A building material comprising an inorganic binder a reactive silicon source a reactive calcium source.

A method and device for producing lightweight panels with a core of gypsum or of cement and gypsum, with pores for decreasing volumetric weight, and with a covering made of cardboard or of a sheet of glass fibers. The production line does not change except for the addition of a device which forms closed hollow cavities within a suspension in an area where an upper sheet covers the suspension. Air pressure which is fed into the formed cavities is slightly higher than the hydraulic pressure of the suspension, so as to prevent the gaps being filled by the suspension. The layers are less thick, and the type and dimensions of the cavities and the thickness of the walls are varied depending on the desired qualities of the panels.

Provided are wallboards in which gypsum core is adhered to a paper cover sheet with an adhesive. Wallboards with laminated paper cover sheets in which an inner water-absorbent cover sheet is adhered to the outer paper cover sheet are provided as well. Methods for making these wallboards are provided as well.

The present invention relates to stretched polyolefin fibers comprising a polymer comprising at least one polymeric modifier selected from olefinic polymers modified with an acid and/or an acid anhydride, the use of these fibers in the reinforcement of cementitious compositions, and cementitious composition containing these fibers.

A composition, utility material, and method of making a utility material is disclosed. A composition having an improved setting time may include a plurality of microparticles mixed with a sodium silicate binder and an isocyanate setting agent, where the microparticle composition has a setting time of less than or equal to one hour. A utility material may be a wallboard that includes the composition.

A fire proof compound is provided including MgSO4.7H2O) (Mg4Si6O15(OH)2.6H2O) CaO (s)+H.sub.2O (1)⇄Ca(OH).sub.2 (ΔH.sub.r=−63.7 kJ/mol of CaO) (CaSO.sub.4.2H2O) H.sub.4 Mg.sub.2 Si.sub.3 O.sub.10). The compound can be added to a gypsum substrate of a wallboard to manufacture a fire proof wallboard. The compound can also be mixed with a paint to provide a fire proof paint. In certain composition, the compound can also exhibit an electromagnetic field blocking property. An existing wallboard manufacturing process line can be modified to accept the additional process of adding the compound to the gypsum substrate of the wallboard.

Gypsum based compositions, processes for making same, and articles made therefrom. In one example, the gypsum based composition can include about 1.5 wt % to about 3 wt % of a starch, about 11 wt % to about 14 wt % of a paper, about 0.7 wt % to about 2.3 wt % of vermiculite, about 1.3 wt % to about 3 wt % of a plurality of reinforcing fibers, about 7 wt % to about 10 wt % of a binding agent, about 2 wt % to about 4 wt % of perlite, and about 65 wt % to about 75 wt % of a calcium sulfate, where all weight percent values are based on a combined weight of the starch, paper, vermiculite, plurality of reinforcing fibers, binding agent, perlite, and calcium sulfate.

A plaster-based material, in particular a plasterboard intended for the interior fitting of dwellings, contains a metal complex of EDTA. The plaster-based material is used for reducing the amount of volatile organic compounds present in the atmosphere inside dwellings, offices or public buildings.

The present disclosure relates more particularly to calcium sulfate-based slurries useful, for example, in making gypsum boards for building construction, as well as methods for using them, e.g., to make gypsum boards, in one aspect, the present disclosure provides a calcium sulfate slurry composition comprising calcium sulfate present substantially in the form of one or more hydrates, the calcium sulfate being present in an amount in the range of 70-99.8 wt % on a dry basis, calculated as stucco; and a cationic starch present in an amount of 0.10-10 wt % of the amount of calcium sulfate as stucco on a dry basis, the cationic starch being substituted with amine and/or ammonium groups and having a % N value in the range of 0.10 wt. % to 2 wt %, and an RVA viscosity value of at least 100 cP at 65° C. and 16 wt %; and water, in an amount sufficient to form a slurry. The disclosure also provides gypsum-based materials useful as building materials, e.g., for use as building boards in construction of walls and ceilings of buildings.

A waterproofed gypsum board and associated method are provided, featuring the use of a mixture of magnesium oxide and a gypsum crystal modifier for improving the resistance to sagging of the waterproofed gypsum board, in particular, in moist and warm climatic conditions.