Abstract:
PROBLEM TO BE SOLVED: To provide a mixing kneader having manufacture standard provided with a mechanical stable shaft with respect to generated high shearing force.SOLUTION: The mixing kneader is provided with at least two shafts 2, 3 and a kneading rod 4 is arranged on a web 5 in the surface of the shafts and the shafts are surrounded by the housing 6. In the housing 6, at least one opening 10 is formed on the shaft and at least one opening 11 for discharging a product is formed, the shafts 2, 3 are supported in both end parts, at least one end part is driven and the structure of the shaft is constituted so that the a value obtained by multiplying 100 to a value obtained by dividing the difference between the absolute value of bending natural frequency and exciting object frequency by the bending natural frequency may become 5.
Abstract:
PROBLEM TO BE SOLVED: To provide a method for continuously producing particulate crosslinked gelatinous polymers by copolymerizing water-soluble monoethylenically unsaturated monomers (a) with 0.001 to 5 mol% (based on the monomer (a)) of monomers (b) containing at least two polymerizable groups in a kneader. SOLUTION: The method for producing particulate crosslinked gelatinous polymers is characterized in that at least one of following conditions is satisfied: (1) the degree of charging of the monomers in the kneader is at least 71%; (2) the water-soluble monoethylenically unsaturated monomers contain hydroquinone hemi-ether up to 150 ppm; (3) the polymerization zone temperature is higher than 65°C; and (4) the kneader has back mixing ratio less than 0.33. Further, a material added to an inlet of the kneader is conveyed to an end part of the kneader in the axial direction. COPYRIGHT: (C)2010,JPO&INPIT
Abstract:
The invention relates to a method for producing water-absorbing polymer particles, wherein an aqueous polymer gel is applied to the conveyor belt of a circulating air belt dryer by means of a slewing belt conveyor, and the slewing belt conveyor is accelerated starting from an end position over a first slew angle to an angular velocity v1, decelerated over a second slew angle to an angular velocity v2, and decelerated to the other end position over a third slew angle.
Abstract:
Mixing kneader comprises at least two shafts (2, 3) that bear kneading bars (5) on crosspieces (4), can rotate in bearings at both ends, are driven from at least one end and are surrounded by a housing (6) that has top openings (10) above the shafts and a product discharge opening (11). The mixing kneader has at least one of four defined features, e.g. the natural bending frequencies of the shafts differ from the excitation frequencies by at least 5%. Mixing kneader comprises at least two shafts (2, 3) that bear kneading bars (5) on crosspieces (4), can rotate in bearings at both ends, are driven from at least one end and are surrounded by a housing (6) that has top openings (10) above the shafts and a product discharge opening (11). The mixing kneader has at least one of the following features: the natural bending frequencies of the shafts differ from the excitation frequencies by at least 5%; at least one shaft is a hollow shaft through which a temperature-controlling medium flows from an inlet (12) to an outlet (13); at least one top opening is closed by a displacer and the gap between the displacer and the kneading bars is no greater than that between the kneading bars and the housing; the cross-section of the product discharge opening is adjustable. An independent claim is also included for a process for producing poly(meth)acrylates using a mixing kneader as above.
Abstract:
The invention relates to a method for producing water-absorbing polymer particles, comprising the addition of a solid additive to a polymer gel by means of a feed screw (1), wherein the solid additive and a gas volume flow are fed into the feed screw (1) by means of an inlet channel (2).
Abstract:
In the continuous preparation of finely divided, gel-form, crosslinked polymers (I) by copolymerizing water-soluble mono-ethylenically unsaturated monomers (II) with 0.001-5 mol. % (based on (II)) of monomers (III) containing at least two polymerizable groups in a kneader through which materials are transported axially, (a) the degree of filling of the kneader is at least 71%, (b) (II) contains up to 150 ppm hydroquinone hemi-ether (IV), (c) the polymerization zone temperature is more than 65[deg]C and/or (d) the kneader has back mixing ratio less than 0.33.
Abstract:
A process for producing water-absorbing polymer particles, comprising the addition of a solid additive to a polymer gel by means of a conveying screw (1), wherein the solid additive and a gas volume flow are fed to the conveying screw (1) by means of an addition channel (2).
Abstract:
The invention relates to the use of an apparatus for adding at least one solid or viscous liquid additive, or an additive dispersed in solvent, to a reactor interior of a reactor for preparing crosslinked, finely divided polymers by copolymerizing (a) water-soluble, monoethylenically unsaturated monomers and (b) from 0.001 to 5 mol %, based on the monomers (a), of monomers comprising at least two polymerizable groups, (c) from 0 to 20 mol %, based on the monomers (a), of water-insoluble monoethylenically unsaturated monomers, where the apparatus comprises at least one screw for conveying the at least one additive and the at least one screw ends in an addition orifice substantially flush with the inner wall of the reactor interior.