DE2543746A1 - Flame retardant bromine contg. acrylate and methacrylate (co)polymers - based on bromo benzyl (meth)acrylates or bromo xylylene bis (meth)acrylates - Google Patents

Abstract

(Co)polymers are claimed which contain units of (meth)acrylates of formula (I) (where n = 0 or 1, X = (pref.) Br or (opt. (Cl and R = H or CH3. (Co)polymers of monomers (I) are useful flame retardant agents and polymers, esp. for incorporation into polymersters suchas polybutylene terepthalate, ABS, polycarbonates polyacetals and polyurethanes. Pref. (I) is a tetra(bromo, chloro)xylylenebis(meth) acrylate with 3-4 Br atoms and 0-1 Cl atmos, in which the methyleneacrylate gps. are o- m- or p- with respect to each other.

Description

Polymers and copolymers based on tetrabromo

xylylene diacrylate and substituted acrylates The main application P 25 27 802.8 describes, inter alia, polymers and copolymers based on of tetrabromo-xylylene-bisacrylate and bis-methacrylate and a process for their Production, now that the corresponding ortho- and met-a-isomeric bisacrylates and bismethacrylates according to the simultaneous patent application P ............ = OZ: 75 095 (2510) are accessible, is now the production of the polymers and copolymers based on these unsaturated ones characterized by structural formulas (1) and (2) Esters possible.

The present patent application relates to polymers and copolymers based on tetrabromo xylylene diesters of the formulas (1) and (2) where R = H or a methyl group Another subject matter is a process for the preparation of these polymers and copolymers by methods of free-radical polymerization of ethylenically unsaturated compounds, which is characterized in that monomers of the formulas (1) and / or (2), optionally with further ethylenically unsaturated monomers are polymerized.

The core substituent X denotes the possibility that in addition to four Bromine substituents, or 0 to 1 chlorine and then correspondingly 3 to 4 bromine as core substituents can occur.

The comonomers mentioned for the preparation of the copolymers are those mentioned Acrylates and methacrylates free-radically copolymerizable, ethylenically unsaturated Monomers, in particular styrene, acrylonitrile, acrylic acid esters and methacrylic acid esters with preferably 1 to 6 carbon atoms in the alcohol radical, unsubstituted Xylylene acrylates and methacrylates and their chlorine substitution products according to P 24 30 629.4, butadiene and isoprene, fumaric and maleic acid or their anhydride, their esters, if appropriate vinyl chloride, vinylidene chloride and others are also suitable.

The polymerization of several comonomers to terpolymers is here also provided, such as the crosslinking of UP resins, which are made of a Diol component such as ethylene glycol or neopentyl glycol, an unsaturated acid component such as boumaric or maleic acid, optionally an additional dicarboxylic acid, and subsequent copolymerization of the unsaturated reactive solvent e.g. Styrene and the unsaturated resin base with substances of the formulas (1) or (2) will.

Preferred are styrene, methyl methacrylate, among others.

As a result of the multifunctionality of the unsaturated esters of the structural formulas (1) and (2) are always crosslinked, insoluble homopolymers or else Copolymers obtained.

The polymerization mechanism for both the homo- and the Copolymerization is radical. Organic or inorganic radical formers can be used Peroxides or aliphatic azo compounds can be used. Used with preference are dibenzoyl peroxide, dicumyl peroxide or potassium peroxydisulfate and azodiisobutyronitrile. The radical formers can be thermal, high-energy radiation or be stimulated to decay by a redox reaction. The usual polymerization temperatures generally in the range from 0 ° O to 15,000 are suitable.

The polymerization or copolymerization can take place in bulk, in solutions or in suspension.

If the homopolymerization is carried out in solution, it has the character of a precipitation polymerisation, since the crosslinked by polymerisation Polybisacrylates or polybismethacrylates of structural formulas (1) and (2) in solvents are insoluble.

