DD283597A5 - COMPOSITE MATERIAL WITH ALKALICALLY RESPONSIVE MATRIX AND A GLASS COMPONENT, AND USE THEREOF - Google Patents

Abstract

The invention relates to composite materials with an alkaline matrix and a glass component and a method for protecting glass surfaces from alkaline corrosion. In accordance with the present invention, the glass component, prior to incorporation into the matrix, has coated surfaces resulting from the reaction of an unsupported polyester with emollients or from the reaction of a saturated polyester with crosslinkers or from the surface adhesion of cellulose esters. Such coated surfaces are largely alkali stable and adhere to Glasoberflaechen, especially on glass fibers {composite material; Alkalibestaendigkeit; Glass fiber; Glass fiber layer; Esters, macromolecular; Asbestos substitution; alkyd resins; Corrosion, alkaline; Corrosion protection}

Description

-A-

2530/8825 / DD

Composite material with alkaline matrix and a Gisskomponente and its use

Field of application of the invention

The invention relates to a composite material comprising an alkaline matrix which wraps a body of glass. Such a composite material can either be a binding material consisting of glass fiber reinforced building material or a glass container used in the chemical industry or a glass tube.

ChdralcJe r / s FLLC oies bckann-fen SU mdes th e technic

When embedding glass in media that causes alkaline corrosion, there is a risk of corrosive attack on the corresponding glass surfaces. This problem has become particularly clear in the introduction of glass fibers in cements, where it was necessary to substitute the Asbsstfassrn previously used in cements. So z. 8. For composite with a peat or polymeric materials, it has been noted that alkaline corrosion of the glass fiber resulted in significant sacrifices in strength. A number of methods have already been developed for protecting glass fibers in slurries with cement. For example, known from US-PS 4017 322, to give ZrO ₇ containing glass fibers in эіпа aqueous solution of phosphoric acids, 2ігчопзз1гэп, titanium salts or Hafniumsalzen prior to incorporation into the cement, to thereby improve the alkali resistance. It is known from L-1059-116 163 to coat glass fiber with a saccharide-containing resin and apply an epoxy resin over it. A coating of granules with binders granulated glass waste with inorganic or organic binders is claimed in DE-AS 2243 118, in order to obtain an aggregate for concrete and concrete blocks.

In addition, from DE-OS 2556539 a method for protecting glass fibers in an alkaline environment is known in which a precipitate is formed on the glass fibers from a chemically reactive substance, the matrix material and ', Yasser. Another method (DE-OS 2231 905) works with a curable furan resin as a coating material »

To improve the processability of glass fibers is in the

U.S. Patent No. 4,370,157 has proposed a sizing agent containing an unsaturated polyester resin having free carboxy groups. This sizing material is primarily intended to provide advantages in the manufacture, storage and processing of glass fibers and to react with an amino-functional silane to form a solid product. The problem of alkali resistance was not affected by this proposal, nor by other sizing agents containing polyester resins (eg DE 2557073, DE 2528995, DE 2459320, DE 2430616, DE 2429922).

In the known cem-fil fiber, a coating which contains the protective substances is applied to a relatively stable base glass (DE 2432017, 2559056, 2750560). The film former, a phenol-formaldehyde resin or a modified polyvinyl acetate is not identical to the protective substance, a polyhydroxyaromatic compound. A disadvantage of most methods is primarily that relatively expensive products are used for dis enveloping the glass fibers in order to achieve the desired effect. In many cases, adhesion to the glass or matrix is also insufficient.

In British Patent No. 1278777, water-soluble alkyd resins have been used to improve the abrasion for glass reinforced polymers.

Aim of the invention

It is an object of the invention to avoid dis disadvantages of known composite materials in terms of cost and alkali stability.

_ 3 essence of the invention

It is an object of the present invention to develop glass fiber composites in which alkaline corrosion of glass fiber can not be widely practiced for a sufficient period of time and to provide a method for protecting glass surfaces from alkaline corrosion.

According to the invention, the composite consists of an alkaline-reacting matrix and a glass component, the glass component having coated surfaces prior to introduction into the matrix, the reaction of an unsaturated polyester with curing agents or the reaction of a saturated polyester with crosslinking agent or the surface adhesion of cellulose esters arises.

