WO2004016712A1 - Flame-proofing agent and means for the production thereof - Google Patents

Abstract

The invention relates to a flame-proofing agent based on a modified unsaturated oil to which other flame-inhibiting chemical substances such as boron and phosphorous compounds can be added in order to improve the flame-resistant properties thereof. The fungicidal qualities thereof are improved by adding terpenes to the mixture. The invention also relates to a method for the production of said flame proofing agents and the use thereof.

Description

Flame retardants and process for their manufacture

The invention relates to a flame retardant based on a modified unsaturated oil, to which further flame retardant chemical substances such as boron and phosphorus compounds are added to improve the flame retardant properties. The additive of terpenes also improves the fungicidal properties of the mixture. In addition, the invention also relates to a method for producing these flame retardants and their use.

It is known that native vegetable oils with a high proportion of unsaturated fatty acids can be used for a wide range of applications by integrating different substances with a splitting of the C = C double bond or in connection with the carboxyl group. This is especially true for the so-called quick-drying vegetable oils. The amount Unsaturated fatty acids are approximately the same in vegetable oils such as linseed oil, hemp oil, Iberian dragon's head, cra be and camelina, the difference being among other things in the proportions of different fatty acids and in the structure of the triglyceride. The number of double bonds available as reaction potential is therefore also different. Mixtures of these natural vegetable oils are also possible for the creation of targeted compositions of unsaturated fatty acids.

For linseed oil there are e.g. due to its properties, e.g. high creeping ability and high reactivity or polymerization ability due to the high proportion of unsaturated fatty acids with numerous

Double bonds diverse modification and optimization variants. The linseed oil is an ester of glycerin with various long-chain carboxylic acids, three fatty acids each being linked by the ester compound and thus forming the triglyceride. The proportion of unsaturated fatty acids in linseed oil is approximately 90%. Virgin linseed oil has a high flash point at 316-318 ° C.

In addition to the bromine, boron and phosphorus compounds mentioned, terpenes, for example in the form of pine and wood oils, are also added to the vegetable oil in order to develop flame-retardant properties. Due to their composition from a large number of different C compounds, pine oils are classified as essential oils. They mainly consist of terpenes (over 60%), which are composed of C ₅ H ₈ hydrocarbon units. Corresponding to these units, there are a large number of structures, of the most common monoterpenes with 10 C atoms, where also unsaturated, sometimes double or triple C compounds, e.g. terpene alcohol geraniol. These multiple bonds also form a reactive potential for the chemical reaction with halogens. Partial halogenation of terpenes cannot be excluded. Pine oil has polarizing properties, which have a positive effect on the reaction of a mixture together with vegetable oil when bromine is added, for example.

Modified vegetable oil can include can be used as flame retardants. The vegetable oil modified for this use can be used in pure form e.g. can be used by spraying on one material or as an additional component and additive in combination with other substances. The use of fire retardant modified vegetable oils is possible in numerous industrial areas. Especially in construction, components, materials and materials must be adequately flame retarded and given fire retardant properties through the use of flame retardants. Among other things, this applies for seals in building structures and for insulation in the building envelope. The modified vegetable oil can also be used as a flame retardant in the plastics sector for PVC, polypropylene and PUR products such as rigid and flexible foams. Here the flame retardant effect is shown through encrustation of the surfaces in the event of fire.

In the paint industry e.g. Linseed oil a wide

Used and with an additional fire-retardant function, the area of application can also be extended to special fire protection paints and varnishes. Other areas of application include technical textiles and numerous products made from renewable raw materials, such as chipboard and fiberboard, insulation and fillers. The boron compounds contained in the modified vegetable oil and the integrated terpenes have a flame-retardant effect as well as a fungicidal activity. This opens up a wide range of options for wood protection. In particular, the water-soluble boron compounds are used in products such. ^* B. Chipboard, which is subject to external moisture influences, is no longer dissolved and washed out in the product due to the connection with the vegetable oil. As a result, these substances retain their effectiveness in these products for a considerably longer period.

