MXPA00006994A - Optical resin composition - Google Patents

Abstract

Described is a polymerizable organic composition comprising an aromatic monomer having at least two vinyl groups, e.g., divinyl benzene, a polythiol monomer having at least two thiol groups, e.g., pentaerythritol tetrakis(2-mercaptoacetate), and an anhydride monomer having at least one ethylenically unsaturated group, e.g., methacrylic anhydride. Polymerizable compositions according to the present invention, may optionally further comprise a polymerizable comonomer having at least two (meth)acryloyl groups, e.g., pentaerythritol tetrakis(acrylate). Polymerizates prepared from polymerizable organic compositions of the present invention have a refractive index of at least 1.57 and an Abbe number of at least 33. Also described are photochromic articles prepared from such compositions.

Description

COMPOSITION OF OPTIC RESIN DESCRIPTION OF THE INVENTION The present invention relates to polymerizable and polymerized organic compositions having a refractive index of at least 1.57 and an Abbe number of at least 33, prepared from said compositions. More particularly, the present invention relates to certain polymerizable organic compositions comprising an aromatic monomer having at least two vinyl groups, a polythiol monomer and an anhydride monomer having at least one ethylenically unsaturated group. Numerous polymeric materials have been developed, for example, plastics, as alternatives and substitutes for glass in applications such as optical lenses, optical fibers, windows and transparencies for automotive, nautical and aviation. As used herein, the term "glass" is intended to refer to inorganic glasses based on silica. These polymeric materials can provide advantages with respect to glass, including, resistance to breakage, lighter weight for a given application, ease of molding and ease of dyeing. Representative examples of said polymeric materials include poly (methyl methacrylate), polycarbonate and poly (diethylene glycol bis (allyl carbonate)). The refractive indices of many materials are generally lower than those of the glasses. For example, the refractive index of poly (diethylene glycol bis (allyl carbonate)) is about 1.50, compared to that of high index glass, for example, from 1.60 to 1.80. When making lenses to correct a given degree of visual defect, for example, a correction for myopia, the use of a polymeric material having a lower refractive index will require finer lenses with respect to a material having an index of Higher refraction, for example, high index glass. If the degree of correction required is substantial, for example, in the case of severe myopia, lenses manufactured from a low index polymeric material can be made so thin as to negate any benefit of reduction in weight relative to a equivalent degree of correction obtained from a higher refractive index lens, for example, a high index glass lens. In addition, thick optical lenses are not aesthetically desirable. It is known that polymeric materials having refractive indices greater than 1.50 can be prepared from monomers containing halogens and / or sulfur atoms, for example, as described in U.S. Patent No. 5,484,872. . The materials from which lenses are manufactured, and in particular optical lenses, can be classified by their refractive indexes. As is known to those of ordinary skill in the art, low indices typically include refractive indices of less than 1.50 to 1.53; average indices comprising refractive indexes of 1.54 to 1.57; and high indices that commonly include refractive indices of 1.58 and above. Lenses prepared from polymeric materials having high refractive indices also typically have lower Abbe numbers (also known as nu values). The lower Abbe numbers are indicative of an increased level of chromatic dispersion, which typically manifests as an optical distortion at or near the edge of the lens. It is therefore consequently desirable to prepare transparent polymers, in particular optical lenses having a combination of a high refractive index and suitably high Abbe numbers, for example, preferably at least 33 and more preferably at least 35. It is further desirable that these polymeric materials they also possess physical properties, and in particular thermal properties, which are at least equivalent to and preferably better than those of the polymeric materials of lower indices. European Patent Publication No. 598,551 A2 discloses a crosslinkable polymer molding composition which includes an aromatic olefinic monomer, for example, divinyl benzene, and a di- or polythio compound, for example, tetrakis (3-mercaptopropionate) of pentaerythritol. The molding composition is described as further including a polymerizable comonomer selected from the group consisting of di-, tri-, tetra- and higher acrylates or methacrylates, for example, poly (ethylene glycol dimethacrylate). International patent publication WO 96/38486 discloses a crosslinkable polymer molding composition that includes an effective amount of an acrylic or meta-chiral monomer that provides high stiffness and a high number of Abbe to the final product, e.g., a diacrylate or methacrylate of tricyclodecane dimethanol, a di- or polythio compound, for example, tetrakis (3-mercaptopropionate) of pentaerythritol, a di- or polyvinyl monomer, for example, divinyl benzene and optionally a polymerizable comonomer, for example, an epoxidized monomer or oligomer . It has now surprisingly been found that substantially fully cured polymers prepared from polymerizable organic compositions of the present invention have a favorable balance of high refractive indices and suitably high Abbe numbers, and improved physical properties. According to the present invention, there is provided a polymerizable organic composition comprising: (a) an aromatic monomer having at least two vinyl groups, - (b) a polythiol monomer having at least two thiol groups; and (c) an anhydride monomer having at least one ethylenically unsaturated group. In accordance with the present invention, there is provided a polymerization of said polymerizable organic composition having a refractive index of at least 1.57, as determined in accordance with the American Standard Test Method (ASTM) number D542-95, and a Abbe number, that is, a nu value, of at least 33, as determined using an appropriate instrument, for example, a Bausch & Lomb ABBE-3L. In addition to the operative examples, or wherever indicated, it will be understood that all numbers expressing amounts of ingredients or reaction conditions used herein are modified in all cases by the expression "approximately".

