Performance of CHDA in polyester polyols for weatherable 2K polyurethane coatings.Polyurethane polyurethane Any of a class of very versatile polymers that are made into flexible and rigid foams, fibres, elastomers (elastic polymers), surface coatings, and adhesives. coatings are known for their durability and overall good balance of mechanical properties. Both acrylics and polyesters are used as polyols in two-component, solventborne polyurethane coatings. Polyester polyols containing isophthalic acid Isophthalic acid, or benzene-1,3-dicarboxylic acid, is an aromatic dicarboxylic acid, with formula C6H4(COOH)2. It is an isomer of phthalic acid and terephthalic acid. (PIA pi·a n. The pia mater. pi  al adj. ) weather extremely
well, but they have poor flexibility. Usually, a combination of a
flexible diacid, such as adipic acid a·dip·ic acid n. A white crystalline dicarboxylic acid, C6H11O4, that is derived from oxidation of various fats, slightly soluble in water and soluble in alcohol and acetone, and used especially in the manufacture of (AD), and PIA are used to achieve a hardness/flexibility balance in the coating. While improving flexibility, AD has an adverse effect on the beneficial properties of PIA, especially outdoor durability. CHDA (1,4-cyclohexanedicarboxylic acid) exhibits a unique balance of properties that are characteristic of linear aliphatic aliphatic /al·i·phat·ic/ (al?i-fat´ik) pertaining to any member of one of the two major groups of organic compounds, those with a straight or branched chain structure. al·i·phat·ic adj. and aromatic aromatic /ar·o·mat·ic/ (ar?o-mat´ik) 1. having a spicy odor. 2. in chemistry, denoting a compound containing a ring system stabilized by a closed circle of conjugated double bonds or nonbonding electron pairs, e.g. diacids. These properties include rapid reactivity, a hardness/flexibility balance, and resistance to chemicals and humidity. [ILLUSTRATION OMITTED] The objective of these experiments was to evaluate the performance, particularly outdoor durability, of high-solids, two-component, pigmented pigmented /pig·ment·ed/ (pig-ment´id) colored by deposit of pigment. pig·ment·ed adj. Colored as the result of a deposit of pigment. polyurethane coatings containing CHDA. Experimental variables included the CHDA/PIA molar molar /mo·lar/ (mo´lar) 1. pertaining to a mole of a substance. 2. a measure of the concentration of a solute, expressed as the number of moles of solute per liter of solution. Symbol M, , or mol/L. ratio in a model polyester polyol, coating crosslink density, and effect of a commonly used ultraviolet An invisible band of radiation at the upper end of the visible light spectrum. With wavelengths from 10 to 400 nm, ultraviolet starts at the end of visible light and ends at the beginning of X-rays. The primary source of ultraviolet light is the sun. absorber (UVA) and hindered amine Hindered amines are chemical compounds conatining an amine functional group surrounded by a crowded steric environment. They have uses such as gas scrubbing, as stabilizers against light-induced degradation of polymers, and as reagents for organic synthesis. light stabilizer stabilizer: see airplane. (HALS) package. Comparisons were made to control polyester polyols containing AD/PIA and commercially available acrylic polyols marketed for exterior applications. Responses included coating viscosity, cured film glass transition temperature The glass transition temperature is the temperature below which the physical properties of amorphous materials vary in a manner similar to those of a solid phase (glassy state), and above which amorphous materials behave like liquids (rubbery state). , gloss, hardness, flexibility, acid resistance, and Florida weathering over a three and a half year period. INTRODUCTION Polyurethane coatings are known for their durability and overall good balance of mechanical properties. These include long-term weathering, flexibility, and resistance to chemicals, abrasions, scratching, chipping, and stress. Consequently, polyurethane coatings are used in such demanding markets (1) as automotive, transportation, maintenance, and aerospace. Both acrylics and polyesters are used as polyols designated under ASTM ASTM abbr. American Society for Testing and Materials D 16 as Type V systems. (2) These are two-component, solventborne, polyol polyisocyanate systems. For exterior applications, the triisocyanurate of 1,6-hexamethylene diisocyanate (1,6-HDI) is normally used as the crosslinker. Acrylics are known for their excellent outdoor durability, but they do not have a good balance of mechanical properties. Polyester polyols offer an excellent