MXPA00009991A - Curable composition - Google Patents

Abstract

The present invention relates to a curable composition including an acryloxysilane- or acyloxysilane-containing oligomer prepared by a continuous process. In addition, photocurable composition including an alkoxysilane or acyloxysilane oligomer is provided. Methods are provided for curing the curable and photocurable compositions.

Description

CURABLE COMPOSITION The present invention relates to curable compositions. In particular, this invention relates to a curable composition that includes an oligomer containing alkoxysilane and a catalyst, a second curable composition that includes an oligomer containing alkoxysilane and a photocatalyst, and methods for forming cured films. Polymeric materials are widely used as films and coatings to protect and improve the appearance of substrates. To increase the durability, firmness and barrier properties of films and coatings, polymeric materials are often entangled, using a variety of healing chemicals. One such entanglement chemical is the condensation reaction of alkoxysilanes. Polymers with alkoxysilane groups, usually in the presence of a catalyst, are reactive with moisture and can form interlaced polymer films at ambient temperatures. U.S. Patent No. 4,499,150 teaches a method for coating substrates, wherein the coating composition contains an addition interpolymer having alkoxysilane and / or acyloxysilane groups. The crosslinkable interpolymer is formed by the polymerization of alkoxysilane monomers and / or acyloxysilane monomers with other silicon-free monomers. The interpolymer is polymerized in an organic solvent by a batch process, at 119 ° C, and uses initiators and chain transfer agents to achieve the desired molecular weight in the range of 2,000 to 20,000. It is known in the art that processes at high temperatures are effective in producing low molecular weight oligomers from ethylenically unsaturated monomers. At elevated temperatures, depolymerization reactions and chain fragmentation processes compete with the polymerization reactions that increase the length of the polymer chain. For example, U.S. Patent No. 5,710,227 teaches a high temperature polymerization of acrylic monomers, above 150 ° C, by a continuous process, to produce homo-oligomers and co-oligomers of acrylic acid. An advantage of the high temperature process is the ability to remove the chain transfer agents that are often necessary to control the molecular weight of the oligomers produced by the processes at lower temperature. The disadvantages of using chain transfer agents are that they add to the cost of the process, impart unnecessary functionality to the polymer, they can introduce salts into the product, or they need a step of separating the product. Likewise, the commonly used mercaptan chain transfer agents are not only expensive, but also require special handling, since they are extremely odoriferous. A second advantage is that the high temperature polymerization conditions can easily be adapted to a continuous process to obtain high production rates of the oligomers. A curable composition, which incorporates an oligomer containing alkoxysilane groups, in which the oligomer has been produced by an easy and inexpensive process, has been sought for a long time. In the present invention, a curable composition is provided, which includes an alkoxysilane or acyloxysilane oligomer, formed by a continuous reaction process, at 150 to 500 ° C. The continued high temperature reaction process produces alkoxysilane oligomers with polymerization degrees ranging from 2 to 100, preferably without the use of chain transfer agents and with low levels of initiators. In an alternative embodiment of this invention, the alkoxysilane oligomer can be produced by the process at a high temperature, without the use of solvents. A curable composition, which contains an alkoxysilane oligomer and a photoinitiator is also provided, whereby curing is initiated by exposure to actinic radiation. In a first aspect of this invention, a curable composition is provided, which includes: (A) an oligomer, prepared by a continuous process, of one or more monomers selected from the group consisting of ethylenically unsaturated alkoxysilanes and acyloxysilanes and, optionally, one or more other unsaturated monomers ethylenically, where these monomers are polymerized at temperatures of 150 to 500 ° C, in which the oligomer has a degree of polymerization of 2 to 100; and (B) a catalyst.

