Single-ply roofing membranes

ASTM D4637, Standard Specification for Vulcanized Rubber Sheet Used in Single-Ply Roof Membrane, ASTM, Philadelphia, Pa. 

The single ply roof membrane industry uses various rubber-based adhesives to bond the seams at which adjacent rolls of membrane overlap. Since such roofs frequently carry 20-year warranties, maximizing adhesion is always desirable. The adhesion problem is exacerbated in that the membranes used are based on highly... 

ULDPE/CSR or CPE, dynamically vulcanized, then dispersed into fresh CSR or CPE processability, hot-weld strength, adhesion and crack resistance for single-ply roofing membranes Ainsworth, 1990, 1994... 

Single-ply roofing membrane based on cblorosulfonated polyethylene and ehloiinated polyethylene blend ... 

Vector SBS, SIS, and SB styrenic block copolymers are produced as diblock-free and diblock copolymers. The company s process to make linear SBCs yields virtually no diblock residuals. Residual styrene butadiene and styrene isoprene require endblocks at both ends of the polymer to have a load-bearing segment in the elastomeric network. However, diblocks are blended into the copolymer for certain apphcations. Vector SBCs are injection molded, extruded, and formulated into pressure-sensitive adhesives for tapes and labels, hot-melt product-assembly adhesives, construction adhesives, mastics, sealants, and asphalt modifiers. The asphalts are used to make membranes for single-ply roofing and waterproofing systems, binders for pavement construction and repair, and... 

Single-ply membranes offer the widest range of systems in the roofing industry. The three basic systems are ballasted, fuUy adhered, and mechanically fastened. From a cost standpoint, the fuUy adhered system is the most expensive to install, the ballasted system the least. The protected-membrane roofing system can be used with any of the basic systems. The specifications for these systems are pubHshed by the various manufacturers. The following gives a brief description of the roof assembhes. 

Eoss Prevention Data, Mdhered or Mechanically Mttached Single-Ply Membrane Roof Systems 1 —29, Eactory Mutual System, Norwood, Mass. 

Although the material most used for single-ply membranes is EPDM, in competition with it are several other materials— Du Pont s Hypalon (a chlorosulfonated polyethylene), its Neoprene products, and modified PVC. It is believed that future growth in the roofing market will depend on products, such as Hypalon, that are easy to handle and have good ozone resistance, and on PVCs modified with polymeric plasticizers. 

From the first introduction of plastic materials into the roof membrane in Japan and Europe as the sheet (single-ply membrane) or liquid systems, in the late 1950s, they have replaced the conventional hot-applied, built-up bituminous membrane. Single-ply membrane was introduced in USA only in the mid 1960s. 

PVC and PE have played a major role in the shift of early roof waterproofing technology and materials. After the introduction of elastomeric and other thermoplastic materials, flexible membranes of polychloroprene (Neoprene) rubber, butyl rubber and Hypalon were used. Later on, liquid PU, solvent-based liquid acrylate and liquid EPDM systems, in addition to new materials like SBS modified bitumens, were also used in the management of roofing. All fall into the single-ply family of roofing, which offers a much cleaner, safer, energy-efficient and cost-effective alternative to built-up roofs. 

In Europe, plasticised flexible PVC is the key material used in single ply membranes used to cover large flat roofs. For these applications, plasticiser systems used are mostly linear phthalates (mainly due to their low volatility and high photostability). 

Polymeric Sheets. Single-ply pol5mier roofing membranes have been available in North America since the 1950s. Many new products were introduced to the market such as polychloroprene (CR), chlorosulfonated polyethylene (CSPE), EPDM, and PVC. Unfortunately, since these products were different from the traditional asphalt, new installation techniques... 

Since little research had been reported on the application of thermal analysis (TA) methods to roofing, the committee recommended that more research be carried out to provide the technical basis for this application. The recommendation was based on research by Farlling and Backenstow and Flueler.I J These authors used TG, DSC, and DMA to characterize EPDM, PVC, and polymer-modified materials. Backenstow and Flueler reported the application of torsion pendulum analysis to characterize the above membrane materials. They concluded that TA techniques were useful for membrane characterization and should be investigated as methods for incorporation into standards. Previous work published by Cash on the use of DSC to characterize neoprene, chlorinated polyethylene (CPE) and PVC had shown that DSC could be used to identify not only the components in a single-ply sheet and the manufacturer, but also to differentiate between new and exposed materials. 

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