Classifications

• • 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
  • C08K5/16—Nitrogen-containing compounds
  • C08K5/34—Heterocyclic compounds having nitrogen in the ring
  • C08K5/3467—Heterocyclic compounds having nitrogen in the ring having more than two nitrogen atoms in the ring
  • C08K5/3477—Six-membered rings
  • C08K5/3492—Triazines
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S260/00—Chemistry of carbon compounds
  • Y10S260/24—Flameproof
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S521/00—Synthetic resins or natural rubbers -- part of the class 520 series
  • Y10S521/907—Nonurethane flameproofed cellular product

Definitions

• the invention relates to flame-resistant, thermoplastic molding compositions based on styrene polymers which contain an organic bromine compound as a flame retardant, and to their use for the production of self-extinguishing moldings.
• halogenated Substances can be used as flame retardants for self-extinguishing thermoplastics. To achieve a sufficient effect, relatively large amounts of halogen compounds must be added. However, this adversely affects the mechanical properties of the plastics. It is also known that the flame retardant effect of organic bromine compounds is improved by adding organic peroxides. However, these have the disadvantage that they are toxic and sometimes decompose explosively.
• DT-OS 25 45 223 describes thermoplastic molding compositions based on styrene polymers which contain derivatives of 1,3-thiadiazole as highly effective flame retardants.
• Foamed polystyrene which is flame-retardant with such highly brominated thiazdiazole derivatives, has the disadvantage that a slightly yellow color is caused by the Self-absorption of the flame retardant can occur. It also shows that in some cases the mechanical properties of the foams are adversely affected.
• the object of the invention was therefore to expand the range of highly effective flame retardants and to provide organic bromine compounds which, on account of their property profile, can be used as flame retardants for the various styrene polymers.
• styrene polymers polystyrene and copolymers of styrene occur. Ew with up to 50 w% of comonomers in question.
• Comonomers such as ⁇ -methylstyrene, acrylonitrile such as esters of acrylic or methacrylic acid of alcohols with 1 to 8 carbon atoms.
• impact-modified styrene polymers which are prepared by polymerizing styrene, optionally together with acrylonitrile, in the presence of rubber-like butadiene, isoprene, ethylene / propylene or acrylic ester polymers, for example impact-resistant polystyrene with 2 to 10% by weight polybutadiene .
• Molding compositions which are suitable for producing self-extinguishing foams are of particular importance.
• blowing agents they preferably contain liquid or gaseous organic compounds which do not dissolve the polymer and whose boiling point is below the softening point of the polymer, e.g. allphatic or cycloaliphatic hydrocarbons, such as propane, butane, pentane, hexane, heptane or cyclohexane; furthermore carbon dioxide or halogenated hydrocarbons such as methyl chloride, dichlorodifluoromethane or 1,2,2-trifluoro-1,1,2-trichloroethane.
• Blowing agent mixtures can also be used. It is advantageous to use 3 to 10 percent by weight, based on the molding compositions, of blowing agent.
• the molding compositions contain 0.05 to 5, preferably 0.1 to 3 percent by weight of flame retardant.
• Organic bromine compounds which meet the above-mentioned conditions are suitable as flame retardants.
• other, e.g. aromatically bound bromine atoms may be included.
• This compound can be prepared from acetonitrile either by trimerization and subsequent bromination in glacial acetic acid or by bormation and subsequent trimerization.
• the presence of other known anti-jamming agents and synergists should not be excluded in the molding compounds.
• the molding compositions may also contain other components, e.g. Fillers, color pigments, lubricants, plasticizers, antistatic agents, anti-aging agents, stabilizers or compounds that promote foam formation.
• the organic bromine compounds can, for example, be incorporated into the plastic on a roller, in an extruder or in a kneader. In many cases, they can also be added to the monomers before the polymerization. It is also possible, e.g. in the production of cast films, add the polymers together with the bromine compound to a solution of the plastic and evaporate the solvent.
• the organic bromine compounds are preferably applied superficially to the polymers.
• anti-adhesive agents are particularly suitable for this.
• finely divided silica which is preferably used in amounts of 0.005 to 0.1% by weight, based on the molding composition.
• the polymer containing blowing agent is foamed and welded into molded parts.