DETAILED DESCRIPTION OF THE INVENTION The organic compositions of the present invention include an aromatic monomer, for example, substituted monocyclic and polycyclic aromatic hydrocarbons, having at least two vinyl groups. Examples of aromatic monomers that can be used in the polymerizable organic compositions of the present invention include, but are not limited to: divinyl benzene, eg, 1,2-divinyl benzene, 1,3-divinyl benzene, 1,4-divinyl benzene and mixtures of structural isomers of divinylbenzene; diisopropenyl benzene, for example, 1,2-diisopropenyl benzene, 1,3-diisopropenyl benzene, 1,4-diisopropenyl benzene and mixtures of structural isomers of diisopropenyl benzene; trivinyl benzene, for example, 1, 2, 4-trietenyl benzene, 1, 3, 5-trietenyl benzene and mixtures of structural isomers of trivinyl benzene; divinyl naphthalene, for example, 2,6-diethyl naphthalene, 1,7-diethyl naphthalene, 1,4-diethyl naphthalene and mixtures of structural isomers of divinyl naphthalene; halogen-substituted derivatives of divinyl benzene, diisopropenyl benzene, trivinyl benzene and divinyl naphthalene, for example, 2-chloro-1,4-diethyl benzene; and mixtures of said aromatic monomers. In a particularly preferred embodiment of the present invention, the aromatic monomer is divinylbenzene. According to the present invention, the aforesaid aromatic monomer is typically present in the polymerizable composition in an amount of at least 20% by weight, preferably at least 30% by weight, and more preferably at least 35% by weight, in based on the total weight of polymerizable organic composition. Also the aromatic monomer is typically prepared in the composition in an amount of not more than 80% by weight, preferably not more than 65% by weight, and more preferably not more than 50% by weight, based on the total weight of the composition. polymerizable organic composition. The aromatic monomer may be present in an amount comprised between any combination of these values, including the values quoted. The polymerizable organic compositions according to the present invention also comprise a polythiol monomer having at least two thiol groups. By "thiol group" is meant a -SH group which is capable of forming a covalent bond with an ethylenically unsaturated group, for example, a vinyl group. Without intending to be bound by any theory, it is thought that covalent bonds are formed between the thiol groups and the ethylenically unsaturated groups of the monomers of the present invention by means of a thiol-ene reaction mechanism, as is known to ordinary experts in the art. field. Examples of polythiol monomers suitable for use in the polymerizable organic compositions of the present invention include, but are not limited to, 2,2'-thiodi-ethanethiol, tetrakis (3-mercaptopropionate) of pentaerythritol, tetrakis (2-mercaptoacetate) of pentaerythritol, tris (3-mercaptopropionate) of trimethylolpropane, tris (2-mer-captoacetate) of trimethylolpropane, 4-mercaptomethyl-3,6-dithia-1,8-octanedithiol, 4-tert-butyl-l, 2-benzenedithiol , 4,4'-thiodibencenothiol, benzenedithiol, di (2-mercaptoacetate) of ethylene glycol, di (3-mercaptopropionate) of ethylene glycol, di (2-mercaptoacetate) of polyethylene glycol, di (3-mercaptopropionate) of polyethylene glycol and mixtures thereof. In a particularly preferred embodiment of the present invention, the polythiol monomer is selected from the group consisting of 2,2'-thiodiethanethiol, tetrakis (2-mercaptoacetate) of pentaerythritol, tetrakis (3-mercaptopropionate) of pentaerythritol and mixtures of said monomers. The polythiol monomer is typically present in the polymerizable organic compositions of the present invention in an amount of at least 20% by weight, preferably at least 30% by weight, and more preferably at least 40% by weight, based on total weight of the polymerizable organic composition. further, the polythiol monomer is typically present in the composition in an amount of not more than 60% by weight, preferably not more than 55% by weight, and more preferably not more than 50% by weight, based on the total weight of the composition. polymerizable organic composition. The amount of the polythiol monomer present in the composition can range between any combination of these values, including said values. In addition, an anhydride monomer having at least one ethylenically unsaturated group which is radically polymerizable is included in the polymerizable organic compositions of the present invention. Specific examples of suitable anhydride monomers include, but are not limited to, methacrylic anhydride, acrylic anhydride, maleic anhydride, 1-cyclopentene-1,2-dicarboxylic anhydride, itaconic anhydride and mixtures of such anhydride monomers. The anhydride monomer is typically present in the polymerizable organic compositions of the present invention in an amount of at least 3% by weight, preferably at least 6% by weight, and more preferably at least 10% by weight, based on the weight total of the polymerizable organic composition. Also, the anhydride monomer is typically present in the composition in an amount of not more than 40% by weight, preferably not more than 35% by weight, and more preferably not more than 30% by weight, based on the total weight of the composition. the polymerizable organic composition. The amount of anhydride monomer present in the composition can range between any combination of these values, including the values quoted. The polymerizable organic compositions according to the present invention may optionally include a radically polymerizable comonomer having at least two (meth) acryloyl groups. As used herein, the term "(meth) acrilollo" is intended to refer to both acryloyl and methacryloyl groups. The polymerizable comonomer may be selected from the group consisting of: (i) a monomer represented by the following general formula I, I O H2C: _ IcI_. (O. -CH-CH, 2) 'mm _0_.A-. (CH.-_. CH_0), -CH. where m and m are each a positive number, the sum of m and n being from 0 to 70, preferably from 2 to 40, and more preferably from 5 to 20, R3 and R4 are each hydrogen or methyl, R5 and R are each hydrogen or C 1 -C 2 alkyl, and A is a divalent linking group selected from the group consisting of straight or branched chain alkyl (usually containing from 1 to 8 carbon atoms), cyclic alkylene (usually from 5 to 8 carbon atoms) ), phenylene, phenylene substituted with C1-C9 alkyl, and a group represented by the following general formula II, II wherein, R7 and R8 are each alkyl CS-C4, chloro or bromo, p and q are each an integer from 0 to 4, represents a divalent benzene group or a divalent cydohexane group and X is 0, S, -S (0, -C (0) -, -CH, -, -CH = CH-, -C (CH3) 2-, -C (CH3) (C6HS) when it is the divalent benzene group, and X is O, S, -CH2-, or -C (CH3) 2- when it is the divalent cydohexane group; (ii) a bis [(meth) acryloyl-terminated] poly (ethylene glycol) monomer, which is different from comonomer (i), having a number average molecular weight of 200 to 2000 grams / mole; (iii) a poly (meth) acryloyl-terminated monomer represented by the following general formula III, III or R • - (O- (CH, _CH-_0).) 'R - where R' is a polyvalent radical of a polyol, and R4 and Rs have the same meaning as in general formula I, d is a number from 0 to 20, and j is an integer from 3 to 6, preferably from 3 to 4 and more preferably 3; and (iv) mixtures of polymerizable comonomers (i), (ii) and (iii). The polymerizable comonomer (i) represented by the general form-mule (I) can be prepared by methods that are well known in the art. One such commonly used method involves a two-step process, when the sum of m and n is greater than 0. In the first step, a polyol is reacted, for example, 4,4 '-isopropylidenediphenol, with a substance containing an oxirane, for example, ethylene oxide, propylene oxide, butylene oxide or butylene oxide, to form what is commonly referred to as an ethoxylated, propoxylated or butoxylated polyol having a hydroxyl functionality. In the second step, the ethoxylated, propoxylated or butoxylated polyol is esterified, or transesterifi ed, with an acid or ester-unsaturated such as methacrylic acid, an alkyl methacrylate, an acrylic acid, an alkyl acrylate, or a combination thereof. The second stage gives rise to the formation of the polymerizable comonomer represented by the general formula I. When the sum of m and n is 0, the polymerizable comonomer (i) can be prepared by esterification or transesterification of a polyol, for example, 4, 4 '-isopropylidenediphenol, with an acid or ester-unsaturated such as methacrylic acid, an alkyl methacrylate, an acrylic acid, an alkyl acrylate, or a combination thereof.