balance of mechanical properties, but they do not weather as well as acrylics. To improve outdoor durability, UVA (ultraviolet absorber) and HALS (hindered amine light stabilizer) additives are commonly employed. (3) Polyester polyols containing isophthalic acid (PIA) weather extremely well (4) and have good stain, chemical, humidity, and corrosion resistance relative to aliphatic diacids. However, they have poor flexibility. Usually, a combination of a flexible diacid, such as adipic acid (AD), and PIA are needed to achieve a balance of flexibility and hardness in the coating. While improving flexibility, AD has an adverse effect on the beneficial properties of PIA, particularly weathering. (4) CHDA (1,4-cyclohexanedicarboxylic acid) exhibits a unique combination of linear aliphatic and aromatic diacid character. Movement of the cyclohexane cyclohexane (sī'kləhĕk`sān), C6H12, colorless liquid hydrocarbon. It is a cyclic alkane that melts at 6°C; and boils at 81°C;. It is nearly insoluble in water. ring between boat and chair conformations (Figure 1) imparts flexibility like a linear aliphatic diacid. The 1,4-substitution of acid groups maximizes this movement. In addition, it allows the close packing of resin chains to impart hardness like an aromatic diacid. Consequently, CHDA offers a balance of properties not obtained from aromatic diacids, linear aliphatic diacids, or a combination of the two. These properties (5) include: * Rapid reactivity and low resin color like AD * Resin hydrolytic hy·drol·y·sis n. Decomposition of a chemical compound by reaction with water, such as the dissociation of a dissolved salt or the catalytic conversion of starch to glucose. stability better than either PIA or AD * A hardness/flexibility balance not obtained by either PIA or AD alone * The chemical, detergent detergent (dētûr`jənt, dĭ–), substance that aids in the removal of dirt. Detergents act mainly on the oily films that trap dirt particles. , stain, and corrosion resistance of PIA * Humidity resistance better than AD The performance of CHDA in polyester-melamine thermoset A polymer-based liquid or powder that becomes solid when heated, placed under pressure, treated with a chemical or via radiation. The curing process creates a chemical bond that, unlike a thermoplastic, prevents the material from being remelted. See thermoplastic. coatings has been well documented. (6,7) The objective of these experiments was to evaluate the performance, particularly outdoor durability, of two-component, pigmented polyurethane coatings containing CHDA. [FIGURE 1 OMITTED] EXPERIMENTAL Design The factors selected for evaluation included: (1) level of CHDA in the diacid segment of a model polyester polyol, (2) effect of coating crosslink density on performance of a 1/1 molar CHDA/PIA polyol, and (3) polyester performance relative to commercially available acrylic controls. The effect of UVA and HALS additives on coating performance was evaluated within each group. The model polyester polyols consisted of neopentyl glycol glycol (glī`kōl), dihydric alcohol in which the two hydroxyl groups are bonded to different carbon atoms; the general formula for a glycol is (CH2)n(OH)2. (NPG NPG Nature Publishing Group (Macmillan Publishers, Ltd) NPG National Portrait Gallery (UK) NPG NIOSH Pocket Guide to Chemical Hazards NPG New Power Generation (Prince) )/trimethylol propane propane, CH3CH2CH3, colorless, gaseous alkane. It is readily liquefied by compression and cooling. It melts at −189.9°C; and boils at −42.2°C;. (TMP TMP (thymidine monophosphate): see thymine. )/diacid. The diacid segment was varied from 67% CHDA to 100% PIA. Two AD/PIA controls were included. These polyols had a hydroxyl hydroxyl /hy·drox·yl/ (hi-drok´sil) the univalent radical OH. hy·drox·yl n. The univalent radical or group OH, a characteristic component of bases, certain acids, phenols, alcohols, carboxylic functionality of 3.5 and a number average molecular weight of 800 (hydroxyl equivalent weight of 229) to evaluate the effect of the diacid component at constant crosslink density. The effect of coating crosslink density on the performance of polyols containing a constant 1/1 molar ratio of CHDA/PIA in the diacid segment was evaluated. The hydroxyl equivalent weight (OH EW = 343 and 229) of the polyol composition was varied by adjusting the molecular weight and functionality of the resins. The design parameters for the polyester polyols are listed in Table 1. Because acrylic polyols are known for their exterior durability, two commercially available acrylic controls were selected for comparison to the polyesters. They included Joncryl 906 (Johnson Polymer) and