Organic polymerizable compositions, polymerizates and optical articles formed therefrom, and methods of reducing opacity in optical articles

Abstract

The present disclosure is directed to an organic polymerizable composition, and polymerizates and optical articles prepared therefrom. The composition comprises: (a) an isocyanate-functional prepolymer and (b) an aromatic diamine having at least one primary amino group. The prepolymer (a) is prepared from a reaction mixture comprising: (i) a polyisocyanate component comprising (1) an aliphatic polyisocyanate having at least one primary and at least one secondary isocyanate functional group; and (2) 4,4'-methylenebis(cyclohexyl isocyanate); and (ii) a polyol component. The composition further comprises a photochromic compound, which may be present in the reaction mixture forming the prepolymer. Methods of reducing opacity in optical articles are also provided.

Description

ORGANIC POLYMERIZABLE COMPOSITIONS, POLYMERIZATES AND OPTICAL ARTICLES FORMED THEREFROM, AND METHODS OF REDUCING OPACITY IN OPTICAL ARTICLESFIELD OF THE DISCLOSURE

[0001] The present disclosure provides organic polymerizable compositions, polymerizates formed from the organic polymerizable compositions, and optical articles formed from the polymerizates. The present disclosure also provides methods of reducing opacity in optical articles.BACKGROUND

[0002] The use of various thermosetting organic polymeric compositions are known in the art for use in the production of polymerizates and molded polymeric articles. When such molded polymeric articles include polymeric optical articles, the compositions must provide optical articles having acceptable optical qualities while maintaining durability and impact resistance. Examples of such molded polymeric optical articles can include windshields, sunglasses, fashion lenses, non-prescription and prescription lenses, sport masks, face shields, components of augmented reality, virtual reality, mixed reality, or smart eyewear, and goggles.

[0003] A number of organic polymeric materials, such as plastics, have been developed as alternatives and replacements for glass in applications, such as optical lenses, fiber optics, windows and automotive, nautical and aviation transparencies. These polymeric materials can provide advantages relative to glass, including shatter resistance, lighter weight for a given application, ease of molding and demolding, and ease of dyeing or imparting a color or tint. However, haze and increased opacity may result in the molded polymerizate, particularly when incompatible components (i. e., components that do not form a homogeneous mixture) are used together in the reaction mixture. Haze may be defined as the percentage of incident light scattered by more than 2.5 degrees through a glass or plastic specimen. Haze is often measured in the art at 550 nanometers using, for example, a Haze Gard Plus Instrument available from BYK-Gardner, in accordance with ASTM D-1003 (published 2003). Alternatively, non-homogeneity due to incompatibility of components may manifest itself in the form of a milky appearance (opacity), especially in tinted or darkenedarticles. In such cases, a measurement of opacity (usually reported as a percent) at high thicknesses (such as 8 mm or 12 mm) can serve as a means of quantifying the optical phenomenon in the articles.

[0004] There is a need in the art to develop a polymerizable composition that does not develop opacity during casting and polymerizing, while maintaining other expected optical properties, such that the final article is of acceptable optical quality.SUMMARY OF THE DISCLOSURE

[0005] The present disclosure is directed to an organic polymerizable composition, and polymerizates and optical articles prepared therefrom. The composition comprises: (a) an isocyanate-functional prepolymer and (b) an aromatic diamine having at least one primary amino group. The prepolymer (a) is prepared from a reaction mixture comprising: (i) a polyisocyanate component comprising (1 ) an aliphatic polyisocyanate having at least one primary and at least one secondary isocyanate functional group; and (2) 4,4'-methylenebis(cyclohexyl isocyanate); and (ii) a polyol component comprising a di- and / or tri-functional polyol having a calculated hydroxyl equivalent weight of 150 to 2500 grams / equivalent, or 200 to 2500 grams / equivalent, or 150 to 2000 grams / equivalent, or 200 to 2000 grams / equivalent. The composition further comprises a photochromic compound, in the reaction mixture used to prepare the prepolymer (a) and / or in the organic polymerizable composition as a third component (c).

[0006] Methods of reducing opacity in optical articles are also provided. An exemplary method comprises (a) preparing an isocyanate-functional prepolymer by reacting together a reaction mixture comprising: (i) a polyisocyanate component comprising (1 ) an aliphatic polyisocyanate having at least one primary and at least one secondary isocyanate functional group; and (2) 4,4'-methylenebis(cyclohexyl isocyanate), wherein the equivalent ratio of isocyanate-functional groups in the aliphatic polyisocyanate (1 ) to isocyanate-functional groups in the 4,4'- methylenebis(cyclohexyl isocyanate) (2) is from 1 :8 to 5:1 , or from 1 :7.5 to 4.75:1 ; and (ii) a polyol component comprising a di- and / or tri-functional polyol having a calculated hydroxyl equivalent weight of 150 to 2500 grams / equivalent, or 200 to 2500 grams / equivalent, or 150 to 2000 grams / equivalent, or 200 to 2000 grams / equivalent; (b) reacting the prepolymer formed in (a) with an aromatic diamine, in the presence ofa photochromic compound to form a polymerizate; and (c) forming an optical article from the polymerizate. Opacity is reduced compared to optical articles not prepared by this method; for example, by not using a polyisocyanate component comprising (1 ) an aliphatic polyisocyanate having at least one primary and at least one secondary isocyanate functional group in the reaction mixture; or by not using (2) 4,4'- methylenebis(cyclohexyl isocyanate) in the reaction mixture; or wherein the equivalent ratio of isocyanate-functional groups in the aliphatic polyisocyanate (1 ) to isocyanate- functional groups in the 4,4'-methylenebis(cyclohexyl isocyanate) (2) is not from 1 :8 to 5:1 ; or by not using (ii) a polyol component comprising a di- and / or tri-functional polyol having a calculated hydroxyl equivalent weight of 150 to 2500 grams / equivalent, or 200 to 2500 grams / equivalent, or 150 to 2000 grams / equivalent, or 200 to 2000 grams / equivalent in the reaction mixture; or by not (b) reacting the prepolymer formed in (a) with an aromatic diamine, in the presence of a photochromic compound to form a polymerizate.

[0007] Additionally or alternatively, at least one photochromic compound containing a functional group that is reactive with the polyisocyanate component (i) may be included in the reaction mixture used to prepare the isocyanate-functional prepolymer.DETAILED DESCRIPTION

[0008] It is noted that, as used in this specification and the appended claims, the singular forms “a”, “an”, and “the” include plural referents, unless expressly and unequivocally limited to one referent.

[0009] For the purposes of this specification, unless otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions, and other parameters used in the specification and claims are to be understood as being modified in all instances by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties to be obtained by the disclosed composition. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0010] All numerical ranges herein include all numerical values and ranges of all numerical values within the recited numerical ranges. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0011] The various examples presented herein are each understood to be nonlimiting with respect to the scope of the disclosure.

[0012] As previously mentioned, the present disclosure is directed to an organic polymerizable composition, and polymerizates and optical articles prepared therefrom. The term "optical quality", as used for example in connection with polymeric materials, e.g., a "resin of optical quality" or "organic polymeric material of optical quality" means that the indicated material, e.g., a polymeric material, resin, or resin composition, is or forms a substrate, layer, film or coating that can be used as an optical article, such as a lens, or in combination with an optical article.

