Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/67—Unsaturated compounds having active hydrogen
  • C08G18/671—Unsaturated compounds having only one group containing active hydrogen
  • C08G18/672—Esters of acrylic or alkyl acrylic acid having only one group containing active hydrogen
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D251/00—Heterocyclic compounds containing 1,3,5-triazine rings
  • C07D251/02—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings
  • C07D251/12—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings having three double bonds between ring members or between ring members and non-ring members
  • C07D251/26—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings having three double bonds between ring members or between ring members and non-ring members with only hetero atoms directly attached to ring carbon atoms
  • C07D251/30—Only oxygen atoms
  • C07D251/34—Cyanuric or isocyanuric esters
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F120/00—Homopolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride, ester, amide, imide or nitrile thereof
  • C08F120/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
  • C08F120/10—Esters
  • C08F120/34—Esters containing nitrogen, e.g. N,N-dimethylaminoethyl (meth)acrylate
  • C08F120/36—Esters containing nitrogen, e.g. N,N-dimethylaminoethyl (meth)acrylate containing oxygen in addition to the carboxy oxygen, e.g. 2-N-morpholinoethyl (meth)acrylate or 2-isocyanatoethyl (meth)acrylate

Definitions

• the present invention relates to isocyanurates compositions useful in the preparation of polymeric isocyanurates. More particularly, the present invention relates to isocyanurates compositions which when cured have excellent physical properties at high temperatures.
• vinylidene group when used in this application means the group characterized by the formula: wherein the two free valence bonds are not both connected to the same carbon atom.
• aromatic polyisocyanate when used in this application means a compound containing at least 2 isocyanate groups attached directly to the carbon atom of an aromatic ring.
• isocyanurate means a compound containing the structure:
• thermoset resins The products of this invention may be generally classified as thermoset resins.
• the prior art thermoset resins lack one or more important physical properties which would be desirable in their use. It is an object of this invention to prepare curable thermosetting compositions which combine excellent viscosity control at low as well as high dissolved solids concentrations; which are easily handled for laminate preparation; which may be blended with copper salts to yield a low exotherm on cure to prevent bubbling and warpage; which have a broad range of solubility in vinylidene monomers with which it is copolymerizable; which when cured form thermoset resins which exhibit good corrosion resistance in a variety of media, including water, acid and alkali; and which yield cured resins with superior stiffness and rigidity and excellent retention of physical properties at elevated temperatures.
• the resins of this invention are further characterized by a very high level of aromatic and cyclic character which are derived both from the aromatic polyisocyanate and from the isocyanurate ring.
• This high degree of aromatic and cyclic character is believed to contribute substantially to the improved thermal stability and to the stiffness and rigidity of the products prepared therefrom.
• the combination of these highly aromatic and cyclic compositions with acrylate and methacrylate unsaturation makes possible a rapid curing system with excellent retention of physical properties not readily achievable from prior art products. It also allows for a versatile solubility in a variety of comonomers with which the products of this invention will copolymerize.
• the products of this invention have a molecular weight range that allows the proper solution viscosity (about 100 to about 1000 cps) for good handling and lay-up when making laminates. Products of this invention having a viscosity above 1000 cps may also be prepared for use in applications requiring high viscosity. The products of this invention can be prepared at low solids concentration and still exhibit the proper viscosity for good handling.
• the isocyanurate compositions of this invention are isocyanurates of urethanes of an aromatic polyisocyanate and at least one vinylidene carbonyl oxy alkanol characterized by one of the following formulae: and wherein R i is hydrogen or an alkyl group containing from 1 to 4 carbon atoms, R 2 is hydrogen, alkyl containing from 1 to 12 carbon atoms, or a chlorinated, brominated, or fluorinated alkyl group containing from 1 to 12 carbon atoms, R 3 is hydrogen, alkyl containing from 1 to 12 carbon atoms, or a chlorinated, brominated, or fluorinated alkyl group containing from 1 to 12 carbon atoms, R 4 is hydrogen, methyl or ethyl, and n is from one to four, with the proviso that R 2 and R 3 on adjacent carbon atoms are not both alkyl or chlorinated, brominated, or fluorinated alkyl, that is at least one of R
• the resin be prepared from an unsaturated isocyanurate composition wherein at least a major amount of the isocyanurate moieties are based on one or more vinylidene carbonyl oxy alkanols defined above.
• alkanols include; hydroxypropyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxyethyl acrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, and diacrylates and dimethacrylates of trimethylol propane, trimethylol ethane, trimethylol methane, and glycerol.
• a preferred group of vinylidene carbonyl oxy alkanols include hydroxypropyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxy ethyl acrylate and blends thereof.
• alkanols are blends of polyfunctional acrylates or methacrylates such as pentaerythritol triacrylate, pentaerythritol trimethacrylate, and mixtures thereof, with one or more monofunctional acrylates or methacrylates such as hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxyethyl acrylate, and hydroxyethyl methacrylate.
• polyfunctional acrylates or methacrylates such as pentaerythritol triacrylate, pentaerythritol trimethacrylate, and mixtures thereof
• monofunctional acrylates or methacrylates such as hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxyethyl acrylate, and hydroxyethyl methacrylate.
• the isocyanurate compositions of this invention must contain moieties derived from one of the vinylidene carbonyl oxy alkanols defined above, the moieties derived from an aromatic polyisocyanate may be based on any trimerizable aromatic polyisocyanate.
• any trimerizable aromatic polyisocyanate which is conventionally used in the art for the preparation of isocyanurates may be used to prepare the isocyanurate compositions of the present invention.
• the aromatic polyisocyanate may or may not contain ethylenic unsaturation and it may be monomeric or polymeric.
• aromatic polyisocyanate contain at least two aromatic isocyanate groups, be trimerizable, and be free of any groups which interfere with the trimerization of isocyanate groups or which interfere in the reaction of an isocyanate group with a hydroxyl group.
