NL8100026A - METHOD FOR FORMING CASTING CORE AND FORMING USING BINDERS THAT CAN BE CURED BY POLYMERIZATION WITH FREE RADI-CALMS. - Google Patents

Description

* Jt, s' N.0. 29,763 *. -1- "-L.

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Process for molding cores and molds using binder cans which can be cured by free radical polymerization, y

The invention relates to a method of forming casting cores and molds using binders that can be cured by free-radical polymerization.

In casting core and mold forming processes, binder materials of many different types are used. After curing, the bonding material must impart the core and shapes various desirable S properties. Examples of such properties are erosion resistance, moisture resistance and disintegration or shaking. Also, in the formation of cores or shapes, large production is a desirable goal.

According to modern coring or molding techniques, the use of unsaturated drying oils derived from natural products as the binder material has begun. Linseed oil is the first example of a drying oil. Flaxseed oil and other unsaturated oils undergo oxidation-initiated polymerizations upon exposure to air, resulting in the formation of solid, highly cross-linked structures. Polymerization can be accelerated by applying heat or using chemical methods. These bonding materials are known in the industry as "core oils". In forming a core, the oil is mixed with sand and the sand mixture is formed into a core or mold. Curing is carried out by heating or by leave core or mold in place for a long period of time. Core-oil binders may contain other components in addition to the oil component »such as oil-derived esters» unsaturated hydrocarbon resins and solvents. molds such as molds and cores have been known for 50-60 years.

Processes that are faster than the above nuclear oil using processes were introduced for 25-30 years of lapping.

In these processes, the binder must be cured using heat. These "hot box" methods are based on resin compositions that cure by heat. These thermosetting resins include phenol-formaldehyde, urea-formaldehyde and furfuryl alcohol-formaldehyde resins. In addition to the use of heat to cure or polymerize these 8100026 Λ, * ^ • * "-2 binders, acids are often included as catalysts.

About 10 years ago, feasible processes for the production of casting cores and molds were introduced at high room temperature. The binder formed by these methods is based on urethane chemistry. The binder mainly consists of two liquid resin components. One component is a phenol-formaldehyde resin * The other component is a polymeric isocyanate. The phenolic and isocyanate resins are mixed with sand and can be used in both a “cold box” and a “no bake” 10 system. According to the "cold box" system, the sand coated with the two components is blown into a core box. When the sand is blown into a core bin, a gaseous tertiary amine is passed through the core bin, instantly curing or solidifying the material to form the binder. For example, U.S. Pat. No. 3,159,579 describes this technique. In forming "no bake" type cores, the polyisocyanate component, the phenolic resin component, and a catalyst are all mixed with sand simultaneously. The sand mixture is then poured into a core tank or model. The sand mixture remains fluid for a period of 20 years. After this period has elapsed, curing or polymerization is initiated by the catalyst and the core is rapidly formed when the binder components react rapidly to form a urethane binder. PNo bake binders are known from U.S. Pat. No. 3,676,392.

A further binder composition and method for forming a cast binder is described in U.S. Pat. No. 3,879 * 339 * Ifc. this patent discloses a "cold box" method, ie, a room temperature processable process using curing gas to form a casting binder, comprising an organic resin, which can be cured by acid, and an oxidizing agent. This binder component is cured with sulfur dioxide gas. The combination of sulfur dioxide and the oxidizing agent leads to the formation of sulfuric acid, the acid of which cures the organic resin, which can be cured by acid. Sulfuric acid is mainly formed in situ and the acid reacts with the resin. Thus, the curing of the binder composition is accomplished.

None of the above-described cast binders have such utility and versatility that it can be considered as a general or irreplaceable cast binder.

8100026 * é "±" -3-

Therefore, the object of the invention is to provide a new binder * based on chemistry not previously used in foundries or other fields of application of binders. In particular, the object of the invention is to provide a binder of the "cold box" type * which cures quickly. A further object is to provide a "cold box" binder * which can be used in casting of aluminum and other light metals.

The invention relates preferably to room temperature curing binders * which are formed by mixing 10 Ca) of a binder composition or material * containing ethylenically unsaturated monomers * ethylenically unsaturated polymers and mixtures of such unsaturated monomers, ethylenically unsaturated polymers and mixtures of such unsaturated monomers and polymers * and (b) a free radical-forming initiator * comprising a peroxide and 13 a catalytic agent. The invention generally relates to binder compositions * which can be cured at room temperature * which can be polymerized by free radical initiation and chain extension. These binder compositions serve to adhere materials and especially particulate solid materials. In particular, the invention relates to compositions capable of bonding sand or other aggregates to form metal casting molds or cores, such as, in particular, aluminum and other light metals.

Shapes and cores formed using these binders show improved disintegration ability when used in casting light metals, i.e. metals cast at low casting temperatures. Curing of the binder material to form the binder composition preferably takes place at ambient temperature and is accomplished by a free radical initiator * comprising a peroxide and a catalytic agent. In a preferred embodiment, the catalytic agent is gaseous and curing or solidifying is almost instantaneous. However, the different possibilities for curing mode and speed depend on the choice of different catalytic agents.

