acrylic foam, which the Meet the requirements of DIN 4102-B1. In particular, the flash point should be at the same time Lowering the dropping point raised so far that it is above the dropping point so that the material drips off under the action of a flame before it closes starts to burn.

Zur Lösung dieser Aufgabe wird erfindungsgemäß vorgeschlagen, die Polymerisation kurzzeitig und unter Überdruck vorzunehmen.To solve this problem it is proposed according to the invention that Polymerization to be carried out briefly and under excess pressure.

Nach dem erfindungsgemäßen Verfahren hergestellte Erzeugnisse aus Acrylglas und Acrylschaum erfüllen überraschenderweise die Anforderungen nach DIN 4102-B1. Die kurze radikale Polymerisationszeit ist nur aufgrund des im Autoklaven aufgebauten Überdrucks möglich. Durch den Einbau der Flammschutzmittel wird der Flammpunkt angehoben.Products made by the method according to the invention Acrylic glass and acrylic foam surprisingly meet the requirements of DIN 4102-B1. The short radical polymerization time is only due to the fact that it is in the autoclave built-up overpressure possible. By installing the flame retardants, the Flash point raised.

Gleichzeitig wird der Fließpunkt des Materials durch die bei der radikalen Polymerisation entstehenden kurzen Ketten auf Temperaturen um ca. 1500C abgesenkt. Dadurch wird erreicht, daß das im Brandschacht nach DIN 4102-B1 geprüfte Material brennend abtropft, bevor das Material, das sich oberhalb des abtropfenden Materials befindet, durch die eigene Flamme seinerseits entflammt werden kann. Sobald das so eingestellte Material nicht mehr im Einflußbereich einer fremden Flamme liegt, erlischt es von selbst.At the same time, the flow point of the material is determined by the radical Polymerization resulting short chains lowered to temperatures around 1500C. This ensures that the material tested in the fire shaft according to DIN 4102-B1 burning drips before the material that is above the dripping material can be ignited by its own flame. As soon as that material adjusted in this way is no longer in the area of influence of an external flame, it goes out by itself.

Von Bedeutung ist, daß man bei der Erzeugung von Acrylglas keine Vernetzer einbaut, denn diese würden den durch die kurzen Ketten reduzierten Tropfpunkt wieder nach oben anheben.It is important that no crosslinkers are used in the production of acrylic glass built in, because these would restore the dropping point reduced by the short chains lift upwards.

Die Menge an zugesetztem Flammschutzmittel soll 13 bis 22 Gew.-%, vorzugsweise 15 bis 17 Gew.-%, betragen.The amount of flame retardant added should be 13 to 22% by weight, preferably 15 to 17% by weight.

Die Ergebnisse wurden erzielt mit handelsüblichem Flammschutzmittel, die unter der Bezeichnung FYROL FR-2 bzw. FYROL CEF bzw. FYROL DMMP im Handel sind Gleiche Ergebnisse dürften jedoch auch mit anderen handelsüblichen Flammschutzmitteln erreichbar sein.The results were achieved with commercially available flame retardants, which are sold under the name FYROL FR-2 or FYROL CEF or FYROL DMMP However, the same results should also be obtained with other commercially available flame retardants be available.

Der Überdruck liegt bevorzugt im Bereich von 8 bis 25 bar.The overpressure is preferably in the range from 8 to 25 bar.

Innerhalb dieses Druckbereiches werden die höheren Drücke von 15 bis 25 bar für Acrylschaum vorgesehen, weil hier noch die Wirkung des Treibmittels kompensiert werden muß.Within this pressure range, the higher pressures from 15 to 25 bar intended for acrylic foam, because here the effect of the propellant compensates must become.

Bei der Erzeugung von Acrylglas kann im unteren Druckbereich von dem Mittel etwa 10 bar die Polymerisation durchgeführt werden.When producing acrylic glass, in the lower pressure area of the Average about 10 bar the polymerization can be carried out.

Die Polymerisationsdauer liegt in der Regel zwischen 2 und 10, insbesondere 7 bis 8 Stunden.The polymerization time is usually between 2 and 10, in particular 7 to 8 hours.

