Modifiers and types of roofing bitumens

Either air blown bitumen or modified bitumen can be used for production of bitumen shingles. The question is which material is better.

Modified bitumen is a mix containing various modifiers for performance improvement. In recent years there is an emerging trend: manufacturers of roofing materials prefer modified bitumens to air blown bitumens more often than not. This approach allows to make material with high cold resistance, elasticity and severe load durability. Due to these factors, service life of roofs is extended.

Let us describe in detail the types of bitumen used for shingle production.

SBS-modified bitumen is a mix containing styrol butadiene styrol (artificial rubber). Due to this additive, the resulting product has improved flexibility and durability at subzero temperatures.

SBS- modified bitumen is fairly elastic, returning to its original shape after stretching. Among other advantages of this material there are the precize duplication of the surface shape it is applied to. Styrol butadiene styrol modifiers make bitumen insensitive to extreme temperatures.

Advantages of SBS-modified bitumens are as follows:

• ability to stretch 20 times its length without breaking;
• after stretching, only 10% of length is irreversible;
• flexibility at very low temperatures with no cracking.

The optimum content of SBS in bitumen does not exceed 3-6%. While using this material, storage and the technology of roof construction should be considered.

APP-modified bitumen, according to its physical and chemical properties, belongs to thermoplastics. This material is produced by adding atactic polypropylene to bitumen mix. APP improves high temperature endurance. One of the disadvantages of APP-bitumen is its inability to revert to initial shape after deformation.

APP material is resistant to ultraviolet exposure as well acids and alkalies. Besides, it demonstrates good adhesion to both glass and metal.

APP roofing is applied predominantly in regions with hot climate, but if applied correctly,  it can serve for a long time even in cold areas.

Air blown bitumen is produced by artificial aging of material. It is very popular in the USA. The main advantage of air blown bitumen is its high heat resistance, as well as good stability to wind loads. Properties of this material depend on the properties of the original material and the equipment used for production.

Production of modified bitumen

The quality of modified bitumen depends on the technology used for additive mixing. One of the plants which can do the job well is the GlobeCore USB unit.

This equipment can:

• operate with absolutely all currently known polymers, waxes and various specific additives;
• use various forms of modifiers: powders, granules, etc;
• implement almost any process of bitumen modification;
• inject additional amount of polymer in a product transfer mode;
• reduce your electric bill by using an oil heating system.