CS238006B1 - Polymer substances modified asphalt - Google Patents

Description

The invention relates to asphalt modified with polymeric substances such as low molecular weight polyethylene and amorphous polypropylene, styrene-butadiene rubber (SBR), thermoplastic rubber (SBS), vinyl-acetate-ethylene copolymer, respectively. mixtures thereof, characterized in that the base asphalt to be modified consists of an extraction residue obtained by propane deasphalting of an oil vacuum distillation residue, which is adjusted to the necessary properties by the addition of a heavy oil fraction of the vacuum oil distillation, or. distillation residue of vacuum oil distillation.

Increasing demands on the functional properties of asphalts, both in road construction and waterproofing, require the producer of these materials to modify the rheological properties, in particular, at lower and higher temperatures by adding polymeric substances.

These so-called modified asphalts, sprayed by the addition of high molecular weight plastomers, elastomers, plastielastoners or combinations thereof, have an increased plasticity range, higher elasticity and improved resistance to thermal and mechanical stress compared to pure petroleum asphalts produced by vacuum distillation or oxidation. They are much better suited to difficult road conditions and more demanding waterproofing conditions.

<. Currently, polyethylenes, polypropylenes, polybutadienes, various types of rubbers such as SBR and thermoplastic SBS and other suitable polymers and mixtures thereof are used to modify asphalt. These are then mixed with petroleum vacuum distillation residues or oxidized asphalts in an amount of 5 to 50 S, depending on the method and type of application.

A conventional method for producing modified asphalts is by mixing in efficient mixers at a temperature of 180 ° C, either dissolving or homogeneously dispersing the polymeric material in the asphalt.

One of the main difficulties of this process in mixing polymeric materials with asphalts produced by vacuum distillation of petroleum and oxidized asphalts is the considerable tendency of most of the polymers used to separate from the mixture, which is related to their poor solubility, respectively. dispersibility in the mentioned types of asphalts.

This phenomenon substantially limits the applicability of some types of polymers, and excludes some from use at all. This is mainly related to the chemical composition of asphalt, respectively. with a lack of aromatics in these commonly used types of asphalt.

Improvement of the miscibility of asphalts with polymeric materials such as plastomers, elastomers, plastoelastomers or mixtures thereof and the homogeneity and stability of such modified asphalts can be achieved by the production method according to the invention, required properties / softening point KK 36 to 55 ° C and penetration at 25 ° C 30 to 300 pen. units / softening petroleum constituents, eg heavy oil distillate having a viscosity of 14 to 26 mm ^ / s at 100 ° C or vacuum distillation of the oil residue with a penetration at 25 ° C of 150 to 400 pen. units.

This extract, obtained by propane deasphalting of an oil vacuum distillation residue, contains 40 to 60% of high molecular weight aromatic petroleum resins, which favorably influence the solubility and resp. the dispersibility of the polymeric substance in the asphalt and its peptization efficacy stabilize the modified asphalt structure and suppress the tendency of the polymer to separate.

At the same time, the extraction itself of propane deasphalting residues improves the cohesive and adhesion properties of modified asphalts, which is manifested by improved ductility, respectively. adhesion to aggregates.

In the following examples, a specific process for producing blends of the extraction residue obtained by propane deasphalting of a vacuum distillation residue of petroleum, adjusted to the desired properties, with polymeric materials is given.

Example 1

The modified asphalt is prepared by mixing 70% of the base asphalt, consisting of a 45% propane deasphalting extraction residue and a 55 S vacuum distillation oil residue, with a softening point of 44 ° C and a penetration at 25 ° C of 120 and 30 µl amorphous polypropylene at 180 ° C.

A homogeneous modified asphalt is obtained, suitable for example for the production of insulating strips having the following properties: softening point KK ° C 140, penetration at 25 ° C 40 pen. units, ductility 25 ° C cm 4, breaking temperature -13 ° C, bending around mandrel 0 ° C, max elongation at 25 ° C 52%.

Example 2

The modified asphalt is produced by mixing 90% of the base asphalt, consisting of 85% of the propane deasphalting extraction residue and 15% of heavy oil fraction, with a softening point of KK 46 ° C and penetration at 25 ° C of 90, and 7% low molecular weight polyethylene. 200 and 3% styrene-butadiene rubber (SBR) at 180 ° C.

