TREATMENT OF SURFACES AND SURFACE LAYERS

Abstract: The invention is an agent for the treatment of surfaces and surface layers of different materials, which comrpises as components a) polystyrol dissolved in a component b) of at least one alkoxysilane and/or a (partial) hydrolysis product and/or condensation product thereof, and if necessary as component c) a (silanol) polymerisation/condensation catalyst and possibly additives.

Description: Treatment of surfaces and surface layers This invention relates to an agent for the treatment of surfaces or surface layers of different material groups in order to improve their resistance to chemical and biological attack and to improve their physical properties. The invention is an agent for the treatment of surfaces and surface layers of different materials, which comprises as components a) polystyrol dissolved in a component b) of at least one alkoxysilane or a hydrolysis product or condensation product thereof and, optionally, comprises as components c) additives in the form of (silanol) polymerisation/condensation catalysts and surface active agents, pigments and similar. The treated surface may be nonporous. The treated surface or surface finish may be porous. The treated material may be organic or inorganic, rigid or elastic. In principle, it is the surface che ical/electrophysical properties of material surfaces which govern the material alteration processes, both the advantageous and non-advantageous ones. it is these properties, e.g. on particles of greater or lesser curvature or in capillaries, which determine the attraction and repulsion between different substances and combinations of substances, such as e.g. wetting on solid surfaces, the formation of droplets in emulsions, corrosion processes on metallic surfaces, biological attacks, the effect of different enzymes, salt degradation of solid materials, frost splitting, the adhesion of dirt to the surface finish, the adhesion of polymeric plastics to the fill material, e.g. to a granular or fibrous substrate, the adhesion in composite materials, and so on. It has now been found, surprisingly, that these (surface) chemical/ (electro)ρhysical properties of material surfaces can be radically changed/improved by coating surfaces with, or making surface layers of, polystyrene (polystyrol). Polystyrol has exceptionally good properties such as exceptional hydro- phobicity, electrical insulation capacity, chemical and biological resistance, clarity, resistance to alcohol and glycol, and so on. Poly¬ styrol is completely nonacidic and does not saponify. The spraying of polystyrol solutions and the processing of polystyrol is however extremely difficult. It is only with great difficulty that polystyrol can be combined with the other constituents in making a varnish - plasticisers can be used only to an extremely limited extent, polystyrol is so nonpolar that practically no solution is formed between the plasticiser and the polymer chain. It has been found, surprisingly, that the extraordinary properties of polystyrol can be retained and its processing disadvantages can be avoided by mixing/dissolving polystyrol in al oxysilanes. The agent in accordance with the invention for the treatment of surfaces or surface layers thus consists of or contains as component a) a poly- styrol and as component b) at least one alkoxysilane, and optionally as component c) a (silanol) polymerisation/condensation catalyst. The known technique for the production and use of polystyrol is described in the following. Styrol is a monomer (vinyl benzene); a polymer of styrol, known as polystyrol, is in accordance with known technique produced by means of mass, pearl, solution or emulsion polymerisation. The pure polymer is a transparent odourless and tasteless resin, a plas¬ tic, which is in principle only soluble in poisonous benzole and chlo¬ rinated hydrocarbons. Low molecular weight polystyrol is a substance which resembles an oil or balsam. Styrol and the polystyrol produced from this can be substituted by OH groups or alkyl groups, preferably by methyl groups. The molecular weight of polystyrol can vary over a wide range, between a few hundred to ca 250,000, with a preferred interval of 3000 - 50,000. In making polystyrol-containing preparations as components in the agent in accordance with the invention, the styrol can be copolymerised with nitrogenous compounds, for instance with acrylonitrile to produce acrylonitrile styrene, and with butadiene to produce acrylonitrile butadiene styrene, i.e. ANS and ABS. Other nitrogenous compounds which can be used for the copolymerisation of polystyrene are the previously mentioned acrylonitrile, fumaronitrile and vinyl carbazole. Polystyrols (as components) of improved physical properties are also produced with the aid of so called heterogeneous catalysts, so called isotactic polymers. Polystyrol can be modified by so called divinyl benzene. All these polystyrol variants can be used as components for the produc¬ tion of the agent in accordance with the invention. It has now been found, surprisingly, that this agent can be easily pro¬ duced by dissolving polystyrene in Λllroxysilanβε or mixing- pol/styrυl with alkoxysilanes by using porous polystyrol in expanded or pre- expanded form. ow oligomeric alkoxysilanes (dimers and trimers) and in particular monomeric alkoxysilanes are preferably used for this purpose. In conjunction with dissolution/mixing, it is also possible to use, in addition to pure polystyrol or its copolymers in the form of oils or resins, those products which are used as insulation or packaging materials or in the manufacture of these, namely pre-expanded or expanded pellets and similar products with or without a propellent gas, of a bul density between ca 10 and 50 kg/m 3 . Waste from packaging materials or waste from finished products contain¬ ing polystyrol, such as e.g. films and foils, hot moulded or injection moulded, (pre)expanded or extruded, solid or porous, products of differ¬ ent kinds, can be used as polystyrol. Different propel!ants such as e.g. pentane occur in intermediate pro¬ ducts such as