DuPont VMX Developmental Product Information October 2013

Transcription

1 DuPont VMX-2122 High Viscosity, Peroxide Cured AEM Dipolymer Developmental Product Information October 2013 VMX-2122 Introduction Vamac ethylene acrylic elastomer, introduced in 1975, has been successfully used for many years in demanding automotive applications, where excellent resistance to heat, engine and transmission fluids or Blow-By is required. DuPont s latest manufacturing technology allows production of enhanced AEM grades that are significantly improved compared to the existing standard Vamac elastomers. These grades, designated and sold as Vamac Ultra, provide a true step-change improvement in processability, performance and customer value for targeted applications. The new manufacturing technology has now also been applied to a new EMA Dipolymer, called VMX Major Performance Properties and Applications Higher viscosity is the major difference between the standard AEM grades and the Vamac Ultra family of polymers, of which four Terpolymers, cured by Diamine curatives, have been already commercialized. VMX-2122 is a high viscosity version of Vamac DP. It provides good mold release, comparable to Vamac Ultra Terpolymers. Increased green strength of compounds helps to avoid collapse during extrusion processes, and may help in applying reinforcement layers without cutting the inner tube by filaments. The optimized polymer structure ensures gains in physical properties, resulting in improved performance of rubber parts such as cables, seals, gaskets or extruded hoses. Best physical properties of VMX-2122 are obtained in rubber parts having a hardness range between 50 and 90 Shore A. Handling Precautions Because VMX-2122 contains small amounts of residual methyl acrylate monomer, adequate ventilation should be provided during storage and processing to prevent worker exposure to methyl acrylate vapor. Additional information may be found in DuPont Material Safety Data Sheet (MSDS), and bulletin, Safe Handling and Processing of Vamac (VME-A10628), available from DuPont Performance Polymers. Like every other grade of Vamac, VMX-2122 is halogen-free. Typical properties of this new experimental polymer are shown in Table 1. Table 1 - Vamac VMX Typical Product Properties Property Limit Method Form Bale size is nominally: 560 mm by 370 mm by 165 mm (22 in. by 15 in. by 7 in.) Visual Inspection Color Clear Visual Inspection Total Volatile Matter < 0.6% DuPont MP Polymer Viscosity ML (1+4), 100 C (MU) 26 ± 8 ASTM D 1646

2 Mixing VMX-2122 has higher viscosity than Vamac DP which permits better and faster dispersion of fillers and other compounding ingredients. VMX-2122 also showed reduced sticking to mixing equipment in all lab tests compared to Vamac DP. Due to the general good scorch safety of peroxide cured compounds, changes in mixing cycle due to higher viscosity are not considered necessary. Compounding and Physical Properties- Wire & Cable Table 2 shows a comparison of VMX-2122 to Vamac DP in identical formulations, which can be used as a starting point for halogen-free, flame retardant Wire & Cable applications. Table 2 - Compound Properties, HFFR W&C Compound Vamac DP 100 VMX Naugard Armeen 18 D Stearic Acid Martinal OL-111 LE Dynasilan Perkadox 14-40B-GR Rubber chem HVA Total PHR Polymer Mooney ML 100 C Compound Mooney ML 100 C MDR 180 C / 0.5deg / 15 min ML (dnm) MH (dnm) Ts 1 (min) Ts 2 (min) t10 (min) t50 (min) t90 (min) Tan at MH Peak rate (dnm/min) Compression Moulding, C Original 23 C Hardness (Sh. A, 1 sec.), 6 mm plied Tensile Strength at Break ISO 37 T2 (MPa) Elongation at Break (%) M 100% (Mpa) Crescent Tear Die C, ISO 34-1 Fmax (N/mm) Trouser Tear Die A, ISO 34-1 Fmax (N/mm) Tg by DSC 10 C/min ( C) Ageing 168 h at 100 C in IRM 903 Hardness (Sh. A, 1 sec.), 6 mm plied Hardness Change (pts.) Tensile Strength at Break (Mpa) Tensile Strength at Break Change (%) 5 3 Elongation at Break % Elongation at Break Change (%) M 100% (Mpa) Volume Change (%) Weight Change (%)