Macrynal SM 515 (Cytec Surface Specialties). The Joncryl acrylic polyol is marketed for high performance maintenance and transportation coatings. (8) The Macrynal SM 515 is suggested for automotive refinish re·fin·ish tr.v. re·fin·ished, re·fin·ish·ing, re·fin·ish·es To put a new finish on (furniture). re·fin topcoat, maintenance, and transportation applications. (9) Some coatings for exterior applications do not require the use of stabilizers, while others do. Thus, coating performance was evaluated without and with a UVA/HALS stabilizer package. The stabilizer package consisted of 2 wt% Tinuvin 1130 and 1 wt% Tinuvin 292 based on binder binder: see combine. An earlier Microsoft Office workbook file that let users combine related documents from different Office applications. The documents could be viewed, saved, opened, e-mailed and printed as a group. solids. Tinuvin 1130 is a benzotriazole-based liquid ultraviolet absorber, (10) and Tinuvin 292 is a tertiary amine-based liquid hindered amine light stabilizer. (11) These were supplied by Ciba and are recommended for automotive and industrial coatings An industrial coating is a paint or coating defined by its protective, rather than its aesthetic properties, although it can provide both. The most common use of industrial coatings is for corrosion control of steel or concrete. . Coating responses included Brookfield viscosity, hardness (pencil & Konig pendulum), flexibility (impact resistance), sulfuric acid sulfuric acid, chemical compound, H2SO4, colorless, odorless, extremely corrosive, oily liquid. It is sometimes called oil of vitriol. Concentrated Sulfuric Acid resistance (uncovered), cured coating film [T.sub.g] (unstabilized clear film only), and Florida weathering (20[degrees] gloss retention) over a three and a half year period. Resin Processing and Properties The polyester resins Polyester Resin - Unsaturated Polyester Resin. The term generally used for unsaturated (means containing chemical double bonds) resins formed by the reaction of dibasic organic acids and polyhydric alcohols, basic component of SMC/BMC. were prepared in a one-liter reaction kettle equipped with a heating mantle Heating mantle is a term for certain pieces of laboratory equipment used to apply heat to containers, as an alternative to other forms of heated bath. In contrast to other heating devices, such as hotplates or bunsen burners, glassware containers may be placed in direct contact with the , mechanical stirrer, thermocouple, nitrogen blanket, steam-jacketed partial condenser condenser Device for reducing a gas or vapour to a liquid. Condensers are used in power plants to condense exhaust steam from turbines and in refrigeration plants to condense refrigerant vapours, such as ammonia and Freons. , condensate condensate, matter in the form of a gas of atoms, molecules, or elementary particles that have been so chilled that their motion is virtually halted and as a consequence they lose their separate identities and merge into a single entity. trap, and a water-cooled total condenser. Raw materials were charged into the reactor and the temperature increased to form a homogenous homogenous - homogeneous melt. Agitation agitation /ag·i·ta·tion/ (aj?i-ta´shun) excessive, purposeless cognitive and motor activity or restlessness, usually associated with a state of tension or anxiety. Called also psychomotor a. was started and the temperature increased until water evolution began, and then was raised 10[degrees]C every 30 minutes until a maximum temperature of 230[degrees]C was reached. The reaction mixture was held at 230[degrees]C until a final acid value of 10 [+ or -] 2 mg KOH/g resin. The resin was cooled and poured into a clean, unlined metal can. The acrylic polyols were used as supplied from the manufacturer. Determined resin properties for the polyester polyols are listed in Table 2 as well as the hydroxyl number of the acrylic controls. Coating Formulation, Application, and Testing White-pigmented coatings were prepared from the polyols listed in Table 2 and crosslinked with the triisocyanurate of 1,6-hexanediisocyanate at a 1.1:1 NCO NCO abbr. noncommissioned officer NCO noncommissioned officer NCO n abbr (Mil) (= noncommissioned officer) → Uffz. :OH ratio. The coatings were formulated without and with the UVA/HALS stabilizer package. The coating formulation is listed in Table 3. The pigment pigment, substance that imparts color to other materials. In paint, the pigment is a powdered substance which, when mixed in the liquid vehicle, imparts color to a painted surface. loading was adjusted to give a constant pigment volume concentration (PVC PVC: see