Abstract: Cationic emulsions of bituminous binders of the type consisting of an organic phase formed of a bituminous binder dispersed in an aqueous phase containing a cationic emulsifying agent and an acid.The bituminous binder is a bitumen-polymer type binder and the acid present in the aqueous phase is a possibly hydroxylated mono or polycarboxylic acid, used in sufficient quantity that the pH of the said aqueous phase is comprised between 1 and 7.The bituminous binders of the bitumen-polymer type having passed through the said emulsions present an excellent aging behavior.

Abstract: Bitumen-polymer compositions are prepared, by mixing, at between 130.degree. C. and 230.degree. C., a bitumen with a styrene and conjugated diene copolymer and a sulphur source, the copolymer and the sulphur source being added to the bitumen either directly, or in the form of a mother solution in a hydrocarbon oil, then by maintaining the whole under stirring at between 130.degree. C. and 230.degree. C. for at least fifteen minutes.By way of sulphur source is used 0.005 to 15% by weight, with respect to bitumen, one or several polymeric or not, cyclic or linear polysulphides, and especially ditertiododecyl or dinonyl pentasulphide. The bitumen-polymer compositions obtained can be used for the obtention of superficial road coverings and present a constant quality of its properties.

Abstract: Bitumen-polymer compositions are prepared, by mixing, at between 130.degree. C. and 230.degree. C., a bitumen with a styrene and conjugated diene copolymer and a sulphur source, the copolymer and the sulphur source being added to the bitumen either directly, or in the form of a mother solution in a hydrocarbon oil, then by maintaining the whole under stirring at between 130.degree. C. and 230.degree. C. for at least fifteen minutes. By way of sulphur source is used 0.005 to 15% by weight, with respect to bitumen, one or several polymeric or not, cyclic or linear polysulphides, and especially ditertiododecyl or dinonyl pentasulphide. The bitumen-polymer compositions obtained can be used for the obtention of superficial road coverings and present a constant quality of its properties.

Abstract: A process for improving the properties of a bitumen which comprises mixing the bitumen with from about 5 to 20% by weight based on the bitumen, of a polyolefin wax at an elevated temperature for a period of time necessary to form a homogeneous mixture. The modified bitumen is particularly useful as a binder in asphalt to be used for casting.

Abstract: This invention relates to a new process for the preparation of improved polymeric bitumens.The process is characterized by preparing a first composition by admixing a petroleum fraction (160.degree.-230.degree. C.), while stirring, at a temperature of from 80.degree. C. to 120.degree. C., with a copolymer made of styrenic blocks and dienic blocks such as a styrenebutadiene disequenced or multisequenced or statistical copolymer having a molecular weight varying between 30,000 and 300,000 and crystallized sulfur which is not chemically bound.When homogeneity is obtained, a portion of said first composition is admixed for at least 15 minutes at a temperature of from 130.degree. C. to 230.degree. C., with a conventional bitumen (penetration 20-220) to form a fluid polymeric bitumen.The fluid polymeric bitumen obtained by the process of the present invention is an excellent product characterized by superior properties and this product can be used in conventional spreading means when applying coatings onto roads.

Abstract: The invention is related to new bitumen compositions having improved rheological properties.The compositions are characterized in that they contain:90 to 99.9% in weight of a bitumen, its softening point being comprised between 20.degree. and 120.degree. C.,0.1 to 10% in weight of a norbornene polymer, its average molecular weight being between 1,000,000 and 3,000,000.The compositions of the invention are used particularly as superficial coats in road surfacing.

Abstract: In a first step of the method, the gas mixture to be treated is injected into a column swept by a continuous stream of carrier gas and containing a suitable selective solid adsorbent until saturation of this latter by the adsorbed constituent of the gas mixture. In a second step, small quantities of the mixture to be treated and representing a fraction of the quantity injected into the column during the first step are injected periodically so as to collect successively at the column outlet a fraction which is enriched in the non-adsorbed constituent and a fraction which is purified in the adsorbed constituent.