• - Examples of suitable polyols for use in the preparation of the polymerizable comonomer (i) represented by the general formula I, include, but are not limited to: straight chain alkylene glycols such as ethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, or diethylene glycol, triethylene glycol; branched chain alkylene glycols such as 1,2-propanediol, 2-methyl-1,3-propanediol, 1,2-butane diol, 1,3-butane diol, 2,3-butane diol; cyclic alkylene diols such as 1,2-cyclohexanol, 1,3-cyclohexanol and 1,4-cyclohexanol; phenylene diols such as ortho, meta and for dihydroxy benzene; alkyl substituted phenylene diols such as 2,6-dihydroxytoluene, 3-methylcatechol, 4-methylcatechol, 2-hydroxybenzyl alcohol, 3-hydroxybenzyl alcohol, and 4-hydroxybenzyl alcohol; dihydroxy-phenyl such as 4,4'-dihydroxybiphenyl and 2,2'-dihydroxybiphenyl; bisphenols such as 4,4'-isopropylidenediphenol; 4, 4'-oxybisphenol; 4,4'-dihydroxybenzophenone; 4, 4'-thiobisphenol; phenolphthalein; bis (4-hydroxyphenyl) methane; 4, 4 '- (1,2-ethanediyl) bisphenol; and 4, 4'-sulfonylbisphenol; halogenated bisphenols such as 4,4'-isopropylidenebis (2,6-dibromophenol), 4,4'-isopropylidenebis (2,6-dichlorophenol) and 4,4'-isopropylidenebis- (2, 3, 5, 6-tetrachlorophenol); and biscyclohexanols, which can be prepared by hydrogenation of the corresponding bisphenoles, such as 4,4'-isopropylidenebiscyclohexanol; 4,4'-oxybiscyclohexanol; 4, 4'-thiobiscyclohexanol; and bis (4-hydroxycyclohexanol) methane. In a preferred embodiment of the present invention, with reference to the general formulas I and II, X is -C (CH3) 2- , represents a divalent benzene group, p and q are each 0, R3 and R4 are each methyl, and the sum of m and n is - - from 5 to 20. The polymerizable comonomer (ii) is different from comonomer (i) and can be prepared as is known in the field from an esterification or transesterification reaction between poly (ethylene glycol) and an acid or ester -unsaturated such as methacrylic acid, an alkyl methacrylate, acrylic acid, an alkyl acrylate or a combination thereof. The bis [(meth) acryloyl-terminated] poly (ethylene glycol) comonomer preferably has a number average molecular weight of from 200 to 1200, more preferably from 500 to 700, grams / mole, as determined by gel exclusion chromatography. gel using a polystyrene pattern. A particularly preferred comonomer (ii) is a polyethylene glycol bismethacrylate, having an average molecular weight in the number of 600 grams / mole. The polymerizable comonomer (iii), as previously described with reference to general formula III, can be prepared by methods that are well known in the art. One such commonly used method involves a two-step process, when d is greater than 0. In the first step, a polyol, for example, trimethylolpropane, is reacted with a substance containing an oxirane, for example ethylene oxide, of propylene, -butylene oxide or -butylene oxide to form what is commonly referred to as an ethoxylated, propoxylated or butoxylated polyol having a hydroxyl functionality. In the second step, the ethoxylated, propoxylated or butoxylated polyol is esterified, or transesterified, with an acid or ester-unsaturated such as methacrylic acid, an alkyl methacrylate, acrylic acid, an alkyl acrylate or a combination of the same. The second step results in the formation of the copolymerizable monomer (iii). When d is 0, the comonomer (iii) can be prepared by esterification or transesterification of a polyol, for example, trimethylolpropane, with an acid or an unsaturated ester, such as methacrylic acid, a - - - unsaturated, such as methacrylic acid, an alkyl methacrylate, an acrylic acid, an alkyl acrylate, or a combination thereof. Examples of suitable polyols for use in the preparation of the polymerizable comonomer (iii) include, but are not limited to, glycerol, trimethylolpropane, 1, 3, 5-tris (2-hydroxyethyl) isocyanurate, di-trimethylolpropane, pentaerythritol and dipentaerythritol. A particularly preferred polymerizable comonomer (iii) can be defined with reference to general formula III where R 'is a pentaerythritol radical, d is 0, j is 3 or 4 and R 4 is hydrogen. As used herein, and with reference to general formula III, the phrase "R 'is a polyvalent radical of a polyol" is intended to refer to the polyvalent residue of the polyol used in the preparation of the polymerizable comonomer (iii). For example, in the case of pentaerythritol tetraacrylate (for which d is 0, j is four and R 4 is hydrogen) R 'is the tetravalent radical of pentaerythritol, that is, tetramethylene methane. In the case of trimethylolpropane triacrylate (for which d is 0, j is 3 and R 4 is hydrogen) R 'is the trivalent radical of trimethylolpropane, that is, 1,1,1-trimethylenepropane. When the polymerizable organic compositions of the present invention include polymerizable comonomer (s), the comonomer (s) is (are) typically present in an amount of at least 1% by weight, preferably at least 3% by weight, and more preferably at least 5% by weight, based on the total weight of said polymerizable organic composition. The polymerizable comonomer (s) may also be present in the composition in an amount of not more than 20% by weight, preferably not more than 15% by weight, and more preferably not more than 10% by weight, based on the total weight of the polymerizable organic composition. The amount of the optional polymerizable comonomer (s) is present in the composition can range between any combination of these values, including the cited values. The polymerization of the polymerizable organic composition of the present invention can be carried out by addition of the composition by adding to the composition an initiating amount of a material capable of generating free radicals, such as organic peroxy compounds or azobis (organonitrile) compounds, is, an initiator. Methods for polymerizing compositions having monomers containing radically polymerizable groups are well known to skilled artisans and any of the well-known techniques for polymerizing the polymerizable organic compositions described above can be used. Such polymerization methods include thermal polymerization, photopolymerization or a combination thereof. Examples of suitable organic peroxy compounds, which can be used as initiators of thermal polymerization include: esters of peroxymonocarbonate, such as peroxy-tert-butyl carbonate and 2-ethylhexyl, peroxy-tert-butyl carbonate and isopropyl; peroxycetales, such as l, l-di (t-butyl peroxy) -3,3,5-trimethylcyclohexane; esters of peroxydi-carbonate, such as di (2-ethylhexyl) peroxydicarbonate, di (sec-butyl) peroxydicarbonate and diisopropyl peroxydicarbonate; diacylperoxides, such as 2,4-dichlorobenzoyl peroxide, isobutyryl peroxide, decanoyl peroxide, lauroyl peroxide, propionyl peroxide, acetyl peroxide, benzoyl peroxide, p-chlorobenzoyl peroxide; peroxyesters such as t-butyl peroxypivalate, t-butyl peroxyoctylate, and t-butyl peroxyisobutyrate; methyl ethyl ketone peroxide and acetyl cyclohexanesulfonyl peroxide. Preferred thermal initiators are those that do not discolor the resulting polymer. A particularly preferred thermal initiator is 1,1-di- (t-butyl peroxy) -3,3,5-trimethylcyclohexane, which is commercially available from Nippon Oil and Fats Co., Ltd. under the trademark of PERHEXA® 3M. Examples of suitable azobis (organonitrile) compounds which can be used as thermal polymerization initiators include: azobis (isobutyronitrile) and azobis (2,4-dimethylvaleronitrile). The amount of thermal polymerization initiator used to initiate and polymerize the polymerizable organic compositions of the present invention may vary and will depend on the particular initiator used. Only the amount required to initiate and sustain the polymerization reaction, that is, an initiating amount, is required. With respect to the preferred peroxy compound, 1,1-di- (t-butyl peroxy) -3,3,5-trimethylcyclohexane, typically between 0.01 and 3.0 parts of that initiator can be used per 100 parts of monomers present in the polymerizable organic composition (phm). More usually, between 0.05 and 1.0 phm is used to initiate polymerization. Typically, the thermal curing cycle involves heating the polymerizable organic composition in the presence of the initiator from room temperature to 85 ° C to 130 ° C for a period of 2 hours to 30 hours. The photopolymerization of the polymerizable organic composition according to the present invention can be carried out in the presence of a photopolymerization initiator using ultraviolet light, visible light, or a combination thereof. Examples of suitable photopolymerization initiators include benzoin, benzoin methyl ether, benzoin isobutyl ether, benzophenone, acetophenone, 4,4'-dichlorobenzophenone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-isopropylthixthantone and 2,4,6-trimethylbenzoyldiphenylphosphine oxide. The amount of photopolymerization initiator used to initiate and polymerize the polymerizable organic compositions of the present invention varies and will depend on the particular initiator used. Only the amount required to initiate and sustain the polymerization reaction, that is, a start-up amount, is required. A preferred photopolymerization initiator is 2, 4,6-trimethylbenzoyldiphenylphosphine oxide. The photopolymerization initiator is typically used in an amount of 0.01% to 2% by weight, based on the total weight of the monomer components. The light source used for the photopolymerization is preferably selected from those that emit ultraviolet light. The light source is preferably a mercury lamp, a germicidal lamp or a xenon lamp. Visible light, for example sunlight, can also be used. The exposure time may differ depending, for example, on the wavelength and intensity of the light source and the mold configuration, and is typically determined empirically. The amount of thermal polymerization initiator or photopolymerization initiator and / or the consequent cure cycle will be suitable to produce a polymerization according to the present invention having a Barcol hardness at 15 seconds., of at least 1, preferably at least 4, for example, from 4 to 35. It will be understood that the polymerizable organic composition of the present invention can be polymerized in the absence of a polymerization initiator. In particular, the photopolymerization of the polymerizable organic composition of the present invention can be achieved in the absence of externally added thermal or photopolymerization initiators. Various conventional additives can be incorporated into the polymerizable organic composition of the present invention. Such additives may include light stabilizers, heat stabilizers, antioxidants, ultraviolet light absorbers, mold release agents, static (non-photochromic) dyes, pigments, polymerization initiators to promote stability during the storage, and absorbers of ultraviolet light. Also, anti-yellowing additives, for example, 3-methyl-2-butenol, organo pyrocarbonate and triphenyl phosphite [CAS 101-02-0], can be added to the polymerizable organic compositions of the present invention to improve resistance to yellowing. It is also contemplated that a moderator of the polymerization, or blends of moderators of the polymerization, may be added to the polymerizable organic composition of the present invention to minimize the formation of distortions, such as striations, in the polymerizations obtained therefrom. Suitable polymerization moderators include, for example, dilauryl thiodipropionate, terpinolene, l-isopropyl-4-methyl-1,4-cyclohexadiene, l-isopropyl-4-methyl-1,3-cyclohexadiene, -methylstyrene, 2-4. diphenyl-4-methyl-1-pentene, 1,1-diphenylethylene, cis-1,2-diphenylethylene, 2,6-dimethyl-2,4,6-octatriene, 4-tert-butylpyrocatechol and mixtures thereof. The moderator of the polymerization can be added to the polymerizable organic composition of the present invention in an amount of 0.01% to 10% by weight, preferably 0.1% to 8% by weight and more preferably 0.3% to 5% by weight, based on the total weight of the polymerizable organic composition. It is further contemplated that a flexibilizing additive may be added that does not have free radical polymerizable groups, hereinafter referred to as a non-polymerizable flexibilizing additive, to polymerize the organic compositions of the present invention. The non-polymerizable flexibilizing additive, or mixtures of nonpolymerizable flexibilizing additives, may be added in an amount of 0.05% to 15%, preferably from 0.5% to 10% and - more preferably from 2% to 6% by weight, based on the total weight of the monomers and the weight of additive (s) of non-polymerizable flexibilization (s). The non-polymerizable flexibilizing additive may be non-aromatic or aromatic. Examples of suitable nonpolymerizable flexibilization additives include alkoxylated phenol benzoate, alkoxylated naphthol benzoate, 1,3-bis (phenylthio) propane, bis (phenylthio) alkylene ether, the reaction product of phenyl chloroformate and dimercaptan, the product of reaction of dimercaptan and phosgene topped with phenol, cinnamates, triphenyl phosphite, tri (2-ethylhexyl) trimellitate, triisodecyl trimellitate, poly (alkylene glycol) dinaftoate, 2-ethylhexyl diphenylphosphate, isodecyl phosphate and diphenyl , tricresyl phosphate, poly (alkylene glycol) dibenzoates, for example, poly (ethylene glycol) dibenzoate and poly (propylene glycol) dibenzoate, esters of phthalic acid, isophthalic acid, and terephthalic acid, for example, dioctyl phthalate , and a member represented by the following general formula IV: IV H (0_CH_CH. -O-? 0__ (CH, _CH_ -0) £ .H where e and f are each a positive number, the sum of e and f being from 0 to 70, preferably from 2 to 40, and more preferably from 5 to 35, R5 and R6 are each hydrogen or Cx to C2 alkyl, preferably hydrogen or methyl and A has the same meaning as in general formula I. Examples of suitable polyols, for the preparation of non-polymerizable flexibilization additives represented by general formula IV where the sum of e and f is greater than 0, or for use as the additive non-polymerizable flexibilization where the sum of e and f is 0, include those described with respect to the first step of preparation of the polymerizable comonomer (i), exclusive of 4,4 '- (1,2-ethenediyl) bisphenol. A preferred non-polymerizable flexibilization additive can be defined with reference to general formula IV where the sum of e and f is from 25 to 35, Rs and R6 are each hydrogen, and A is a divalent linking group according to general formula II, where it represents a benzene-non-divalent group, p and q are each 0 and X is -C (CH3) 2-. Another preferred non-polymerizable flexibilization additive is poly (ethylene glycol) dibenzoate, which poly (ethylene glycol) precursor has a number average molecular weight of 100 to 1000 grams / mole. The polymerizates obtained from the polymerization of the polymerizable organic compositions of the present invention will be solid and transparent. The polymers of the present invention will also have a refractive index of at least 1.57, preferably at least 1.58 and more preferably at least 1.60, and suitably high Abbe numbers, for example, an Abbe number of minus 33 and preferably at least 35. The monomers that make up the polymerizable organic composition of the present invention, that is, the aromatic (a) monomers, (b) polythiol and (c) anhydride, are present in sufficient amounts to allow the preparation of a polymerization thereof, which has the characteristics listed above. For example, in a preferred embodiment of the present invention, the organic-polymerizable composition comprises from 42% to 48% by weight of the aromatic monomer, for example, divinyl benzene, from 42% to 48% by weight of the polythiol monomer, example, tetrakis (2-mercaptoacetate) of pentaerythritol, and 4% to 16% by weight of the anhydride monomer, for example, methacrylic anhydride, based entirely on the total weight of the composition. Solid articles that can be prepared from the polymerizable organic compositions of the present invention include, but are not limited to, optical lenses, such as flat and ophthalmic lenses, solar lenses, windows, automotive transparencies, eg, windshields, lights side and rear lights, and transparencies for aircraft, etc. When used to prepare photochromic articles, for example, lenses, the polymerized material will be transparent to that area of the electromagnetic spectrum that activates the photochromic substance (s) incorporated in the matrix, that is, to that wavelength of ultraviolet (UV) light that produces the colored or open form of the photochromic substance and that portion of the visible spectrum that includes the maximum absorption wavelength of the photochromic substance in its activated UV form, that is, the open The photochromic substances which can be used with the polymers of the present invention are organic photochromic compounds or substances which contain the same which can be incorporated, for example, dissolved, dispersed or diffused in said polymerizations. A first group of organic photochromic substances contemplated for use in the formation of photochromic articles of the present invention are those that have an activated absorption maximum within the visible range of more than 590 nanometers, for example, between more than 590 to 700 nanometers. These materials typically show a blue, bluish-green, or bluish-purple color when exposed to ultraviolet light in an appropriate solvent or matrix. Examples - of the classes of such substances that are useful in the present invention include, but are not limited to, spiro (indoline) naphthoxazines and spiro (indoline) benzoxazines. These and other classes of said photochromic substances are described in public literature. See, for example, U.S. Patent Nos .: 3,562,172; 3,578,602; 4,215,010; 4,342,668; 5,405,958; 4,637,698; 4,931,219; 4,816,584; 4,880,667; 4,818,096. See also, for example: Japanese Patent Publication 62/195383; and the text, Techniques in Chemistry, Volume III, "Photochromism", Chapter 3, Glenn H. Brown, Editor, John Wiley and Sons, Inc., New York, 1971. A second group of organic photochromic substances contemplated for use in forming the photochromic articles of the present invention are those that have at least one absorption maximum and preferably two absorption maxima, within the visible range of between 400 and less than 500 nanometers. These materials typically exhibit a yellow-orange color when exposed to ultraviolet light in an appropriate solvent or matrix. Such compounds include certain phenomena, for example, benzopyrans and naphthopirans. Many such phenomena are described in public literature, for example, U.S. Patents. 3,567,605; 4,826,977; 5,066,818; 4,826,977; 5,066,818; 5,466,398; 5,384,077; 5,238,931; and 5,274,132. A third group of organic photochromic substances contemplated for use in the formation of photochromic articles of the present invention are those that have an absorption maximum within the visible range of between 400 and 500 nanometers and another absorption maximum within the visible range of between 500 and 700 nanometers. These materials typically exhibit color (s) comprised between yellow / brown and purple / gray when exposed to ultraviolet light in an appropriate solvent or matrix. Examples of these substances include certain benzopyran compounds, which have substituents in the 2-position of the pyran ring and a substituted or unsubstituted heterocyclic ring, such as a benzothiene ring or benzofuran fused with the benzene portion of the benzopyran. Such materials are subject of U.S. Pat. No. 5,429,774. Other photochromic substances contemplated are photochromic organo-metalic dithizonets, that is, arylhydrazidates (arylazo) thioforms, for example, mercury dithytonates which are described in, for example, U.S. Pat. 3,361,706. Fulgados and fulgimides, for example, the 3-furyl and 3-thienyl fulgidae and fulgimides described in U.S. Pat. 4,931,220 in column 20, line 5 to column 21, line 38. Descriptions related to said photochromic substances in the patents cited above will be incorporated herein, in toto, by reference. The photochromic articles of the present invention may contain a photochromic substance or a mixture of photochromic substances, as desired. Mixtures of photochromic substances can be used to achieve certain activated colors such as almost neutral gray or brown. Each of the photochromic substances described herein can be used in amounts and in a ratio (when mixtures are used) such that the polymer to which the mixture of compounds is applied or to which they are incorporated shows the desired color, for example, a color substantially neutral such as shades of gray or brown when activated by unfiltered sunlight, that is, almost as neutral a color as possible gives the colors of the activated photochromic substances. The relative amounts of the aforementioned fo-tochromic substances will vary and will depend in part on the relative intensities of the color of the activated species of such compounds, and the desired final color. The photochromic compounds or substances described herein can be applied to or incorporated into the polymerized by various methods described in the art. Such methods include dissolving and dispersing the substance within the polymerized, for example, by imbibing the photochromic substance in the polymerized by immersing the polymerized in a hot solution of the photochromic substance or by thermal transfer; providing the photochromic substance as a separate layer between adjacent layers of the polymerized, for example, as a part of a polymeric film; and applying the photochromic substance as part of a coating placed on the polymerized surface. The term "imbibition" or "embed" is intended to mean and include the impregnation of the photochromic substance alone in the polymerization, absorption by solvent-assisted transfer of the photochromic substance into a porous polymer, vapor phase transfer, and others. such transfer mechanisms.