polyvinyl chloride. PVC in full polyvinyl chloride Synthetic resin, an organic polymer made by treating vinyl chloride monomers with a peroxide. ). A homogenizer A laboratory equipment for the homogenization of various types of material, such as tissue, plant, food, soil, and many others. Many different models have been developed using various physical technologies for the disruption. was used to thoroughly disperse disperse /dis·perse/ (dis-pers´) to scatter the component parts, as of a tumor or the fine particles in a colloid system; also, the particles so dispersed. dis·perse v. 1. the pigment in the resin. The solvent, catalyst, flow aid, and stabilizers (as needed as needed prn. See prn order. ) were then added and thoroughly mixed. The crosslinker was added and mixed right before viscosity determination and subsequent application to the substrate. Coatings were applied to iron phosphate-treated Bonderite 1000 22 gauge polished steel test panels using a wire-wrapped drawdown Drawdown The peak to trough decline during a specific record period of an investment or fund. It is usually quoted as the percentage between the peak to the trough. Notes: bar. Clear films for [T.sub.g] determination were coated onto glass microscope slides and cured along with the pigmented coatings. All were force-dried at 80[degrees]C for 45 min followed by one week of ambient Surrounding. For example, ambient temperature and humidity are atmospheric conditions that exist at the moment. See ambient lighting. aging before testing. [FIGURE 2 OMITTED] [FIGURE 3 OMITTED] [FIGURE 4 OMITTED] Coating viscosity was determined with a Brookfield Model DV-II viscometer viscometer Instrument for measuring the viscosity (resistance to internal flow) of a fluid. In one type, the time taken for a given volume of fluid to flow through an opening is recorded. equipped with a small sample adapter A device that allows one system to connect to and work with another. An adapter is often a simple circuit that converts one set of signals to another; however, the term often refers to devices which are more accurately called "controllers. . Spindle spindle: see spinning. A rotating shaft in a disk drive. In a fixed disk, the platters are attached to the spindle. In a removable disk, the spindle remains in the drive. Laptops use spindle designations to indicate the number of built-in drives. #27 was used with the LV setting. The clear films were removed from the glass slides for [T.sub.g] analysis with a DuPont 2100 DSC (1) (Digital Signal Controller) A microcontroller and DSP combined on the same chip. It adds the interrupt-driven capabilities normally associated with a microcontroller to a DSP, which typically functions as a continuous process. See microcontroller and DSP. at a heating rate of 20[degrees]C/min. Specular spec·u·lar adj. Of, resembling, or produced by a mirror or speculum. spec u·lar·ly adv.Adj. 1. gloss was measured with a BYK-Gardner glossmeter (ASTM D 523). Resistance to acid (50% [H.sub.2]S[O.sub.4]) was performed by spot test, uncovered, under ambient conditions for 24 hr (ASTM D 1308). Ratings are based on a scale of 1 to 5 with 5 indicating no effect and 1 indicating total failure. Hardness was determined by pencil test Pencil test has multiple meanings.
Florida Weathering Outdoor exposure testing was performed at the South Florida Test Service Everglades Test Facility. Panels were placed at a 5[degrees] inclination facing south in a black box. Every three months the panels were washed and gloss and color readings taken. Panels were removed from testing when the 20[degrees] gloss retention reached 30%. Only the 20[degrees] gloss retention of the coatings is presented since it is the most sensitive and instructive in·struc·tive adj. Conveying knowledge or information; enlightening. in·struc tive·ly adv. response. Again, the
coatings have been divided into three groups based on the factor being
studied. Figures 2-6 show the effect of varying the diacid composition
while keeping the hydroxyl equivalent weight of the polyester constant.
Figure 7 shows the effect of coating crosslink density on the 1/1 molar
CHDA/PIA polyol. Weathering of the acrylic controls is presented in
Figure 8. Unstabilized and stabilized coating performance is shown
within each group. Finally, select coatings from each group are
consolidated onto one graph for a head-to-head comparison in Figure 9.
