Other

University of Toronto

Canadian Patents & Development Ltd.

Polyphalt Inc.

Sulphur Development Institute of Canada (sudic)

Raymond T Woodhams

Zhi-zhong Liang

Simon Adrianus Hesp

Kenneth R Tate

Marinos Xanthos

Zhizhong Liang

James W Smith

Simon Hesp

Stabilized bitumen compositions

Treatment of rubber to form bituminous compositions

Insoluble particulate materials, which may be in solid or liquid form, are dispersed in a continuous non-aqueous phase and the dispersion rendered stable and resistant to phase separation by an in-situ stabilization procedure involving the formation of chemical bonds among the stabilizer components and to dispersed phases to form a network surrounding the particles which is compatible with the continuous phase. The invention has particular application for the formation of stabilized polyolefin-modified bitumen compositions for paving and other applications.

In-situ stabilized compositions

Insoluble particulate materials, which may be in solid or liquid form, are dispersed in a continuous non-aqueous phase and the dispersion rendered stable and resistant to phase separation by an in-situ stabilization procedure involving the formation of chemical bonds among the stabilizer components and to dispersed phases to form a network surrounding the particles which is compatible with the continuous phase. The invent ion has particular application for the formation of stabilized polyolefin-modified bitumen compositions for paving and other applications.

A process for the continuous production of a high modulus article comprising a composite of an oriented plastic material and an oriented particulate material, said process including the steps of:

Oriented thermoplastic and particulate matter composite material

A process for producing a high modulus article includes forcing a high molecular weight plastic material, such as polyethylene, through a passage of which the cross-sectional area diminishes in the forward direction of plastic flow, thus producing an extrudate. The plastic material is extruded while it is close to or at its melt temperature, and it is lubricated to obtain substantially plug flow through the passage. The speed at which the plastic material flows through the passage is adjusted so that the elongational velocity gradient at any longitudinal position within the passage does not exceed about 2.6 sec..sup.-1, thus minimizing the degree of molecular orientation in the extrudate. The extrudate can be deformed by drawing while it is maintained at or close to its melt temperature, thus producing an oriented, deformed extrudate. The oriented extrudate is then quickly cooled to preserve the orientation. A suitable plastic material is high molecular weight polyethylene with an average molecular weight lying between about 500,000 and about 1,500,000.

Process for the continuous production of high modulus articles from high

A stabilizer for bitumen-polymer compositions. Polyethylene-bitumen compositions having the polyethylene component dispersed throughout the solution and stabilized against gross phase separation are described. A method for preparation of the stabilizer includes vulcanization of a bitumen and amine-terminated poly(butadiene-co-acrylonitrile). Carboxylated polyethylene is coupled with the vulcanization product to obtain the stabilizer. Polyethylene dispersed in bitumen containing the stabilizer does not undergo gross phase separation and droplets in the 1 to 5 micron range are observed microscopically.

Bitumen-polymer stabilizer, stabilized bitumen-polymer compositions and

Bitumen-polyolefin compositions, e.g. for use as binders in paving compositions, are stabilized by an emulsifier system comprising a polyethylene wax terminally functionalized with acidic groups and having a polymeric main chain structure which is compatible with the polyolefin of the dispersed phase of the binder. In a preferred embodiment, the emulsifier system also includes an inorganic metal compound which will react chemically with the terminal functional groups of the polyethylene wax. Especially preferred is maleated polyethylene wax (as the polyethylene wax) and ferric oxide (as the inorganic metal compound). The emulsifier system forms a sheath of inorganic material around the dispersed polyolefin droplets, to stabilize them and to hinder their floatation to the surface of the binder composition.

Bitumen-polyolefin compositions

Mica reinforced thermoplastic composites, especially polypropylene composites, are prepared by a hot melt mixing process in which the mix contains propylene polymer waxes, in an amount up to about 10 percent by weight based upon the mica. The propylene polymer wax may be degraded, hydrocarbon isotactic polypropylene, or derivatized polypropylene wax such as maleated or sulfonated polypropylene wax. The wax has the effect of increasing the tensile strength and durability of the composite, and providing a smooth, uniform and glossy surface finish.

Reinforced resin composites

The inclusion of fibre elements in a sulphur/mineral aggregate composition, for example, a sulphur concrete or mortar, improves the fracture toughness of the composition and retards crack propagation.

Fiber reinforced sulphur concretes

Molding compounds in various forms for molding into high performance composites, are prepared from reinforcing mica platelets, preferably of high aspect ratio, and thermosetting unsaturated polyester resins. The unsaturated polyester solid and a solid vinylic monomer are blended, finely divided (e.g. to about -200 mesh), and the platelets are uniformly coated with these fine particles by dry blending. A compaction with partial coalescence of the fine resin particles in situ is carried out to densify and aggregate the coated platelets and shape the mixture. The resulting molding powders, bulk or sheet molding compounds are readily molded into the high performance composites, the platelets being substantially protected from degradation by the distributed resin.

Preparing mica-reinforced composites

Chrysotile asbestos is chemically opened into the individual fibrils by soluble vinylic polymer polyelectrolytes containing carboxylic acid groups in aqueous media. Polyacrylic acids, polymethacrylic acids, maleic anhydride polymers and water-soluble copolymers thereof are preferred polyelectrolytes and form stable colloidal dispersions. The polyelectrolytes are neutralized to alkaline pH with inorganic or organic bases, but preferably with basic vinylic monomers when complete encapsulation is desired. By a further aspect of the invention the polyelectrolyte-coated fibrils in aqueous dispersion are encapsulated by copolymerization with (a) a basic vinylic comonomer (used for pH control) such as dimethylaminoethyl methacrylate, t-butylaminoethyl methacrylate or a vinylpyridine; and (b) a non-basic vinylic comonomer such as styrene, divinylbenzene, vinyl chloride or fluoride, vinyl acetate, methyl methacrylate, ethyl acrylate, acrylonitrile, and methacrylonitrile. The encapsulated fibrils are advantageous for forming reinforced composites including laminates and foamed or cellular products.

Growing community of inventors

Toronto, Canada

Raymond T Woodhams