• aromatic polyisocyanates which are particularly useful in the preparation of isocyanurate compositions of this invention include: 2,4-tolylene diisocyanate; 2,6-tolylene diisocyanate; m-phenylene diisocyanate; p-phenylene diisocyanate; 1,5-naphthalene diisocyanate; 4,4'- diphenyl ether diisocyanate; 4,4',4"-triphenylmethane triisocyanate; 2,4,4'-triisocyanato- diphenylmethane; 2,2',4-triisocyanato diphenyl; 4,4'-diphenylmethane diisocyanate; 4,4'-benzophenone diisocyanate; 2,2-bis(4-isocyanatophenyl)propane; 1,4-naphthalene diisocyanate; 4 - methoxy - 1,3 - phenylene diisocyanate; 4 - chlor
• aromatic polyisocyanate small amounts of an aliphatic polyisocyanate, for example, 1,6-hexamethylene diisocyanate, isophorone diisocyanate, or alpha, alpha'-diisocyanato-p-xyiene, may be used in combination with the aromatic polyisocyanate.
• an aliphatic polyisocyanate for example, 1,6-hexamethylene diisocyanate, isophorone diisocyanate, or alpha, alpha'-diisocyanato-p-xyiene
• the amount of monoisocyanate used is usually selected to furnish a ratio of isocyanate groups originating with monoisocyanates to isocyanate groups originating with polyisocyanate of not more than 0.5, and preferably a ratio of not more than 0.3.
• monoisocyanates which may be used include p-tolylisocyanate, phenylisocyanate, and n-butylisocyanate.
• Preferred polyisocyanates are 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, polymethylene polyphenylene polyisocyanates having an average functionality of 2.1 to 2.7, and mixtures thereof.
• the unsaturated isocyanurate compositions of this invention are a mixture of urethane containing unsaturated isocyanurates of an aromatic polyisocyanate and at least one vinylidene carbonyl oxy alkanol characterized by one of the above formulae.
• the exact structure of each component of these compositions and the precise amount of each component present in the compositions are not known.
• the essential components of the isocyanurate compositions of this invention contain vinyl groups, ester groups, urethane groups and isocyanurate groups. It is also believed that these groups are linked together in the following sequence: vinyl-ester-urethane-isocyanurate ring.
• the preferred unsaturated isocyanurate compositions of this invention are a mixture of isocyanurates characterized by the following formulae: wherein R" is an aromatic radical free of a group which is reactive with an isocyanate group and is obtained by removing the isocyanate groups from an aromatic polyisocyanate, wherein x is an integer which is one less than the number of isocyanate groups present in the polyisocyanate, wherein each R' is independently with the proviso that at least one R' is and with the proviso that each terminal R' is wherein R"' is a monovalent organic radical having the formula obtained by removing a hydroxyl group from a vinylidene carbonyl oxy alkanol characterized by formulae (1) to (5) recited above and where each R"" is independently and wherein the total number of isocyanurate rings in each molecule is less than 400.
• esters of carboxy amino phenyl isocyanurates and vinylidene carbonyl oxy alkanols may also be described as esters of carboxy amino phenyl isocyanurates and vinylidene carbonyl oxy alkanols. These esters contain one or more isocyanurate rings per molecule or, as is usually the case, comprise a mixture of esters containing one isocyanurate ring per molecule with esters containing more than one isocyanurate ring per molecule. These esters may or may not contain allophanate groups.
• the solid isocyanurates of this invention Prior to curing, are fusible, that is, they exhibit a softening point by the Ring and Ball method described in the A.S.T.M. Designation E28-58T.
• Preferred isocyanurate compositions of this invention exhibit characteristic infra-red (IR) peaks at 5.75 - 6 microns (carbonyl), 6.1 - 6.35 microns (amidic hydrogen), 6.9 - 7.2 microns (isocyanurate), and 10.15 ⁇ 10,85 microns (vinyl).
• IR infra-red
• a preferred class of isocyanurates have IR peaks at 5.8 - 5.95 microns, 6.2 - 6.3 microns, 7.00 - 7.15 microns, and 10.2 - 10.75 microns.
• Preferred isocyanurates of this invention which are prepared with toluene diisocyanate and hydroxylpropyl methacrylate exhibit IR peaks in styrene at about 5.85 microns, about 6.23 microns, about 7.1 microns, and about 10.6 microns.
• the isocyanurate compositions of this invention which are styrene solutions of isocyanurates based on toluene diisocyanate and hydroxylpropyl methacrylate may be further characterized within experimental error by the following nuclear magnetic resonance (NMR) signals at: 9.6 ⁇ 0.2, 8.8 ⁇ 0.2, 7.50, 7.48, 7.44, 7.41, 7.36, 7.33, 7.29, 7.26, 6.79, 6.71, 6.57, 5.93, 5.91, 5.70, 5.69, 5.33, 5.31, and 5.19.
• NMR nuclear magnetic resonance
• the unsaturated isocyanurate compositions of this invention are all soluble in at least one of the following free-radical polymerizable ethylenically unsaturated monomers: divinylbenzene, styrene, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, butyl acrylate, butyl methacrylate, tetramethylene glycol diacrylate, trimethylol propane triacrylate, pentaerythritol triacrylate, neopentyl glycol diacrylate, 1,3-butylene glycol diacrylate, 2,3-dibromopropyl acrylate, 2,3-dibromopropyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, acrylic acid, methacrylic
• the ethylenically unsaturated isocyanurate compositions of this invention may be prepared by reacting an aromatic polyisocyanate with one of the above-described vinylidene carbonyl oxy alkanols to form an isocyanate containing urethane and then trimerizing the isocyanate-containing urethane until essentially all isocyanate groups have reacted to form the ethylenically unsaturated isocyanurate composition of this invention. It will be understood, of course, that the resulting isocyanate composition may contain some residual isocyanate groups. Other methods of preparing the isocyanurates will be apparent to those skilled in this art.
