Flexible resilient flame-retardant and intumescent polyurethane foam is prepared from a reaction mixture comprising a polyether polyol, an organic polyisocyanate, a blowing agent, a surfactant, a catalyst, a flame-retardant and hydrated alumina; the amount of flame-retardant is 30 to 160 parts by weight/100 parts of the polyol. Preferably, the mixture also comprises a low-viscosity linear polyeste...

The disclosure relates to a storable polyol pre-mixture for making flame-retardant polyurethane foam plastics consisting of a mixture of a polyester polyol or polyether polyol and an ammonium polyphosphate as a flame-retardant agent. The pre-mixture contains more particularly an ammonium polyphosphate which corresponds to the general formula (I) H(n-m)+2(NH4)mPnO3n+1 (I) in which n stands for an i...

Polyurethane foams prepared with halogenated phosphoric acid flame retardant have low scorch and surface discoloration when prepared in the presence of a composition containing phenothiazine, 4,4'-thio-bis-(6-tertiary butyl meta cresol), and organophosphite.

The invention concerns a process and an apparatus for making a stable solution or dispersion of a hydrosoluble powder. It is characterized by the simultaneous use of a system for withdrawing powder from a vessel (2) e.g. by means of a gas (4), the dilution of the powder in a carrying gas, the driving with said carrying gas, of the obtained dilution, through a transfer duct (10), the passage of the...

The present invention relates to an enclosure member consisting essentially of solid, non-aromatic polymers that have a linear carbon to carbon backbone structure and have a plurality of free hydrogen atoms attached to the carbon atoms with a permeability to wet and dry solvents and fuels of less than 1/50, of the permeability of untreated enclosure members having a thickness of 1 mm, a portion of...

The present invention relates to a process for making polystyrene pellets, and more particularly for making expandable polystyrene beads, by forming a styrene polymer melt and extruding such through a die to form continuous strands thereof. After exiting the die but prior to substantial cooling, the strands are cut into pellets. Such plano-convex pellets are optionally screened to remove undesirab...

PCT No. PCT/CH85/00011 Sec. 371 Date Sep. 26, 1985 Sec. 102(e) Date Sep. 26, 1985 PCT Filed Jan. 24, 1985 PCT Pub. No. WO85/03465 PCT Pub. Date Aug. 15, 1985.A powdery material is prepared by atomization from a molten alloy having the following composition in weight percent: chromium: 10-30; aluminium: 1-25; carbon: less than 0.5; nickel: less than 10; iron: the balance, with a cooling speed at le...

Orthogonal indicia of orientation of a drilling tool 22 at the end of a drill string 18 within a borehole 12 are measured by a pair of sensors at intervals of a first frequency. Pressure pulses indicative of the tool face angle are generated in the mud flow passing along the drill string 18 by means of a mud flow valve in response to each measurement, and the pressure pulses are sensed at the surf...

Novel methods and composition are provided for the making of foamed, crosslinked polyethylene utilizing cyclic peroxyketal crosslinking/blowing agents. The novel compositions include esters of thiodipropionic acid as activators.

A masonry cement is prepared by dry mixing portland cement, diatomaceous earth and a water-swellable colloidal clay, such as bentonite. Accordingly, the crushed limestone and other ingredients previously included in masonry cements for admixture with portland cement can be completely eliminated and substituted by diatomacious earth and water-swellable colloidal clay. In this manner, a combination ...

A flexible film suitable for use in adhesive medical dressings which film comprises a blend of polymers characterized in that the blend comprises a continuous matrix of 1,2 polybutadiene and an incompatible polymer which forms a discrete particulate phase within the continuous matrix and the film contains voids is described.

Fibers prepared by spinning, drawing and drying dilute solutions of ultrahigh molecular weight polyethylene or polypropylene are modified by including in the dilute solution a polymeric additive. The polyethylene fibers so prepared have melting points above 140 DEG C. and exhibit improved adherence to matrices, resistance to fibrillation and other advantageous properties. Additives include lower ...

A process for producing articles of polytetrafluoroethylene (PTFE) is disclosed. The process allows some of the conventional plastic fabrication techniques to be used with PTFE which until now have not been possible. The process comprises the steps of intensively mixing and thermokinetically heating PTFE granules in an enclosed container with a plurality of blades attached to arms rotating about a...

Elastomers reinforced with fibrous composite materials and having improved properties are obtained if the strengthening means used are composite materials based on reinforcing fibres and reactive resins which are coated with adhesion promoters based on polyisocyanates.

Methods of making low density modified polyimide/polyimide-amide foams and the resulting compositions. An N-substituted aliphatic imide is prepared by reacting a suitable aromatic dianhydride with a suitable oxime. A polyimide forming material is prepared by dissolving the N-substituted aliphatic imide in an esterifying solvent, then adding a suitable aromatic diamine. This material is dried to a ...

A display in which electrons are produced from a helium discharge and are drawn through selective holes in a control matrix into a plasma-free chamber, where they absorb energies of several kV, and finally generate light spots on a fluorescent screen, is provided according to the invention as follows. The cathode (8) of the gas discharge consists of zircon, at least on its emission surface; the ga...

Producing a glass solder seal without interfering thermal stresses in a display device containing at least two mutually parallel plates tightly connected at the edges via a frame. One plate is coated with a pattern of separately addressable electrodes which are each brought to the outsides through the frame. The method includes (a) also covering the electrode pattern in the region provided for the...

A structure in the form of a container resistant to corrosive chemical attack is made by mixing in a rotary drum a synthetic plastics resin material with two different hardeners and a filler of particulate siliceous material which may be sand, gravel or quartz particles, casting the material into a mould and coating at least the face exposed to the chemical attack with a skin 47 of the same resin ...