Flexible & Rigid PVC Modification

Dupont™ Elvaloy® resin modifiers and solid-phase (polymeric) plasticizer are the products of choice for flexible and rigid PVC modification.

Improves performance, lowers cost of rigid PVC compounds and enables the development of higher-value, flexible PVC products.

Flexible PVC Modification

For flexible PVC, Dupont Elvaloy® solid-phase (polymeric) plasticizer adds permanent flexibility, enabling the development of higher-value products such as single-ply roofing.

Dupont Elvaloy® KEE is a unique ketone ethylene ester (KEE) terpolymer supplied in pellet form to makers of durable low-slope PVC roofing membranes.

When soft, high-molecular-weight Elvaloy® KEE is mixed with a more rigid material such as polyvinyl chloride (PVC), the resulting compound becomes tougher and more flexible.

The elastomeric properties of Elvaloy® KEE are accompanied by convenient melting properties for thermoplastic processing. This makes the compound ideal for coating onto woven fabrics or scrim materials which are embedded in high-quality PVC roofing membranes to help fight against cutting, punctures or shrinkage. The thermoplastic characteristic of the compound makes heat-welding easier during installation and repair.

As a solid-phase flexibilizer, Elvaloy® KEE won't migrate out of the PVC roofing system, even when exposed to chemical pollutants such as grease or fuels. Chemicals such as these tend to extract many other plasticizers, causing membranes to lose flexibility and become brittle. The permanent flexibility and chemical resistance of roofing membranes made with Elvaloy® KEE makes them a proven performance leader in single-ply PVC roofing.

PVC roofing membranes made with Dupont Elvaloy® KEE are among the most durable, fastest to install, and easiest to maintain in the industry. Roofers experienced with thermoplastic membranes enjoy the reliable heat-welded seams and carefree performance of a strong, high-quality roofing product. Building owners who want their PVC roofing to last as long as possible, or who need extra resistance to weather and chemical attack, can specify PVC roofing made with Dupont Elvaloy® KEE terpolymer to assure decades of problem-free service.

Benefits of PVC roofing made with Elvaloy® KEE include:

  • labor-saving installation
  • strong, heat-welded seams
  • easy tie-ins
  • easy cut-outs or repairs
  • outstanding chemical resistance
  • enables light colored and cool roofing
Rigid PVC Modification

For makers of rigid PVC products, Elvaloy® resin modifiers widen the melt temperature processing window and lower PVC compound viscosity without increasing fusion time. This helps users increase extruder speed and improve the dimensional accuracy of PVC extruded profiles.

Ask for Roofing Membranes Made with Elvaloy® KEE

To make sure your roofing project has the long-lasting performance of Dupont Elvaloy® KEE, ask for it by name when preparing your bid package or getting estimates. Check the manufacturer's technical literature for properties, specifications and code approvals of their membranes containing Elvaloy®.

Descriptive terms used in the technical literature referring to Elvaloy® KEE include "ketone ethylene ester (KEE)" and "ethylene interpolymer (EIP)."

Not All PVC Roofing Contains Elvaloy® KEE

Most roofing membranes made with Elvaloy® KEE are included in a generic class called "thermoplastic," which includes PVC. However, not all PVC roofing contains Elvaloy®. Only PVC with Elvaloy® KEE has the advantage of a solid phase (non-migrating) flexibilizer to prevent embrittlement and assure easy maintenance over the service life of the installation.

Consider The Total Life-Cycle Cost of a Roofing System

The total cost of a roofing system is affected by the materials chosen, installation, maintenance and final disposal requirements over the useful life of the roof. The long-term durability and ease of working with roofing systems based on Elvaloy® KEE makes them very competitive. Efficient installation, clean and easy repairs, and delayed replacement also mean less business disruption, less occupant inconvenience, and less worry for facility managers. Specifying Elvaloy® KEE also helps assure your roof is installed by experienced, professional contractors who share your value for long-term performance. Good roofing contractors build their reputations by installing and maintaining problem-free roofing, and their skills and experience are your very best assurance of leak-free buildings, now and in the future.

Many manufacturers and installers of roofing systems using Elvaloy® KEE are mentioned in the case histories included on this web site.