DE3128875A1 - Halogen-containing compounds, processes for the preparation thereof, and the use of these compounds for flame-proofing thermoplastic synthetic materials - Google Patents

Abstract

The invention relates to halogen-containing compounds, to a process for the preparation thereof, and to the use of these compounds for flame-proofing thermoplastic synthetic materials. The halogen-containing compounds are described by the following general formula I. <IMAGE> where y represents boron, aluminium and antimony, and the radicals and indices have the following significance: Rn: OH, R<1>, R<2> or R<3> <IMAGE> where it applies that: R<4>: lower alkyl group or lower haloalkyl group, X: bromine or chlorine, k l: 0 or integers from 1 to 5 and also k + l max. 5; <IMAGE> where it applies that: R<5>: lower alkyl group or lower haloalkyl group, Z: bromine or chlorine, s, p: 0 or integers from 1 to 4 and also s + p = max. 4 <IMAGE> where Rn, R<5>, Z, s and p have the abovementioned meaning and it also applies that l + p = 1.

Description

halogen-containing compounds, process for preparation

the same and their use for the flame retardant finishing of thermoplastics Plastics The invention relates to halogen-containing compounds which differ from substituted hydroquinones can be derived.

Regarding the state of the art, we mention: (1) US Pat. No. 3,557,053 and (2) US Pat 3 76l 543.

From (1) and (2) are flame retardants based on polymeric phosphoric acid esters of bisphenol A or hydroquinones for the flame retardancy of polycarbonates known. Such flame retardants often do not have the desired effect; in addition, their compatibility with plastics leaves something to be desired when using the known flame retardants with undesirable side reactions the auxiliaries commonly used in thermoplastics, e.g. antioxidants to fear It was therefore the task to propose flame retardants that do not have these disadvantages.

This object is achieved by finding compounds of the general formula 1 where Y stands for boron, aluminum and antimony and the radicals and indices have the following meanings: Rn: OH, Rl, R2 or R3 R1 where: R4: lower alkyl group or lower haloalkyl group X: bromine or chlorine k, 1: 0 or integers from 1 to 5 and furthermore k + 1 max. 5; R2 where: R5: lower alkyl group or lower haloalkyl group Z: bromine or chlorine s, p: 0 or integers from 1 to 4 and furthermore s + p max. 4 R3 where Rn, R5, Z, s and p have the meaning given above and also applies 1 + p ° 1, and for example by a process for the preparation of these compounds from Y (-Hal-) 3, phenols III and hydroquinone derivatives (IV) below the action of bases The invention therefore relates to halogen-containing compounds according to claim 1. The invention also relates to a process for the preparation of compounds according to formula I of claim 1 or mixtures of compounds of general formula I and halogen-containing compounds of formula II.

Phenols of the general formula III are suitable for the preparation of the compounds of the formula 1 according to the invention or mixtures of compounds of the formula I with those of the formula II.

Phenols that are suitable for the implementation are halophenols, such as monobromophenol, monochlorophenol, dibromophenol, dichlorophenol, tribromophenol, Trichlorophenol, pentabromophenol, pentachlorophenol, cresol, monobromo cresol, monochloro cresol, Dibromocresol, dichlorocresol, tribromocresol, trichlorocresol, the haloalkylphenols, such as (2-bromoethyl) dibrophenol, (2-chlororetyl) dichlorophenol, etc. Of those mentioned halogenated phenols are particularly preferred tribromophenol, trichlorophenol, the pentabromophenol and the pentachlorophenol are used.

Mixtures of two or more of the phenols mentioned can also be used used for the preparation of the compound I or mixtures thereof with compound II will.

As disubstituted hydroquinone derivatives of the general formula IV halogenated hydroquinones are particularly suitable. Di-, tri- and tetrahalogenated representatives. Tetrabromohydroquinone is used in particular.

For the preparation of the halogen-containing compounds according to the invention the halogenated phenols of the general formula III are substituted with the Hydroquinones of the general formula IV and with Y- (Hal) 3 in the presence of a base, preferably using a polar organic solvent, at temperatures implemented in the range from 0 to 1000C. As acid scavengers in this implementation Hydroxides of alkali or alkaline earth metals, such as sodium hydroxide, potassium hydroxide, Calcium hydroxide or its carbonates are used. Particularly preferred is one aqueous solution of sodium hydroxide use.

In the compounds of the formula I and II according to the invention, Y is for trivalent metals which enable the formation of halides or oxyhalides are. Y means in particular boron, aluminum and antimony. As halides? - (Hal) 3 The chlorides and bromides of boron and aluminum are mainly used for the implementation and antimony are used.

