Currently, there are over a hundred brands of polymer bitumen materials available in the market. There is no need to analyze them based on the product name, since any producer comes up with a new name, although the structure, composition and properties of these materials are near identical.
In general, a polymer bitumen material includes a base covered with polymer bitumen binders and protective layers on both sides. The upper layer offers protection from solar radiation, while the lower layer prevents sticking of layers in a roll.
No prize for guessing from the name: polymer bitumen binder consists of two components, bitumen and polymer. As a rule, the part of the polymer component does not exceed 12%. Modifiers raise the quality and durability of roofing materials considerably. Among the most popular additives are Styrene Butadiene Styrene (SBS), which is an artificial rubber, as well as atactic (APP) and isotactic (IPP) polypropylene.
Atactic polypropylene gives the bitumen higher heat endurance, resistance to weather and extra flexibility. Introduction of Styrene Butadiene Styrene gives even more flexibility to the binder, but at the same time makes it more sensitive to ultraviolet rays. Some other characteristics of roofing materials are also improved.
Protective coating can be fine or coarse dressing compounds.
If the material is used as the upper layer of roofing, the front surface should be dusted with coarse dressing compound, while the underside is covered with a polymer micro perforated film or a fine dressing compound.
Although the above roofing materials have similar components, structure and production technology, they differ in properties due to several factors:
- varying quality of raw materials;
- varying amount of modifiers added;
- type of modifiers applied.