Während der gesamten Polymerisationsdauer wird der Überdruck aufrechterhalten. Die Zufuhr von Wärme beginnt, nachdem der Druck im Autoklaven aufgebaut ist. Die Temperaturerhöhung kann stufenweise erfolgen derart, daß das in Formen befindliche Material zunächst auf 40 bis 60"C erwärmt und dort einige Zeit gehalten wird. Für ein bis drei Stunden wird dann die Temperatur auf über 80"C angehoben. Sie liegt bei Acrylglas in der Spitze bei 140"C und bei Acrylschaum bei 100"C. Anschließend erfolgt noch unter Überdruck die Temperaturabsenkung auf 60"C für Acrylglas und 20"C für Acrylschaum, jeweils während etwa zwei Stunden. Unmittelbar vor der Entnahme der Formen aus dem Autoklaven wird der Druck auf Atmosphärendruck abgesenkt. Danach können die Acryl-Erzeugnisse entformt werden.The overpressure is maintained during the entire duration of the polymerization. The supply of heat begins after the pressure in the autoclave has built up. the The temperature can be increased in stages so that the mold located Material is first heated to 40 to 60 "C and held there for some time. For The temperature is then raised to over 80 "C for one to three hours. It is then with acrylic glass in the tip at 140 "C and with acrylic foam at 100" C. Afterward the temperature is lowered to 60 "C for acrylic glass and under overpressure 20 "C for acrylic foam, for about two hours each time. Immediately before removal of the molds from the autoclave, the pressure is reduced to atmospheric pressure. Thereafter the acrylic products can be demolded.

In Fig. 1 ist ein Polymerisationszyklus für Acrylschaum und in Fig. 2 für Acrylglas aufgezeichnet. Diese Polymerisationszyklen sind nur beispielhaft und nicht beschränkend zu verstehen. Abweichungen in Temperatur, Zeit und Ablauf sind möglich.In Fig. 1 is a polymerization cycle for acrylic foam and in Fig. 2 recorded for acrylic glass. These polymerization cycles are only exemplary and not to be understood in a limiting sense. Deviations in temperature, time and sequence are possible.

Claims (9)

Patentansprüche 1. Verfahren zur Herstellung von schwer entflammbaren Erzeugnissen aus Acrylpolymerisat, deren Monomeren u.a. ein Flammschutzmittel und zur Erzeugung geschäumter Produkte zusätzlich Treibmittel und Vernetzer zugesetzt werden, wobei die Polymerisation bei erhöhter Temperatur erfolgt, d a d u r c h g e k e n n z e i c h n e t , daß die Polymerisation kurzzeitig und unter Überdruck vorgenommen wird. Claims 1. Process for the production of flame retardant Acrylic polymer products, their monomers, among other things, a flame retardant and For the production of foamed products, blowing agents and crosslinkers are also added be, the polymerization taking place at elevated temperature, d u r c h it is not noted that the polymerisation takes place briefly and under excess pressure is made. 2. Verfahren nach Anspruch 1, d a d u r c h g e -k e n n z e i c h n e t , daß die Polymerisation unter einem Druck im Bereich von 8 bis 25 bar bei Temperaturen im Bereich von 60 bis 140"C erfolgt.2. The method according to claim 1, d a d u r c h g e -k e n n z e i c h n e t that the polymerization takes place under a pressure in the range from 8 to 25 bar Temperatures in the range from 60 to 140 "C takes place. 3. Verfahren nach Anspruch 2, d a d u r c h g e -k e n n z e i c h n e t , daß die Polymerisation zur Erzeugung nicht-geschäumter Produkte bei einem Druck von 8 bis 15 bar erfolgt.3. The method according to claim 2, d a d u r c h g e -k e n n z e i c h n e t that the polymerization to produce non-foamed products at a Pressure of 8 to 15 bar takes place. 4. Verfahren nach Anspruch 3, d a d u r c h g e -k e n n z e i c h n e t , daß die Polymerisation bei einem Druck von 10 bar erfolgt.4. The method of claim 3, d a d u r c h g e -k e n n z e i c h n e t that the polymerization takes place at a pressure of 10 bar. 5. Verfahren nach Anspruch 2, d a d u r c h g e -k e n n z e i c h n e t , daß die Polymerisation zur Erzeugung geschäumter Produkte bei einem Druck im Bereich von 10 bis 20 bar erfolgt.5. The method according to claim 2, d a d u r c h g e -k e n n z e i c h n e t that polymerization to produce foamed products at one pressure takes place in the range of 10 to 20 bar. 6. Verfahren nach einem der Ansprüche 1 bis 5, d a -d u r c h g e k e n n z e i c h n e t , daß dem Monomer 13 bis 22 Gew.-% Flammschutzmittel zugesetzt wird.6. The method according to any one of claims 1 to 5, d a -d u r c h g e It is not noted that 13 to 22% by weight of flame retardants were added to the monomer will. 7. Verfahren nach Anspruch 6, d a d u r c h g e -k e n n z e i c h n e t , daß dem Monomer 15 bis 17 Gew.-% Flammschutzmittel zugesetzt wird.7. The method according to claim 6, d a d u r c h g e -k e n n z e i c h n e t that 15 to 17 wt .-% flame retardant is added to the monomer. 8. Verfahren nach einem der Ansprüche 1 bis 7, d a -d u r c h g e k e n n z e i c h n e t , daß die Polymerisation während 6 bis maximal 10 Stunden vorgenommen wird.8. The method according to any one of claims 1 to 7, d a -d u r c h g e it is not stated that the polymerization lasts for 6 to a maximum of 10 hours is made. 9. Verfahren nach einem der Ansprüche 1 bis 8, d a -d u r c h g e k e n n z e i c h n e t , daß bei der Polymerisation während zwei Stunden eine Temperatur über 80"C eingestellt wird, insbesondere 100"C für Acrylschaum und 140"C für Acrylglas.9. The method according to any one of claims 1 to 8, d a -d u r c h g e it is not noted that a temperature for two hours during the polymerization is set above 80 "C, in particular 100" C for acrylic foam and 140 "C for acrylic glass.
DE19843412142 1984-03-31 1984-03-31 Process for the production of flame-retardant products from acrylic polymer Granted DE3412142A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
DE19843412142 DE3412142A1 (en) 1984-03-31 1984-03-31 Process for the production of flame-retardant products from acrylic polymer
DE3448013A DE3448013A1 (en) 1984-03-31 1984-03-31 Process for the production of foamed, non-flammable products from polyacrylates

