Rubber & Elastomers•Oil & Fuel Resistant Elastomers•

VERIFIED(Source-Verified)

Chloroprene Rubber (CR / Neoprene)

Primary Designation:ASTM CR

Aliases:

NeoprenePolychloropreneBaypren

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Data Completeness:0 composition elements and 1 condition-specific property values cataloged.

Omitted fields represent unverified properties. "Missing is better than invented."

Key Engineering Properties

Representative source rows, qualified by their reported conditions. Inspect the tables below for all values, limits, and source notes.

Service Temp Range

-35°C to 100°CContinuous Limit

Continuous service typically between -35...

Engineering Summary

Chloroprene Rubber (CR)—commonly known by the historical commercial trademark Neoprene (a registered trademark of DuPont Performance Elastomers)—is a polymer of 2-chloro-1,3-butadiene. Chloroprene is widely regarded as the original "all-around" engineering elastomer due to its balanced combination of moderate petroleum oil resistance, good ozone and weathering resistance, natural flame resistance (due to the presence of chlorine in the polymer backbone), and excellent mechanical toughness. It forms strong bonds to metals and fabrics and exhibits good resistance to dynamic flex cracking.

Chloroprene Rubber (CR / Neoprene) Documented Applications

›Automotive constant-velocity (CV) joint boots, steering rack bellows, and dust boots
›Industrial electrical cable jackets, heavy-duty mining trailing cable sheaths, and marine cordage
›Elastomeric structural bridge expansion bearings and building architectural window gaskets
›Industrial V-belts, synchronous drive belt backings, and conveyor belting
›Marine wet-suit thermal sheet, diving equipment, and closed-cell vibration-damping foam

Recognized Aliases

Source-backed commercial trade name and short designations cataloged in canonical data.

NeoprenePolychloropreneBaypren

Elastomer Technical Profile • Chloroprene Rubber (CR / Neoprene)

ASTM D1418: CRISO 1629: CRASTM D2000: Type BC / BE

Polymer backbone: Polychloroprene (2-chloro-1,3-butadiene). Thermoset and cast elastomer mechanical, thermal, and chemical behavior depends strongly on compounding ingredients, crosslink density, and curing system.

Key Engineering Advantages

•Balanced, multi-purpose profile combining moderate oil resistance with good outdoor weatherability
•Inherent flame retardancy (self-extinguishes upon removal of open ignition source)
•Excellent resistance to flex cracking, dynamic mechanical tearing, and puncture
•Strong adhesion to metallic structural inserts, fabrics, and brass components
•Good resistance to refrigerants (CFCs, HCFCs) in legacy refrigeration systems

Engineering Limitations & Risks

•Only moderate petroleum oil resistance; inferior to NBR in aromatic fuels and gasoline
•Propensity to crystallize and harden upon prolonged exposure to cold temperatures (0°C to -10°C)
•Higher compound density and cost than general-purpose hydrocarbon rubbers (NR, SBR)
•Attacked by strong oxidizing acids, esters, ketones, and chlorinated solvents

Thermal Operating Limits & Service Profile

Min Continuous-35°C

Max Continuous100°C

Max Intermittent / PeakNot specified

Note: Continuous service typically between -35°C and +100°C (-31°F to +212°F) per Parker ORD 5700 Section II (Figure 2-3). Standard grades undergo reversible crystallization stiffening around -10°C unless cold-resistant grades (e.g. Neoprene WRT) are specified. ASTM D2000 heat-aging test temperatures (70h at 100°C for BC/BE) serve classification rather than continuous service ratings.

Chemical & Environmental Media Compatibility (Engineering Selection Guide)

Parker ORD 5700 Selection Ratings

Ratings represent manufacturer engineering fluid selection guidance (Parker ORD 5700 / producer design manuals). They do not substitute for batch-specific ASTM D471 / ISO 1817 laboratory immersion testing under service temperature, pressure, and dynamic stress.

