1. Cancarb
April 15, 2017

2. Thermax® Thermal Carbon Black Thermax® vs. Furnace Black
Overview
Thermax® Thermal Carbon Black
Thermax® vs. Furnace Black
The Thermax Advantage
Natural Rubber
Nitrile Rubbers
Hydrogenated Nitrile
Polychloroprene
Fluoroelastomers
NBR/PVC Blends
Ethylene Propylene Rubbers
Chlorosulfonated Polyethylene Rubbers – CSM
Butyl and Halobutyl Rubbers
Questions & Answers
Cancarb
April 15, 2017

3. Thermax®
Carbon black can be broadly defined as very fine particle aggregates of carbon, possessing an amorphous quasi-graphitic molecular structure
The most significant areas of distinction between thermal black and furnace black are particle size and structure
Thermax®, thermal carbon black, due to its higher particle size (280 nm) and lower structure, compared to even the most coarse furnace black, can be translated into excellent rubber compound properties
Cancarb
April 15, 2017

4. Thermax® vs. Furnace Black Grades
Particle Size Diameter
How many particles in a gram?
Write down the number 50, now add 12 zeros to that number.
N110
(15nm)
N762
(80nm)
N990
(280nm)
Cancarb
April 15, 2017

5. Thermax® vs. Furnace Black Grades
Low Structure Moderate Structure High Structure
Higher structure blacks, when mixed into rubber compounds will yield a harder, less pliable finished product while lower structure blacks will yield a softer, more pliable finished product.
Chain like
Grape like clusters
Loosely agglomerated
N N N550
Cancarb
April 15, 2017

6. The Carbon Black Spectrum
INCREASING STRUCTURE
OAN (DBP) ABSORPTION (ml/100g)
NITROGEN SURFACE AREA (m2/g)
DECREASING PARTICLE SIZE
Cancarb
April 15, 2017

7. Influence of Carbon Black on Properties
Rubber Property
As Particle size Increases
As Structure Decreases
Mixing temp.
Dispersion
Viscosity
Green Strength
Extrusion Quality
Scorch Safety
Cancarb
April 15, 2017

8. Influence of Carbon Black on Properties
Rubber Property
As Particle size Increases
As Structure Decreases
Tensile
Elongation
Hardness
Tear resistance
Compression set
Heat build up
Abrasion resistance
Resilience
Cancarb
April 15, 2017

9. The Thermax® Advantage
The properties of Thermax® can be translated into rubber compounds with:
Lower heat build-up, especially during extrusion, which is very important for halogen bearing rubbers and high hardness compounds
Low hysteresis loss in dynamic applications, for example; automotive engine mounts
Reduced volume swell in aggressive fluids
Reduced cost
Low compound viscosity which is essential for injection molded and sponge compounds
Cancarb
April 15, 2017

10. Natural Rubber Structure
Natural Rubber (NR)
Natural Rubber Structure
CH3
Natural rubber is polyisoprene
There are four possible isomers of natural rubber
 – CH2 – C = CH – CH2 –
cis–1,4 Isomer
1,4 structure means that ‘C’ atoms 1 and 4 are joined in forming the chain
In the cis-1,4 structure both carbon atoms 1,4 forming the chain are on the same side of the double bond
-CH CH2-
CH H
C=C
Cancarb
April 15, 2017

11. Natural Rubber (NR)
Natural Rubber has outstanding mechanical properties and fatigue resistance making it a very popular choice in dynamic applications
Natural rubber consists of polymer chains all having almost 100% perfect cis–1,4 structure. The true chemical name for this polymer is in fact, cis-1,4-polyisoprene
When the units in a macromolecule all consist of the same molecule, the polymer is said to be stereo regular
Cancarb
April 15, 2017

12. Properties of Natural Rubber (NR)
Crystallizes on stretching, resulting in:
high gum tensile strength
high tensile break
very high tear strength & hot tear resistance
excellent De Mattia cut growth resistance
Gives a glass transition temp (Tg) of approximately -75°C
Has high resilience
Has excellent tack & green strength properties
Imparts low damping (hysteresis) and low heat build-up in dynamic deformation
Is unsaturated (double bonds), resulting in poor resistance to:
Heat aging
Ozone
Oils and hydrocarbons
Cancarb
April 15, 2017