3 Ageing in air 168 h at 160 C Hardness (Sh. A, 1 sec.), 6 mm plied Hardness Change (pts.) 7 4 Tensile Strength at Break (Mpa) Tensile Strength at Break Change (%) 16 7 Elongation at Break % Elongation at Break Change (%) M 100% (Mpa) M 100% Change (%) Ageing in air 168 h at 175 C Hardness (Sh. A, 1 sec.), 6 mm plied Hardness Change (pts.) 6 5 Tensile Strength at Break (Mpa) Tensile Strength at Break Change (%) 10 2 Elongation at Break % Elongation at Break Change (%) M 100% (Mpa) M 100% Change (%) Polymer and Compound Mooney are higher for VMX The tighter crosslink network and faster cure lead to slightly higher Hardness, with higher Tensile Strength and still slightly higher Elongation at Break. The polymer lots used for this study slightly differ in MA content, which can be seen from differences in Tg and Volume Swell in IRM-903. After Heat Ageing, VMX-2122 maintains its properties better than Vamac DP.

4 Compounding and Physical Properties Carbon Black Filled Compounds The major difference between compounds based on diamine cured Vamac Terpolymers and peroxide cured Dipolymers is that process aids and plasticizers have to be kept at a minimum needed for good low temperature performance and good mold release, as they significantly impact the cure speed and crosslink density of peroxide cure systems. However, addition of small amounts of Vanfre VAM showed positive impact on heat ageing in our lab tests. In simple Carbon Black filled compounds shown in Table 3, VMX-2122 showed slightly faster cure, higher MH, along with significant better combination of tensile and Elongation and Break compared to Vamac DP, whilst Compression Set was slightly inferior for VMX Table 3 - Compound Properties, 70 Shore A Carbon Black Filled Compounds Vamac DP 100 VMX Vanfre VAM Naugard Stearic Acid Reagent (95%) Spheron SOA (N 550) Luperox DC 40 P Rubber chem HVA 2 3 Sartomer SR 350 (TRIM) 3 3 Diak No. 7 (TAIC) 3 Mooney Viscosity ML 1+4, 100 C MDR cure rate 15 min. / 180 C, arc 0.5, ISO 6502:1999 ML [dnm] MH [dnm] Ts2 [min] T10 [min] T50 [min] T90 [min] Tan delta at MH Peak rate [dnm/min] Compression moulding 10 minutes at 185 C Hardness Shore A (1 second) Tensile properties (type 2) at 23 C Tensile Strength [MPa] Elongation at break [%] Modulus at 100 % [MPa] Cset 70 h / 150 C, pliediso 815-1:2008 (%) Cset o-ring (ASTM D 1414) 70 h / 150 C - size: AS-214 ASTM D min/185 C comp. molded o-ring (%) Cset o-ring (ASTM D 1414) 70 h / 150 C - size: AS-214 ASTM D min/185 C comp. molded o-ring (%) Cset, VW 22 h/150 C VW PV 3307 [%] Cset, 168 h/ 150 C plied, ISO [%] Tensile properties (type 2) at 150 C ISO 37 Tensile Strength [MPa] Elongation at break [%] Modulus at 100 % [MPa] Replacing TRIM as coagent by TAIC or HVA-2 results in much higher MH and better Compression Set, but properties measured at room temperature and 150 C are low, which may result in problems during moulding or in the final application.

5 Optimization of Properties and Compression Set To obtain a good combination of Compression Set resistance and physical properties, Table 4 shows possibilities with combinations of coagents and an alternative peroxide with higher decomposition temperature. Table 4 Optimizing Compression Set and Physical Properties Coagent Level and Type VMX Naugard Stearic acid Vanfre VAM Spheron SOA N Rubber chem HVA Sartomer SR 350 (TRIM) 1.5 Diak No. 7 (TAIC) Luperox 101 XL 45 8 Luperox DC 40 P MDR cure rate 15 min at 180 C, arc 0.5 ML [dnm] MH [dnm] Ts1 [min] Ts2 [min] T10 [min] T50 [min] T90 [min] Tan delta at MH Peak rate [dnm/min] Compression moulding 5 min. / 185 C Hardness Shore A (1 second) Tensile properties (type 2) at 23 C Tensile Strength [MPa] Elongation at break [%] Modulus at 100 % [MPa] Comp set 70 h / 150 C - plied (%) Compression moulding 10 min. / 185 C Hardness Shore A (1 second) Tensile properties (type 2) at 23 C Tensile Strength [MPa] Elongation at break [%] Modulus at 100 % [MPa] Compression set 70 h / 150 C plied (%) A combination of TAIC with either HVA-2 or TRIM offers good combinations of physical properties and Compression Set, as well as options for reduced cure times. Dicumylperoxide provided better Compression Set, but results have to be taken with care, as active oxygen index at same phr levels are different for both peroxides used.