The flame retardant properties can be influenced by the degree of occupancy of the C double bonds of the unsaturated fatty acids. The vegetable oil with a high proportion of unsaturated fatty acids serves as a carrier material for the integrated flame-retardant and fungicidal substances. The complex integration of different flame-retardant materials creates different modes of action in the event of a fire. In the event of a fire, the H and 0H radicals necessary for the combustion mechanism are intercepted in the gas phase by a release of the halogens (bromine) and the HBr which forms and converted into H ₂ and H ₂ 0. This leads to a slowdown and the flame reaction is stopped. By contrast, phosphorus compounds, for example phosphoric acid esters, act in the condensed phase and promote charring by dehydrating the pyrolyzing substrate and thus reduce the emission of combustible gases. There can also be a protective layer on the surface, eg with

Plastics. This inhibits the burning decomposition products and can prevent energy absorption in the product due to its heat-insulating effect. The charring of the surface is also favored by the extensive C potential of the fatty acids. These systems mentioned start to work in conjunction with the vegetable oil at temperatures> 200 ° C. By integrating boron compounds, such as disodium octaborate, the effectiveness of the flame retardant can start at temperatures from 90 ° C, which means that particularly flammable materials are protected. The function of the borate is based on a glass-like protective film formation on the surface of the product, which creates an early thermal barrier and impedes the oxygen supply. The water present in the connection helps to cool and reduce the flame temperature. In addition to the flame-retardant properties, borates also act against insect and fungal attack.

The flame retardant from modified vegetable oil is characterized by the following behaviors, which have been shown when used in various applications:

a fire-retardant and retardant mode of action of the substance, when the body is removed from the source of the fire, the flames immediately extinguish, no complete ashing of the body when burned out, structure-preserving effect, with plastics there is no dripping of the burned substance, but a partial shows incrustation of the surface. Modified vegetable oil products that have stable material stability and are suitable for further processing without any signs of segregation in accordance with the technological requirements are required for the various uses and modes of action mentioned.

The usability of brominated vegetable oils ^; A number of patents already mention fire-retardants. DD-PS 230 709 (C 08 G 8/32) describes a process for the production of bromine-containing oil-modified phenolic resins which can be processed into flame-retardant laminates. For this, a partially brominated

Vegetable oil with a mass ratio 01 / bromine preferably of 10: 1, which corresponds to a degree of bromination of <0.1. This means that only a very small part of the double bonds are bound with bromine. The flame retardant effect achieved for the

Laminates can be assessed as rather low. Here the addition is among others a trialkyl phosphate mentioned as a plasticizer or flame retardant.

Some of the remaining double bonds in the vegetable oil are used for the reaction with phenolic resins. The laminates are subjected to heat and pressure treatment and harden in the process. The bromine-containing addition products are enclosed in the molding material. Flame retardancy occurs when exposed to heat. As a result of the inclusion of the active constituents in the hardened laminate, rapid use as a flame retardant cannot be achieved. DE-OS 3936 394 (C 08 G 8/32) describes a process for the preparation of modified phenol-formaldehyde resols. An oil-modified phenol-formaldehyde impregnating resin is produced by alkylating phenol with unsaturated, bromine-containing oils. The resin is used for printed circuit boards, but is not suitable for universal use as a flame retardant. Here, the low storage stability of a prior art is as - ^'partially brominated Tung oil or other oils mentioned as a disadvantage. The reason for this is considered to be the isomerization of the cis double bonds of (α-elaestinic acid not reacted with bromine for the more stable trans-configuration of the β-elaestinic acid. After the saturation concentration has been exceeded, precipitation from the oil can be observed after only a few days The storage stability is improved by adding a certain amount of an additional reactive unsaturated hydrocarbon, for example 20% by mass of styrene, although this addition can, among other things, impair the flame retardant function and can only be compensated for with a higher proportion of bromination.