The invention relates to a casting binder * in which the chemistry differs from the chemistry previously used in foundries to form binders. The binder can also be used as a binder or binder component in areas other than foundries. The chemistry on which this binder is based * _ · _ - * 8100026 • · · ·. ·. · * · -K- Λ. - is highly analogous to the chemistry used hitherto in coatings (see, e.g., British Patent 1,055,242) and adhesives. An anaerobically cured cast binder based on similar chemistry is described in Canadian Patent No. 5 1,053.HO. Curing of this binder is very slow and requires the application of heat to effect curing. According to the present invention, an anaerobic curing method is not employed and is rapidly * almost instantaneously * cured at room temperature using certain catalytic agents.

It is known that molds * ie cores and molds * are formed by depositing a binding material or chemical onto sand or other aggregate material, shaping the sand into the desired shape and curing the binding material or the chemical to take place or cause to form a binder. According to the invention, the binder can be obtained by joining two parts. Part I is a binder or composition that undergoes polymerization and cross-linking, wherein bonding * retention or bonding takes place in the desired form of the sand or other aggregate. The second part (part II) is an agent that causes the polymerization and cross-linking of part I. This agent is referred to as the "free radical initiator". The term "cross-linking" as used herein refers to a chain structure obtained when a polymer is coupled with another polymer or with a monomer. The term "polymerization" includes "cross-linking" but also refers to chain extension with monomers only.

Part I of the binder system can be described as an unsaturated composition * which can be cross-linked or polymerized by a free-radical mechanism. The unsaturation t * is preferably located at the end of the chain or in the side chain. Still, internal saturation is acceptable and polymerization will occur upon association with Part II. Depending on the method of preparation of the component of part I, it is also possible to have a component of part I with unsaturation at the end of the chain and / or in the side chain and also internal unsaturation in the same component. The polymerization mechanism is believed to be almost entirely of the free-radical type * when cross-linking compositions (i.e., one or more unsaturated polo-polymers) are involved. When certain monomers such as the 810002 • ί »-5- * binding composition« are used, it is possible that part of the polymerization may take place by a mechanism other than the free radical mechanism. This description is believed to reflect the polymerization mechanism 5 and that the "free radical mechanism" is used for convenience and accurately describes such a mechanism in almost all cases. However, it should be noted that in addition to the free -radical mechanism under certain conditions other mechanisms of polymerization may also occur. Curing is carried out using Part II - a free-radical initiator comprising a peroxide and a catalytic agent. It has been found that unsaturated reactive monomers, polymers and mixtures thereof (ie the binder composition) can be used as a binding material, which can be cured instantaneously after the use of certain catalytic agents as a free-radical initiator. The unsaturated monomers and Polymers are preferably ethylenically unsaturated. [0101] Beactive polymers, which may also be described as oligomers or as adducts *, which preferably contain vinyl or acrylic unsaturation, are used, for example, as binding compositions which form a binder for casting cores or molds upon polymerization. from sand · The free radical forming initiator (part II) is mixed with the reactive polymer or monomer (part I) and forms free radicals which polymerize the binding composition to form the binder · This combination of a peroxide and a catalytic agent, which can be chemical in nature, but also in the form v An energy may be present in this description is referred to as "free radical initiator"

The free radical-forming initiator used in accordance with the invention can be used in a number of ways to cause polymerization of Part I materials. For example, the peroxide can be mixed with the Part I material and this mixture can be uniformly poured onto sand. After sand is shaped into the desired shape, it can be exposed to the catalytic agent. Alternatively, the catalytic agent can be added to the material of Part I and this mixture can be used for sand coating and the coated sand can then be · shaped into the desired form · The peroxide component of the free radical-forming initiator can be are then added to the molded article and curing by polymerization takes place. It is also possible to divide the material of part I into two portions.

The catalytic agent can be added to one portion and the peroxide can be added to the second portion. After having applied at least one portion to the material to be bonded, polymerization takes place when the two portions are combined. Depending on the type of the catalytic agent or the equipment used and application, the latter method may not be practicable. However, if the binding material is used to adhere non-particulate materials together, the latter method may be particularly suitable. The choice of the various catalytic agents has a major impact on the agents that can be used to polymerize the binder material and on the rate at which the binder material is cured.

The choice of the suitable catalytic agent makes it possible, for example, to allow the binding material to polymerize immediately at room temperature or to delay the polymerization for some time and finally to allow it to take place at elevated temperature. The availability of options for the conditions under which the binding composition polymerizes is considered to be of significant significance.

As described above, the binder of Part I is a polymerizable unsaturated monomer, polymer, or mixture of one or more such monomers and / or one or more such polymers. Examples of materials which are suitable monomeric compounds for the component of Part I include a wide variety of monofunctional, difunctional, trifunctional and tetrafunctional acrylates. Representative examples of these monomers are alkyl acrylates, hydroxyalkyl acrylates, alkoxyalkyl acrylates, alkyl methacrylates, hydroxyalkyl methacrylates, 30 alkoxyalkyl methacrylates, cyanoalkyl methacrylates, N-alkoxymethyl acrylamides and N-alkoxymethyl methacrylamides. Differential monomeric acrylates are, for example, hexanediol diacrylate and tetraethylene glycol diacrylate. Other acrylates that can be used are trimethylolpropane triacrylate, methacrylic acid and 2-ethylhexylmetha-35-crylate. Polyfunctional acrylates are preferably used when the monomer is the only binding material in the binder system. As mentioned above, no cross-linking should take place when only monomers are used as the binding material. In addition to a free-radical mechanism, polymerization kO can also be initiated by another mechanism.

