CH629232A5 - Emulsion - Google Patents

Description

The present invention relates to emulsions based on a mixture of water and an unsaturated

3,629,232

Polyester resin and at least one unsaturated monomer are removed and by an amine in the course of a condensation poly-containing mixture. merization reaction can be cured. However, epoxy

Concrete made with Portland cement has been very expensive in resins for many years, so an economic advantage has been used by those of the construction industry. Its application in the use of a cheaper cross-linkable system obtained by the industry is based on its high compressive strength. However s de. Unsaturated polyester resins, which with an unsaturated one show very low tensile strength and bending stiffness and un-monomers are crosslinkable, are also subject to acidic attacks for some time. Furthermore, the tendency to use glass fiber-reinforced polyester resins towards the small gaps in the concrete also tends to be used.

tion, if it is subject to the conditions of freezing and thawing. However, copolymerizable mixtures are composed of one. io unsaturated polyester and an unsaturated monomer

Efforts have been made to improve these properties, usually not used as aqueous emulsions. Nevertheless, in order to thereby expand the area of application, US Pat. No. 3,256,219 describes water-in-resin emulsions, various resins incorporated into the concrete in various ways, in which the aqueous phase was even worked during and after the Addi are. For example, Emulsions Thermoplastic polymerization of the unsaturated polyester with the unsheared polymer remains dispersed in the concrete while mixing 15 saturated polymers. On the other hand, or if the concrete has a structure when it sets, there is no suggestion that the porosity described in the U.S. Patent has sufficient porosity, the set concrete is with the emulsions after the addition of the binder, by hy-thermoplastic polymers been impregnated. This graduation sets, remain stable.

conditions have the properties of the concrete in normal conditions. IT-PS 585 721 describes polyester resins that have a hy-

Ambient temperature improved. However, if he did contain extreme 20 drastic cement filler. Such fillers are exposed to temperatures e.g. a flame temperature, polyester resins melt upon formation of a dry medium, which consequently leads to a decrease in the unsaturated polyester, an unsaturated Mo strength. For this reason, such materials have not found any other application in the construction industry which tests free radical initiators and promoters. UIUj made of a non-ionic emulsifier. Water will

Concrete masses with an incorporated thermosetting 25 finally mixed into the dry mix. The water resin would be given better properties than with hydrogenated cement. The heat of hydration accelerates that of a thermoplastic resin because a thermosetting resin does not melt addition polymerization between the unsaturated monomers. Various attempts have been made to ren and the unsaturated polyester which is initiated by the initiator for thermosetting resins or, more specifically, cross-linked resins. The emulsifier favors the dispersion of the clay masses. The Australian patent 30 water and therefore the cement within the mixture. These

426 171 relates to a dry cement containing invention shows the night that the mixture has been prepared in situ with a hydraulic cement, a multivalent. Furthermore, the fact that an addition ion is redispersible in water does not carry the Rech metal salt, that, in order to obtain good properties of the mixture in the case of lysis, which is to be achieved by a / ß-monoethylenically unsaturated setting, it is essential to use an emulsion of What -

Contains carboxylic acid monomers derived units, a 35 ser> unsaturated polyester and unsaturated monomer to form complexing agents and a trimethylolalkane. The addition of form that remains stable after the addition of the cement.

Water to dry mix leads to hydration of the ad- Accordingly, the present invention provides an emulsified

addition polymers and for complex binding of the polyvalent ion on the basis of a mixture of water and an inadequate metal ion, whereby a condensation reaction between saturated polyester resin and at least one unsaturated mono-mixture of the addition polymer and the trimethylolalkane containing 40 mer, characterized in that occurs simultaneously with the hydration of the cement. that the stability of the emulsion through the proportions of unsaturated

US Pat. No. 3,437,619 deals with a dry middle monomer in the mixture, through the ratio of the Schung, which an unsaturated polyester resin, monomeric styrene, reactants, which in the manufacture of the unsaturated Po-Portland cement, a base activated , Resin dispersible Iyesters were used, and by the molecular weight of the initiator and an effective amount of an inhibitor. 45 of the reactants used in this way is influenced, so that when the water is added, the emulsion activated by the cement is so stable that demixing or deworming hydroxyl ions introduce the catalyst, which is then a yeast, by the addition of a hydration-setting addition polymerization between the unsaturated polyester binder does not occur.

and initiates the styrene. Although prima facie polyester resin.