In DE-OS 196 19 421 AI (C07 C 69/62) is a

Process for the bromination of unsaturated vegetable oils presented in which the addition reaction is carried out in the presence of a trialkyl phosphate or phosphonate. In this document, ranges from 50 to 100 parts by weight for the trialkyl phosphate or phosphonate to the oil and for a reaction temperature range up to 80 ° C., preferably 25 to 50 ° C., for the bromination are given. However, investigations have shown that the mixture ratio is not stable and homogeneous for the entire range given and at reaction temperatures above 20 ° C Solutions are expected. Reaction temperatures above the boiling point of bromine under free inlet conditions to the mixture are incomprehensible. The reaction taking place is exothermic and considerably higher temperatures can be expected in the bromination reaction center. The higher temperature ranges not only favor side reactions, which can be seen in the higher acid numbers of the reaction products, but there are also changes in the viscosity and inhomogeneity of the product. In the specified mixing ratios, there is a short separation between brominated fatty acids and partially brominated or non-brominated fatty acids. These unstable solution relationships are a major disadvantage of the claims shown.

The object of the invention is to develop a brominated, modified unsaturated oil which, in its effectiveness in the event of fire, builds up surface protection in the lower temperature ranges, has fungicidal properties and, as a result of the technological production, shows a stable, homogeneous material state.

This object is achieved by the generic flame retardant with the features of claim 1 and the generic method for producing a flame retardant with the features of claim 12. The respective subclaims show advantageous developments. The use of the flame retardant is characterized in claims 18 to 22.

According to the invention, a flame retardant based on a brominated and modified oil is supplied finished, which consists of a mixture of the following components:

a) at least one quick-drying unsaturated oil,

b) an essential oil containing terpene,

c) a phosphoric acid ester and

d) a boron-containing compound as a fungicidal component. The oils are at least partially brominated.

A vegetable oil is preferably used as the quick-drying unsaturated oil, of which linseed oil, hemp oil, Iberian dragon head, crambe and camelina are particularly preferred. The proportion of component a) in the flame retardant is preferably between 20 and 60% by mass.

The ethereal, terpene-containing oil is preferably selected from pine oil, pine oil, spruce needle oil, fennel oil, geranium oil, eucalyptus oil, camphor oil, bay leaf oil, mustard oil, lemon oil or a mixture of these oils. The proportion of the terpenes in component b) is preferably more than 30% by mass. The proportion of component b) in the flame retardant is preferably between 5 and 50% by mass.

Trimethyl phosphate, triethyl phosphate, tributyl phosphate, triphenyl phosphate, tricresyl phosphate, trismonochloroisopropyl phosphate, diethyl ethane phosphonate, dimethyl methane phosphonate or a mixture of these is preferred as the phosphoric acid ester. The proportion of component c) in the flame retardant is preferred between 5 and 30% by mass.

The mixture preferably contains a borate of the general formula I as the boron-containing component

R _n -2B _n 0 _2n -ι

with n = 1 to 12, where R is selected from the group consisting of methyl, alkali and alkaline earth metals and disodium octaborate tetrahydrate. The boron-containing compound is preferably present in a concentration between 2 and 30% by mass.

The process according to the invention for producing the flame retardant is based on four elementary steps:

I. First, a mixture of a fast-drying unsaturated oil, a terpene-containing essential oil, a phosphoric acid ester and a boron-containing compound is placed in a reaction vessel,

II. The mixture is cooled to a temperature of less than 20 ° C. using a cooling device,

III. the bromine is introduced via a dip tube, which is located in the immediate vicinity of the stirring element and

IV. The temperature of the mixture is kept below the boiling point of bromine by cooling during the introduction of the bromine.

A vegetable oil is preferred as the unsaturated oil, for example linseed oil, hemp oil, Iberian dragon head, Crambe and / or camelina. Pine oil, pine oil, spruce needle oil, fennel oil, geranium oil, eucalyptus oil, camphor oil, bay leaf oil, mustard oil, lemon oil or a mixture of these are preferred as the essential oil containing terpene. As phosphoric acid esters, trimethyl phosphate, triethyl phosphate, tributyl phosphate, triphenyl phosphate, tricresyl phosphate, trismonochloroisopropyl phosphate, diethyl ethane phosphonate, dimethyl methane phosphonate or a mixture of these are preferred. A borate of the general formula I is used as the boron-containing compound

R _n _ ₂ B _n 0 _2n _ι

with n = 1 to 12 preferred, where R is selected from the group consisting of methyl, alkali and alkaline earth metals and disodium octaborate tetrahydrate.