RESULTS AND DISCUSSION Diacid Comparison The crosslink density of the coatings was held constant by keeping the molecular weight and functionality of the polyester polyols constant (hydroxyl equivalent weight of 229). Differences observed between the coatings can then be attributed to the substituted diacid. Table 4 shows that CHDA reduces coating viscosity, but not quite as much as AD. As PIA is replaced with more modifying diacid, the coating [T.sub.g] is lowered. However, CHDA does not lower the coating [T.sub.g] as much as AD. At 50 mole % replacement of PIA, CHDA lowers the [T.sub.g] by only 4[degrees]C relative to 19[degrees]C for AD. A combination of PIA and CHDA provides slightly better gloss than PIA and AD. Acid resistance is lowered as PIA is replaced with either modifying diacid. However, CHDA provides better acid resistance than AD. Table 5 shows that all of the coatings exhibited good hardness with little to no variation in pencil hardness or KPH. In impact testing, CHDA behaves like AD to greatly improve flexibility, whereas PIA alone is very brittle (jargon) brittle - Said of software that is functional but easily broken by changes in operating environment or configuration, or by any minor tweak to the software itself. Also, any system that responds inappropriately and disastrously to abnormal but expected external stimuli; e. . Addition of the UVA/HALS stabilizer package affects coating viscosity, impact resistance, and acid resistance. Stabilized coatings containing CHDA were lower in viscosity than the unstabilized ones. But the PIA coating and those containing AD increased in viscosity. Stabilized coatings had better impact resistance than their unstabilized counterparts. Although acid resistance was slightly lower in the stabilized coatings, hardness and gloss remained the same. Results indicate the UVA/HALS stabilizers soften or plasticize plas·ti·cize tr. & intr.v. plas·ti·cized, plas·ti·ciz·ing, plas·ti·ciz·es To make or become plastic. plas the coatings. Figures 2-4 show the outdoor durability of the CHDA/PIA polyols relative to the all PIA control. Replacing PIA with any level of CHDA reduces the outdoor durability of the polyol in unstabilized coatings. Their gloss retention is dramatically improved with the addition of the UVA/HALS stabilizers. A one-third to one-half replacement of PIA with CHDA provides gloss retention similar to the all PIA polyol in stabilized coatings (Figure 5). The AD/PIA controls showed similar results in the unstabilized coatings. Replacing PIA in the polyol with AD lowered the gloss retention of the unstabilized coatings similar to those shown for CHDA. Therefore, their results are not included. Figure 6 compares the gloss retention of the 1/1 and 1/2 CHDA/PIA polyols to that of the AD/PIA controls in stabilized coatings. Polyols containing CHDA weathered better than those containing AD, especially at 50% substitution of the PIA. In summary, CHDA lowers the viscosity of the PIA polyol similar to AD. It also provides a good balance of mechanical properties that cannot be attained by PIA alone. In addition, outdoor durability in stabilized coatings is maintained up to a 50 mole % replacement of PIA relative to AD. Effect of Crosslink Density Changes in crosslink density can impact the mechanical properties and outdoor durability of a coating. The 1/1 CHDA/PIA polyol was evaluated at 800 and 1200 number average molecular weight and functionality of 3.5 (hydroxyl equivalent weight of 229 and 343, respectively) to observe the effect of crosslink density on the coating. [FIGURE 5 OMITTED] [FIGURE 6 OMITTED] [FIGURE 7 OMITTED] [FIGURE 8 OMITTED] Table 4 shows that coating viscosity was lower for the higher equivalent weight polyol. This may be due to the higher hydroxyl number of the lower equivalent weight polyol (229) contributing to more hydrogen bonding hydrogen bonding Interaction involving a hydrogen atom located between a pair of other atoms having a high affinity for electrons; such a bond is weaker than an ionic bond or covalent bond but stronger than van der Waals forces. . As expected, the coating [T.sub.g] was higher for the lower equivalent weight polyol (higher crosslink density coating). Gloss was not affected by varying the polyol equivalent weight. The acid resistance improved as the equivalent weight increased, or with more polyol between crosslink sites. Surprisingly, the impact resistance decreased as the polyol equivalent weight increased (Table 5). The impact resistance may be influenced by the higher level of flexible isocyanate i·so·cy·a·nate n. Any of a family of nitrogenous chemicals that are used in industry and can cause respiratory disorders, especially asthma, if inhaled. crosslinker in the coating at higher hydroxyl number. Hardness was similar for each. [FIGURE 9 OMITTED] Again, results indicate the stabilizers soften or plasticize the films as shown by the lower acid