e.g. pre-expanded polystyrol. rt has been found that this coating of material surfaces or treatment of surface layers can be carried out by mixing these polystyrenes in alkoxysilanes of the general designation SiR ' or π '-Si-R 4 _ π , where " is a C1-C6 alkoxy group, R' is a C1-C20 hydrocarbyl or halogenated hydrocarbyl group, R is a hydrolysable group such as e.g. C1-C6 alkoxy, and n is 1, 2 or 3, and that these silanes are monomers, dimers, trimers, oligomers or polymers thereof, whereby the polymer shall be in liquid form. The hydrocarbyl group R' consists of hydrogen and carbon atoms and may be a saturated or unsaturated aliphatic or alkyl group (preferably the latter), or cycloaliphatlc or cycloalkyl, or cycloaryl or cycloaralkyl. These hydrocarbyl radicals can also, as substituted groups, contain halogens such as e.g. chlorine, bromine, fluorine or nitrogen, oxygen or sulphur heteroato s, it being possible for one or more halogen substi- tuents to form part of the R' group. A preferred type of the hydrocarbyl group is C1-C12, with a further preferred hydrocarbyl group with C1-C6. Examples of such groups are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tertbutyl, pentyl, isopentyl, hexyl, octyl , isooctyl and decyl . Suitable aryl groups are phenyl and naphthyl groups which may also be substituted. The R group is a C1-C6 alkoxy, halogen, amino or carboxylate group. Cl- C6 al oxy is a preferred R group. The R" group 1s a C1-C6 alkoxy group. Special examples of silanes which can be used in accordance with this invention are as follows: methyltri ethoxysi1ane, methyltriethoxysi1 ne, methyltr1-n-propoxy- silane, ethyltrimethoxysil ne, ethyltriethoxysilane, ethyltri-n-propoxy- silane, propyl riethoxysilane, propyltri-n-propoxysilane, butyltrl- ethoxysil ne, butyltriethoxysilane, dibutyldimethoxysllane, isobutyl- trimethoxysilane, d-isobutyldimethoxysilane, Isobutyltriethoxysilane, n-hexyltrimethoxysilane, 6-chlorohexyltrimethoxysilane, 6,6,6-tri- f1uorohexyltrimethoxysi1ane, cyclohexylt imethoxysi1 ne, benzyltri- ethoxysilane, 4-chlorobenzyltriethoxysilane, 4-bromobenzyltri-n-pro- poxysilane, phenyltri ethoxysilane, phenyltriethoxysllane, octyltri- ethoxysllane, octyltriethoxysilane, octylmethyldi-isopropoxysllane, 1auryl rimethoxysi1ane, 2-ethyl exyltrimethoxysi1 ne, 4-chlorobenzyl- trimethoxysi1ane, decyltrimethoxysi1ane, dodecyltrimethoxysi1ane, tetradecyltriethoxysi1ane, hexadecyltriethoxysi1ane, octadecyltri- ethoxysilane, eicosyltrimethoxysilane, etc, as monomers, dimers, trimers, oligomers and polymers of these either on their own or mixed together. Preferred alkoxysilanes are alkyltrialkoxysilanes In accordance with the invention, both silanes and also their (possibly partial) hydrolysis products or condensates can be used. The silanes can be used in monomeric, oligomeric or polymeric form. Condensation products of silanes preferably have 2-10 Si atoms. The alkoxysilanes contained in the agent in accordance with the inven¬ tion react/condense/polymerise in the following way: The silane hydrolyses first (silanols), whereupon as a result of hydro¬ lysis it becomes condensable. These compounds are converted into so called (poly)hydroxy compounds. Owing to the fact that water is eliminated from these hydroxy groups in the polyhydroxy compounds, the latter are also made condensable, and copolymers can be formed. If heat is needed for the elimination of water, the reaction is referred to as pyrolysis. Hydrolysis and pyrolysis can occur after one another, but also simultaneously. The moisture required for hydrolysis may be present in the air in the environment. The moisture required for hydrolysis may also be supplied to the silane and the substrate by wetting in liquid, aerosol or vapour form, for instance, in practice, by superheated vapour. The condensation of the alkoxysilanes in the agent in the presence of moisture and/or the use of heat is accelerated by acidic or alkaline reaction conditions. These addle reaction conditions occur, for instance, in wood and wood based products. Alkaline reaction conditions occur in materials with inorganic binders such as cement, lime and similar. Reaction in the agent can also be accelerated by the addition to the agent in accordance with the invention, as components, c) known silanol, hydrolysis and polymerisation/condensation catalysts. The condensation catalysts in accordance with known techniques are e.g. organic peroxides or different amines. A preferred type of these catalysts are the so called metallic alcoholates and metallic acctylacetonates and alcoholates of silicon, SE Patent No 381453. All these alcoholates and acetylacetonates are produced by known techniques, preferably alcoholates of alkaline and alkaline earth metals, i.e. the first and second groups in the periodic system, preferably sodium, potassium, calcium and magnesium, but also alcoholates of metals from the third, fourth and fifth groups of the periodic system such as aluminium, tin, titanium, vanadium and zirconium. The alcohol component in these alcoholates is straight or branched alkyl alcohols with preferably 1-6 carbon atoms, for instance sodium ethylate,sodium isopropylate, potassiu -tert-propylate and magnesium methylate, isopropyltitanate, propyltitanatθ, propylzirconatβ, isobutylzlrconate and vanadylpropylate. Acetylacetonates are thereby manufactured by known technique, such as chelate complex, produced by reactions between metallic esters and chelates, such as e.g. beta-diketones, beta-ketonesters, beta-hydroxy or beta-a inoketones, and similar substances, e.g. B 564 179, US 3 153000.