[0013] The term "optical article" means that the specified article exhibits a light transmittance value (transmits incident light) of at least 4 percent, such as at least 50 percent, or at least 70 percent, or at least 85 percent. As used herein, optical articles may demonstrate a light transmittance (% Transmittance, as defined by Equation 1 below , where I is the light transmitted through the article and Io is the incident light) of at least 70% when measured at 550 nanometers by, for example, a Hunter UltraScan PRO (Hunter Associates Laboratory, Inc.) using D65 illuminant.Equation 1 . % Transmittance = 100 x I / Io

[0014] The term "optical article " further means that the specified article exhibits a haze value of less than 5 percent, e.g., less than 1 percent or less than 0.5 percent, when the haze value is measured at 550 nanometers by, for example, a Haze Gard Plus Instrument, available from BYK-Gardner. Optical articles include, but are not limited to, lenses, optical layers, e.g., optical resin layers, optical films and optical coatings, and optical substrates having a light influencing property. As noted above, non-homogeneity due to incompatibility of components may manifest itself in the form of a milky appearance (“opacity”), especially in tinted or darkened articles (ex. sun lenses, polarized lenses, etc.) and becomes more apparent as the thickness of thearticle increases. In such cases, measurement of opacity at a constant thickness using an opacimeter or spectrophotometer can serve as a means of quantifying the phenomenon. Opacity is usually determined by one or more measurements of reflectance of visible light through an article. For example, opacity may be calculated from a ratio of diffuse reflectance measurements of the article with a black backing and the article with a white backing. The optical articles of this disclosure typically exhibit an opacity value of less than 28 percent, e.g., less than 27 percent, when the opacity value is measured, for example, using an EEL 12M Opacimeter, available from Smithers, or an Ultra Scan PRO spectrophotometer, available from HunterLab, at an article thickness of 8 mm, or an opacity value of less than 51 percent, e.g., less than 50 percent, when the opacity value is measured, for example, using an EEL 12M Opacimeter, available from Smithers, or an Ultra Scan VIS spectrophotometer, available from HunterLab, at an article thickness of 12 mm.

[0015] The organic polymerizable composition as disclosed herein comprises (a) an isocyanate-functional prepolymer. The prepolymer (a) is prepared from a reaction mixture comprising: (i) a polyisocyanate component; and (ii) a polyol component. The polyisocyanate component (i) comprises: (1 ) an aliphatic polyisocyanate having at least one primary and at least one secondary isocyanate functional group; and (2) 4,4'-methylenebis(cyclohexyl isocyanate). It has been found that the use of the asymmetric aliphatic polyisocyanate (1 ) having at least one secondary isocyanate functional group in combination with the 4,4'- methylenebis(cyclohexyl isocyanate) (2) described below, in specific equivalent ratios, unexpectedly contributes significantly to a reduction in opacity of the polymerizate, particularly when additive components such as colorants or dyes, including photochromic dyes, thermochromic dyes, electrochromic dyes, and the like are included that may have compatibility difficulties.

[0016] Suitable aliphatic polyisocyanates (1 ) having at least one primary and at least one secondary isocyanate functional group include isophorone diisocyanate. Other such aliphatic polyisocyanates having at least one primary and at least one secondary isocyanate functional group are also suitable. As used herein, the terms “aliphatic and cycloaliphatic polyisocyanates” refer to compounds having 6 to 100 carbon atoms linked in a straight chain or cyclized having two or more isocyanate reactive groups.

[0017] The aliphatic polyisocyanate (1 ) is typically present in the polyisocyanate component (i) in an amount of at least 10 percent by weight, or at least 20 percent by weight, or at least 30 percent by weight, or at least 40 percent by weight, and at most 80 percent by weight, or at most 70 percent by weight, or at most 60 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the 4,4'- methylenebis(cyclohexyl isocyanate) (2). For example, the aliphatic polyisocyanate (1 ) may be present in the polyisocyanate component (i) in an amount of 10 to 80 percent by weight, or 20 to 80 percent by weight, or 30 to 80 percent by weight, or 40 to 80 percent by weight, or 10 to 70 percent by weight, or 20 to 70 percent by weight, or 30 to 70 percent by weight, or 40 to 70 percent by weight, or 10 to 60 percent by weight, or 20 to 60 percent by weight, or 30 to 60 percent by weight, or 40 to 60 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the 4,4'- methylenebis(cyclohexyl isocyanate) (2).

[0018] The polyisocyanate component (i) further comprises (2) 4,4'- methylenebis(cyclohexyl isocyanate), also called dicyclohexylmethane-4,4’- diisocyanate, 4,4'-diisocyanato-methylenedicyclohexane, 4,4'-HMDI, or bis(4- isocyanatocyclohexyl)methane. The 4,4'-methylenebis(cyclohexyl isocyanate) (2) often comprises an isomeric mixture thereof. As used herein and the claims, the term “isomeric mixtures” refers to a mixture of at least two of the cis-cis, trans-trans, and cis-trans isomers of the polyisocyanate. Non-limiting examples of isomeric mixtures can include the trans-trans isomer of 4,4'-methylenebis(cyclohexyl isocyanate), hereinafter referred to as "PICM" (paraisocyanato cyclohexylmethane), and one or both of the cis-trans isomer of PICM and the cis-cis isomer of PICM.

[0019] Non-limiting examples of suitable commercial sources include VESTANAT® H12MDI (available from Evonik) and DESMODUR® W (available from Covestro).

[0020] The equivalent ratio of isocyanate-functional groups in the aliphatic polyisocyanate (1 ) to isocyanate-functional groups in the 4,4'-methylenebis(cyclohexyl isocyanate) (2) typically ranges from 1 :8 to 5:1 , such as from 1 :7.5 to 4.75:1 . In specific examples when the aliphatic polyisocyanate (1 ) is isophorone diisocyanate, the weight ratio of the isophorone diisocyanate to the 4,4'-methylenebis(cyclohexyl isocyanate) (2) may range from 10:90, or 20:80, or 30:70, or 40:60 to 80:20, or 75:25, or 70:30. For example, the weight ratio of the isophorone diisocyanate to the 4,4'-methylenebis(cyclohexyl isocyanate) (2) may range from 10:90 to 80:20 (i. e., 10 to 80 parts by weight isophorone diisocyanate:90 to 20 parts by weight 4,4'- methylenebis(cyclohexyl isocyanate) (2)), or 20:80 to 80:20, or 30:70 to 80:20, or 40:60 to 80:20, or 10:90 to 75:25, or 20:80 to 75:25, or 30:70 to 75:25, or 40:60 to 75:25, or 10:90 to 70:30, or 20:80 to 70:30, or 30:70 to 70:30, or 40:60 to 70:30.

[0021] The equivalent ratio of the polyisocyanate (1 ) to the 4,4'- methylenebis(cyclohexyl isocyanate) (2) may range from 1 :8, or 1 :6, or 1 :4, or 1 :1 to 5:1 , or 4:1 , or 3:1. For example, the equivalent ratio of the polyisocyanate (1 ) to the 4,4'-methylenebis(cyclohexyl isocyanate) (2) may range from 1 :8 to 5:1 (i. e., 1 to 5 equivalents polyisocyanate (1 ):8 to 1 equivalents 4,4'-methylenebis(cyclohexyl isocyanate) (2)), or 1 :6 to 5:1 , or 1 :4 to 5:1 , or 1 :1 to 5:1 , or 1 :8 to 4:1 , or 1 :6 to 4:1 , or 1 :4 to 4:1 , or 1 :1 to 4:1 , or 1 :8 to 3:1 , or 1 :6 to 3:1 , or 1 :4 to 3:1 , or 1 :1 to 3:1 .

[0022] The polyisocyanate component (i) may further comprise one or more additional polyisocyanates different from (1 ) and (2). Additional diisocyanates that can be used include hexamethylene diisocyanate, diphenylmethane-4,4’-diisocyanate, m- xylylene diisocyanate (“MXDI”), and meta-tetramethylxylylene diisocyanate (1 ,3-bis( 1 - isocyanato-1 -methylethyl)-benzene) which is commercially available from Cytec Industries Inc. under the trade name TMXDI® (Meta) Aliphatic Isocyanate.

[0023] The polyol component (ii) used to prepare the prepolymer (a) comprises a di- and / or tri-functional polyol having a calculated hydroxyl equivalent weight of 150 to 2500 grams / equivalent, or 200 to 2500 grams / equivalent, or 150 to 2000 grams / equivalent, or 200 to 2000 grams / equivalent. Hydroxyl equivalent weight may be derived from a calculated or measured molecular weight. Number average molecular weights (Mn) may be determined by nuclear magnetic resonance (NMR) spectroscopy, as is well known to those skilled in the art. End group analysis using NMR spectroscopy has long been established as a viable analytical technique for determining the number average molecular weight of compounds.

[0024] The polyol component (ii) used to prepare the prepolymer (a) often comprises a polyester polyol. Such polyols may be prepared in a known manner by condensation of polyhydric alcohols and polycarboxylic acids. Exemplary polyhydric alcohols include, but are not limited to, ethylene glycol, propylene glycol, butylene glycol, 1 ,6-hexylene glycol, neopentyl glycol, diethylene glycol, glycerol, trimethylol propane, and pentaerythritol. Suitable polycarboxylic acids may include succinic acid,adipic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, and trimellitic acid. Besides the polycarboxylic acids mentioned above, functional equivalents of the acids such as anhydrides where they exist or lower alkyl esters of the acids such as the methyl esters may be used.

