LAMINATING RESINS HAVING LOW ORGANIC EMISSIONS

Abstract: A laminating resin is made from (1) an unsaturated polyester resin, (2) a diacrylate or dimethacrylate of alkoxylated bisphenol-A, and (3) either (A) vinyl toluene, (B) ethylene glycol dimethacrylate, or (C) styrene, divinyl benzene or a combination thereof. The resin achieves excellent laminating resin properties, and is significantly inhibited from emitting volatiles during use. A method of laminating a solid formed body with the resin above is also described.

Description: LAMINATING RESINS HAVING LOW ORGANIC EMISSIONS Technical Field This invention relates to resin compositions which cure as they are shaped / laminated, brushed, sprayed or otherwise more or less incrementally placed into the space where they are to form a product; such resins are broadly known as laminating resins, commonly have an unsaturated polyester resin base, are mixed with glass fiber reinforcement, and nearly always are employed in a solution of an organic monomer such as styrene. The organic monomer is intended to copolymerize with the resin but typically and notoriously may also tend to volatilize in significant amounts into the workplace environment. The present invention is drawn to compositions and methods which can be used in existing equipment, procedures, and workplaces, but which will emit far less monomer than the typical laminating resins and methods heretofore. Background of the Invention Many attempts have been made to devise laminating resins having low volatile emissions and still meet the physical specifications and other desirable properties of the end products, while remaining relatively easy to use. In Lee U.S. Patent 4,465,806, for example, a more or less conventional unsaturated polyester resin is combined with, instead of the usual styrene, a reaction product of a polyepoxy compound and acrylic or methacrylic acid which may be the diacrylate of a polyglycidyl ether of bisphenol-A. These compounds are made from epoxy compounds, and the author of U.S. Patent 4,465,806 requires that a significant portion of the epoxy groups be unreacted for use in their resin. Moreover, unlike the present invention, they form pendant OH groups. Ethoxylated, difunctional, bisphenol-A has been used in the past as an ingredient in various types of resins, generally resins which include a significant diisocyanate component, as in Ford, Jr. et al U.S. Patent 3,876,726. European Patent Application 0 234 692 discloses a composition said to be useful as a molding resin, having the virtue of a low residual monomer concentration in the final product. The gist of the disclosure appears to be that dimethacrylates such as ethoxylated bisphenol-A dimethacrylate can be used as components of otherwise more or less conventional unsaturated polyester resins to reduce the amount of residual styrene monomer in contained molding processes such as cell molding, compression molding, and sheet molding. See also Reid and Rex U.S. Patent 5,202,366, which includes a low-profile additive in a similar composition. The daunting problem of volatile emissions during spray-up or other laminating procedures has until now been unsolved. Applicants' dramatic results detailed herein show that lamination can be used with significantly reduced emissions in the workplace. Summary of the Invention Our new laminating resins comprises three components. The first is a more or less conventional base resin comprising glycols and unsaturated dicarboxylic acids; optionally the base resin may also contain a saturated dicarboxylic acid. In polymeric form, they are typically maleic and phthalic acid residues, with optional isophthalic residues, interspersed with glycol residues. These glycols are commonly ethylene glycol, diethylene glycol, propylene glycol and dipropylene glycol, usually as mixtures, but many other glycols can be utilized; dicyclopentadiene may be included as well, as is known in the art. The second component