The amount of photochromic substance or composition containing the same that is applied or incorporated into the polymerized is not critical on the condition that a sufficient amount is used to produce a photochromic effect discernible to the naked eye upon activation. Generally, such an amount can be described as a photochromic amount. The particular amount used depends frequently on the intensity of color desired after irradiation thereof and on the method used to incorporate or apply the photochromic substances. Typically, the more photochromic substance applied or incorporated, the greater the intensity of color. In general, the amount of total photochromic substance incorporated into or applied to the photochromic optical polymer may range from 0.15 to 0.35 milligrams per square centimeter of area to which the (s) is applied or incorporated. ) photochromic substance (s). It is also contemplated that the photochromic substances may be added to the polymerizable organic compositions of the present invention prior to curing. However, when this is done, it is preferred that the photochromic substance (s) be (are) resistant to the potentially adverse interactions with the initiator (s). ) that can be present and / or the polythiol monomer and sulfide bonds that are formed within the polymerized. These adverse interactions can lead to the deactivation of the photochromic substance (s), for example, by trapping them either openly or closed. Such photochromic substances include photochromic pigments and organic photochromic substances encapsulated in metal oxides, the latter being described in U.S. Pat. 4,166,043 and 4,367,170. Organic photochromic substances sufficiently encapsulated within a matrix of an organic polymer can also be incorporated, as described in U.S. Pat. 4,931,220. in the polymerizable organic compositions of the present invention prior to curing. The present invention is described more particularly in the following examples, which are intended to be illustrative only, since numerous modifications and variations thereof will be apparent to those skilled in the art. Unless otherwise specified, all parts and percentages are by weight. EXAMPLES 1-7 Table 1 describes seven fo-topolymerizable monomer compositions. Examples 1, 2 and 3 are representative of embodiments of the present invention, which includes anhydride monomers having at least one ethylenically unsaturated group. Examples 4 to 7 are comparative examples.