The surfaces of the glass components may be in the form of glass containers, glass filaments or textiles glassware or other glassware. The glass is preferably an oxide glass and can be obtained by melting. It may also have been obtained from slags or natural rocks. It may also have been obtained from alkoxylates or other hydrolyzable starting materials by the sol-gel process. Preferably, Ε-glass or glasses with a higher completeness in the basic medium can be used, for. B. based on the glass system Na ₂ O.

The application of the protective medium is carried out by dipping, spraying, by means of a roller or an impregnated aid or in another suitable manner. As a composite material which is present together with the glass fiber in the composite material according to the invention, an inorganic matrix such as cement or an organic plastic or elastomer product comes into question. For the purposes of the invention, cement means binders which at least temporarily form an alkaline medium. The glassy article provided with the protective coating is generally embedded in the matrix to form a corresponding composite.

In the case of, for example, panels for the construction industry, cut coated fibers are blown into a cement slurry or a viscous polymer and the finished sheet is removed from the mold in a conventional manner after curing. The matrix can also be applied to a glass object and cured without further shaping. In a broader sense, the M3trix can also be an alkaline-reacting liquid in which the glass article coated according to the invention is located. When using a saturated polyester, it is possible to use as crosslinking agents compounds having unsaturated C-C bonds, for example unsaturated fatty acids, acrylic or vinyl compounds, which may be present in the mixture in addition to the actual resin. The alkyd resin may also be chemically modified prior to use by such a crosslinking agent. The glass fiber thereby has a layer of crosslinked saturated polyester which is alkali stable. The applied film former is at the same time protective substance.

While the ester linkages linking the macromolecule of the saturated polyester are alkali unstable, the crosslinking agent provides an alkali-resistant carbon backbone into which the polyester is incorporated. The saponification of the ester bonds then takes place only at the surface of the protective layer. The resulting carboxylate groups cause good adhesion in inorganic matrices, ζ. Cement. The glass fiber can be pretreated, z. 3. by adhesive.

When using an unsaturated polyester, preference is given to using those in which the proportion of multiple bonds is more than 50 mol%, based on the acid residues contained in the polyester. An unsaturated polyester resin according to the invention is preferably crosslinked with styrene.

However, it is also preferable to use aqueous alkyd resin dispersions which have advantageous processing of e.g. Example, fiberglass without the problems of organic solvents vor-r lying coating compositions assure.

A preferred aqueous alkyd resin is z. B. Hydroduxalkyd L 13Ov from VEB Lackkunstharze Zwickau, DDR, which was vinyl-modified based on linseed oil fatty acid.

The polyester layer on a glass fiber or glass fiber bundle has a thickness in the range of 0.1 to 3 microns.

When using a cellulose ester this can be bound by a bonding agent to the glass fiber. It is particularly advantageous to use a cellulose ester in the form of trimethylsilylcellulose.

As the cellulose ester, for example, cellulose acetate or cellulose nitrate may also be used. In the case of cellulose nitrate, a coupling agent is not required because oxidative degradation in the alkaline medium is likely to produce crosslinkable products which form the desired protective layer on the glass surface. When using a coupling agent, an oxide from the group SnO ₂ , TiOp, ZrOp, Cr ₂ O ₃ , Fe ₂ O ₃₁ NiO or CaO is preferred, generated from the metal halides or the organometallic compounds, or it becomes an organofunctional silane or a cationic organofunctional Chromium complex compound preferred.

The invention also relates to a method of protecting glass surfaces from alkaline corrosion. The process is characterized in that a glass surface is treated, prior to introduction into an alkaline medium, with a mixture containing at least one saturated polyester and at least one crosslinking agent and siccatives, or containing a cellulose ester. The crosslinking agent preferably contains unsaturated carbon-carbon bonds. The crosslinking agent is advantageously an unsaturated fatty acid-containing agent.

The cellulose ester is preferably selected from the group consisting of trimethylsilyl cellulose, cellulose acetate and cellulose nitrate.