- These metallic acetylacetonates are made-from the metallic esters of the following metals: Aluminium, chromium (III), iron (III), cobalt (II), copper (II), magne¬ sium (II), manganese (II), nickel (II), vanadium (III), vanadium (IV), zinc (II), tin (II), zirconium (IV), titanium (IV). The term alcoholates is to be taken to refer to silicic acid esters, condensates or di lkaline salts thereof. The ester component shall thereby comprise alkyl residues with 1-8 carbon atoms and/or onocyclic or bicyclic phenyl residues or cycloalkyl residues with up to 8 carbon atoms. The condensate products are partial hydrolysis products with preferably 2-lO-/S1-0-/units per molecule. The agent in accordance with the invention may also contain other hydrolysis catalysts, for instance salts between metals and carbonic acid or hydroxycarbonic acid, a mixed organometallic compound (in which at least one organic residue is, via a carbon atom, directly coupled to the metal atom and in addition at least one residue or ion is coupled, not over a carbon atom, to the metal atom). Salts of cadmium, titanium, zirconium, tin, lead, manganese, iron and cobalt, such as e.g. tin(II) octoate, lead octoate, lead laurate, iron (III) octoate, iron(II) stearate and cobalt naphthenate, can be used as such catalysts. Organometallic compounds such as e.g. dibutyl tin dilaurate and dibutyl tin diacetate are also suitable (e.g. CH 594576). Another preferred type of catalyst which may form part of the agent In accordance with the invention are organofunctional silanes with basic organo groups (SE Patent 381453). The organofunctional silanes with basic organo groups comprise alkoxy¬ silanes with one or two alkyl or aryl groups directly bonded to the silicon atom, at least one of which should possess residue υf alkaline reaction, such as amino groups. Such an amino group may also be substituted, provided that the substi¬ tuted amino group in its entirety still has an alkaline reaction. The alkyl group bonded to the silicon ' atom is preferably one with 3-6 carbon atoms, while the aryl group is preferably the phenyl group. Examples of such compounds are: / 9-amino-α-methyl-ethyltriethoxysilane, 7 -aminoproρyltriethoxys11ane, δ-aminobutyltrimethoxysilane, ω-aminohexyltriethoxysilane, 7-amino- propylmethyldiethoxysilane, -y-amlnopropylphenyld1ethoxysilane, N-petyl- 7 -aminopropyltriethoxys11ane, N,N-di ethyl- 7 -aτπinopropyltr1ethoxys11ane, N- 7 -aminogropyl-Λ-aminobutyltriethoxysilane, N-^-aminoethyl- 7 -amino- propyltriethoxysilane, N-( 7 -tri-ethoxysllylpropyl)-aniline, N-methyl-N- (7-triethoxysilylpropyl)-aniline and N-( 7 -triethoxysilylpropyl)- -naph- thyl-amine. These catalysts promote hydrolysis and condensation of the silanes contained 1n the agent 1n accordance with the Invention. The alcoholates and acetyl cetones and silanes with organofunctional groups can also modify the substrate or the layer between the substrate and the applied hardened agent in accordance with the invention. and the agent in accordance with the invention physically and chemically, for in^t.anrp hy Pnhanrpmpnt nf arlhp<5i nn nr hy imprnvpmpnt nf t.hp rhpm-i ral resistance of the treated substrate to different aggressive media. Reaction in the agent in accordance with the invention can be retarded by polymerisation retarders in accordance with known technique, e.g. hydroquinone. Surface active preparations/emulsifiers can be added to the agent 1n accordance with the invention or to preparations made from the agent. These surfactants may be cationic, anionic or nonionic. The surface active effect of these surfactants may be temporary, i.e. the surfactant may be degraded by alkaline or acidic conditions, atmos¬ pheric oxygen, heat and similar. These surfactants can be dissolved in the agent in accordance with the invention or in vehicles. Other components such as different biocides (microbes, fungi), anti- corrosion agents, lubricants, odorants, thickeners, plasticisers, colorants and similar can be added to the agent in accordance with the invention by known technique. Granular or fibrous/filamentous filler material, both organic and inor¬ ganic, can be added to the preparation as pigment. It has been found, surprisingly, that the corrosion process on certain metals (bronze, copper, lead) can be beneficially influenced by mixing graphite powder into the agent in accordance with the invention. The agent in accordance with the invention can be used as a concentrate, as a solution, emulsion, suspension, in aerosol or gaseous form. However, all liquid preparations can be used as vehicles for the agent in accordance with the invention if the agent in accordance with the invention is suspended/emulsified. Examples of such vehicles, apart from water, are organic solvents. These include, inter alia, aliphatic and aromatic solvents. Monovalent or polyvalent alcohols, ketones, esters and ethers can be used as aliphatic solvents. Alcohols which can be used are ethanol, ethanol, propanol , isopropanol, butanol , glycol , propylene glycol, butylene glycol and glycerine. Examples of ketones which can be used are acetone and methylethylketone. Examples of suitable esters are acetic ester with polyvalent alcohols such as glycol and glycerine. Usable ethers include ethylene glycol monoethyl ether and ethylene glycol monomethyl ether. Examples of aromatic solvents which can be used are benzole, xylol, toluol, white spirits, turpentine substitute, styrol and similar. Ketones, esters or ethers are preferably used as solvents. These solvents are known to professionals. The production of conventional types of emulsions and suspensions of the agent in accordance with the invention is also known to the profess¬ ionals. It should be pointed out that vehicles/solvents may dissolve the silane component b) and the catalyst component c) out of the agent in accord¬ ance with the invention, but not the polystyrol components a), one way of making suspensions of polystyrol. Mixing of the agent in accordance with the invention with a solvent that does not dissolve polystyrol a) but dissolves the alkoxysilanes b) thus causes a suspension of polystyrol a) to form. The stability of polystyrol solutions in alkoxysilanes decreases as the concentration of polymerisation catalysts increases. The polystyrol a) in silane solutions b) with high concentrations of polymerisation catalysts c) initially condenses by forming some form of suspension. Another way of making suspensions of polystyrol particles in vehicles is thus to increase the concentration of polymerisation catalysts in the agent in accordance with the invention, which results in condensation/ polymerisation of the