is a diacrylate or dimethacrylate of alkoxylated bisphenol-A of the formula where m and n are independently numbers from 1 to about 10, and R 1 and R2 are independently, in each 3 alkoxy group, hydrogen or CH 3 , and each R is also independently hydrogen or CH 3 . Hydroxyethyl or hydroxypropyl groups can comprise about 19-71% of the weight of this ingredient. These two ingredients may be present in weight ratios of about 2.0:1 to about 0.5:1. The composition also includes a third ingredient which may be (1) about 20-60% based on the total of the two above ingredients of a compound of the formula where one H on the ring is substituted by CH 3 , or (2) about 20-60%, based on the total of the two above ingredients of ethylene glycol dimethacrylate, or (3) about 10-60% based on the total of the two above ingredients, of styrene, divinyl benzene or mixtures thereof. The above-described composition may also include from 1% to about 10% of N-vinyl pyrrolidone or 1% to about 20% cyclohexyl methacrylate or both, and/or 1% to about 30% of any combination of the following, provided the ingredient is not included above: ethylene glycol dimethacrylate, vinyl toluene, and divinyl benzene, all based on the overall composition. Since our objective is to design a composition which works very well as a laminating resin without significant emissions, the addition of styrene to the recipe is not required, but the composition will continue to be operable as an excellent laminating resin even though styrene is included either as the third ingredient, or as an additional component. The composition will also tolerate many other minor ingredients known to be useful in the unsaturated polyester and laminating art. Detailed Description of the Invention While the problem at hand is to create a formulation which drastically differs from commercial standard laminating resins in terms of volatile emissions during application, the market dictates that it must be accomplished without significantly altering the widely used equipment and techniques of application. Accordingly, the following criteria are to be kept in mind at all times: 1. Reduced emission of volatile organic compounds — regulations will become more stringent with time. 2. Less potential hazard to human health and the environment — regulations will also become more stringent with time. 3. Minimal increase in cost when commercialized, and reason to believe cost will be reduced in the long run. . Compatibility between components of the resin system. 5. Reactivity that is similar to that of styrenated polyester resins. 6. Viscosity that is similar to that of styrenated polyester resins - 100 to 400 cps. 7. Physical properties similar to or better than those of styrenated polyester resin. 8. Ability to wet glass and bond to other components of an assembly. Persons skilled in the art will realize that number 7, relating to physical properties of the final product, can by itself include several important specifications. Thus, the problem is not simply one of finding a monomer system which is not as volatile or objectionable as styrene alone. Rather, many criteria have to be balanced, and, with thousands of chemicals to consider, analysis of the combinations and their effects is extremely difficult. One must decide on the important functions and properties, settle on a systematic but simple screening process, and try to develop a short list of prospective formulations which have a good chance of meeting all the criteria within a practical time period. The proliferation of input variables to attain these objectives may be further appreciated by considering the more or less conventional unsaturated polyester compositions which may be used as a base. They are prepared by polycondensation of polycarboxylic acid derivatives, one of which must be an alpha, beta-ethylenically unsaturated polycarboxylic acid, and polyols. By polycarboxylic acid derivatives we mean to include polycarboxylic