In the case of cellulose nitrate having a nitrogen content of about 10 to about 12.5 % , no coupling agent is required. For other cellulose esters, adhesion promoters should be used. This can be an oxide from the group SnO ₂ , TiO ₂ , ZrO ₂ , Cr ₃ O ₃ , Fe ₃ O ₃ , NiO, CsO, produced from the metal halides or the organometallic compounds, an organofunctional silane, for example a vinylsilane, methacrylate silane, aminosilane The organic coupling agents may, as is known, be applied to the glass fiber as a primer layer or may be added as a surface-active additive to the intended coating component Cellulose esters by means of an adhesion promoter have surprisingly been found that the cellulose ester can be bound to a glass fiber for a sufficiently long time, for example, without an alkaline attack from the surrounding medium leading to appreciable corrosion of the glass fibers. there the egg The use of cellulose fibers as reinforcing fiber in cements is by no means new, but jeoch so far the cellulose fiber has always been mixed together with the cement slurry and optionally other additives (eg. B, OE-OS 2 850 337, DE-OS 2 718 745). Although there was some improvement in the distribution in the matrix, the problem of alkali corrosion was not affected. Also by the procedure according to the invention occurs on known known enhancement effect on the suspensibility. In addition, however, the alkaline attack is decidedly reduced and for a sufficient period of time.

In general, the effectiveness of the protective layer in the protection of glass surfaces from alkaline corrosion was reflected in E-Glaafasorn deltified with synthetic cementum pore water Ьзі 50 С. As MaS for the Glaszarstörung dients the Мeпгз of silicon, which was dissolved out by the Porsnwasser from the glass fibers, while this amount of unprotected G-rGlas fibers continuously increases to complete glass dissolution, it is barely detectable in accordance with the invention coated glass fibers even after several weeks.

The thickness of the protective layer applied to the fibers depends on the working conditions. The layers used preferably have a thickness of 0.1-3 microns.

exemplary

The invention will be explained in more detail by way of example below.

example 1

On fibers made of Ε-glass, a commercially available regatta finish is applied immediately after its preparation with the aid of a roller, which was diluted with commercial dilution in the ratio 1: 30. Oar commercial varnish contains alkyd resins, soy oil and oil. The fibers used subsequently pass through a sinon shaft through which electric hot air, heated to a maximum of 400 ° C, is passed in countercurrent, and are wound on a drum.

Example 2

A prefabricated fiber bundle made of Ε-glass is drawn by means of deflection rollers by a commercial regattal paint according to Example 1. The dilution ratio is in this case 1: 5. The wetted fiber bundle then passes through an electrically heated to a maximum of 200 ⁰ C tubular Cfan and is wound on a drum.

Example 3

200 g Portland cement PZ 4/45 and 70 g distilled water are mixed by hand. Dam cementbrai are added to 5 g of E glass fibers (fiber length 20 mm, single fiber diameter about 12 microns) and homogenized by hand again. The fiber-cement bladder is placed in molds of 10 mm height and stored for hardening at a temperature around the door. From the glass fiber cement plattan 'obtained in this way prismatic specimens of 10 × 10 × 60 mm are cut out after hardening and decanting.

The flexural strength of the heat-treated samples is 63 % (untreated Ε-glass) and 95 % (treated with saturated polyester) based on dsn -VV, the flexural strength of the 28 d samples stored at room temperature (initial strength) after 56 d of heat treatment.

The long-term behavior in the course of strength of the glass fiber cement composite is significantly better if the E glass fibers used are previously treated with saturated polyester, compared to untreated E glass fibers.

Example 4

Coated and uncoated fibers to the action of synthetic cement pore water at 60 ⁰ C were suspended. The SiO ₂ loss of the uncoated fiber rises almost linearly over the course of 21 days from 0 to about 15 % SiO ₂ (based on the amount present in the glass = 100 %), while from treated fibers only a very small amount (under "1 %) and the test amount is removed in a constant amount.

Example 5

In each case, 5 % of the fiber coated according to Examples 1 and 2 was introduced in a slurry of 13.5 g by the modified Hatshsk's method and the resulting molded body was dried in air, but no decrease in strength occurred over a prolonged period.

Comparative Example 1

To demonstrate the alkali resistance of Examples 1, 2 and 5 coated in accordance with the glass surface, the amount of SiIiciums was determined, which is dissolved out of the coated as well as uncoated Ε-glass fibers by synthetic cement pore water at 60 ⁰ C, in function of OQR exposure time. The SiO 2 dispersion of the uncoated fiber increases almost linearly from O to about 15 % of SiO 2 over the course of 21 days (based on the amount present in the glass = 100; ₀ ), whereas only very small amounts of the fibers treated according to the invention less than 1 %) and constant amount is released over the experimental period.