- - TABLE 1 Example 1 2 3 4 5 6 7 Ingredients, Parts Monomer DVB a 45 45 45 45 45 45 45 Monomer PTMA b 45 45 45 45 45 45 45 Monomer MA c 10 0 0 0 0 0 0 Maleic anhydride 0 10 0 0 0 0 0 itaconic anhydride 0 0 10 0 0 0 0 PETRIA monomer d 0 0 0 10 0 0 0 DiPETHA monomer e 0 0 0 0 10 0 0 PETetraA monomer f 0 0 0 0 0 10 0 EGDMA monomer g 0 0 0 0 0 0 10 divinylbenzene monomer having a purity of 93% by weight. monomer tetrakis (2-mercaptoproacetate) pentaerythritol monomer methacrylic anhydride monomer pentaerythritol triacrylate monomer hexane acrylate dipentaerythritol monomer pentaerythritol tetraacrylate monomer ethylene glycol dimethacrylate monomer Molded sheets of the polymerizable monomer compositions of Table 1 were manufactured in the following manner. Each monomer composition was added to a suitable vessel and mixed using a magnetic stir plate and a magnetic stir bar at room temperature. The mixed monomer compositions were then poured into glass molds transmitting ultraviolet (UV) light having interior dimensions of 15.24 x 15.24 x 0.32 cm.

