MATERIALS AND EXPANDABLE AND EXPANDED POLYSTYRENE MATERIALS SO MODIFIED The present invention relates to a modifier for expandable and expanded polystyrene materials, which improves the resistance of the final material, and in particular its thermal resistance, resistance to ultraviolet radiation and ozone and other weather conditions. The present invention relates also to expandable and expanded polystyrene materials so modified.

Expanded polystyrene (EPS) is a polymer material which is most frequently used in thermal insulation, e.g. in the construction industry. It is characterized, inter alia, by a very low thermal conductivity index and low density.

In order to enhance the resistance of EPS to the operation of ultraviolet rays and heat streams of high temperature, organic and mineral flame retardants and their compositions are used as well as factors and compounds released as a result of thermal decomposition of the components.

Styrene polymers, and expanded styrene polymers in particular, demonstrate very low resistance to heat streams of more than 85°C in which such polymers undergo physical, chemical and geometrical degradation; this - through passage into the liquid phase and loss of thermal insulation properties - may lead to the initiation of burning and also leads to their destruction .

A number of methods and preparations are known which reduce the flammability and enhance the thermal resistance of EPS with respect to its surface and weight but their effectiveness is insufficient. Additionally, in high temperature, well known and commonly applied preparations which reduce flammability and thermal resistance undergo pyrolysis thus leading to the pyrolysis of EPS; as a result, compounds are released which may additionally cause e.g. corrosion of metals, being also catalysers of combustion processes and toxic agents.

Well known and commonly applied solutions concerning the preparation of polystyrene-based materials, which enhance their resistance to high temperature, involve the application - as flame retardants - of compounds or compositions of compounds containing halides (e.g. HBCDD hexabromocyclododecane).

The above compounds or their simple compositions operate only in a temperature increased by their pyrolytic decomposition which results in the destruction, degradation or cracking of polystyrene the effect of which is its reduced flammability.

A group of compounds which also have an effect on the properties of materials are various types of dyes. There are very many requirements set for dyes, including non-toxicity, no negative impact on the polymer in which they are applied as well as their compatibility during parallel application with other additions such as plastifiers or flame retardants. A big group of synthetic dyes are alkaline dyes which yield intensive and vivid colour shades. These include xanthene dyes with a wide range of applications in the colouring of textiles, paper and wood, and also because of their fluorescence in chemical analysis and biochemistry.

German patent application DE4215391 presents new rhodamine dyes, based on 2,2,4, 8,10, 10-hexamethyl-6-(2-carboxyphenyl)-1 , 2, 3,4, 8,9, 10,1 1-octahydro- dipirido(3,2-a:3,2-g)xantylium salt.

They are applied in colouring polyacrylonitrile fibres, pigmenting polymers or inks. They can also be used in laser dyes or electrophotographic toners, and are characterized by enhanced resistance to light. Another invention US2006/0089422A1 describes polymer dyes containing a pigment which is covalently bonded with the polymer, a dye covalently bonded with the polymer, and a dispersant covalently bonded with at least one of the following: the pigment, the polymer or the dye. A derivative of the dye in the application is the 9-[4-(Chlorosulphonyl)-2-sulphophenyl]-3,6- bis(diethyloamino)xanthylium salt.

Considering the new legal regulations (certain compounds being included in the PBT classification; PBT - persistent, bioaccumulative, toxic substances) and the toxicity of the products of decomposition in pyrolysis and thermal transformations of some of the modifiers used to date as, e.g. preparations which reduce the flammability of polymer materials, it has become necessary to study the application of compounds whose decomposition products would be friendly to the natural environment and to humans and which would meet formal criteria and which, at the same time, would meet the expectations of the production and modification of polystyrene.

In expandable and expanded materials applied e.g. in the construction industry, exposition to long-term ultraviolet radiation and ozone of atmospheric origin results in the destruction of basic bonds in the materials, their depolymerisation leading to considerable changes in their resistance parameters and a change in the colour and smoothness of their surface, which has additional negative consequences in the form of an enlargement of their specific surface and porosity, increase in the generation of electrostatic charges which cause nuclei of radicals of endogenic fires leading to exogenic fires in objects.

Considering the general application of organic dyes, used e.g. in the textile industry, there was a need to check how this kind of compounds would affect the physico-chemical properties of polystyrene materials. It was particularly relevant to check whether dyes of the xanthene group would meet the expectations set during laboratory and application tests.