polystyrols dissolved in the agent in the form of a precipitate. The components making up the agent 1n accordance with the invention may have different solubilities in different solvents. If this 1s an inconvenience, the agent in accordance with the invention can be applied in different treatment stages and with different compo¬ nents in the ageπt/solvents/vehicles in the different treatment stages. The agent in accordance with the invention can be mixed with other liquids which may be solvents or vehicles (for suspensions, dispersions, emulsions and similar). The different components of the agent may have different solubilities in relation to other liquids: a solvent may for instance be able to dissolve only a limited number of components of the agent in accordance with the invention. The different components of the agent 1n accordance with the invention can be dissolved in different solvents and mixed with different vehicles. These mixtures/solutions of the individual components can be applied to the treated surface/surface finish on their own. In the simplest case, mixing of the individual components into an agent in accordance with the invention occurs after application by diffusion. Polymerisation reactions which have commenced and are i.n progress 1n a layer spread to other adjoining layers. As pointed out before, aliphatic or aromatic solvents can, apart from water, also be used as vehicles for the agent or its individual compo¬ nents or mixtures of components. It has been found, surprisingly, that it is possible to avoid precipita¬ tion of polystyrol in the form of suspension/emulsion due to the addi¬ tion of a catalyst or preparation which does not dissolve polystyrol by applying the agent in accordance with the invention, containing cata¬ lysts as additives, in two or more stages, first a treatment with silane and possibly a solvent and additives containing a catalyst, and then either immediately or after a certain time, application of polystyrols dissolved in the silane, possibly with a solvent compatible with poly¬ styrol . If this two phase application of the agent in accordance with the invention, containing catalyst, is employed, a solvent which does not dissolve polystyrol can also be added to phase 1, namely silane and catalyst. This implies that the agent in accordance with the invention, comprising polystyrol a), silane b), catalyst c) and solvent which does not dissolve polystyrol or the polystyrol solution, can be applied in two stages, for instance Stage 1 solvent and catalyst, Stage 2 polystyrol and silane, or Stage 1 solvent and catalyst and silane, Stage 2 polystyrol and silane, or Stage 1 silane and catalyst, Stage 2 silane and polystyrol, or Stage 1 catalyst, Stage 2 silane and polystyrol. If necessary, different silanes or/and solvents/vehicles are used in Stage 1 and Stage 2, whereby, for instance, a silane in Stage 1 may be a (possibly) partial hydrolysis product (precondensate). In all these cases the polystyrol may be dissolved in polystyrol compa¬ tible solvents. The sequence of treatment, Stage 1-Stage 2, for surfaces or surface layers in these examples of two stage application of the agent , may as and when necessary be reversed. A preferred procedure for the application of the agent, containing three components a), b) and c), is thus to apply the agent in at least two stages, whereby the dissolved polystyrol, component a), and the (silanol) catalyst used, component c), shall not occur in the same stage of the treatment, i.e. in the same mixture of the individual consti ¬ tuents of the agent. The mixing proportions of polystyrol/silanc can vary over a broad range. When the concentrations of styrol/polystyrol in the silanes are low, the solution is clear and has low viscosity; the solution/mixture can be applied by known techniques for the application of liquid materials. When the silane concentrations in polystyrol are high, the mixture/ solution has high viscosity, whereby these high polystyrol/sil ne con¬ centrations can be obtained by evaporating the silane from low concen¬ tration polyεtyrol-cilano solutions nr hy dissolving DOlystvrol by silane vapour/aerosols. The solution can be applied by all known techniques, e.g. those known from working with filler compounds. Mixing can be carried out accompanied by heating, with e.g. heated or molten polystyrol and/or polystyrol in aerosol form. The solubility of polystyrol in the al oxysilanes decreases as the degree of hydrolysis and condensation of silane Increases. It is lower for oligo ers (and liquid polymers) than for monomers. A hypothesis regarding the mode of action of the mixture may be that the alkoxysilanes chemically or physically, possibly after hydrolysis/pyro- lysis and condensation, "attach" themselves to both the polystyrol com- ponent and to the organic or inorganic substrate, particularly when these contain hydroxyl groups, metallic oxides or similar. Adhesion between the agent, its different components or a substrate can be improved by so called adhesion promotion silanes such as etacryl , glycidyl, vinyl silane as pretreatment of the substrate or as an addi¬ tive to the components of the agent according to known techniques. The effect of the agent in accordance with the invention is partly due to the fact that the silanes contained in the agent hydrolyse/pyrolyse and condense into polymers. •- It is not known whether some copolymerisation takes place between the silanes and the polystyrol dissolved in the silanes. Hydrolysis is initiated by moisture, possibly atmospheric humidity or water vapour, which is present in or added to the processes in question, e.g. via a moist substrate, water in the vehicle or similar. Pyrolysis of the silane contained in the agent in accordance with the invention can be brought about by heating the substrate which may in a previous treatment stage have already been partially treated with some phases/ components of the agent in accordance with the invention, or by heating the environment adjacent to the surface/surface finish to be treated. Condensation and polymerisation of the silane can also be brought about by