8105025 -7- * · *

Examples of unsaturated reactive polymers which have been found to be particularly suitable for forming this casting binder * are epoxy acrylate reaction products * polyester / urethane / acrylate reaction products * polyether acrylates and polyester acrylates. For example, unsaturated polymers used in the composition of Part I include commercially available materials * such as TJVITHANE 782 and 783 »acrylated urethano olomers from Thiokol and CMD 1700 * an acrylated ester of an acrylic polymer and CELEAD 3701» an acrylated epoxy resin * both available from Celanese.

Active polymers can be formed in a number of ways.

In a preferred process for preparing the reactive polymers, prepolymers having isocyanate group groups are formed by reacting polyhydroxy compounds or polyols with a diisocyanate. The prepolymer is further reacted with a hydroxy-13 alkyl acrylate to form an oligomer. A second possibility * which has been found to be advantageous * is to convert a polyisocyanate compound *, preferably a diisocyanate compound, with a hydroxyalkyl acrylate. The reaction product is an "adduct" of these two materials. In addition, oligomers and adducts can be prepared simultaneously under suitable conditions.

In addition to the reactive unsaturated polymer, a solvent * preferably of a reactive nature * can be included and preferably included as a component of the binding material. Depending on the nature of the unsaturated binding material, inert solvents can also be used. Preferably, a solvent is used which is an unsaturated monomeric compound * as described above with the monomeric materials of Part I. Accordingly, the material of Part I may comprise a mixture of those unsaturated monomers and unsaturated polymer presented above. with regard to the use as materials of Part I as such. Best results are obtained when a solution of an unsaturated reactive monomer and a monomer unsaturated solvent is used. This combination appears to be more capable of copolymerization and crosslinking to form a binder matrix * required for adhering sand or other aggregates * to form the casting core or mold or to bond other materials.

As already mentioned, preferably in part I of the binder system, an unsaturated monomer compound is used as the solvent in addition to the unsaturated polymer. As described above »

___J

8100026 * ': \ y' * '' -8- ... : vΛ - -j-: "-.; :. r .. -, '': '’: - -; These monomers have an unsaturated character and can be cross-linked with the polymer and additionally serve as a solvent for the unsaturated polymer. Any of the unsaturated monomers (or combination thereof) which have been reported to be used as materials for part I as such * can also be used as solvents »The ethylenic unsaturation is preferably of the vinyl or acrylic type. Examples of monomers that are preferably used as solvents for the unsaturated polymers are pentaerythritol triacrylate * trimethylolpropane triacrylate * 1,6-hexanediol diacrylate and tetraethylene glycol diacrylate * The amount of monomer in Part I may be 0-100% by weight based on total weight. of the binding composition of Part I.

It is possible to use the reactive polymer as the material of Part I and the free-radical initiator without any solvent * including unsaturated monomer * present for the unsaturated polymer · It is also suitable to use the unsaturated monomer as the Part I material with a free-radical forming initiator but without using the reactive polymer to obtain a polymerized binder »Neither of the two combinations described above is preferred» As previously mentioned, the preferred binder system includes Part I * which a reactive unsaturated polymer * dissolved in a reactive solvent * preferably containing a monomeric unsaturated solvent * and part II, which contains a free radical-forming initiator.

The free radical-forming initiator comprises two components.

The first component is preferably an organic peroxide. Any substance * which can be used as the first component * that forms free radicals upon exposure to a catalytic agent could be used with the free radical polymer polymerizable Part I * binding material such as unsaturated polymers * monomers and mixtures thereof described above. ven. The amount of peroxide can vary over a wide range and depends to some extent on the catalytic agent used. »

Generally, however, it can be stated that 0 * 5 - 2 wt% peroxide * 35 based on the weight of the binder material (Part I) will form a satisfactory binder system under most conditions. Examples of preferred peroxides are tert. butyl hydroperoxide * cumene hydroperoxide and methyl ethyl ketone peroxide. It is worth noting that hydroperoxides are more preferred than peroxides. Using peroxide non-consistent curing -8100026 * '* -9- * »« taken into account * Mixtures of peroxides and hydroperoxides and mixtures of hydroperoxides may be used ·

The component of the free radical-forming initiator that forms the catalytic agent is preferably chemical in nature, preferably sulfur dioxide in gaseous form. Other chemical catalytic agents, which are believed to be of some practical use, are amines and NO3. It should be noted again that a change in the catalytic agent may have a large impact on the polymerization rate. other non-chemical agents which act on the peroxide component of the free radical-forming initiator are used · For example, heat can act on peroxide at a suitable minimum temperature of 60 ° C to form free radicals, which for the polymerization of the materials of Part I * An increase in temperature leads to an increase in polymerization and causes faster curing * The polymerization takes place without the presence of a chemical catalytic agent *

In practice, in the foundry, the unsaturated reactive polymer, monomer or mixtures thereof and the peroxide-component of the free radical-forming initiator are preferably mixed with sand in the usual manner. The sand mixture is then brought into a desired casting mold by stamping, blowing or by other known methods of forming casting cores and molds. The formed article is then exposed to the component of the free-radical-forming initiator which forms the catalytic agent. According to the process of the invention, gaseous SQ- is preferably used as the catalytic agent of the free radical-forming initiator. This gas is only present in the aforementioned catalytic amounts. The time during which the sand mixture 30 is exposed to the gas can be as little as 0.5 seconds or less, and the binder component cures on contact with the catalytic agent. In a process using a "cold box" SO 2 used in foundries, when the catalytic agent is used, it is suspended in known manner in a stream of carrier gas. The carrier gas is usually N 2. An amount of only 0.5 wt. # SO4, based on the weight of the carrier gas, is sufficient to cause polymerization. * It is also suitable to contact SO2 with the binder component without the presence of any carrier gas. Part I contain further ingredients. There may be -__ a 8100026. -10- · Λ, for example wetting and foaming additives are used. Silanes have been found to be particularly useful additives. Particular preference is given to using unsaturated silanes, eg vinyl silanes.