The subject of examination was therefore a modifier for expandable and expanded polystyrene materials, and materials so modified with the admixture of an agent based on synthetic alkaline organic dyes.

During laboratory tests on the composition and application of the modifier for expandable and expanded materials the flammability of the materials, the lambda coefficient, and the change in their electrical conductivity and pH have been examined. The aim of the invention is to provide a modifier for expandable and expanded polystyrene materials, improving the resistance of these materials to heat streams and eliminating the negative impact of ultraviolet radiation and ozone on the surface of materials used mainly in the construction and exposed to all sorts of atmospheric effects, through buffer transformation of energy streams with parallel reduction in the antipyrenes applied to date, which during pyrolysis and thermal transformations resulting in their decomposition, are transformed into toxic products. The aim of the invention is also to provide modified expandable and expanded polystyrene material, on whose surface, through modification with the modifier according to the invention, energy centres generated by the polymer are neutralized, especially in the form of electrical friction charges with a known (+ or -) like sign which is an abhesive bridge for protective layers on the modified styrene polymer surface concerned and thus electrostatic neutralisation, homogenization and adhesive activation occur on the surface of the styrene polymer, especially the expandable or expanded polymer.

The nature of the invention is a modifier for expandable and expanded polystyrene materials, characterised in that it contains a fluorescent organic dye of the xanthene group, in the form of 3,6-Bis(diethylamino)-9-[2- (ethoxycarbonyl)phenyl]xanthylium salt of between 0.1 and 100 parts by weight.

Preferably, according to the invention, the 3,6-Bis(diethylamino)-9-[2- (ethoxycarbonyl)phenyl]xanthylium salt is 3,6-Bis(diethylamino)-9-[2- (ethoxycarbonyl)phenyl]xanthylium chloride with the formula C30H35N2O3 CI:

Preferably, according to the invention, the modifier contains also:

- ammonia of less than 0.01 parts by weight,

- ethane-1 ,2-diol of less than 0.1 parts by weight,

- toluene sulphonamide formaldehyde melamine copolymer of between

99.0 parts by weight - water of more than 100 parts by weight with relation to 0.1 parts by weight of fluorescent organic dye of the xanthene group.

Preferably, according to the invention, the modifier is applied in the form of water dispersion of the density of paste or water suspension or in solid form with the granulation of between 0.4 pm and 15 pm.

The nature of the invention are also modified expandable or expanded polystyrene materials containing styrene polymer, organic blowing agents characterised by that they also contain the modifier of between 0.03 parts by weight and 2.9 parts by weight with relation to the polymer mass, containing a fluorescent organic dye of the xanthene group in the form of 3,6- Bis(diethylamino)-9-[2-(ethoxycarbonyl)phenyl]xanthylium salt. Preferably, according to the invention, 3,6-Bis(diethylamino)-9-[2- (ethoxycarbonyl)phenyl]xanthylium salt is 3,6-Bis(diethylamino)-9-[2-( ethoxycarbonyl)phenyl]xanthylium chloride with the formula C30H35N2O3 CI:

Preferably, according to the invention, the modified polystyrene materials contain also ammonia, ethane-1 ,2-diol, toluene sulphonamide formaldehyde melamine copolymer, water.

Preferably, according to the invention, the quantity of the modifier in the modified polymer is between 0.03 parts by weight and 2.9 parts by weight with relation to the styrene polymer. During laboratory tests on the production of expanded materials using the well- known method, with the use of the modifier according to the invention, and the production of these materials on semi-technological and technological scale with the application of the modifier according to the invention, it was unexpectedly found, that the operation of heat (temperature of 100 - 1 10°C) and pressure causes hydrophobic hardening of the dye complex, increasing the adhesive affinity during the blocking of expanded EPS and electron neutralisation of the EPS dendrite as well as reduced solubility of the dye fraction in water and reduced capillary penetration of water.

Ultraviolet radiation of between 320 - 390 nm is the most concentrated ultraviolet radiation posing a threat directly to the human eye and in particular the retina and the cornea.

In the cases of EPS, thermal insulation of buildings is commonly effected by manual placing of EPS panels on the surface to be insulated, with the application of various adhesive materials (water, polyurethane, cement glues). The resultant of the threats to the human eye is the level of reflection of the panel which is largely at the level of the worker's head. It was unexpectedly found that the glare, reflection of light against the surface of an EPS panel modified according to the invention is, considerably lower than in a standard panel.