In a second aspect of the present invention, a method for forming a film is provided, which incorporates a curable composition according to the first aspect. In a third aspect of the present invention, a curable composition is provided, which comprises: (A) an oligomer that includes parts selected from the group consisting of the alkoxysilane and acyloxysilane moieties, wherein the oligomer is prepared by the polymerization of ethylenically unsaturated monomers, wherein the oligomer has a degree of polymerization of 2 to 100; and (B) a photoinitiator. In a fourth aspect of the present invention,. A method for forming a film incorporating the curable composition of the third aspect is provided. As used herein, the term "acrylate" refers to esters of acrylic acid and the term "methacrylate" refers to esters of methacrylic acid. As used herein, the term "substantially free" means less than 0.5% by weight. As used herein, the term "oligomer" refers to a polymer prepared from ethylenically unsaturated monomers, with a degree of polymerization in the range of 2 to 100. The curable compositions of the present invention are believed to cure by the formation of bonds covalent through the reactions between the alkoxysilane-containing oligomers. In the presence of a catalyst, the alkoxysilane groups can be subjected to condensation reactions, which lead to the formation of bonds between the chains of the oligomer and an increase in the molecular weight of the composition. Curing can be as simple as the formation of a single Si-O-Si interlacing between the two different oligomer chains or can be as extensive as the formation of a network of Si-O-Si entanglements, through the curable composition. The oligomer component of the curable composition is an alkoxysilane-containing polymer. The oligomers are prepared by polymerizing the ethylenically unsaturated alkoxysilane, the monomers or acyloxysilane mixtures of these monomers, to form oligomers or with other monomers to obtain co-oligomers. The selection of the monomers is dependent on many factors, including the intended end use of the curable composition, the viscosity of the curable composition and the costs of the monomers. Suitable monomers of alkoxysilane and acyloxysilane include, for example, vinyl alkoxysilanes, allyl alkoxysilanes, acryloxyalkyl alkoxysilanes, methacryloxyalkyl alkoxysilanes, vinyl acyloxysilanes. Preferred vinyl alkoxysilane monomers are vinyl trialkoxysilanes, vinyl monoalkyldialkoxysilanes and vinyl dialkyl monoalkoxy silanes, wherein the alkyl groups contain from 1 to 6 carbon atoms and the alkoxy group contains from 1 to 6 carbon atoms. Examples of preferred alkoxysilane and acyloxysilane monomers include vinyl trimethoxysilane, vinyl triethoxysilane, vinyl triisopropoxysilane, vinyl triacetoxysilane, vinyl methyldimethoxysilane, vinyl dimethylethoxysilane, allyl trimethoxysilane, 3-acryloxypropyl trimethoxysilane, 3-acryloxypropyl methyldimethoxysilane , methacryloxymethyl triethoxysilane, methacryloxysilane methacryloxypropyl and methacryloxymethyl bis (trimethylsiloxy) silane.

Ethylenically-optional unsaturated monomers suitable for copolymerization with the ethylenically unsaturated alkoxysilane and acetoxysilane monomers are the esters of acrylates, methacrylate esters, acrylate amides, methacrylate amides, vinyl aromatics and vinyl esters of carboxylic acids. Examples of ethylenically unsaturated monomers include methyl acrylate, ethyl acrylate, butyl acrylate, hexyl acrylate, ethylhexyl acrylate, lauryl acrylate, methyl methacrylate, butyl methacrylate, N, N-dimethylaminopropyl methacrylamide, vinyl acetate. and styrene. Preferred monomers are ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, vinyl acetate and methyl acrylate. As used herein, the term "co-oligomer" is defined as an oligomer containing an alkoxysilane or acyloxysilane monomer and at least one other monomer. The monomer units of the co-oligomer are arranged to form alternative, random or block polymer structures. Oligomers formed from more than two different types of monomers, such as terpolymers or "ter-oligomers" are also considered. In the broadest sense, it will be understood that in an oligomer with a degree of polymerization equal to N, the monomer units of N can be independently selected, so that it will be possible to form an oligomer with many monomers other than N. In a sample of co-oligomer, prepared from an alkoxysilane or acyloxysilane monomer and at least one other monomer, the compositions of the individual oligomer chains may contain various ratios of two or more monomers, including a small fraction of ho or oligomers, formed of each of the monomers. The compositions of the oligomers presented herein, with the average molar ratios of the individual monomer units contained within the oligomers of the curable composition. The average range of the composition of the oligomers of the curable composition can vary from the oligomers composed only of the alkoxysilane monomer or the acyloxysilane or mixtures of the alkoxysilane and / or acyloxysilane monomers to the co-oligomer compound of an average of one unit of 1-alkoxysilane monomer or 1-acyloxysilane monomer per oligomer chain. A preferred range of the composition of the alkoxysilane or acyloxysilane monomer to the other monomer is from 1:10 to 4: 1, and a more preferred range is from 1: 6 to 2: 1. There are several synthetic methods for preparing the oligomers of the curable composition, which include the polymerization of ethylenically unsaturated alkoxysilane or acyloxysilane monomers, or mixtures of these monomers with other ethylenically unsaturated monomers. Polymerization methods include anionic polymerization, as described in U.S. Patent No. 4,056,559, radical polymerization in solution or in bulk, as described in U.S. Patent No. 5,739,238, radical polymerization with chain transfer agents, such as cobalt complexes, as described in Polymer Preprints, 1998, Vol 39 (2), pp. 459-460, by Steward et al., The catalytic polymerization of chain transfer, with terminally unsaturated oligomers, used as chain transfer agents, as described in US Pat. No. 5,264,530, radical polymerizations high temperature, in batches, stirred tank or tubular reactors. The polymerization processes can be batch, semi-continuous or continuous processes. An alternative synthetic method for producing the oligomers of the curable composition is to bind the alkoxysilane or acyloxysilane groups on an existing oligomer, as described in U.S. Patent No. 4,707,515. A preferred process for preparing the oligomers is the continuous polymerization of unsaturated alkoxysilane or acyloxysilane monomers with other monomers. The first step of this preferred process is to form a reaction mixture containing: (a) from 0.5 to 99.95% by weight of the reaction mixture of one or more ethylenically unsaturated alkoxysilane or acyloxysilane monomers, and, optionally, one or more than other ethylenically unsaturated monomers; (b) from 0.05 to 25% by weight, based on the weight of the ethylenically unsaturated monomer, of at least one free radical initiator; (c) from 0 to 99.5% of the solvent, based on the weight of the reaction mixture. Preferably, the reaction mixture contains from 10 to 99.95% by weight and, more preferably, from 50 to 98% by weight, based on the weight of the reaction mixture, of at least one ethylenically unsaturated monomer. Preferably, the reaction mixture contains from 0.1 to 5% by weight and, more preferably, from 1 to 3% by weight, based on the weight of the ethylenically unsaturated monomer, of at least one free radical initiator. The preferred process is suitable for forming oligomers of the ethylenically unsaturated alkoxysilane or acyloxysilane monomers and co-oligomers of the ethylenically unsaturated alkoxysilane and / or acyloxysilane monomers with other ethylenically unsaturated monomers. The initiators for carrying out the process of the present invention are any conventional free radical initiators, including, but not limited to, hydrogen peroxide, alkyl hydroperoxides, dialkyl peroxides, peresters, percarbonates, persulfates, peracids, oxygen, ketone peroxides, azo initiators and their combinations. Specific examples of some suitable initiators include hydrogen peroxide, oxygen, t-butyl hydroperoxide, tertiary dibutyl peroxide, tertiary amyl hydroperoxide, methylethyl ketone peroxide and combinations thereof.