In the inventive method, linseed oil having an iodine value IZ will ^•> 180 g iodine / lOOg, pine oil, triethyl phosphate and disodium octaborate in the reactor vessel provided, mixed and cooled to a temperature of 10 ° C.

To get an optimal product, two

Basic requirements are created in the reactor. Neither concentration gradients nor temperature gradients may occur in the reactor, ie an excess of bromine may not occur at any point in the reaction mixture with regard to the free double bonds present, in order to prevent side reactions, mainly substitution reactions with the formation of hydrobromic acid. At the point of introduction of the bromine into the receiver, the risk of excess bromine is very high if the inflowing bromine does not break down as quickly as possible and distribute it evenly in the reactor becomes. Since the reaction temperature has a decisive influence on the quality of the reaction product, the heat of reaction generated can be removed quickly from the reaction mixture. At the bromine introduction point, an immediate division and

Mix with the template so that boiling and pressure surges do not occur at the inlet point due to the very fast and exothermic reaction of bromine with linseed oil. The temperature at the inlet point must be kept lower than the boiling point of bromine (58.8 ° C). An increase in temperature also favors the side reactions that occur. As a result, the breakdown of the incoming bromine stream and the mixing in the reactor are of great importance in addition to the temperature inside the reactor.

The dynamic viscosity of the mixture introduced increases exponentially with the degree of bromination and as the viscosity increases, the mixing time in the reactor also increases, which also makes the heat transfer from the reactor to the cooling jacket more difficult. Based on this fact and the requirement to achieve sufficient mixing, the dosing rate of the bromine changes depending on the viscosity of the product currently in the reactor. The metering rate at the beginning of the reaction is essentially determined by the cooling capacity of the reactor cooling. The dosing rate is reduced as the degree of bromination progresses. Experiments have shown that reaction temperatures above 20 ° C not only favor side reactions of the bromine, which can be seen in an increase in the acid number, but also favor the segregation of the product. For example, if bromination is carried out at 40 ° C, it tends to the product to separate within a few hours. In contrast, no segregation occurs in a product with identical mass fractions of the substances presented and bromine, which was produced at temperatures ≤ 20 ° C. The viscosity of the product made at 40 ° C is significantly lower than that of the product made at 20 ° C.

The C = C bonds of the fatty acids in the glyceride dressing of the untreated linseed oil are predominantly cis (Z) - configured. The presence of halogens can result in isomerization to trans (E) -configured C = C bonds, as shown in DE-OS 39 36 394. As a result of bromine addition to C = C bonds, the product formed by TRANS addition predominates. Fully brominated linseed oil is a solid that is only sparingly soluble in triethyl phosphate, i.e. From a certain concentration of the substances in the triethyl phosphate, brominated linseed oil precipitates in the form of crystals of approx. 10 μm. A colloidally disperse system is formed. If the brominated vegetable oil is present in high concentration in the triethyl phosphate, there is no sedimentation of the particles, since the sinking speed of the particles approaches zero. So you can adjust the viscosity of the product by varying the mass proportions of the substances involved. The product in which the equilibrium lies on the side of the trans (E) -configured CBr-CBr bonds is closer to the crystalline state than one

Product with ice (Z) -configured CBr-CBr bonds. This balance thus has a decisive influence on the viscosity of the product. A transfer and thus a shift in the equilibrium from trans (E) -configured CBr-CBr bonds to cis (Z) -configured CBr-CBr bonds can be achieved by drove, here temperature increase, possible. The cis (Z) - configured double bonds are closer to the liquid state. This explains the decrease in viscosity and the resulting sedimentation of the remaining solid. The effect of the decrease in viscosity also occurs when products which are stable against sedimentation are thermally treated for several hours, for example at temperatures above 50 ° C to 100 ° C. A pure linseed oil without additives, in which all C = C bonds have been brominated, has the same effect after heating at 100 ° C for several hours.

The viscosity is significantly reduced due to heating over a longer period of time. The process cannot be reversed by a thermal aftertreatment, for example a rapid cooling or melting of the product with subsequent rapid cooling. There is no change in the acid number due to the warming, so it can be ruled out that the triglyceride structure will dissolve because the amount of free fatty acids remains the same.