[0025] In certain examples, the polyol component (ii) comprises at least one polyester polyol derived from a lactone, such as a-acetolactone, [3-propiolactone, y- butyrolactone, 6-valerolactone, and epsilon-caprolactone. In particular examples, the polyol component (ii) may comprise at least one polyester polyol derived from caprolactone, such as a mixture of up to four different polyester polyols derived from caprolactone. Particularly suitable polyester polyols include reaction products of epsilon-caprolactone with one or more polyols, usually diols, that typically contain from 2 to 16, or from 2 to 10, or from 2 to 6 carbon atoms. Non-limiting examples of glycols and other such polyols can include ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, 1 ,2-, 1 ,3- and 1 ,4-butanediol, 2,2,4-trimethyl-1 ,3-pentanediol, 2-methyl-1 ,3-pentanediol, 1 ,3- 2,4- and 1 ,5-pentanediol, 2,5- and 1 ,6-hexanediol, 2,4-heptanediol, 2-ethyl-1 ,3- hexanediol, 2,2-dimethyl-1 ,3-propanediol, 1 ,8-octanediol, 1 ,9-nonanediol, 1 ,10- decanediol, 1 ,4-cyclohexanediol, 1 ,4-cyclohexanedimethanol, 1 ,2-bis(hydroxyethyl)- cyclohexane, glycerin, trimethylolethane and trimethylolpropane; and isomers thereof. A polyester polyol may be prepared by condensing caprolactone in the presence of a difunctional active hydrogen compound, such as water, or at least one of the diols listed above. For example, polyester polyols for use in the preparation of the prepolymer (a) can be prepared using known esterification or transesterification procedures as described, for example, in the article D. M. Young, F. Hostettler et al., “Polyesters from Lactone”, Union Carbide F-40, p. 147. Particular examples of polyester polyols derived from caprolactone include polyesterdiols available as CAPA® 2047 and CAPA® 2077 from Ingevity. When more than one polyester polyol derived from caprolactone is used, often at least one of the polyols has a number average molecular weight greater than 500 g / mol, as determined by gel permeation chromatography using polystyrene as a standard.

[0026] The polyol component (ii) used to prepare the prepolymer (a) may comprise an additional polyol different from the polyester polyol(s). Such additionalpolyols may include one or more of any of those listed above; in particular, trimethylolpropane.

[0027] The equivalent ratio of isocyanate functional groups in the polyisocyanate component (i) to hydroxyl functional groups in the polyol component (ii) may range from 3.5:1 to 2:1 , such as from 3.2:1 to 2:1 ; or from 2.8:1 to 2:1. Typically, the isocyanate equivalent weight of the resultant isocyanate-functional prepolymer (a) ranges from 300 to 700 g / equivalent, such as from 300 to 500 g / equivalent.

[0028] The organic polymerizable composition further comprises (b) an aromatic diamine having at least one primary amino group. Non-limiting examples of suitable aromatic diamines include phenylene diamines and toluene diamines, for example o-phenylene diamine and p-tolylene diamine. Polynuclear aromatic diamines such as 4,4’-biphenyl diamine, 4,4’-methylene dianiline and monochloro- and dichloroderivatives of 4,4’-methylene dianiline are also suitable.

[0029] Suitable diamines can include but are not limited to materials having the following chemical formula:wherein Ri and R2 can each be independently chosen from methyl, ethyl, propyl, and isopropyl groups, and R3 can be chosen from hydrogen and chlorine. Non-limiting examples of such diamines include the following compounds, manufactured by Lonza Ltd. (Basel, Switzerland):LONZACURE® M-DIPA: RI=C3H7; R2=C3H7; R3=HLONZACURE® M-DMA: RI=CH3; R2=CH3; R3=HLONZACURE® M-MEA: RI=CH3; R2=C2H5; R3=HLONZACURE® M-DEA: Ri=C2H5; R2=C2H5; R3=HLONZACURE® M-MIPA: RI=CH3; R2=C3H7; R3=HLONZACURE® M-CDEA: RI=C2H5; R2=C2H5; R3=CIwherein Ri, R2 and R3 correspond to the aforementioned chemical formula.

[0030] The diamine can include a compound such as 4,4'-methylenebis(3- chloro-2,6-diethylaniline), (Lonzacure® M-CDEA), which is available in the United States from Air Products and Chemical, Inc. (Allentown, Pa.); 2,4-diamino-3,5-diethyl- toluene, 2,6-diamino-3,5-diethyl-toluene and mixtures thereof (collectively "diethyltoluenediamine" or "DETDA"), which is commercially available from Ketjen Corporation under the trade name Ethacure® 100; dimethylthiotoluenediamine (DMTDA), which is commercially available from Albemarle Corporation under the trade name Ethacure® 300; 4,4’-methylene-bis-(2-chloroaniline) which is commercially available from Kingyorker Chemicals as MOCA. The color stabilized version of Ethacure® 100 (i.e., formulation which contains an additive to reduce yellow color), which is available under the name Ethacure® 100S may be used in the organic polymerizable composition.

[0031] Other examples of the aromatic diamine can include one or more isomers of C1-C3 dialkyl toluenediamine, such as but not limited to 3,5-dimethyl-2,4- toluenediamine, 3,5-dimethyl-2,6-toluenediamine, 3,5-diethyl-2,4-toluenediamine,3.5-diethyl-2,6-toluenediamine, 3,5-diisopropyl-2,4-toluenediamine, 3,5-diisopropyl-2.6-toluenediamine, and mixtures thereof. Methylene dianiline and trimethyleneglycol di(para-aminobenzoate) are also suitable.

[0032] The equivalent ratio of isocyanate functional groups in the prepolymer to primary amino groups in the aromatic diamine may range from 0.75:1 to 1 :0.75.

[0033] The organic polymerizable compositions disclosed herein may further comprise a urethanation catalyst and / or other additional components. Non-limiting examples of suitable catalysts can be chosen from the group of Lewis bases, Lewis acids, and insertion catalysts as described in Ullmann’s Encyclopedia of Industrial Chemistry, 5th Edition, 1992, Volume A21 , pp. 673 to 674. The catalyst can be a stannous salt of an organic acid, such as but not limited to stannous octoate, dibutyl tin dilaurate, dibutyl tin diacetate, dibutyl tin mercaptide, dibutyl tin dimaleate, dimethyl tin diacetate, dibutyltin dichloride, and mixtures thereof. The catalyst can alternately be zinc octoate, bismuth, or ferric acetylacetonate.

[0034] Further non-limiting examples of suitable catalysts can include tin compounds such as dibutyl tin oxide, phosphines such as trioctyl phosphine, ammonium salts, and tertiary amines, such as but not limited to triethylamine,triisopropylamine, dimethyl cyclohexylamine, 1 ,4-diazabicyclo[2.2.2]octane, N,N- dimethylbenzylamine, and mixtures thereof.

[0035] When employed, the catalyst level can vary and can be dependent upon a variety of factors, such as the type and amounts of the reactive compounds used, as well as reaction conditions, speed of reaction, and degree of reaction desired. Typically, an organotin catalyst is present in an amount less than 300 ppm, often less than 250 ppm, and a tertiary amine catalyst is present in an amount less than 1000 ppm, usually less than 800 ppm, often about 720 ppm, each based on the total weight of the prepolymer (a) and the component (b).

[0036] Other commonly used solvents and / or additives can be included in the compositions, if desired. Suitable solvents may include any organic solvents known to those skilled in the art, provided they are not reactive with isocyanate functional groups. Examples of solvents are ketones, furans, ethers, aromatic solvents, and chlorinated solvents. Suitable solvents can include but are not limited to acetone, amyl propionate, anisole, benzene, butyl acetate, cyclohexane, dialkyl ethers of ethylene glycol, e.g., diethylene glycol dimethyl ether and their derivatives (sold as CELLOSOLVE® industrial solvents), diethylene glycol dibenzoate, dimethyl sulfoxide, dimethyl formamide, dimethoxybenzene, ethyl acetate, methyl cyclohexanone, cyclopentanone, methyl ethyl ketone, methyl isobutyl ketone, methyl propionate, propylene carbonate, tetrahydrofuran, toluene, xylene, 2-methoxyethyl ether, 3- propylene glycol methyl ether, methylene chloride, and mixtures thereof. Suitable additives can include but are not limited to light stabilizers, heat stabilizers, mold release agents, antioxidants, ultraviolet light absorbers, colorants, and flexibilizing additives.