Dry mixtures have an advantage over emulsions for producing a product from a hardenable one, since they reduce the transport costs, this advantage is made up of a mixture of one of these emulsions and one which is often offset by the cost of the dry masses, such as hydration-binding Binder is characterized in that it is the case with the mass, which is in the Australian patent, that an addition polymerization between an un-

No. 426,171, and by the problem of saturated polyesters and an unsaturated monomer from avoiding setting during transportation and running the 55, the hardenable mixture is hardened, thereby causing storage, resulting in premature setting and consequently product , the amount of which leads to a loss with the binding. The use of an inhibitor, which must be sufficient according to the mixed emulsion in order to prevent premature setting in the presence of US Pat. No. 3,437,610, by the amount of water provided by the emulsion, which is also disadvantageous because it prevents the occurrence of To let hydration run.

Addition polymerization in all cases, except in the case of ideal 60- It should be recognized that among the above understandings, can prevent and often delay. Such terms “demixing” or “demulsification” in part would be given to a system which understood a cement, filling meaning in the usual sense the splitting of an emulsion, substances and an emulsion which by mixing water usually two separate ones liquid layers, an aqueous layer with a crosslinkable monomer and a crosslinkable layer and an organic layer are formed. Thus, medium has ceased to exist, with the water for hardening the 65 generally ultimately passing the emulsion when cement is provided by the emulsion. Such a binder also absorbs water from the emulsion and system is disclosed in US Pat. No. 3,310,511, which has an epoxy binder sufficient. The emulsion breaks je-resin emulsion describes that incorporated into a concrete mix but at no stage in two separate liquid layers,

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after the binder has been added. The emulsion preferably contains 35 to 65% by weight of water and is a water-in-resin emulsion. The binder can be hydraulic cement, (burnt) gypsum or a mixture of lime and hydraulic cement. 5 is preferably the binder Portland cement.

The stability of the emulsion in the presence of a binder is influenced by the proportion of the unsaturated monomer in the mixture, by the ratio of the reactants used in the preparation of the unsaturated polyester, and by the molecular weight of the reactants used.

It has been found that emulsions based on unsaturated polyester / monomer mixtures which contain, for example, more than 30% by weight of unsaturated monomers - based on 1S by weight of the mixture - are unstable. The mixture of the unsaturated polyester and the unsaturated monomer therefore preferably contains not more than 30% by weight of the unsaturated monomer, based on the weight of the mixture. 20th

The molar ratio of the unsaturated to the saturated constituents is preferably in the range from 0.8 to 1.75, the range from 1.35 to 1.4 being particularly preferred.

Preferably the polyhydric alcohols and the polyhydric carboxylic acids used in the preparation of the emulsions according to the present invention have a high molecular weight, i.e. in the range of 100 to 1000; and particularly preferred are not polymers such as polyester polyols. 30th

Suitable polyols are ethylene glycol, trimethylpentanediol and neopentyl glycol. A polyethylene glycol can also be used.

The total amount of the alcohol components mentioned is preferably used in an excess of 2 to 5 mol% - 35 based on the stoichiometrically required amount. The preferred molecular weight of the unsaturated polyester is in the range of 3,100 to 3,600.

When the polyester mentioned is formed, the condensation polymerization preferably proceeds until the polyester has an acid number of 25 or less.

Preferably, the unsaturated polyester or monomer contains substituted atoms of bromine or chlorine to improve the fire resistance of the finished products after mixing the emulsion with binders, cement, baked gypsum, lime, aggregates, etc. Thus, the t-trabromophthalic anhydride is preferably used as one of the reactants used in the preparation of the unsaturated polyester that is incorporated into the emulsions according to the present invention. The im-saturated monomer can be a vinyl monomer, i.e. styrene, methyl methacrylate, diallyl phthalate monomer, triallyl cyanurate monomer or mixtures thereof.

The reaction course of the addition polymerization is preferably initiated by a free radical initiator. The addition polymerization can be carried out by a method of hot or cold polymerization. It is possible to produce a resin with two initiator additives, one additive allowing the partial polymerization to proceed at ambient temperature, while a second catalyst additive completes the complete and final polymerization in a hot pressure system. This process, which is influenced by the two additives, makes it possible to convert a mortar into pre-gelled rolls. A suitable initiator for initiating a reaction at low temperatures is the dibenzoyl peroxide supported by a copper compound.

