V3336 is a Versico Systems EPDM roofing-membrane compound designation, typically 65 Shore A, sulfur-cured, and rated for hot-membrane or peel-and-stick application. A true cross reference demands matching the underlying ASTM D2000 line callout rather than the proprietary trade name.
V3336 generally translates to ASTM D2000 type M5BA or M5CA grade, with a 65 Shore A hardness and a sulfur donor cure. Procurement teams should request the underlying callout, not the trade name, when qualifying a second source.
Defining V3336 inside an ASTM D2000 callout
ASTM D2000 line callouts are built as: material (M) + durometer hardness (5 = 65 Shore A) + tensile class (A = minimum tensile strength) + heat resistance letter. For a V3336-grade roofing compound, the practical callout is M5BA707 or similar, where the suffix digits encode the original physical-property requirements [S3].
Cross referencing on a "V3336 equivalent" basis therefore resolves to four independent specification dimensions: base polymer (EPDM, ethylene-propylene-diene, third monomer ENB or DCPD), cure system (sulfur or peroxide), hardness window (typically 60 to 70 Shore A for roofing membranes), and required aging set (heat, ozone, water, UV). Any one mismatch, particularly cure system, will change processing behavior on the calender or extruder [S3].
Building a cross-reference matrix: polymer, cure, hardness, aging
The comparison below lines up the four decision axes that determine a true V3336 equivalent. A second-source compound that matches three of four is, in practice, a different compound, not an equivalent.
Property axis 1, base polymer. EPDM is a terpolymer of ethylene, propylene, and a non-conjugated diene (most commonly ENB). ENB content drives sulfur-cure speed and is typical for membrane and weatherseal grades. DCPD grades are slower-curing and were common in older formulations. Generic "EPDM" labeling hides this difference [S3].
Property axis 2, cure system. Sulfur-cured EPDM dominates roofing, peroxide-cured EPDM dominates hot-oil and high-temperature hose. A V3336 equivalent specified for hot-membrane application must be sulfur-cured; substituting a peroxide-cured compound changes scorch behavior and storage stability of the uncured sheet [S3].
Property axis 3, hardness. V3336 sits near 65 Shore A. Roofing membranes in service range roughly 55 to 70 Shore A depending on filler load (carbon black, plasticizer oil, calcium carbonate). A 5-point swing changes the ability to wrap a parapet or to take a peel-and-stick adhesive film without cracking [S3].
Property axis 4, aging and fluid set. ASTM D2000 suffix digits call out tests for heat aging (often 70 h at 100 to 125 C), ozone resistance (typically 50 pphm, 38 C, 70 h, no cracks), water resistance, and low-temperature brittle point. For a V3336-type membrane, ozone and UV aging are the most application-critical and are commonly required at 70 h minimum [S3].
Procurement criteria: how to qualify a V3336 second source
Request the ASTM D2000 line callout, the Mooney viscosity window (typically ML 1+4 at 100 C in the 40 to 70 range for calendered sheet stock), the specific gravity, and the cure system. Without these, a supplier quote against the trade name is unverifiable [S3].
Run a side-by-side lab comparison: tensile and elongation per ASTM D412, hardness per ASTM D2240, ozone resistance per ASTM D1149, and a 70-hour heat aging at the project-specific test temperature. A 10% or greater drift in aged tensile or elongation is the typical engineering reject threshold, not a soft "we think it should be fine" judgment [S3].
For a deeper field-install perspective on the same base polymer, see this EPDM weatherseal temperature-range spec map, which sets the same ozone and low-temperature britteline tests in the narrower seal profile context.
Adjacent cross-reference resources and how to use them
Roofing-system cross-reference charts, such as the American WeatherStar EPDM restoration matrix dated 2025-05-14, are not compound-equivalent charts. They map liquid-applied coating systems (acrylic, silicone, urethane, hybrid) on top of an existing EPDM membrane, listing primer, base coat, intermediate coat, and top coat dry-film thickness (DFT) for 10, 15, or 20 year warranties. Useful for a restoration spec, not for second-sourcing the membrane itself [S1].
Adhesive-sealant cross-reference guides, such as the 3M industrial sealants chart, map sealant chemistry (PU, SMP, silicone) to competitor trade names. They are similarly a chemistry translation tool, not an EPDM-compound cross reference. For roofing, the relevant chemistry map is between tape adhesives and primer systems, not the underlying membrane [S2].
Working envelope and limits of any V3336 equivalent
EPDM in general, and V3336-family compounds in particular, are service-rated from approximately -60 F to 350 F with strong UV, ozone, and water resistance, but they are degraded by petroleum oils, and they bond poorly to metal without a specialized primer [S3].
For phosphate-ester hydraulic systems, a separate evaluation is required because phosphate esters attack sulfur-cured EPDM and call for peroxide-cured or HNBR alternatives; see EPDM seals in phosphate-ester hydraulic fluid for the fluid-side selection rules.
Selecting suppliers and tracking the right documents
Compound suppliers typically hold ISO 9001:2015 for compound manufacture, with the automotive tier also carrying IATF 16949:2016 for weatherstrip and sealing customers. A roofing-membrane V3336 equivalent does not need IATF, but does need batch-level CoA with ASTM D2000 callout, Mooney, and SG data [S4].
Trackable signals for the next qualification cycle: (1) supplier CoA format aligning to ASTM D2000 suffix digits rather than trade name; (2) lab confirm data on a 70 h ozone, 70 h heat aging, and ASTM D412 tensile/elongation set. A 10% drift on aged properties remains the working reject threshold.
Component reference pages worth checking: epdm rubber, concrete curing compound, and pressure transmitter.