• the isocyanurate compositions of this invention may be prepared by the method described in European patent application published under the number 0000658 and entitled " PROCESS FOR PREPARING ETHYLENICALLY UNSATURATED ISOCYANURATES". Briefly, this process is a two-step process which comprises a first step of reacting an aromatic polyisocyanate with a vinylidene carbonyl oxy alkanol in the presence of a copper salt, such as cupric acetate, to form an isocyanate-containing urethane and a second step of trimerizing the isocyanate-containing urethane in the presence of an isocyanate trimerization catalyst to form the ethylenically unsaturated isocyanurate composition of this invention.
• a copper salt such as cupric acetate
• the solution viscosity of the unsaturated isocyanurate compositions of this invention can be varied over a wide range by adjusting the stoichiometry of the aromatic polyisocyanates and vinylidene carbonyl oxy alcohols employed in their synthesis and/or the temperature of the trimerization.
• varying the degree of the excess isocyanate groups compared to hydroxyl groups it is possible to adjust the formation of high molecular weight species and solution viscosities at a fixed concentration.
• Increasing the excess of isocyanate groups compared to hydroxyl groups favors higher molecular weight species and therefore higher viscosities
• conversely lowering the excess isocyanate groups compared to hydroxyl groups favors lower molecular weight species and therefore lower viscosities.
• the solution viscosity is also increased as the temperature used in the trimerization reaction increases, but this is not as important a variable as the excess of isocyanate groups compared to hydroxyl groups.
• the trimerization temperature is most often maintained from 0°C. to 95°C, since the trimerization reaction is slow at lower temperature and higher temperature may cause the vinylidene group to polymerize prematurely.
• a preferred trimerization temperature is from 50°C to 90°C.
• Allophanate-free isocyanurate may be prepared by conducting the trimerization at a temperature of above 85°C. Allophanate-free isocyanurates may be prepared also by heating an allophanate-containing isocyanurate product of this invention to a temperature of, preferably, from 85°C. to 95°C. in the presence of a trimerization catalyst. Higher temperatures may be employed subject to the stability of the resin system.
• the isocyanurate products of this invention usually have an allophanate content sufficient to give an allophanate to urethane stoichiometric ratio of from 0 to 0.7, and preferably from 0 to 0.2, as determined by NMR measurements.
• Allophanate free resins may be prepared for the preparation of thick laminates in order to minimize gas evolution at elevated temperatures.
• isocyanurate compositions of this invention may contain as a by-product urethanes which do not contain an isocyanurate ring. These urethanes may be formed by the reaction of all the isocyanate groups of the polyisocyanates used with hydroxyl groups from the vinylidene carbonyl oxy alkanol used.
• isocyanurate compositions of this invention made with tolylene di-isocyanate and hydroxypropyl methacrylate may contain as a by-product the diurethane of one mole of tolylene diisocyanate and two moles of hydroxypropyl methacrylate. These urethanes may be characterized by the formula where R .
• R b is where R c is a monovalent organic radical having the formula obtained by removing a hydroxyl group from a vinylidene carbonyl oxy alkanol characterized by formula (1) to (5) recited above.
• the amount of such urethanes present in the compositions of this invention will depend mainly on the trimerization temperature and on the hydroxyl to isocyanate ratio used to prepare the isocyanurate composition.
• the amount of such urethanes may amount to up to 65% by weight but more usually in the range of 10% to 50% by weight of the total composition.
• the amount of high molecular weight polyisocyanurate structure is increased by increasing the excess of isocyanate groups to hydroxyl groups.
• the amount of these species may also be controlled by adjusting the trimerization temperature.
• Table I illustrates ways to obtain vinylidene carbonyl oxy alkanol containing urethane isocyanurate solutions over a broad viscosity range.
• Table I refers to the reaction products from hydroxypropylmethacrylate (HPMA) and toluene diisocyanate (TDI) dissolved in styrene, those skilled in the art will understand that similar relationships hold true for other solvent systems using other polyisocyanates or vinylidene alcohols.
• the examples in Table I illustrate the effect of the three important reaction parameters on the viscosity of the final product. Examples F and G as well as H and I show the effect of trimerization temperature on the viscosity of the final product.
• Examples D and F and J and L illustrate the effect of concentration on the viscosity
• examples B and C, E, F and I and also J and K demonstrate the effect of the molar excess of NCO groups compared to hydroxyl groups per mole of polyisocyanate, on the viscosity of the final product.
• All reactions listed in the table were carried to completion, i.e., the residual isocyanate content was essentially zero. Additional viscosity control may be achieved also by stopping the reaction short of completion as can be done in the usual manner by adding active hydrogen compounds compatible with the system and/or destruction of the trimerization catalyst. All reaction runs are in styrene using HPMA and TDI.
• reaction runs B through L were made using the procedure outlined in example 1 whereas reaction run A was made according to the procedure outlined in example 8.
• the procedure used for run A involves a somewhat different mode of addition of polyisocyanate than used in runs B through L and is used primarily for the synthesis of low concentration products.
• the isocyanurate compositions of this invention be based on one of the vinylidene carbonyl oxy alkanols defined above in order to obtain products having excellent high temperature properties
• a minor amount of moieties derived from the vinylidene carbonyl oxy alkanols may be replaced with moieties derived from other monohydric alcohols, dihydric alcohols, monohydric phenols, or dihydric phenols.
• the saturated monohydric alcohols are especially useful with polyisocyanates of functionality greater than two.
• the high temperature properties decrease as the amount of vinylidene carbonyl oxy alkanol decreases
• the flame-retardance properties may be introduced by substituting a minor amount of the vinylidene carbonyl oxy alkanol with a phosphorus or fluorine chlorine or bromine containing alcohol or phenol.
• low smoke properties may be introduced by substituting a minor amount of the vinylidene carbonyl oxy alkanol with sulphur containing alcohols or phenols.
• isocyanurate compositions of this invention While minor amounts of any hydroxyl or phenolic material may be included in the isocyanurate compositions of this invention, it should be remembered that the isocyanurate compositions of this invention must be fusible and must meet the solubility test described above and must contain at least a major amount of isocyanurate moieties derived from a vinylidene carbonyl oxy alkanol described above.