Are to be crosslinked xetrabromoxylylene bis polyacrylate by polymerisation or-bis-polymethacrylates are produced, so it is not necessary to synthesize them the monomers of the structure formulas (1) or (2) from acrylic or methacrylic acid and Detrabromo xylylene dichloride from the subsequent crosslinking radical polymerization to be separated in terms of equipment or time; and: the condensation reaction for ester formation as well as the polymer sation can be carried out in a “one-pot reaction” without isolation or. Einigung the intermediate of structural formulas (1) or (2) carried out will. The crosslinked polymer, which is insoluble, is filtered off with suction, with organic solvent washed with water, washed free of chloride and dried.

In the crosslinking copolymerization, depending on the nature of the Comonomers and the solvent either low-solvent powdery products or solvent-containing swollen polymer gels are obtained.

One advantage of the copolymers is their flame retardancy or incombustibility.

It is common practice to make plastics difficult to ignite or to make them incombustible during their manufacture or processing Flame-retardant substances added.

As a rule, substances are used for this purpose that are compatible with the organic The polymers that make up plastics have no chemical relationship whatsoever such as halogen or also organic or inorganic containing phosphorus and nitrogen low molecular weight substances or mixtures of such compounds with metal oxides, which sometimes reinforce each other in their flame-retardant effect. Such In addition to their flame-retardant effect, additives to plastics always have side effects, which are usually undesirable because they have the characteristic properties change the plastics disadvantageously and limit their applicability. Act like that inevitably all of the flame retardant substances added to the plastic in powder form and are retained as a powder or excreted as a separate phase not only in the desired flame-retardant manner, but also in addition as fillers that change the mechanical properties, usually embrittling act and worsen the elongation at break and impact strength.

In almost all cases, the added flame retardants tend to be more or less likely to diffuse out of the plastic again; Because of this Not only is the incombustibility of plastics gradually chalked out again repealed but for many purposes those are flame-resistant Plastics cannot be used, for example for the construction of electrical units.

The advantage of the method according to the invention of the flame retardant finish lies in the fact that the flame retardant is made by copolymerization (and thereby homopolar Bond) is connected to the plastics, which makes it impossible to husk it.

Furthermore, since the anti-inflammatory agent has no filler character has no deterioration in mechanical properties; it will be in In contrast to this, improvements, in particular of the thermomechanical values, were achieved.

The crosslinked polymers or copolymers of the bromine-containing bisacrylic or bismethacrylic esters of structures (1) and (2) have one for brominated organic Compounds have unusual thermal stability, which makes processing problem-free or a use of the polymers and copolymers according to the invention at temperatures Permitted up to 3000C or 20000 without risk of decomposition or thermal damage.

The bisacrylates and bis-methacrylates of structures (1) or (2) represent also represent interesting components for thermosetting (radically crosslinkable) resins.

It is possible here to cure the bisester in substance after shaping or other acrylates or bisacrylates as reactive crosslinking components to mix in.

Casting resins made from tetrachloroxylylene bisacrylate are of particular interest or bis-methacrylate, styrene and tetrabromoxylylene bisacrylate or bis-methacrylate as flame retardant components.

These are casting resins, which in the hardened state in their mechanical and thermomechanical properties those of heat resistant UP resins. Through the cross-linking copolymerization of the brc-ated unsaturated esters of structures (1) or (2) with the other resin components the flame retardant is optimally distributed and through homeopolar bonding in the cast resin anchored, which guarantees an optimal flame retardant effect and prevents chalking.

As "comonomers" for tetrabromo xylylene diesters of structures (1) or (2) The styrenic solutions of bi-resins can also be used with preference.

Unsaturated polyester resins (UP resins) based on unsaturated substances and optionally saturated dicarboxylic acids such as maleic acid or maleic anhydride and fumaric acid, phthalic anhydride, iso- and terephthalic acid as well as divalent ones Alcohols such as ethylene glycol and neopentyl glycol can be used in an active monomer how styrene is dissolved into casting resins.

The maleate or fumarate double bonds react during hardening of the UP resin with the double bonds of styrene under crosslinking radicals Copolymerization. If the detrabromo xylylene diesters of structures (1) or (2) They are added as a third component to the solutions of UP resins in styrene included in the curing process during curing, resulting in valuable property improvements the castings lead.