The monomers can be polymerized as a solution diluted in a solvent, although the preferred process does not require solvent, it is not the use of these solvents that is preferred. The reaction mixture may contain one or more solvents at a level of 0 to 99.5% by weight of the reaction mixture, preferably 0 to 70% by weight of the mixture and, more preferably, 0 to 55% by weight of the reaction mixture. Suitable solvents for the preferred process are capable of dissolving this one or more monomers, especially under supercritical fluid conditions of the process, and the oligomers formed therefrom. Suitable solvents for the present invention include, for example, ethers, such as tetrahydrofuran, ketones, such as acetone; esters such as ethyl acetate; alcohols, such as methyl alcohol and butyl alcohol; alkanes, such as hexane and heptane; aromatic hydrocarbons, such as benzene, toluene and xylene; supercritical fluids, such as carbon dioxide; and its mixtures. Supercritical fluids, such as carbon dioxide, are particularly useful, because the solvent is easily separated from the product and can be recycled.

In the second step of the preferred process, the reaction mixture is continuously passed through a heated zone, in which this reaction mixture is maintained at a temperature of at least 150 ° C, under a high pressure. Once the reaction mixture is formed, it is preferable that the passing reaction mixture reach the polymerization temperature as rapidly as possible. Preferably, the reaction mixture reaches the polymerization temperature within 2 minutes, more preferably within 1 minute, and especially preferred within 30 seconds. Before reaching the reaction temperature, the reaction mixture can be at any suitable temperature, preferably at a temperature of 20 to 450 ° C, more preferably at a temperature of 20 to 60 ° C. The polymerization is conducted at a temperature of at least 150 ° C and preferably at a temperature in the range of 200 to 500 ° C and more preferably at a temperature in the range of 275 to 450 ° C. The oligomerization at high temperatures of the preferred process is rapid. Thus, the reaction mixture can be maintained at a polymerization temperature for as little as 0.1 second to 4 minutes, preferably 0.5 seconds to 2 minutes, more preferably 1 second to 1 minute. The elevated temperatures of the polymerization require that the polymerization reactor be equipped to operate at high pressures of at least 30 bar, to maintain the contents of the reactor as a fluid at the reaction temperature. In general, it is preferred to conduct the polymerization at 70 to 350 bar and more preferably 200 to 300 bar. In the preferred process for producing the oligomers of the present invention, the ethylenically unsaturated monomers, initiator and, optionally, the solvent combine to form a reaction mixture. The order of combining the components of the reaction mixture is not critical to the process of the present invention. In one embodiment of the present preferred process, it may be convenient to use one or more solvents, heat this one or more solvents at an elevated temperature and add the one or more monomers and at least one initiator to the heated solvent, to form the reaction mixture. It is preferred to add the initiator to the last one. The reaction mixture can be formed at a temperature below, at or above the polymerization temperature. Suitable reactors for producing the oligomers of the present invention by the preferred process include tubular reactors which have no moving parts, such as internal rotors or reactors, which have no moving parts. These reactors can have any configuration in cross section that allows continuous flow, steady state, which can operate under high temperatures and pressures. Such reactors are typically manufactured from inert materials, such as stainless steel or titanium. The reactor can be of any length and dimension in cross section, which allows effective temperature and pressure control. The preferred process for producing the oligomers of the present invention generally results in a conversion of the monomers in the oligomers of 10 up to more than 95%, relative to the initial amount of one or more of the monomers present in the reaction mixture. If the levels of the residual monomers in the oligomer mixture are unacceptably high for a particular application, their levels can be reduced by any of several techniques known to those skilled in the art, including rotary evaporation or film evaporation by rubbing, distillation and vacuum distillation. Preferably, any monomer that may be present in the oligomer is distilled or "separated" and recycled for further use. The preferred process for producing the oligomers included in the curable composition of the present invention results in oligomers having low molecular weights and narrow polydispersities. Also, process modalities result in products that do not require the removal of organic solvents (if none is used in the process) and are not contaminated with the high salt levels of initiator fragments, chain transfer agents or other processing aids. the synthesis The preferred process can be used to produce oligomers having a degree of polymerization in the range of 2 to 100, preferably in the range of 3 to 50, and more preferably in the range of 4 to 25, wherein the degree of polymerization is the number of residues of the monomer units ethylenically instantaneously in an oligomer chain.