acids, their esters of lower alcohols, their acid chlorides and their anhydrides. The ratio of polycarboxylic acid to polyol is usually a 1:1 molar ratio. However, in most esterification processes, a slight excess of polyol is utilized to compensate for polyol losses during esterification. Also, although dicarboxylic acids and diols are most frequently utilized and the 1:1 molar ratio is prevalent, the utilization of triols and the like requires the ratio of acid to polyol to be stated more precisely as one equivalent of acid per equivalent of polyol. The unsaturated polyesters useful in this invention may be prepared from an acid mixture wherein the unsaturated polycarboxylic acid comprises as little as 20 mole percent of the total acids present, although it is generally preferred that the unsaturated polycarboxylic acid comprises about 30% or more of the total acid content. Some of the unsaturated polycarboxylic acids useful in preparing unsaturated polyesters used in this invention include: Maleic acid Citraconic acid Fumaric acid Glutaconic acid Itaconic acid Chloromaleic acid Mesaconic acid and the like, wherein the term "acid" is used to include the corresponding anhydrides where such anhydrides exist. Some of the saturated and aromatically unsaturated polycarboxylic acids optionally useful in preparing unsaturated polyesters used in this invention include: Phthalic acid Isophthalic acid Tetrahydrophthalic acid Hexahydrophthalic acid Endomethylene tetrahydrophthalic acid Tetrachlorophthalic acid Glutaric acid Hexachloroendomethylene tetrahydrophthalic acid Succinic acid Suberic acid Adipic acid Sebacic acid and the like, wherein the term "acid" includes the corresponding anhydrides where such anhydrides exist. Polyols useful in preparing polyesters for use in this invention are polyfunctional alcohols of the type conventionally utilized in polyester preparation. Such polyols include: Ethylene glycol 1,5 propanediol Propylene glycol Triethylene glycol Butylene glycol Glycerol Diethylene glycol 1,4,6-hexanetriol Trimethylolpropane Trimethylolethane Dipropylene glycol Pentaerythritol Neopentyl glycol Alkoxylated 2,2-bis(4-hydroxyphenyl) propane and the like. Although diols are generally preferred in the preparation of unsaturated polyesters, the more functional polyols, i.e. polyols having a functionality of three to five, are sometimes used. In addition, dicyclopentadiene may be included and may be considered a normal part of the "base resin" as used herein. During the development of the formulation, various monomers and monomer substitutes were screened, using two different "base" resins — one having dicyclopentadiene as a major ingredient and one without dicyclopentadiene. Following are results for the base resin without dicyclopentadiene: A base resin composition (hereafter designated "Resin A") was prepared having the following ingredients: Base Resin 60 parts by weight 12% Cobalt (Promoter) 00.30 Potassium (Co-promoter) 00.20 N,N-Dimethylacetoacetamide.... (Accelerator) 00.30 DDM-9 (Initiator) 01.50 Monomer (as indicated below)..40 k Parts by Base Resin (Polymer) weight lbs/100 lbs lbs/60 lbs Propylene Glycol - 22.788 31.97 19.18 Diethylene Glycol - 04.937 6.93 4.16 Phthalic Anhydride - 32.734 45.92 27.55 Maleic Anhydride - 10.820 15.18 9.11 71.279 100.00 60.00 The following "monomers" were utilized with Resin A: Monomer Mod I ' Viscosity Exotherm Gel Time Interval °F min:sec min:sec Styrene 0.120 low 335 4:30 4:39 Vinyl Toluene 0.120 low 317 4:50 5:04 Diallyl phthalate 0.000 high 119 19:27 27:43 Methacrylates n-butyl 0.001 low 186 40:58 5:28 n-hexyl 0.001 incompatible isodecyl 0.001 incompatible cyclohexyl 0.001 high* 287 16:50 3:50 2-phenoxyethyl 0.001 high 196 8:45 3:29 allyl 0.001 low 331 18:20 3:37 2-hydroxyethyl 0.001 low 247 4:48 3:35 2-hydroxyethyl 0.010 low 249 4:30 3:20 dicyclopentyl 0.001 very high 199 3:40 4:11 isobornyl 0.000 incompatible isophoronyl 0.010 incompatible o I Dimethacrylates 