The bromine is introduced into the template via an immersion tube, which is guided vertically into the template and angled at the lower end. The outlet opening is located just above the stirrer in the direction of rotation of the stirrer. This type of introduction causes the inlet pipe to be sucked empty by the suction and negative pressure formed by the stirrer, thus preventing the inlet pipe from sticking to the product formed. Furthermore, this type of introduction of the bromine below the surface of the liquid has the effect that the bromine cannot rise up into the atmosphere of the reactor due to its density and the chemical reactions which take place immediately, and this thus is kept free of bromine vapors. The acid number is preferably reduced by adding a base. This simplifies the dosing and incorporation compared to deacidification with solids and it falls here

Product does not contain a solid that has to be removed by a technical aftertreatment, such as centrifugation. Hydroxides, oxides, carbonates or hydrogen carbonates of the alkali or alkaline earth metals are particularly preferably used as bases.

According to the invention, the maintenance of a narrow temperature range between 10 and 20 ° C, the lowering of the bromine dosing rate depending on the increasing viscosity, the introduction of the bromine near the stirrer below the liquid surface and the use of a liquid deacidifying agent to achieve a product with high material stability.

The flame retardants according to the invention are used as a component of insulation and fillers or seals. These flame retardants can preferably be used in chipboard or fiberboard. Likewise, however, it is also used as a component of plastics such as polyvinyl chloride (PVC), polypropylene (PP), polyamide (PA), polyethylene (PE), acrylonitrile-butadiemstyrene copolymer (ABS) or polyurethane (PUR). The flame retardant can also be used as a component of paints or varnishes in the paint industry and in wood preservatives.

The process for producing the flame retardant is to be explained in more detail using the following example, without the subject matter according to the invention restrict.

Example 1:

In a reaction vessel e.g. 25.0 kg (27.0 l) linseed oil with an iodine value IZ = 192 g iodine / 100 g, pine oil with 5.0 kg (5.8 l), disodium octaborate with 1.5 kg and triethyl phosphate with 16.4 kg ( 15.5 1) submitted. To achieve better solubility, the mixture can be heated to 60 ° C, mixed vigorously and then cooled back to a temperature of 10 ° C. The reactor is cooled by a combination of cooling coil and cooling jacket. The total amount of bromine to be added is 23.4 kg (7.5 l). The degree of bromination of the mixture can be adjusted according to the requirements for flame resistance. The degree of bromination in the example reaches BG = 0.80, i.e. H. 80% of the maximum addable amount of broth is added chemically.

After the start temperature has been reached, bromine is added. The bromine is supplied via an immersion tube, the end of which is angled in the direction of rotation of the stirrer and the mouth of which is arranged directly above the stirrer. This arrangement causes the inlet pipe for bromine to be emptied.

Since the viscosity increases exponentially with increasing degree of bromination and the mixing time in the reactor also increases with increasing viscosity, the metering rate during the bromination process is adapted to these circumstances. The first metering rate is, for example, 35 ml / min and is reduced in the course of the bromination in 10 steps to 8.5 ml / min depending on the degree of bromination. The dosing rate is reduced in the sense of an exponential function, ie the Plotting log (dosing rate) over the degree of bromination results in a straight line using the points (BG = 0; dosing rate = 35 ml / in) and (BG = 0.80; dosing rate = 7.3 ml / min).

This type of reaction procedure keeps the reactor temperature in the range between 10 and 18 °. The product has an acid number SZ = 4 mg KOH / g, a dynamic viscosity η = 950 mPa s (at 20 °), a light orange color and is stable against segregation.