If SbOCl is used instead of SbCl3> only compounds of the formula For the reaction, preference is given to using polar organic solvents such as halogenated hydrocarbons, in particular ethers, cyclic ethers, ketones, esters or alcohols. It is particularly preferred to use cyclic ethers such as 1,4-dioxane or tetrahydrofuran.

In the implementation of the reactants a, b and c according to patent claim 2, the approach is preferably designed so that the number of hydroxyl equivalents from the phenol of the general formula III and the substituted hydroquinone of the general Formula IV is equal to the number of halogen equivalents of? (Hal) 3. Using of 1 mole of y (Hal) 3, 3 moles of alkali are accordingly required. In a preferredfn Embodiment for the preparation of the halogen-containing compounds according to the invention the reactants Y- (Hal) 3, phenol of the formula III and the hydroquinone derivative of the general formula IV presented in tetrahydrofuran. After that, the required and calculated amount of aqueous sodium hydroxide solution at temperatures in the range between 20 and 50 0C added. A few hours of stirring time using reflux cooling complete the implementation. When working up the reaction mixture, it is essential that the sodium chloride formed is removed. This is easy to do Way by stirring the reaction mixture into an excess of initially charged water or a methanol-water mixture. Then the final halogenated product by 'Filtration isolated and dried. A variant for processing of the reaction product is that, after the reaction, that which is miscible with water Solvent is distilled off and the residue with a chlorinated hydrocarbon is absorbed as a solvent. The resulting suspension is mixed with water washed, the aqueous and the organic phase are separated from each other and the organic phase is evaporated. The halogenated end products fall in the process as relatively low-viscosity, colorless to yellow melts. Another A variant for the preparation of the compounds according to the invention is the use of Mixtures of chlorinated hydrocarbons and water as the reaction medium, wherein an addition of phase transfer catalysts is appropriate. The order of addition the reactant is critical in that it is the chlorine of Y- (Hal) 3 in water, in particular in the alkaline medium, is substituted by OH groups. Measures to push back this less desirable side reaction leading to halogenated products with increased OH number leads, consist in the fact that either the Y- (Hal) 3 only after submission of the the remaining reactants are added or, with the addition of the alkali, only after submission of all other reactants begins.

In addition, the use of higher reaction temperatures, in particular at the beginning of the implementation.

Decisive for the properties of the compounds according to the invention is the molar ratio of Y- (Hal) 3 to substituted used in their preparation Hydroquinone of the general formula IV. The molar ratio of Y- (Hal) 3 a) to benzene derivative c) should be 1 to 20, preferably 2 to 8. When using a low molar ratio from 1 to 2 the reaction products are crosslinked or have a high melting point, with a molar ratio greater than 8 up to 20 the reaction products contain essentially the L. Tris (phenoxy) compound of the general formula II When using molar ratios in the range of greater than The reaction products consist of 2 to 8 based on molecular weight determinations essentially of a mixture of the compound of formula II and a halogen-containing one Compound of the general formula Io The compound 1 according to the invention or mixtures of substances from 1 and II are preferred for the flame retardant finishing of thermoplastics Plastics applied. It has been found that with sufficient halogen - In particular the bromine content of the compounds according to the invention and of the plastic Adequate flame protection in accordance with the regulations of the Underwriter Laboratories for the purpose of classification in one of the fire classes 94 VE-0, 94 f: 1 or 94 VE-2, tested in the vertical fire test. For the flame retardant finish are preferred the usual synergists such as Sb 2 O 3, SnO 2, Fe 2 O 3 and the like known to the person skilled in the art Amounts used together with the fire retardant.

As thermoplastics come for the flame retardant detent into consideration polyethylene, polypropylene, polyisobutylene, polystyrene and the copolymers des styrene with acrylonitrile, also polyamides and polyesters. Particularly preferred impact-resistant thermoplastics such as impact-resistant polystyrene, as well as those with rubbers impact-resistant modified styrene-acrylonitrile copolymers (ABS resins) and from the Polyesters the polybutylene terephthalate. Also polyterblends such as polystyrene / polyphenylene oxide molding compounds can thus be made flame-proof. The flame retardants are used in Amounts from 2 to 25 parts by weight based on 100 parts of the thermoplastic Plastic, applied. The synergists are in quantities of 1 to 10 weight points, based on 100 Ge major parts thermoplastic plastic, in usually effective.