• Illustrative examples of monohydric alcohols and monohydric phenols which may be used to replace up to 49 mol percent of the vinylidene carbonyl oxy alkanols described above include: methanol, ethanol, propanol, butanol, isobutanol, octyl alcohol, cyclohexanol, benzyl alcohol, allyl alcohol, glycerol diallyl ether, trimethylolpropane diallyl ether, saturated halogenated alcohols, halogenated alcohols containing ethylenic unsaturation, for example, dibromoneopentyl glycol monoacrylate and monomethacrylate, halogenated allyl alcohols, monohydric alcohols such as 2-bromo ethanol, 3 - bromo - 1 - propanol, 4 - chloro - 1 - butanol, 2 - chlorethanol, - 4 - chloro - 1 - hexanol
• dihydric alcohols which may be used to replace up to 33 mol percent, and preferably up to 10 mol percent, of the vinylidene carbonyl oxy alkanols described above include: ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, compounds characterized by the formula: wherein R i is an alkyl group containing from 1 to 4 carbon atoms, 1,4-butane diol, pentamethylene glycol, hexamethylene glycol, glycerol methyl ether, polyoxyethylene and polyoxypropylene ethers of dihydric phenols such as bisphenol A, glycerol monochlorohydrin, glyceryl monostearate, dihyroxy acetone, and monoesters of the above polyols and acrylic acid or methacrylic acid.
• R i is an alkyl group containing from 1 to 4 carbon atoms, 1,4-butane diol, pentamethylene glycol, hex
• phenols in small amounts (up to 20 mole percent) that are reactive with aromatic isocyanates may be used in the practice of this invention.
• reactive phenols it is particularly important that essentially all of the phenolic hydroxyl groups are reacted with isocyanate groups so that unreacted hydroxyl groups will not be available to interfere with subsequent free radical curing reactions.
• Phenols such as 4-hydroxyphenyl 4'-chlorophenyl sulfone are especially useful because they characteristically improve the fire retardant and smoke properties of the product while still retaining elevated temperature retention of physical properties.
• Phenol may also be used to block a minor portion of the isocyanate functionality which may later be regenerated at elevated temperatures to produce products with improved bonding to a substrate, especially glass fibers. Nitrophenols do not react readily with isocyanates and are not within the scope of this invention.
• the unsaturated isocyanurate compositions of this invention may be homopolymerized or copolymerized with one or more other ethylenically unsaturated copolymerizable compounds.
• the isocyanurate composition may be dissolved in the copolymerizable monomer or it may be desirable to utilize the copolymerizable compound as a solvent for the reaction system in which the ethylenically unsaturated isocyanurate compositions of this invention are formed.
• the solvent should not contain any groups which would react with isocyanate groups or in any way interfere with the urethane formation reactions or trimerization reactions which occur in the formation of the isocyanurate products of this invention.
• the solvent should not contain any hydroxyl, carboxyl, or amine groups which might interfere with these reactions. This limits the suitable solvents to esters, ethers, hydrocarbons and similar solvents containing nonreactive groups.
• Nonpolymerizable solvents may also be used, for example, benzene, toluene, xylene, and ethylbenzene.
• the solvent may be removed from the reaction mixture after the formation of the isocyanurate to give a solid product.
• the solid product may be dissolved in the same or a different polymerizable solvent prior to curing. Mixtures of solvents may also be used.
• Preferred solvents are styrene, a mixture of styrene and methyl methacrylate, and a mixture of styrene and divinylbenzene.
• the product formed is a solid and requires special processing which permits the easy removal of the heat generated by the reaction and which prevents the reaction mixture from reaching high temperatures which may induce insolubility and gelation of the products.
• special processing techniques may be the trimerization of the monourethane in thin layers on moving temperature-controlled belts or in temperature-controlled trays.
• the amount of solvent employed to dissolve the isocyanurate compositions of this invention may vary over a very wide range.
• the particular amount of solvent used will depend somewhat on the nature of the solvent and on the solubility of the particular isocyanurate used.
• the polymeric character of the isocyanurate product allows maintenance of adequate working viscosity at relatively low concentrations of dissolved solids.
• Products of this invention may be made which permit adequate laminate working viscosity, which is defined as 100 to 1,000 centipoises Brookfield as determined on a Brookfield Viscometer, Model LVT, #2 spindle, at 30 rpm., at 25°C.
• the amount of solvent will also depend on the nature of the properties desired in the final cured product.
• the high temperature properties of the final product will increase as the concentration of the styrene decreases.
• the amount of solvent used will be from 5 to 95 weight percent of the total composition and preferably from 30% to 80% by weight of the total composition. A particularly preferred concentration is about 50% by weight.
• the unsaturated isocyanurate compositions of this invention and solutions thereof in a copolymerizable solvent may be polymerized or cured in accordance with polymerization conditions conventional in the art for the polymerization of ethylenically unsaturated materials.
• Isocyanurates of this invention particularly styrene solutions of isocyanurates made with tolylene diisocyanates or polymethylene polyphenylene polyisocyanate and hydroxyl propyl methacrylate, hydroxyl ethyl methacrylate, or hydroxyl propyl acrylate, are less sensitive to oxygen than conventional vinyl systems in yielding tack-free surfaces.
• the polymerization may be carried out by reacting the unsaturated isocyanurate in the presence of a polymerization catalyst
• suitable polymerization initiators include the various peroxide initiators such as benzoyl peroxide, methyl ethyl ketone peroxide, di(2-ethylhexyl) peroxydicarbonate, t-butyl perbenzoate, dicumyl peroxide, and t-butyl hydroperoxide.
• Other polymerization catalysts which may be used includes azo type initiators such as azobisisobutyronitrile.
• the amount of initiator employed is usually very small. For example, from about 1 part of initiator per 1000 parts of the polymerizable mixture to about 5 parts per 100 parts of said mixture.
