摘要:
In the hydrogenation of polymers or copolymers synthesized from dienes, or containing diene hydrocarbons, which is as a rule carried out in an organic solvent using hydrogen in the presence of conventional complex hydrogenation catalysts based on metals of sub-group 8 of the periodic table of the elements and aluminum trialkyls it is important to have from 0.5 to 50 moles of water present in the hydrogenation zone per mole of the heavy metal component of the catalyst. The hydrogenation time can be substantially reduced by this measure.
摘要:
A process for the manufacture of urethane group containing polyisocyanurate foams produced by mixing polyisocyanates and polyols and (if required) frothing agents, auxiliaries and additives in the presence of a co-catalyst system which consists of a 1,3,5-tris(N,N-dialkylaminoalkyl)-s-hexahydrotriazine and an organic mono- or polycarboxylic acid, a polyesterol with an acid number greater than 4 or a mono-ester of polycarboxylic acid.
摘要:
A process for the manufacture of block or graft copolymers of polyalkylene oxides and vinylaromatic polymers or diene polymers. The block or graft copolymers are manufactured by reacting vinylaromatic polymers or diene polymers bearing methyl methacrylate end groups with polyalkylene oxides bearing alkali metal alcoholate end groups. The block or graft copolymers may be used as antistatic agents for plastics, as coating materials for non-woven webs, as intermediates in the manufacture of polyurethanes and as surfactants, protective colloids or emulsifiers.
摘要:
A layer of electrically conductive polymers is applied by a process in which carbon fibers of filaments or sheet-like structures of carbon fibers or filaments are coated with sulfonic acids of phthalocyanines or porphyrins, the filaments treated in this manner are made the anode in a solution which contains monomers from the class consisting of the 5-membered heterocycles, and the monomers are anodically polymerized so that a conductive layer is formed on the fibers, filaments or sheet-like structures.
摘要:
A process for the manufacture of high impact and translucent polystyrene, in which, in a first stage, styrene is prepolymerized in mass or in solution in the presence of a rubber, and the polymerization is then completed in mass, in solution or in aqueous suspension. The prepolymerization is taken to a stage where the amount of styrene converted is from 3 to 10 times the amount of the elastomer constituent of the rubber, and at this conversion the disperse soft-component phase formed should have a mean particle size of less than 1 .mu.m and should contain from 35 to 65% by weight of free or chemically bonded polystyrene segments. The translucent styrene polymers of high impact strength may be used for packaging purposes.
摘要:
Impact-resistant thermoplastic molding materials prepared from a rigid component and a soft component. The rigid component consists of polystyrene, the soft component consists of a mixture of a polyolefin with a copolymer of a vinylaromatic and a diene hydrocarbon which has been prepared by anionic solution polymerization and which may have been hydrogenated. The molding materials may be used for the production of molded parts for use in domestic appliances, automobiles and refrigerators.
摘要:
This invention relates to a process for the manufacture of graft copolymers based on methyl methacrylate polymers. The methyl methacrylate polymer is reacted with a high molecular weight organic compound containing at least one alkylene oxide unit having an alkali metal alcoholate end group, during which reaction transesterification occurs to eliminate alkali metal methoxide and cause chain joining. The graft copolymers may be used for the production of shaped articles or coating compositions and as additives, antistatic agents or adhesion promoters for plastics materials.
摘要:
Modified copolymers of vinyl aromatic compounds or diene hydrocarbons with diisopropenylbenzene. They contain at least 0.2% of polymerized units of a group of the general formulaThe copolymers are intermediates in the manufacture of block copolymers and graft copolymers suitable for use as impact-resistant plastics or polymeric antistatic agents.
摘要:
The invention relates to a process for separating tenaciously elastic materials such as plastics and rubber from materials tearing and/or defiberizing under high mechanical stress, particularly paper, and to a device for performing said process. The process is characterized in that the mixture of materials to be separated is subjected to high radial, axial and tangential acceleration forces, whereby a mass flow of shredded fibrous material and a mass flow of substantially unshredded plastics is withdrawn separately. The device for performing the process consists of a screen basket which is cylindrical or preferably polygonal in shape and has borings in its jacket to let the defiberized material pass through, a rotatable driving shaft being arranged coaxially inside the screen basket, with blades being attached to said driving shaft, preferably in rigid connection.
摘要:
A process for hydrolyzing alkyl monohalides comprises using activated carbon impregnated with alkali metal hydroxide or alkaline earth metal hydroxide in the presence of water and converting the alkyl monohalides virtually quantitatively into the corresponding alcohols. Apparatus for carrying out the process comprises at least one, preferably two, especially three, reactors (2), especially tubular reactors. The process is also particularly useful for preparing alcohols.