Abstract: The present invention provides a process for the preparation of sulphur cement or a sulphur cement-aggregate composite comprising the following steps: (a) admixing at least an inorganic filler and/or aggregate and a polysulphide-containing organosilane having at least two organosilyl groups and allowing the organosilane to react with the inorganic filler and/or aggregate; (b) admixing during or after step (a) elemental sulphur with the inorganic filler and/or aggregate at a temperature at which sulphur is liquid to obtain an admixture comprising molten sulphur and inorganic filler and/or aggregate; and (c) solidifying the admixture to obtain sulphur cement or a sulphur cement-aggregate composite. The invention further provides sulphur cement or a sulphur cement-aggregate composite obtainable by such process and the use of a polysulphide-containing organosilane having at least two organosilyl groups as coupling agent in sulphur cement or a sulphur cement-aggregate composite.

Abstract: The invention provides modified sulphur prepared by admixing molten elemental sulphur with one or more olefinic sulphur modifiers, wherein at least 50 wt % of the olefinic sulphur modifiers is 5-ethylidene-2-norbornene and/or 5-vinyl-2-norbornene and wherein the total amount of olefinic sulphur modifiers is in the range of from 0.1 to 20 wt % based on the weight of sulphur. The invention further provides a product comprising such modified sulphur as binder which is prepared by admixing such modified sulphur, a filler and/or aggregate, and optionally elemental sulphur at a temperature above the melting temperature of sulphur and solidifying the mixture obtained by cooling the mixture to a temperature below the melting temperature of sulphur.