Bitumen is a fire-proof insulation fire proof. Thermoplastic elastomer-modified bitumen fire retardant mixture of bitumen, filler, a Brvmynh diphenyl ether, antimony oxide and zinc borate. Waterproofing fire in the preparation of a layer of polyester or fiberglass is impregnated with it.
Bitumen 85/100 is one of bitumen produced in the refining process of crude oil. The main application of this type of bitumen is in the construction industry. The name of this type of bitumen penetration grade bitumen 85/100 is it that in this range. One of exports of bitumen Industrial Co. is 85/100.
Asphaltene components of bitumen and black or brown solids that are insoluble in n-heptane addition to hydrogen and carbon containing large amounts of nitrogen, sulfur and oxygen. In general asphalten as highly polar aromatics complex with high molecular weight are considered. Various methods have been used to measure the molecular weight asphalten and varying amounts of 600 to 300,000, depending on the separation technique is obtained.
In 1930, it became clear Bitumen is a metal porphyrins, metal and porphyrin a combination of metals such as iron, copper, silver and magnesium porphyrins and porphyrin and ... with a heterocyclic compound with four pyrrole rings that were placed square-shaped structure analytical work the presence of iron and vanadium confirmed on the pitch. The figure below shows the structure of metal and porphyrins:
At ambient pressure distillation and vacuum distillation separates the light compounds from bitumen feed. The loss of Distillation leads to selective removal of saturates and asphaltene concentrations can be increased. Blowing air in the remaining bitumen obtained from vacuum distillation or (Fluxed vacuum residue) causes a significant increase in the amount of asphaltene and reduce the amount of aromatic compounds. The amount of saturated compounds and resins in the air blowing constant, the changes are shown in the following diagram.
Marshall left the pitch adhesion characteristics test (retained Marshall test) checked. In this test, eight species by Marshall graded aggregates and bitumen are made. These eight samples are divided into two groups of four. That empty space is equal in both groups. The more samples in a water bath kept at 60 ° C for 48 hours. Marshall stability is then measured. Marshall stability, Marshall stability of processed samples and prototypes to remain as stable Marshall (retained Marshal stability) is defined.
Lions stretched before they break down a lot "flexible" called and those who break before pulling in significant quantities "fragile" are called. BBR test unfortunately can not stretch some Qyrha to indicate failure. Final push-pull tension test directly for a bitumen at lower temperatures (between zero to minus 36 ° C) measures. A sample weights (dumb-bell specimen) in stress loaded with a fixed rate and a failure strain and change the length divided by the original length is detected. In this test, failure is defined by tension loading the sample reaches its maximum value. The fracture stress, strain at break must be at least 1 percent.
Is not responsible for the viscoelastic properties of the asphalt pavement performance is particularly big role in determining the resistance to permanent deformation and leave the game. Overall, the proportion of imported stretch of asphalt that is related to the viscosity of such irreversible (non-recoverable), an increase in temperature and loading time (loading time) increases. This effect on the part of a and b are shown. Asphalt is an example of a response to a simple tensile test shows. Tension caused by the use of time, a rapid elastic response, followed by a slight increase in tension with time shows up when times be removed. Change stretch remnants due to the viscous behavior of the material. By removing the load, elastic stretch immediately recovered and excess recovery happens remnants. This phenomenon is called the elasticity of delay (Delayed elasticity) is known. Finally, an additional tension remains that non-recyclable and this is directly due to the viscous behavior.
Polyurethane, polyether-polyester copolymers, olefin copolymers and styrenic block copolymers are thermoplastic elastomers four groups of which have proved to have the greatest potential for blending with bitumen. Thermoplastic rubber or thermoplastic elastomers styrenic block copolymers is well known that continuous polymerization styrene-Bvtady may Sequencing by N-styrene (SBS) or styrene-isoprene-styrene (SIS) to be produced. Alternatively, a precursor two consecutive polymerization of styrene and monomer block can be by the middle block with bonding agents produced by reaction. So in addition to linear copolymers, multi-arm copolymers are produced. As a branch or radial copolymer known Thermoplastic elastomers strength and elasticity (elasticity) of crosslinking molecules to obtain a three-dimensional network. This outcome by the end of the polystyrene blocks to the host separate accumulation is obtained. As Figure 5-3 shows the physical cross-linking polybutadiene or polyisoprene rubber for matrix A is created. Power terminal blocks of polystyrene polymer and the middle block material gives an exceptional stretch. At temperatures above the glass transition temperature of polystyrene (100 ° C), polystyrene becomes soft and receptive weak and even pressure will be separated and will facilitate processing. After cooling again host joins strength and elasticity is restored thermoplastic or thermoplastic materials are the means.
Hardening oxide and evaporating a thin film of bitumen in relation to grain mix done by two tests: test the storage of hot mix asphalt production equipment and changes in the softening point of bitumen. Test storage of hot mix during mixing and storage conditions of aging in check.. Aging bitumen during mixing and storage stored by the difference between the softening point of bitumen and the original expression.