resistance and increased impact resistance of the stabilized coatings. Figure 7 shows the effect of crosslink density and the stabilizers on the gloss retention of these coatings. Weathering of the unstabilized coatings is similar regardless of crosslink density. However, the stabilizers greatly improve weathering and differentiate the two polyols. Of significance is that the stabilized coating with the lowest crosslink density (highest equivalent weight polyol) retained better than 50% of its gloss after 42 months exposure. In summary, the equivalent weight of the 1/1 CHDA/PIA polyol could be manipulated to change the mechanical properties and outdoor durability of the stabilized coatings. Polyester Versus Acrylic The polyester polyols had similar or better mechanical properties than either acrylic control (Tables 4 and 5). The coating viscosity of the Macrynal SM 515 was lower than any of the polyester coatings. The Joncryl 906 acrylic imparted the lowest cured film [T.sub.g] of all the polyols in the experiment. Gloss and acid resistance was similar for both, but the polyesters had a much better hardness/flexibility balance compared to the acrylics. The stabilized coatings made from the acrylic controls were lower in viscosity and exhibited improved KPH relative to their unstabilized counterparts. Their impact resistance was not improved as was observed for the polyesters. Gloss retention of the commercial acrylic polyols is presented in Figure 8. In the unstabilized coatings, the Macrynal SM 515 weathered slightly better than the Joncryl 906 over the first 18 months. Addition of the stabilizers equalized their rate of gloss loss. For each polyol in the experiment, the outdoor durability of the stabilized coating was better than its unstabilized counterpart. Stabilizers clearly improve the gloss retention of each coating. The Florida weathering results for select stabilized coatings are presented in Figure 9 for comparison. The 1/1 AD/PIA polyol weathered worse than the acrylic controls. The PIA polyol and those containing 1/1 CHDA/PIA outperformed the acrylic controls. It is interesting that the 1/1 CHDA/PIA polyol with an equivalent weight of 343 out-weathered all of the polyols in the experiment. In summary, PIA imparts excellent outdoor durability to polyester polyols for polyurethane coatings. But like an acrylic, it lacks a balance of hardness and flexibility. A 1/1 molar CHDA/PIA polyol gives a good balance of mechanical properties and outdoor durability over commercially available acrylic polyols. Color Stability and Appearance In addition to gloss, color measurements were made over the course of outdoor exposure. All of the coatings exhibited excellent color retention since none exceeded a 1 [DELTA]E unit color shift. Although gloss decreased, there was very little rust and very little dirt pick-up upon inspection of the coatings after Florida exposure. CONCLUSIONS In polyester polyols for polyurethane coatings, CHDA strikes a balance in mechanical properties and outdoor durability. The balance may be attributed to its unique cycloaliphatic structure and 1,4-substitution. Results showed that replacing 33-50 mole % of PIA with CHDA in the polyol improves coating flexibility, and maintains coating [T.sub.g] while providing a better hardness/flexibility balance and acid resistance than AD. A UVA/HALS stabilizer package benefited all of the polyols--both polyesters and acrylics--evaluated. Stabilizers greatly improved the weathering of polyols containing CHDA and are essential for long-term durability. In stabilized coatings, CHDA provides an excellent balance of good weathering and physical properties not achieved by PIA alone or PIA in combination with AD. Polyols modified with CHDA can be made that weather as well as or better than some acrylics. Changing the crosslink density of a stabilized coating containing 1/1 molar CHDA/PIA resulted in better than 50% 20[degrees] gloss retention after three and a half years of Florida weathering. The results suggest that the CHDA/PIA ratio and crosslink density may be further optimized to maximize weatherability. Consequently, there may be opportunity to improve the mechanical properties of acrylic polyols with CHDA-polyester blends without compromising outdoor durability. ACKNOWLEDGMENTS The author would like to thank Prof. Dean C. Webster of North Dakota State University North Dakota State University, at Fargo; land-grant and state supported; coeducational; chartered and opened 1890 as North Dakota Agricultural College, achieved university status in 1960. and Mr. Allen L. Crain of Eastman Chemical Company Eastman Chemical Company is a United States