the application of heat, pyrolysis, at a temperature ranging between 100 * C and 600 C C depending on whether polystyrol is simultaneously pre¬ sent, preferably within the interval 100-200'C. The agent can be heated, for instance, by means of high frequency radia¬ tion, with microwaves or by infrared radiation. High frequency radiation accelerates the condensation of hydrolysed silanes, affects water but not plastics such as components a) and b) of the agent, polystyrene and (polymerised) silane (silicon). If fibres and yarn or woven material made from these are treated with the agent in accordance with the invention, the fibres, yarn or woven material may after the separate treatment stages or at the end of the treatment be dried. Drying can be carried out by the use of heat in accordance with known technique or/and by surplus water being forced out of the fibres by a pair of rolls or compression plates or centrifuging or similar, and/or by contact with a current of air or gas,- with drying occurring through heat and/or convection. The agent and its components can be applied in concentrate form, in the form of solutions, suspensions, emulsions, all these forms may also be in the form of aerosols or gases. The agent and its individual components a), b) and optionally c) can after prior vacuum treatment be applied to a substrate by a procedure in accordance with known techniques, such as immersion, brushing, rolling, dipping, spraying, impregnation, drawing through or storing in liquids, gases, vapours or aerosols, possibly by using overpressure, in the form of concentrate, solutions, suspensions, dispersions, emulsions, aero¬ sols, gases and vapours, in different treatment stages. Depending on the quantity applied, the applied and fully reacted and hardened agent in accordance with the invention 1s in the form of a membrane, film or a coating. In order that a thick coating should be obtained, the agent in accordance with the invention or its components - possibly in suitable mixtures with suitable additives - can be applied in several stages/layers. The principal components of the agent in accordance with the invention, namely silanes and polystyrol, can be mixed in greatly varying propor¬ tions. If the agent is to be used in the form of a liquid preparation of low viscosity, the weight of polystyrol is to be between 0.1 and 50% of that of the silane, preferably 0.1 - 25%, with a preferred interval of 1-15%. If the agent in accordance with the invention is to be used as a filler compound or a binder, the weight of the polystyrol may be between 50 and 100% of that of the silane. The weight of catalyst in the agent is 0.1-10% of that of the silane, with a preferred interval, of 1-5%. The weight of the surface active additive to the agent in accordance with the invention is 0.1-15% of the weight of the agent, with a preferred interval of 1-10%. The effect of the agent in accordance with the Invention is shown in some examples, the biological effect In Example 1, the electrophyslcal effect in Examples 2 and 3, and the chemical improvement 1n Example 4. Example 1: Treatment of wood against attack by mould Example 2: Treatment of bronze surfaces Example 3: Reinforcing steel Example 4: Treatment of glass fibre and improvement of its alkali resistance. The agent in accordance with the invention can be used for the treatment of intact surfaces and surface layers but also for the treatment/ strengthening/improvement of degradation products and corrosion pro¬ ducts, e.g. caused by an aggressive environment on these surfaces. The bioddal effect of the agent in accordance with the invention, which is presumably largely due to its polystyrol content, can be used for the treatment of organic substrates such as e.g. wood or. wood based pro¬ ducts, textiles and similar, but also for many mineral materials which are attacked by microorganisms, particularly certain bacteria, such as e.g. natural stone and structural concrete. The agent in accordance with the invention can be applied to material surfaces or surface layers of different shapes, for instance in the form of sheets, bars, profiles, yarn, fibres, granules and woven fabrics and composite materials, made from materials in this form. The agent in accordance with the invention can - possibly together with organic or inorganic fillers in the form of powders or fibres - be used as a binder in producing aggregate material, both organic and inorganic. Depending on the quantity applied, the applied and fully reacted and hardened agent in accordance with the invention is in the form of a membrane * film or a coating. In order that a thick coating should be obtained, the agent in accordance with the invention or its components - possibly in suitable mixtures with suitable additives - can be applied in several stages/layers. The adhesion to these materials can, as already pointed out, occur by chemical coupling of the alkoxy groups and a substrate, after hydro- lysis/pyrolysis and possibly condensation. Adhesion to a substrate can also occur by physical adhesion of a film which has formed after the alkoxysilanes had hydrolysed and condensed. The agent in accordance with the invention, after the reactions had ter¬ minated after hardening, thus easily adheres to surfaces and surface layers of glass and ceramic products, mineral (building) materials such as mortar, concrete, brick, natural stone, inorganic aggregate material and fillers for organic binders (plastics, adhesives and similar) and inorganic binders (containing lime, gypsum, salts, different types of cement) and metallic surfaces (metallic oxides or corroded surfaces and surface layers). The agent in accordance with the invention can be used for the treatment of metallic surfaces in structures or structural elements of e.g. iron, steel, aluminium, copper, bronzes with oxidised oxidised or corroded (porous) surfaces, containing salts, oxides or hydroxides in the form of patina or rust. One example of the treatment of such surfaces is the conservation of outdoor bronze statues .against an aggressive environment or the treat¬ ment of reinforcing bars in