• the molding compositions can be in finely divided form, e.g. present as pearls, in the form of granules or as coarse powder, as is obtained when grinding bulk polymers.
• the particles advantageously have a diameter of 0.1 to 6 mm, preferably 0.4 to 3 mm.
• the molding compositions can be processed, for example, by injection molding, extrusion or foaming and sintering in molds to form self-extinguishing moldings or profiles. Because of their relatively low content of organic bromine compounds, the molding compositions according to the invention have softening points which differ only slightly from those of the polymers on which they are based.
• a particular advantage of the bromine compounds used according to the invention is their high effectiveness, even without synergistic additives, such as peroxides or azo derivatives. Furthermore, with comparable bromine content, shorter extinguishing times are achieved than with conventional flame retardants. Drainage is also significantly reduced.
• Example 1 c is repeated using a copolymer of 90% styrene and 10% acrylonitrile. The extinction time was 0 seconds.
• a mixture of 100 parts of a styrene polymer which was prepared by polymerizing 95 parts of styrene in the presence of 5 parts of polybutadiene, and one part of the Flame retardant I is extruded in an extruder with a slot die to films of 1 mm thickness.
• a nozzle for injecting liquids is attached to a twin-screw extruder in the first third of the cylinder.
• a mixture of 100 parts of polystyrene, 1.5 parts of flame retardant I and 1 part of kaolin as a nucleating agent is introduced into this filler neck.
• the temperature in the melting zone is 180 ° C.
• quantities of methyl chloride are injected through the nozzle so that the mixture emerging at the nozzle head contains approximately 10%, based on the polystyrene, of methyl chloride.
• the temperature in the mixing zone is 160 ° C.
• the mixture is cooled to such an extent that the mixture emerging from the nozzle has a temperature of 110 ° C.
• the foam obtained has a density of about 40 g / l. The flame extinguishes practically immediately on a test specimen.
• 0.64 parts of polyvinylpyrrolidone as protective colloid and 0.6 part of sodium pyrophosphate are dissolved in 400 parts of water in a stirred vessel. 200 parts of styrene are added, in which 14 parts of pentane, 0.75 part of benzoyl peroxide and 1 part of the flame retardant I have previously been dissolved. The mixture is heated to 70 ° C. with stirring for 20 hours and held at 85 ° C. for a further 15 hours. The resulting blowing agent-containing polystyrene is separated off, washed and dried. The after exposure Pre-expanded particles obtained from water vapor are welded in a mold to foam polystyrene blocks after further storage with water vapor for one day.
• the color of these blocks is pure white. They are cut from them with the help of an electrically heated wire foam sheets of 1.5 cm thickness. These are stored for several days at room temperature and cut to about 30 x 40 cm. Then one holds such plates with their edge in a luminous gas flame, removes this and measures the time until the foam extinguishes. The extinguishing time is 0 seconds and the samples practically do not ignite.
• An expandable polystyrene granulate with a content of 6.4% pentane and an average particle diameter of 1.5 mm is with 0.3% powdered flame retardant I, and 0.025% silica with an average particle size of 12 / um as an anti-adhesive agent by simply drumming in Paddle mixer mixed for 3 minutes.
• a foam is obtained from the granules by treatment with steam, and an extinction time of 0.5 seconds is measured.
• An expandable polystyrene granulate with a content of 6.4% pentane is mixed with 0.3% by weight of powdered flame retardant X or XI and 0.025% by weight of silica as an anti-wetting agent by simply tumbling in a paddle mixer for 3 minutes.
• a foam is obtained from the granules by treatment with steam.
• hexabromocyclododecane (HBCD) was used as a known flame retardant.

Landscapes

• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
• Compositions Of Macromolecular Compounds (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=6015500

Family Applications (1)

Country Status (6)

Families Citing this family (4)

Citations (3)

Family Cites Families (4)

• 1977
  • 1977-08-03 DE DE19772734926 patent/DE2734926A1/de not_active Withdrawn
• 1978
  • 1978-07-26 DE DE7878100501T patent/DE2861450D1/de not_active Expired
  • 1978-07-26 EP EP78100501A patent/EP0000730B1/fr not_active Expired
  • 1978-07-28 US US05/928,814 patent/US4158086A/en not_active Expired - Lifetime
  • 1978-08-01 IT IT50556/78A patent/IT1109429B/it active
  • 1978-08-02 CA CA308,634A patent/CA1107899A/fr not_active Expired
  • 1978-08-02 JP JP9372778A patent/JPS5428354A/ja active Pending

Patent Citations (3)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events