For example, the heat resistance increases according to Martens a UP resin based on 0.5 mol of neopentyl glycol, 0.5 mol of ethylene glycol, 0.4 mol of phthalic anhydride and 0.6 mol of fumaric acid, 50-60 parts by weight in 50 - 40 wt. Parts of styrene dissolved and cured by adding 15% by weight of the tetrabromo-m-xylylene bisacrylate to the styrenic solution by approx. 100 and by adding in amounts of 20% by weight by about 150 ° C., surprisingly the impact and core impact strength are retained. With the heat resistance The bisacrylate also increases the flexural strength.

Through the cross-linking copolymerization with 15 wt .-% or 20 wt .-% Getrabromxylylene bisacrylate will add 8.5 or 11.3% bromine to the cured UP resin introduced so that by adding 5 or 7 wt. Sb2O3 self-extinguishing castings can be obtained with the characterization according to U1-2est 94 / VO.

Homopolymers and copolymers with a high proportion of substances of the formulas (1) or (2) in the range from 40 to 99.9, preferably 70-99.9% by weight as polymeric flame retardants use, whereby due to the insolubility the gradual removal of the flame retardants by solvents is very advantageous and their vapors from the flame-retardant molded bodies are prevented, and so on the described high melting points or the infusibility and the high decomposition temperatures an unusually long-lasting flame resistance of the flame-protected moldings as well at high ambient temperatures.

There is also the slight tendency given by polar parts of the molecule for emigration or chalking further reduced, apparently as a result the regular angulation of the polymer chains because of -the o- or m-position of the linking Acrylate or methacrylate substituents.

Example 1 (crosslinking polymerization of tetrabromo-m-x'ylebisacrylate ) In a reaction vessel equipped with a paddle stirrer, gas inlet tube and Reflux condenser, 200 g of tetrabromo-mxylylene diacrylate with a melting point of 1050-1080C dissolved in 800 ml of methyl glycol with warming. There will be a pass-through weak nitrogen stream 2 g, corresponding to 1% by weight, based on the monomer, Dicumyl peroxide added as a polymerization initiator and set to the polymerization temperature 125 ° C heated. The addition begins as a result of the precipitated crosslinked polymer and after only 1 hour a pulpy polymer suspension has formed. It is polymerized for a total of 6 h at 125 ° C., then suctioned off with methanol Washed out with water and dried up to 1500C.

189 g of a cross-linked, insoluble and immeasurable, powdery, colorless polymer obtained with a bromine content of 54.8, Chlorine 0.9.

No acrylic ester double bonds can be detected by IR analysis.

The crosslinked product is shown on the thermobalance (air; heating rate 80C / min) the following weight losses: 160 at 302 ° C; 5% at 3180C; 10% at 326 ° C.

The crosslinked bisacrylate shows the following sieve analysis: > 500 µ 2.8% by weight 200 - 500 µ 6.9 "150 - 200 µ 16.0" 100 - 150 µ 49.2 "7G - 100 u 21.5 <70 F1 4.6 "Example 2 (Crosslinking polymerization of tetrabromo-m-xylylene bismethacrylate ) According to the procedure of Example 1, 200 g of lotrabromm-xtylylene bismethacrylate with a melting point of 970-99 ° O in 600 ml of methyl glycol using 1.4 g dicumyl peroxide polymerized in a crosslinking manner.

193 g of an insoluble, immeasurable colorless polymer powder are obtained obtained with a bromine content of 53.8%.

The weight loss during thermal storage in an air atmosphere at 2000C is 2.4% in 24 h and 2.9% in 48 h.

Example 3 (crosslinking polymerization of tetrabromo-o-xylylene bisacrylate ) In a reaction vessel equipped with a paddle stirrer, reflux condenser and gas inlet tube 100 g of tetrabromo-o-xylylene bisacrylate with a melting point of 100 are added under heating - 1020C dissolved in 400 ml of methylglycol and while passing through a weak stream of nitrogen 3 g of dibenzoyl peroxide paste (50%), corresponding to 1.5% by weight of dibenzoyl peroxide, as Initiator added and to the polymerization temperature of 800C set. It is polymexized for 3 h at 80 ° C., 3 h at 90 ° C. and 2 h at 110 ° C.