The consistency of the products varies from a thin fluid, water type, to a viscous, marshmallow fluid. Likewise, they do not require the use of solvents in the preparation or use and are substantially free of contaminants, including salts, surfactants, metals and the like. Many catalysts are known for the curing of alkoxysilane-containing oligomers, including organic acids, such as p-toluenesulfonic acid, trifluoroacetic acid, methanesulfonic acid, trifluoromethanesulfonic acid and n-butylphosphonic acid, inorganic acids, such as phosphoric acid, metal salts of organic acids, such as tin naphthenate, tin benzoate, tin octoate, tin butyrate, dibutyltin dilaurate, dibutyltin diacetate, iron stearate and lead octoate, and bases organic, such as isophorone diamine, methylene dianiline and imidazole. The "catalysts" herein include salts that generate a catalyst in the application of heat. Photoacids and photobases, which require exposure to radiation to generate the active form of the acid or base, are excluded from the "catalysts" here. A preferred catalyst is p-toluenesulfonic acid. The catalysts are added at various levels, depending on the intended use and the method of application of the curable composition. A low level of catalyst is often selected to provide sufficient time to allow the soaking of the substrate and the leveling of the curable composition, before the composition is gel-formed. Effective catalyst levels are in the range of 0.01 to 10%, preferably in the range of 0.05 to 5% and more preferably in the range of 0.1 to 1%, based on the weight of the material containing the alkoxysilane or acyloxysilane in the curable composition. This curable composition, which includes an inorganic pigment, such as titanium dioxide, may require a higher level of catalyst to effect cure, than in the curable composition without the inorganic pigment. The catalyst can be added as a net material or diluted in a solvent. The oren addition of the oligomer and the catalyst is not important. Typically, the smaller volume of the catalyst is added to the larger volume of oligomer with sufficient mixing to provide a uniform concentration of the catalyst in the curable composition. This curable composition, which includes the oligomer and the catalyst, is a stable mixture, in the absence of moisture. Alternatively, the oligomer and catalyst can be stored separately and mixed immediately before use. The curable composition may optionally contain a solvent. The selected solvent and level are typically based on many factors, including compatibility with the other components of the curable composition, the cost, the volatility of the solvent and the desired application viscosity of the curable composition, various solvents or solvent mixtures. they may be employed, which include alcohols, such as methanol, ethanol and isopropanol, aromatic hydrocarbons, such as toluene, xylene and naphtha, ether alcohols, such as ethylene glycol -monoethyl ether, ethylene glycol monobutyl ether , propylene glycol monoethyl ether, ketones, such as methyl ethyl ketone, methyl isobutyl ketone and esters, such as butyl acetate. It is preferred that the oligomer of the curable composition be completely soluble in the solvent, but the oligomer may also be provided as a dispersion. The solid levels of the oligomer of the curable composition can be in the range of 1 to 100%, preferably in the range of 20 to 100%, and more preferably in the range of 40 to 100%, based on the weight of the non-solvent components. In another embodiment, the curable composition can be provided with low viscosities, without the addition of solvent, in which the viscosity of the curable coating is below 15 Pascal -seconds, preferably below 5 Pascal -seconds, and more preferably below 1 Pascal -second, as measured by the Brookfield DV-I + viscometer, with the LV axes at 20 ° C. The curable compositions of the present invention may contain other ingredients, including pigments, fillers, fibers, dyes, biocides, including mildiucides and fungicides, plasticizers, humectants, adhesion promoters, surfactants, soaking agents, and flow aids. , to modify the rheology and the flow. In addition, the curable compositions can be modified by the addition of other polymers, which include the dispersion, emulsion and solution polymers. These polymers can be non-reactive or can be functionalized with several reactive groups, to provide a second curing resource of the curable composition, for example, the reaction between alcohol groups and isocyanates, to form urethane linkages. Various techniques can be employed to apply the curable composition to substrates, which include spraying, dipping, brushing, curtain coating, and lay-on applicators. The curable compositions of the present invention cure rapidly upon exposure to moisture or expose to temperatures greater than 70 ° C in the absence of moisture. The moisture level is not critical in achieving cure, although the cure rate is dependent on the level of humidity in combination with other factors, such as the thickness of the curable composition applied, the level of the catalyst and the type of catalyst. Suitable moisture levels are 1% or more of relative humidity, at temperatures of 0 ° C and higher, preferably 5% or more of relative humidity at temperatures of 0 ° C and higher and more preferably 10% or more of humidity relative and temperatures of 0 ° C and higher. Humidity levels below 5% are sufficient to provide healing, although the cure rate may be insufficient for many applications. The curable composition cures at room temperature, as well as at both higher and lower temperatures. In another embodiment, the photocurable compositions containing the alkoxysilane and / or acyloxysilane oligomers are prepared. The photocurable compositions include a photoinitiator which, on exposure to actinic radiation, generates an acid or base catalyst. The photoinitiators included in this invention are often referred to as photoacids or photobases and are selected based on many factors, including the wavelength region of the photodissociation, the absorption strength and the cost. Preferred are the photocatalysts which are soluble in the oligomer of the photocurable composition. Examples of photoacids and photobases are discussed in Progress in Polymer Science, 1996, Vol 21, p. 1-45, by Shiari and Tsunooka and include, but are not limited to, aryldiazonium salts, diarylhalonium salts, triarylsulfonium salts, nitrobenzyl esters, sulfones, O-acyloximes and cobalt amines (III). Mixtures of photo-acidic photoinitiators or photobasic initiator mixtures can be used to optimize the absorption region and optical depth of the curable composition. The range of photoinitiator levels may be from 0.1 to 20%, preferably from 1 to 15% and more preferably from 2 to 10% by weight of the photoinitiator, based on the weight of the solids of the photocurable composition. Healing is preferably affected by exposure of the cancer composition containing the photoinitiator to moisture during irradiation, after irradiation or both. Effective humidity levels are similar to those discussed above. The photocurable composition of this invention is irradiated with actinic radiation at various wavelengths. The optical region of radiation wavelength is determined by the absorption characteristics of the photoinitiator or mixture of photoinitiators and is typically in the ultraviolet and visible wavelength region of 200 to 700 nm. The photocurable composition is stable when stored to minimize exposure to ambient light. The photocurable composition can be prepared as previously described for the curable composition of the first aspect of this invention and can be applied by similar methods. The curing composition and photocurable composition of the present invention are useful in many applications, including, for example, protective films and coatings, barrier coatings, caulks, clear coatings, sealants, automotive finishes, metal finishes, exterior coatings for concrete, masonry and stone, binders for non-woven fibers, adhesives and surface treatments. Preferred surface treatments include sizing agents and coupling agents for hydroxyl functional surfaces, such as glass, glass fibers, wood, aluminum and minerals, such as talc, titanium dioxide, mica, wollastonite, silicates and oxides of metal . The following examples are presented to illustrate the invention. Oligomers were prepared by a continuous high temperature polymerization process. The polymerization reactor had a longitudinal section of 3.05 meters of stainless steel pipe, which has an internal diameter of 1.6 mm) and a wall thickness of 1.3 mm connected at one end to a high pressure pump (Hewlett Packard, Model HP 1050 TI) and at the other end to a retro-pressure control device. Between the two ends, the pipe section was wound around a metal mandrel, of toroidal shape. The mandrel was placed on top of a primary coil of a transformer, so that the coils of the pipe and mandrel functioned as secondary coils of the transformer. The pipe coils were further equipped at one end of a temperature probe. The other end of the temperature probe was connected to a temperature control device. This temperature control device regulated the current supplied to the primary winding of the transformer, which regulates the heat of inductance imparted to the rolled steel pipe. A reaction mixture was prepared by mixing a solvent (if present), ethylenically unsaturated silane monomers, other monomers (if present) and an initiator. Nitrogen was bubbled through the mixture, with stirring. Under the solvent-free conditions, the initiator and the monomer / comonomers were fed separately into the reactor. The solvent was pumped through the pipeline by means of a high pressure pump at a rate of 0.05 to 10 milliliters per minute (ml / min). The pressure was maintained at a level of 200 to 350 bar. The current was supplied to the primary coil of the transformer to increase the temperature inside the pipe to the desired polymerization temperature. After about 15 minutes, the solvent that was pumped through the pipe was repl by the reaction mixture, which was pumped continuously through the pipe at the same rate, temperature and pressure. After allowing the solvent to clear from the pipe, the product was collected as the effluent from the back-pressure control device. When the addition of the reaction mixture was almost complete, the solvent was pumped through the pipe at the same rate, pressure and temperature, as the reaction mixture. The solvent and the residual monomers were removed in a rotary evaporator or a rubbed film evaporator.