[0037] The organic polymerizable composition includes a photochromic compound. As used herein, the term “photochromic” and similar terms, such as “photochromic compound” means having an absorption spectrum for at least visible radiation that varies in response to absorption of at least actinic radiation.

[0038] As used herein, the term “actinic radiation” means electromagnetic radiation that is capable of causing a response in a material, such as, but not limited to, transforming a photochromic compound from one form or state to another as discussed in further detail herein.

[0039] As used herein, the term “photochromic compound” includes thermally reversible photochromic materials and compounds. The term “thermally reversible photochromic compounds / materials” as used herein means compounds / materials capable of converting from a first state (such as a “clear state”) to a second state (such as a “colored state”) in response to actinic radiation, and reverting back to the first state in response to thermal energy.

[0040] As used herein, to modify the term “state”, the terms “first” and “second” are not intended to refer to any particular order or chronology, but instead refer to two different conditions or properties. For purposes of non-limiting illustration, the first state and the second state of a photochromic compound can differ with respect to at least one optical property, such as but not limited to the absorption of visible and / or UV radiation. Thus, according to the disclosure herein, the photochromic compounds used in conjunction with the present disclosure can have a different absorption spectrum in each of the first and second state. For example, while not limiting herein, a photochromic compound used in conjunction with the present disclosure can be clear in the first state and colored in the second state. Alternatively, a photochromic compound used in conjunction with the present disclosure can have a first color in the first state and a second color in the second state.

[0041] Suitable photochromic compounds may include any of those known in the art, including chromenes, such as naphthopyrans, benzopyrans, indeno-fused naphthopyrans, phenanthropyrans or mixtures thereof; spiropyrans, such as spiro(benzindoline)naphthopyrans, spiro(indoline)benzopyrans, spiro(indoline)naphthopyrans, spiro(indoline)quinopyrans and spiro(indoline)pyrans; oxazines, such as spiro(indoline)naphthoxazines, spiro(indoline)pyridobenzoxazines, spiro(benzindoline)pyridobenzoxazines, spiro(benzindoline)naphthoxazines and spiro(indoline)benzoxazines; metal dithizonates; fulgides; fulgimides; and mixtures thereof. The photochromic compound may contain a functional group that is reactive with the polyol component or the polyisocyanate component. In this scenario, the functional group may chemically bond the compound to the prepolymer and / or the final polymerizate, inhibiting migration of the compound. Functional groups reactive with the polyisocyanate component include, for example, active hydrogen groups such as hydroxyl, primary or secondary amino, thio, carboxyl (-C(O)OH), and the like. In a circumstance when the photochromic compound contains a functional group that isreactive with the polyol component or the polyisocyanate component, the photochromic compound may be included as a third component (iii) in the reaction mixture used to prepare the prepolymer. Such a photochromic compound, comprising a functional group that is reactive with the isocyanate-functional prepolymer (a), may additionally or alternatively be present as a separate, third component (c) in the organic polymerizable composition. Combinations of two or more photochromic compounds may be used to produce a desired color. There may be two or more different photochromic compounds in the reaction mixture used to prepare the prepolymer, and there may be two or more different photochromic compounds in the organic polymerizable composition. When a photochromic compound is present in both the reaction mixture and the bulk organic polymerizable composition, they may be the same or different from each other. The photochromic compound is typically present in the organic polymerizable composition in an amount of 0.10 to 10.0 percent, such as 0.2 to 7.0 percent, or 0.2 to 5.0 percent, based on the total weight of solids in the organic polymerizable composition. Solids (i. e., non-volatile) content may be determined using ASTM D1353-13 (2021 ). When used in the reaction mixture to prepare the prepolymer, the photochromic compound is typically present in the reaction mixture to prepare the prepolymer in an amount of 0.12 to 12.0 percent, such as 0.24 to 8.5 percent, or 0.24 to 6.0 percent, based on the total weight of reactants in the reaction mixture.

[0042] In certain examples, the organic polymerizable composition may further comprise a monomeric polyisocyanate, for example, isophorone diisocyanate, in addition to the prepolymer (a), the component (b), and any additional components mentioned above. When used, the monomeric polyisocyanate is typically present in the organic polymerizable composition in an amount of 0.05 to 20 percent, based on the total weight of solids in the organic polymerizable composition.

[0043] In certain examples of the organic polymerizable composition, at least one component (such as, but not limited to, any of the polyisocyanates, polyols, or solvents) may be prepared from a biobased carbon source. For example, the aliphatic polyisocyanate (1 ), in particular, isophorone diisocyanate, may be prepared from a biobased carbon source (“biomass”). In a particular example, the isophorone diisocyanate may be prepared from acetone that is a by-product of fermentation of hemicellulose. Hemicellulose is a matrix polysaccharide that is present alongwith cellulose in terrestrial plant cell walls. The organic polymerizable composition may comprise at least 20 percent, or at least 30 percent, or at least 40 percent, or at least 50 percent biobased carbon, based on the total carbon content of the organic polymerizable composition. The use of components derived from biobased carbon sources improves the sustainability of the final product.

[0044] The reactive components of the organic polymerizable composition as described above may be reacted together to yield a polymerizate as further demonstrated in the Examples below.

[0045] Any of the above-described organic polymerizable compositions are particularly useful in the production of molded optical articles formed from the polymerizate, for example, transparencies, glazings, tinted or untinted lenses, windshields, sunglasses, fashion lenses, piano and prescription lenses, sport masks, face shields, and goggles. The above-described organic polymerizable compositions are also useful in the production of components for augmented reality, virtual reality, mixed reality, or smart eyewear.

[0046] The aforementioned organic polymerizable composition may be introduced into a mold of any desired shape at a temperature and for a time to form a polymerizate, such as a thermoset polymerizate. The reaction mixture can undergo an exothermic reaction and, after mixing, it is introduced, usually by injection, into a mold and, in the case of lenses, usually a glass mold. The temperature of the reaction mixture as it is introduced into the mold can be up to 130°C, often up to 120°C. The reaction mixture is held in the mold at a temperature and for a time sufficient to essentially cure the reaction mixture and form a molded optical article. The mold may have any shape desired for the final product. It is typically a lens mold; often a mold for an ophthalmic lens. The molded article may then be released from the mold. Alternatively, the reaction mixture, which can be optionally degassed, can be introduced, usually by injection, into a mold and the mold can be heated (i.e. , using a thermal cure cycle) using a variety of conventional techniques known in the art. The thermal cure cycle can vary depending on the reactivity and molar ratio of the reactants, and the presence of catalyst(s). The thermal cure cycle can include heating the mixture from room temperature to a temperature of 200°C over a period of from 0.5 hours to 120 hours; or from 80 to 150°C for a period of from 5 hours to 72 hours.

[0047] An 8 mm thick optical article of the present disclosure typically demonstrates an opacity value of less than 28%, or less than 27%, measured using a HunterLab Ultra Scan PRO Spectrophotometer according to manufacturer instructions. An 12 mm thick optical article of the present disclosure typically demonstrates an opacity value of less than 51%, or less than 50%, measured using a HunterLab Ultra Scan VIS Spectrophotometer according to manufacturer instructions. Thus, the present disclosure also provides a method of reducing opacity in an optical article, comprising:(a) preparing an isocyanate-functional prepolymer by reacting together:(i) a polyisocyanate component comprising (1 ) an aliphatic polyisocyanate having at least one primary and at least one secondary isocyanate functional group; and (2) 4,4'-methylenebis(cyclohexyl isocyanate), wherein the equivalent ratio of isocyanate-functional groups in the aliphatic polyisocyanate (1 ) to isocyanate- functional groups in the 4,4'-methylenebis(cyclohexyl isocyanate) (2) is from 1 :8 to 5:1 , or from 1 :7.5 to 4.75:1 ; and(ii) a polyol component comprising a di- and / or tri-functional polyol having a calculated hydroxyl equivalent weight of 150 to 2500 grams / equivalent, or 200 to 2500 grams / equivalent, or 150 to 2000 grams / equivalent, or 200 to 2000 grams / equivalent;(b) reacting the prepolymer formed in (a) with an aromatic diamine having at least one primary amino group, in the presence of a photochromic compound to form a polymerizate; and(c) forming an optical article from the polymerizate.