As a cast binder, this binder composition has the following advantages. The ability of the binder to disintegrate is excellent when used in aluminum casting. It has been found that this binder easily disintegrates or shakes out of an aluminum casting using a minimum amount of external energy. The binder also provides good strength properties. The service life of sand mixed with Part I is long. The surface finish of castings made using the binder and the process of the invention has been found to be very good. The production speed of cores and shapes. » formed using this binder system »is fast» especially when SC 2 gas is used as the catalytic agent.

In a foundry using the binder composition of the invention, Part I and a component of the free-radical initiator, preferably the peroxide, will be mixed in known manner with sand or other aggregate suitable for casting processes. The sand mixture is then brought into the desired shape (cores or shapes) in a known manner. Subsequently, the sand mixture is exposed to the second component of the free-radical-forming initiator, preferably the catalytic agent, preferably sulfur dioxide gas, and polymerization of the binder material of Part I immediately takes place to form the binder of the invention.

. The following examples further illustrate the invention. Example I.

Gel tests were performed using various unsaturated monomers and polymers to determine their tendency to polymerization and the polymerization rate. In carrying out the tests, about 1 5-2 g of unsaturated mono-35 mer or polymer (i.e. part I) was mixed with 0 03 g of tert-butyl hydroperoxide (the peroxide component of the free radical-forming initiator ). This mixture was then exposed to SO2 gas (the catalytic agent of the free-radical initiator) by dispersing (bubbling) the gas in the liquid or bQ by forming an SC2 atmosphere above the liquid (contact). The 8100026 Λ * * * r -11- results shown below indicate that all unsaturated monomers and polymers polymerize. Thus, all listed compounds can be used as a binder. The compounds that polymerize or gel quickly are the main cast binders which can be used in high speed casting methods using a cold box and in core forming.

3) part I. Polymerization of acrylic acid quickly, in contact with SO 2 10 ethyl acrylate slowly, in contact with SO 2 n-butyl acrylate slowly, in contact * with SO 2 isobutyl acrylate slowly, in contact with SO 2 2-ethylhexyl acrylate quickly, in contact with SO 2 isodecyl acrylate , in contact with SO 2 2 -ethoxyethyl acrylate quickly, in contact with SO 2 ethoxyethoxyethyl acrylate quickly, in contact with SO 2 20 butoxyethyl acrylate quickly, in contact with SO 2 hydroxyethyl acrylate quickly, in contact with SO 2 hydroxypropyl acrylate quickly, in contact with SO 2 glycidyl acrylate, in contact with SO 2 dimethylaminoethyl acrylate · fast, in contact with SO 2, cyanoethyl acrylate fast, in contact with SO 2 diacetone acrylamide in methanol, 50 wt.% Fast, in contact with SO 2 acrylamide in methanol, 50 wt. # Fast, in contact with SO 2 (K-methylcarbamoyloxy) ethyl acrylate quickly, on contact with SO 2 methyl cellosolve acrylate quickly, on contact with SO 2 50 phenoxyethyl acrylate quickly, on contact ng with SO 2 benzyl acrylate quickly, in contact with SO 2 ethylene glycol acrylate phthalate fast, in contact with SO 2 melamine acrylate quickly, in contact with SO 2 diethylene glycol diacrylate quickly, in contact with SO 2 35 hexanediol diacrylate quickly, in contact with SO 2 butanediol diacrylate quickly, in contact with SO 2 triethyl ethyl glycol contact with SO 2 tetraethylene glycol diacrylate quickly, 'in contact with SO 2 neopentyl glycol diacrylate quickly, in contact with SO 2 40 1,3-butylene glycol diacrylate quickly, in contact with SO 2 trimethylolpropane triacrylate quickly, in contact with SO 2 8100026 ψ * * ·' ·. · · * ''. ..... '·· «· -". ..... ·' '' ....... ^ ·: Ί: ·· * ·. · '', /, -12- · pentaerythritol triacrylate fast * in contact with SO 2 methacrylic acid fast »in contact with SO 2 • methyl methacrylate slow * in bubbling * with SOg 5 2-ethylhexyl methacrylate · slow * in bubbling with SO ^ hydroxypropyl methacrylate fast * in contact with SO 2 glycidyl methacrylate in rapid * in contact with SO ^ dimethylaminoethyl methacrylate fast * on contact with SO2 10 ethylene glycol dimethacrylate quickly * on contact with SO2 trimetbylol propane trimethacrylate quickly * on contact with SO2 glycerol-derived acrylate quickly * on contact with SO-urethane * 65 wt.% in MIAK / HiSol-10 N-methylol water * 60 wt. # fast * in contact with SO2 15 N ~ [isobutyoxymethyl] -acrylamide in fast * in contact with SO2 methanol * 50 wt.