The composition and molecular weight of the oligomers can be determined by many conventional analytical techniques. In the following examples, the oligomers were characterized by infrared spectroscopy, gel permeation chromatography ("GPC") and magnetic-nuclear resonance spectrum ("NMR"). The molar ratio of the monomers in each oligomer was determined by the NMR of protons or by gas chromatogaphy of the residual monomers in the sample of the doped oligomer. The number average molecular weight (Mn) and the weight average molecular weight (Mw) were determined by gel permeation chromatography (GPC) using appropriate molecular weight standards. The average formula of the oligomer was calculated from Mn and the molar ratio of monomers in the oligomer. The polydispersity of the oligomer was calculated from the ratio of Mw to Mn. The degree of polymerization of an oligomer is the number of monomer units incorporated in the oligomer backbone and is calculated from the molar ratio of the monomers in the oligomer and Mn. EXAMPLE 1 Preparation of Oligomer Ethyl acrylate (EA) monomer and vinyltrimethoxysilane (VTMO), in a molar ratio of 1: 1, were mixed with 2% di-t-butyl peroxide, based on the weight of the monomer, to form the reaction mixture. This reaction mixture was fed into the high temperature reactor continuously and heated to 300 ° C at 241 bar with a flow of 5 ml / min. The residual monomer was removed using a rotary evaporator. Average composition of the oligomer: 3.9 EA / 2.1 VTMO Mw 1700 Mn 700 Polydispersity 2.4 Viscosity 0.20 Pascal-sec.

