New Amine Curatives for Polyurea Coatings and Caulkings Paul Wiggins, Judith Orgad and John Lee In this presentation I will share with the work that we have been doing in the lab in developing new amine curatives and testing them in polyurea systems. Albemarle Corporation Process Development Center Gulf States Road Baton Rouge, LA 70805 (225)359-2017 Polyurethanes 2005 Technical Conference and Trade Fair October 17-19, 2005

Curative Growth Opportunities Hot Cast Polyurethane Good Dynamic Properties Optically Clear Elastomers Coatings Polyurea Spray Coatings Polyurethane Coatings Room Temperature Cast Polyurethane Tire fill RIM Run Flat Tire Here I will share we you the opportunities that have lead us to develop new curatives. In hot cast polyurethane, Ethacure 100 can be used to make small wheels or castors but it is too fast to make larger wheels. Ethacure 300 has the correct cure profile for larger wheels but does not have the dynamic properties. There is an opportunity for a slower curative with good dynamic properties. Presently small optically clear elastomers can be made as shown here in this gas mask but the system is too fast to make larger castings. There is a need for a slower curative that will provide an optical clear elastomer. In the coatings area Ethacure 100 is used in polyurea spray coating but its speed makes it difficult to process when it is the sole curative so a slower curative would be welcomed by the formulators. Ethacure 300 has seen limited use in polyurethane coatings because of poor UV resistance so a slower curative would good UV resistance is needed. In room temperature cast the use of amine curative are limited in tire fill because they are too fast and a slower curative would allow more to be incorporated into the formulation and provide better properties. In RIM applications such as the run flat tire, a slower curative would allow the designer of the parts more latitude in designing more complex parts.

Goal To provide cure speed flexibility in selecting amine curing agents for polyurea and polyurethane applications. To test rapidly. To compare against standard Ethacure® 100 base formulations.

Baseline Formulation The formulation below is a standard polyurea system containing Albemarle’s Ethacure® 100 curative. We will evaluate other curatives and curative blends against the properties obtained from this standard formulation. Side A Component Rubinate® 9480 MDI, 14.9 % NCO Side B Components Jeffamine® D-2000 polyether amine 66.1 Jeffamine® T-5000 polyether amine 5.8 Ethacure® 100 aromatic diamine 28.1

Processing A MIXPAC DP-400-85-1 pneumatic dispensing gun was used with the static mixers listed below: The polyurea was extruded onto a steel plate and cured at room temperature for 2 weeks before physical property measurement. Elements I.D. EA 370-30 30 0.37” MS 06-48 48 0.25”

Processing

Processing

Processing

Processing

Processing

Baseline Formulation Using Ethacure® 100 Curative The Ethacure® 100 polyurea system is fast. In a static mixer the viscosity increases rapidly making it a challenge to get adequate mixing. Conditions were varied in order to improve the mixing and provide good physical properties.

Mixing Conditions and Gel Times The effects of heating the A-side and B-side were tested. At higher temperatures the viscosity was reduced making the residence time in the static mixer shorter but also shortening the gel time. The most consistent results were obtained when the A-side and B-side were heated.

Physical Properties Temperature 25°C 50°C 66°C 67°C Static mixer, units 30 48 Gel Time, sec 7 <2 Shore D hard., (0sec/10sec) 46/42 45/42 44/41 45/40 Tensile Str., psi 2100 2050 2250 2310 Elongation, % 330 350 320 370 Modulus (100%) 1300 1280 1360 Modulus (300%) 2040 2170 2030 Tear strength, pli 450 430 460

Key Market Needs – New Curatives Cure speed versatility – curatives to meet needs of variety of end-user applications Good properties – clarity, UV, strength Low cost is critical in most applications Good H&E product characteristics are needed for customer acceptance of new materials In Conclusion New materials are costly to introduce (H&E testing, etc.) – need good opportunities

Characteristics of Amine Curing Agents Aromatics Aliphatics Color - + UV Resistance Physical Properties Cost

Slower Reacting Curatives Four new developmental curatives called XP-A, XP-B, XP-C and XP-D were evaluated. XP-A, XP-B and XP-C are aromatic amines, while XP-D is an aliphatic amine. Data on the performance of the commercially available Ethacure® 300 curative is also presented. The Jeffamine® 2000 level in the standard formulation was adjusted to keep the volume ratio of the A-side to B-side at 1:1.

Physical Properties Gel times of the polyurea formulations with the new curatives were longer than those with E-100 (Ethacure 100) while the tensile values were lower than those of E-100 system. Curative E-100 XP-A XP-B XP-C XP-D E-300 Gel Time, sec <2 61 33 97 42 Shore D Hardness(0sec/10sec) 45/40 28/23 31/27 38/34 44/38 43/40 Tensile Strength, psi 2310 1060 1770 1960 2030 1530 Elongation, % 370 470 350 280 Modulus (100%) 1300 520 970 1045 990 1250 Modulus (300%) 800 1620 2070 1720 -- Tear strength, pli 460 240 320 300 440

Gel Time

Physical Properties

Physical Properties of Blends E-100 was blended in a 1:1 weight ratio with the other curative in a polyurea formulation. A balance of physical properties and gel time was obtained. XP-D gave the highest properties. Curative E-100 XP-A XP-B XP-C XP-D Gel Time, sec <2 11 12 10 14 Shore D Hardness(0sec/10sec) 45/40 36/33 36/34 45/41 Tensile Strength, psi 2310 1740 2160 2530 2670 Elongation, % 370 330 290 340 390 Modulus (100%) 1300 1080 1310 1360 Modulus (300%) 2030 1650 2170 2280 2350 Tear strength, pli 460 400 520

Gel Time (sec)

Physical Properties

XP-D It should be noted that XP-D is an aliphatic diamine and is a water white liquid. It has a longer gel time than Ethacure 100. It can be blended with the low color Ethacure 100-LC to produce a system with long gel times and good physical properties for optical clear parts.

Evaluation in Other MDI Systems Rubinate 9480 is a lower viscosity, slower reacting MDI suited for fast reacting Ethacure 100. It has a high level of 2,4’-isomer. It was used in all our formulations so far. Rubinate 9009 which has a low 2,4’-isomer content and a high 4,4’isomer content was evaluated with the slower reacting curatives. It was too fast for E-100 in the static mixer.

Physical Properties Higher tensile strengths were obtained with Rubinate 9009. Formulation E-300 /9480 /9009 XP-A 9009 Gel Time, sec 42 31 53 17 Physical Properties Shore D hardness, (0sec/10sec) 43/40 59/52 29/20 50/44 Tensile Str., psi 1530 2430 920 2280 Elongation, % 280 170 420 130 Modulus (100%) 1250 2140 518 2080 Modulus (300%) -- 770 Tear strength, pli 440 540 250

Conclusions New experimental slower curing agents/blends have been developed to provide a slower curing system than the standard system containing only Ethacure 100 curative. An aliphatic amine curative has been found that is slow enough to be used with an MDI prepolymer providing a slower gel time than Ethacure 100. Rubinate 9009 formulations provided higher tensile strengths than the Rubinate 9480 for the slower curatives.

Conclusions (cont.) Work is continuing with our patent pending process to produce other curatives to optimize cure rate and physical properties. New amine curatives, both aromatic and aliphatic, have been developed within Albemarle. We are awaiting guidance from our H&E group as to the length and cost of testing these new materials prior to starting a sampling program.