13. Applications of Natural Rubber
Common Applications of Natural Rubber are:
Truck tire tread (Tear, hot tear, low heat build-up)
Passenger radial (Flexibility, low heat build-up)
Anti-vibration (Dynamic deformation)
Conveyor belting (High mechanical properties, tear)
Adhesive tapes and solutions (Tack)
Cancarb
April 15, 2017

14. The Thermax® Advantage in Natural Rubber Compounds
Thermax® maintains the inherent good dynamic properties of the natural rubber polymer
The best choice for anti-vibration applications
Thermax® lowers compound hardness while retaining the good tack properties inherent to natural rubber
Excellent for cushion gum compounds
In wiper blade applications, higher loadings of Thermax® lower the rubber content of the compound which is essential for low noise and a good surface finish.
Cancarb
April 15, 2017

15. NR Compound Example Using Thermax®
Natural Rubber Engine Mount
SMR
Zinc Oxide
Stearic acid
A.O. TMQ N
Thermax N
Aromatic Oil 15 15
CBS 3 3
TMTD
Sulfur
Cure 160°C ‘ ‘
Hardness
Tensile strength
Break %
Dynamic testing at 20 Hz
Tan Delta at 25°C
Cancarb
April 15, 2017

16. ( ) + Nitrile Rubber (NBR) Nitrile Structure butadiene acrylonitrile
- CH2 - CH = CH - CH2 -
- CH2 - CH - CN
Polymer Unit ( )
- (CH2 - CH = CH - CH2)n - CN
CH2 - CH m -
Cancarb
April 15, 2017

17. Nitrile Rubber (NBR)
Nitrile rubbers are high molecular weight copolymers of 1,3-butadiene and acrylonitrile
The percentage of acrylonitrile content can be varied from 18% to 50%, and will influence the performance characteristics of the polymer
The great variation in acrylonitrile content possible with nitrile rubber, allows for compounds to be customized to highlight specific required properties
Cancarb
April 15, 2017

18. Nitrile Rubber – Effect of Acrylonitrile Content
Heat – aging resistance
Abrasion resistance
Tensile
Stiffness
Thermoplasticity
Compatibility with polar polymers
Oil/fuel resistance
Cure rate – Sulphur Cure System
Processability
Density
Increases
As ACN Increases
Air/gas permeability
Low temperature flexibility
Cure rate – peroxide system
Resilience
Decreases
Cancarb
April 15, 2017

19. Nitrile Rubber – Effect of Mooney
Modulus
Green strength
Mill shrinkage
Sheet formation time on mill
Mixing temp
Acceptance of fillers/plasticizers
Incorporation time of fillers
Increases
As Mooney Increases
Decreases
Compression set
Porosity
Cancarb
April 15, 2017

20. Properties of Nitrile Rubbers
Has very good oil and fuel resistance
Can perform over a wide temperature range
Has inherently good resistance to gas permeation which increases as the level of acrylonitrile increases
Can be blended, up to 50%, with polyvinyl chloride (PVC) to produce compounds that exhibit good weathering characteristics in addition to good dynamic properties
Can be co-polymerized with methacrylic or acrylic acid to produce carboxylated nitrile (XNBR), which is noted for its excellent dynamic properties and abrasion resistance
Cancarb
April 15, 2017

21. Applications of Nitrile (NBR)
Common Applications of Nitrile Rubber are:
Gaskets and seals – NBR, XNBR (for high hardness)
Hoses – NBR (mainly in tubes), NBR/PVC (mainly in covers)
Belting – NBR
Rollers – NBR, XNBR (for high hardness)
Cable Jackets – NBR/PVC
Textile (spinning cots/aprons) – NBR, NBR/PVC, XNBR
Industrial footwear – NBR, NBR/XNBR blend, NBR/PVC sponge
Insulation – NBR/PVC sponge
Molded/extruded components for various industries & automotive
Fabric proofing – NBR
Milking inflation - NBR
Cancarb
April 15, 2017
Fabric proofing – Protective coatings (NBR)

22. The Thermax® Advantage in NBR Compound Applications
Higher loadings are achievable with Thermax®, which reduces the rubber content enabling for lower swell in aggressive fluids
Gaskets and seals
Thermax® promotes good extrusion properties and low heat development, avoiding potential scorch problems. This is critical for high hardness compounds
Hydraulic hose tubing
Thermax® maintains the desired hardness of a compound while lowering the viscosity for effective blowing
NBR/PVC Sponge Insulation, hoses and soles
Cancarb
April 15, 2017