The average composition of oligomers is presented as a molar ratio.

EXAMPLE 2 Preparation of the Oligomer Ethyl acrylate (EA) monomer and vinyltrimethoxysilane (VTMO), in a molar ratio of 2: 1, were mixed with 2% di-t-butyl peroxide, based on the weight of the monomer, to form the reaction mixture. This reaction mixture was fed into the high temperature reactor continuously and heated to 300 ° C at 241 bar with a flow of 5 ml / min. The residual monomer was removed using a rotary evaporator. Average composition of the oligomer: 3 EA / 2 VTMO Mw 1100 Mn 590 Polydispersity 1.9 Viscosity 0.13 Pascal-sec.

EXAMPLE 3 Preparation of Oligomer Butyl acrylate monomer (BA) and vinyltrimethoxysilane (VTMO), in a molar ratio of 1: 1, were mixed with 2% di-t-butyl peroxide, based on the weight of the monomer, to form the reaction mixture. This reaction mixture was fed into the high temperature reactor continuously and heated to 300 ° C at 241 bar with a flow of 5 ml / min. The residual monomer was removed using a rotary evaporator. Average composition of the oligomer: 4.3 BA / 2.4 VTMO Mw 2100 Mn 900 Polydispersity 2.3 Viscosity 0.19 Pascal-sec.

EXAMPLE 4 Preparation of the Oligomer The oligomer was prepared by feeding a 50% by weight solution in heptane of a 1: 1 molar ratio of VTMO and styrene, containing 2% di-t-butyl peroxide, based on weight of the monomer, at 5 ml / min through a high temperature reactor continuously, at a temperature of 300 ° C to 241 bar. The residual monomers and the heptane solvent were removed from the oligomer product in a rotary evaporator. Average composition of the oligomer: 3.4 Styrene /O.5 VTMO Mw 1500 Mn 430 Polydispersity 3.5 Viscosity > 80 Pascal-sec.

EXAMPLE 5 Preparation of the Oligomer The oligomer was prepared by feeding a 50% by weight solution in heptane of a molar ratio of 1: 1.