6 Another study, shown in Table 5, looked at different peroxide levels to those typically used for Vamac DP. Table 5 Optimizing Compression Set and Physical Properties Peroxide Level Vamac DP 100 Vamac VCX Naugard Stearic Acid Reagent (95%) Vanfre VAM Spheron SOA (N 550) Sartomer SR350 (TRIM) Luperox DC 40 P Rubber chem Diak no Luperox 230 XL 40 SP 2.5 Mooney Viscosity ML 1+4, 100 C [MU] MDR, 15 min at 180 C, arc 0.5 ML [dnm] MH [dnm] Ts1 [min] T10 [min] T50 [min] T90 [min] Tan delta at MH Peak rate [dnm/min] Compression moulding 5 min at 185 C Hardness Shore A (1 second) Tensile Strength [MPa] Elongation at break [%] Modulus at 100 % [MPa] Compression set 70 h / 150 C, plied disks, 3x2 mm ISO 815-1: VMX-2122 provided best Compression Set resistance at levels of about 6.5 phr Dicumylperoxide. This level also provides significant better Elongation at Break.

7 O-rings, manually demoulded Injection Moulding Performance Vamac Terpolymers are usually material of choice for parts that are produced in Injection, Transfer or Compression Moulding. Dipolymers historically have been chosen rarely due to stickiness of peroxide cured AEM compounds. VMX-2122 showed excellent properties in demoulding in lab trials, reaching performance levels of Ultra Terpolymers like Vamac Ultra IP. The procedure used in DuPont labs to determine mold release uses a horizontal injection moulding machine, and a mold with 40 cavities of O-rings, Size AS-214. Cold runners are used, and central single point injection. The mold is cleaned according to the same procedure before a new compound is tested. Mold temperature has been set at 185 C. Cure time has been set at 30 seconds, where blister-free O-rings have been obtained. After mold opening, a brush is removing most of the O-rings from the mold. The number of O-rings sticking to the mold after brushing is counted. Vamac DP 100 Table 6 Compounds used for Injection Moulding Tests VMX-2122, Vamac DP VMX-2122 TRIM VMX-2122, VMX-2122, Process Aid Process Aid VMX-2122, in compound in polymer Plasticizer VMX VMX Naugard Stearic Acid Reagent (95%) Vanfre VAM Spheron SOA (N 550) Alcanplast PO Rubber chem HVA Sartomer SR 350 (TRIM) 3 Luperox DC 40 P Chart 1 shows the protocol of the IM trials, reporting the number of O-rings that had to be removed from the mold manually throughout the 50 shots that have been made with each of the compounds shown in Table 5. Whilst the compound based on Vamac DP (green line) could not be well demolded, nearly all the O-rings based on VMX-2122 were released either automatically or by brushing. Chart 1 Injection Moulding Test Report, O-rings, Manually Demolded Vamac DP VMX-2122 VVMX-2122VMX

8 Fluid Resistance, Comparison to AEM Terpolymers Vamac Terpolymers are known for their excellent sealing capabilities and extensively used for seals such as cam cover gaskets, oil pan gaskets or transmission seals in harsh automotive environments. New oils contain significant levels of additives, which lead to additional crosslinking effects of AEM Terpolymers during ageing in such oils. VMX-2122 as a Dipolymer does show much less tendency to form such crosslinks during fluid ageing and maintains its original Elongation at Break levels much better, as shown in Table 7. Exxon MB Formula 5W30 is used as first fill oil for truck diesel engines, Fuchs Titan 5W30 as a first fill oil for passenger car gasoline engines by a well-known German OEM. Pentosin FFL-4 is a lubricant used in automatic transmissions. Table 7 Comparison to Vamac Terpolymers, Engine Oil Ageing Vamac GLS 100 Vamac Ultra LS (VMX-3110) 100 Vamac Ultra IP (VMX-3040) 100 VMX Naugard Vanfre VAM Armeen 18D PRILLS Stearic Acid Reagent (95%) MT Thermax Floform N Spheron SOA (N 550) 25 Regal SRF N Alcanplast 810 TM Rubber chem Diak no Alcanpoudre DBU Luperox DC 40 P 8 Rubber chem HVA 2 2 Press-Cure, 5 min / 190 C, Post-cure 4 h / 175 C Hardness Shore A (1 sec) Tensile Strength [MPa] Elongation at break [%] Modulus at 100 % [MPa] C.Set, 24 h / 150 C, plied, ISO815-1:2008 [%] C.Set, 94 h / 150 C, VW PV3307: [%] C.Set, 22 h / 150 C, plied, ISO 815-B (cold release) Fluid ageing 1008 h / 150 C in Exxon Mobil MB Formula , 5W-30, Hardness Shore A (1 sec) Delta hardness Tensile Strength [MPa]