23. > > Nitrile Compound Example Using Thermax®
Hydraulic Hose (Broad Temperature Range)
Nitrile Rubber 100 (33-34% ACN, Mooney)
ZnO 5
St. acid 1
Processing Additive 2
A.O. Aminox (DPA + Acetone reaction product)
A.O. ZMBI (Zn Salt of 2 – Mercaptobenzimidazole)
N Suitable blend for good processing,
N vulcanizate properties and good heat ageing
Paraplex G-25 10 KP
Sulfasan R 1
CBS 3
TMTD 3
166° 15'
SH / TS / EB 70 / 152 / 270
Vol. swell % 19 (ASTM Oil 3 / 70h 135°C)
Blending with Thermax N990 helps improve scorch safety during extrusion due to lower heat development. Higher filler loading improves over all extrusion properties and sealing with end couplings
>
>
Blend of polyester and phosphate plasticizers for resistance to heat extraction and low temperature cracking 23
Cancarb
April 15, 2017 23

24. Hydrogenated NBR (HNBR)
Hydrogenated nitrile rubber is based on NBR that has been chemically altered (hydrogenated), resulting in a much lower amount of unsaturation in the polymer backbone. HNBR exhibits significantly improved heat resistance, compared to NBR, while retaining excellent oil and fuel resistance.
HNBR Range
% Hydrogenation % ACN content Mooney (ML 100°C)
~ 85 to to to 150 24
Cancarb
April 15, 2017 24

25. Comparison with NBR for 50 phr FEF compound-Peroxide cured
HNBR+ 50 phr FEF
NBR+ 50 phr FEF
99+ % hydrogenation
38% ACN
38% ACN
55* Mooney
50** Mooney
Mooney (ML 100°C)
Hardness (Shore A)
T.S. (M.Pa)
EB (%)
Tear Die C (KN/m)
Comp. Set % (168h/150°C)
Abrasion (DIN mm3 loss)
Air Ageing (168h/150°C)
Hardness
T.S. (%) Nil Brittle
EB (%) Brittle
The significant improvements in the properties of HNBR over NBR, especially in compression set & heat ageing, bring HNBR very close to specialty rubbers.
*ML
**ML 25
Cancarb
April 15, 2017 25

26. Hydrogenated NBR (HNBR)
HNBR* ACM FKM VMQ  
Tensile
Heat Resistance
Comp. Set
Low Temp
Gear Oil
ASTM Oil #
Sour Gasoline
Rating:1 Best; 7 Worst
*99+ % Hydrogenation 26
Cancarb
April 15, 2017 26

27. Timing belts (automotive) – ozone resistance, flexing
Applications of HNBR
Timing belts (automotive) – ozone resistance, flexing
Power steering rotary shaft seals
‘O’ rings
Oil well specialties
Rollers
Air conditioning hoses for cars
Cancarb
April 15, 2017

28. The Thermax® Advantage in HNBR Compounds Applications
HNBR rubbers have inherently good mechanical properties and do not require a reinforcing black. Thermax® maintains the good mechanical properties of HNBR while lowering the compound viscosity which is essential for easy processing
Thermax® does not degrade the excellent compression set of the HNBR polymer
Higher loadings are possible with Thermax® resulting in lower polymer content which provides lower oil swell and a significant reduction in the overall compound cost
Thermax® allows for extrusion with lower heat build-up giving better scorch safety and further improved impermeability of HNBR
Cancarb
April 15, 2017

29. HNBR Compound Example Using Thermax® Low Compression Set HNBR Seal
Low Compression Set Seal
TORNAC A (99.5% saturation) 100
Thermax® N990 50
Plasticizer WB 300* 5
ZnO 5
Stearic acid 1
Trigonox ** 8
TAIC 3
ML 100°C 70
MS Mooney Scorch at 125°C >25 ‘
Cure time at 180°C 9’
SH/TS/EB 60/146/235
Air aging 150°C / 168H +8/-3/-40%
Compression Set 70 h / 150°C 12
Thermax® maintains good low compression viscosity/mold flow, allows for less polymer content, low swell, adequate tensile strength and excellent compression set
*Mixture of Aliphatic / Aromatic polyesters
** 2,5 dimethyl – 2,5 bis (tert butyl peroxy) hexane (Akzo). 29
Cancarb
April 15, 2017

