DD212261A1 - METHOD FOR PRODUCING BROM AND TRIAZIN STRUCTURES CONTAINING FLAME PROTECTION AGENTS - Google Patents

Abstract

The invention describes a process for preparing flame retardants containing bromine and triazine structures with a bromine content of 3 to 50 and a nitrogen content of 2 to 10% by mass based on 2,3-dibromo-but-2-en-1,4-diol , Such compounds are suitable for permanent flame retardant equipment of condensation and addition polymers. In accordance with the aim of the invention to demonstrate a synthesis method which is easy to implement industrially for the preparation of reactive bromine- and nitrogen-containing flame retardants, 2,3-dibromo-but-2-en-1,4-diol according to the invention is obtained with methanol-etherified melamine-formaldehyde condensates, Polyols and paraformaldehyde in the presence of acidic catalysts at temperatures between 40 and 60 degrees C to below the gel point implemented. The resulting, at room temperature highly viscous to pastoesen products are in their functionality between 1.8 and 4.9 adjustable. They can be incorporated into both linear and branched condensation / addition polymers without disrupting the molecular structure and thus without restricting physico-mechanical properties.

Description

Title of the invention

Process for the preparation of flame retardants containing bromine and triazine structures

Field of application of the invention

The invention relates to a process for the preparation of bromine and triazine-containing flame retardants based on 2,3-dibromo-but-2-en-l, 4-diol. Such compounds are suitable for permanently flame-retardant finishing of condensation and addition polymers such as polyurethanes, polyesters and UP resins.

Characteristic of the known technical solutions

In addition to the flame-retardant finishing of polymers by additives, flame retardancy processes using reactive components whose composition and structure provide permanent flame retardancy have proven particularly useful. The chemical combination of the flame-retardant structural elements with the skeleton of the polymeric material avoids both the emigration of the flame retardant from the final product and its negative influence on the processing properties of intermediates.

A particularly high flame retardancy is achieved if combined simultaneously in the flame retardant various structural elements, which alone already cause a flame retardant

are. The synergistic effects which then occur generally permit a minimization of certain amounts of the flameproofing agent which would otherwise impair the properties of the polymeric material at a higher concentration.

The synergistic effect of various, the flame retardant ingredients can be achieved in the simplest case by the use of mixtures of different, in some already flame retardant components «For example, the problem solution according to DD-PS 100 274 by the simultaneous application of reactive and additive Flamraschutzkomponenten, wherein Reactive components Primary products of alkylene oxides with inorganic phosphorus compounds such as phosphorus pentoxide, phosphorus oxychloride and / or phosphoric acid and can be used as additive additives organic phosphorus, organic halogen and / or inorganic boron, antimony and aluminum compounds.

In DD-PS 150 750, the use of mixtures of bromine-containing polyether alcohols and inorganic components is described in an analogous manner, wherein a certain ratio of the heteroatoms is proposed to achieve a high flame retardancy · Further technical teachings include the following, flame retardant causing inorganic components: DE PS 2 542 288 and according to DD-PS 126 538 mixtures with silica, iron oxide, titanium dioxide, alumina, according to DE-PS 2 S40 749 Korabinationen of alumina hydrate with phosphorus compounds and according to DE-PS 2,542,499 mixtures with potassium carbonate, Aramoniumhydrogenphosphat and ammonium sulfate , The latter form in the thermal decomposition gaseous substances that contribute to reduce the development of toxic fumes in case of fire or at least cause dilution of the flue gases.

Mixtures of various organic compounds, such as 3is (2-chloroethyl) -2-chloroethylphosphonate with hexabrimocyclododecane (German Pat. No. 3,042,822), 2,2-butibromoldiol with organic phosphorus compounds (US Pat. No. 4,002,550) and preparations of halogenated and phosphorus-containing polyether alcohols, trichloroethyl phosphate and inorganic additives (German Pat. No. 126,446), dibromoneopentyl glycol and aluminum oxide (British Pat. No. 1,506,154) and brominated diphenyl ether, brominated diphenyl oxide and antimony oxide, zinc oxide, etc., (US Pat. No. 4,287,309) are further variants for flame retardants. r

Another way is in the cabination. thermal

stable structures with flame-retardant organic and / or inorganic additives isocyanurate with sulfur (German Pat. No. 2 422 647), polybrominated arcate with aluminum hydroxide and antimony oxide (British Pat. No. 1,456,805), tris-2,3-dibromo-propyl phosphate with etherified methylolmelamines (DE-PS 3,020,091, 2,845,572, US-PS 4,139,501), for the already flame-retardant properties are described (DO-PS 133 679, 137 239, 153 881, DE-PS 3 011 769, 3rd 109 929, US Pat. No. 4,221,875, EP-PS 0 040 720).