1,6-hexanediol 0.001 high 241 7:54 3:34 ethylene glycol (EG) 0.001 low 275 2:48 3:37 ethylene glycol 0.005 low 274 2:52 3:50 diethylene glycol 0.001 medium >210 4:03 2:12 diethylene glycol 0.010 medium 252 5:40 3:13 triethylene glycol 0.001 medium 241 3:18 3:17 tetraethylene glycol 0.001 medium 229 2:52 3:46 neopentyl glycol 0.001 high 235 4:20 4:09 ethoxylated BPA 0.001 very high 171 8:50 7:30 C14 diol 0.001 incompatible Trimethacrylate tri ethylol propane 0.001 high 228 2:28 4:25 Monomer Mod L1) Viscosity Exotherm Gel Time Interval op min:sec min:sec Mixtures 30 EG dimethacrylate/ 10 N-vinyl pyrrolidinone 0.010 medium 295 1:49 3:12 30 EG dimethacrylate/ 10 divinyl benzene 0.010 medium 286 3:11 3:29 30 vinyl toluene/ 10 N-vinyl pyrrolidinone 0.200 low 289 16:10 4:44 This was considered unsatisfactory, but when ethoxylated BPA dimethacrylate was included to make a 3-part mixture, viscosity was lowered. Of all the above monomers screened, only the N-vinyl pyrrolidinone, divinyl benzene, ethylene glycol dimethacrylate, styrene, cyclohexyl methacrylate, and vinyl toluene were not ruled out. The rest were eliminated from consideration because they were slow to react with polyester as shown by long gel time and/or low exotherm or they were not sufficiently compatible with polyester as shown by high viscosity or the outright failure to dissolve. 'Mod is 25% hydroquinone in propylene glycol. Liquid resin properties measured in the experiments reported below were gel time, (reported in the tables herein in minutes and seconds, as 13:17, for example), room temperature interval time, which is the time between gelation and the exothermic peak, room temperature exothermic peak which is the highest temperature reached in a 100 g mass of resin during the curing process, Brookfield viscosity, and Barcol hardness by ASTM D2583. For volatile emissions, we followed the Rule 1162 Standard Method for Static Volatile Emissions of the South Coast Air Quality Management District (California) which is incorporated herein by reference. This test is accepted as a predictor of volatile emissions in the workplace during spray-up lamination procedures. Its results are reported in two ways — grams per square meter of weight loss, and the time of emissions, in minutes and seconds. The latter measurement entails noting the point in time in which weight loss is no longer recorded, thus requiring that weight be monitored beyond the time noted. A brief outline of the test is as follows: An environment at 77°C and 50% relative humidity is maintained. If a controlled environment is not available, conditions should be reported for which measurements are made. A 200 gm pre-promoted resin is weighed out into a suitable dry and clean container. The container is covered and placed in a 25°C temperature bath. A balance is placed in a draft free enclosure. A gallon lid is cleaned with solvent and wiped dry. The diameter is measured to the nearest 0.1 cm. The gallon lid is placed on an inverted paper or plastic cup mounted on the balance pan. A bent paper clip is positioned in the center of the gallon lid. This weight (TARE WEIGHT) is recorded. The container is taken from the temperature bath and an appropriate volumetric or weight measure of catalyst is added. A timer is started at this point. The catalyst is mixed with the resin for one minute. The INITIAL WEIGHT is determined by pouring 100.0 + 0.5 gm of catalyzed resin into the can lid and recording the weight. Next, the paper clip is used to determine when the resin has hardened sufficiently to allow the resin or lid to be lifted. The time (gel time) is recorded at this point. The resin is then allowed to harden in the can lid and every 15 minutes it is reweighed until concurrent weights agree to within 0.05 gm. This is recorded as the FINAL WEIGHT. The entire procedure should be repeated until duplicate samples agree to the 2 nearest 5 gm/m . The volatile emissions per square meter are calculated as follows: Volatile Losses per _ INITIAL WEIGHT - FINAL WEIGHT Square Meter ~ Area of Sample in Square Meters The clear castings tests adopted were as follows: 1. Tensile strength - ASTM D638. 