摘要:
This invention relates to a process for the preparation of polyarylene sulphides, preferably polyphenylene sulphide (PPS), whose fusion viscosities can be adjusted to specified values, from alkali metal sulphides and polyhalogenated aromatic compounds in a polar solvent in the presence of a ketone or pinacone. The resulting polyarylene sulphides which have specified fusion viscosities are distinguished by high stability of the melt and low chlorine content. They cause little corrosion in the reaction vessels used for their preparation.
摘要:
Extrusion impregnating device for continuous production of unidirectionally fibre-reinforced polymer mouldings with fibre contents between 50 and 70 vol-%, which makes it possible to produce linear profiles with circular, oval or rectangular cross-sections while at the same time enabling high-quality impregnation and the attainment of excellent mechanical characteristics.
摘要:
The invention relates to mixtures of poly(arylene sulphides), glass fibres and maleamidic acids, which are remarkable for good mechanical properties and an increased melt viscosity of the matrix resin.
摘要:
Nitrocellulose/polyester or alkyd resin dispersions having a high pot life and low requirement for coalescing agent may be prepared with the aid of water-insoluble aminoplast resins if care is taken to ensure that a mixture of these components is present within the particles of the disperse phase.
摘要:
Aqueous emulsions of unsaturated polyester resins comprising two "air-drying" polyesters, one polyester containing co-condensed polyalkylene glycol residues and the other polyester being free from groups such as these, can be hardened uniformly and relatively quickly to form tack-free, open-pore coatings, even on exotic woods.
摘要:
Octa-2,7-dienyl-1-amine and octa-1,7-dienyl-3-amine, from which octyl-1-amine can be prepared, are prepared selectively by telomerizing butadiene and ammonia in a two-phase system, the catalyst being used in an aqueous phase and an organic medium which is immiscible or only slightly miscible with water being employed as the second phase.
摘要:
Chlorinated aromatic compounds are dechlorinated in a simple and inexpensive manner by heating them to 300.degree. to 450.degree. C. in a salt melt in the presence of water and/or water vapor and carbon.
摘要:
Organic compounds of reduced sulphur content and sulphur-free organic compounds can be prepared from organic mercapto and/or disulphide compounds in a particularly advantageous manner by hydrogenolytic elimination of hydrogen sulphide if the elimination of hydrogen sulphide is carried out in the presence of an organic solvent by means of an aqueous, non-oxidizing, strong acid and elemental iron, aluminium and/or zinc in the presence of catalytic amounts of nickel and/or cobalt.