Polymer rubber-modified bitumen

Piazza S., Arcozzi A., and Verga G., Modified bitumen containing thermoplastic polymers. Rubber... 

According to AC 150/5370-10F, Item P-402 (FAA 2011b), the binder should be viscosity-graded bitumen (asphalt cement) with a synthetic rubber (polymer) added at a percentage of not less than 2%, by mass of bitumen. The properties of the modified bitumen should comply with the requirements of Table 5.21. 

The results of another study that looked into the effects of modifying bitumen with a range of recycled polymers have been published by Shakhnazarli and co-workers [53]. The waste rubber that was used was SBR, and the other polymers included polyamide fibres and recycled PE. A range of properties were evaluated, including extensibility, softening point and adhesion. 

The solvency of cycloaliphatic hydrocarbons is between that of aliphatic and aromatic hydrocarbons. They have a high solvency for fats, oils, oil-modified alkyd resins, styrene-modified oils and alkyd resins, bitumen, rubber, and other polymers. Polar resins (e.g., urea-, melamine-, and phenol-formaldehyde resins), as well as alcohol-soluble synthetic resins and cellulose esters are, however, insoluble. 

Bitumen modifiers can be synthetic polymers, natural rubber (latex) and some chemical additives such as sulfur and certain organo-metallic compounds. Fibres and fillers (inorganic powders) are not considered to be bitumen modifiers. Table 3.16 gives some typical bitumen modifiers, as well as significant improvements to asphalts. Polymers are the most common type of bitumen modifiers, with thermoplastic elastomers being the most popular polymer. 

The insulation system for pitched roofs usually provides the advantage of a continuous, homogeneous insulating layer with an economy in construction. Bitumen (asphalt) as well as its different versions modified with various polymers and a number of different roofing membranes, i.e., preformed or liquid applied sheets of PVC, terpolymer of ethylene-propylene-diene monomer (EPDM), chlorosulfonated polyethylene (Hypalon), PU, butyl rubber, polychloroprene (Neoprene) [36], all have been used as insulating layers. 

Polymer-modified bituminous membranes were developed in Europe in the mid- 1960s and have been in use in North America since 1975. The polymeric systems have varied from natural rubber to more complex synthetic systems sueh as block copolymers and polymer blends. Most common polymers used as modifiers are polyisobutylenes, polybutadienes, polyisopienes, styrene-butiene-monomer, styrene-butadiene-rubber, butyl rubber, ethylene-vinylaeetate (EVA), atactic polypropylene (APP) as well as natural rubber. Polymers, such as atactic polypropylene or styrene-butadiene-styiene (SBS), impart flexibility and elasticity, improve cohesive strength, resist flow at high temperatures, and toughness.1 1 They are the most widely used modifiers of bitumen-based roofing materials. 

Thanks to all these properties, the dolocarbonate seems promising for different applications, first of all for all the applications of traditional low density mineral fillers. This material could for instance be used as a component in thermal insulating materials like panels or foams, as a filler in mortars or plasters or concretes to decrease their thermal conductivity, as a filler in polymer or rubber compositions to improve their fire and/or mechanical properties, as a filler in paints, papers, cosmetic compositions, as a rheology modifier (viscosifying agent) in mineral slurries, glues, bitumen or asphalts, polymer compositions, as an ad- or absorbant in different applications such as water or flue gas treatment or even in the field of catalysis, as e.g. a catalyst support, or as a carrier for perfumes, aromas, active substances, medicines... 

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... 

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