Asphalt polymer modification

Lewandowski, L.H., Polymer modification of paving asphalt binders. Rubber Chem. Technol., 67, 447, 1994. 

MAJOR APPLICATIONS Asphalt modifiers, adhesives, sealants, coatings, footwear, polymer modifers. 

Modification of PE by chlorination is a simple technique to change the polarity, to reduce the crystallinity, and to increase the elasticity of the polymer. Partially chlorinated polyolefin waxes were reported to improve stability of asphalt-polymer blends [20, 21], so we elected to prepare and characterize polyethylenes with various degrees of chlorination to improve the polymer Interaction with polar components of asphalt. The extent of chlorination can be used to vary the crystallinity of the polymer additive. The crystalline domains of polyolefins contribute to high temperature reinforcement while their amorphous domains, which exhibit very low glass transition temperatures, contribute additional toughness and ductility at low temperatures to PO/asphalt blends, particularly those prepared from soft asphalts. 

Fig. 12-3 Complex modulus C of unmodified and 3 % SBR latex modified asphalt measured at 64 °C. The polymer modification results in 11 x increase in the elastic component, C with moderate increase in viscous component, G".

Improvement in both the rutting and cold fracture resistance of the asphalt with the polymer modification are demonstrated in Tab. 12-3 where Superpave analysis of unmodified and modified with 3 % Butonal NS175 for AAA-1 and AAK-1 (Boscan) asphalt are compared. In addition to the Superpave analysis, values of conventional measures of unmodified and modified asphalt, such as ductility (ASTM D113), penetration (ASTM D5), softening point (ASTM D36) and absolute viscosity measured at 60 °C (ASTM D2171) are also included. 

L. H. Lewandowski, Polymer Modification of Paving Asphalt Binders, Rubber Chemistry Technol. 1994, 67,447-480. 

A relatively new development which promises to gain in importance in the future is the modification of asphalt by butadiene-styrene block polymers.44 The block polymers help reduce the low temperature brittleness and impart resistance to flow at elevated temperatures. Applications in mastics, automobile body undercoatings and waterproofing materials such as high quality roofing membranes are envisaged. 

Major polymer applications hot-melt coatings, hot-melt adhesives, wall covering adhesives, paints, tubing, sporting goods, footwear, baby products, controlled release devices, wire and cable (semiconductor shields, automotive wire, automotive ignition, low-smoke cable), asphalt modification, slow burning candles, cap liners... 

Mechanical properties of asphalt can be improved [16] by modification with some polymers, especially stirene-butadiene-stirene (SBS) tri-block copolymer. SBS/ asphalt blends are prepared via dynamic vulcanization. Recycled tire crumb rubber is incorporated as a major component in its multi-layer construction [17] for a stadium field-turf. 

Uses Filler, extender for plastics, caulks/sealants, rubber, adhesives, glass, ceramics, paper, cleansers, paints/coatings, pesticides, asphalt, drilling mud, rice polishing, environmental cleanup Features Surf, modification provides more rapid and complete dispersion in polymers, higher potential filler loadings, reduced abrasion to equip., less sensitivity to moisture Properties Oil absorp. 21 Hubercarb Q 2 [Huber Engineered Materials]... 

Polymers which are used in the modification of bitumen must posses sufficient compatibility, and high thermal stability they will then be able to resist the high temperatures during the mixing process in the asphalt mixing plant, and during transport, from the... 

Anwar Parvez, M., Al-Mehthel, M., Al-Abdul, W.H.I., Hussein, LA. Utilization of sulfur and crumb rubber in asphalt modification. J. Appl. Polym. ScL 131, 1-11 (2014)... 

The combination of high cydic content, low branching, and tram unsaturation imparts Vestenamer with an unusual combination of properties compared to other elastomeric materials. The high tram content causes it to be semicrystalline in the solid state. The mixture of cydic and linear polymer chains results in relatively low-melt viscosity that makes Vestenamer useful for certain applications such as asphalt modification. 

Since the advent of asphalt paving blocks in 1824, efforts to Improve the properties of asphalt surfacing materials have centered on polymeric additives. In the 1840 s patents describing the modification of bitumen with gutta percha or natural rubber appeared and as each new polymer was developed, its potential interaction with asphalt was evaluated. Since the addition of polymers increases the cost of the corresponding polymer modified asphalt cement (PMAC), the new material must increase the durability of the mixture and meet all climatic requirements without compromise. Indeed, addition of appropriate polymers to asphalt increases fatigue cracking resistance, reduces the extent of permanent... 

The use of polymer modified asphalts for hot mix and asphalt emulsions has grown significantly in the US during the last 10 years. The National Center for Asphalt Technology (NCAT) has published a list of reasons for the use of asphalt modification [3, 4]. Asphalt has been modified to ... 

Latex, because it is an aqueous dispersion, is the ideal polymer for modification of an asphalt emulsion. Commercial availability of the cationic form makes SBR latex ideal for chip seal, slurry seal and microsurfacing applications, which are predominantly used for preventive maintenance. 

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