Another possibility is the synthesis of reactive flame retardants which have structural elements which effect several flame retardants. These include u. The helo-aryl-amide ester polyols according to US Pat. No. 3,974,109, halogenated urea derivatives according to DE-PS 2 912 074, bromine and chlorine-containing polyols (British Pat. No. 1,412,384), halogenated phosphopolyols (EP 0 024 791 ), propoxylated tribromophenol (U.S. Patent 4,149,987), a composition according to G3-PS 2 057 000 consisting of polyol, urea and chloral, halo-substituted melamines such as N, M ¹ -bis (1-hydroxy-2,2, 2-trichloroethyl) melamine (US Pat. No. 4,197,373) and analogous phosporph derivatives (US Pat. No. 4,140,660)

Object of the invention

It is the object of the invention to demonstrate a process which is technically easy to carry out for the preparation of Brora and nitrogen-containing reactive flame retardants which are suitable for the permanent flame retardant finishing of conventional condensation and addition polymers owing to the combination of two different heteroatoms and the resulting synergistic effect of the flameproofing.

Explanation of the essence of invention

The object is achieved by a process for preparing flame retardants containing bromine and triazine structures on the basis of 2, З-ОЬЬгога-Ьь ^ -г-еп-і, 4-diol, by using 2,3-dibrora-but-2-ene according to the invention -l ₍ 4-diol with methanol-etherified melaraih-formaldehyde condensates, polyols and parafonnaldehyde in the presence of acidic catalysts at 40 to 60 C and reduced pressure, preferably between 200 and 3000 Pa, are reacted below the gel point ·

The melamine-foraldehyde condensates used are 2-to Зкѳгпід and have an average of 3 methoxy-methyl and 1,2-methylol groups per triazine ring before the reaction »

The polyol used according to the invention is preferably alkoxylated polyhydric alcohols, such as propoxylated propane triol or trimethylolpropane, or else alkoxylation products of sorbitol or pentaerythritol, or polyester polyols or oligofonnal polyols.

The catalysts used are organic acids, such as p-toluenesulfonic acid or oxalic acid, inorganic acids, such as sulfuric acid, or activated cation exchange resins «

The process according to the invention is carried out in a stirred vessel. The mixture of dibromobutenediol, methanol etherified a malamine-formaldehyde condensate, polyol and

Paraforraaldehyde and acid catalyst forms a stirrable mass which is slowly heated. The reaction is carried out at temperatures between 40 and 60 ⁰ C. By applying a vacuum, preferably between 200 and 3C00 Pa, the formed by-products methanol and water are removed. Depending on the batch size, the reaction is stopped after about 30 to 60 minutes. For this purpose, an amount of alkali equivalent to the neutralization of the acid introduced as a catalyst is added shortly before reaching the gel point, and the mixture is stirred for a further 50 minutes. The salt load is then removed from the reaction mixture by filtration or centrifuging, leaving a product of yellow to brown color which is highly viscous at room temperature, pasty to brown. "

By varying the proportions of dibrorobutene diol, melamine-formaldehyde condensate and polyol, the bromine and nitrogen content and the degree of branching of the products can be set within wide limits. The products have a bromine content of 3 to 50% by mass and a nitrogen content of 2 to 10% by mass. The OH numbers are between 200 and 450 mg KOH g, or the average relative molin masses are between 300 and 1200 g mol "and allow the setting of functionalities between 1.8 and 4.9 Incorporated flame retardants obtained in both linear and branched condensation or addition polymers without disturbing the molecular structure of the products.

The anti-flaring effect of the products due to the synergistic effect of the heteroatoms is very good. For example, the classification Fire class 2 according to DIN 4102 and an oxygen index ^ 26 is certainly achieved when used in polyurethane systems.

The products according to the invention are stable on storage, even 8 weeks after mixing of the flame retardants with conventional polyurethane polyols changes

the reaction times in the polymer formation not observed. The physical properties of the final products are unchanged with respect to non-flame-retardant comparative samples.