2. Tensile modulus - ASTM D638. 3. Elongation - ASTM D638. 4. Flexural strength - ASTM D790. 5. Flexural modulus - ASTM D790. 6. Heat deflection temperature - ASTM D648. 7. Water absorption at 150°F - ASTM D570 (modified). The water absorption test was modified as follows: the temperature was set at 150°F and long term immersion was set at one week. In the data reported in Tables I and IV, Resin A is as described above in terms of weight; it is, in molar equivalents, a polyester resin composed of 1.0 mole maleic anhydride, 2.0 moles phthalic anhydride, 0.42 mole diethylene glycol and 2.71 moles propylene glycol. Resin B is similar to Resin A with a lower viscosity by an adjustment of the cook, as is known in the art. Sartomer CD480 is ethoxylated bisphenol-A dimethacrylate where m and n in the above formula total 10. Sartomer 348 is ethoxylated bisphenol-A dimethacrylate where m and n in the above formula are both 1. Mod L is 25% hydroquinone and 75% propylene glycol. From the data in Table I, it can be seen that formulations Z, S, and 0 have better than acceptable resin properties and clear casting properties, and have volatile emissions far less than the rate of the more or less classical commercial resin A2. Formulation Z is about one-fifth the rate of A2. In Tables II and III, nine additional formulations are shown. From these it will be seen that cyclohexyl methacrylate causes undesirable properties when used as the only material in addition to the base resin and the ethoxylated BPA dimethacrylate. But there are extraordinarily low emissions from all nine of the formulations. The use of vinyl toluene to reduce the viscosity is certainly not detrimental to emissions results. In Tables IV and V, formulations containing both Sartomer and either styrene or divinyl benzene are seen to compare very well in terms of emissions with those not including styrene as a monomer. From these it will be seen that the use of alkoxylated BPA dimethacrylates have the effect of significantly reducing monomer emissions in styrene-containing laminating resins. TABLE I RESIN - A2 Q2 S Z hi Q Resin A - 60.00 60.00 40. 00 35.00 35.00 Resin B 45. 00 Sartomer CD480 15.00 15.00 15.00 10.00 Sartomer 348 20.00 20.00 20.00 15.00 EG Dimethacrylate 25.00 10.00 20.00 30.00 Vinyl Toluene 40.00 10.00 Cyclohexyl Methacrylate 10.00 Divinyl Benzene 10.00 Styrene - 40.00 ----- —— —-— — — Mod - 0.20 0.22 0.06 0.12 0.12 0.06 RESIN PROPERTIES Gel time, min:sec 12:59 13:17 21:18 18:29 11:30 5:20 Interval, min:sec 5:58 6:54 4:32 4:11 3:26 3:19 Exotherm peak, β F 345 324 249 276 294 245 Viscosity, cps, 75 β F 315 340 1,390 426 624 396 1162 Emissions, G/M2 31.5 20.6E 3.6 6.1 9.7 3.6 Barcol hardness 45 minutes 45 42 47 44 52 34 One hour 45 43 50 48 53 36 24 hours 49 49 52 51 54 36 CLEAR CASTING PROPERTIES Tensile strength, psi- 9,308 7,555 8,069 9,635 8,176 10,179 Ten. modulus, 10-5psi- 0.549 0.534 0.466 0.565 0.575 0.567 Elongation, % - 1.9 1.6 .3.2 2.7 1.9 2.3 Flexural strength,psi- 16,008 15,317 10,475 16,889 15,780 16,013 Flex modulus, 10-5psi- 0.586 0.573 0.322 0.444 0.482 0.498 Heat deflect. temp, β F- 144 138 169 142 147 141 Water absorption. % at 150"F One day - 0.89 0.91 1.01 1.19 1.26 1.43 7 days - 1.89 1.89 2.12 1.65 1.76 2.14A E - This value was estimated based on.the difference in results caused by using different end points for the 1162 test. A - The surfaces of the test specimens were alligatored. This indicates a more severe problem than the weight gain indicates. TABLE XI Low VOC Laminatinσ Resins Based on General Purpose Polvester Polvmer Resin E-3B F-3 Q-? H-3 1-3 Composition Resin A 35.00 35.00 35.00 35.00 35.00 Sartomer 480 15.00 15.00 15.00 15.00 15.00 Sartomer 348 20.00 20.00 20.00 20.00 20.00 EG Dimethacrylate 15.00 15.00 20.00 Cyclohexyl Methacrylate 