[0048] Additionally or alternatively, a photochromic compound may be included as a third component in the reaction mixture used to prepare the prepolymer, particularly when the photochromic compound contains a functional group that is reactive with the polyol component or the polyisocyanate component. The prepolymer may be prepared using polymerization techniques known in the art, and as shown in the following Examples.

[0049] Each component used in the method may be any of those disclosed above, and the optical article may be formed as disclosed above.

[0050] The present disclosure is also directed to the following aspects:1 . An organic polymerizable composition comprising:(a) An isocyanate-functional prepolymer prepared from a reaction mixture comprising:(i) a polyisocyanate component comprising (1 ) an aliphatic polyisocyanate having at least one primary and at least one secondary isocyanate functional group; and (2) 4,4'-methylenebis(cyclohexyl isocyanate), wherein the equivalent ratio of isocyanate-functional groups in the aliphatic polyisocyanate (1 ) to isocyanate-functional groups in the 4,4'-methylenebis(cyclohexyl isocyanate) (2) is from 1 :8 to 5:1 ; and(ii) a polyol component comprising a di- and / or tri-functional polyol having a calculated hydroxyl equivalent weight of 150 to 2500 grams / equivalent;(b) an aromatic diamine having at least one primary amino group; and(c) a photochromic compound.2. The organic polymerizable composition of aspect 1 , wherein the equivalent ratio of isocyanate-functional groups in the aliphatic polyisocyanate (1 ) to isocyanate-functional groups in the 4,4'- methylenebis(cyclohexyl isocyanate) (2) is from 1 :7.5 to 4.75:1 .3. The organic polymerizable composition of any preceding aspect, wherein the di- and / or tri-functional polyol has a calculated hydroxyl equivalent weight of 200 to 2500 grams / equivalent.4. The organic polymerizable composition of any preceding aspect, wherein the di- and / or tri-functional polyol has a calculated hydroxyl equivalent weight of 150 to 2000 grams / equivalent.5. The organic polymerizable composition of any preceding aspect, wherein the di- and / or tri-functional polyol has a calculated hydroxyl equivalent weight of 200 to 2000 grams / equivalent.6. The organic polymerizable composition of any preceding aspect wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at least 10 percent by weight, and at most 80 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the 4,4'-methylenebis(cyclohexyl isocyanate) (2).7. The organic polymerizable composition of any preceding aspect wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at least 20 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the 4,4'- methylenebis(cyclohexyl isocyanate) (2).8. The organic polymerizable composition of any preceding aspect wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at least 30 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the 4,4'- methylenebis(cyclohexyl isocyanate) (2).9. The organic polymerizable composition of any preceding aspect wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at least 40 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the 4,4'- methylenebis(cyclohexyl isocyanate) (2).10. The organic polymerizable composition of any preceding aspect wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at most 70 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the 4,4'- methylenebis(cyclohexyl isocyanate) (2).1 1 . The organic polymerizable composition of any preceding aspect wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at most 60 percent by weight, based onthe total weight of the aliphatic polyisocyanate (1 ) and the 4,4'- methylenebis(cyclohexyl isocyanate) (2).12. The organic polymerizable composition of any preceding aspect, wherein the aliphatic polyisocyanate (1 ) comprises isophorone diisocyanate.13. The organic polymerizable composition of aspect 12, wherein at least one component is prepared from a biobased carbon source.14. The organic polymerizable composition of aspect 13 or 14, wherein the isophorone diisocyanate is prepared from acetone that is a by-product of fermentation of hemicellulose.15. The organic polymerizable composition of any preceding aspect, wherein the polyol component (ii) comprises at least one polyester polyol.16. The organic polymerizable composition of aspect 15, wherein the polyester polyol is derived from caprolactone or comprises a mixture of up to four different polyester polyols derived from caprolactone.17. The organic polymerizable composition of any preceding aspect, wherein the polyol component (ii) further comprises trimethylol propane.18. The organic polymerizable composition of any preceding aspect, wherein the aromatic diamine (b) comprises diethyltoluene diamine.19. The organic polymerizable composition of any preceding aspect, wherein the reaction mixture further comprises (iii) a photochromic compound containing a functional group that is reactive with the polyisocyanate component (i).20. The organic polymerizable composition of any preceding aspect, wherein the photochromic compound (c) comprises a functional group that is reactive with the isocyanate-functional prepolymer (a).21. The organic polymerizable composition of aspect 19 or 20, wherein the functional group comprises a hydroxy group, a primary amino group, a secondary amino group, a carboxylic acid group, and / or a thio group.22. The organic polymerizable composition of any of aspects 19 to 21 , wherein the photochromic compound (iii) is the same as or different from the photochromic compound (c).23. The organic polymerizable composition of any preceding aspect, further comprising (d) isophorone diisocyanate.24. The organic polymerizable composition of any of aspects preceding aspect, wherein the photochromic compound (c) comprises two or more different photochromic compounds.25. A polymerizate formed from the organic polymerizable composition of any preceding aspect.26. An optical article formed from the polymerizate of aspect 25.27. The optical article of aspect 26, wherein said optical article comprises a transparency; a glazing; a tinted or untinted lens; a piano or prescription lens; a sport mask; a face shield; a component for augmented reality, virtual reality, mixed reality, or smart eyewear; or goggles.28. An organic polymerizable composition comprising:(a) an isocyanate-functional prepolymer prepared from a reaction mixture comprising:(i) a polyisocyanate component comprising (1 ) an aliphatic polyisocyanate having at least one primary and at least one secondary isocyanate functional group; and (2) 4,4'-methylenebis(cyclohexyl isocyanate), wherein the equivalent ratio of isocyanate-functional groups in the aliphatic polyisocyanate (1 ) to isocyanate-functional groups in the 4,4'-methylenebis(cyclohexyl isocyanate) (2) is from 1 :8 to 5:1 ;(ii) a polyol component comprising a di- and / or tri-functional polyol having a calculated hydroxyl equivalent weight of 150 to 2500 grams / equivalent; and(iii) a photochromic compound containing a functional group that is reactive with the polyisocyanate component (i); and(b) an aromatic diamine having at least one primary amino group.29. The organic polymerizable composition of aspect 28, wherein the di- and / or tri-functional polyol has a calculated hydroxyl equivalent weight of 200 to 2500 grams / equivalent.30. The organic polymerizable composition of aspect 28 or 29, wherein the di- and / or tri-functional polyol has a calculated hydroxyl equivalent weight of 150 to 2000 grams / equivalent.31 . The organic polymerizable composition of any of aspects 28 to30, wherein the di- and / or tri-functional polyol has a calculated hydroxyl equivalent weight of 200 to 2000 grams / equivalent.32. The organic polymerizable composition of any of aspects 28 to31 , wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at least 10 percent by weight, and at most 80 percent by weight, based on the total weight of the aliphatic polyisocyanate (1) and the 4,4'-methylenebis(cyclohexyl isocyanate) (2).33. The organic polymerizable composition of any of aspects 28 to32, wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at least 20 percent by weight, based on the total weight of the aliphatic polyisocyanate (1) and the 4,4'-methylenebis(cyclohexyl isocyanate) (2).34. The organic polymerizable composition of any of aspects 28 to33, wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at least 30 percent by weight, based on the total weight of the aliphatic polyisocyanate (1) and the 4,4'-methylenebis(cyclohexyl isocyanate) (2).35. The organic polymerizable composition of any of aspects 28 to34, wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at least 40 percent by weight, based on the total weight of the aliphatic polyisocyanate (1) and the 4,4'-methylenebis(cyclohexyl isocyanate) (2).36. The organic polymerizable composition of any of aspects 28 to35, wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at most 70 percent by weight, based on the total weight of the aliphatic polyisocyanate (1) and the 4,4'-methylenebis(cyclohexyl isocyanate) (2).37. The organic polymerizable composition of any of aspects 28 to36, wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at most 60 percent by weight, based on the total weight of the aliphatic polyisocyanate (1) and the 4,4'-methylenebis(cyclohexyl isocyanate) (2).38. The organic polymerizable composition of any of aspects 28 to37, wherein the equivalent ratio of isocyanate-functional groups in thealiphatic polyisocyanate (1) to isocyanate-functional groups in the 4,4'- methylenebis(cyclohexyl isocyanate) (2) is from 1 :7.5 to 4.75:1 .39. The organic polymerizable composition of any of aspects 28 to 38, wherein the aliphatic polyisocyanate (1 ) comprises isophorone diisocyanate.40. The organic polymerizable composition of aspect 39, wherein at least one component is prepared from a biobased carbon source.41 . The organic polymerizable composition of aspect 40, wherein the isophorone diisocyanate is prepared from acetone that is a by-product of fermentation of hemicellulose.42. The organic polymerizable composition of any of aspects 28 to 41 , wherein the wherein the polyol component (ii) comprises at least one polyester polyol.43. The organic polymerizable composition aspect 42, wherein the polyester polyol is derived from caprolactone or comprises a mixture of up to four different polyester polyols derived from caprolactone.44. The organic polymerizable composition of any of aspects 28 to43, wherein the polyol component (ii) further comprises trimethylol propane.45. The organic polymerizable composition of any of aspects 28 to44, wherein the aromatic diamine comprises diethyltoluene diamine.46. The organic polymerizable composition of any of aspects 28 to45, wherein the photochromic compound (iii) comprises two or more different photochromic compounds.47. The organic polymerizable composition of any of aspects 28 to 46, further comprising (c) isophorone diisocyanate.48. A polymerizate formed from the organic polymerizable composition of any of aspects 28 to 47.49. An optical article formed from the polymerizate of aspect 48.50. The optical article of aspect 49, wherein said optical article comprises a transparency; a glazing; a tinted or untinted lens; a piano or prescription lens; a sport mask; a face shield; a component for augmented reality, virtual reality, mixed reality, or smart eyewear; or goggles.51 . A method of reducing opacity in an optical article, comprising:(a) preparing an isocyanate-functional prepolymer by reacting together:(i) a polyisocyanate component comprising (1 ) an aliphatic polyisocyanate having at least one primary and at least one secondary isocyanate functional group; and (2) 4,4'-methylenebis(cyclohexyl isocyanate), wherein the equivalent ratio of isocyanate-functional groups in the aliphatic polyisocyanate (1 ) to isocyanate-functional groups in the 4,4'-methylenebis(cyclohexyl isocyanate) (2) is from 1 :8 to 5:1 ; and(ii) a polyol component comprising a di- and / or tri-functional polyol having a calculated hydroxyl equivalent weight of 150 to 2500 grams / equivalent;(b) reacting the prepolymer formed in (a) with an aromatic diamine having at least one primary amino group, in the presence of a photochromic compound to form a polymerizate; and(c) forming an optical article from the polymerizate.52. The method of aspect 51 , wherein the equivalent ratio of isocyanate-functional groups in the aliphatic polyisocyanate (1 ) toisocyanate-functional groups in the 4,4'-methylenebis(cyclohexyl isocyanate) (2) is from 1 :7.5 to 4.75:1 .53. The method of aspect 51 or 52, wherein the di- and / or trifunctional polyol has a calculated hydroxyl equivalent weight of 200 to 2500 grams / equivalent.54. The method of any of aspects 51 to 53, wherein the di- and / or trifunctional polyol has a calculated hydroxyl equivalent weight of 150 to 2000 grams / equivalent.55. The method of any of aspects 51 to 54, wherein the di- and / or trifunctional polyol has a calculated hydroxyl equivalent weight of 200 to 2000 grams / equivalent.56. The method of any of aspects 51 to 55, wherein the photochromic compound comprises a functional group that is reactive with the isocyanate-functional prepolymer.57. The method of any of aspects 51 to 56, wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at least 10 percent by weight, and at most 80 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the 4,4'-methylenebis(cyclohexyl isocyanate) (2).58. The method of any of aspects 51 to 57, wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at least 20 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the 4,4'-methylenebis(cyclohexyl isocyanate) (2).59. The method of any of aspects 51 to 58, wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in anamount of at least 30 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the 4,4'-methylenebis(cyclohexyl isocyanate) (2).60. The method of any of aspects 51 to 59, wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at least 40 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the 4,4'-methylenebis(cyclohexyl isocyanate) (2).61 . The method of any of aspects 51 to 60, wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at most 70 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the 4,4'-methylenebis(cyclohexyl isocyanate) (2).62. The method of any of aspects 51 to 61 , wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at most 60 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the 4,4'-methylenebis(cyclohexyl isocyanate) (2).63. The method of any of aspects 51 to 62, wherein the aliphatic polyisocyanate (1 ) comprises isophorone diisocyanate.64. The method of any of aspects 51 to 63, wherein the polyol component (ii) comprises at least one polyester polyol.65. The method of aspect 64, wherein the polyester polyol is derived from caprolactone or comprises a mixture of up to four different polyester polyols derived from caprolactone.66. The method of any of aspects 51 to 65, wherein the polyol component (ii) further comprises trimethylol propane.67. The method of any of aspects 51 to 66, wherein the aromatic diamine comprises diethyltoluene diamine.68. A method of reducing opacity in an optical article, comprising:(a) preparing an isocyanate-functional prepolymer by reacting together:(i) a polyisocyanate component comprising (1 ) an aliphatic polyisocyanate having at least one primary and at least one secondary isocyanate functional group; and (2) 4,4'-methylenebis(cyclohexyl isocyanate), wherein the equivalent ratio of isocyanate-functional groups in the aliphatic polyisocyanate (1 ) to isocyanate-functional groups in the 4,4'-methylenebis(cyclohexyl isocyanate) (2) is from 1 :8 to 5:1 ;(ii) a polyol component comprising a di- and / or tri-functional polyol having a calculated hydroxyl equivalent weight of 150 to 2500 grams / equivalent; and(iii) a photochromic compound containing a functional group that is reactive with the polyisocyanate component (i);(b) reacting the prepolymer formed in (a) with an aromatic diamine having at least one primary amino group; and(c) forming an optical article from the polymerizate.69. The method of aspect 68, wherein the equivalent ratio of isocyanate-functional groups in the aliphatic polyisocyanate (1 ) to isocyanate-functional groups in the 4,4'-methylenebis(cyclohexyl isocyanate) (2) is from 1 :7.5 to 4.75:1 .70. The method of aspect 68 or 69, wherein the di- and / or tri- functional polyol has a calculated hydroxyl equivalent weight of 200 to 2500 grams / equivalent.71 . The method of any of aspects 68 to 70, wherein the di- and / or trifunctional polyol has a calculated hydroxyl equivalent weight of 150 to 2000 grams / equivalent.72. The method of any of aspects 68 to 70, wherein the di- and / or trifunctional polyol has a calculated hydroxyl equivalent weight of 200 to 2000 grams / equivalent.