• Suitable accelerators include cobalt, manganese, lead and iron compounds such as cobalt naphthenate and manganese napthenate, and tertiary amines such as dimethyl aniline.
• a small amount of a cupric salt such as cupric acetate, or a conventional polymerization inhibitor, such as hydroquinone, methyl ether of hydroquinone, phenothiazine, and tertiary butyl catechol may be incorporated either into the reaction mixture prior to preparation of the isocyanurate product or into the final product or both.
• the resulting isocyanurate product may contain any of the additives which are conventionally employed in polymerization systems, for example, antioxidants, U.V. absorbers, dyes and pigments.
• the unsaturated isocyanurate products of this invention have been found to be particularly useful in applications such as castings, coatings, and laminates where it is desirable to have excellent flexural and tensile properties and good corrosion resistance at elevated temperatures.
• Laminates prepared with wettable fibers preferably contain at least 20% by weight of isocyanurate composition and up to 80% by weight of wettable fiber. Cured products obtained from polymerizing concentrated isocyanurate solutions of this invention exhibit thermal stability at temperatures above 325°F.
• the products of this invention may be used alone or in combination with other ethylenically unsaturated monomer compositions.
• these products may be used in combination with inorganic fillers, such as calcium carbonate, magnesium oxide, aluminatrihydrate; organic polymers such as polyethylene, polymethylmethacrylate and other additives to reduce shrinkage; and fire retardant additives or other polymerizable resins, such as general purpose polyester resins.
• inorganic fillers such as calcium carbonate, magnesium oxide, aluminatrihydrate
• organic polymers such as polyethylene, polymethylmethacrylate and other additives to reduce shrinkage
• fire retardant additives or other polymerizable resins such as general purpose polyester resins.
• the products of this invention are especially useful when used in combination with glass fibers, cellulosic fibers, aramide fibers, or other fibers to produce reinforced structures, such as laminates and pipes.
• the products of this invention exhibit excellent wettability when used with these fibers.
• Laminates are prepared by rolling the indicated isocyanurate solution containing the curing reagents evenly onto glass fiber mats with a paint-type roller then rolling thoroughly with a grooved laminating roller.
• the curing reagents are added to the solution of isocyanurate in copolymerizable solvent by first adding the indicated promoter and accelerator to the isocyanurate solution and then adding the indicated peroxide 3 mm (1/8") thick laminates are prepared with two layers of split strand 457 g/m 2 (1-1/2 ounce) glass mats sandwiched between two 0.25 mm (10 mil) surfacing "C" glass mats.
• the weight of the glass is 25% of the total resin glass weight.
• 6 mm (1/4 inch) thick laminates are made by the following combination of glass mats impregnated with resin: 0.25 mm (10 mil) surfacing "C" glass mat, two layers of 457 g/m 2 of (1-1/2 ounce) chopped strand mat, 1 layer woven roving, one layer of 457 g/m 3 (1-1/2 ounce) chopped strand mat, 1 layer of woven roving and a final layer of 457 g/m 2 (1-1/2 ounce) chopped strand glass mat.
• the amount of resin used to make this 6 mm (1/4") laminate is adjusted to give a resin ratio of 70%.
• Laminates are covered with a thin polyester film to exclude air from the surface during cure. After 18-24 hours at room temperature the cured laminates are heated for 1 hour at 100°C. in an oven for postcure.
• a three-neck, round-bottom, 5-liter glass flask, equipped with thermometer, air inlet, dropping funnel, and condenser is charged with 865 ml of hydroxypropyl methacrylate, 2144 ml of styrene, 1.8 g of cupric acetate, and 800 mg of hydroquinone.
• the solution is heated to 85°C., and 852 ml of toluene diisocyanate are slowly added over a 150 min. period.
• the temperature of the reaction medium during the addition of the toluene diisocyanate is maintained between 88°C and 90°C.
• the temperature of the reaction mixture is maintained at about 90°C for an additional 90 min.
• the resulting dark green liquid is cooled to 55°C., and 5 ml of a 40% solution of benzyltrimethylammonium hydroxide dissolved in methanol is added over a 13 min. period. Heating is then continued at 55°C for 2 hrs. to form an ethylenically unsaturated isocyanurate.
• the resulting clear, emerald green solution is cooled to 55°C., and 1.5 ml of a 40% solution of benzyltrimethylammonium hydroxide in methanol is added. The solution remains unchanged for several minutes then begins to turn brown. The temperature of the solution is maintained at 55°C. until the isocyanate content falls to about 0.
• the resulting product is a styrene solution of the ethylenically unsaturated isocyanurate of toluene diisocyanate and hydroxypropyl methacrylate.
• Examples 3-5 are prepared according to the process recited in Example 2 except that the amounts of styrene, hydroxypropyl methacrylate (HPMA), hydroxyethyl methacrylate (HEMA), and toluene diisocyanate (TDI) used are those indicated in the following Table I
• Example 1 According to the process of Example 1, 1314 grams of styrene, 232 grams of hydroxypropyl methacrylate, 4 ml. of a 10% solution of tertiary butyl catechol in styrene, and 920 milligrams of cupric acetate monohydrate are heated to 90°C, under an air sparge and nitrogen blanket and 335 grams of toluene diisocyanate (25% excess) are then added slowly over 60 minutes. The temperature is maintained at 90°C during the addition and for 60 minutes afterward. The product is cooled to 41 °C. and 5 ml. of 4% benzyltrimethylammonium hydroxide (Triton B registered trade mark at least in the United Kingdom) in methanol are added.
• Triton B registered trade mark at least in the United Kingdom
• the temperature is maintained at 45°C for 4 hours.
• 5 ml. of tertiary butyl catechol (10% solution in styrene) and 1.05 ml. of methanesulfonic acid are added and the product is cooled.
• the resulting polymeric, ethylenically unsaturated polyisocyanurate contains a high proportion of product of molecular weight about 200,000 as determined by gel permeation chromatography.