30.00 15.00 15.00 05.00 Vinyl Toluene _____ _____ 15.00 15.00 05.00 Mod L 00.00 00.00 00.17 00.17 00.06 12* Cobalt 00.30 00.30 00.30 00.30 00.30 16* Potassium 00.20 00.20 00.20 00.20 00.20 Dimethyl Acetoacetamide 00.30 00.30 00.30 00.30 00.30 Resin Properties Gel Time, min:sec 48:00 27:55 33:52 25:10 30:40 Interval, min:sec 10:49 05:01 07:07 03:51 05:23 Exotherm, β F 229 239 244 291 258 Viscosity, cps § 75°F 1,280 1,085 560 650 930 Barcol-45 minutes 00.0 31.7 00.0 00.0 26.6 -one hour 00.0 47.3 29.7 47.0 48.7 -two hours 00.0 48.6 45.6 50.8 51.0 -three hours 00.0 48.2 45.9 49.8 51.1 -four hours 00.0 48.6 46.0 50.3 51.2 -24 hours 38.2 48.4 47.2 50.7 51.5 1162 Emissions, G/M2 2.4 6.1 3.6 4.2 3.0 Emissions, min:sec 60:55 36:42 53:46 29:15 36:18 Properties of a Clear Castinσ HDT, # F 129 138 138 159 163 Tensile Strength, psi 9,290 8,980 9,580 9,140 6,050 Ten Modulus, 10-5 psi 0.451 0.481 0.485 0.544 0.587 Elongation, * 3.10 2.40 2.50 2.00 1.20 Flexural Strength, psi 14,400 >16,130 18,400 19,660 17,150 Flex Modulus, 10-5 psi 0.488 0.520 0.662 0.664 0.633 Water Absorption § 150 β F 24 hours 1.06 1.08 1.07 0.95 1.07 seven days 2.43 2.19 1.78 1.84 2.06 TABLE III Low Voc Laminating Resins Based on General Purpose Polyester Polvmer Resin U-3 ZA V-3 ? Q-4 Composition Resin A 35.00 35.00 35.00 35.00 30.00 Sartomer 480 15.00 15.00 15.00 15.00 20.00 Sartomer 348 20.00 20.00 20.00 20.00 20.00 EG Dimethacrylate 15.00 10.00 10.00 30.00 Cyclohexyl Methacrylate 05.00 10.00 10.00 Vinyl Toluene 10.00 10.00 30.00 10.00 Mod L 00.13 00.06 00.20 00.12 00.10 12* Cobalt 00.30 00.30 00.30 00.30 16* Potassium 00.20 00.20 00.20 00.20 Dimethyl Acetoacetamide 00.30 00.30 00.30 00.30 Resin Properties Gel Time, min:sec 38:05 38:15 37:36 18:29 14:10 Interval, min:sec 06:07 07:37 09:49 04:11 4:38 Exotherm, *F 277 277 273 276 233 Viscosity, cps § 75 β F 790 710 382 426 400 Barcol-45 minutes 00.0 00.0 00.0 44.0 50.1 -one hour 37.0 32.2 39.9 48.0 51.9 -two hours 48.6 47.2 46.0 52.1 -three hours 48.5 47.6 46.2 _ 52.1 -four hours 48.5 47.8 46.9 _ * 52.1 -24 hours 48.5 48.7 46.9 51.0 52.1 1162 Emissions, G/M2 7.3 2.4 1.8 6.1 0.6 Emissions, min:sec 44:22 48:20 51:35 16:00 Properties of a Clear Castinα HDT, β F 136 138 138 142 210 Tensile Strength, psi 10,120 10,370 9,500 9,635 5,660 Ten Modulus, 10-5 psi , 0.489 0.540 0.501 0.565 0.516 Elongation, * 2.70 2.60 2.30 2.70 1.30 Flexural Strength, psi 18,750 19,410 >19,150 16,889 14,550 Flex Modulus, 10-5 psi 0.444 0.508 Water Absorption @ 150" F 24 hours 1.06 1.04 0.81 1.19 seven days 1.78 1.87 1.43 1.65 TABLE IV RESIN - A2 C2 g 2 ΔJ-_ Resin A - 60.00 60.00 40.00 35.00 35.00 Sartomer CD480 15.00 15.00 15.00 Sartomer 348 — — — 20.00 20.00 20.00 EG Dimethacrylate 25.00 10.00 20.00 Vinyl Toluene 40.00 10.00 Cyclohexyl Methacrylate 10.00 Divinyl Benzene — — — — — - 10.00 Styrene - 40.00 Mod L - 0.20 0.22 0.06 0.12 0.12 RESIN PROPERTIES Gel time, min:sec - 12:59 13:17 21:18 18:29 11:30 Interval, min:sec - 5:58 6:54 4:32 4:il 3:26 Exotherm peak, "F 345 324 249 276 294 Viscosity, cps, 75 β F - 315 340 1,390 426 624 1162 Emissions, G/M2 - 31.5 20.6E 3.6 6.1 9.7 Barcol hardness 45 minutes - 45 42 47 44 52 One hour 45 43 50 48 53 24 hours 49 49 52 51 54 CLEAR CASTING PROPERTIES Tensile strength, psi- 9,308 7,555 8,069 9,635 8,176 Ten. modulus, 10-5psi- 0.549 0.534 0.466 0.565 0.575 Elongation, * - 1.9 1.6 .3.2 2.7 1.9 Flexural strength,psi- 16,008 15,317 10,475 16,889 15,780 Flex modulus, 10-5psi- 0.586 0.573 0.322 0.444 0.482 Heat deflect. temp,'F- 144 138 169 142 147 Water absorption. * at 15 T One day - 0.89 0.91 1.01 1.19 1.26 7 days - 1.89 1.89 2.12 1.65 1.76 E - This value was estimated based on the di ference in results caused by using different end points for the 1162 test. A - The surfaces of the test specimens were alligatored. This indicates a more severe problem than the weight gain indicates. 