30. NBR/PVC Blends
Both NBR and PVC are polar which makes them very compatible, typically a 70/30 ratio
NBR provides resistance to heat and organic fluids but has poor resistance to weathering and ozone due to unsaturation.
PVC provides resistance to weathering, ozone and aliphatic hydrocarbons oils
PVC also improves processing, reduced flammability and mechanical properties such as T.S., tears and abrasions 30
Cancarb
April 15, 2017

31. Carboxylated NBR (XNBR)
Carboxylated NBR (XNBR) is a terpolymer NBR with acidic organic monomer (typically 1 & 7%) carboxylic acid as a third monomer
Reactions of ZnO and Carboxylic Acid result in a matrix with significantly increased mechanical properties, such as higher hardness, abrasion resistance and tear strength
Although sacrifice in processing (mill and mould sticking) scorch, resilience and low temperature resistance, product retains the basic properties of NBR (oil & fuel resistance) 31
Cancarb
April 15, 2017

32. Applications
Gasket and Seals - mainly NBR, high hardness seals ex/ Mud Pump – XNBR
Hoses – NBR mainly in tubes, NBR/PVC bend mainly in cover
Beltings
Rollers – NBR, XNBR for higher hardness rollers
Cable Jackets – NBR/PVC blends
Textile – spinning cots/aprons, NBR, NBR/PVC, XNBR
Industrial Footwear – NBR, NBR/XNBR blend, NBR/PVC sponge soiling
Insulation – NBR/PVC sponge
Moulded/extruded components for various industries, automotive
Fabric proofing – protective coatings, NBR
Milking inflation – NBR, resistance to fat 32
Cancarb
April 15, 2017

33. NBR/PVC Blend Example Using Thermax®
Gasohol Resistant Hoses
Compound 1
Compound 2
NBR/PVC Blend70/
Sulphur
ZnO
St. acid N
Thermax® N
DOP
A.O. ODPA
P. Wax
TMTM
ML, 100°C
MS, 23’ 22’
Cure 160°C ’ 7.5’
SH/TS/EB /143/ /131/415
Comp. set 22 h/70°C
Ageing in M15 test fuel (FAM 85 – Methanol 15), 48h at 23°C
Change /-59/-60/+47.8v /-27/-51/+39v
High loading of Thermax® lowers the polymer content allowing for low swell in aggressive fuels, low compression set and good extrusion. 33
Cancarb
April 15, 2017

34. Polychloroprene Structure
Polychloroprene (CR)
Polychloroprene Structure
2-chlorobutadiene
trans-1,4 polychloroprene (88-92 %)
-CH H
CH2 = C – CH = CH2
C=C Cl
Cl CH2-
Chloroprene (liquid)
Similar to trans-1,4 isoprene but, the
‘CH3’ group has been replaced by ‘Cl’
Cancarb
April 15, 2017

35. Polychloroprene (CR)
Polychloroprene is often called neoprene. Neoprene is, in fact, the trade name of Dupont Dow Elastomers polychloroprene product line
Polychloroprene has a structure similar to that of natural rubber except one of the methyl side groups is replaced by a chlorine atom and it is a trans-oriented molecule
Polychloroprene can be sulfur modified or mercaptan modified to provide specific desired properties
Cancarb
April 15, 2017

36. Properties of Polychloroprene (CR)
Polychloroprene Rubber:
Crystallizes on stretching, allowing for:
High gum tensile strength; similar to Natural Rubber (NR)
Very good fatigue resistance
When sulfur modified, will provide:
Excellent fatigue resistance
Highly resilient compounds
High tear resistance
When mercaptan modified, will provide:
Better raw polymer stability
Good resistance to heat
Good resistance to compression set
Cancarb
April 15, 2017

37. Applications of Polychloroprene
Common applications of polychloroprene rubber are:
Adhesives – polarity-bonding
V-belts – tack and fire resistance
Timing belts – tack and fire resistance
Bellows – high flexibility
Automotive seals
Bridge bearing pads – good dynamic properties and ozone resistance
Wire and cable – resistance to abrasion, oil, flame and weathering resistance
Hose (especially covers) – good weathering resistance
Cancarb
April 15, 2017

38. The Thermax® Advantage in Polychloroprene Rubber Compounds
Thermax® will not degrade the inherently good mechanical properties of polychloroprene
Thermax® lowers the compound viscosity which is essential for lower heat build-up during extrusion and good mold flow
Thermax® will maintain the good compression set of the polychloroprene rubber
Higher loading of Thermax® is possible resulting in a lower rubber content which decreases oil swell and reduces the compound cost
Cancarb
April 15, 2017

