DE1595735A1 - Device for the production of macromolecular synthesis products - Google Patents

Description

Device for the production of macromolecular synthesis products The invention relates to a type of planetary roller extruder comprising a housing with a central shaft and planetary body designed for increased internal pressure Device for continuous polymerization, polycondensation or polyaddition of macromolecular synthesis products from their starting materials.

For the production of macromolecular synthesis products, for example Polystyrene, suspension polymerization is often used, i.e. one works in suspension using appropriate reactors, which has the advantage of a flexible Operation combines with the easy dissipation of heat of reaction, so that the Polymerization within precise thermodynamic parameters, e.g. within a narrow temperature range, can be controlled. On the other hand, must have disadvantages are taken in Kaur, which as here in detail does not need to be explained, in particular related to the processing.

Although the continuous operation, especially the bulk polymerization, has achieved great importance, its universal implementation and control is through Circumstances hindered, especially with the progress of polymerization with insufficient Dissipation of the heat of reaction, sometimes with inadequate adaptation of the thermodynamic Conditions related to the various reaction stages. Often it is because of the Continuity of the procedure the exact separation and adherence to in the process flow thermodynamic conditions that change over time are not possible. - In detail is one of the known measures for continuous polymerization, polycondensation and the like. The continuous polymerization of diolefins takes place z. B. in cylindrical reaction vessels with the help of screw conveyors (British PS 537 7 701, German PS 715 825). The has also been used for a long time Multi-stage polymerization of monostyrene with the interposition of preferably horizontal working reactors in connection with transport screws (British PS 683 329). In Similarly, twin or continuous screw extruders are used Kneader with screw conveyors, the rotary movement of which is a simultaneous axial forward and Backward movement is superimposed on trioxane polymers in a continuous manner or copolymers, with the finished product being discharged if necessary in the solid state Polymerisates (German PS 1 161 421) to produce. The more will also be fine Multiple screw presses for the production of polymerisation and polycondensation products used (German PS 895 o58). - All of these known measures are from the above indicated reasons in need of improvement, the considerable apparatus also interferes Expenditure.

For other purposes, namely for extrusion and injection molding of thermoplastic Plastics, a so-called planetary roller extruder has become known, which is driven with a Central shaft and surrounding planetary bodies is equipped, which is like a planetary gear in the case of angled toothing with the central shaft and, if necessary, the corresponding toothed one Comb the housing (see German PS 1 003 948, DAS 1 177 808), with planetary roller extruder one achieves a considerable improvement of what would otherwise be the case with extruders Plasticizing and mastifying effect - Dooh are the problems of polymerization or polycondensation of macromolecular synthesis products through the existence of planetary roller extruders has not yet been touched.

The invention is based on the object of specifying how the device must be designed with the in a simple manner and, if necessary, under more precise Separation and compliance with thermodynamic changes over time in the course of the process Conditions from known starting materials through continuous polymerization, Polycondensation or, if necessary, also polyaddition, macromolecular synthesis products are produced can be.

The invention relates to a type of planetary roller extruder Made up of a housing with a central shaft and planetary body for increased internal pressure set up device for continuous polymerization, polycondensation or polyaddition of macromolecular synthesis products from their known starting materials. The invention consists in that the central shaft and the planetary body are helical teeth with different slopes in sections and the so defined Sections of the housing zones are assigned different heating and / or cooling are. - Another embodiment of the invention provides that the housing wall Distributed over its length and adapted to the zones, holes for the supply of accelerating and / or catalytically active substances and / or for gas or monomer suction. In addition, it is advantageous in the device according to the invention between to arrange the planetary bodies in a known manner locking rods.

According to the invention, it is assumed that the known planetary roller extruders further developed by the specified design to planetary roller reactors and therefore for polymerization, polycondensation and polyaddition in particular Way are suitable. For feeding the starting materials into the planetary roller reactor special pressure introduction devices are to be provided when the polymerisation, polycondensation or polyaddition takes place under increased pressure.

On the outlet side, the material produced holds in the case of the one according to the invention Planetary roller reactor, as it were, as a seal for the internal pressure at the outlet end an outlet nozzle or outlet throttle is provided for this purpose, which accordingly is adjustable.

In planetary roller reactors according to the invention, the heat transfer is be it on the item to be treated, be it on the treated item on the machine elements very cheap.