The resulting polymer suspension is filtered off with suction with methanol washed and dried to constant weight at 4500C.

96 g of a cross-linked, insoluble and infusible, colorless, powdery polymer obtained with a bromine content of 56.1.

Acrylic ester double bonds can no longer be detected by IR analysis.

The weight loss during thermal storage in an air atmosphere at 2000C is 2.9% in 24 h and 3.2% in 48 h.

Example 4 (Preparation of crosslinked tetrabromo-m-xylylene bisacrylate from tetrabromo-m-xylylene dichloride and acryffic acid) For the solution of 165.6 g (2.3 Mol) acrylic acid and 0.3 g of hydroquinone in 1.8 1 of methyl glycol are stirred with stirring 84 g (2.1 mol) of sodium hydroxide, dissolved in 84 ml of water, were added. It will be 492 g (1 mol) of tetrabromo-m-xylylene dichloride are added and the reaction temperature is raised 110 ° C heated. After a reaction time of 1.5 hours, 8 g of dicumyl peroxide are added and polymerized at 12500 for 6 hours while passing through a gentle stream of nitrogen.

After isolating, washing out (methylglycol, then water) and drying (up to 1500C), 537 g of crosslinked, insoluble and infusible are obtained Obtained polymer. The yield is approx. 96% of the theory. based on the used etrabromoxylylene dichloride.

The bromine content is 53.0%, the chlorine content 1.6%. The chlorine content results from a low bromine-chlorine exchange = n core in the production of the Tetrabromo-m-xylylene dichlorias from the tetrabromoxylene. Weight loss on the Thermal balance (air; heating rate 8 ° C / min) is 1% at 304 ° C, 5% at 312 ° C and 10 % at 322 ° C.

Example 5 (Preparation of cross-linked tetrabromo-xylylene bisacrylate from tetrabromo-o-xylylene dichloride and acrylic acid) Following the procedure of Example 4, but using anhydrous soda as the salt former, are made from the Reaction components 61.8 g acrylic acid, 0.11 g hydroquinone, 45.7 g Na2OC3, 184.5 g of tetrabromo-o-xylylene dichloride and 3.75 g of dioumyl peroxide in 675 ml of methyl glycol 195 g of crosslinked polymer obtained, which is approx. 93% yield, based on the tetrabromoxylylene dichloride, is equivalent to.

The weight loss on the thermobalance (air; heating rate 8 ° C / min ) is 1% at 2970C; 5 ffi at 32000 and 10% at 333 ° C.

Acrylic ester double bonds are no longer detectable in the IR spectrum.

Example 6 (tetrabromo-m-xylylene bisacrylate as a reaction component a bisacrylate resin) A mixture of 100 g of p-xylylene bisacrylate (bp. 720 - 750G), 50 g of tetrachloro-m-xylylene bismethacrylate (melting point 83 ° C and 25% Tetrabromous xylylene bisacrylate (melting point 1050-10800) is melted with 1% by weight of dioumyl peroxide added as a curing catalyst and poured into molds. At 1150C it is 3 hours hardened and post-hardened for 4 hours at 1350C. It becomes transparent, almost colorless 4 mm or 2 mm thick plates produced with a chlorine content of 9.7% and a Bromine content of 8.

The 4 mm board has an impact strength of 5.7 KJ / m2 and a Heat resistance of 920C (Martens) or 107 ° C (ISO / R 75; A).

The 2mm plate proves to be self-extinguishing after UL test.

Oharskterization: cung: 94 / VO.

For comparison, one shows a cast resin mixture consisting of 125 g of p-xylene bisacrylate and 50 g of tetrachloro-m-xylylene bis-methacrylate according to the same Procedure produced 4 mm plate an impact strength of 5.2 EJ / m2 and a Heat resistance of 8700 (Martens), or 96 ° C (ISO / R 75; A).

A 2 mm thick casting gave the value “failed” in the UL / 94 test.