However, the preferred initiators are methyl ethyl ketone peroxide and butyl perbenzoate. Other suitable initiators are organic hydroperoxides and hydrogen peroxide. It is also possible to use free radical initiators that are activated by UV light. Alternatively, the method for carrying out the addition polymerization can be initiated by irradiation with high radiation energy. When the binder and initiator are added to and mixed with the emulsion, the binder usually penetrates the emulsion and is hydrated by the water. If the initiator used is of the type that is heat activated, the heat released during the hydration of the cement usually activates the initiator after 10 to 15 minutes. The active initiator then typically initiates the addition polymerization between the unsaturated polyester and the unsaturated monomer. The heat of hydration usually favors the rate of addition polymerization which leads to rapid setting of the mixture of the emulsion and the binder. The initial setting usually occurs within 30 minutes. However, when a low temperature initiator is added to the emulsion and aggregate mixture, the mixture typically does not begin to bind until several hours have passed. Therefore, in practice, the binder is preferably added at the point of use. On the other hand, in the event that the place of use is not very far from the mixing plant, the initiator can be fed into the mixing plant and the binder can be mixed in at the place of use.

Of course, any suitable form of reinforcement can be incorporated into the final product before it sets, such as fiberglass or steel. Short length glass fibers that are incorporated into the material during manufacture are usually quite satisfactory. The formation of the emulsion of the unsaturated polyester and the unsaturated monomer is important for the production of a satisfactory material. The emulsion can be prepared by mixing the unsaturated polyester, the unsaturated monomer and the water in a high speed stirrer capable of converting the dispersed phase into a particle shape with a particle size that is 25 microns or slightly less. The unsaturated polyester resin is preferably such that it can be emulsified with up to 60% by weight of water without de-emulsification occurring when the binder is added. For example, to form stable emulsions, it is possible to use small amounts of an emulsifier, e.g. a non-ionic or anionic emulsifier, but this is not necessary. To ensure the stability of the emulsion during transportation and storage, it may be necessary to add a stabilizer such as titanium dioxide (rutile) and an emulsion of a vinyl or acrylic addition polymer (1% by weight of the unsaturated polyester plus unsaturated monomers). The filler can be calcium carbonate or calcium silicate.

The invention is further explained in more detail with reference to the following examples.

Example 1 From the following ingredients

Weight unit 269

65

Ethylene glycol tetrabromophthalic anhydride (molecular weight: 463.7) 382

Maleic anhydride or fumaric acid 224 Phthalic anhydride 149

an unsaturated polyester with a high molecular weight acid unit is produced.

A mixture of the constituents mentioned is heated in a reaction vessel with continuous stirring

5

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an inert gas stream is passed through and over the batch. The heating cycle is carried out as follows:

a) initially at a temperature of 170 ° C. for 1 h,

b) then at a temperature of 185 ° C for 30 minutes

and c) finally at a temperature of 190 ° C. for 7 hours. The implementation of the individual components is then complete,

when the acid index is below 20 and the polymer obtained has cooled.

Example 2

Example 1 is repeated, but the following constituents are used to prepare the polyester:

Trimethylpentanediol (molecular weight: 146.15) pentaerythritol maleic anhydride

Parts by weight

467 15 98

20th

The polyester obtained thus contains glycol units of a glycol of high molecular weight.

Example 3 25

Example 1 is repeated, but the following constituents are used to prepare the polyester:

Parts by weight 394

30th

Trimethylpentadiol (molecular weight: 146.15)

Tetrabromophthalic anhydride (molecular weight: 463.7) 430

Pentaerythritol 41

Maleic anhydride or fumaric acid 186

The polyester obtained contains units of a glycol and an acid each having a high molecular weight.

Example 4 40

Example 1 was repeated, but starting from the following components:

Parts by weight of trimethylpentanediol 394

Tetrabromophthalic anhydride 430

Pentaerythritol 41

Maleic anhydride or fumaric acid 186 2,2-bis (methylally ether) -1-butanol 8

Again, the substituted butanol is fed towards the end of the esterification reaction.

Example 7

The polyesters of Examples 1 to 6 are each mixed with 290 parts by weight, 200 parts by weight, 280 parts by weight, 290 parts by weight, 200 parts by weight and 280 parts by weight of monomer in the form of styrene, respectively, to obtain a mixture of the unsaturated polyester and the unsaturated monomer.