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19843412142 DE3412142A1 (en) 1984-03-31 1984-03-31 Process for the production of flame-retardant products from acrylic polymer

Publications (2)

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DE3412142A1 true DE3412142A1 (en) 1985-10-10
DE3412142C2 DE3412142C2 (en) 1989-01-26

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DE19843412142 Granted DE3412142A1 (en) 1984-03-31 1984-03-31 Process for the production of flame-retardant products from acrylic polymer

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1989004342A1 (en) * 1987-11-13 1989-05-18 Fraunhofer-Gesellschaft Zur Förderung Der Angewand Process for producing hard acrylic and/or methacrylic polymer foams without using fluorocarbons as foaming agents

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1240088A (en) * 1959-07-24 1960-09-02 Process for polymerization and die-casting of plastic resins, especially acrylic resins
DE2134327A1 (en) * 1970-01-02 1973-01-18 Stauffer Chemical Co FLAME RETARDANT POLYMETHYL METHACRYLATE COMPOSITIONS
DE2520635A1 (en) 1975-05-09 1976-11-18 Basf Ag FINE PARTITION, EXPANDABLE STYRENE POLYMERIZED WITH GOOD PROCESSABILITY

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1240088A (en) * 1959-07-24 1960-09-02 Process for polymerization and die-casting of plastic resins, especially acrylic resins
DE2134327A1 (en) * 1970-01-02 1973-01-18 Stauffer Chemical Co FLAME RETARDANT POLYMETHYL METHACRYLATE COMPOSITIONS
DE2520635A1 (en) 1975-05-09 1976-11-18 Basf Ag FINE PARTITION, EXPANDABLE STYRENE POLYMERIZED WITH GOOD PROCESSABILITY

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1989004342A1 (en) * 1987-11-13 1989-05-18 Fraunhofer-Gesellschaft Zur Förderung Der Angewand Process for producing hard acrylic and/or methacrylic polymer foams without using fluorocarbons as foaming agents

Also Published As

Publication number Publication date
DE3412142C2 (en) 1989-01-26

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