Rhoplex WL-100 Emulsion Copolymer For High-Gloss Metal Coatings

Transcription

1 Page 1 of 14 Rhoplex WL-100 Emulsion Copolymer For High-Gloss Metal Coatings Table of Contents Introduction Key Features Typical Physical Properties Formulating Starting Point Formulations 1.5 PVC Black Gloss Paint 10 PVC Yellow Gloss Paint 17 PVC White Gloss Paint 35 PVC Reactive Pigment Containing Primer Material Safety Data Sheets Introduction Rhoplex WL-100 resin is an acrylic-styrene copolymer designed for high-gloss, high-doi (Distinctness of Image) waterborne metal coatings where an attractive appearance and corrosion protection are important considerations. The favorable colloidal stability (robustness) of Rhoplex WL-100 resin accommodates a broad range of formulation types and formulation process techniques, providing the formulator with a versatile binder for a variety of applications. Robustness, along with 50% weight solids, allows the formulator to achieve volume solids above conventional waterborne binders. Applications that are well suited for coatings based on Rhoplex WL-100 resin include transportation vehicles (rail car, truck chassis, etc.), various factory-applied items (boxes, tools, etc.), and structural steel. KEY FEATURES High gloss and DOI easily achieved Wide formulation latitude and applications Favorable formulation cost/performance balance Good corrosion control Can produce hard films Excellent adhesion to blasted hot-rolled and cold-rolled steels Adhesion to alkyd paints

2 Page 2 of 14 TYPICAL PHYSICAL PROPERTIES These properties are typical but do not constitute specifications. Appearance Milky-White Liquid Solids, % by weight 49% to 50% ph 8.5 to 9.5 Viscosity, Brookfield, cp 50 to 200 Wet Density, lbs./u.s. gal Dry Bulking Value, gal./lb MFFT, o C 48 FORMULATING Optimum application and dry film performance properties of a protective coating depend critically on the proper choice and level of formulation ingredients. The following formulation guidelines and sample paint formulations are intended to demonstrate the versatility of Rhoplex WL-100 resin, as well as to provide the formulator with information to expedite the evaluation of the product. Coalescents and Plasticizers The MFFT of Rhoplex WL-100 resin is well above (~48 o C) most application temperatures and consequently requires the use of coalescing solvents and plasticizers to form films with optimum physical properties. The type and level of coalescing solvents and plasticizers depends on the application and end use. Coalescing solvents found useful in formulations based on Rhoplex WL-100 resin include the partially water-soluble alkyl ethers of propylene and dipropylene glycols. A specific example is dipropylene n-butyl ether (Dowanol DPnB) used at about 25% (w/w) based on polymer solids (BOP) when used alone. Substantially reduced levels (=10% BOP) of DPnB can be used if a non-volatile water-immiscible plasticizer (see below) is part of the coalescing package. Dowanol DPnB and other partially and completely water-miscible, polymer-phase, (see DB below) coalescing solvents effectively interact and swell Rhoplex WL-100 latex particles. Latex particle swelling can provide a useful method of increasing application viscosity. Other examples of alkyl ethers of (di) propylene glycol include propylene glycol n-butyl ether (PnB) and dipropylene glycol n-propyl ether. However, due to the fast evaporation rate of PnB, inclusion of a slower evaporative coalescing solvent or non-evaporative plasticizer may be necessary for optimum film formation. To a much lesser degree, the completely water-soluble alkyl ethers of (di)ethylene glycol (e.g. Dowanol DB and EB) provide adequate film formation and require much higher (> 25% BOP) use levels for good film formation. In general DB (or EB) should be used as part of a coalescing package rather than alone. Other coalescing solvents found useful for coatings based on Rhoplex WL-100 resin include the alkyl acetates (n-alkyl or branched) and Texanol. Although very effective coalescing solvents for Rhoplex WL-100 resin, the nearly complete water immiscibility of Exxates 800 (and higher alkyl members of the Exxate family) and Texanol do not cause the same extent of latex