Example 8

The polyesters of Examples 1 to 6 are each mixed with 290 parts by weight, 200 parts by weight, 280 parts by weight, 290 parts by weight, 200 parts by weight and 280 parts by weight of the monomer in the form of the methyl methacrylate, respectively, to obtain a mixture of the unsaturated polyester and the unsaturated monomer.

Example 9

The polyesters of Examples 1 to 6 are each mixed with 290 parts by weight, 200 parts by weight, 280 parts by weight, 290 parts by weight, 200 parts by weight and 280 parts by weight of the monomer in the form of a 50/50 mixture (by weight) of the styrene and the methyl methacrylate to give a To obtain mixture of the unsaturated polyester and the unsaturated monomer.

Example 10

The polyesters of Examples 1 to 6 are each mixed with 710 parts by weight, 490 parts by weight, 690 parts by weight, 710 parts by weight, 490 parts by weight and 690 parts by weight of the diallyl phthalate monomer, respectively, to obtain a mixture of the unsaturated polyester and the unsaturated monomer which crosslink at high temperature can be.

Parts by weight

Ethylene glycol

250

Tetrabromophthalic anhydride

382

Maleic anhydride or fumaric acid

224

Phthalic anhydride

149

2,2-bis (methyl allyl ether) -l-butanol

19th

45

The substituted butanol is added at the end of the esterification reaction.

Example 11

The polyesters of Examples 1 to 6 were each mixed with 710 parts by weight, 490 parts by weight, 690 parts by weight, 710 parts by weight, 490 parts by weight and 690 parts by weight of a 50/50 molar mixture of the styrene and the triallyl cyanate monomer to produce a mixture of the unsaturated 50 Obtain polyester and the unsaturated monomer according to the invention.

Example 5

Example 1 is repeated, but the following 55 components are assumed:

Parts by weight of trimethylpentanediol 467

Pentaerythritol 15

Maleic anhydride 98

2,2-bis (methyl allyl ether) -l-butanol 10

Again the substituted butanol is added towards the end of the esterification reaction.

60

65

Example 6

Example 1 is repeated, but starting from the following components:

Example 12

The mixtures of Examples 7 to 11 are converted into emulsions, the following recipe being selected: 500 parts by weight of mixture

3 parts by weight of promoter in the form of cobalt octoate, 300 parts by weight of water.

Mixing or emulsification is carried out using a high-speed mixer. The mixing speed must be so high that practically the entire disperse phase is converted into particles with a particle size of 25 microns or less.

Example 13

Products containing cement are made by mixing the following ingredients in a conventional cement mixer:

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6

Parts by weight

Emulsion of Example 12

803

Portland cement

500

Silica flour

5

sand

3,300

pebble

2,700

Methyl ethyl ketone peroxide

(Catalyst)

5

The mixture obtained is poured into molds between two layers of a glass fiber mat and placed under a pressure of 2.5 kg / cm 2 until hardening occurs. This gives plates with very high mechanical strength and good anti-corrosion properties.

Example 14

The mixtures of Examples 8 and 9 are converted into emulsions, starting from the following recipe:

Parts by weight of resin 500

Water 300

Mixing is carried out by means of a high-speed stirrer, the mixing speed being such that practically all of the resin is converted into particles with a particle size of 25 microns or less.

Example 15

Cementitious products are made by mixing the following ingredients in a conventional cement mixer:

Parts by weight of the emulsion of Example 14,800

Portland cement 500

tert-butyl perbenzoate (catalyst) 10

Sand 3,300

Pebble 2,700

The mixtures are poured into molds between two layers of glass fiber mat, placed under a pressure of 4.5 kg / cm2, heated for 5 minutes at 99 ° C and finally removed from the mold. Sheets of very good mechanical properties, good chemical resistance and improved impermeability are obtained. When a welding torch flame acts on the surface of a plate produced in this way for 30 minutes, the plate surface only blackens; igniting or even burning the plate is not detectable.

Example 16

The mixtures of Examples 7 to 9 were converted into emulsions by mixing the following components:

Parts by weight of mixture 500

Promoter in the form of cobalt octoate 3

Water 500

Mixing was carried out using a high-speed stirrer, the mixing speed being so high that practically the entire disperse phase is converted into particles with a particle size of 25 microns or less.