Atmospheric Ozone & WeatheringSignificantly more resistant to ozone cracking than unprotected NR or SBR

GOOD

Petroleum Oils & LubricantsModerate swelling; suitable for intermittent splash contact, inferior to NBR for continuous immersion

FAIR

Water & Aqueous Salt SolutionsExcellent marine seawater resistance; used extensively in offshore bumpers and wet suits

GOOD

Gasoline & Light FuelsExcessive volumetric swelling and extraction in automotive fuels

POOR

Ketones & AcetoneRapid swelling and softening in polar solvents

POOR

Dilute Acids & AlkalisGood resistance to mild chemical splash and washdown

GOOD

Compounding & Physical Property Context

Compounding Dependency: Polymer type (sulfur-modified G-types vs mercaptan-modified W-types) determines processing and tear resistance. W-types offer superior storage stability and lower compression set; crystallization-resistant grades (WRT) eliminate low-temperature hardening.

Gas & Fluid Permeability: Moderate gas permeability; superior barrier performance compared to natural rubber, inferior to butyl rubber.

Abrasion Endurance: Good dynamic abrasion resistance in tough environments; standard material for heavy mining trailing cable jackets.

Tear Resistance: Good ASTM D624 Die C tear strength with outstanding resistance to cut growth under dynamic flex fatigue. (Not directly comparable to trouser tear Die T).

Compression Set (ASTM D395): Good compression set resistance at moderate temperatures; suitable for structural elastomeric bearings.

Chloroprene Rubber (CR / Neoprene) Specifications & Designations

Standard Designations & Applicable Specifications — Semantically classified designations distinguishing primary standard identifiers, commercial trade names, and applicable specification references.

Direct Standard DesignationsDIRECT DESIGNATION

3 Primary Identifiers

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System	Identifier	Standard System Name	Classification Notes & Provenance
ASTMPRIMARY	CR	ASTM D1418 Nomenclature	—Ref: Standard Practice for Rubber and Rubber Latices—Nomenclature (ASTM D1418-22) / Rubber and latices—Nomenclature (ISO 1629:2013)
ISO	CR	ISO 1629 Nomenclature	—Ref: Standard Practice for Rubber and Rubber Latices—Nomenclature (ASTM D1418-22) / Rubber and latices—Nomenclature (ISO 1629:2013)
ASTM-D2000	Type BC / BE	ASTM D2000 Classification System	Classified under ASTM D2000 as Type BC (100°C 70h test, medium oil swell) or Type BE (100°C 70h test, lower oil swell); accelerated test temperatures serve classification and do not constitute continuous service ratings.Ref: Standard Classification System for Rubber Products in Automotive Applications (ASTM D2000-21 / SAE J200:2021)

Recognized Commercial Aliases & Trade NamesCOMMON ALIAS

3 Listed

Scroll horizontally for full alias classifications

Recognized Name / Alias	Classification	Technical Usage & Context
Neoprene	Commercial Alias	Colloquial or commercial industry synonym
Polychloroprene	Commercial Alias	Colloquial or commercial industry synonym
Baypren	Commercial Alias	Colloquial or commercial industry synonym

Applicable Specifications & Product Form ReferencesSPECIFICATION REFERENCE

3 Applicable Standards

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Standards Body	Specification Code	Specification Title / Scope	Relationship Type
ASTM International	ASTM D1418	Standard Practice for Rubber and Rubber Latices—NomenclatureSTANDARD · Edition: ASTM D1418-22	Specification Reference
ISO	ISO 1629	Rubber and latices — NomenclatureSTANDARD · Edition: ISO 1629:2013	Specification Reference
ASTM International	ASTM D2000	Standard Classification System for Rubber Products in Automotive ApplicationsSTANDARD · Edition: ASTM D2000-21	Specification Reference

Engineering Notice: Applicable specifications establish manufacturing requirements, dimensional tolerances, and test criteria for specific product forms (e.g. bus bar, wire, plate, pipe). They represent applicable technical standards, not alternative or equivalent alloy grades.