VTMO and vinyl acetate (Vac), which contains 2% di-t-butyl peroxide, based on the weight of the monomer, at 5 ml / min through a high temperature reactor in a continuous, at a temperature from 275 ° C to 241 bars. The residual monomers and the heptane solvent were removed from the oligomer product in a rotary evaporator. Average composition of the oligomer: 2.6 VAc / 3.1 VTMO Mw 2300 Mn 690 Polydispersity 3.3 Viscosity 0.31 Pascal-sec EXAMPLE 6 Preparation of the Oligomer The oligomer was prepared by feeding a 50% by weight solution in ethanol of a molar ratio of 2: 1 of ethyl acrylate and vinyltriethoxysilane (VTEO) containing 2% di-t-butyl peroxide, with based on the weight of the monomer, at 5 ml / min through a high temperature reactor continuously, at a temperature of 300 ° C at 241 bar. The residual monomers and the solvent were removed from the oligomer product in a rotary evaporator. Average composition of the oligomer: 5.9 EA / 1.7 VTEO Mw 2100 Mn 920 Polydispersity 2.3 Viscosity 0.073 Pascal-sec EXAMPLE 7 Preparation of the Oligomer The oligomer was prepared by feeding a 50% by weight solution in methanol of a molar ratio of 2: 1 ethyl acetate and vinylmethyldimethoxysilane (VMDMO) containing 2% di-t-butyl peroxide, with based on the weight of the monomer, at 5 ml / min through a high temperature reactor continuously, at a temperature of 300 ° C at 241 bar. The residual monomers and the solvent were removed from the oligomer product in a rotary evaporator. Average composition of the oligomer: 4.1 EA / 1.1 VDMO Mw 1020 Mn 560 Polydispersity 1.8 Viscosity 0.13 Pascal-sec.

EXAMPLE 8 Curable Composition and Comparative Example Crystals of p-toluenesulfonic acid (pTSA) were dissolved in methanol to prepare a catalyst solution at 10% solids. The catalyst solution was added, with stirring, to the net oligomer and to a solution of 50% oligomers in toluene, to form curable compositions. The titanium tetraisopropoxide was added in net form to the oligomer. Films were prepared by applying the curable compositions on glass cursors with a laying applicator (8-Path Wet Film Applicator, Paul N. Gardner Company). The curable, toluene-containing compositions were applied at a wet thickness of 0.127 mm, which was dried to a thickness of approximately 0.051 mm. The curable compositions without toluene were applied at a wet thickness of 0.0508 mm. The films were allowed to cure at ambient conditions for 30 minutes. The cure was evaluated by touching the film to determine if the sample was solid. The strength of the cured film was characterized by resistance to deterioration and was evaluated by striking the sample with the fingernail. The curable compositions of the invention containing the catalyst (Examples 8-1 to 8-5) cured solid films in 30 minutes or less.

Table 8.1 Evaluation of the Curable Composition and Comparative Composition EXAMPLE 9 Effect of Catalyst Level Oligomers were prepared as 50% solutions in toluene. PTSA, a 10% solution in methanol, was added to the oligomer solutions with agitation, to prepare the curable compositions. The films were prepared by applying the curable compositions on glass cursors with a laying applicator (Wet Film Applicator, 8 Trajectories, Paul N. Gardner Company). The curable compositions were applied with a wet thickness of 0.127 mm, which was dried to a thickness of approximately 0.051 mm. After 15 minutes of exposure to environmental conditions, the films were found to be resistant to deterioration, striking them with the fingernail. The results of Table 9.1 show that the curable compositions of this invention (Examples 9-1 to 9-12) cure with various catalyst levels.

Table 9.1 Effect of TSA level on healing EXAMPLE 10 Pigmented Curable Composition A pigmented curable composition was prepared by adding 25 g of Ti -Pure® (EI du Pont de Nemours &CO.) R-706, titanium dioxide, and 25 g of the oligomer of Example 1 to 118 ml of a shot mill containing 50 g of zirconia beads and shaking the mixture for 10 minutes on a paint shaker. A 10% solution of pTSA in methanol, as a catalyst, was added to the mixture of oligomers and pigment. A film with a wet thickness of 0.102 mm was applied, with a laying sheet on an aluminum panel.

Table 10.1 Effect of catalyst level on curing pigmented curable compositions The catalyst level was% by weight of the catalyst, based on the weight of the oligomer. The results of Table 10 show that the curable compositions pigmented with titanium oxide required a higher level of the pTSA catalyst to effect cure in less than 1 hour, than the non-pigmented curable compositions in Examples 9-1 to 9-3. The pTSA catalyst is believed to be deactivated on the surface of the titanium oxide pigment.