Example 17

Gypsum materials are made by mixing the following ingredients in a conventional cement mixer:

Parts by weight

Emulsion of Example 16 1003

Plaster of Paris 500

Silicon dioxide flour 5

Sand 3,300

Pebble 2,700

Methyl ethyl ketone peroxide (catalyst) 5

The gypsum mass obtained is poured into molds between two layers of a glass fiber mat and subjected to a pressure of 3 kg / cm 2. The boards obtained have similar mechanical properties in terms of strength to those made from cement, but they are far stronger than conventional gypsum boards.

Example IS

The mixtures of Examples 7 and 9 are converted into aqueous emulsions by mixing the following constituents:

Parts by weight of mixture 500

Water 500

Mixing takes place with the aid of a high-speed stirrer at such a high mixing speed that practically the entire disperse phase is converted into particles with a particle size of 25 microns or less.

Example 19

Gypsum masses are produced by mixing the following components in a conventional cement mixer:

Parts by weight of emulsion of Example 18 1000

burnt plaster 500

tert-butyl perbenzoate (catalyst) 10

Sand 3,300

Pebble 2,700

The mixtures or compositions obtained are poured into molds between two layers of glass fiber mat and subjected to a pressure of 3 kg / cm 2. The plates obtained in this way show similar mechanical strength properties as plates made from cement; however, they are far stronger than conventional gypsum boards.

Example 20

Cementitious products are made by mixing the following ingredients in a conventional cement mixer:

Parts by weight

Emulsion of Example 14,800

Lime 500

Silicon dioxide flour 5

Sand 3,300

Kiesel 2 700 methyl ethyl ketone peroxide

(Catalyst) 5

The mixtures are poured into molds between two layers of a glass fiber mat and subjected to a pressure of 2.5 kg / cm 2 until hardening occurs. The plates obtained in this way show very high mechanical strength and good anti-corrosion properties.

Example 21

Cement-containing products are made by mixing the following ingredients in a conventional cement mixer:

5

10th

15

20th

25th

30th

35

40

45

50

55

60

65

7,629,232

Parts by weight concrete resin / invention

Emulsion of Example 14,800 sand according to

50/50 mixture (parts by weight) of product lime or Portland cement 500

Silica flour 5 5 Specific weight 2.4 2.1 1.9

- Sand 3300 compressive strength, kg / cm2 300 1200 1780

Kiesel 2700 flexural strength, kg / cm2 70 1300 1300

Methyl ethyl ketone peroxide (catalyst) 5 tensile strength, kg / cm2 30 430 500

Impact resistance, kg / cm2 0.4 10 8.2

io exothermic maximum 30/40 ° C 120 ° C 75/80 ° C

The masses or mixtures obtained are poured into molds between two layers of a glass fiber mat and a die using the three polyesters of Examples 1 to

Exposed to pressure of 2.5 kg / cm2 until the hardening of the end products obtained is almost completely waterproof. The plates obtained in this way show very good mechanical properties. This property is essential for the production of building boards and good anti-corrosion properties. 15 and the like. materials used essential. It

The products according to the invention can very easily be found that the polyesters of Example 3 are compared and are superior to the conventional concrete in terms of temperatures in the range from -600 to + 135 ° C. and in relation to the strength properties. E.g. the test results obtained with repeated thermal shocks within the specified product according to Example 13 are insensitive in the above temperature range. Furthermore, the following table can be used to design those properties of known 20 ° product in such a way that it (only) experiences a slight shrinkage during the Abbin concrete and known resin / sand mixtures of the known dens. Contrast values of type compared. less than 1 mm / m can be easily achieved.

C.

Claims (29)