[0051] The following working Examples are intended to further describe and demonstrate the compositions, polymerizates, optical articles, and methods described herein. It is understood that the disclosure of this specification is not necessarily limited to the examples described in this section. Components that are mentioned elsewhere in the specification as suitable alternative materials for use, but which are not demonstrated in the working Examples below, are expected to provide results comparable to their demonstrated counterparts. Unless otherwise indicated, all parts are by weight.EXAMPLES

[0052] The reactants used in the examples are as follows:Example 1

[0053] An isocyanate-functional prepolymer was prepared wherein the weight ratio of the polyisocyanate (1 ) to the 4,4'-methylenebis(cyclohexyl isocyanate) (2) was 10:90 and the equivalent ratio was 1 :7.59. To a reactor was charged 4,4- dicyclohexylmethane diisocyanate (507 grams, 3.87 equivalents), isophorone diisocyanate (56.3 grams, 0.51 equivalents), CAPA 2047A (260.1 grams, 1 .3 equivalents), CAPA 2077A (70.1 grams, 0.19 equivalents), CAPA 2403D (81 .3 grams, 0.04 equivalents), and trimethylolpropane (TMP) (4.3 grams, 0.1 equivalents). The contents were stirred circa 600 rpm under a continuous nitrogen blanket. The reactor was subjected to heating to maintain an internal temperature of 80°C. The reaction was carried out until reaching an isocyanate content of 12% (isocyanate equivalent weight ~ 350 g / eq) as indicated by titration. The isocyanate content of the prepared isocyanate-functional prepolymer in each Example was determined by reaction with an excess of n-dibutylamine (DBA) to form the corresponding urea followed by titration of the unreacted DBA with HCI in accordance with ASTM-2572-97. A Metrohm 809 Titrando autotitrator unit equipped with 800 Dosino dosing units was utilized for the titration process.Example 2