- - The contents of the filled molds were cured in the following manner. (1) A mold filled several times below a source of UV light was passed until it was observed by visual inspection that its contents had gelled. (2) Each side of the glass mold of 1524 x 15.24 cm was then passed four times below the UV light source. (3) The mold was then placed in an electric oven at 120 ° C for one hour. The UV light source used was a SYSTEMS® D-Bulb FUSION, which was placed at a distance of 15 cm (6 inches) above the glass molds. The glass molds were passed below the UV light source at a linear velocity of 91 cm (3 feet) / minute using a conveyor system model No. C636R commercially available from LESCO Inc. It was found that a single pass through under the UV light source as described, it imparted 4.9 joules / cm2 of UV energy inside the glass molds used. The physical properties of the molded sheets were measured and the results are summarized in Table 2. TABLE 2 Physical data Example 1 Physical test Distortion Temperature per ca- 65 75 61 lor (° C to 10 mils [254 microns]) h Total Bending Temperature (° C 130j 101 75 to 100 mils [2540 microns]) refractive index k 1.5990 1.6014 1.5994 (nD20) Abbe number? 35 34 34 - - Transmittance% m 91.7 91.1 91, 9 Haze% n 1.3 1.3 3.5 Density at 22 ° C (g / cc) 1,26 1,29 1,26 Conversion% ° 91,1 N. D.1 N.D.