9 Delta TS [%] Elongation at break [%] Delta Elong. [%] Modulus at 100 % [MPa] Delta 100% [%] Weight Change [%] ISO 1817: Volume Change [%] ISO 1817: Fluid ageing 1008 h / 150 C in Fuchs Titan EM (HTHS 3,5), 5W-30 Hardness Shore A (1 sec) Delta hardness Tensile Strength [MPa] Delta TS [%] Elongation at break [%] Delta Elong. [%] Modulus at 100 % [MPa] Delta 100% [%] Weight Change [%] ISO 1817: Volume Change [%] ISO 1817: Fluid ageing 1008 h / 150 C in Pentosin FFL-4 Hardness Shore A (1 sec) Delta hardness Tensile Strength [MPa] Delta TS [%] Elongation at break [%] Delta Elong. [%] Modulus at 100 % [MPa] Delta 100% [%] Weight Change [%] ISO 1817: Volume Change [%] ISO 1817: Continuous Vulcanization without external Pressure (UHF, Salt Bath) Vamac Terpolymers are used as standard material for hoses, due to good physical properties and excellent green strength of compounds for extrusion. Dipolymer compounds usually had lower green strength. VMX-2122 offers higher green strength and better properties compared to Vamac DP and can meet existing AEM specifications. Straight tubes can be cured in pressureless, continuous systems like UHF ovens or salt baths. Suitable compounds need Calcium Oxide (CaO) as absorbent for moisture which is always present in any rubber compounds. CaO would react with the acidic cure sites of Vamac Terpolymers, for which reason these polymers cannot be used for such cost-effective continuous vulcanization processes. Vamac Dipolymers can be used along with CaO, and some compounding possibilities have been developed in the past to produce compounds fit for use in pressureless cure processes. VMX-2122 showed improvements over Vamac DP in lab trials, which did not use all tricks. For example, a combination of two peroxides with lower and higher decomposition temperatures was not used in this study. Table 8 gives some indications, more Info can be provided on request.

10 Table 8 Compounds for Pressureless Cure Processes Vamac DP Vamac Ultra LS (formerly VMX-3110) VMX Naugard Armeen 18D PRILLS Stearic Acid Reagent (95%) Struktol WS Kezadol GR Spheron SOA (N 550) MT Thermax Floform N Luperox DC 40 P Sartomer SR350 (TRIM) Mooney Viscosity ML 1+4, 100 C, MU MDR, 12 min / 190 C, arc 0.5 ML [dnm] MH [dnm] Ts1 [min] T50 [min] T90 [min] Tan delta at MH Peak rate [dnm/min] Compression Moulding, 5 min / 190 C Hardness Shore A (1 second) Tensile Strength [MPa] Elongation at break [%] Modulus at 100 % [MPa] Trouser Tear, Type A, ISO 34-1, N/mm C.set 70 h / 150 C - Type B, ISO (%) C.set 70 h/ 150 C Plied, ISO (%) Ageing 168 h/150 C in Lubrizol OS Hardness Shore A (1 second) Delta hardness Tensile Strength [MPa] Delta TS [%] Elongation at break [%] Delta Elong. [%] Modulus at 100 % [MPa] Delta 100% [%] Weight Change (%) Volume change [%] These compounds were extruded through a Garvey Die and then cured in a standard heat ageing oven. Compound 1 and 3 showed significant blistering, VMX-2122 being significantly better. The blends with 15 phr of Ultra LS were significantly lower in blistering, 25 phr of Ultra LS along with VMX-2122 was principally free of blisters.