[0054] An isocyanate-functional prepolymer was prepared wherein the weight ratio of the polyisocyanate (1 ) to the 4,4'-methylenebis(cyclohexyl isocyanate) (2) was 20:80 and the equivalent ratio was 1 :3.37. To a reactor was charged 4,4- dicyclohexylmethane diisocyanate (438.6 grams, 3.34 equivalents), isophorone diisocyanate (109.7 grams, 0.99 equivalents), CAPA 2047A (260.1 grams, 1 .3 equivalents), CAPA 2077A (70.1 grams, 0.19 equivalents), CAPA 2403D (81 .3 grams, 0.04 equivalents), and trimethylolpropane (TMP) (4.3 grams, 0.1 equivalents). The contents were stirred circa 600 rpm under a continuous nitrogen blanket. The reactor was subjected to heating to maintain an internal temperature of 80°C. The reaction was carried out until reaching an isocyanate content of 12% (isocyanate equivalent weight ~ 350 g / eq) as indicated by titration. The isocyanate content of the prepared isocyanate-functional prepolymer in each Example was determined by reaction with an excess of n-dibutylamine (DBA) to form the corresponding urea followed by titration of the unreacted DBA with HCI in accordance with ASTM-2572-97. A Metrohm 809 Titrando autotitrator unit equipped with 800 Dosino dosing units was utilized for the titration process.Example 3

[0055] An isocyanate-functional prepolymer was prepared wherein the weight ratio of the polyisocyanate (1 ) to the 4,4'-methylenebis(cyclohexyl isocyanate) (2) was 30:70 and the equivalent ratio was 1 :1.98. To a reactor was charged 4,4- dicyclohexylmethane diisocyanate (373.8 grams, 2.85 equivalents), isophorone diisocyanate (160.2 grams, 1.44 equivalents), CAPA 2047A (260.1 grams, 1 .3 equivalents), CAPA 2077A (70.1 grams, 0.19 equivalents), CAPA 2403D (81 .3 grams, 0.04 equivalents), and trimethylolpropane (TMP) (4.3 grams, 0.1 equivalents). The contents were stirred circa 600 rpm under a continuous nitrogen blanket. The reactor was subjected to heating to maintain an internal temperature of 80°C. The reaction was carried out until reaching an isocyanate content of 12% (isocyanate equivalent weight ~ 350 g / eq) as indicated by titration.Example 4

[0056] An isocyanate-functional prepolymer was prepared wherein the weight ratio of the polyisocyanate (1 ) to the 4,4'-methylenebis(cyclohexyl isocyanate) (2) was 40:60 and the equivalent ratio was 1 :1.27. To a reactor was charged 4,4- dicyclohexylmethane diisocyanate (312.3 grams, 2.38 equivalents), isophorone diisocyanate (208.2 grams, 1.87 equivalents), CAPA 2047A (260.1 grams, 1 .3 equivalents), CAPA 2077A (70.1 grams, 0.19 equivalents), CAPA 2403D (81 .3 grams, 0.04 equivalents), and trimethylolpropane (TMP) (4.3 grams, 0.1 equivalents). The contents were stirred circa 600 rpm under a continuous nitrogen blanket. The reactor was subjected to heating to maintain an internal temperature of 80°C. The reaction was carried out until reaching an isocyanate content of 12% (isocyanate equivalent weight ~ 350 g / eq) as indicated by titration.Example 5

[0057] An isocyanate-functional prepolymer was prepared wherein the weight ratio of the polyisocyanate (1 ) to the 4,4'-methylenebis(cyclohexyl isocyanate) (2) was 50:50 and the equivalent ratio was 1 .18:1. To a reactor was charged 4,4- dicyclohexylmethane diisocyanate (253.8 grams, 1 .93 equivalents), isophorone diisocyanate (253.8 grams, 2.28 equivalents), CAPA 2047A (260.1 grams, 1 .3 equivalents), CAPA 2077A (70.1 grams, 0.19 equivalents), CAPA 2403D (81 .3 grams, 0.04 equivalents), and TMP (4.3 grams, 0.1 equivalents). The contents were stirredcirca 600 rpm under a continuous nitrogen blanket. The reactor was subjected to heating to maintain an internal temperature of 80°C. The reaction was carried out until reaching an isocyanate content of 12% (isocyanate equivalent weight ~ 350 g / eq) as indicated by titration.Example 6

[0058] An isocyanate-functional prepolymer was prepared wherein the weight ratio of the polyisocyanate (1 ) to the 4,4'-methylenebis(cyclohexyl isocyanate) (2) was 60:40 and the equivalent ratio was 1 .77:1. To a reactor was charged 4,4- dicyclohexylmethane diisocyanate (198.1 grams, 1.51 equivalents), isophorone diisocyanate (297.2 grams, 2.67 equivalents), CAPA 2047A (260.1 grams, 1 .3 equivalents), CAPA 2077A (70.1 grams, 0.19 equivalents), CAPA 2403D (81 .3 grams, 0.04 equivalents), and trimethylolpropane (TMP) (4.3 grams, 0.1 equivalents). The contents were stirred circa 600 rpm under a continuous nitrogen blanket. The reactor was subjected to heating to maintain an internal temperature of 80°C. The reaction was carried out until reaching an isocyanate content of 12% (isocyanate equivalent weight ~ 350 g / eq) as indicated by titration.Example 7

[0059] An isocyanate-functional prepolymer was prepared wherein the weight ratio of the polyisocyanate (1 ) to the 4,4'-methylenebis(cyclohexyl isocyanate) (2) was 70:30 and the equivalent ratio was 2.75:1. To a reactor was charged 4,4- dicyclohexylmethane diisocyanate (145.1 grams, 1 .1 1 equivalents), isophorone diisocyanate (338.5 grams, 3.05 equivalents), CAPA 2047A (260.1 grams, 1 .3 equivalents), CAPA 2077A (70.1 grams, 0.19 equivalents), CAPA 2403D (81 .3 grams, 0.04 equivalents), and TMP (4.3 grams, 0.1 equivalents). The contents were stirred circa 600 rpm under a continuous nitrogen blanket. The reactor was subjected to heating to maintain an internal temperature of 80°C. The reaction was carried out until reaching an isocyanate content of 12% (isocyanate equivalent weight ~ 350 g / eq) as indicated by titration.Example 8 (Comparative)

[0060] An isocyanate-functional prepolymer was prepared with no polyisocyanate (1 ). To a reactor was charged 4,4-dicyclohexylmethane diisocyanate (579.3 grams, 4.42 equivalents), CAPA 2047A (260.1 grams, 1 .3 equivalents), CAPA2077 (70.1 grains, 0.19 equivalents), CAPA 2403D (81.3 grams, 0.04 equivalents), and TMP (4.3 grams, 0.1 equivalents). The contents were stirred circa 600 rpm under a continuous nitrogen blanket. The reactor was subjected to heating to maintain an internal temperature of 100°C. The reaction was carried out until reaching an isocyanate content of 12% (isocyanate equivalent weight ~ 350 g / eq) as indicated by titration.8 mm Prepolymer Casting

[0061] 37 grams (0.105 equivalents) of the prepolymer of Examples 2, 5, 7, andComparative Example 8 was warmed and mixed with 0.7 grams of a blend of hydroxyfunctional indeno-fusednaphthopyran photochromic compounds and 0.3 grams MoldWiz® INT 1681 (a mold release available from Axel Plastics Research Laboratories, Inc). The resulting mixture was degassed at 70-90°C for 4 hours. In a different vessel, 8.7 grams (0.098 equivalents) of PRIMACURE® DETDA 80 (DETDA) was kept under reduced pressure until degassed. Afterwards, each prepolymer mixture and DETDA were combined and subject to a 15-second mixing cycle using a Speedmixer DAC 400 high speed mixer, available from Hauschild Engineering. 35 grams of the resulting mixture was poured into a 75 mm diameter glass mold. The mold was subject to heating in an oven set to 125°C for 16 hours, then allowing to cool below 85°C and demolding to afford an 8 mm thick polymer disc.