Out of leadership examples

Example 1 -

In a stirred flask, 7.2 g of a methanol-etherified melamine-formaldehyde condensate (3 methoxy and 1.2 methylol groups per triazine nucleus) with the molecular weight 800 g raol " ⁴ ", 36.9 g of 2,3-but-2-bromobutyrone 1-l, 4-diol, 50 g of propoxylated propane triol (OH number 410-440) and 7.5 g of paraformaldehyde slowly heated under vacuum in the presence of 2 g of p-toluenesulfonic acid.

The transetherification and condensation on separation of methanol and water in a cooled template starts at 35 ⁰ C, After 30 minutes, the reaction at 57 ⁰ C (before reaching the gel point) by neutralization with the equimolar amount (based on p-Toluensulfonsiure) aqueous Potash solution broken off ·

The mixture is then stirred under vacuum for a further 50 minutes. After cooling to room temperature, the salt load is removed by centrifuging.

The light brown, strongly viscous product has the following characteristics:

-1

OH number

acid number

water content

molar mass

bromine content

nitrogen content

277 rg KOH g 0

0.23 % 515 gm mole 26.2 %

-1

2.1

CV / 0

AtSisi 2

Analogously to Example 1, 25 g of methanol-etherified melamine-formaldehyde condensate, 73.8 g of 2, 3-dibromo-but-2-en-1, 4-diol, 50 g of propoxylated propane triol and 15 g of paraformaldehyde are reacted in the presence of 3 g of toluenesulfonic acid , After 35 minutes, the reaction at 60 ⁰ C is canceled · The brown, highly viscous product has the following characteristics:

OH number acid number water content molecular weight bromine content nitrogen content

281 mg KOH g 0

0.54 % 530 g mol ""

r> с с / «3 ι O / 0

Example 3

17 g of methanol-etherified melamine-formaldehyde condensate, 100 g of 2, 3-dibromo-but-2-en-1, 4-diol, 50 g of propoxylated propane triol and 15 g of paraformaldehyde are reacted in the presence of 3 g of toluenesulfonic acid analogously to Example 1 The reaction is stopped at 55 ^° C. for 30 minutes.

pasty product has the following properties

The tawny shafts:

OH number acid number water content Moinasse bromine content nitrogen content

293 mg KOH g 0.49 mg KOH g 0.18 %

4SO g mol

2.2

-1

-1

-1

/ о

Example 4 to S

The procedure was in each case analogous to Example 2. The batch sizes and the obtained characteristic values are summarized in the following table:

Example 4 Example 5 Example 6

Batch size compared to Example 2

Max. Kondensationstemp. C

OH number mg KOH g

-1

Acid number rag KOH g " ¹

Molar mass g mol ~

bromine content

nitrogen content

3X

57

226

0.35

595

28.9

3.5

6 times 54

208 0.83 690 31.2 3.8

8x

53

0.31

520

32.4

4.1

Example 7

Analogously to Example 1, 25 g of methanol-etherified melamine-formaldehyde condensate, 73.8 g of 2,3-dibromo-but-2-en-1,4-diol, 50 g of oligoforraaldiol (Cooligomer of 1,3,6-trioxocane and 1 , 3-Oioxepan, molar ratio 1: 1, OH number: 77) and 15 g of paraformaldehyde in the presence of 3 g of toluenesulfonic acid

After 37 minutes, the reaction is stopped at 59 ⁰ C. The light brown, viscous product has the following characteristics:

OH number acid number water content molecular weight bromine content nitrogen content

197.5 mg KOH g 0.27 mg KOH g " ¹ 0.62 % 620 g mol '32.37 % 3.78 %

-1

Claims (4)

invention claim 1. A process for the preparation of bromine and triazine-containing flame retardants based on 2, S-oibromo-but-α-en-1,4-diol, characterized in that the 2, S-o-bromo-but-1-ene, 4-diol with methanol-etherified melamine-formaldehyde Kor.cansaten, polyols and peraformaldehyde, in the presence of acidic catalysts, reacted at 40 to 60 ⁰ C and reduced pressure and the reaction is stopped before reaching the gel point, 2. The method according to item 1, characterized in that the raethanolveretherten melamine-formaldehyde condensates contain an average of 3 methoxy-methyl and 1.2 methylol groups. 3. The method according to item 1 and 2, characterized in that are used as polyols polyether polyols, polyester polyols or Oligoformalpolyole. 4. The method according to item 1 to 3, characterized .. that are used as catalysts, organic acids, inorganic acids or activated cation exchange resins.