Claims

claims 1. Flame retardant based on a brominated and modified oil available from a mixture a) at least one fast drying unsaturated oil, b) an essential oil containing terpene, c) a phosphoric acid ester and d) a boron-containing compound as a fungicidal component, the oils are at least partially brominated. 2. Flame retardant according to claim 1, characterized in that component a) is a vegetable oil. 3. Flame retardant according to at least one of the preceding claims, characterized in that component a) is selected from the group linseed oil, hemp oil, Iberian dragon head, crambe and camelina. 4. Flame retardant according to at least one of the preceding claims, characterized in that the proportion of component a) in the flame retardant is between 20 and 60% by mass. 5. Flame retardant according to at least one of the preceding claims, characterized in that component b) is selected from pine oil, pine oil, spruce needle oil, fennel oil, geranium oil, eucalyptus oil, camphor oil, bay leaf oil, mustard oil, lemon oil ^' or a mixture of these. 6. Flame retardant according to at least one of the preceding claims, characterized in that the proportion of the terpenes in component b) is more than 30% by mass. 7. Flame retardant according to at least one of the preceding claims, characterized in that the proportion of component b) in the flame retardant is between 5 and 50% by mass. 8. Flame retardant according to at least one of the preceding claims, characterized in that component c) is selected from the group trimethyl phosphate, triethyl phosphate, tributyl phosphate, triphenyl phosphate, tricresyl phosphate, trismonochloroisopropyl phosphate, diethyl ethane phosphonate, dimethyl methane phosphonate or a mixture of these. 9. Flame retardant according to at least one of the preceding claims, characterized in that the proportion of component c) in the flame retardant is between 5 and 30% by mass. 10. Flame retardant according to at least one of the preceding claims, characterized in that component d) is a borate of the general formula I R _n - ₂ B _n θ2n-l with n - 1 to 12 and R = methyl, alkali metal, alkaline earth metal and / or disodium octaborate tetrahydrate. 11. Flame retardant according to at least one of the preceding claims, characterized in that the proportion of component d) in the flame retardant is between 2 and 30% by mass. 12. A method for producing a flame retardant in which I. a mixture of a quick-drying unsaturated oil, an ethereal, tepren-containing oil, a phosphoric acid ester and a boron-containing compound is placed in a reaction vessel, II. The mixture is cooled to a temperature of less than 20 ° C. using a cooling device, III. the bromine is introduced through an immersion tube which is located in the direct vicinity of the stirring element and IV. The temperature of the mixture is kept below the boiling point of bromine by cooling during the introduction of the bromine. 13. The method according to claim 12, characterized in that it contains a mixture a) a vegetable oil, e.g. Linseed oil, hemp oil, Iberian dragon head, crambe and / or camelina b) as essential oil, for example pine oil, pine oil, spruce needle oil, fennel oil, geranium oil, eucalyptus oil, camphor oil, bay leaf oil, mustard oil, lemon oil or a mixture of these c) as phosphoric acid esters, for example trimethyl phosphate, triethyl phosphate, tributyl phosphate, triphenyl phosphate, tricresyl phosphate, trismonochloroisopropyl phosphate, diethyl ethane phosphonate, dimethyl methane phosphonate or a mixture of these and d) as a boron-containing compound e.g. a borate of the general formula I. R _n -2B _n θ2n-l I with n = 1 to 12 and R = methyl, methyl, alkali metal, alkaline earth metal and / or disodium octaborate tetrahydrate is used. 14. The method according to at least one of claims 12 or 13, characterized in that the viscosity is adjusted via the mass ratio between the mixture and added bromine. 15. The method according to at least one of claims 12 to 14, characterized in that with a deflection in the direction of rotation of the stirrer, the immersion tube is immersed in the mixture directly via the stirrer blades. 16. The method according to at least one of claims 1 to 15, characterized in that the reaction mixture is neutralized by adding a base. 17. The method according to claim 16, characterized in that the bases used are hydroxides, oxides, carbonates or hydrogen carbonates of the alkali or alkaline earth metals, 18. Use of the flame retardant according to at least one of claims 1 to 11 as a component of Insulation, fillers or seals. 19. Use of the flame retardant according to at least one of claims 1 to 11 as a component of chipboard or fiberboard. 20. Use of the flame retardant according to at least one of claims 1 to 11 as a component of plastics such as PVC, PP, PA, PE, ABS or PUR. 21. Use of the flame retardant according to at least one of claims 1 to 11 as a component of paints or varnishes in the paint industry. 22. Use of the flame retardant according to at least one of claims 1 to 11 as a wood preservative.