629 232 PATENT CLAIMS 1. Emulsion based on a mixture of water and a mixture containing an unsaturated polyester resin and at least one unsaturated monomer, characterized in that the stability of the emulsion by the proportions of unsaturated monomers in the mixture, by the ratio of the reactants were used in the production of the unsaturated polyester, and is influenced by the molecular weight of the reactants used in such a way that the emulsion is so stable that segregation by addition of a binder which sets by hydration does not occur. 2. Emulsion according to claim 1, characterized in that it contains 35 to 60 wt .-% water - based on the weight of the emulsion. 15 3. Emulsion according to claim 2, characterized in that it is a water-in-resin emulsion. 4. Emulsion according to claim 3, characterized in that it has as unsaturated polyester resin one which is obtainable by condensation polymerization between a plurality of hydroxyl group-containing compounds and a number of carboxyl group-containing compounds, at least one of the compounds mentioned being unsaturated, while the rest is saturated. 5. Emulsion according to claim 4, characterized in that the molar ratio of the unsaturated compounds to the saturated compounds is in the range from 0.8 to 1.75. 6. Emulsion according to claim 4, characterized in that the molar ratio of the unsaturated compounds to the saturated compounds is in the range of 1.35 to 1.4. 30th 7. Emulsion according to claim 4, characterized in that the compounds containing multiple carboxyl groups have been selected from the groups consisting of tetrabromophthalic anhydride, maleic anhydride, fumaric anhydride and phthalic anhydride. 35 8. Emulsion according to claim 4, characterized in that that the compounds containing several hydroxyl groups have been selected from the group consisting of ethylene glycol, trimethylpentanediol, polyethylene glycol and neopentyl glycol. 4 <> 9. Emulsion according to claim 4, characterized in that the compounds containing several hydroxyl groups were mixed with the compounds containing several carboxyl groups with pentaerythritol before the condensation polymerization and then 2,2-bis- (methylallyl ether) -l-butanol was added towards the end of the condensation polymerization. 10. Emulsion according to claim 4, characterized in that the condensation polymerization was carried out until the polyester thus obtainable had an acid number of not more than 25. 50 11. Emulsion according to claim 4, characterized in that that the compounds having multiple hydroxyl groups are present in an excess of 2 to 5 mol%, based on the stoichiometric requirements. 12. Emulsion according to claim 4, characterized in that at least one of the compounds mentioned has a molecular weight in the range from 100 to 1000. 13. Emulsion according to claim 4, characterized in that the polyester has a molecular weight that is in the range of 3,100 to 3,600. 14. Emulsion according to claim 3, characterized in that that the mixture contains no more than 30% by weight of unsaturated monomer, based on the weight of unsaturated polyester resin and unsaturated monomer. 15. Emulsion according to claim 14, characterized in that 65 the unsaturated monomer is a vinyl monomer or an acrylate or methacrylate monomer or that the unsaturated monomer is composed of styrene, methyl methacrylate, 55 60 Triallyl cyanurate and diallyl phthalate existing group has been selected. 16. Emulsion according to claim 14, characterized in that the mixture contains an addition polymerization promoter as an accelerator for the addition polymerization between the unsaturated polyester and the saturated monomer. 17. Emulsion according to claim 16, characterized in that the promoter is cobalt octoate. 18. Emulsion according to claim 3, characterized in that the mixture contains an initiator which can initiate the addition polymerization between the unsaturated polyester and the unsaturated monomer. 19. Use of the emulsion according to any one of claims 1 to 18 for the manufacture of a product from a curable mixture of one of these emulsions and a binder which binds by hydration, characterized in that an addition polymerization is carried out between an unsaturated polyester and an unsaturated monomer which allows the hardenable mixture to harden, whereby a product is formed, the amount of the emulsion mixed with the binder having to be sufficient to allow the hydration to take place in the presence of the amount of water provided by the emulsion. 20. Use according to claim 19, characterized in that a filler containing silicon dioxide is added to the curable mixture. 21. Use according to claim 19, characterized in that a hydraulic cement or Portland cement or fired gypsum or a mixture of lime and Portland cement is used as the binder. 22. Use according to claim 19, characterized in that the addition polymerization is initiated by an initiator. 23. Use according to claim 22, characterized in that the initiator is added just before mixing with the binder. 24. Use according to claim 22, characterized in that the initiator has been heat-activated in order to initiate the addition polymerization at an elevated temperature. 25. Use according to claim 22, characterized in that an organic hydroperoxide is used as the initiator. 26. Use according to claim 22, characterized in that dibenzoyl peroxide or methyl ethyl ketone peroxide or tert-butyl perbenzoate is used as the initiator. 27. Use according to claim 19, characterized in that the addition polymerization is caused by means of an initiator system which contains two initiators, one of which initiates a partial addition polymerization, while the other, which has been heat-activated, completes the addition polymerization. 28. Use according to claim 20, characterized in that sand, pebble or a silica-containing additive or mixtures thereof are used as the silica-containing filler. 29. Use according to claim 19, characterized in that the unsaturated polyester resin is such as is obtainable by a condensation polymerization between several carboxyl group-containing compounds and several hydroxyl group-containing compounds, at least one of the compounds being unsaturated while the rest is saturated.