Epocryl R-12 resin (Shell) acrylated slowly * on contact with epoxy resin * 80 wt. # In acetone SO 2 UVITHANE. 783 (Thiokol / Chem.DivK) fast * at: contact with S02 20 acrylated hour than oligomer AROPOL 7200 (ASHLAND) unsaturated poly-slow * at contact with ester resin ^ niacetone * 60 wt.% SO ^ RICON 157 (Colorado Specialty Chemical) slow * in contact with an unsaturated hydrocarbon resin in SO 2 acetone, 50% * # hydroxy PBG-2000 (Hystl Co.) an slow, in contact with saturated hydrocarbon resin in acetone * SO-50 wt%

Example 11.

An unsaturated polymer was prepared by reacting the equivalent amount of 1 mole of pentanediol and the equivalent amount of 1 mole of hydroxyethyl acrylate with the equivalent amount of 3 * 0 moles of toluene diisocyanate. For catalyzing the I. ·. - 1 - (Conversion, dibutyltin dilaurate was used. Based on the solids content, 0.1% by weight of the catalyst was used. Hydroquinone monoethyl ether was used as an inhibitor. The reaction was carried out in an ethylhexyl acrylate and hydroxyethyl acrylate. reaction medium (solvents) When carrying out the reaction, a mixture of TDI and solvent was placed in a reaction vessel.

Pent0 To this mixture, pentanediol was added * and hydroxyethyl acrylate was added * After the addition of hydroxyethyl acrylate was completed, catalyst was added * The reaction was carried out with air blowing · The reaction was carried out for 2 * 1 hours at a temperature of kO -% 5 ° C and then the temperature AecTzs ..- I '-13- * 1 * was raised to 80 - 85 ° C and the reaction was continued for 4.3 hours, then 0.03 wt. Inhibitor was added and the reaction was continued for half an hour. The product was allowed to cool. The product was tested for non-volatile components and a value of 39.2% by weight was found. This corresponds to a theoretical amount of non-volatile components of 60% by weight. The viscosity of the product was 6.0 stokes. Then 20 g of the unsaturated polymer was mixed with 1.6 g of acrylic acid, 10.7 g of diethylene glycol diacrylate, 9.9 g of trimethylolpropane trimeth-10 acrylate and 2.0 g of vinyl silane. Acrylic acid, diethylene glycol diacrylate and trimethylolpropane triacrylate are unsaturated monomers. This solution of unsaturated polymer and unsaturated monomers is designated as Part I. To the solution of unsaturated polymer and unsaturated monomers, 1 g of t-butyl hydroperoxide * the peraxide-15 component of the free radical-forming initiator was added.

Vedron 5010 sand (washed and dried silica sand in the form of fine grains * AFSGrFN 66) was placed in a suitable mixer. Part I and the peroxide component of the free-radical-forming initiator were mixed with the sand until an even distribution was obtained. The amount of part I plus peroxide is 2% by weight, based on the weight of the sand.

The sand mixture was blown into a conventional core cavity or box to produce test cores in the form of standard briquettes to determine the tensile strength known as "dog bones". The "dog bone" test cores were cured by exposing the cores to the catalytic component of the free radical-forming initiator. The catalytic component is gaseous sulfur dioxide. The cores were exposed to the SO 2 catalyst for about 0.5 seconds (gas time) and the catalyst was removed by purging with nitrogen for 15 seconds and the core was removed from the box. The tensile strength of the core was 15.61 kg / cm immediately after removal from the box, 14.35 kg / cm after 3 hours and 15.89 kg / cm after 24 hours.

The same "dog bone" cores as above were used for shaking tests with aluminum castings. 7 briquettes ("dog bones") were molded. A gate system was included in the form. The mold is intended for the production of hollow castings with a layer of metal with a thickness of about 0.6 cm on all sides. At one end of the casting is an opening for removing the core from the casting. casting blocks of aluminum 8f00026 »---. µl of molten aluminum obtained at a temperature of about 704 ° C was poured into the mold. After cooling for about one hour, the aluminum castings were broken from the gate system and removed from the mold for shaking tests.

Shake tests were performed by placing a casting in a container with a volume of about 4.5 liters. The container is allowed to tumble for 5 minutes using an appropriate device. The weight of the sand-containing core, which is removed from the casting in this way, is compared to the initial weight of the sand-containing core, and a percent shake-out is calculated. The sand remaining in the casting after the above-described movement is removed by scraping and also weighed. The sand-containing core bonded with the binder described above was found to have a shake of 100 # 15. It should be noted that the shake test described above is not a standard test. No standard test is known for measuring this property. »It is noted that the test used serves to gain insight into the binder disintegration ability and to compare the relative disintegration ability of a binder. binders. The percentages given are subject to a certain amount of deviation, but are a reliable indication.