3 Page 3 of 14 particle swelling as Dowanol DPnB. The use of a permanent plasticizer(s) has been found to provide beneficial properties to coatings based on Rhoplex WL-100 resin. These include enhanced impact resistance, flexibility, and reduced surface dry time. Reduced surface dry time can be important in applications involving recoat, stencil application, and gloss and film clarity retention after exposure to water. Permanent plasticizers found useful in formulations based on Rhoplex WL-100 resin include Santicizer 160, dibutyl phthalate, and KP-140. Examples of the use of a permanent plasticizer can be found in the sample formulations. Pigments, Dispersants, Wetting Aids The choice and level of pigments, dispersants, and wetting aids can have a profound effect on the appearance and barrier properties of cured films. The sample formulations show that Rhoplex WL-100 resin can be formulated into coatings with a wide range of pigment levels (PVC) and types, including both inert and reactive pigments. The stability of Rhoplex WL-100 resin to shear allows the formulator, in some cases, to prepare pigment dispersions in the presence of resin. This potential advantage allows for paints with increased volume solids. Tamol 681 and Tamol 165 pigment dispersants at levels of approximately 0.75% to 2% on pigment solids have been found to produce coatings with a good balance of high gloss and good barrier properties. Pigment wetting, non-ionic, low-foaming surfactants, such as Triton CF-10, Igepal CTA-639W, and Surfynol 104A, have been used successfully to prepare pigment dispersions at levels of approximately 1 to 5 lbs./100 gal. of formulation. Preventing Flash Rust Low levels of aqueous solutions of ammonia benzoate and sodium nitrite can reduce or eliminate flash rust formation in a paint film under slow-drying conditions on steel. Typical use levels of a 15% aqueous solution of sodium nitrite are approximately 2 to 12 lbs./100 gal. of formulation. The formulator should evaluate the level of an anti flash-rust additive, since excessive levels can have negative effects on dry film performance. Deformers Various surface active ingredients used in waterborne paint formulations, such as dispersants, wetting aids, latex surfactants, and some coalescents may generate or stabilize foam during the manufacture or application of paint. In general, a defoamer should be evaluated for its effectiveness and long-term efficacy in each formulation, since the type and level of the surface-active ingredients will vary. Examples of defoaming agents found useful in formulations based on Rhoplex WL-100 resin are Byk -002, Byk-024, Tego Foamex 1488, and Dehydran Viscosity Control and Thickening Agents In some cases, paints based on Rhoplex WL-100 resin may not require the use of an external thickener. As mentioned previously, glycol ethers such as Dowanol DPnB and DB swell Rhoplex WL-100 latex particles, increasing their effective volume and increasing paint viscosity. This self thickening is highly dependent on formulation volume solids with higher volume solids showing the greatest response. The use of ammonia or other amines can further increase viscosity. However amines that evaporate slower than ammonia can reduce dry time and prolong or increase film water sensitivity. High molecular weight HEUR thickeners, such as Acrysol RM-12W are recommended for thick film applications to control sagging and mud cracking. Depending on other formulation ingredients, the rheology modifier level can vary from 1 to 20 lbs./100 gal. of paint with high levels of coalescent and surfactants requiring higher levels of thickener. Other HEUR thickeners

4 Page 4 of 14 found useful in formulations based on Rhoplex WL-100 resin include Acrysol RM-2020NPR for increasing viscosity at high shear and Acrysol RM-8W for increasing viscosity at medium shear rates. STARTING-POINT FORMULATIONS The following are examples of starting point formulations based on Rhoplex WL-100 resin. These formulations are not optimized for a specific application and are offered as a guide and a demonstration of the versatility of Rhoplex WL-100 resin. 1.5 PVC BLACK GLOSS PAINT BASED ON RHOPLEX WL-100 RESIN Ingredient Pounds Gallons Rhoplex WL Water Propylene Glycol Tego Foamex Ammonia (15%) Dibutyl Phthalate Dowanol DPnB Sodium Nitrite (15%) Water Carb Black Acrysol RM-8W Totals

5 Page 5 of 14 PROPERTIES OF 1.5 PVC BLACK GLOSS PAINT BASED ON RHOPLEX WL-100 RESIN 1 Total PVC 1.5% Volume Solids 38.35% Weight Solids 38.93% Density Viscosity Stability after C 8.64 lb./gal KU ok VOC (g/l) 222 Film Gloss (3.5-4 mil DFT) Film Gloss (3.5-4 mil DFT) After 800 hrs QUV-A 2 Film Gloss (3.5-4 mil DFT) After 800 hrs QUV-B and o and and DOI 90 Impact Resistance (3.5 to 4 DFT) (Direct/Indirect) in.-lbs. Salt Fog 100 hr. Exposure (ASTM B-117) (1.5 to 2 mil DFT on CRS 4 ) Salt Fog Exposure 7 day (ASTM B-117) (3.5 to 4 mil DFT on HRS 5 ) Adhesion 6 (DFT 3.5 to 4 mils) To CRS (Q-Panel Type R) To aged industrial alkyd paint Early Rust 7 150/150 No field damage. Some blisters formed along scribe. No field damage. A few blisters formed along scribe. No failure No failure No blister or rust formation Water Resistance (3.5 to 4 mil DFT) 24 Hour water immersion Film dulling hours condensation (40 C) cabinet exposure Film dulling Footnotes: 1. Unless otherwise stated, film cure was for 7 days at 25 C/50% relative humidity hours light 60 C followed by 4 hours 40 C hours light 60 C followed by 12 hours 40 C 4. Cold rolled steel. 5. Blasted hot rolled steel. 6. Cross-hatch tape test mil wet films 7.5 C/75% relative humidity for 6 hours followed by 24 hour exposure to water saturated cheese cloth. 8. A significant increase of film gloss retention following long term water exposure can be realized by replacing part of the evaporative co-solvent (DPnB in this case) with a plasticizer.