based chemical company, engaged in the manufacture and sale of chemicals, plastics and fibers. Eastman has 16 manufacturing sites in 10 countries, supplying its products throughout the world. , Technology Division, for their contributions to the successful completion of this work. References (1) Linak, E., Dubois, F., and Kishi, A., "Urethane urethane (yoor´ithān´), n ethyl carbamate used as an anesthetic agent for laboratory animals, formerly used as a hypnotic in humans. Surface Coatings Surface coating A substance applied to other materials to change the surface properties, such as color, gloss, resistance to wear or chemical attack, or permeability, without changing the bulk properties. ," in CEH CEH Certified Ethical Hacker CEH Centre for Ecology and Hydrology CEH Comisión de Esclarecimiento Histórico CEH Centre for Environmental Health CEH Continuing Education Hour CEH Complex Electronic Hardware CEH Colorado Evidentiary Hearing Marketing Research Report [CD-ROM CD-ROM: see compact disc. CD-ROM in full compact disc read-only memory Type of computer storage medium that is read optically (e.g., by a laser). ], SRI International (company) SRI International - One of the world's largest contract research firms. Founded in 1946 in conjuction with Stanford University as the Stanford Research Institute, they later became fully independent and were incorporated as a non-profit organisation under U.S. , Menlo Park Menlo Park. 1 Residential city (1990 pop. 28,040), San Mateo co., W Calif.; inc. 1874. Electronic equipment and aerospace products are manufactured in the city. Menlo College and a Stanford Univ. research institute are there. 2 Uninc. , CA, pp. 30-48 (2000). (2) Hare hare, name for certain herbivorous mammals of the family Leporidae, which also includes the rabbit and pika. The name is applied especially to species of the genus Lepus, sometimes called the true hares. , C.H., Protective Coatings, Technology Publishing, Pittsburgh, pp. 247-248, 1994. (3) Wicks, Z.W., Jr., Organic Coatings Science and Technology, 2nd ed., Wiley, New York New York, state, United States New York, Middle Atlantic state of the United States. It is bordered by Vermont, Massachusetts, Connecticut, and the Atlantic Ocean (E), New Jersey and Pennsylvania (S), Lakes Erie and Ontario and the Canadian province of , pp. 89-96, 1999. (4) Heidt, P.C., Jones, T.E., Golob, D.J., Marsh, S.J., Elliott, M.L., and Moody, K.M., "Florida Weathering of Isophthalic Acid-Based, Melamine-Crosslinked Polyester Coatings," Proc. 27th International Waterborne, High-Solids, and Powder Coatings Powder coating is a type of dry coating, which is applied as a free-flowing, dry powder. The main difference between a conventional liquid paint and a powder coating is that the powder coating does not require a solvent to keep the binder and filler parts in a liquid suspension Symposium, New Orleans New Orleans (ôr`lēənz –lənz, ôrlēnz`), city (2006 pop. 187,525), coextensive with Orleans parish, SE La., between the Mississippi River and Lake Pontchartrain, 107 mi (172 km) by water from the river mouth; founded , LA, March 1-3, pp 295-307, 2000. (5) Eastman 1,4-CHDA Cycloaliphatic Diacid Intermediate for High-Performance Polyester Resins, Technical Bulletin No. N-341C, Eastman Chemical Company, Kingsport, TN, 2003. (6) Blount, W.W., Heidt, P.C., and Johnson, L.K., "The Importance of Film [T.sub.g] on the Performance of 1,4-CHDA-Based Industrial Coatings, Proc. 20th International Waterborne, High-Solids, and Powder Coatings Symposium, New Orleans, LA, 1993. (7) Heidt, P.C., "Cycloaliphatic-Based Thermoser Industrial Coatings," Proc. 21st International Waterborne, High-Solids, and Powder Coatings Symposium, New Orleans, LA, pp 365-385, 1994. (8) Joncryl 906 Acrylic Oligomer oligomer /ol·i·go·mer/ (ol´i-go-mer) a polymer formed by the combination of relatively few monomers. oligomer ( for High Solids Urethane Coatings, Technical Bulletin No. C112, Johnson Polymer, Sturtevant, W1, 2000. (9) Macrynal SM 515/70BAC BAC abbr. blood alcohol concentration , Technical Bulletin No. 1.0, Surface Specialties, Brussels, Belgium, 2001. (10) Ciba Tinuvin 1130 Light Stabilizer, Technical Bulletin Ed. 28.07.99, Ciba, Basle, Tarrytown, NY, 1999. (11) Ciba Tinuvin 292 Light Stabilizer, Technical Bulletin Ed. 28.07.99, Ciba, Basle, Tarrytown, NY, 1999. by Stacey J. Marsh Eastman Chemical Company* Presented at the 32nd Annual International Waterborne, High-Solids, and Powder Coatings Symposium, February 2-4, 2005, in New Orleans, LA. *P.O. Box 1974, Kingsport, TN 37662.
Table 1 -- Experimental Polyester Polyols--Target Properties
Molar
Comparison Diacid Ratio [M.sub.n] [F.sub.OH] OH EW OH#
