CR
also Neoprene
CR (Neoprene) is polychloroprene, a chlorine-containing diene rubber cured with metal oxides, supplied in sulfur-modified G-type and mercaptan-modified W-type plus FR, FDA, low-temperature, foam and adhesive grades.
Reference datasheet — CR is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the A60-GP condition
CR grades and fills
CR is supplied in 12 conditions, soft to hard. A60-GP is the default FabDigit quotes; the values on this page are for it.
Compare all 12 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Closed-cell CR sponge / foam | Pick for wetsuits, thermal/acoustic insulation and low-force sealing foams; sheet or laminated with jersey. | 2 | 220 | 20 Shore A | |
Adhesive / latex grade CR polymer | Uncured, crystallizing polymer sold for contact cements, footwear adhesives and latex dips — not a moulding compound. | 8 | 700 | 35 Shore A | |
Flame-retardant CR | Use for cable jackets, mass-transit and mining parts needing V-0 / high LOI with ATH-Sb2O3 loading. | 12 | 300 | 27 Shore D | |
Very hard CR, Shore A 90 | Highly loaded compound for back-up rings, hard rollers and rigid pads; low elongation, low resilience. | 13 | 150 | 40 Shore D | |
Soft CR, Shore A 40 | Choose for low-closure-force gaskets, flexible bellows and vibration pads needing high deflection. | 14 | 550 | 8 Shore D | |
Hard CR, Shore A 80 | For high-pressure seals, wear pads, scraper blades and bushings where extrusion resistance matters. | 15 | 250 | 30 Shore D | |
Low-temperature CR | For outdoor seals, boots and cold-climate weather strip where CR crystallization must be suppressed. | 15 | 450 | 55 Shore A | |
CR, Shore A 50 | Soft-medium sealing compound for flange gaskets and weather strip with good conformability. | 16 | 500 | 11 Shore D | |
CR, Shore A 70 | Standard O-ring / moulded seal hardness with better extrusion and abrasion resistance. | 16 | 300 | 22 Shore D | |
A60-GPDefault General-purpose CR, Shore A 60 | Default gasket/seal/moulded-part compound; best balance of strength, elasticity and weather resistance. | 17 | 400 | 15 Shore D | |
W-type (mercaptan-modified, non-sulfur-modified) polymer base | Pick for best heat aging, low compression set and storage stability — moulded seals, hose, O-rings. | 19 | 450 | 15 Shore D | |
G-type (sulfur-modified) polymer base | Choose when tear strength, building tack and dynamic flex life dominate — belt covers, footwear, mounts. | 21 | 500 | 14 Shore D |
Supply forms, finishes and certifications
Ways CR is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
FDA | Food/FDA-compliant CR | Certification |
What is CR?
CR (Neoprene) is polychloroprene, a chlorine-containing diene rubber cured with metal oxides, supplied in sulfur-modified G-type and mercaptan-modified W-type plus FR, FDA, low-temperature, foam and adhesive grades. It combines weather, ozone and flame resistance with moderate oil resistance: 1.42 g/cm³ density, 17 MPa tensile strength, 400 % elongation and service to about 100 °C, in gaskets, hose, cable jackets and foam sheet. Oil and fuel resistance are below NBR and low-temperature flexibility is limited by crystallisation; EPDM is cheaper for weather-only sealing. CR has a density of 1.42 g/cm³ (0.0513 lb/in³), heavier than 83% of polymer grades. Its glass-transition temperature is -45°C (-49 °F). CR has a tensile strength of 17 MPa (2.47 ksi), weaker than 71% of polymer grades. Elongation at break is 400% and the elastic modulus is 0.01 GPa (7.25×10⁻⁴ Msi).
What is CR used for?
- wetsuits
- gaskets
- hoses
- cable jacketing
- adhesives
Advantages
- Good UV / weathering resistance — 85/100, better than 88% of polymer grades
- Ductile — tolerates forming and impact — 400%, better than 86% of polymer grades
- Forms and bends easily — 85/100, better than 81% of polymer grades
Limitations
- High mold shrinkage — 2.5%, worse than 93% of polymer grades
- Low stiffness — 0.01 GPa (7.25×10⁻⁴ Msi), worse than 89% of polymer grades
- Difficult to machine — 30/100, worse than 87% of polymer grades
- Absorbs moisture — dry before molding — 1%, worse than 84% of polymer grades
- Heavy — 1.42 g/cm³ (0.0513 lb/in³), worse than 83% of polymer grades
CR properties
Typical room-temperature values for CR-A60-GP; bars are the position among polymer grades.
Physical4
CR has a density of 1.42 g/cm³ (0.0513 lb/in³), heavier than 83% of polymer grades. Its glass-transition temperature is -45°C (-49 °F).