concrete structures as protection against e.g. corrosion initiated by chlorides. The preparation in accordance with the invention can also be applied to cellulosic materials, and preferably to wood in all forms and to pro¬ ducts made from wood (sheets, granules, filaments, fibres). It should be pointed that the preparation in accordance with the inven¬ tion has great antimicrobial effect. It may be proposed as a working hypothesis that this antimicrobial effect is due to the phenyl groups in polystyrol. In some way, polystyrol resembles a substance designated stilbene which occurs in the heartwood of different kinds of trees and is an extremely effective agent against mould, decay fungi and bacteria. The preparation in accordance with the invention can be used to prevent microorganisms from attacking different materials or to stop a microbial activity already in progress. The agent in accordance with the invention is suitable for the treatment of both organic and inorganic fibres made by known techniques and pro¬ ducts made from these (textiles, paper and similar). The fibres can be used for the strengthening (reinforcement) of organic and inorganic composite materials together with cement mortar, gypsum and similar, and plastics. Among inorganic fibres may be mentioned fibres of glass, asbestos, mineral wool and rockwool and products made from these (sheets, mats, yarn, ropes, woven fabric and similar). Glass fibres or products made from these which shall be treated in accordance with the invention may be made of any glass such as e.g. soda/1ime/silicium dioxide, aluminium silicate or boron silicate (E- glass) or special glasses such as alkali resistant (zirconium silicate) glass, so called AR glass, e.g. GB 1 290 528. The glass normally used is commercially available glass which is in most cases surface treated with different preparations such as starch, diff¬ erent plastics or amino, glycidil and metacryl silanes (inter alia dissolved in water) in filament production treated after the nozzle, e.g. SE 422935. The agent in accordance with the invention can be applied to many of these surface modifications. The treatment can improve the adhesion of the hardened agent to the sub¬ strate, e.g. of inorganic material. This surface modification can if necessary be removed by solvents or heating. Example 1. The protection of wood against moulds Treatment of wood by the composition consisting of or containing polystyrene dissolved in an alkoxysilane in combination with a catalyst protects wood against attack by microorganisms, especially moulds, and prevents further deterioration of wood already attacked by moulds. Two samples of wood which were already slightly biodeteriorated by moulds (Aspergillus and Penicillum) were taken. One of the samples was immediately treated with a preparation consisting of 2% polystyrol in a solution of propyltrimethoxysilane (monomeric). The polystyrol was a cellular plastic, Swedish trade mark Frigolith of ddeennssiittyy 3355 kkgg//mm uusseedd ffoorr iinnssuullaattiioonn oof buildings, the propyl trialkoxysilane was from Hϋls, Troisdorf FRG. No catalyst was used, the polymerisation of silanes was accelerated by acid reaction conditions in the wood surface (pH 5.0), Sample 1. The other sample was allowed to be further deteriorated by moulds, and after a few months exhibited heavy biodeterioration, Sample 2. After six months of treatment of Sample 1 the following effects could be noted: Water uptake as a measure of biodegradation increased in Sample 2 (Sample 2, column 1). In Sample 1 the attack by microorganisms was halted as could be seen by the reduced water uptake of Sample 1 after 6 months (Sample 1, columns 1 and 2). When Sample 2 was treated after 6 months' of attack by moulds, the attack by microorganisms was also halted as could be seen by the reduced water uptake in Sample 2 after a further 2 months. The properties of the samples and the results of treatment are summarised in Tables 1 and 2. Sample 1 Water uptake by Sample. 1 as a function of the time of contact with water. Sample 1 treated immediately after felling. Column 1 water uptake prior to- treatment, slightly biodeteriorated surface. Column 2 water uptake 6 months after treatment. Column 3 time of contact with water. Untreated Treated wood, Time wood % silane+polystyrene % h 32.1 10.9 2 46.1 13.0 4 54.0 13.9 6 57.0 14.0 8 60.0 14.0 10 63.0 14.0 12 65.0 14.0 14 66.0 14.0 16 68.0 14.0 18 69.0 14.0 20 65.0 14.0 22 69.0 14.0 24 Table 1 Sample 2 Water uptake in Sample 2 as a function of the time of contact with water. The sample was allowed to undergo biodeterioration for a further 6 months after felling. Sample 2, heavily biodeteriorated, was treated 6 months after felling. Column 1 water uptake after 6 months prior to treatment. Column 2 water uptake 2 months after treatment (8 months after felling). Column 3 time of contact with water. Untreated Treated wood, Time wood % silane+polystyrene % h 62.0 • 8.0 2 87.2 11.0 4 110.0 12.0 6 120.0 12.0 8 130.0 13.0 10 140.0 14.0 12 147.0 15.0 14 152.0 16.0 16 155.0 16.0 18 157.0 16.0 20 159.0 16.0 22 163.0 16.0 24 Table 2 Example 2. Protection of patina layer on copper alloys Valuable works of art made from different alloys such as different types of bronzes, brass, lead, tin are sometimes heavily deteriorated by the effects of an aggressive environment such as acid rain, nitrogen compounds and so on. The results of this attack are ugly coatings on surfaces, consisting of mineralic matter such as various salts of copper, mostly basic copper compounds. The same mechanisms can be seen on copper roofing sheets. Deteriorated samples from copper roofs can be used to study the effects of the mechanisms <_f deterioration and to evaluate the effect of corrective measures. The effect of corrosion of copper (and bronzes) can be measured in terms of an electric potential. The effect of treatment can be measured in terms of a change in the electric potential after treatment. The following treatment was used. The corroded surface layer which is porous was painted to saturation by a composition consisting of polystyrene in alkylalkoxysilane with a catalyst as additive, optionally with the addition of a fine graphite powder. 