39. Polychloroprene Compound Example Using Thermax®
Wiper Blade Compound
Neoprene WRT 60
SMR CV
ZnO 5
MgO 4
Stearic acid 2
Thermax® N
SRF 20
Paraffinic Oil 2-3
DPG 0.5
TMTD 0.5
Sulfur 1.0
6 PPD 1.5
TMQ 1.5
MC Wax 2
Hardness 60
High loading of Thermax® reduces the polymer content (cost savings) which helps for low noise and gives a “clean” product & surface finish 39
Cancarb
April 15, 2017

40. - (CF2-CH2)X - (CF-CF2)Y - (CF2-CF2)Z
Fluoroelastomers (FKM)
Fluoroelastomer Structure
- (CF2-CH2)X (CF-CF2)Y (CF2-CF2)Z
CF3
VF2
Vinylidine
Fluoride
HFP
Hexafluoropropylene
TFE
Tetrafluoroethylene
Cancarb
April 15, 2017

41. Fluoroelastomers - FKM
Fluorocarbon elastomers are a very popular choice for difficult sealing applications
Fluoroelastomers are created by substituting fluorine for hydrogen on a carbon-based macromolecule
Unlike hydrocarbon rubbers, which are non-polar, the presence of fluorine creates polar molecules
Fluoroelastomers are expensive and difficult to process due to their relatively high molecular weight
Cancarb
April 15, 2017

42. Properties of Fluoroelastomers
Can be compounded to provide high heat resistance and thermal stability
Have excellent oil & gasoline resistance
Have excellent hydrocarbon-based solvent resistance
Have very good impermeability
Are flame resistant
Are resistant to weathering
Have excellent compression set resistance
Are expensive
Tend to have high Mooney viscosities which accelerate heat build-up when mixing
Cancarb
April 15, 2017

43. Applications of Fluoroelastomers
Common applications of Fluoroelastomers are:
Automotive – Valve Stem Seals, Shaft Seals, ‘O’ Rings
Aerospace – ‘O’ Rings for Hydraulic, Lubricating and Fuel Systems
Oil Field – Packers & Blow-out Preventers
Industrial – Expansion Joints in Mines, Gaskets, Valve & Pump Linings
Hoses – Fuel Lines, Turbo Chargers, Bio-diesel
Cancarb
April 15, 2017

44. The Thermax® Advantage in FKM Compound Applications
High loadings of Thermax® will not reduce the excellent compression set and low swell inherent to FKM
Excellent for ‘O’ ring and seal applications
The higher loading ability of Thermax® improves the impermeability of the compound
The best choice for fuel line hose veneer
The specific gravity of Thermax® is similar to that of FKM, so higher loading of Thermax allows for the same volume of compound to be produced while using less of the expensive FKM elastomer, without sacrificing the desired compound properties.
Overall compound cost reduction
Cancarb
April 15, 2017

45. FKM Compound Example Using Thermax®
FKM O-ring
Compound 1
Compound 2
Dyneon FC
Maglite D
Calcium Hydroxide
SRF
Thermax® N
Press cure cure
Tensile Strength (psi)
Elongation at Break (%)
Shore A Hardness
Air Ageing 70 hrs/276°C
Tensile Strength (psi)
Elongation at Break (%)
Shore A Hardness
Compression set (%)
- Method B (0.139” O rings) 70 hrs/200°C
Thermax® enables higher loading while maintaining adequate original mechanical properties with excellent ageing properties, compression set resistance and low swell 45
Cancarb
April 15, 2017

46. Ethylene Propylene Diene Rubber (EPDM)
Structure
CH3 |
CH2 = CH2 + CH = CH2 + A Diene Monomer
Ethylene
Propylene
Diene Monomers Used in EPDM
DCPD - dicyclopentadiene
ENB - ethylidene nobornene
VNB - vinyl norbornene
Typically, ethylene comprises 45% to 80% of the polymer with the diene making up 2.5% to 12%. 46
Cancarb
April 15, 2017

47. Ethylene Propylene Diene Rubber (EPDM)
Increasing the ethylene content in EPDM provides:
Improved cold green strength
Excellent theroplasticity which improves extrusion and mold flow characteristics
Increased filler and oil loading ability
Higher heat resistance
Good cured tensile strength properties
But:
It is responsible for less building tack
It is more difficult to mix
Mill processing at low temperatures is difficult
Compression set and recovery in cold temperatures is poor
Flex resistance and elastic recovery are reduced 47
Cancarb
April 15, 2017