The thermoplastics to be made flame-proof can in addition to the flame retardants and synergists, the usual additives such as stabilizers as well as fillers, color pigments, lubricants, plasticizers, antistatic agents or propellants contained in customary amounts known to the person skilled in the art. The incorporation of the flame retardant, of the synergist as well as any additives that may be used can be used according to suitable and known mixing processes, e.g. in extruders, kneaders or rollers. In particular, concentrates of the flame retardant and the synergist can also be used be made in the desired thermoplastic material.

It has been found that flame retardant mixtures with a content of more than 53% by weight of tris (tribromophenoxy) compound of the general formula II migration problem-; cause me in ABS polymers.

The percentages of tris (tribromophenoxy) compound (formula II) in a mixture of compounds I and II, can be made under certain assumptions Calculate the following equation:% content of (M-2). .100. 1068 Formula II (M-2) . 1068 + 1900 Here, M means the molar ratio (a: c) of Y- (Hal) 3 to the particular used tetrabromohydroquinone as a representative of the general formula IV For molecular weight determinations of the reaction mixture, this equation applies to a good approximation for M b 2, with sodium tribromophenol serving as a further reactant.

In this sense, the claimed quantity ranges are also considered to be approximate to consider When it comes to the flame retardancy of ABS resins, there is one special feature then achieve good mechanics of the molding compound with simultaneous freedom from migration, when the halogen-containing compounds according to the invention of the general formulas I and II are used in a mixture containing 22 to 53% by weight of the compound general formula II, based on the sum of the compounds I and II; the% shares II were calculated using the approximation formula in the last paragraph for M = a / c ç 2.5 to M = a / c 14 calculated for the flame retardant finish with the inventive Compounds an ABS was used, the 24 parts by weight of polybutadiene and one Matrix with a viscosity number of 55 or 80 contained the determination of the viscosity number was carried out analogously to DIN 53 726; 0.5 g of material was added to 100 ml of dimethylformamide solved. The styrene content in the matrix was 65% by weight, the acrylonitrile content at 35% by weight.

The thermoplastic ABS polymers were each 5 parts by weight a synergist (antimony trioxide) and 20 parts by weight of a flame retardant mixed according to the present invention on a twin-screw extruder For testing the mechanical properties of the ABS that the flame retardants according to the invention contains, were on an injection molding machine of the Arberg Allrounder 200 type at 2500C Round disks 2 mm thick produced. The work of damage was carried out in accordance with DIN 53 443, sheet 1 For checking the formation of surface deposits on molded parts made from the molding compositions according to the invention and on those from comparative experiments press plates with the dimensions 100 x 100 x 2 mm were produced at 2300C. the The heating time was 3 minutes and the pressing time at 230 ° C. was 8 minutes. The press plates were stored in a drying cabinet at 600C. After certain periods of time was checked visually whether a surface coating had formed or not.

Polybutylene terephthalate with a relative viscosity trel of 1.67 (measured 0.5% in phenol / o-dichlorobenzene 60:40 at 250C) was taken together with 10 % By weight, based on polymer, of the brominated compounds of a mixture that does not contained more than 70% by weight of tris (tribromophenoxy) compound II, and 6% by weight, based on polymer with antimony trioxide as a flame retardant synergist, in a twin-screw extruder melted. 30% by weight of glass fibers, based on the total mixture, were added to the melt. incorporated. The homogeneous. Mixture was discharged, cooled and granulated. Flat bars 1/8 and 1/16 "thick were injected from the granulate and according to UL 94 checked. The product is classified in fire class V-O according to UL 94. 2 each Test bars were stored for 1, 3 and 7 days at 1700 ° C. in a circulating air drying cabinet. It a slight deepening of color from light ivory to light beige is noted. No deposit was found on the surface. The products show up when checked according to the FTZ pre-standard 547 PV 1 of June 71, no contact damage in the low-voltage range.

The invention is illustrated below by means of examples and comparative experiments explained in more detail. The parts and percentages given in the examples and experiments unless otherwise noted, refer to the weight (cf.

Table 2, in which the results of comparative experiments A to D are included).

Examples 1 - 8 In a glass flask, 0.2 mol AlCl3, x mol- Submitted tetrabromohydroquinone and y mol of tribromophenol in 400 ml of tetrahydrofuran. Then 24.8 g of NaOH are allowed to run in as an approx. 50% solution in water at 5-100C, stirred for 30 minutes at room temperature and then for 6 hours under reflux.