Mechanical8
CR has a tensile strength of 17 MPa (2.47 ksi), weaker than 71% of polymer grades. Elongation at break is 400% and the elastic modulus is 0.01 GPa (7.25×10⁻⁴ Msi).
Thermal8
CR is rated for continuous service to 100°C (212 °F). It conducts heat at 0.19 W/m·K (0.11 BTU/hr·ft·°F), worse than 68% of polymer grades. Thermal expansion is 200 µm/m·K (111.1 µin/in·°F).
Electrical5
CR is an electrical insulator with a dielectric strength of 16 kV/mm (406.4 V/mil) and a resistivity of 1×10¹⁰ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (80/100), worse than 52% of polymer grades. UV resistance is excellent.
Sustainability4
Producing a kilogram of CR takes about 105 MJ of energy and emits 4.2 kg of CO₂ — more than 54% of polymer grades. Typical recycled content is 5%.
Manufacturability5
CR's machinability is poor (30/100, worse than 87% of polymer grades); formability excellent (85/100).
Common Calculations4
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the polymer family
Yield strength against density for every polymer grade FabDigit runs. CR is highlighted; hover a dot for its name, or open the interactive family chart.
Working with CR
Is CR easy to machine?
Cut by steel-rule die, waterjet or knife/CNC oscillating blade; drilling and turning need sharp tools, freezing or grinding wheels because the rubber tears and heats up.
Can CR be welded?
Not thermally weldable once vulcanized — join by CR contact cement, hot vulcanized splicing, or overmoulding onto an uncured layer.
Can CR be formed, bent or molded?
Mill/internal-mixer compounding then compression, transfer or injection moulding, extrusion or calendering; press cure typically 150–180 °C with metal-oxide/thiourea systems, post-cure for low compression set.
CR chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| polychloroprene (2-chloro-1,3-butadiene polymer contains ~40 wt% chlorine; ASTM D1418 designation CR | 40 – 65 | 55 |
| carbon black (N550/N774 type)reinforcing filler; replaced by clay/silica/CaCO3 in light-coloured grades | 10 – 40 | 25 |
| plasticizer / process oil (naphthenic, eesters used for low-temperature grades | 3 – 20 | 10 |
| ZnOcure activator / HCl acceptor | 3 – 6 | 5 |
| MgOacid acceptor, scorch control | 2 – 5 | 4 |
| accelerators, antioxidant, stearic acid,ETU/thiourea or thiuram systems; sulfur only for W-type | 1 – 4 | 2 |
What surface finishes work on CR?
Surfaces can be talc-dusted, chlorinated or primer-treated for bonding and painting; molded flash removed by cryogenic deflashing, and adhesion to metal achieved with phenolic/CR bonding agents.
Equivalent designations
Standards and trade names that resolve to CR in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- Neoprene
How much does CR cost?
CR is a standard-cost polymer ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
CR — frequently asked
What is CR used for?
CR is typically used for wetsuits, gaskets, hoses, cable jacketing and adhesives. In short: balanced weather and oil resistance; flame-resistant general elastomer; standard wetsuit foam.
What is the tensile strength of CR?
CR has a typical tensile strength of 17 MPa (2.47 ksi) — weaker than 71% of polymer grades. Strength varies by condition: see the 12 listed tempers.
Is CR easy to machine?
Not especially — machinability is rated poor (30/100, worse than 87% of polymer grades). Cut by steel-rule die, waterjet or knife/CNC oscillating blade; drilling and turning need sharp tools, freezing or grinding wheels because the rubber tears and heats up.
Can CR be welded?
Not thermally weldable once vulcanized — join by CR contact cement, hot vulcanized splicing, or overmoulding onto an uncured layer.
What surface finishes work on CR?
Surfaces can be talc-dusted, chlorinated or primer-treated for bonding and painting; molded flash removed by cryogenic deflashing, and adhesion to metal achieved with phenolic/CR bonding agents.
Can CR be formed, bent or molded?
Mill/internal-mixer compounding then compression, transfer or injection moulding, extrusion or calendering; press cure typically 150–180 °C with metal-oxide/thiourea systems, post-cure for low compression set.
What is the maximum service temperature of CR?
CR is rated for continuous use to about 100°C (212 °F), and briefly to 125°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does CR cost?
CR is a standard-cost polymer ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM D1418 – Rubber nomenclature (CR) — ASTM (2022)
- ASTM D2000 – Classification system for rubber products in automotive applications (BC/BE types) — ASTM (2021)
- ISO 1629 – Rubber and latices, nomenclature — ISO (2013)
- Denka Chloroprene M/A/S series technical data — Denka Company Ltd. (2023)
- Neoprene (polychloroprene) product and compounding guides — Arlanxeo / former DuPont Performance Elastomers (2020)
- Engineered Materials Handbook Vol. 2 – Engineering Plastics & Elastomers — ASM International (1988)
- Rubber Technology (Morton), chloroprene chapter — Springer (1999)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.