6 Page 6 of PVC YELLOW GLOSS PAINT BASED ON RHOPLEX WL-100 RESIN Ingredients Pounds Gallons Grind Water Tamol Ammonia (28%) Triton CF Byk Bayferrox Ti-Pure R Grind Sub-total Letdown Rhoplex WL Water Byk Aqueous Ammonia (14%) ph to ~9.2 Add Grind From Above Water Premix Water Ethanol Butyl Carbitol Dowanol DPnB Santicizer Premix Sub-total Premix Water Sodium Nitrite (15%) Acrysol RM-12W Premix Sub-total Totals

7 Page 7 of 14 PROPERTIES OF 10 PVC YELLOW GLOSS PAINT BASED ON RHOPLEX WL-100 RESIN 1 Total PVC 10% Volume Solids 35.4% Weight Solids Density Viscosity (initial) Viscosity (10 day heat 60ºC) Viscosity (After 5 freeze-thaw cycles) lb./gal. 90 KU 87 KU 103 KU VOC (g/l) 150 Film Gloss (3-4 mil DFT) Film Gloss (3-4 mil DFT) After 1081 hrs QUV-A o and o o and o DOI 80 Impact Resistance (Direct/Indirect) in.-lbs. >150/>150 Salt Fog Exposure (ASTM B-117) (2 mil DFT on CRS 3 ) 100 hours Salt Fog Exposure (ASTM B-117) (4 mil DFT on HRS 4 ) Minor rust formation Very few No. 7 blisters Adhesion 5 (DFT 3.5 to 4 mils) To CRS (Q-Panel Type R) To CRS (Q-Panel Type S) To CRS (Q-Panel Type D) To aged industrial alkyd paint Stencil Release (20 mil application) Early Rust 6 No failure No failure No failure No failure 2 to 3 hours after application No blister or rust formation Water Resistance (3.5 to 4 mil DFT) 24 Hour Water Immersion Slight discoloration while wet. Complete recovery after drying. 100 Hours Condensation (40ºC) cabinet exposure Film dulling

8 Page 8 of 14 Footnotes: 1. Unless otherwise stated, film cure was for 7 days at 25ºC/50% relative humidity hours light 60 o C followed by 4 hours 40 o C. 3. Cold rolled steel. 4. Blasted hot rolled steel. 5. Cross-hatch tape test mil wet films 7.5 o C/75% relative humidity for 6 hours followed by 24 hour exposure to water saturated cheese cloth. The excellent corrosion resistance of the 10 PVC gloss yellow coating based on Rhoplex WL- 100 resin is demonstrated in the following photograph. 100 Hours Salt-Spray Exposure on Untreated Cold-Rolled Steel One coat, 2 mil dry film thickness applied direct-to-metal. One week dry at 75ºF/50% relative humidity prior to exposure.

9 Page 9 of PVC WHITE GLOSS PAINT BASED ON RHOPLEX WL-100 RESIN Ingredients Pounds Gallons Grind Water Propylene Glycol Tamol 165A Surfynol 104A Ammonia (28%) Dehydran Ti-Pure R Water Grind Sub-total Letdown Rhoplex WL Propylene Glycol Add grind at this point Premix Dowanol DPnB Water Premix Sub-total Sodium Nitrite (15%) Acrysol RM Premix Acrysol RM Water Premix Sub-total Totals

10 Page 10 of 14 The photos below show the excellent adhesion of the Rhoplex WL-100 based white gloss paint to an alkyd paint compared to a gloss white paint based on a commercially available competitive styrene-acrylic binder. Adhesion to alkyd paint tested ( Tape pull) after 1 week cure, 3.5 DFT. Left based on Rhoplex WL-100. Right based on a competitive styrene acrylic. Adhesion to alkyd paint tested after 1 week cure and exposed to 6 hours water mist. 3.5 DFT. Left based on Rhoplex WL-100 resin. Right based on a competitive styrene acrylic.