Example III

sand Wedron 5010 at 23 - 26 ° C

25 part I.

a) unsaturated monomer acrylic acid 1.6 g, diethylene glycol diacrylate 10 * 7 g * trimethylolpropane trimethacrylate 9 * 9 g 30 b) unsaturated polymer prepared as follows, 20 g preparation of unsaturated polymer i) pblyisocyanate, in mol TDI 4 equivalent 35 ii) polyol, in mole equivalent of glycerol, 1 iii) acrylate, in mole equivalent of hydroxyethyl acrylate, 5 iv) catalyst dibutyltin dilaurate, 0.14 wt% v) inhibitor hydroquinone monomethyl ether 40 vii) solvent, wt # ethylhexyl acrylate and hydroxyethyl acrylate, 40 wt. # viii) temp / time ° C / hour 40 - 45 ° C for 2.13 hours, then 80 - 85 ° C for 81 0 002 6 d * Mnr. no. • 8 r -15- (continued example III)

Example III

ix) viscosity, stokes 16.0 x) non-volatile constituents 5 found 65% by weight # theoretical 60.0% by weight c) additive in grams of vinyl silane - 2.0

Free radical-forming initiator (part II) 10 a) peroxide component 2.2 wt.% Tert-butyl hydroperoxide b) catalytic component SOg gas gas time, sec. 0.5 flushing time, sec. 15 just N 2 y tensile strength, kg / cm immediately after unboxing 12.46 3 hours 15.19 24 hours 16.31 amount of binder (part I + 2 wt. # 20 peroxide component) used in casting metal aluminum shake, weight 100.

Example IV V

sand Wedron 5010 Wedron 5010

25 part I.

a) unsaturated monomer acrylic acid 1.6 g, di-hydroxyethyl acrylate ethylene glycol diacryl-2.2 g, dicyclopentate 10.7 g, trimethylacrylate 20.8 g, ylolpropanetria cry- (N-methylcarbamoyloxy) -30 late 9 * 9 g of ethyl acrylate 17.3 gb) unsaturated polymer prepared as follows, 20 g preparation of unsaturated polymer 35 i) polyisocyanate, TDI, 3 in mole equivalent ii) polyol, in mole Olin 20-265 &, 1 equivalent of polyoxypropylene glycol Iii) acrylate, in hydroxyethyl acrylate, 4 mole equivalent iv) catalyst dibutyltin dilaurate, 0.14 wt% v) inhibitor hydroquinone monomethyl ether 8100023 ------- - 16- '. . * '' ♦ V ".. ··. - - · '..' /" "./. ·;" - ·. ·.

(continued examples IV and V).

Example IV V: vii) solvent ethylhexyl acrylate and by weight # hydroxyethyl acrylate, 40% by weight # viii) temp / time 40-45 ° C for

° C / hours 2.1 hours, then 80 - 85 ° C

, during 4.75 € hours 1 x) viscosity 4.2 10 x) non-volatile constituents found 59.2 wt. # theoretical 60.0 wt. # c) additive in g vinyl silane 2.0 g 15 free radical forming initiator ( part II) a) peroxide component 11.3 wt. # cumene-2.4 odor. # tert.butyl hydroperoxide · hydroperoxide b) catalytic compo-S0-gas S0_-gas 20 nent gas time, sec * 0.5 1 purge time , sec. 15 soot N? Carbon black N_ tensile strength, kg / cm immediately after taking out of the box 11.20 25 hours 3 1.75 24 hours 48 hours 16.24 amount of binder 2 wt% 2 wt & 30 (part I + peroxide component) aluminum used in casting: metal shakeout%. 100.

Example ^ VII

sand Wedron 5010 Wedron 5010

part I.

a) unsaturated monomeric pentaerythritol triacrylic acid 7.2 g of dicrylate 40 g of ethylene glycol diacrylate 40, 21.4 g, trimethyl yol propane triacrylate, 13 gb) preparation of unsaturated polymer 1 8100026 i) polyol cyanate continued examples VI and VII).

♦ 5m -17- rt

Example VI VII

ii) polyol, in mole equivalent 5 iii) acrylate, in mole equivalent iv) catalyst v) inhibitor vii) solvent in 10% by weight # viii) temp / time ° C / hours ix) viscosity x) non-volatile constituents found) theoretical c) additive in g free radical forming initiator (part II) a) peroxide component 2.4 wt. S tert.bu- 2, ½ wt. tert.butyl- * tyl hydroperoxide hydroperoxide - b) catalytic compo - SO ^ gas S0 ~ gas nent 25 gas time, sec. 0.5 1 flushing time, sec. 15 10 2 tensile strength, kg / cm immediately after taking out of the box 3.36 9 * 10 30 3 hours 2½ hours amount of binder 2 wt. # 2 wt. # (Part I + peroxide component) 1 2 3 4 5 6 7 8 9 10 11 8100026 he casting 2. Metal 3 shake, wt. #.

4

Example VIII IX

5 sand Wedron 5010 Port Crescent 6

part I.

7 a) unsaturated monomer acrylic acid 3 * 2 g, diethyl ethylene glycol diacrylic 9, 21.4 g, trimethylic propylene trimethacrylate 19 * 8 g (continued examples VIII and IX) *

Example VIII IX

-18-

V * V

Λ b) unsaturated polymer in the same way as prepared above »40 g of picture IV * 4-0 g 5 i) polyisocyanate TDI * 3 in mole equivalent ii) polyol * in mole Olin 20-265 »1 equivalent 10 iii) acrylate, in hydroxyethyl acryl molar equivalent, let» 4 iv) catalyst dibutyltin dilaurate »0.14% by weight, v) inhibitor hydroquinone monoethyl ether» 0%, 07% by weight vii) solvent in pentoxone (93 »7) hywt. # Droxyethyl acrylate, 35 wt. $ Viii) temp./time 4.0 - 45 ° C for 2