Example 7 (tetrabromo-m-xylylene bisacrylate as a reaction component a bisacrylate resin composition) A resin mixture consisting of 150 g of tetrachlo-m-xylylenbis acrylate (mp 65-670C) and 25 g tetrarbom-m-xylylene bisacrylate (mp 105-1070C) is melted together, mixed with 1% by weight of dibenzoyl peroxide Psste (50 ig) and in a form 3 hours at 850C and then 1 4 hours at 1300C cured to a 4 mm thick plate with the following property profile.

Flexural strength 123 N / mm2 ball indentation hardness, 30 sec. 118 N / mm2 impact strength 6.7 EJ / m2 notched impact strength 1.9 KJ / m2 heat resistance 1020C according to Martens according to ISO / R 75; A 111 ° C. Example 8 (tetrabromo-o-xylylene bisacrylate as a reaction component a styrenic bisacrylate resin solution) 300 g of tetrachloro-p-xylylene bisacrylate (mp. 116-117 ° C) and 100 b of tetrabromo-o-xylylene bisacrylate (melting point 1000-1020C) are in 400 g of styrene dissolved. After adding 2% by weight dibenzoxyl peroxide paste (50%) the resin solution is poured into molds and 4 hours at 80 - 850C and then Cured for 4 h at 135 ° C.

A 4 mm plate has a flexural strength of 112 N / mm2, one Impact strength of 9.3 KJ / m² and a heat resistance of 1150C (Martens) or 12900 (ISO / R 75; A).

A 2 mm plate proves to be self-extinguishing in the UL-2est, characterization: 94 / VO.

Examples 9-11 (tetrabromo-m-xylylene bisacrylate as crosslinking component in unsaturated polyester resin solutions) A UP resin was produced on the Based on 0.5 mol of ethylene glycol, 0.5 mol of neopentyl glycol, 0.4 mol of phthalic anhydride and 0.6 moles of fumaric acid. The resin with a molecular weight determined by gel chromatography MGPC = 2800 is dissolved in 50 parts by weight in 50 parts by weight of styrene and this is styrenic UP resin solution based on tetrabromo-m-xylylene bisacrylate in amounts of 5 to 20% by weight on the total amount added (example 10 or 11).

After curing (cold curing with 2% dibenzoyl peroxide paste ( 50%) and 0.2 mol ffi dimethylaniline solution (10% in styrene) at 5000 and post-curing at 135 ° C. for 4 h, there are 4 mm transparent sheets with the following properties obtain. For comparison, the values of the cured styrenic UP resin solution are without bisacrylate addition listed (Example 9).

UP resin solution UP resin solution / bisacrylate without additives 85/15 80/20 Example 9 10 11 Flexural strength N / mm2 93.5 107.0 116.5 ball indentation hardness, 2 30 sec. N / mm² 1480 1475 1510 Impact strength KJ / m² 5.8 7.2 6.4 Heat resistance according to Martens ° C 95 106 112 according to ISO / R 75; A ° C 114 124 127 By the addition 15% by weight of the tetrabromo xylylene bisacrylate increases the heat resistance of the cured UP resin by approx. 1000 and by adding 20% by weight by approx.

15 ° C without reducing the impact strength. Also an improvement the flexural strength can be observed.

Are in the UP resin solutions mixed with tetrabromo-m-xylylene bisacrylate (according to Example 10 or 11) before curing, 5% or 7% by weight of anthomonic trioxide stirred in, self-extinguishing castings are obtained in the UL test; Characterization: 94 / VO.

Claims (4)

P atent claims 1. Polymers and copolymers based on tetrabiomxylylene diesters of structural formulas (1) and (2) where R = H or a methyl group, containing basic building blocks of the structural unit the nucleus being substituted by the two organic substituents in the meta or ortho position. 2. Process for the preparation of polymers and copolymers according to claim 1 according to procedures of the radical isher Polymerization of ethylenically unsaturated compounds, characterized in that ionomers of the formulas (1) and / or (2), optionally with further ethylenically unsaturated Monomers, are polymerized. 3. The method according to claim 2, characterized in that the monomers of the formulas (1) or (2) immediately before the polymerization from alkali metal of the Acrylic or methacrylic acid and tetrabromo-meta- or ortho-xylylene dichloride are formed will. 4. Use of the polymers and copolymers according to Claim 1 as a flame cleaning agent for plastics or as flame retardant plastics.