1'ABLE V Low VOC Laminating Resins Based : on General Purpose Polyester Polvmer Resin E-4 V-3 F-4 G-3 D-4 __A ς ff ositi«?n Resin A 35.00 35.00 35.00 35.00 35.00 35.00 Sartomer 480 15.00 15.00 15.00 15.00 15.00 15.00 Sartomer 348 20.00 20.00 20.00 20.00 20.00 20.00 EG Dimethacrylate -_ 10.00 10.00 Cyclohexyl Methacrylate _____ _____ 15.00 15.00 10.00 10.00 Styrene 30.00 15.00 10.00 Vinyl Toluene 30.00 15.00 10.00 Mod L 00.10 00.20 00.05 00.17 00.00 00.06 12* Cobalt 00.30 00.30 00.30 00.30 00.30 00.30 16* Potassium 00.20 00.20 00.20- 00.20 00.20 00.20 Dimethyl Acetoacetamide 00.30 00.30 00.30 00.30 00.30 00.30 Resin Properties Gel Time, min:sec 29:20 37:36 31:47 33:52 19:45 38:15 Interval, min:sec 10:35 09:49 11:35 07:07 10:15 07:37 Exotherm, *F 301 273 220 244 231 277 Viscosity, cps % 75*F 360 382 1570 560 990 710 Barcol-45 minutes 00.0 00.0 00.0 00.0 36.0 00.0 -one hour 39.6 39.9 00.0 29.7 47.2 32.2 -two hours 43.9 46.0 41.6 45.6 47.8 47.2 -three hours 46.4 46.2 43.9 45.9 48.2 47.6 -four hours 46.7 46.9 44.3 46.0 48.6 47.8 -24 hours 46.9 46.9 43.9 47.2 48.5 48.7 1162 Emissions, G/M2 9.7 1.8 4.8 3.6 3.0 2.4 Emissions, min:sec 46:12 51:35 50:00 53:46 36:10 48:20 Properties of a Clear Casting HDT, *F 147 138 127 138 133 138 Tensile Strength, psi 7,610 9,500 8,930 9,580 7,950 10,370 Ten Modulus, 10-5 psi 0.442 0.501 0.452 0.485 0.454 0.540 Elongation, * 2.00 2.30 2.70 2.50 2.00 2.60 Flexural Strength, psi >19,220 >19,150 >17,060 1 18,400 14.98C 1 19,410 Flex Modulus, 10-5 psi 0.536 0.509 0.662 0.545 ___— Water Absorption θ 150* F 24 hours 1.07 0.81 1.30 1.07 1.22 1.04 seven days 1.81 1.43 2.16 1.78 2.09 1.87 TABLE V (cont'd) Low VOC Laminating Resins Based on General Purpose Polyester Polvmer Resin H-4 V-? G-4. H-3 Controls Composition Resin A 35.00 35.00 35.00 35.00 60.00 60.00 Sartomer 480 15.00 15.00 15.00 15.00 _____ Sartomer 348 20.00 20.00 20.00 20.00 _____ EG Dimethacrylate 15.00 15.00 15.00 15.00 Cyclohexyl Methacrylate 05.00 05.00 _____ _____ _ Styrene 10.00 15.00 40.00 40.00 Vinyl Toluene 10.00 15.00 _ _ Mod L 00.00 00.13 00.05 00.17 00.10 00.30 12* Cobalt 00.30 00.30 00.30 00.30 00.30 00.30 16* Potassium 00.20 00.20 00.20 00.20 00.20 00.20 Dimethyl Acetoacetamide 00.30 00.30 00.30 00.30 00.30 00.30 Resin Properties Gel Time, min:sec 09:22 38:05 15:26 25:10 05:00 23:22 Interval, min:sec 0 :27 06:07 03:19 03:51 06:02 Exotherm, *F 239 277 268 291 296 Viscosity, cps β 75*F 910 790 1100 650 440 440 Barcol-45 minutes 46.1 00.0 44.5 00.0 41.9 -one hour 48.7 37.0 48.1 47.0 44.8 -two hours 49.2 48.6 50.0 50.8 45.4 -three hours 49.7 48.5 50.5 49.8 45.5 -four hours 49.6 48.5 50.6 50.3 45.9 -24 hours 50.4 48.5 50.3 50.7 46.2 1162 Emissions, G/M2 1.2 7.3 2.4 4.2 12.7 24.2 Emissions, min:sec 13:43 44:22 21:43 29:15 20:14 23:22 Properties of a Clear Casting HDT, *F 143 136 147 159 144 Tensile Strength, psi 7,410 10,120 6,160 9,140 8,040 Ten Modulus, 10-5 psi 0.473 0.489 0.521 0.544 0.478 Elongation, * 1.80 2.70 1.50 2.00 1.80 Flexural Strength, psi 16,030 18,750 15,950 19,660 15,070 Flex Modulus, ' 10-5 psi 0.569 0.599 0.664 0.598 Water Absorption β 150'F 24 hours 1.23 1.06 1.17 0.95 01 .01 seven days 2.14 1.78 2.14 1.84 11 .11 Accordingly, our invention comprises compositions comprising (a) the base polyester polymer (resin) as described above and the alkoxylated bisphenol-A diacrylate or dimethacrylate in a ratio of 2:1 to 0.5:1 and (b) either (1) about 20-60%, based on the total of (a) and (b) of vinyl toluene or divinyl benzene or a combination thereof, (2) about 10% to about 60%, based on the total of (a) and (b), of either styrene or divinyl benzene or a combination thereof, or (3) about 20% to about 60%, based on the total of (a) and (b), of ethylene glycol dimethacrylate. In Tables I through V, the various "Sartomer" compositions, i.e. the ethoxylated bisphenol-A dimethacrylates, have 1 and 5 ethoxy groups on each side of the bisphenol-A; however, we may employ a single compound or compounds having any variation of combinations of ethoxy or propoxy groups from two to about 20 groups, preferably a total of 2 to 8 alkoxy groups.