20 ° C / hours hours »then 20 - 85 C

for 4 hours (ix) viscosity. thixotropic after 3 days x) non-volatile constituents 25 found 63 »1 wt # theoretical 65 wt # c) additive in g vinyl silane vinyl silane A-172 2.0 g acrylic acid 1 * 6 g 30 free radical forming initiator ( part II) a) peroxide component (90 wt. $ 6) tert.butyl peracetate tyl hydroperoxide - (6 g) 2.2 wt., # 35 b) catalytic compoSO2 "gas heat 4-50 ° C for 90 seconds .

gas time »sec. 0.5 flushing time, sec. 15 just N-2 ^ tensile strength, kg / cm 4-0 immediately after taking out of the box 3.71 5 * 25 3 hours 6.51 24-hours cold strength 10.85 11.20 4-5 quantity binder 2 wt.% wt. 2 wt.% (part I + peroxide component) 8100026 *>% (continued examples VIII and IX).

Example VIII IX

-19- Λ metal casting 5 shake * weight # *

Example X XI

sand Wedron 5010 Wedron 5010

part I.

a) unsaturated monomer acrylic acid 1.6 g, tri-same as in previous

10 methylol propane tri-image X

acrylate 9 * 9 gb) unsaturated polymer prepared in the following manner * 20 g preparation of unsaturated polymer i) polyisocyanate, in TDI * 3 * 5 mole equivalent ii) polyol, in mole glycerol / diethylene equivalent glycol mixture (1: t) * 1 20 iii) acrylate, in hydroxyethylacrymol equivalent late ή- (iv) catalyst dibutyltin dilaurate 0.1½ wt.% v. inhibitor hydroquinone monomethyl-25 * ether 0.07 wt.% vii) solvent in ethylhexyl acrylate + wt. hydroxythylacrylate (4-6) k0 wt. # viii) temp./time kO - 45 C for

30 ° C / hours 2 hours then 80 - 85 C

for 4- * 8 hours ix) viscosity 10 stokes x) non-volatile components 35 found 59 * 9 wt.% theoretical 60 * 0 wt.% c) additive in gram vinyl silane A-172 * 2 HiSol 10 10 * 7 kO free free radical initiator (part II) a) peroxide component 70 wt. S tert. butyl hydroperoxide 2.2 wt. # b) catalytic compound gas 1/2 gas SO2 gas in N2-k5 nent carrier gas gas time, sec. 0 * 5 1/2 flush time * sec. 15 with N2 ~ gas no 8100025

__ I

-20- (continued examples X and XI)

Example X XI

p "tensile strength, kg / cm immediately after bet from the box 15.96 4.90 5 take 5 hours 15.89 8 * 54 24 hours 17.99 15.61 amount of binder 2 wt. # 1.5 wt. part I + * peroxide compo-10 nent) when casting used aluminum metal shake, wt. $ - 100.

Example XII XIII

15 m »n <È p * Wedron 5010 Wedron 5010

part I.

a) unsaturated monomer acrylic acid 1.6 g, the same as in pre-ethylene glycol 5.49 g, image XII trimethylolpropane triacrylate 9.9 g b) unsaturated polymer prepared in the following manner, 20 g preparation of unsaturated polymer 25 i) polyisocyanate, 4 "mole equivalent ii) polyol, in mole · glycerol, 1 n equivalent iii) acrylate» in hydroxyethyl acrylate »» 30 mole equivalent iv) catalyst dibutyltin dilaurate «0.14 wt # v) inhibitor hydro c non-monomethylether ether 0.03 wt.%, vii) solvent in methyl isoamyl ketone, wt. # HiSol 10 (6505) // // Γ · 35 wt. # - -. ! Viii) temp./time 40 - 45 ° C for "° C / hours 1.75 hours, then 80 - 40 85 ° C for 4.5 hours ix) viscosity, 10" stokes x) non-volatile "45 constituents found 64.1 wt.%, theoretically 65 wt.% "8100026 iOLC" -21- (continued examples XII and XIII).

Example XII XIII

c) additive in g vinyl silane 2.0, f *

HiSol 10 5.3 5 free radical forming initiator (part II) a) peroxide component 2 * 2 wt. # Tert.butyl- hydroperoxide - 70 b) catalytic component 1 # SO2 gas in N2 SO2 gas 10 n carrier gas gas time, sec. 20 0.5 flushing time, sec. no 15 with air 2 tensile strength, kg / cm immediately after taking out of the box 15.26 12.39 15 hours 3.99 10.65 6.65 24 hours 16.31 10.50 amount of binder 1.5 wt. # 1, 5 wt. # (Part I + peroxide component) in casting aluminum aluminum metal shake used, wt Si 100 .100.