Chloroprene Rubber (CR / Neoprene) Mechanical Properties

Contextual Mechanical Properties & Tempers: Engineering strength, ductility, and hardness values grouped by product form, temper, and section thickness. Mechanical properties are contextual and not isotropic averages.

Showing 1 of 1 conditions

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Product Form	Temper / Condition	Section Size	Tensile (UTS)	Yield Strength	Elongation	Shear Strength	Fatigue Strength	Hardness (Scales Preserved)	Status
Standard Product Form	Standard General-Purpose Industrial Vulcanizate (Mercaptan-Modified) · 100 °C Source values and qualifiers Compression Set (22h at 100°C): 15–35 % (RANGE)Good compression set resistance; adequate for moderate-temperature seals and bridge bearings.ASTM D395 Method B / ISO 815-1Parker Hannifin Corporation, Engineered Materials Group — Parker Hannifin Corp. Catalog ORD 5700 (2018/2023), Section II (Basic O-Ring Elastomers: Table 2-2 & Figure 2-3), Section VII (Compatibility Tables) / ASTM D395-18 Method B	—	—	—	—	—	—	—	VERIFIED

Hardness Integrity Notice: Rockwell B (HRB), Rockwell F (HRF), and Superficial 30T (HR30T) scales are reported on their measured scales without cross-scale mathematical conversion.

Source: See fact-level citations

Chloroprene Rubber (CR / Neoprene) Processing & Fabrication

Machining, joining, forming, and thermal processing ratings cataloged from the cited authoritative technical reference.

Source: Maurice Morton (Ed.), Springer Science+Business Media

Machinability

Cryogenically turned, ground, or die-cut with heavy steel dies; cleanly cut with CNC waterjet.

Heat Treatment & Working Ranges

Cured via metallic oxide crosslinking (5 phr ZnO + 4 phr MgO) with organic accelerators (ETU, TMTD) at 150°C to 170°C. Sulfur-modified grades use sulfur bridges; mercaptan-modified grades use carbon-carbon links.

Forming & Cold Working

Milled on standard rubber processing machinery; compounded with metal oxides (zinc oxide and magnesium oxide) rather than sulfur. Extruded, calendered, and compression/injection molded.

Chloroprene Rubber (CR / Neoprene) Equivalent & Comparable Grades

Comparable Grades & Cross-References: Carefully classified cross-reference relationships for Chloroprene Rubber (CR / Neoprene). Comparable does not mean equivalent.

Scroll horizontally for relationship classifications & comparisons

Related Material	Family	Relationship Classification	Metallurgical Notes & Differences	Status	Action
Nitrile Butadiene Rubber (NBR)	rubber-and-elastomers	Commonly Compared	NBR offers superior petroleum oil and fuel resistance; CR provides superior ozone/weathering resistance and flame retardancy.Materials serve different design priorities (e.g. higher strength vs superior corrosion resistance or cost).	VERIFIED	Side-by-Side Compare →
Ethylene Propylene Diene Rubber (EPDM)	rubber-and-elastomers	Commonly Compared	EPDM provides superior weather/ozone endurance and higher steam resistance; CR provides moderate petroleum oil resistance and self-extinguishing flame properties where EPDM would dissolve or burn.Materials serve different design priorities (e.g. higher strength vs superior corrosion resistance or cost).	VERIFIED	Side-by-Side Compare →

Related Engineering & Metallurgy Guides

Contextual technical guides explaining degradation mechanisms, testing methodologies, and selection criteria relevant to Chloroprene Rubber (CR / Neoprene).

Material Selection18 min read

Types of Rubber: Elastomer Classification, Chemical Resistance & Selection Guide

Selecting the correct rubber is not a matter of choosing a generic flexible polymer—it requires matching molecular backbone chemistry to service temperature, chemical media polarity, dynamic fatigue, and compression set. This engineering guide classifies the 11 primary elastomer families, detailing their ASTM D1418 / ISO 1629 designations, mechanical performance envelopes, and rigorous selection algorithms.