Claims: Claims 1. A laminating resin composition characterized by low volatile emissions comprising (A) a base unsaturated polyester resin comprising glycols, unsaturated polycarboxylic acids or derivatives thereof, and, optionally, saturated dicarboxylic acids and (B) alkoxylated bisphenol-A diacrylate or dimethacrylate having at least two alkoxy groups, in a weight ratio of (A) to (B) of 2:1 to 0.5:1, and (C) about 20% to about 60% by weight, based on the total of components (A) and (B) of a compound of the formula where one H on the ring is substituted by CH 3 . 2. A laminating resin composition characterized by low volatile emissions comprising (A) a base resin comprising glycols, unsaturated polycarboxylic acids or derivatives thereof, and, optionally, saturated dicarboxylic acids and (B) alkoxylated bisphenol-A diacrylate or dimethacrylate having at least two alkoxy groups, in a weight ratio of (A) to (B) of 2:1 to 0.5:1, and (C) about 20% to about 60% by weight, based on the total of components (A) and (B) of ethylene glycol dimethacrylate. 3. A laminating resin composition characterized by low volatile emissions comprising (A) a base unsaturated polyester resin comprising glycols, unsaturated polycarboxylic acids or derivatives thereof, and, optionally, saturated dicarboxylic acids and (B) alkoxylated bisphenol-A diacrylate or dimethacrylate having at least two alkoxy groups, in a weight ratio of (A) to (B) of 2:1 to 0.5:1, and (C) about 10% to about 60% by weight, based on the total of components (A) and (B) of an ingredient comprising: (i) X% divinyl benzene; and (ii) 100-X% styrene, wherein X is 0-100. 4. Laminating resin composition of claims 1, 2, or 3 including from 1% to about 10%, based on the overall composition, of N-vinyl pyrrolidone. 5. Laminating resin composition of claims 1, 2, or 3 including from 1% to about 20%, based on the overall composition, of cyclohexyl methacrylate. 6. A laminating resin of claims 1, 2, or 3 wherein the weight ratio of (A) to (B) is about 1:1. 7. A laminating resin of claims 1, 2, or 3 characterized by volatile emissions measured by the test of Section 1162 of the Regulations of the South Coast (California) Air Quality District no greater than 20 grams per square meter. 8. Method of laminating a solid formed body without creating significant volatile emissions in the workplace comprising (a) providing a forming surface having a desired positive or negative shape, (b) providing a liquid mixture comprising (1) about two parts by weight unsaturated polyester resin, (2) about one part to about four parts by weight alkoxylated bisphenol-A diacrylate or dimethacrylate, (3) about 20% to about 60%, based on the total weight of (1) and (2), of a monomer of the formula where one H on the ring is substituted by CH 3 , and (4) an effective amount of a polymerization catalyst, (c) applying said mixture to said forming surface at ambient temperatures in layers while permitting said layers incrementally to polymerize, thereby building said shaped article without creating significant volatile emissions, and (d) removing the finished solid formed body from said forming surface. 9. Method of laminating a solid formed body without creating significant volatile emissions in the workplace comprising (a) providing a forming surface having a desired positive or negative shape, (b) providing a liquid mixture comprising (1) about two parts by weight unsaturated polyester resin, (2) about one part to about four parts by weight alkoxylated bisphenol-A diacrylate or dimethacrylate, (3) about 20% to about 60%, based on the total weight of (1) and (2), of ethylene glycol dimethacrylate, and (4) an effective amount of a polymerization catalyst, (c) applying said mixture to said forming surface at ambient temperatures in layers while permitting said layers incrementally to polymerize, thereby building said shaped article without creating significant volatile emissions, and (d) removing the finished solid formed body from said forming surface. 10. Method of laminating a solid formed body without creating significant volatile emissions in the workplace comprising (a) providing a forming surface having a desired positive or negative shape, (b) providing a liquid mixture comprising (1) about two parts by weight unsaturated polyester resin, (2) about one part to about four parts by weight alkoxylated bisphenol-A diacrylate or dimethacrylate, (3) about 20% to about 60%, based on the total weight of (1) and (2) , of an ingredient comprising: (i) 100-X% styrene; and (ii) X% divinyl benzene, wherein X is 0-100, and (4) an effective amount of a polymerization catalyst, (c) applying said mixture to said forming surface at ambient temperatures in layers while permitting said layers incrementally to polymerize, thereby building said shaped article without creating significant volatile emissions, and (d) removing the finished solid formed body from said forming surface. 11. Method of claims 8, 9, or 10 wherein the alkoxylated BPA is a dimethacrylate and has about 2 to about 20 alkoxy groups. 12. Method of claims 8, 9, or 10 wherein said mixture is applied by spraying. 13. Method of claim 8, 9, or 10 wherein said mixture includes glass fibers. 14. Method of claims 8, 9, or 10 wherein said alkoxy groups are ethoxy groups. 15. Method of claim 8 wherein said alkoxylated BPA dimethacrylate has from 2 to 8 alkoxy groups. 16. Method of claim 10 wherein X is 0. 17. Method of claim 10 wherein X is 100. 18. Method of claim 10 wherein said alkoxylated BPA dimethacrylate has from 2 to 10 alkoxy groups. 19. Method of making a shaped article comprising repeatedly applying to a form a liquid laminating resin of claims 1, 2, or 3 under polymerizing conditions, and permitting said resin to polymerize, thereby building said shaped article without emitting significant amounts of volatile monomers.

Inventors: BROWNELL GEORGE L, SMEAL THOMAS W, BROWNELL, GEORGE, L., SMEAL, THOMAS, W.
Applicants: ARISTECH CHEMICAL CORP, ARISTECH CHEMICAL CORPORATION
Application year: 1995
Main classification: C08L67
IPC codes: B32B27, B32B37, C08F283, C08L67