5% by weight expanded polystyrene (trademark Frigolith) density 50 kg/m 2% by weight titanium acid ester, titanium tetraisobutylate, Huls Troisdorf FRG 1% by weight graphite, industrial quality, optional, in i obutyltrialkoxysilane (Huls Troisdorf FRG). The protective effect of treatment with polystyrene in alkyl- alkoxysilanes (monomeric) with the addition of catalysts/titanium acid ester and optionally a fine powder of graphite can be seen in Table 3 in terms of potential measurements. The treated surfaces could not be etched by droplets of 1% sulphuric acid and 1% hydrochloric acid. The corrosive effect of patina formations and their treatment Surface Treatment Potentiometer Potential Remarks reading, mV mV Ground copper, untreated +98.5 +338.5 Theor. +337 mV bright Copper(I) oxide untreated +40 .0 - +35.6 +280.0 Brown corrosion untreated +84.0 +324.0 Green coating product, porous removed Green patina untreated +54 .0 - +53.5 +294.0 Three layers complex, porous Black patina .untreated +22.0 +262.0 On brown layer complex, porous x) Black patina untreated -25.0 +215.0 Three layers complex, glassy XX) Green patina impr complex, porous K 4 Fe(CN) 6 +12. 0 - +6.0 +249.0 Green patina impr -39.6 +201.4 complex, porous K 4 Fe(CN) (alkylsilane, polystyrene) Green patina impr -24.0 +216.0 complex, porous (alkylsilane, polystyrene) Green patina impr c-300.0 <-60 XXX) complex, porous (graphite, alkylsilane, polystyrene) Remarks The electrode used was a calomel electrode with a given potential of +240.0 mV The samples used were copper sheets obtained from debris of recent repair work on roofs and towers in x) Royal Castle in Stockholm (100 years) xx) City Hall in Stockholm (1923) All other samples from a church in Stockholm xxx) Reading out of voltmeter range Example 3. Protection of steel aσainst corrosion Reinforcing bars in steel are corroded by aggressive salts such as chlorides in de-icers and in sea water. Certain critical values of pH, the electric potential of the surfaces and the presence of oxygen and an electrolyte such as water are prerequisites of corrosion. Reinforcing bars in an aggressive environment can be protected by coating. Many of these are plastics which are not resistant to chemical attack. Reinforcing bars were coated in two stages, priming (pretreatment) of the rusty reinforcing bars by a solution of 1% by weight of titanium acid ester (titanium tetraethylate) in alkylalkoxysilane (isobutyltrimethoxysilane), all by Huls, Trois¬ dorf FRG final coating applied immediately after priming, consisting of a solution of insulating grade polystyrene of 30 kg/m 3 density (from packaging waste), 15% by weight of isobutyltrimethoxysilane. The effect of treatment can be determined by comparing the potential on rusty and treated surfaces and bright and untreated surfaces of 12 mm diameter reinforcing bars. A voltmeter with graphite electrodes was used, the positive and negative electrodes being attached to the two ends of bars whose properties are set out in Table 4. Table 4 Property of Property of end 1 end 2 Bar 1 1.1 rust 1.2 bright Bar 2 2.1 rust, treated 2.2 bright The potential differences measured are set out in Table 5. Tabl e 5 Rusty end 1 Bright end 2 Potential difference mV Untreated bar 1 1.1 - pole 1.2 + pole - 280 1.1 + pole 1.2 - pole + 10 - 290 Treated bar 2 2.1 - pole 2.2 + pole - 30 2.1 + pole 2.2 - pole - 260 + 230 The treatment considerably changed the electrochemical properties. Example 4. Alkali resistant glass fibres Fibres of conventional glass, so called E glass, are not resistant to alkalis. The resistance of so called alkali resistant glass fibres which contain a few per cent zirconium (Zr0 2 ) is also relatively poor. These fibres cannot be used as (structural) reinforcement in concrete or mor¬ tars containing cement or Ca(0H) 2 or similar. Polystyrene is resistant to alkalis. Treatment of glass fibres with a compound in accordance with the invention, containing the two components polystyrene dissolved in at least an alkylalkoxysilane with the addition of a third component, a (silanol)/polymerisation/condensation catalyst (metallic acid ester) rendered conventional E glass fibres alkali resistant. Treatment procedure is as follows. It is applied in two stages, each stage in the form of two alternatives (in this example). Priming, Stage l,Alt I 3% by weight zirconium acid ester (zirconium- tetrapropylate) in styrene (monomeric) Alt II 3% by weight zirconium acid ester (zirconium- tetrapropylate) in monomeric isobutyltrimeth¬ oxysilane Coating, Stage 2,Alt A 3% by weight polystyrene in propyltrimethoxy¬ silane Alt B 6% by weight polystyrene in propyltrimethoxy- silane The effect of the treatment was compared with the mode of action of untreated glass fibres of two commercial types, E gl ass AR glass with about 7% Zr0 2 content The tested glass fibres were strands of fibres of ca 1 mm 2 total area. Treatment of the strands/yarns was accomplished by drawing the fibres through a bath and thereafter drying the fibres by quenching (and at room temperature). Stage 2 followed immediately after Stage 1. The materials used were styrene of industrial quality polystyrene in expanded/extruded form as waste material , density ca 40 kg/m 3 . Zirconium acid esters and alkyltrialkoxysilanes by Huls, Troisdorf, FRG. The test procedure was as follows: 1. Glass fibres were treated in two stages for comparison of the effect of Zr0 2 (Alt I) and the effect of a combination of Zr0 2 and alkylsilanes (Alt II) as primers, the effect of a change of the surface of the fibre by Zr0 2 and the catalytic effect of Zr0 2 in the catalyst/polystyrene/silane system, and the effect of different concentrations of polystyrene in the coating. 2. The treated fibres were dried at room temperature. 3. The dried samples were placed in a concentrated solution of NaOH at a constant temperature of 50 * C ("etching") for different periods of time, (0), 1, 4, 16 and 64 hours. 4. After "etching" the yarns of glass fibres were washed to remove residues of NaOH before drying. 