48. EPDM – Molecular Weight Distribution
EPDM Polymer can be produced with a range of Molecular Weight Distribution (MWD).
High molecular weight distribution EPDM provides for:
Excellent hot green strength, important for shaping and continuous vulcanization
High collapse resistance critical for hollow extruded sections
Less porosity in extrudates
Excellent physical properties
Low compression set
Improved resilience
Facilitates oil and filler extension which improves the difficult processing characteristics common to high MWD polymers
Higher loading of filler for lower cost compounds 48
Cancarb
April 15, 2017

49. Ethylene Propylene Diene Rubber (EPDM)
Increasing the diene content of the polymer provides:
Shorter cure times
Higher resilience
Higher modulus
Lower compression set
Cure compatibility with unsaturated rubbers 49
Cancarb
April 15, 2017

50. Properties of EPDM EPDM based rubber offers:
Excellent weather and ozone resistance
Excellent high & low temperature resistance
Excellent water and chemical resistance
Excellent dielectric properties
But,
Poor resistance to oils and hydrocarbon solvents
Poor adhesion 50
Cancarb
April 15, 2017

51. Applications of EPDM Rubber
Automotive industry
Extruded Profiles – solid and sponge
Hoses – Radiator and Heater
Seals and grommets
Appliance Industry
Washing machine parts – gaskets, elbows and hoses
Construction Industry
Glass profiles
Flooring
Membranes
Roofing
Electrical Industry
Low and Medium voltage cabling – cable jackets
Chemical Industry
Hoses
Seals 51
Cancarb
April 15, 2017

52. EPDM Compound Example Using Thermax®
Automotive Moulded Sponge
Keltan
ZnO 5
St. Acid 1
Benzoic acid 1
Thermaxx® N
Winnofil S (Coated pptd CaCO3) 35
Sunpar
Vaselin Rotor/Roll Release
TMTD 2
MBTS 2
Sulphur 2
Benzene Sulphohydrazide 3
Benzene 1,3 Disulphohydrazide 3
ML 19
Cure time
Specific Gravity
Higher Loading reduces costs. Low compound Mooney helps efficient blowing, gives uniform cell structure 52
Cancarb
April 15, 2017

53. Metallocene EPDM Technology
The introduction of EPDM in the world market produced by Metallocene Catalyst Technology has increased the scope for the usage of Thermal Black in these rubbers considerably
EPDM produced by Metallocene Catalyst Technology has very high molecular weight compared to traditional EPDM Rubbers produced from solution and suspension polymerization technology
EPMD Rubbers with Metallocene Technology are very difficult to process when compounded with furnace blacks alone. Blending Thermax in blend with the furnace black lowers the compound viscosity allowing for easy processing without a negative affect on mechanical properties 53
Cancarb
April 15, 2017

54. The Thermax® Advantage in EPDM Compound Applications
High loadings of Thermax® can reduce the compound cost without sacrificing compression set and dynamic properties
Thermax reduces the compound viscosity which improves processing, blowing and molding properties
The very low grit level of Thermax maintains excellent surface finish and ensures a uniform cell structure in sponge applications.
The excellent dispersion of Thermax results in consistent heat transfer throughout the extrusion and uniform cooling 54
Cancarb
April 15, 2017

55. Chlorosulfonated Polyethylene Rubbers (CSM)
Structure
- (CH2-CH2)x – (CH2-CH)y – (CH2-CH)z - | Cl
SO2
Polyethylene, a low cost plastic, is chemically modified to a cross-linkable rubber, retaining some of the important properties of polyethylene such as chemical resistance and electrical properties
This polymer is almost exclusively produced by DuPont Performance Elastomers under the trade name Hypalon®. On May 7th, 2009, DuPont announced that it will cease production of Hypalon® and completely exit the CSM business 55
Cancarb
April 15, 2017

56. Properties and Grades of CSM
Excellent resistance to weather, ozone, sunlight, oxidation, alkalies and acids
Good resistance to oil and gasoline
Good flame resistance, abrasion resistance
It is close to polychloroprene in most properties but superior in resistance to acids, alkalies, solvents, Ozone and oxidation with better color stability
Grades
Depending on the Cl content, range 24% to 43%, ‘S’ content around 1%, varying Mooney
Increasing Cl content give oil and flame resistance 56
Cancarb
April 15, 2017