A homogeneous modified asphalt for waterproofing is obtained with a softening temperature of 85 ° C, a fracture temperature of -14 ° C, a penetration at 25 ° C of 26 pen. units, max elongation at 25 ° C 350% and bending around mandrel 0 ° C.

Example 3

Modified asphalt is produced by mixing 90% of the base bitumen consisting of 50% propane deasphalting extraction residue and 50% vacuum distillation oil residue, with a softening point of KK 43 ° C and a penetration at 25 ° C of 130 and 10% SBS thermoplastic rubber at 180 ° C.

A homogeneous modified asphalt is obtained, preferably usable as an adhesive for bridge insulation and the production of insulating strips with the following properties: softening point KK 100 ° C, breaking temperature -33 ° C, penetration at 25 ° C 45 pen. units, bending around mandrel 10 ° C, max. elongation at 25 ° C 1 800%.

Example 4

The modified asphalt is prepared by mixing 85% of basic asphalt, consisting of 50% extraction residue from propane deasphalting and 50% vacuum distillation residue with a softening point of 43 ° C and a penetration at 25 ° C of 130 penetration units, and 10 S of low molecular weight polyethylene (TI = 200). and 5% thermoplastic rubber (SBS) at 180 ° C.

a homogeneous modified asphalt for waterproofing purposes is obtained, sufficiently rigid and flexible, with a softening point KK of 90 ° C, a fracture temperature of -20 ° C, a maximum elongation at 25 ° C of 700% and a bend around the mandrel of -2 ° C.

Example 5

The modified asphalt is prepared by mixing 85% of basic asphalt, consisting of 60% extraction residue and 40% vacuum distillation residue, with a softening point KK of 48 ° C and a penetration at 25 ° C of 80 pen. units, and 10 S vinyl acetate-ethylene (EVA) copolymers and 5% thermoplastic rubber (SBS) at 180 ° C.

A homogeneous modified asphalt for waterproofing and road use is obtained with a softening temperature of 74 ° C, a breaking temperature of -18 ° C, a penetration at 25 ° C of 45 pen. units, max elongation at 25 ° C 500%.

Example 6

Modified bitumen is produced by mixing 80% base bitumen consisting of 40% propane deasphalting extraction residue and 60% petroleum vacuum distillation residue with a softening point of 39 ° C and a penetration at 25 ° C of 200 penetration units and 10% low molecular weight polyethylene with a melt index TI = 200 and 7% vinyl acetate-ethylene (EVA) copolymers and 3% styrene-butadiene rubber (SBR) at 180 ° C.

A homogeneous modified asphalt is obtained with a softening temperature of KK 90 ° C, a penetration at 25 ° C of 43 pen. units, breaking temperature -20 ° C, max. elongation at 25 ° C 230%, suitable for use in waterproofing technology and road construction.

Claims (3)

SUBJECT OF THE INVENTION Polymer-modified bitumen, characterized in that it consists of 60 to 98% by weight of an extraction residue obtained by propane deasphalting of a vacuum distillate of a sulfur-paraffinic crude oil, adjusted to a softening point of KK 36 to 55 ° C and penetration at 25 ° C 30 up to 300 penetration units and 2 to 40% by weight of polymeric materials such as plastomers, elastomers, plastoelastomers or mixtures thereof. 2. Asphalt according to claim 1, characterized in that a heavy oil fraction of a vacuum oil distillation with a viscosity of 14 to 26 mm ^ / s at 100 ° C in an amount of 10 to 30 is used to treat the extraction residue obtained by propane deasphalting of the vacuum distillate oil. or a distillation residue of vacuum oil distillation having a penetration at 25 ° C of 150 to 400 penetration units in an amount of 20 to 60% by weight. Asphalt according to claim 1, characterized in that it contains as a polymer material a) a plastomer which is a low molecular weight polyethylene with a melt index of 200, amorphous polypropylene, b) an elastomer which is butadiene styrene rubber 75/25 (SBR), a thermoplastic styrene rubber. butadiene-styrene (SBS), c) a combination of polymers and (to c). Severography, n. P., MOST Price 2,40 Kčs Corrections in printed descriptions of inventions In the description of the invention for copyright certificate No. 23c 006, (PV 6415-61), point c has been omitted and point d has been switched in the subject matter of the invention. Correctly: c) The lastoelastomer, which is an ethylene tin acetate (EVA) copolymer or d) polymerization of polymers a) to c)