5. The washed fibres were dried at room temperature. 6. Tensile strength in relation to intensity of "etching" (time) was determined by drawing loops of yarn. Alkali resistance as a function of the type of treatment is set out in Table 6. Table 6. Tensile strength (kgf/mm 2 ) as a function of alkali impact ("etching time"). Type of fibre/treatment AR E Stage 1 Stage 1+2 none I II IA IB IIA IIB Time of etching, hours 0 37.3 41.2 1 20.6 25.8 43.2 46.4 4 15.9 14.9 17.7 32.0 30.9 32.0 35.1 32.5 16 14.5 15.5 10.3 16.5 33.0 36.1 64 15.9 13.4 16.5 26.8 23.7 27.8 Conclusions: The difference between untreated fibres of E glass and AR glass is negligible. The deposition of Zr0 2 on the glass fibres is not enough (Treatment I). A coating of silane containing polystyrene is effective even in small quantities. Exampl e 5 The previous Example No 4 gave details of a two stage treatment which improves the alkali resistance of conventional E glass fibres. These two treatment stages were carried out immediately one after the other. This example gives details of the treatment effect when a catalyst such as Zirconium propylate dissolved 1n a solvent was allowed Lu hydrυl,yi>e and to condense on the glass surface before stage 2 of the treatment was applied. The solvent for the catalyst was allowed to evaporate. A solution of 3% by weight of zirconium propylate in white spirits was used as primer. Polystyrene in alkyl alkoxysilane, with the concentrations of silane being 3% and 12% by weight respectively of the components of the solution, as in Example No 4, was used as the coating. The large Increase 1n ultimate strength due to the solution containing 12% polystyrene, which is surprising, may be due to the fact that the treatment has also strengthened the glass fibre yarn in a physical/- echanical manner. The surface of failure in this sample was markedly even, 1n contrast to the surfaces of failure in other samples, for instance those in accordance with Example No 4, which exhibited a filamentous uneven surface. Failure in this example occurred instantaneously, in contrast to failure of the samples 1n accordance with Example No 4, both treated and untreated ones, which occurred gradually and slowly. The results of a two stage treatment of the glass surface, using a fully reacted catalyst with the solvent evuμuraled, are sel uul in Table 7. Table 7. Alkali resistance of different glass fibres Primer Coating Tensile strength 3% oy weigni or % Dy weight or poly¬ cone. Naun, birc, zirconium propylate styrene in alkyl 64 hours in white spirits alkoxysilane kgf/mm 2 0 % 15.0 3% 37.1 12% 53.0 o primer 12% 21.7 Example 6. Compatibility between the treatment preparation in accordance with the invention and hardened water based mortar. 6a. One end of a glass fibre strand of 1 mm 2 cross sectional area was cast into portland cement mortar with a water/cement ratio of 0.35 to a depth of 5 mm. The strand had been surface treated in accordance with the invention by Treatment Type IIB according to Table 6. The glass fibre yarn was subjected to a tensile test in a conventional tensile testing apparatus. The ultimate load on the yarn was 35 kgf. The yarn did not become detached from the mortar. 6b. Surfaces of cement mortar and concrete were coated to a thickness of 1 mm: with a composition comprising 25% by weight of polystyrene dissolved fn isobutyltrimethoxysilane. (The alkalinity of the surface was deter¬ mined by phenolphthalein, pH > 9). It was found impossible to remove the hardened mass from the surface with a chisel or hammer without destroying the underlying cement or concrete layer. The same effect was achieved on concrete or mortar which had already undergone carbonation if the surface, prior to treatment with the polystyrene/silane solution, was primed with a solution containing a polymerisation catalyst in accordance with the invention, e.g. 1% by weight of titanium ethylate in an organic solvent such as white spirits or similar.

Claims: PATENT CLAIMS 1. Agent for the treatment of surfaces or surface layers, charac¬ terised by the fact that it contains as components a) polystyrol dissolved in at least one component b), an alkoxysilane of the general formula R' n -Si-R^. n , where R' is a C1-C20 hydrocarbyl or halogenated hydrocarbyl group, R is a C1-C6 alkoxy group or/and Si-R 4 ", where R" is a C1-C6 alkoxy group. 2. Agent for the treatment of surfaces or surface layers in accord¬ ance with the previous Claim No 1, characterised by the fact that the alkoxysilane occurs as a monomer, di er, trimer or oligomer, as a partial hydrolysis product/hydrolysis product or/and as a condensation product. 3. Agent for the treatment of surfaces or surface layers in accord¬ ance with the previous claims, characterised by the fact that it contains as additive a component c), a (silanol) polymerisation/ condensation catalyst. 4. Agent for the treatment of surfaces or surface layers in accord¬ ance with one or more of the previous claims, characterised by the fact that it is a solution which is possibly processed into solutions, emulsions, suspensions, dispersions or aerosols. 5. Procedure for the treatment of surfaces or surface layers, characterised by the fact that these surfaces or surface layers are treated with an agent in accordance with the previous claims Nos 1-4, if necessary in different layers in different treatment phases/treatment stages. 6. Procedure for the treatment of surfaces or surface layers, characterised by the fact that surfaces or surface layers are treated in successive treatment stages with a preparation which together comprises the components a), b) and c) in accordance with one or more of the previous claims and claim No 3, but with the limitation that component a) polystyrol and component c) (silanol) polymerisation/condensation catalyst do not occur in the same partial preparation.

Inventors: MAKES FRANTISEK, PUEHRINGER JOSEF, MAKES, FRANTISEK, PUEHRINGER, JOSEF
Applicants: MAKES FRANTISEK, PUEHRINGER JOSEF, MAKES, FRANTISEK, PUEHRINGER, JOSEF
Application year: 1989
Main classification: C09D3
IPC codes: C03C25, C04B41, C08L83, C09D125, C09D183