11 List of Compound Ingredients Material Chemical Composition Supplier Polymer Vamac GLS Ethylene Acrylic Elastomer DuPont Performance Polymers Vamac Ultra LS Ethylene Acrylic Elastomer DuPont Performance Polymers Vamac Ultra IP Ethylene Acrylic Elastomer DuPont Performance Polymers Vamac DP Ethylene Acrylic Elastomer DuPont Performance Polymers VMX-2122 Ethylene Acrylic Elastomer DuPont Performance Polymers Release Aids Armeen 18D Octadecyl Amine Akzo Nobel Vanfre VAM Complex Organic Phosphate Ester R.T. Vanderbilt Stearic Acid Anti-Oxidant Naugard 445 Diphenyl Amine Chemtura Plasticizer Alcanplast 810TM Trimellitate Plasticizer Safic-Alcan Alcanplast PO80 Mixed Ether/Ester Plasticizer Safic-Alcan Fillers Spheron SOA (N 550) Carbon Black Cabot Regal SRF N 772 Carbon Black Cabot MT Thermax Floform N 990 Carbon Black Cancarb Martinal OL-111 LE Al(OH) 3 Martinswerke Dynasilan 6490 Coupling Agent Evonik Curatives Diak TM No. 1 Hexamethylene Diamine Carbamate DuPont Performance Polymers Perkadox 14-40B-GR Di(tert-butylperoxyisopropyl)benzene AkzoNobel Luperox DC 40 P Dicumylperoxide Arkema Accelerators Alcanpoudre DBU-70 DBU accelerator Safic-Alcan Rubber chem HVA-2 N,N'-phenylene bismaleimide DuPont Performance Polymers Sartomer SR 350 Trimethylolpropane Trimethacrylate Arkema Diak No. 7 Triallylisocyanurate DuPont Performance Polymers Test Fluids IRM-903 Reference Fluid Pentosin FFL-4 Transmission Fluid Deutsche Pentosinwerke Fuchs Titan EM W30 Engine Oil Fuchs Mobil MB Formula 5W30 Engine Oil Exxon Mobil

12 Test Methods Test Method Rheology Mooney Viscosity ISO 289-1:2005 Mooney Scorch ISO 289-2:1994 MDR ISO 6502:1999 Physical Properties Hardness ISO 868:2003 Tensile Strength, Elongation, Modulus ISO 37:1994 Compression Set ISO 815:1991 Compression Set Volkswagen PV3307 Compressive Stress Relaxation (CSR) ISO 3384 Aging in Air Oven ISO 188:2007 Fluid Aging ISO 1817:2005 Tg by DSC ISO 22768:2006 Tear Strength Die C ISO 34-1:2004

13 Visit us at Vamac.dupont.com Contact DuPont at the following regional locations: North America Greater China Latin America ASEAN Europe, Middle East, Africa Japan The information set forth herein is furnished free of charge and is based on technical data that DuPont believes to be reliable and falls within the normal range of properties. It is intended for use by persons having technical skill, at their own discretion and risk. This data should not be used to establish specification limits nor used alone as the basis of design. Handling precaution information is given with the understanding that those using it will satisfy themselves that their particular conditions of use present no health or safety hazards. Since conditions of product use and disposal are outside our control, we make no warranties, express or implied, and assume no liability in connection with any use of this information. As with any product, evaluation under end-use conditions prior to specification is essential. Nothing herein is to be taken as a license to operate or a recommendation to infringe on patents. Caution: Do not use in medical applications involving permanent implantation in the human body. For other medical applications, discuss with your DuPont customer service representative and read Medical Caution Statement H Copyright 2012 DuPont. The DuPont Oval Logo, DuPont, The miracles of science, Vamac and Diak are trademarks or registered trademarks of E.I. du Pont de Nemours and Company or its affiliates. All rights reserved. Vulcofac is a registered trademark of Safic-Alcan Dexron is a registered trademark of General Motors Castrol is a registered trademark of Castrol Spheron and Regal are registered tradmarks of Cabot Corporation. Thermax is a registered trademark of Cancarb. Naugard is a registered trademark of Uniroyal. Armeen is a registered trademark of Akzo Nobel. Vanfre is a registered trademark of R.T. Vanderbilt. Edenol is a registered trademark of Cognis Oleochemicals. Lubrizol is a registered trademark of Lubrizol Corporation. Vulcofac, Nycoflex, ALcanpoudre are registered trademarks of Safic-Alcan. Rhenosin is a registered trademark of Rhein-Chemie. Ekaland is a registered trademark of MLPC International. (07/12) Reference No. VME-A A1113