11 Page 11 of 14 PROPERTIES 1 OF WHITE GLOSS PAINT BASED ON RHOPLEX WL Total PVC 17% Volume Solids 37.9% Weight Solids Density Viscosity (initial) lb./gal. 80 to 90 KU 10 day heat aged (@ 60ºC) Pass Freeze-Thaw stability Pass 2 cycles VOC (g/l) 229 Film Gloss 2 (3-4 mil DFT) o and o DOI 70 Salt Fog Exposure (ASTM B-117) (4 mil DFT on HRS 3 ) Very few No. 7 blisters along scribe 7 Day exposure Adhesion 4 (DFT 3.5 to 4 mils) to CRS (Q- Panel Type R) No failure before and after 24-hour water soak. Water Resistance 2 (3.5 to 4 mil DFT) 24 Hour Water Immersion No effect 100 Hours Condensation (40 o C) cabinet Film dulling exposure Footnotes: 1. Unless otherwise stated, film cure was for 7 days at 25 C/50% relative humidity. 2. Cold rolled steel. 3. Blasted hot rolled steel. 4. Cross-hatch tape test.

12 Page 12 of PVC REACTIVE PIGMENT CONTAINING PRIMER BASED ON RHOPLEX WL-100 RESIN Ingredient Pounds Gallons Grind Propylene Glycol Water Tamol 165A Ammonia (28%) Triton CF Tego Foamex Red iron oxide (Bayferrox 215M) Atomite Heucophos ZMP Letdown Rhoplex WL Water Ammonia (15%) ph to 9 with ammonia them add grind Dowanol DPnB Dibutyl Phthalate Tego Foamex Sodium Nitrite (15%) Acrysol RM-8W Viscosity to ~70 KU Water Totals Property Total PVC 35% Volume Solids 39.01% Weight Solids 53.82% Density lbs./gal. Initial Viscosity (KU) 73 VOC (g/l) 195 Paint Heat 140 F/10 Days (Delta KU) Paint Heat 140 F/10 Days Sheared +13 OK

13 Page 13 of 14 The excellent corrosion resistance of the reactive pigment containing primer based on Rhoplex WL-100 is show below. One coat, 3.5 mil dry film thickness applied to untreated cold rolled steel. One week dry at 75ºF/50% relative humidity prior to 2 week salt fog exposure. MATERIAL SAFETY DATA SHEETS Rohm and Haas Material Safety Data Sheets (MSDS) contain pertinent information that you may need to protect your employees and customers against any known health or safety hazards associated with our products. Under the OSHA Hazard Communication Standard, workers must have access to and understand MSDS on all hazardous substances to which they are exposed. Thus, it is important that you provide appropriate training and information to your employees and make sure they have available to them MSDS on any hazardous products in their workplace. Rohm and Haas Company sends MSDS for all its products, whether or not they are considered OSHA-hazardous, to both the bill to and/or ship to locations of all its customers upon initial shipment, including samples. If you do not have access to one of these MSDS, please contact your local Rohm and Haas representative for an additional copy. Updated MSDS are sent upon revision to all customers of record. In addition, MSDS are sent annually to all customers receiving products deemed hazardous under the Superfund Amendments and Reauthorization Act. MSDS should be obtained from your suppliers of other materials recommended in this bulletin. Rohm and Haas Company is a member of the American Chemistry Council and is committed to

14 Page 14 of 14 ACC s Responsible Care Program. ACRYSOL, RHOPLEX, and TAMOL are trademarks of Rohm and Haas Company or of its subsidiaries or affiliates and are intended to designate goods marketed in North America; the same goods may be marketed in other countries, generally under other Company trademark designations. These suggestions and data are based on information we believe to be reliable. They are offered in good faith, but without guarantee, as conditions and methods of use of our products are beyond our control. We recommend that the prospective user determine the suitability of our materials and suggestions before adopting them on a commercial scale. Suggestions for uses of our products or the inclusion of descriptive material from patents and the citation of specific patents in this publication should not be understood as recommending the use of our products in violation of any patent or as permission or license to use any patents of the Rohm and Haas Company. Rohm and Haas Company, A461 February 2002 Printed in U.S.A.