Diacid CHDA/PIA 2/1 800 3.5 229 245
Diacid CHDA/PIA 1/1 800 3.5 229 245
Diacid CHDA/PIA 1/2 800 3.5 229 245
Diacid -- control PIA 800 3.5 229 245
Diacid -- control AD/PIA 1/4 800 3.5 229 245
Diacid -- control AD/PIA 1/1 800 3.5 229 245
OH EW -- 229 CHDA/PIA 1/1 800 3.5 229 245
OH EW -- 343 CHDA/PIA 1/1 1200 3.5 343 164
Comparison AN
Diacid 10
Diacid 10
Diacid 10
Diacid -- control 10
Diacid -- control 10
Diacid -- control 10
OH EW -- 229 10
OH EW -- 343 10
Table 2 -- Determined Polyol Properties
Comparison Diacid Molar Ratio AN [M.sub.w] [M.sub.n]
Diacid CHDA/PIA 2/1 10 4415 1508
Diacid CHDA/PIA 1/1 9 4387 1557
Diacid CHDA/PIA 1/2 10 4182 1531
Diacid -- control PIA 10 3764 1536
Diacid -- control AD/PIA 1/4 11 3798 1483
Diacid -- control AD/PIA 1/1 11 4249 1523
OH EW -- 229 CHDA/PIA 1/1 9 4387 1557
OH EW -- 343 CHDA/PIA 1/1 11 8123 1995
Joncryl 906 -- -- -- -- --
Macrynal SM 515 -- -- -- -- --
Comparison [M.sub.w]/[M.sub.n] OH#
Diacid 2.93 163
Diacid 2.82 216
Diacid 2.73 220
Diacid -- control 2.45 208
Diacid -- control 2.56 221
Diacid -- control 2.79 206
OH EW -- 229 2.82 216
OH EW -- 343 4.07 169
Joncryl 906 -- 92
Macrynal SM 515 -- 150
Table 3 -- White Pigmented Coating Formulation
Pigment DuPont R-960 Ti[O.sub.2]
PVC 17%
NCO:OH 1.1:1
Crosslinker Bayer Desmodur N-3390 (triisocyanurate of 1,6-HDI
supplied as 90 wt% solids in mixed xylenes)
Catalyst Dibutyltin dilaurate (DBTDL) at 0.005 wt% based on
binder solids
BYK 320 flow aid 0.4 wt% based on binder solids
Solvent blend Xylene/MAK/EEP (45/45/10) Urethane grade Xylene and
MAK used
Stabilizers 2 wt% Ciba Tinuvin 1130 (UVA) & 1 wt% Tinuvin 292
(HALS) based on binder solids
Coating wt% solids 70
Substrate Bonderite 1000 22 gauge polished steel test panels
Application Wire-wrapped drawdown bar
Cure 45 min at 80[degrees]C followed by 1 week ambient
aging
Table 4 -- White Pigmented Coating Properties
Comparison Diacid Molar Ratio Stabilizer Viscosity(cps)
Diacid CHDA/PIA 2/1 No 296
Diacid CHDA/PIA 1/1 No 365
Diacid CHDA/PIA 1/2 No 320
Diacid -- control PIA No 374
Diacid -- control AD/PIA 1/4 No 260
Diacid -- control AD/PIA 1/1 No 243
Diacid CHDA/PIA 2/1 Yes 286
Diacid CHDA/PIA 1/1 Yes 248
Diacid CHDA/PIA 1/2 Yes 312
Diacid -- control PIA Yes 406
Diacid -- control AD/PIA 1/4 Yes 276
Diacid -- control AD/PIA 1/1 Yes 260
OH EW -- 229 CHDA/PIA 1/1 No 365
OH EW -- 343 CHDA/PIA 1/1 No 221
OH EW -- 229 CHDA/PIA 1/1 Yes 248
OH EW -- 343 CHDA/PIA 1/1 Yes 205
Joncryl 906 -- -- No 273
Macrynal SM 515 -- -- No 110
Joncryl 906 -- -- Yes 198
Macrynal SM 515 -- -- Yes 104
Initial Gloss(20[degrees]/
Comparison [T.sub.g]([degrees]C) 60[degrees])
Diacid 65.4 75/90
Diacid 72.6 74/91
Diacid 72.6 73/91
Diacid -- control 76.5 70/91
Diacid -- control 62.9 62/88
Diacid -- control 57.2 69/89
Diacid -- 78/91
Diacid -- 80/92
Diacid -- 79/92
Diacid -- control -- 77/93
Diacid -- control -- 77/91
Diacid -- control -- 72/90
OH EW -- 229 72.6 74/91
OH EW -- 343 64.0 81/92
OH EW -- 229 -- 80/92
OH EW -- 343 -- 86/94
Joncryl 906 51.5 70/88
Macrynal SM 515 68.0 85/94
Joncryl 906 -- 79/91
Macrynal SM 515 -- 82/94
Comparison [H.sub.2]S[O.sub.4]
Diacid 3
Diacid 3
Diacid 4
Diacid -- control 5
Diacid -- control 4
Diacid -- control 1
Diacid 3
Diacid 3
Diacid 3
Diacid -- control 3
Diacid -- control 3
Diacid -- control 2
OH EW -- 229 3
OH EW -- 343 5
OH EW -- 229 3
OH EW -- 343 3
Joncryl 906 3
Macrynal SM 515 4
Joncryl 906 2
Macrynal SM 515 3
Table 5 -- White Pigmented Coating Properties
Comparison Diacid Molar Ratio Stabilizer Pencil(cut) KPH
Diacid CHDA/PIA 2/1 No 3H 177
Diacid CHDA/PIA 1/1 No 3H 170
Diacid CHDA/PIA 1/2 No 3H 177
Diacid -- control PIA No 3H 181
Diacid -- control AD/PIA 1/4 No 3H 166
Diacid -- control AD/PIA 1/1 No 3H 172
Diacid CHDA/PIA 2/1 Yes 3H 171
Diacid CHDA/PIA 1/1 Yes 3H 182
Diacid CHDA/PIA 1/2 Yes 3H 180
Diacid -- control PIA Yes 3H 179
Diacid -- control AD/PIA 1/4 Yes 3H 179
Diacid -- control AD/PIA 1/1 Yes 3H 168
OH EW -- 229 CHDA/PIA 1/1 No 3H 170
OH EW -- 343 CHDA/PIA 1/1 No 3H 162
OH EW -- 229 CHDA/PIA 1/1 Yes 3H 182
OH EW -- 343 CHDA/PIA 1/1 Yes 3H 182
Joncryl 906 -- -- No 2H 147
Macrynal SM 515 -- -- No 3H 179
Joncryl 906 -- -- Yes 3H 154
Macrynal SM 515 -- -- Yes 3H 177
Comparison Impact (F/R, in,-lb)
Diacid 90/60
Diacid 160/160
Diacid 100/20
Diacid -- control 60/10
Diacid -- control 80/<10
Diacid -- control 160/160
Diacid 160/160
Diacid 160/160
Diacid 160/30
Diacid -- control 120/10
Diacid -- control 130/50
Diacid -- control 160/160
OH EW -- 229 160/160
OH EW -- 343 90/50
OH EW -- 229 160/160
OH EW -- 343 160/140
Joncryl 906 50/10
Macrynal SM 515 50<10
Joncryl 906 60/10
Macrynal SM 515 40/<10
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