TABLE 2 (continued) Physical data Example 4 Physical Test Distortion Temperature 44 39 37 45 by heat (° C to 10 milli-inches [254 microns]) h Bending Temperature 59 50 47 64 Total (° C to 100 mils [2540 microns]) 1 refractive index k 1.5996 1.5999 1.6000 1.5986 (nD20) Abbe number 35 34 33 34 Transmittance% m 91.5 91.6 91, 6 91.7 Haze% n 2.1 1.5 3.2 1.6 Density at 22 ° C (g / cc) 1.29 1.26 1.26 1.26 Conversion% 86.5 86.8 83.2 88 ,3 1 N.D. = Not determined h Heat Distortion Temperature, is the temperature at which the test sample was observed to have a flexion of 10 mils (254 microns), and was determined in accordance with ASTM D 648-95 using a Spot Apparatus of Softness Custom Scientific Instruments Model HDV3 DTUL / Vicat. 1 Total Bending Temperature is the temperature at which - - the test sample was observed to have a flexion of 100 mils (2540 microns), and was determined in accordance with ASTM D 648-95 using a Custom Reblanking Spot Apparatus. Scientific Instruments Model HDV3 DTUL / Vicat. 3 The Total Flexure Temperature value of Example 1 represents a flexion of 96.1 mils at a temperature of 130 ° C. k Refractive Index nD20 was determined in accordance with ASTM D542-95, using a Bausc & Refractometer; Lomb ABBE-3L. 1 The Abbe number (also known as nu value) was measured using a Bausch & Refractometer; Lomb ABBE-3L. m The Transmittance Percentage was determined in accordance with ASTM D 1003-95, using a HunterLab spectrophotometer model ColorQuest II. n The Haze Percentage was determined in accordance with ASTM D 1003-95 using a HunterLab spectrophotometer model ColorQuest II. ° The conversion rate of C = C double bonds in saturated C-C bonds was determined using a Mattson SIRUS 100 Fourier Transform Infrared (FTIR) instrument. A liquid sample of the uncured polymerizable organic composition was placed in a 2 millimeter (mm) thick quartz cell and the peak area was measured at a wavelength of 1.63 microns. The thickness and area of the peak were measured at a wavelength of 1.63 microns for a fully cured molded sheet corresponding to the liquid sample. The two types of measurements were used in the following equation to calculate the conversion percentage: 100 x. { [(area of the peak / mm) sample 1Igu.da - (area of the peak / mm) molded profile] / (area of the pi - EXAMPLES 8 and 9 Table 3 describes two compositions of thermally polymerizable monomers.Example 8 is representative • - an embodiment of the present invention, which includes methacrylic anhydride, Example 9 is a comparative example.

Example Example 8 9 Ingredients, Parts Monomer DVB at 45, 5 45, 5 Monomer PTMA b 45, 5 45, 5 Monomer MA c 9 0 Monomer EGDMA 9 0 9 Initiator LUPERSOL® 231 p 0 0,, 44 0, 4 p The LUPERSOL® 231 initiator is chemically 1,1- di (tert-butylperoxy) -3,3,5-trimethylcyclohexane, Chemical Abstracts No. (CAS No.) 6731-36-8, and is commercially available from Elf Atochem.

Molded sheets of the polymerizable compositions of Table 3 were manufactured in the following manner. Each monomer composition was transferred to a suitable vessel and the initiator LUPERSOL® 231 was added. The resultant initiated polymerizable monomer composition was mixed using a magnetic stir plate and a magnetic stir bar at 50 ° C. The mixed monomer compositions were then poured into glass molds having interior dimensions of 15.24 x 15.24 x 0.32 cm. The filled molds were thermally cured according to the thermal cure cycle detailed in Table 4. The physical properties of the molded sheets were measured and the results are summarized in Table 5.

- - TABLE 4 * Thermal cure cycle for Examples 9 and 10 Hours accumulated Oven temperature ° C 0 50 15 125 16 125 18,5 80 (end of cycle) * The temperature change rate represented in Table 4 was, in all cases, linear and continuous without any temperature maintenance. TABLE 5 Physical data Example Physical test Heat distortion temperature 102 87 (° C to 10 mils [254 microns]) Total distortion (mil) [m] 4 422 50 @ 130 ° C q [1067] [1270] Barcol hardness (0 seconds) r 43 42 Barcol hardness (15 seconds) r 41 39 refractive index k 1, 5973 1, 5974 (nD20) Abbe number 35 35 Transmittance% m 91 91 Density at 22 ° C (g / cc) ) 1, 262 1, 262 q Total Heat Distortion at 130 ° C, was determined in accordance with ASTM D 648-95 using a Custom Scientific Instruments Mulch Point Model HDV3 DTUL / Vicat. - - r The Barcol hardness was determined according to ASTM-D 2583-95, taking the scale readings immediately after the Barcol marking point entered in the sample and after 15 seconds. The data in Tables 2 and 5 show that the polymerizations obtained either by UV-curing or thermal-curing of the polymerizable monomer compositions of the present invention have improved thermal properties, that is, heat distortion temperature, coupled with high refractive indices and Abbe numbers, with respect to the comparative compositions of Examples 4 to 7 and 9. The percentage conversion data presented in Table 2 indicates that a higher conversion level of the C = C double bond can be obtained. with a polymerizable organic composition according to the present invention, ie, Example 1, with respect to comparative compositions, ie, Comparative Examples 4 to 7. The present invention has been described with respect to specific details of particular embodiments of the same. It is not intended that said details be considered limitations on the scope of the invention except to the extent and extent that they are included in the appended claims.