Example 6

Glass rods made of the alkali-sensitive glass AV 55 were coated with a mixture containing the unsaturated polyester and, indeed, 2% by weight of cyclohexanone peroxide and cobalt naphthanate. Curing took place within 30 minutes. at room temperature. The thus-coated glass rods were then exposed to ETR effect of synthetic cement pore water at 60 ⁰ C.

While uncoated rods of the same glass have a continuous loss of mass, relative to the surface of the rod and the time of action of the pore water, mass loss in the coated rods comes to a standstill after a short time.

Mass loss in mg after weeks

heat treatment

Time in weeks 1 4 8 1

untreated bars 61 64 184 573 treated bars 1218 1238 1249 1352

Example 7

200 g Portland cement PZ 4/45 and 70 g distilled water are mixed by hand. 5 g of E glass fibers (fiber length 20 mm, single fiber diameter about 12 μm) are added to the cement paste and again homogenized by hand. The fiber-cement slurry is placed in molds of 10 mm height and stored wet at room temperature to cure. From the glass fiber cement boards thus obtained prismatic specimens of 10 × 10 × 60 mm are cut out after hardening and demoulding.

The flexural strength of the wärmebehandsltsn samples is after 56 d heat treatment at 60 ⁰ C and humid air S3% (untreated glass) and 103% (treated with unsaturated polyester) based on the value of the bending strength of 28 d stored at room temperature, samples (initial strength).

Example 8

A 3 % solution of trimethylsilylcellulose in tetrahydrofuran, applied to a glasseidsnstrain, and in acid solution (10 g of H-30. + 2Og of Na ₂ GO ₄ /!) Comes 33 to recrystallize the cellulose. When passing the above-mentioned solution through a container glass tube, a cellulose protective layer formed on the inside of the tube after the same treatment.

Example 9

A 3% solution of cellulose triacetate in methylene chloride is mixed with a 5% solution of cyclohexane-ethoxytriethoxysilane and applied according to the invention to a glass fiber strand. Subsequently, the solvent is evaporated, so that, as a result of the treatment, a thin acetate film is formed around the individual filaments of the glass fiber strand.

Seispiel Ip

A 3% solution of cellulose nitrate with a nitrogen content of 10.75 % and a k value of about 48 is dissolved in acetone, mixed with a 5% solution of glycidoxy-repylethoxysilane in acetone and applied to the glass silk such that a film with a layer thickness below 10, to arise. This coating assumes the function set forth in the invention.

Example 11

There were introduced into a cement slurry having a pH value of 13.5 according to the modified Natschek method and dried, the molded body obtained at dsr air 5% each of the example 8 to 10 coated according fiber. Over a longer period no Fostigkoitsabfall occurred.

Comparative Example 2

To demonstrate the alkali resistance of the glass surface coated according to Examples 8-10, the amount of silicon eluted from coated as well as uncoated glass fibers by synthetic peat sponges at 50 ° C, depending on the exposure time, was determined. The loss of the uncoated fiber increases almost linearly from O to about 15 % SiO ₂ over the course of 21 days (based on the amount present in the glass = 100 Jo), whereas only a very small amount (under 1 %) and the test amount is removed in a constant amount.

Example 12

On Ε-glass fibers in their manufacturing process using a graphite roll, an aqueous dispersion of Hydroduxalkyd L130v (Hgrsteller: VE3 Lackkunstharz- and Lackfabrik Zwickau, OOR) ₁ a Vinylmodifiziarten alkyd resin based on linseed oil, carried on by dissolving the mixture of the commercial ir butylglycol Resin (100 ml) with aqueous ammonia solution (4 ml) and water (520 ml). The so coated. Glass fibers are wound, and the coils 2 h at HO ⁰ C in a drying cabinet maintained, wherein the coating dries and cures.

To check the effectiveness of the protective layer 2g are exposed is inventively coated and dried Ξ fiber, the effect of 200 ml of 60 ⁰ C hot synthetic cement pore water containing in 1 1 of water, 8 g NaOH, 42 g KOH and CaO saturated and the amount of of the SiO ₂ contained in the solution. While uncoated Ε glass fibers lose 20 % of the SiO ₂ originally contained in the glass within a treatment time of 16 weeks, the SiO loss of the fibers coated according to the invention is only 5 %.