• the viscosity after sitting overnight at room temperature is about 10,000 centipoise.
• a 3-liter, 4-neck flask equipped with temperature control, air sparge, N 2 blanket, condenser, addition funnel, and stirrer is charged with 1254 grams of styrene, 227 grams of hydroxypropyl methacrylate (hydroxyl number 364), 460 milligrams of cupric acetate monohydrate, and 4.0 ml. of 10% tertiary butyl catechol (TBC) in styrene.
• TBC tertiary butyl catechol
• the flask was then heated to 90°C. and 313 grams of toluene diisocyanate (TDI) is dripped in over a 55 minute period while the temperature is maintained at 90-98°C. At the end of the TDI addition the temperature is maintained at 90°C.
• TDI toluene diisocyanate
• Physical properties are measured on a 3 mm (1/8") casting that is postcured at 100°C. for 1 hour.
• the cure system comprises 100 grams resin, 0.4 gram dimethyl aniline, 0.5 gram cobalt naphthenate, 0.5 gram Lupersol 224 (registered trade mark at least in the United Kingdom) (acetylacetone peroxide solution), and 1.5 grams tertiary butyl perbenzoate.
• the casting (30% solids in styrene) has the following physical properties:
• a 3-liter, 4-neck flask equipped with mechanical stirrer, thermometer, air sparge, reflux condenser, and N 2 inlet is charged with 171.0 grams hydroxypropyl methacrylate (1.14 equiv.), 1315.8 grams styrene (12.64 equiv.), 0.4535 gram Cu(OAc) 2 . H 2 0, and 3.75 ml. 10% tertiary butyl catechol (TBC) in styrene solution and the mixture is heated while stirring to 90°C. 206.9 grams toluene diisocyanate (TDI) (1.19 equiv.) is added dropwise over a 1 hour period, while maintaining the . temperature at 90 ⁇ 5°C.
• TBC tertiary butyl catechol
• the reaction mixture is kept at 90 + 5°C. for an additional hour, then cooled over a 1 hour period to 35°C.
• the trimerization reaction is terminated after 2.6 hours by addition of 14.9 grams dibutylamine; after 15 minutes, 1.49 ml. methane-sulfonic acid (MSA) is added.
• MSA methane-sulfonic acid
• the resulting product has a viscosity of 998 cps. at 22.4°C.
• a 1/8" casting is made and cured according to the method described in Example 7.
• the casting (25% solids in styrene) has the following properties:
• methyl methacrylate (892 grams, 8.91 moles), hydroxypropyl methacrylate (414 grams, 2.78 moles), copper acetate monohydrate (0.403 gram), and 10% tertiary butyl catechol/styrene solution (4.0 cc.).
• methyl methacrylate 892 grams, 8.91 moles
• hydroxypropyl methacrylate 414 grams, 2.78 moles
• copper acetate monohydrate 0.03 gram
• 10% tertiary butyl catechol/styrene solution 4.0 cc.
• the mixture is stirred and heated to 90°C., and toluene diisocyanate (TDI) (468 grams, 2.69 moles) added slowly over two hours while maintaining the temperature at 90°C. After all the TDI is added, the temperature is maintained at 90°C.
• TDI toluene diisocyanate
• a 3 mm (1/8") laminate is prepared using two plies of 457 g/m 2 of 1-1/2 ounce) chopped fiberglass strand mat between two 0.25 mm (10 mil.) surfacing "C" glass mats and cured at 100°C. for one hour.
• the casting and laminate have the following properties:
• a 3-liter, 4-necked flask equipped with a mechanical stirrer, thermometer, air sparge, reflux condenser, dropping funnel and nitrogen inlet is charged with hydroxypropyl methacrylate (414 grams, 2.8 moles), styrene (772 grams, 7.4 moles), divinylbenzene (124 grams of a 72% active solution, 0.68 moles), cupric acetate monohydrate (0.45 gram), and 20% solution of tertiary butyl catechol in styrene (2 ml.).
• the mixture is heated to 40°C. and toluene diisocyanate (TDI) (80/20 mixture of 2,4- and 2,6-isomers, 486 grams, 2.8 moles) added over one hour.
• TDI toluene diisocyanate
• the reaction temperature is gradually increased to 90°C. by a combination of external heat and the exothermic nature of the reaction.
• the reaction mixture is kept at 90° for an additional hour and then cooled over ninety minutes to 45 ⁇ 5°C.
• Triton B 50% solution of benzyltrimethylammonium hydroxide in methanol, 5 ml.
• the reaction mixture is kept at 55 ⁇ 5°C. for 2.5 hours and the trimerization reaction terminated by addition of methanesulfonic acid (1.2 ml.).
• the product has a viscosity of 1060 cps. at 21°C.
• a laminate is prepared and cured according to the method used in Example 9. The cured laminate has a flexural strength of 130 MN/m 2 (18,800 psi) at room temperature and 76.5 MN/m 2 (11,100 psi) at 177°C (350°F).
• Example 1 The procedure and apparatus of Example 1 are used in Examples 11-17.
• the indicated amount of toluene diisocyanate is added dropwise under a nitrogen blanket and air sparge to the copper catalyst, t-butyl catechol, and unsaturated alcohol in styrene at about 90°C.
• the solution is cooled to about 55°C., Triton B added, and stirring is continued until the reaction is complete.
• the methanesulfonic acid and/or the TBC is then added to stabilize the product resin solution.
• the specific reactants, solvent, and catalysts used and the amounts thereof are shown in Table II.
• Examples 18-20 are prepared according to the process of Example 17 except that the indicated amounts of toluene diisocyanate, unsaturated alcohol, solvent and catalyst used are those indicated in Table III.
• Example 17 The procedure of Example 17 is used in Examples 21-26. The indicated reactants, catalysts and solvent and the amounts used are shown in Table IV.
• the isocyanurate products of Examples 27-34 are prepared according to the procedure of Example 1, except for the variations in reactants, solvent and catalysts indicated in Table V.
