Producing basic and groundless roll materials. Major manufactured by processing framework (roofing paper, asbestos paper, glass, etc.) bitumen, tar, and mixtures thereof. Groundless obtained as webs of certain thickness, using rolling mixtures composed of organic binders (usually asphalt), filler (mineral powder or shredded rubber) and additives (preservative, plasticizer). The main requirement for rolled roofing materials - water resistance, which persists only in the absence of cracks and breaks. Therefore, taking into account the working conditions of the material on the roof (a wide range of temperatures and UV radiation) and the need for plasticity during his placement (unwinding and adhering rolls) the most important indicators of quality of rolled materials are: - flexibility (measured by the minimum temperature at which no crack at the bend of the strip of material on the rod with a certain radius) - heat resistance - resistance (estimated by the effort to break the strip of material 5 cm wide). The most common rolled roofing materials include: roofing, asphalt and only. Widespread glassine and roofing material because of their adaptability: they are easy to manufacture roofing materials and devices in a wide range of angles of slope and roof structures for a variety of reasons. Such materials are used on roofs with low slope on concrete or other "continuous" basis. Traditional roofing has the form of a multilayer (three to five layers) of glassine or carpet underlayment roofing material (bottom layers) and the coating of roofing material (top layer), to be applied bituminous mastics. A more modern variant - surfaced roofing material. In this case, roofing rug plank with gas burners. At high angles of roof slope may mount roofing nails for layouts. A major shortcoming of roofs from glassine and roofing material is a low life (five to seven years), which experts explain the low strength and biopersistence paperboard, as well as brittle in the cold, low resistance to heat aging and sun-bitumen binder. With prolonged use the material becomes rigid, and roofing rug at any temperature, shrinkage strain cracking. In addition, because of the fragility of the bitumen binder in the cold and the inability to roll a roll of tar paper roofing device is impossible in the winter. It should be noted that in Western Europe, particularly in Germany, for many years bituminous materials for paperboard are forbidden to use the device for roofs. In today rolled roofing materials to improve the properties are three main areas: - modification of bitumen - a new replacement board sound and durable basis - the use of new types of reserving posypok. The easiest way to modify bitumen - the introduction of fine fillers or oxidation of molten bitumen by blowing air through it, which increases its heat resistance. But it does not increase the elasticity of bitumen and its resistance to aging. The classification of roofing materials, depending on the binder. Bituminous materials such as bitumen has a softening point of 45-50 ° C, which is too little for roofing materials. The oxidation of bitumen (hot air under pressure is passed through a bitumen) provides a higher (85-90 ° C) the level of heat resistance of the final product. In this case, however, reduced frost resistance of bitumen - a material to bend without cracking, even at 0 ° C. Materials on oxidized bitumen, being stacked on the roof, over time, oxidize at ordinary temperatures, which leads to a gradual deterioration of its properties (aging). In modern materials to reduce this effect, apply special brand of bitumen, which allows about half raise their lifetime, compared with roofing material. Having some drawbacks, the materials on oxidized bitumen have a very attractive price and very high technology. They can be successfully applied in places where there are strong temperature gradients. For example, as underlayments or for waterproofing interior (basements, bathrooms, garages). This type of material is valuable as an intermediate stage between the roofing material and polymer-bitumen materials, as possessing a very attractive price, they will redirect to the roofers roofing material to use technology fusing. Polymer-bitumen materials are more effective modified bitumen polymer products. Polymer additives can extend the operating temperature range of bitumen, reducing the temperature of its fragility, and increasing the softening point, ensure preservation of the elasticity of binder for a long time, that is, increase the durability of the material. Currently, the modification of bitumen used, mostly atactic polypropylene (APP) and styrene-butadiene-styrene (SBS). This allows a very good physical and mechanical properties combined with long life (15-25 years). - AMS. Compared with conventional air-blown asphalt, bitumen modified with APP, characterized by high heat resistance, good flexibility in cold (-20 ° C) and high resistance to weathering. Since the polymer itself is not very strong strength, its concentration should be rather high (30%) - LBS. Bitumen, SBS modified, are characterized by an even higher flexibility in the cold (-30 ° C), but they are more sensitive to UV radiation, and therefore require protection from sunlight. As a result, even a small amount of bitumen properties are much better. Usually add from 8 to 12%. Materials based on such modified asphalts have an extended range of operating temperatures, increased durability and allow for work on the device of the roof of rolled materials at low temperatures. Positive effect on the modification of asphalt binder in full can be realized only in the case of replacing a weak and short-lived cardboard base on a stronger and more persistent basis. Such a framework is obtained by using glass or synthetic fibers (primarily polyester fibers such as "polyester") in the form of fabrics, canvas and nonwoven fabrics, as well as by short segments disperse reinforcement fibers.
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