EPDM sheets

EPDM is by far the most widely used material in the ballasted roofing system constmction. Because of EPDM s flexibiHty, very large sheets of up to 10,000 square feet (929 m ) can be deHvered to the job site in compact roUs that offer reduced labor on the roof in the seaming process. The typical EPDM sheet size used in ballasted systems is 12 by 30 m and 1.1 mm thick. EPDM is also widely used in both the fully adhered and mechanically fastened roofing systems. In these constmctions, both 1.1- and 1.5-mm thick material is used with widths from 2.1 to 15 m. A majority of the installations use nonreinforced sheet, although reinforced membrane can also be used in all of the system types. The majority of the reinforced sheets go into mechanically fastened systems. 

It is suggested that TOR having lower viscosity locates at the boundary of NR/EPDM layers, thereby increasing their interfacial strength. This was confirmed by measuring the adhesive strength (Ga) between NR and EPDM sheets with and without TOR as shown in Table 11.13. It is speculated that TOR is co-vulcanized with component elastomers, thereby increasing compatibility. 

Adhesive Strength between NR and EPDM Sheets with/without TOR... 

Diffusion of Liquids in EPDM Sheets with Dieeerent Percentages oe Peroxide... 

EPDM sheeting has some high level properties which gives it dominance in many diverse applications [124], These properties include excellent weather resistance and almost maintenance free life expectancy of 20 to 30 years. 

To manufacture EPDM sheeting/membrane, pre-warmed, plasticised EPDM compound at a temperature of 80-100 °C is used for calendering in a 3 roll in-line T configuration rubber calender machine or in a 4 bowl Z configuration rubber calender machine. 

EPDM is totally resistant to ozone, heat, water and UV radiation. The architects and building contractors in USA and Japan have proved how dependable this material is. A lot of flat roofs (more than 55%) are covered with EPDM sheets in these countries because of the superiority of this amazing material over conventional waterproofing substances. 

The significant characteristics of EPDM sheeting, such as, its resistance to acids and alkalies, resistance to vegetable and animal fat, being unaffected by toxic chemicals, and with good mechanical properties make its way as an effective lining barrier for effluent treatment plants. 

Trolen VP35 PP/EPDM sheets and other nonreinforced... 

An important newer use of fluorine is in the preparation of a polymer surface for adhesives (qv) or coatings (qv). In this apphcation the surfaces of a variety of polymers, eg, EPDM mbber, polyethylene—vinyl acetate foams, and mbber tine scrap, that are difficult or impossible to prepare by other methods are easily and quickly treated. Fluorine surface preparation, unlike wet-chemical surface treatment, does not generate large amounts of hazardous wastes and has been demonstrated to be much more effective than plasma or corona surface treatments. Figure 5 details the commercially available equipment for surface treating plastic components. Equipment to continuously treat fabrics, films, sheet foams, and other web materials is also available. 

Waterproof. Waterproofing barrier systems may be either hot- or cold-appHed. The hot-appHed generaUy involve a bituminous material such as asphalt used in conjunction with a reinforcing fabric such as roofing felt, cotton, or glass cloth. Cold-appHed can be bituminous or elastomeric materials either in Hquid or sheet form, with or without fabric reinforcement. Liquid elastomeric treatments include neoprene, polyurethanes, and blends of these or epoxies with bituminous materials. Among the commonly used precured elastomeric sheet materials are neoprene, polyisobutylene, EPDM mbber, and plasticized PVC. Polyethylene and PVC films and nonwoven plastic or glass fabric coated with bituminous materials also find use (78). Because these... 

In general, EPM/EPDM compounds can be extmded easily on all commercial mbber extmders. Furthermore, EPDM compounds can be calendered both as unsupported sheeting and onto a cloth substrate. 

Blends of EMA copolymer and EPDM containing vinyl norborene as a third monomer were also investigated. Blending was carried out at 180°C at a rotor speed of 100 rpm. After the reaction, the blends were quenched on the cold rolls and were sheeted out. They were examined by IR spectra. The reduction of peak area related to unsaturation indicated a progressive loss of EPDM due to reaction with EMA. The extent of reaction depended on the utilization of unsaturation which is estimated to be 14% for EMA/EPDM at a 70 30 ratio and 53% at a 50 50 blend ratio. The tensile properties exhibit synergism as the EMA proportions change from 0% to 50%. 

Sulfonated EPDMs are formulated to form a number of rubbery products including adhesives for footwear, garden hoses, and in the formation of calendered sheets. Perfluori-nated ionomers marketed as Nation (DuPont) are used for membrane applications including chemical-processing separations, spent-acid regeneration, electrochemical fuel cells, ion-selective separations, electrodialysis, and in the production of chlorine. It is also employed as a solid -state catalyst in chemical synthesis and processing. lonomers are also used in blends with other polymers. 

In the case of thermal crosslinking, the corresponding curatives were added to each of the EPDM and CR rubbers on a two-roll laboratory mill at room temperature. A constant friction ratio of 1.2 was maintained between the milling rolls. Approximately 2 mm sheets were drawn out from the mill and cured in a hot press at a pressure of 10 MPa and a temperature of 170°C and 160°C for EPDM and CR, respectively, for their corresponding optimum cure time (f90). 

As a result of its saturated polymer backbone, EPDM is more resistant to oxygen, ozone, UV and heat than the low-cost commodity polydiene rubbers, such as natural rubber (NR), polybutadiene rubber (BR) and styrene-butadiene rubber (SBR). Therefore, the main use of EPD(M) is in outdoor applications, such as automotive sealing systems, window seals and roof sheeting, and in under-the-hood applications, such as coolant hoses. The main drawback of EPDM is its poor resistance to swelling in apolar fluids such as oil, making it inferior to high-performance elastomers, such as fluoro, acrylate and silicone elastomers in that respect. Over the last decade thermoplastic vulcanisates, produced via dynamic vulcanisation of blends of polypropylene (PP) and EPDM, have been commercialised, combining thermoplastic processability with rubber elasticity [8, 9]. 

Nordel Sheet (EPDM) E.I. du Pont de 0.121 in thick sheet ethylene 25.5 C... 

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