Claims (20)

- - Claims
1. A polymerizable organic composition comprising: (a) an aromatic monomer having at least two vinyol groups; (b) a polythiol monomer having at least two thiol groups, And (c) an anhydride monomer having at least one ethylenically unsaturated group, with the proviso that a polymerizate of said polymerizable organic composition has a refractive index of at least 1.57 and an Abbe number of at least 33.
2. 2. The polymerizable organic composition of claim 1 wherein said aromatic monomer is selected from the group consisting of divinyl benzene, diisopropenyl benzene, trivinyl benzene, divinyl naphthalene, divinyl benzene derivatives substituted with halogen, diisopropenyl benzene, tri-vinyl benzene and divinyl naphthalene, and mixtures thereof.
3. 3. The polymerizable organic composition of claim 2, wherein said aromatic monomer is divinyl benzene.
4. 4. The polymerizable organic composition of claim 1 wherein said polythiol monomer is selected from the group consisting of 2,2'-thiodiethanethiol, tetrakis (3-mercaptopropionate) of pentaerythritol, tetrakis (2-mercaptoacetate) of pentaerythritol, tris (3-mercaptopropionate) of trimethylolpropane, trimethylolpropane tris (2-mercaptoacetate), 4-mercaptomethyl-3,6-dithia-l, 8-octanedithiol, 4-tert-butyl-1,2-benzenedithiol, 4,4'-thiodibenzenethiol, benzenedithiol , di (2-mercaptoacetate) of ethylene glycol, di (3-mercaptopropionate) of ethylene glycol, di (2-mercaptoacetate) of poly (ethylene glycol), di (3-mercapto-propionate) of poly (ethylene glycol) and mixtures of such polythiol monomers.
5. 5. The polymerizable organic composition of claim 1, wherein said anhydride monomer is selected from the group consisting of methacrylic anhydride, acrylic anhydride, maleic anhydride, 1-cyclopentene-1, 2-dicarboxylic anhydride, itaconic anhydride and mixtures thereof.
6. 6. The polymerizable organic composition of claim 1, wherein said aromatic monomer is present in an amount of between 20% and 80% by weight, based on the total weight of said polymerizable organic composition, said polythiol monomer is present in an amount of between 20 and 80% by weight. % and 60% by weight, based on the total weight of said polymerizable organic composition, and said anhydride monomer is present in an amount of between 3% and 40% by weight, based on the total weight of said polymerizable organic composition.
7. 7. The polymerizable organic composition of claim 5 wherein said anhydride monomer is methacrylic anhydride.
8. 8. The polymerizable organic composition of claim 7 wherein said aromatic monomer is divinyl benzene and said polythiol monomer is selected from the group consisting of 2,2'-thiodiethanethiol, pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (2-mercaptoacetate) and mixtures of such polythiol monomers.
9. 9. The polymerizable organic composition of claim 8 wherein the divinyl benzene is present in an amount of between 30% and 65% by weight, based on the total weight of said polymerizable organic composition, said polythiol monomer being present in an amount of between 30% and 55% by weight, based on the total weight of said polymerizable organic composition, and the methacrylic anhydride is present in an amount between 6% and 35% by weight, based on the total weight of said polymerizable organic composition.
10. 10. The polymerizable organic composition of claim 1 further comprising a radically polymerizable comonomer having at least two (meth) acryloyl groups.
11. 11. The polymerizable organic composition of claim 10 wherein said radically polymerizable comonomer is selected from the group consisting of: (i) a monomer represented by the following general formula, o o H2 C ^ C _ IcCI_ (0_CH-CH2) m _0_A_0- (CH2 _CH_0) n -C C CH2 where m and m are each a positive number, the sum of m and n being from 0 to 70, R3 and R4 are each hydrogen or methyl, R5 and R6 are each hydrogen or alkyl Cj ^ - ,, and A is a linking group divalent selected from the group consisting of linear or branched chain alkylene, cyclic alkylene, phenylene, phenylene substituted with alkyl and a group represented by the following general formula, < R7 > p (R «), - - where, R7 and Ra are each alkyl ^ d, chloro or bromo, p and q are each an integer from 0 to 4, represents a divalent benzene group or a divalent cydohexane group and X is O, -S (0 -C (0) -CH, -CH = CH-, -C (CH 3) 2-, -C (CH 3) (C, HS) or when it is the divalent benzene group, and X is O, S, -CH, or -C (CH3) 2- when it is the divalent cydohexane group; (ii) a bis [(meth) acryloyl-terminated] poly (ethylene glycol) monomer, which is different from comonomer (i), having a number average molecular weight of 200 to 2000 grams / mole; (iii) a poly (meth) acryloyl-terminated monomer represented by the following general formula, R '- (0_ (CH, -CH_0) d-C_ -C ^ CH,). R- where R 'is a polyvalent radical of a polyol, and R4 is hydrogen or methyl, R5 is hydrogen or alkyl Cx to C2, d is a number from 0 to 20, and j is an integer from 3 to 6; and (iv) mixtures of polymerizable comonomers (i), (ii) and (iii).
12. 12. The polymerizable organic composition of the reivin- - - 11 wherein X is -C (CH 3) 2 - represents a divalent benzene group, p and q are each 0, R 3 and R 4 are each methyl, the sum of m and n is between 0 and 20, R 'is a pentaerythritol radical , j is 3 and d is 0.
13. 13. The polymerizable organic composition of claim 12 wherein said radically polymerizable comonomer is monomer (iii) and is present in an amount of between 1% and 20% by weight, based on the total weight of said polymerizable organic composition.
14. 14. The polymerization of claim 1.
15. 15. The polymerization of claim 9.
16. 16. The polymerization of claim 11
17. 17. A photochromic article comprising: (a) the polymerization of claim 1, and (b) a photochromic amount of a photochromic organic substance.
18. 18. A photochromic article comprising: (a) the polymer of claim 9, and (b) a photochromic amount of a photochromic organic substance.
19. 19. The photochromic article of claim 18 wherein the photochromic organic substance is selected from the group consisting of spiro (indoline) naphthoxazines, spiro (indoline) benzoxazines, benzopyrans, naphthopyrans, crome- - nos, organo-metal dithynates, fulgides and fulgimides and mixtures of such photochromic organic substances.
20. 20. A photochromic article comprising: (a) The polymerizate of claim 11; and (b) a photochromic amount of a photochromic organic substance.