Author: MatGrades Materials Engineering GroupRead Guide →

Material Selection17 min read

What is EPDM Rubber? Properties, Chemistry, Roofing vs Engineering Specifications

EPDM (Ethylene Propylene Diene Monomer) is the global benchmark elastomer for outdoor weathering, hot water, and automotive cooling systems. Its exceptional resistance to atmospheric ozone and steam degradation stems from an entirely saturated polyalkylene backbone with crosslinkable double bonds located exclusively on pendant side groups. This guide breaks down the chemical physics, curing kinetics, and standards governing EPDM specification.

Author: MatGrades Materials Engineering GroupRead Guide →

Material Selection18 min read

Natural Rubber vs Synthetic Rubber: Resilience, Fatigue, Chemistry & Industrial Trade-offs

Despite over a century of synthetic polymer synthesis, natural rubber remains indispensable in modern heavy engineering. Its unique ability to undergo instantaneous strain-induced crystallization grants it dynamic tear strength and fatigue endurance that synthetic random copolymers cannot replicate. However, when service conditions introduce petroleum fuels, atmospheric ozone, or temperatures exceeding 80°C, synthetic elastomers become mandatory. This guide examines the macromolecular physics and industrial trade-offs governing selection.

Author: MatGrades Materials Engineering GroupRead Guide →

Sources

Sources & Provenance Trail: Authoritative reference publications, standards specifications, and data registers cited across this material record.

ASTM International, ISO & Elastomer Engineering Technical CommitteesParker O-Ring Handbook (Catalog ORD 5700) & Elastomer Engineering Selection Guide

Development BenchmarkSTANDARDS ORG

Global engineering seal benchmark establishing continuous operating temperature envelopes (Figure 2-3), elastomer property comparisons (Table 2-2), ASTM D395 Method B compression set benchmarks, and manufacturer engineering fluid compatibility selection ratings (distinguished from raw laboratory immersion coupons).

Issuing Body: Parker Hannifin Corporation, Engineered Materials GroupRevision: ORD 5700 (2018/2023)View Source Record ↗

ASTM International, ISO & Elastomer Engineering Technical CommitteesStandard Practice for Rubber and Rubber Latices—Nomenclature (ASTM D1418-22) / Rubber and latices—Nomenclature (ISO 1629:2013)

STANDARDS ORG

Authoritative international nomenclature defining rubber acronyms and classification families.

Issuing Body: ASTM International & ISO Technical Committee ISO/TC 45 (Rubber and Rubber Products)Revision: ASTM D1418-22 / ISO 1629:2013View Source Record ↗

ASTM International, ISO & Elastomer Engineering Technical CommitteesStandard Classification System for Rubber Products in Automotive Applications (ASTM D2000-21 / SAE J200:2021)

STANDARDS ORG

Standardized classification system establishing Type and Class designations and line callouts for vulcanized rubber compounds.

Issuing Body: ASTM International & SAE International Technical CommitteesRevision: ASTM D2000-21View Source Record ↗

ASTM International, ISO & Elastomer Engineering Technical CommitteesRubber Technology (3rd Edition, Maurice Morton, Ed.) & Processing Specifications

STANDARDS ORG

Authoritative scientific treatise detailing cis-1,4 strain crystallization kinetics, network polysulfidic crosslink reversion at >70°C–80°C in conventional sulfur cures vs semi-EV stabilization, and SBR reinforcement.

Issuing Body: Maurice Morton (Ed.), Springer Science+Business MediaRevision: 3rd EditionView Source Record ↗

Intellectual Property & Provenance Notice: Mat Grades cites technical literature from recognized industry associations and standards organizations. Underlying technical standards and publication data remain the intellectual property of their respective issuing organizations.