It is filtered off with suction and the filtrate is precipitated in 5 liters of methanol and washed with Water and dry the product at 70 0C under vacuum. 130 bis are obtained 170 g of halogenated u Al-containing compound as a pale solid.

Example 9 In a glass flask, 0.2 mol of AlCl3, 0.04 mol of tetrabromohydroquinone and 0.52 mol of tribromophenol in 400 ml of tetrahydrofuran. Then leave 24.8 g sodium hydroxide solution, as an approx. 50% solution in water, run in at + 100C and stir 18 Hours at room temperature. Tetrahydrofuran is then distilled off and taken the residue is dissolved in 500 ml of 1.2 "dichloroethane. The organic phase is washed 3 times with 100 ml of water each time, the solvent is distilled off. 190 g remain Product melt with a bromine content of 67.5%.

Example 10 Is, as described in Example 9, with SbCl3 instead from AlCl3 worked, the corresponding Sb derivative is obtained.

Examples 11 to 13 and Comparative Experiments A to D make flame resistant of ABS (see Table 2) with mixtures of compounds of the formula I and II.

Table 1 Example molar ratio (x) 1) (y) 1) End product End product AlCl3 mol of tetrabromo mol tribromine% bromine molar weight to tetrabromo hydroquinone phenol hydroquinone 1 2.0 0.1 0.4 71.1 1795 2 2.22 0.09 0.42 71.2 1650 3 2.5 0.08 0.44 70.9 1535 4 3 0.066 0.466 71.0 1400 5 4 0.05 0.50 70.8 1275 6 5 0.04 0.52 70.9 1210 7 7 0.028 0.54 71.0 1145 8 8 0.025 0.55 70.9 1130 1) 2 (x) + (y) = 0.2. 3 2) Mechrolab, Chloroform as a solvent, to conc. = 0 extrapolated Tabel 2 Example flame retardant antimony ABS damage surface fire class from Table 1 trioxide work coating according to [parts by weight] [parts by weight] [parts by weight] [Nm] 800 hours (according to the invention) 10 3 20.0 5 75 12 no VE-O 11 4 20.0 5 75 16 no VE-O 12 5 20.0 5 75 19 no VE-O comparison version (not according to the invention) A 1 20.0 5 75 0.5 no VE-O B 2 20.0 5 75 7 no VE-O C 6 20.0 5 75 20 yes VE-O D 7 20.0 5 75 20 yes VE-O

Claims (7)

Claims Halogen-containing compounds of the following general formula I where Y stands for boron, aluminum and antimony and the radicals and indices have the following meanings: Rn: OH, R¹, R² or R³ R¹: where: R4: lower alkyl group or lower haloalkyl group X: bromine or chlorine k, 1: O or integers from 1 to 5 and furthermore k + 1 max. 5; R²: where: R5: lower alkyl group or lower haloalkyl group Z: bromine or chlorine s, p: 0 or integers from 1 to 4 and furthermore s + p = max. 4 R3 where R, R5, Z, s and p have the meaning given above and 1 + p = 1. 2. Process for the preparation of compounds according to formula I of claim 1 or mixtures of compounds of general formula I and halogen-containing compounds of formula II below by reacting a) halides of Y (Y-Hal3) with b) a phenol of the general formula III and c) a substituted hydroquinone of the general formula IV in the presence of d) at least 3 equivalents of a base, based on t * equivalent Y- (Hal) 3, optionally in the presence of an e) organic solvent which is preferably miscible with water (meaning of the radicals and indices as in claim 1). 3. The method according to claim 2, characterized in that Y- (Hal) 3 a) with so many equivalents of b) + c), based on OH groups, is reacted that to 1 OH equivalent 1 halogen equivalent comes 4. The method according to claim 2, characterized in that that the reactants a) and c) in a range of the molar ratio a / c of 1 until 20 applies. 5. Use of halogen-containing compounds of the general Formula I, optionally mixed with Connections of general Formula II, for the flame retardancy of thermoplastics. 6. Use of halogen-containing compounds of the general Formula I, optionally mixed with s-triazine compounds of the general formula II, for the flame retardancy of thermoplastics, together with a usual synergists for the flame retardant in effective amounts. 7. Use of halogen-containing compounds according to claim 5 or 6 for the flame-retardant finishing of impact-resistant modified with rubber Styrene - acrylonitrile copolymers (ABS resins) with the proviso that as a flame retardant a mixture of the compounds of general formula I and formula II in one Proportion of 22 to 53 parts of compounds of the formula Ii, based on 100 parts I + II, is applied.