Claims (25)

2530/8825 / OD claims Composite comprising an alkaline reactive matrix and sinsr glass component, characterized in that the glass component has coated surfaces prior to introduction into the matrix, which consist of the reaction of an unsaturated polyester with curing agents or of the reaction of a saturated polyester with crosslinking agents or of O '. surface adhesion of cellulose esters, 2. Composite material according to claim 1, characterized in that the glass component is in the form of a glass fiber, in particular in the form of a glass strand or a textlien fabric. 3. A composite material according to claim 1 and 2, characterized in that it is the glass fiber to the commercial E-glass fiber or a fiber of higher resistance in the basic medium on the Basi9 of the glass system Na ₂ O-ZrO ₂ -SiO ₂ . 4. A composite material according to claim 1 to 3, characterized in that the glass fiber is pretreated, preferably by applying a size or treatment in saline solutions. 5. Varbundwsrks tof f according to claim 1 to 4, characterized g3! Onnz3ichn that the glass fiber is a fiber of slag or natural rocks. 6. A composite material according to one or more of claims 1 to 5, characterized in that the proportion of Mehrfachbindungan in the unsaturated polyester more than 50 moles ^c a, based on the acid residues contained in the polyester. 7. A composite material according to claim S, characterized in that the polyester resin is crosslinked with styrene. S. Composite material according to claim 1 to 7, characterized in that the saturated or unsaturated polyesters are present in an aqueous dispersion. 9. Composite material according to claim 1 to 8, characterized in that the polyester layer on the glass fiber or the fiber bundle has a thickness in the range of 0.1 to 3 microns. Ю. Composite material according to claim l _t characterized in that the Zelluloseester are bonded via a coupling agent to the glass fiber. 11. A composite material according to claim 1 or 10, characterized in that it is the cellulose ester is trimethylsilyl cellulose. 12. A composite material according to claim 1 or 10, characterized in that the cellulose ester is cellulose acetate. 13. A composite material according to claim 1 or 10, characterized in that the Zalluloseester is cellulose nitrate. 14. A composite material according to claim 10 to 13, characterized in that the adhesion promoter is an oxide from the group SnO ₂₁ TiO ^, ZrO ", Cr _o 0", Fe ₀ O-, NiO, CaO, produced from the metal halides or the organometallic Compounds, or an organofunctional silane or a cationic organofunctional chromium complex compound. 15. A method for protecting glass surfaces from alkaline corrosion, which comprises treating a glass surface with a mixture containing a saturated polyester and at least one crosslinking agent and sikattive before incorporation into an alkaline medium, or with a cellulose ester, optionally together with one Adhesive agent treated. 15. The method according to claim 15, characterized in that the glass is an oxide glass. 17. The method according to claim 15, characterized in that саз glass of slags or natural Gastainen preservation зп been i3t. -4Ψ - 18. The method according to claim 15, characterized in that the glass has been obtained from alkoxylates or other hydrolyzable starting materials by the sol-gel process. 19. The method according to claim 15 to 19, characterized in that the glass is pretreated, preferably with a Haftvsrmittler. 20. The method according to any one of claims 15 to 19, characterized in that it is bsi dar glass surface around the surface of a container, a fiber, a thread or taxtilsn structure is. 21. The method according to claim 20, characterized in that is used as the glass fiber, the commercial Ε-glass fiber or a fiber of higher resistance in the basic medium based on the glass system Na ₂ O-ZrO ₂ -SiO ₂ · 22. The method according to claim 15 to 21, characterized in that the crosslinking agent contains unsaturated carbon-carbon bonds. 23. The method according to claim 15 to 21, characterized in that the crosslinking agent is an unsaturated fatty acid-containing agent. 24. The method of claim 15 to 21 »characterized in that the saturated polyester is a commercial alkyd resin. 25. The method according to claim 15 to 21, characterized in that the cellulose ester is selected from the group consisting of trimethylsilyl cellulose, cellulose acetate and cellulose nitrate. 26. The method according to claim 15, characterized in that the glass surface is treated without the presence of a coupling agent with cellulose nitrate, the nitrogen content is preferably between about 10 and about 12.5 ~ ό. 27. The method according to claim 15, dadurc ^1, characterized in that the adhesion promoter is an oxide from the group SnOp, TiO ₂ , ZrO ₀ , ^ ^г ^ з »Fe ₀ O ,,, NiO, CaO, produced from the metal halides or the organometallic compounds , an organofunctional silane or a cationic organofunctional chromium complex compound.