When the modifier according to the invention is applied, there is an unexpected energy transformation of ultraviolet radiation, which is invisible to the human eye, into the phenomenon of colour fluorescence visible to the human eye in the form of the orange colour.

The phase complex resulting from thermal destruction of EPS in normal conditions, according to Gibbs' phase rule, transforms from the solid to the liquid phase with variable viscosity, being the carrier of the burning heat which may, in the form of a drop, cause an additional risk e.g. to the protection of rescue teams by causing, additionally, the spreading of fire. The use of a dye in the modifier according to the invention enabled considerable reduction in the fluidity and flammability of EPS, since reacting with the dye, the liquid phase of EPS (polystyrene) results in its coagulation. It was unexpectedly found, that the application of the modifier according to the invention to expandable and expanded materials, may result in an improvement of their thermal resistance (reduction in the lambda coefficient), mechanical parameters (resistance to compression, elasticity) and elastic recovery. The modifier according to the invention is presented in more detail in preferable examples of its production which, however, do not restrict its scope.

Example 1 Into a vessel with a mixing arm are introduced: 100 kg of styrene polymer intended for expanding and then, after the mixing arm is set to motion at a tangential velocity of 60 rev/min, 1 .4 kg of 3,6-Bis(diethylamino)-9-[2- (ethoxycarbonyl)phenyl]xanthylium chloride with the granulation of between 0.4 and 15 μιτι are put through spray nozzles. After all material is put in and after the lapse of 60 minutes, the mixing vessel is emptied.

After the mixing vessel is emptied, the material is homogenised further at a temperature of 20 ^° C for 10 hours, the modified styrene polymer according to the invention is obtained, which is expandable using the well-known method. Example 2

Into a vessel with a mixing arm (or by means of fluidal mixing) are introduced: 100 kg of preliminarily expanded granulate of styrene polymer and then, after the mixing arm is set to motion at a tangential velocity of 60 rev/min, 0.5 kg of 3,6-Bis(diethylamino)-9-[2-(ethoxycarbonyl)phenyl]xanthylium chloride with the granulation of between 0.4 and 15 pm are put through spray nozzles. After all material is put in and after the lapse of 60 minutes, the mixing vessel is emptied. After the mixing vessel is emptied, the material is homogenised further at a temperature of 20 ^° C for 10 hours, the modified styrene polymer according to invention is obtained. Example 3

Into a vessel with a mixing arm and a pump, are introduced: 8.6 kg of 3,6- Bis(diethylamino)-9-[2-(ethoxycarbonyl)phenyl]xanthylium chloride, 0,08 kg of ammonia, 0,9 kg ethane-1 ,2-diol, 1 10,6 kg toluene sulphonamide formaldehyde melamine copolymer and 1 kg of water and, after homogenisation at a temperature of 20°C, with the mixing arm set to motion at a tangential velocity of 60 rev/min, during 60 minutes, about 121 .1 8 kg of the modifier according to the invention is obtained in the form of a water paste to modify EPS using the well-known method before or after expansion. Example 4

Into a vessel with a mixing arm and a pump, are introduced: 6.0 kg of 3,6- Bis(diethylamino)-9-[2-(ethoxycarbonyl)phenyl]xanthylium chloride, 0.04 kg of ammonia, 0.5 kg of ethane-1 ,2-diol, 109 kg toluene sulphonamide formaldehyde melamine copolymer, and 3 kg of water and, after homogenisation at a temperature of 20°C, with the mixing arm set to motion at a tangential velocity of 60 rev/min, during 60 minutes, about 1 18.54 kg of the modifier according to the invention is obtained in the form of a water suspension to modify EPS using the well-known method before or after expansion. The loss in the mass of the material results from the external temperature and the quantity of water evaporation.

The modifier according to the invention may be put as a flame retarding and technological modifier at any stage of the processing of styrene polymer using the well-known methods, i.e. in styrene polymers to be expended; in styrene polymers after expansion; directly in styrene polymers before seasoning; in styrene polymers during seasoning (where the blowing agent is exchanged with air) or in expanded EPS immediately before it is put into the block-cutting machine and cut into blocks.

Owing the modification of styrene polymers according to the invention improvement of the tightness of the material in the block and geometric formats (after cutting) was achieved, the anisotropy of the medium was reduced, the resistance parameters (bending, compression, breaking), elasticity, memory of the shape, vibration and damping and noise suppression were improved, resistance to depolimerisation in oxygen, ozone and ultraviolet radiation, and stabilisation of the lambda coefficient were achieved.