57. Applications of CSM Rubbers
Grade Cl content (%) Mooney Viscosity
ML 100°C
Hypalon 40/40S /45
Hoses
W & C
Rolls
Hypalon
Low Temp. Applications
Hypalon 48/48S /62
Excellent oil resistance
low permeability to Freon
Air Conditioner Hoses 57
Cancarb
April 15, 2017

58. + Butyl Rubber (IIR) Structure CH3 | CH3 |
- CH2 – C CH2 – C = CH - CH2 - + |
CH3
Isobutylene
Isoprene
Butyl Rubber is a copolymer of isobutylene and a small amount of
Isoprene, typically around 2%
Chlorobutyl (CIIR) and bromobutyl (BIIR) rubbers are produced in a similar manner, but with and additional halogenation stage required 58
Cancarb
April 15, 2017

59. Properties of Butyl Rubbers
Presence of “bulky” isobutylene groups causes slow movement of the polymer chain which gives butyl rubber excellent impermeability to air, oxygen and water
-CH3 groups along the chains interfere with each other, reduce the speed with which the molecules
Low unsaturation makes Butyl more resistant to heat ageing and to attacks by acids, alkalis, oxidizing agents, ozone, water and steam, than general purpose polymers such as SBR, BR and NR
Butyl rubber is very similar in structure to polyisobutylene and has a similar glass transition temperature (Tg) of -70°C
Butyl has low resilience and very poor resistance to compression set, oil and hydrocarbon based solvents
Low unsaturation slows the compound cure rate and reduces Butyl’s compatibility with the more unsaturated rubbers such as NR, SBR and BR. Even small amount mixed in with these rubbers gives a disastrous effect on compound properties 59
Cancarb
April 15, 2017

60. Halobutyl Rubber Isoprene Halobutyl
-CH2-C=CH-CH2-
CH3 |
(-CH2-C-CH-CH2-) X
+ (X ) - +
CH2 ||
+ (HX)
X=Cl or Br
Add X2
Minus H
Virtually all halogenation takes place at the isoprene portions of the IIR Chains which represent approximately 2.0 mole% of the IIR Co-Polymer
Commercial chlorobutyls contain 1.1 to 1.3% weight of chlorine and bromobutyls contain 1.9 to 2.1% weight of Bromine
Stearic hindrance of the double bond favors substitution rather than addition, so most of the unsaturation is retained, although it is now largely isomerised 60
Cancarb
April 15, 2017

61. Butyl versus Halobutyl Rubber
Butyl rubber Chlorobutyl Bromobutyl
Cure reactivity
Compatibility with other unsaturated rubbers
Tack
Cure adhesion with other rubbers
Increased cure compatibility reduces the need for stringent precautions against contamination with other unsaturated rubbers
Flexibility and resistance to dry heat are almost identical for both Chloro and Bromobutyl rubber 61
Cancarb
April 15, 2017

62. Permeability of Halobutyl
Typical Tire Inner Liner Compound
Permeablility rates at 65°C Air Moisture
100% NR
100% SBR
HIIR/NR (60:40)
100% HIIR
The excellent permeability of Halobutyl rubber makes it a very popular choice for tire inner liners 62
Cancarb
April 15, 2017

63. Applications of Butyl and Halobutyl Rubber
Inner tubes for tires (IIR, HIIR)
Heat resistant conveyor belts (HIIR)
Tire Inner liners (HIIR)
Tank linings (HIIR)
Side Walls (HIIR)
Dampers/bridge bearing pads (IIR/HIIR)
Tire curing bladders (HIIR)
Adhesives/sealants (cross-linked IIR, HIIR)
Steam/Automotive Hoses (HIIR)
Pharmaceutical closures (HIIR) 63
Cancarb
April 15, 2017

64. The Thermax® Advantage in IIR & HIIR Compound Applications
High loadings of Thermax® can reduce the overall compound cost without a significant loss in compound properties
The higher loading ability of Thermax® improves the impermeability of the compound by replacing polymer with impermeable filler
Thermax can raise the viscosity of the compound making it easier and less expensive to process
Improved adhesion can be achieved with Thermax® which is very important for inner liner and other rubber to rubber bonding applications. 64
Cancarb
April 15, 2017

65. Questions & Answers
Cancarb
April 15, 2017