EPDM membranes manufacture

For example, more and more manufacturers, contractors, consultants, and building owners are turning to these techniques to solve in-service roofing membrane problems as well as to evaluate new roofing membrane materials. A typical example is the paper on the problem of EPDM membrane shrinkage The study was conducted in 1995 to investigate the causes of... 

Thermoplastics. There are five elastomeric membranes that are thermoplastic. Two materials, chlorinated polyethylene (CPE) and polyisobutylene (PIB), are relatively obscure. Thermoplastic materials can be either heat-fused or solvent-welded. In contrast to Hypalon and uncured EPDM, this abiHty to fuse the membranes together remains throughout the life of the material. However, cleaning of the membrane surface after exposure to weather is required. Correct cleaning procedures for specific membranes are available from the individual manufacturer. 

Antitack rubber suitable for manufacturing pneumatic tires is produced from combination of CSP and natural rabber. This composition used 3 wt% of an undisclosed plasticizer (process oil). A paper transport belt made from a blend of CSP and EPDM rabber used 3 phr of polyethylene glycol and 25 phr of dioctyl sebacate. A membrane obtained from blending CSP and chlorinated polyethylene contained 6 phr of tri-(2-etltylhexyl) phosphate. ... 

Thermoset membranes are compounded from rubber polymers. The most commonly used polymer is ethylene, propylene and a small amount of diene that is vulcanized with various accelerants. This polymer, referred to in the industry as EPDM, is commonly known as rubber roofing . Another thermoset rubber roofing material is neoprene, although this particular formulation is rapidly being replaced by EPDM. Finally, the rubber/plastic hybrid Hypalon is also considered as thermoset. Hypalon is unique in that it is manufactured as a thermoplastic but, because it cures over time, becomes thermoset. 

To meet these desirable properties, the appropriate polymer to consider would be ethylene - propylene-diene terpolymer (EPDM). In the manufacture of a cost effective, impermeable membrane system, EPDM rubber is the right choice as a discreet material for improved waterproofing and protective lining applications in roofing and other uses in the construction sectors [125]. 

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. 

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. 

The dynamic mechanical analysis results for the EPDM roof membrane samples from the three different manufacturers (SI, S2, S3) showed a similar trend to that observed by TG. The glass transition temperature (7 ) of the unheated specimens from S1 and S2 manufacturers was -49° and -46°C, respectively. The Tg of heated specimens did not change significantly (-48° to -42°C range) even after 28 days of exposure at 100° and 130°C. As predicted by TG, the EPDM specimens from the S3 manufacturer showed an increase in Tg with the number of days of heating. For example, the Tg changed from -61°C for the unheated to -46°C after 28 days at 100°C and to -43°C after 28 days at 130°C. 

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