• a preferred method of preparing an isocyanurate composition of this invention containing allophanate groups is as follows.
• a chemical reactor equipped with agitator, condenser, gas pipe connections, vents and port holes is first flushed with subsurface nitrogen.
• an air sparge and nitrogen stream having relative flow rates of 1 to 3 are introduced into the reactor.
• 2.7 parts of hydroxypropylmethacrylate (HPMA) are then charged to the reactor.
• the air sparge and nitrogen streams are temporarily turned off and 0.0029 parts of copper acetate monohydrate and 0.012 parts of 20% solution of tertiary butyl catechol (TBC) in styrene are charged to the reactor under continuous agitation.
• TBC tertiary butyl catechol
• the air sparge and nitrogen blanket streams are turned on again and 5.7 parts of styrene are charged to the reactor.
• the reaction mixture is then heated to about 40°C.
• the incremental addition of an 80/20 mixture of 2,4- and 2,6-toluene diisocyanates (TDI) starts.
• An overall amount of 3.1 parts of TDI are charged over about one hour period.
• the exotherm of the reaction of TDI with the alcohol raises the temperature of the reaction mixture to about 90°C. If at the end of the TDI addition the temperature is lower or higher than 90° external heating or cooling is applied respectively to bring the temperature to about 90°C.
• the reaction mixture remains at about 90°C.
• the reaction product has a number average molecular weight of about 1160, a weight average molecular weight of about 2000, and a polydispersity of about 1.9.
• About 95% of the isocyanurates present have a molecular weight of below about 5200 and contain some isocyanurates having a molecular weight about 5200 and below about 26,000.
• This product has a ball and ring melting point of about 95°C. and a viscosity of about 400-600 cps at 25°C., and a refractive index of about 1.557N 2 g.
• the infra-red spectrum of this product shows absorption bands characteristic of isocyanurates and the essential absence of isocyanate functionality.
• the hydroxyl number of the product is essentially zero.
• the solution is maintained at 55°C for one hour.
• the reaction is terminated by the addition of 1.3 ml. of a 10% solution in styrene of a 50/50 mixture of t-butyl catechol and mono-methyl ether of hydroquinone.
• the product has a viscosity of 200 cps at 25°C.
• Two-ply glass laminates (25% glass, 3mm (0.125 inch) thick) of the resulting 50% resin solution in styrene and which are cured with 0.1% dimethylaniline, 0.5% acetylacetone peroxide solution (4% active oxygen), 1.5% tertiary butyl perbenzoate, and 0.1% of a 10% solution of tertiary butyl catechol in styrene, have the following physical properties measured at 150°C (300°F): flexural strength 121 MN/m 2 (17,600 psi); flexural modulus 3.31 x 10 3 MN/m 2 (0.48 x 10 6 psi); tensile strength 82 MN/m 2 (11,900 psi); tensile modulus 4.55 x 10 3 MN/ M 2 (0.66 x 10 6 psi); Barcol hardness 25-28; elongation 2.2%; notched Izod 5.5J (4.05).
• toluene diisocyanate 80/20 mixture of 2,4- and 2,6- isomers, 342 ml., 2.44 mole
• TDI toluene diisocyanate
• the product solidifies.
• the product is allowed to cool to 40°C. and then removed from the pan to be ground into a fine powder.
• the product is then dissolved in an equal weight of styrene. 1.5% tertiary butyl perbenzoate, 0.5% of a 6% solution of cobalt naphthenate, and 0.4% dimethylaniline are added and then 0.5% of acetylacetone peroxide solution (4% active oxygen) is added to the solution.
• the solution containing the curing reagents is used for the preparation of a 1/8" laminate containing about 25% glass.
• the physical properties of the laminate are as follows:
• This example illustrates the preparation of an allophanate-free resin from a resin containing a large amount of allophanate.
• a small reaction vessel is charged with 100 g. of a resin prepared according to Example 35, which by NMR analysis had an allophanate to urethane ratio of 0.45.
• 0.4 ml of Triton B (40% solution of benzyltrimethylammonium hydroxide in methanol) is added and 0.5 ml of a 10% solution of equal amounts of t-butylcatechol and the monomethyl ether of hydroquinone.
• the resulting mixture is heated for 1-1/2 hours at 95°C.
• the final product is free of all detectable allophanate linkages upon NMR analysis.
• a 500 ml, 3-necked flask equipped with mechanical stirrer, thermometer, air sparge, reflux condenser and dropping funnel is charged with 28.1 g. toluene diisocyanate (TDI) (80/20 mixture of 2,4- and 2,6-isomers) and 300 ml dry benzene.
• TDI toluene diisocyanate
• the mixture is heated to 55°C and 21.3 grams of hydroxypropyl methacrylate is added over a 6-minute period.
• the reaction mixture is kept at 55°C for an additional 16 minutes and then charged with 0.37 g. hydroquinone, 8.9 g.
• phenylisocyanate (0.07 moles) phenylisocyanate and 0.75 ml Triton B (40% solution of benzyltrimethylammonium hydroxide in methanol). Heating at 50°C is continued for 45 minutes. A white precipitate is formed and is removed by filtration. The precipitate is identified as an isocyanurate containing both phenyl and tolyl groups by IR analysis.
• a preferred method of preparing an allophanate-free isocyanurate composition of this invention is as follows: a 4-neck, round-bottom, 3-liter glass flask equipped with a thermometer, air and nitrogen inlet, dropping funnel and condenser is charged with 430 g. of hydroxypropyl methacrylate, 856 g. of styrene, 0.43 g. of cupric acetate monohydrate and 3.6 ml of a solution of t-butylcatechol in styrene. The solution is heated to 40°C and 426 g. of toluene diisocyanate added over 45 minutes. The temperature of the reaction medium during the addition of the toluene diisocyanate is allowed to gradually rise.
• the final temperature is 90°C.
• the temperature of the reaction mixture is kept at 90°C for a further 15 minutes.
