摘要:
Thermoplastic polyurethaneurea elastomers prepared from organic polyisocyanates (A) and a mixture (B) containing Zerewitinoff active hydrogen atoms are disclosed. The mixture (B) is prepared from 1) 40 to 85 equivalent-% (relative to isocyanate groups in (A)) of one or more compounds having an average of at least 1.8 Zerewitinoff active hydrogen atoms and a number average molecular weight of 400 to 10,000, 2) 10 to 60 equivalent-% (relative to isocyanate groups in (A)) of water and 3) 0 to 45 equivalent-% (relative to isocyanate groups in (A)) of one or more chain extenders having an average of at least 1.8 Zerewitinoff active hydrogen atoms and a molecular weight of 62 to 400. The preparation process comprise mixing (A) and (B) in a static mixer under conditions in which no reaction occurs between (A) and (B), and reacting the mixture in a second static mixer. The resulting polyurethaneurea elastomer is useful for the production of moldings.
摘要:
A process for the production of thermoplastic polyurethane elastomer is disclosed. The process entails (a) introducing and homogeneously mixing in a first static mixer (A) an isocyanate and (B) a mixture of compounds having an average of 1.8 to 3.0 Zerewitinoff active hydrogen atoms having a molecular weight of 400 to 10000 with and chain extenders having an average of 1.8 to 3.0 Zerewitinoff active hydrogen atoms and a molecular weight of 62 to 400 and optional auxiliaries to form a substantially unreacted mixture and (b) reacting said substantially unreacted mixture in a second static mixer to form thermoplastic polyurethane elastomer. The elastomer thus produced has improved mechanical properties and is suitable for the production of moldings.
摘要:
The present invention relates to a continuous process for the production of impact resistance-modified thermoplastics. An elastomer, in particular a particulate graft polymer with a water moisture content of 1 to 50%, preferably 10 to 40%, is incorporated into a thermoplastics melt in a large volume kneader reactor. The mixing ratio of elastomer to thermoplastics melt is 4:1 to 1:4. The energy required to melt the elastomer and to evaporate the adhering water is added by heating the walls of the apparatus and via the kneading action of the installed rotating parts.
摘要:
The present invention relates to a continuous process for the production of impact resistance-modified thermoplastics. An elastomer, in particular a particulate graft polymer with a water moisture content of 1 to 50%, preferably 10 to 40%, is incorporated into a thermoplastics melt in a large volume kneader reactor. The mixing ratio of elastomer to thermoplastics melt is 4:1 to 1:4. The energy required to melt the elastomer and to evaporate the adhering water is added by heating the walls of the apparatus and via the kneading action of the installed rotating parts.
摘要:
The invention relates to disc reactors with a large free usable volume which are kinematically self-cleaning, consisting of two or more parallel counterrotating shafts, on which toothed discs with scrapers, which are distributed over their circumference, are disposed, and a surrounding housing. The toothed discs are arranged perpendicularly to the axes of rotation in planes which are echeloned one behind the other such that they mesh with one another.
摘要:
The discharge apparatus comprises an at least four-shaft screw pump having engaging shafts (1,2,3,4) which rotate in opposite directions in pairs. The viscous product to be processed is caught up over a large area and removed by the screws. A double shaft screw pump is connected downstream of the actual collection zone as a pressure build-up zone. The two center screws (2, 3) of the collection zone merge equiaxially into the screw shafts (2a, 3a) of the pressure build-up zone. The collection zone and the pressure build-up zone are combined into one constructional unit. At least one screw shaft is driven. The resulting high viscosity product strands (7) are caught up by the screws in the collection zone and are moved on into the pressure build-up zone. The double shaft screw pump is used for the build up of a high operational pressure and thus provides the prerequisite for the subsequent connection of further procedural stages. The universal possibilities of use of this discharge apparatus are to be stressed in particular.
摘要:
Differences in the rates of flow of media flowing through vessels are equalized by a mixer which consists of a basket-like rotating framework slightly smaller in external diameter than the internal diameter of the tubular vessel, and which comprises a central, stationary column.
摘要:
The invention relates to a fully self-cleaning reactor/mixer having a large freely usable volume, that cleans itself kinematically, consisting of two or more parallel shafts (2, 2') rotating in opposite directions, on which are located spirally arranged, axially offset paddles (3, 3') with scrapers (4, 4', 5, 5') on the front and rear of the paddles, and a surrounding housing (1). Since all the scrapers (4, 4') on the upstream side of the paddles (3, 3') convey the material concerned outwards and all the scrapers (5, 5') on the downstream side of the paddles convey the material inwards, axial conveyance is obtained.
摘要:
A recording medium with a multicolor high resolution pattern created by layer packs. Pattern-forming layers of the layer packs are successively applied by photolithographic means in a sequence corresponding to a color of the high resolution pattern. The pattern-forming layers of the layer packs are separate from one another on the substrate of the recording medium.The process for producing the recording medium includes applying a photoresist layer to a substrate and developing the photoresist. Pattern-forming layers are successively applied over the whole surface of the substrate in a sequence corresponding to a color. The remaining photoresist and the layers overlying it are removed to leave a sequence of pattern-forming layers on the substrate separate from any adjacent pattern-forming layers.
摘要:
An apparatus for melt-spraying thermally sensitive material of low viscosity comprises a heatable multi-screw extruder having intermeshing, self-cleaning screws of specified clearance between the screws and between the screws and the extruder housing, a heatable pump for delivering molten material from the extruder to a heatable atomizer and a spray tank in which the atomizer is located for cooling and solidifying the melt-sprayed material.