[0062] A HunterLab Ultra Scan PRO Spectrophotometer was used according to the manufacturer’s instructions to collect opacity data on the resulting polymer discs. The opacity is influenced by, and proportional to, the thickness of the sample. The 8 mm thick discs exaggerate the effect to provide measurable differences in opacity among samples.12 mm Prepolymer Casting

[0063] 63 grams (0.18 equivalents) of the prepolymer of each Example was warmed and mixed with 1.2 grams of a blend of hydroxy-functional indeno- fusednaphthopyran photochromic compounds and 0.5 grams MoldWiz® INT 1681 (a mold release available from Axel Plastics Research Laboratories, Inc). The resulting mixture was degassed at 70-90°C for 4 hours. In a different vessel, 15 grams (0.17 equivalents) of PRIMACURE® DETDA 80 (DETDA) was kept under reduced pressure until degassed. Afterwards, each prepolymer mixture and DETDA were combined and subject to a 10-second mixing cycle using a Speedmixer DAC 400 high speed mixer,available from Hauschild Engineering. The resulting mixture was poured into a circular glass mold (82 mm diameter) with a 12 mm thick cavity. The mold was subject to heating in an oven set to 125°C for 16 hours, then allowing to cool below 85°C and demolding to afford a 12 mm thick polymer disc.

[0064] A HunterLab Ultra Scan VIS Spectrophotometer was used according to the manufacturer’s instructions to collect opacity data on the resulting polymer discs. The opacity is influenced by, and proportional to, the thickness of the sample. The 12 mm thick discs exaggerate the effect to provide measurable differences in opacity among samples.

[0065] TABLE 1 is a summary of the measured opacities of the 8 mm thick polymer discs:TABLE 1

[0066] Each of the 8 mm samples of Examples 2, 5 and 7 demonstrates an opacity value of less than 28 percent, as shown in TABLE 1 . It is believed that the 15- second mixing cycle of the prepolymer mixtures and DETDA (as opposed to the 10- second mixing cycle used for the 12 mm samples shown in TABLE 2 below) may have caused gelling that affected the opacity values, such that an expected downward trend of opacity values, proportional to the ratios of the polyisocyanate (1 ) to the 4,4'- methylenebis(cyclohexyl isocyanate) (2), was not observed.

[0067] TABLE 2 is a summary of the measured opacities of the 12 mm thick polymer discs:TABLE 2

[0068] Each of the discs darkened when exposed to ultraviolet (UV) radiation (corresponding to a “activated” state, demonstrating photochromic behavior). Upon removal of the UV radiation source, each disc returned to the “unactivated,” or undarkened, state.

[0069] Whereas particular examples of this disclosure have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present disclosure may be made without departing therefrom as defined in the appended claims. Although various examples of the disclosure have been described in terms of "comprising", embodiments consisting essentially of or consisting of are also within the scope of the present disclosure.

Claims

What is claimed is:1 . An organic polymerizable composition comprising:(a) An isocyanate-functional prepolymer prepared from a reaction mixture comprising:(i) a polyisocyanate component comprising (1 ) an aliphatic polyisocyanate having at least one primary and at least one secondary isocyanate functional group; and (2) 4,4'-methylenebis(cyclohexyl isocyanate), wherein the equivalent ratio of isocyanate-functional groups in the aliphatic polyisocyanate (1) to isocyanate-functional groups in the 4,4'-methylenebis(cyclohexyl isocyanate) (2) is from 1 :8 to 5:1 ; and(ii) a polyol component comprising a di- and / or tri-functional polyol having a calculated hydroxyl equivalent weight of 150 to 2500 grams / equivalent, or 200 to 2500 grams / equivalent, or 150 to 2000 grams / equivalent, or 200 to 2000 grams / equivalent ;(b) an aromatic diamine having at least one primary amino group; and(c) a photochromic compound.

2. The organic polymerizable composition of claim 1 , wherein the aliphatic polyisocyanate (1 ) is present in the polyisocyanate component (i) in an amount of at least 10 percent by weight, or at least 20 percent by weight, or at least 30 percent by weight, or at least 40 percent by weight, and at most 80 percent by weight, or at most 70 percent by weight, or at most 60 percent by weight, based on the total weight of the aliphatic polyisocyanate (1 ) and the ,4'-methylenebis(cyclohexyl isocyanate) (2).

3. The organic polymerizable composition of claim 1 or 2, wherein the equivalent ratio of isocyanate-functional groups in the aliphatic polyisocyanate (1 ) to isocyanate- functional groups in the 4,4'-methylenebis(cyclohexyl isocyanate) (2) is from 1 :7.5 to 4.75:1.

4. The organic polymerizable composition of any of claims 1 to 3, wherein the aliphatic polyisocyanate (1 ) comprises isophorone diisocyanate.

5. The organic polymerizable composition of claim 4, wherein at least one component is prepared from a biobased carbon source.

6. The organic polymerizable composition of claim 4 or 5, wherein the isophorone diisocyanate is prepared from acetone that is a by-product of fermentation of hemicellulose.

7. The organic polymerizable composition of any of claims 1 to 6, wherein the polyol component (ii) comprises at least one polyester polyol.

8. The organic polymerizable composition of claim 7, wherein the polyester polyol is derived from caprolactone or comprises a mixture of up to four different polyester polyols derived from caprolactone.

9. The organic polymerizable composition of any of claims 1 to 8, wherein the polyol component (ii) further comprises trimethylol propane.

10. The organic polymerizable composition of any of claims 1 to 9, wherein the aromatic diamine (b) comprises diethyltoluene diamine.

11. The organic polymerizable composition of any of claims 1 to 10, wherein the reaction mixture further comprises (iii) a photochromic compound containing a functional group that is reactive with the polyisocyanate component (i).

12. The organic polymerizable composition of any of claims 1 to 1 1 , wherein the photochromic compound (c) comprises a functional group that is reactive with the isocyanate-functional prepolymer (a).

13. The organic polymerizable composition of claim 11 or 12, wherein the functional group comprises a hydroxy group, a primary amino group, a secondary amino group, a carboxylic acid group, and / or a thio group.

14. The organic polymerizable composition of claim 1 1 , wherein the photochromic compound (iii) is the same as or different from the photochromic compound (c).

15. The organic polymerizable composition of any of claims 1 to 14, further comprising (d) isophorone diisocyanate.

16. The organic polymerizable composition of any of claims 1 to 15, wherein the photochromic compound (c) comprises two or more different photochromic compounds.

17. A polymerizate formed from the organic polymerizable composition of any of claims 1 to 16.

18. An optical article formed from the polymerizate of claim 17.

19. The optical article of claim 17 or claim 18, wherein said optical article comprises a transparency; a glazing; a tinted or untinted lens; a piano or prescription lens; a sport mask; a face shield; a component for augmented reality, virtual reality, mixed reality, or smart eyewear; or goggles.

20. An organic polymerizable composition comprising:(a) an isocyanate-functional prepolymer prepared from a reaction mixture comprising:(i) a polyisocyanate component comprising (1 ) an aliphatic polyisocyanate having at least one primary and at least one secondary isocyanate functional group; and (2) 4,4'- methylenebis(cyclohexyl isocyanate), wherein the equivalent ratio of isocyanate- functional groups in the aliphatic polyisocyanate (1 ) to isocyanate-functional groups in the 4,4'-methylenebis(cyclohexyl isocyanate) (2) is from 1 :8 to 5:1 , or from 1 :7.5 to 4.75:1 ;(ii) a polyol component comprising a di- and / or tri-functional polyol having a calculated hydroxyl equivalent weight of 150 to 2500 grams / equivalent, or 200 to 2500 grams / equivalent, or 150 to 2000 grams / equivalent, or 200 to 2000 grams / equivalent; and(iii) a photochromic compound containing a functional group that is reactive with the polyisocyanate component (i); and(b) an aromatic diamine having at least one primary amino group.

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