/ ____j 8100026

Claims (21)

2. Process according to claim 1, characterized in that sand is used as aggregate. 3. Process according to claim 1 or 2, characterized in that a binder material is used, in which the monomer is mixed with at least one other ethylenically unsaturated monomer. Process according to one or more of the preceding claims, characterized in that a catalytic agent of a chemical nature is used. 5. Process according to claim 4, characterized in that gaseous sulfur dioxide is used as the catalytic agent * 6. Process according to one or more of the preceding claims, characterized in that a binder material is used which contains, in addition to the monomer, at least one ethylenically unsaturated polymer. 7. Process according to one or more of the preceding claims, characterized in that the catalytic agent is suspended in a carrier gas and exposed to the binding material for at least 0.5 seconds, Process according to one or more of the preceding claims, characterized in that an elevated temperature of at least about 52 ° C is used as the catalytic agent. 9. Method according to one or more of the preceding claims, characterized in that the binding material is used in an amount of up to 10% by weight, based on the weight of the sand. 10. Method for forming castings, characterized in that 1. a binding amount of a binder-CO material is distributed on a casting unit, the binder material containing an ethylenically unsaturated polymer 8100026 • -23-, 2. the aggregate into the shape of the desired casting and 3. polymerize the binding material using a free carbon steel forming initiator comprising an organic peroxide and a catalytic agent · Process according to claim 10, characterized in that the aggregate used is sand. 12. Process according to claim 10 or 11, characterized in that a binder composition is used, which comprises an ogan 10 in which an ethylenically unsaturated monomer is mixed with at least one other ethylenically unsaturated polymer. Process according to claims 10-12, characterized in that a catalytic agent of a chemical nature is used. Process according to Claims 10 to 13, characterized in that the catalytic agent used is sulfur dioxide. 15. Process according to claim 10 - 1 * f, characterized in that an elevated temperature of at least about 52 ° C is used as the catalytic agent. 16. Process according to claims 10-15, characterized in that an oligomer is used as unsaturated polymer. 17. Process according to claims 10-16, characterized in that an adduct is used as unsaturated polymer. 18. Method for bonding at least two materials, characterized in that a) a binding amount of a binder material is distributed on at least one of these materials, said binder material containing an ethylenically unsaturated monomer * b) the contacting materials to be bonded and c) polymerizing the binding material using a free carbon steel-forming initiator comprising an organic peroxide and a catalytic agent. A process according to claim 18, characterized in that the binder material used is a material comprising a mixture in which the monomer is mixed with at least one other ethylenically unsaturated monomer. Process according to claim 18 or 19, characterized in that a catalytic agent of a chemical nature is used. kQ 21. Process according to Claims 18 to 20, characterized in that gaseous sulfur dioxide is used as the catalytic agent. 44. Process according to claims 1.8 - 21, characterized in that the binder material used is a material which contains, in addition to the monomer, at least one ethylenically unsaturated polymer. . 23 * Process according to claims 18-22, characterized in that the catalytic agent is suspended in a carrier gas and exposed to the binder material for at least 0.5 seconds. 2k, Process according to claims 18-23, characterized in that an elevated temperature of at least about 52 ° C is used as the catalytic agent. 25 · Method for bonding at least two materials »15. The characteristic is that 1. a binding amount of a binder material is distributed on at least one of these materials, the binder material containing an ethylenically unsaturated polymer» 2. the to be bonded contacts materials and 3. polymerizes the binding material using a free carbon steel-forming initiator, which surrounds an organic peroxide and a catalytic agent. A method according to claim 25, characterized in that a binder composition is used which contains a 25 mixture in which an ethylenically unsaturated monomer is added. mixed with at least one other ethylenically unsaturated polymer · 2? «Process according to claim 25 or 26» characterized in that an M & lyMSck agent is used which is of a chemical nature. 28. Method as claimed in claims 25 - 27, characterized in that! | me, that. gaseous sulfur dioxide is used as the catalytic agent. 14. A process according to claims 25-28, characterized in that an elevated temperature of at least about 52 ° C is used as the catalytic agent. 30. A process according to claims 25-29, characterized in that an oligomer is used as the unsaturated polymer. 31. Process according to claims 25-30, characterized in that an adduct is used as unsaturated polymer. 40L 32. Method for casting light metal objects, 81 0 0 0 2 ff * '*. -25- A in which these metal objects are formed with the use of castings »which disintegrate after the metal objects have been cast» characterized in that a) a casting is formed in the manner described in claim 1, 5b) a light metal is heated until it melts and can be cast, c) cast the light metal using the molded casting »d) solidify the cast metal, and e) disintegrate the cast and disintegrate the cast from the cast object of light metal. 33. A method of casting light metal objects, wherein said metal objects are formed using castings which disintegrate after the metal objects are cast, characterized in that a) are described in claim 3. cast, b) a light metal is heated to melt and can be cast, c) the light metal casts using the molded casting, d) the cast metal solidifies, and e) the cast disintegrates and removing the disintegrated casting from the cast light metal object. 20 3k. Method for casting light metal objects, these metal objects being formed using castings which disintegrate after the metal objects are cast, characterized in that a) a casting is described in the manner described in claim 6 b) a light metal is heated to melt and can be cast, c) the light metal casts using the molded casting, d) the cast metal solidifies, and e) the cast disintegrates and it expands removes fallen castings from the light metal casting. 35. Method for casting light metal objects, these metal objects being formed by using castings which disintegrate after the metal objects have been cast, characterized in that a) are described in claim 10 a casting, 35 b) a light metal is heated to melt and can be cast, c) the light metal is poured using the molded casting, d) the cast metal is solidified, and e) the casting is disintegrated and removing the disintegrated casting from the cast light metal object. JfO 36. Method for casting light metal objects, 8100026 ^ * · -26- JE Λ j. Wherein these metal objects are formed using castings which, after casting the metal objects, disassemble with the characteristic that a) a casting is formed in the manner described in claim 12, 5 b) a light metal is heated to melt and can be cast, c) the light metal is cast using the molded casting, d) the cast metal is allowed to solidify and e) disintegrating the casting and removing the disintegrated casting from the light metal casting, 8100026