• the resulting dark green liquid is cooled to 70°C and 2.8 ml of a 40% solution of benzyltrimethylammonium hydroxide dissolved in methanol is added in one lot.
• Methanesulfonic acid (1.33 ml) is then added, the reaction mixture cooled and 4.4 ml of a 10% solution of t-butylcatechol in styrene added.
• the NMR spectrum of the product does not contain allophanate proton signals at about 10.6 ppm.
• This resin has a stability to 1% benzoyl peroxide of at least 7 hours at room temperature.
• a 4-neck, round-bottom, 5 liter glass flask equipped with a thermometer, air and nitrogen inlet, dropping funnel and condenser is charged with 860 g. hydroxypropyl methacrylate, 1735 g. of styrene, 0.86 g. of cupric acetate monohydrate and 7.2 ml of a 10% solution of t-butylcatechol in styrene.
• the solution is heated to 41 °C and 876 g. of toluene diisocyanate added over 45 minutes.
• the temperature of the mixture is allowed to rise to 90°C gradually during the 45 minutes.
• the temperature of the reaction mixture is kept at 90°C for a further 15 minutes.
• the resulting dark green liquid is cooled to 67°C (over 37 minutes) and 10 mls of a 40% solution of benzyltrimethylammonium hydroxide dissolved in methanol added in one lot.
• the mixture is heated over 5 minutes to 70°C. After a further 5 minutes an exotherm to 94°C is observed. The exotherm is controlled by external cooling to 90°C and the mixture then held at 90°C for a further 131 minutes. 8.8 mls of a 10% solution of t-butylcatechol in styrene is added and the mixture cooled to 60°C.
• a 4-neck, round-bottom, 5-liter glass flask equipped with a thermometer, air and nitrogen inlet, dropping funnel and condenser is charged with 876 g. toluene diisocyanate, 1736 g. of styrene, 0.86 g. of cupric acetate monohydrate and 7.2 mls of a 10% solution of t-butylcatechol in styrene.
• the solution is heated to 40°C and 860 g. of hydroxypropyl methacrylate added over 45 minutes.
• the temperature of the mixture is allowed to rise to 90°C gradually during the 45 minutes.
• the temperature of the reaction mixture is kept at 90°C for a further 15 minutes.
• the resulting dark green liquid is cooled to 72°C over 30 minutes and 10 mls of a 40% solution of benzyltrimethylammonium hydroxide dissolved in methanol added in one lot. After 18 minutes at 71°C, an exotherm to 90.5°C over 5 minutes is observed.
• the reaction mixture is held at 90°C for 59 minutes and 2.66 mls of methanesulfonic acid added followed by 8.8 mls of a 10% solution of t-butylcatechol in styrene.
• the reaction mixture is then cooled to room temperature and stored.
• a 4-neck, round-bottom, 5-liter glass flask, equipped with a thermometer, air and nitrogen inlet, 2 dropping funnels and condenser is charged with 1736 g. of styrene, 0.86 g. of cupric acetate monohydrate and 7.2 mls of a 10% solution of t-butylcatechol in styrene.
• the solution is heated to 41 °C and 860 g. of hydroxypropyl methacrylate and 876 g. of toluene diisocyanate added simultaneously over 44 minutes.
• the temperature of the mixture is raised gradually to 90°C during the 45 minutes.
• a 3-!iter, 4-necked flask equipped with a mechanical stirrer, thermometer, air sparge, reflux condenser and dropping funnel is charged with hydroxypropyl methacrylate (441 g, 2.94 moles), styrene (954.9 g 915 moles) cupric acetate monohydrate (0.92 g) and 4 ml of a 10% solution of equal amounts of t-butyl catechol and the monomethyl ether of hydroquinone.
• the mixture is heated to 90°C and toluene diisocyanate (TDI) (80/20 mixture of 2,4 and 2,6 isomers, 496.2 g, 2.85 moles) added over 30 minutes.
• TDI toluene diisocyanate
• the reaction mixture is held at 90°C for 15 minutes and then cooled within 10 minutes to 65°C.
• Triton B 50% solution of benzyltrimethylammonium hydroxide in methanol, 5 ml
• the reaction mixture is stabilized with 2.5 ml of a 10% solution of equal amounts of t-butylcatechol and the monomethyl ether of hydroquinone.
• the trimerization reaction is terminated by the addition of methanesulfonic acid (1.5 ml). NMR analysis showed no detectable allophanate groupings.
• a 3-liter, 4-necked flask equipped with a mechanical stirrer, thermometer, air sparge, reflux condenser and dropping funnel is charged with hydroxypropyl methacrylate (441 g, 2.94 moles), styrene (954.9 g, 9.15 moles), cupric acetate monohydrate (0.92 g) and 4 ml of a 10% solution of equal amounts of t-butylcatechol and the moromethyl ether of hydroquinone.
• the mixture is heated to 90°C and toluene diisocyanate (TDI) (80/20 mixture) of 2,4 and 2,6-ixomers, 522.3 g, 3.00 moles) added over a one hour period.
• TDI toluene diisocyanate
• the reaction mixture is kept at 90°C for an additional hour and then cooled within 20 minutes to 55°C.
• Triton B 50% solution of benzyltrimethylammonium hydroxide in methanol, 5 ml
• the reaction is permitted to exotherm to 65°C. As the reaction proceeds it will cool slowly and heat is only applied to keep it at 55°C. After two hours holding the isocyanate peak has completely disappeared in the IR.
• the trimerization reaction is terminated by the addition of methanesulfonic acid (15 ml and stabilized by the addition of 5 ml of a 10% solution of equal amounts of t-butyl catechol and the monomethyl ether of hydroquinone.
• the product by NMR analysis shows an allophanate to urethane ratio of 0.1.

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• 1978
  • 1978-07-25 EP EP78300194A patent/EP0000659B1/en not_active Expired
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  • 1978-07-26 CA CA308,178A patent/CA1106533A/en not_active Expired
  • 1978-07-26 MX MX174318A patent/MX150030A/es unknown
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