EXAMPLE 11 Curing by the Sol-Gel Process The oligomers were weighed in Teflon® laboratory cuvettes (E. I. du Pont de Nemours &Co.). First, deionized water was added to the oligomer and mixed. The pH was then adjusted by the addition of 0.01N HCl. Finally, ethanol was added to the oligomer mixture. The laboratory cuvette was covered to prevent evaporation of the solvents. After two days, the cuvette was discovered and the solvents evaporated to supply hard rubber-like disks, with a clear uniform appearance.

Table 11.1 Ingredients Used in the Preparation of Sol-Gel The disc was approximately 3 cm in diameter by 1 cm in thickness, which indicates that Examples 11-1 and 11-2 of this invention healed.

EXAMPLE 12 Photocurable Composition Photocurable compositions were prepared by mixing the oligomer of Example 1 with photoinitiators. The 0.051 mm thick coating of the photocurable composition was applied on glass cursors with a laying applicator (Wet Film Applicator, 8 Trajectories, Paul N. Gardner Company) and irradiated by passing the coated substrate through a processor of UV (PPG QC 1201 UV Processor). After exposure to a radiation dose of 4 watts / cm2, the coatings were initially cured only at the top, but then cured to clear films, resistant to deterioration, in 3 minutes. Table 12.1.1 Effect of the type of photoinitiator in the photocuring of the oligomer of Example 1 SarCat® CD1010 (Sartomer): triaryl sulfonium hexafluoroanthionate SarCat® CD1011 (Sartomer): triaryl sulfonium hexafluorophosphate Irradiation of the photocurable compositions of Examples 12-1 and 12-2 of this invention, which contain the photoacids, exhibited good healing Irradiation of the sample without the photoinitiator (Comparative D) and with the radical that generates the benzophenone photoinitiator (Comparative C) remained liquid, after UV exposure, indicating that the cure to supply a film, did not happen under these conditions-

Claims (10)

1. CLAIMS 1. A curable composition, which comprises: (A) an oligomer, prepared by a continuous process, of one or more monomers selected from the group consisting of ethylenically unsaturated alkoxysilanes and acyloxysilanes monomers, and, optionally, one or more of other ethylenically unsaturated monomers, where these monomers are polymerized at temperatures of 150 to 500 ° C, in which the oligomer has a degree of polymerization of 2 to 100; and (B) a catalyst.
2. 2. The curable composition of claim 1, wherein the oligomer is polymerized from the vinyl trimethoxysilane monomer and a second monomer, selected from the group consisting of ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, styrene and acetate. of vinyl.
3. 3. The curable composition of claim 1, wherein the oligomer has a molar ratio in the range of 1:10 to 4: 1 of ethylenically unsaturated alkoxysilane and acyloxysilane monomer residues to residues of other ethylenically unsaturated monomers.
4. 4. A method to form a film by: (A) applying to a substrate a curable composition, comprising: (i) an oligomer, prepared by a continuous process of one or more monomers, selected from the group consisting of ethylenically unsaturated alkoxysilane and acyloxysilane monomers, and, optionally, one or more other ethylenically unsaturated monomers, wherein the monomers are polymerized at a temperature of 150 to 500 ° C, in which the oligomer has a degree of polymerization of 2 to 100, and (ii) a catalyst; and (B) cure the composition
5. 5. A photocurable composition, which comprises:
6. (A) an oligomer, which includes parts selected from the group consisting of alkoxysilane and acyloxysilane moieties, wherein the oligomer is prepared from the polymerization of ethylenically unsaturated monomers, wherein the oligomer has a degree of polymerization of 2 to 100; and (B) a photoinitiator, selected from the group consisting of photoacids and photobases.
7. 7. The composition of claim 6, wherein the oligomer is prepared by a continuous process from one or more monomers selected from the group consisting of ethylenically unsaturated alkoxysilane and acyloxysilane monomers, one or more ethylenically unsaturated monomers, wherein the monomers are they polymerize at a temperature of 150 to 500 ° C, in which the oligomer has a degree of polymerization of 2 to 100.
8. 8. A method for forming a film by: (A) applying a photocurable composition, comprising: (i) an oligomer comprising selected portions of the group consisting of alkoxysilane and acyloxysilane portions, wherein the oligomer is prepared from the polymerization of unsaturated monomers ethylenically, wherein the oligomer has a degree of polymerization of 2 to 100, and (ii) a photoinitiator, selected from the group consisting of photoacids and photobases; (B) exposing the photocurable composition to actinic radiation; and (C) cure the composition.
9. 9. The method of claim 8, wherein the oligomer is prepared by a continuous process, from one or more monomers selected from the group consisting of ethylenically unsaturated alkoxysilane and acyloxysilane monomers, and, optionally, one or more unsaturated monomers ethylenically, where these monomers are polymerized at a temperature of 150 to 500 ° C, where the oligomer has a degree of polymerization of 2 to 100.
10. 10. A product produced by the method of claim 8.