Rubber roofing material

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. 

Asphalt—mbber is mixed and applied to roadways by several techniques. In one method, mbber and asphalt are mixed at ca 175—220°C for one to two hours. The hot mixture is applied to the roadway and covered with a layer of stone chips to form a chip seal. The mbber cmmb consists of scrap tires ground into particles less than 2 mm in diameter. Rubber-modified asphalt is also used for waterproofing membranes, crack-and-joint sealers, hot-mix binders, and roofing materials. The mbber improves asphalt ductility and increases its softening point. The aggregate adhesive bond is stronger, and the asphalt lasts longer. Production of rubber-modified asphalt has increased from 405 t in 1970 to 27,000 t in 1980 (41). Typically, about 2 t of mbber is used for 1 km of roadway. If it is assumed that asphalt—mbber contains ca 25% mbber and 75% asphalt, the potential demand for scrap mbber would be ca 40,500 t/yr, or ca 2% of the amount available. 

The form of magnesium silicate hydroxide with which most people are familiar is talc, the main ingredient in talcum powder. Talcum powder is used directly as a skin treatment, especially for babies, primarily as a moisture absorbent and for soothing the skin. It is also used in a number of cosmetic products, including blushes, eye shadows, make-up foundations, and face powders. Talc is also used widely as an additive to give products a smoother texture. Some products in which it is found include paints, rubber products, roofing materials, ceramics and insecticides. Other applications of talc include ... 

The word asbestos is generally applied to two forms of fibrous natural silicates the amphiboles and serpentine. The asbestos minerals do not burn, do not rot, and have low thermal and electrical conductivity. They can be woven into fabrics, compressed into mats, and mingled with such binders as rubber and asphalt to produce strong and dimensionally stable composites. These properties have led to widespread use of asbestos in fireproofing materials, brake linings, floor tiles, pipes, and roofing materials. 

The mechanical characteristics of the bagasse-rubber roofing products are shown in Table 5. Results are for the initial material and following 1,000 hours of weatherometer exposure with cyclic UV, water spray, temperature, and humidity. The tensile strength retention of 97% is considered excellent. 

Thermoplastic rubbers (TPR) are a type of rubber produced by polymerization of a mixture of substances, such as butadiene and styrene. They have some advantages over conventional rubbers. The advantages are (a) the material can be melted and easily molded and (b) the chemical composition can be varied to improve or to produce a material with new properties with a wider range of use. Styrene-butadiene-styrene (SBS) polymer is conunonly used as a modifier in the manufacturing of asphalt-based roofing materials. 

Polymer-modified bituminous membranes were developed in Europe in the mid- 1960s and have been in use in North America since 1975. The polymeric systems have varied from natural rubber to more complex synthetic systems sueh as block copolymers and polymer blends. Most common polymers used as modifiers are polyisobutylenes, polybutadienes, polyisopienes, styrene-butiene-monomer, styrene-butadiene-rubber, butyl rubber, ethylene-vinylaeetate (EVA), atactic polypropylene (APP) as well as natural rubber. Polymers, such as atactic polypropylene or styrene-butadiene-styiene (SBS), impart flexibility and elasticity, improve cohesive strength, resist flow at high temperatures, and toughness.1 1 They are the most widely used modifiers of bitumen-based roofing materials. 

Polymers such as poly(vinyl chloride) (PVC), ethylene-propylene-diene monomer (EPDM), chlorosulfonated polyethylene, ketone ethylene ester (KEE), reinforced polyurethane, butyl rubbers, and polychloroprene (neoprene) have proven to be suitable for roofing membranes.In the last ten years, a new synthetic roofing material (thermoplastic polyolefins)... 

Paroh, R. M., and Delgado, A. H., Evaluating the Performance of Polymeric Roofing Materials with Thermal Analysis, Rubber World, 214(4) 27-32 (July 1996)... 

SELECTING A VULCANISING AGENT FOR ROOFING MATERIALS BASED ON SYNTHETIC RUBBER AND TYRE PRODUCTION WASTE... 

The possibility was investigated of using rubber waste consisting of polyisoprene, butadiene-methylstyrene and polybutadiene with machine oils and carbon black for the production of roofing materials. Mechanical properties of the resulting materials are listed. 6 refs. Articles from this j oumal can be requested for translation by subscribers to the Rapra produced International Polymer Science and Technology. 

More than 800 million pounds of EPM and EPDM polymers were produced in the United States in 2001. Their volume ranks these materials fourth behind styrene-1,3-butadiene copolymers, poly( 1,4-butadiene), and butyl rubber as synthetic rubbers. EPM and EPDM polymers have good chemical resistance, especially toward ozone. They are very cost-effective products since physical properties are retained when blended with large amounts of fillers and oil. Applications include automobile radiator hose, weather stripping, and roofing membrane. 

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