The surface of the moving and itself present in the machine volume mutually touching effective masohine parts is large enough to plasticize the to bring the required heat into the mass in just as short a time as it gives you possibly to be withdrawn again, for example for the purpose of solidification at the outlet end. It has also been shown that with planetary roller reactors with a small machine volume high volume outputs can be achieved. The invention is based on the knowledge that the last-mentioned advantages of planetary roller reactors in the course of the polymerization or polycondensation of macromolecular substances to surprising effects to lead, if one known planetary roller extruder by sealing the drive shaft stub has set up for increased internal pressure. The planetary roller reactor is according to the invention divided into zones, with the central shaft and the planetary bodies having helical teeth different slope and the corresponding housing zones individually heated or Can be cooled, so that the thermodynamic conditions and changing over time the changes in state of the chemical reaction taking place are taken into account. For more intensive heat transfer, the central shaft and possibly even the Planetary bodies are cooled. The reverse is also true if necessary heating possible. - The operation of the planetary reactors is simple Way to adapt to the respective circumstances. Particularly intensive mixing the reaction partner can also be achieved by using the planetary roller reactors only partially fills with the reactants.

However, a premix can also be used outside of the planetary roller reactors make.

By dividing the central shaft and the planetary bodies into Zones with helical teeth of different pitch is also a clear one Material transport given in the planetary roller reactor, so that according to the gradients Set different dwell times in the individual zones and thus pressure and temperature can also be selected precisely with regard to the time exposure. One can so also take into account the fact that the viscosity of the material to be treated, z. from the original reaction mixture to the finished polymer, on the way through changes the planetary roller reactor by powers of ten, and the pitch of the toothing vary depending on the viscosity. Otherwise it can be used for pressure build-up be appropriate to make the arrangement so that between the planetary bodies in locking rods are arranged in a known manner, the length of which is selected so that that, as it were, every single planetary body in connection with the Sperratäben and works like a screw pump in interaction with the central shaft and housing. Here, the pumping effect can be adjusted by choosing tolerances that differ in zones influence.

Should a sharp separation of the thermodynamic parameters by zone can also be achieved with regard to the pressure, the invention recommends several planar set roller reactors or central shafts with surrounding planetary bodies with the interconnection of chokes to switch one after the other. The latter can also be done so that the reaction components or the reaction material circulates in one or more of these units before it is fed to the following unit, whereby the continuous operation however, it will be an intermittent one.

Throttle designates pressure-maintaining, but the material transport Permitting locks, which also act as thrust rings for assembly and support the planet body and locking rods can serve.

However, a sufficient separation of different pressure zones is achieved also already by the described different pitch of the helical gearing. If necessary, the housing wall can be distributed over the length in all cases and if necessary adapted to the mentioned zones, bores for the supply of accelerating or catalytically active substances. Propellants for the production of foams can be sprayed in this way. Similar measures can be used for degassing purposes or use to remove unreacted monomer components.

The advantages achieved by the invention are mainly in it see that by the planetary roller reactor designed according to the invention in particular simply continuous polymerization, polycondensation or polyaddition of macromolecular synthesis products, even if a relatively complicated procedure with exact compliance with em process process sequence of changing thermodynamic conditions required is; because due to the different dwell times or conveying speeds in the individual zones due to the different pitches of the helical teeth the pressure that is set in each case, through the zone-wise cooling / heating and by the possibility of further starting materials and / or auxiliary materials in the various The planetary roller reactor according to the invention is to supply zones or to suck off gases or monomers to a large extent adaptable to the chemical process sequence. You can do this by choice the drive speed the central shaft and thus the speed of rotation the planetary body special effects can be achieved, be it for example in relation on heat supply or in relation to heat dissipation, depending on the speed. In addition comes a relatively high performance in relation to the size of the planetary roller reactor according to the invention.

The invention is illustrated below with the aid of examples. In addition 1 shows an axial section through a planetary roller reactor according to the invention, FIG. 2 shows the section A-A through the object according to FIG. 1 and FIG. 3 shows the detail B from the object according to FIG. 1.

The in the F g. 1 to 3 shown corresponds in their device First construction of a known planetary roller extruder. It has a central shaft for this purpose 1 with helical teeth and helical planetary bodies 2, which form the central shaft 1 and in the execution example with a corresponding toothing 3 of the housing 4 comb. The central shaft 1 is driven. The drive is not drawn. In order to be used as a Pianet roller reactor, the drive shaft stub 5 is set up by sealing for increased innon prints. In the exemplary embodiment acts it like that Fig. 3 shows a gland seal 6. -In the planetary roller reactor shown, the polymerization, polycondensation can now or polyaddition of macromolecular substances from their known starting materials be made when these are introduced into the planetary roller reactor. In addition are special pressure introduction devices 7 for the individual in the exemplary embodiment Components provided.

To realize different thermodynamic conditions, or about the planetary roller reactor in its mode of operation by the reaction and around to adapt the viscosity of the reaction product to the powers of ten, the central shaft 1 and the planetary body 2 are zoned over their length with a Helical gearing 8 equipped with different pitch. The individual zones are labeled I to III. The resulting different slope of the oblique distortion 8 defined zones are also housing zones under different heating and / or Associated cooling, including the individual housing zones with special feeds 9 for which heating medium or coolant are equipped.

Fig. 2 shows that between the planetary bodies 2 locking rods 10 can be arranged. This can influence the speed of the reaction.

In the embodiment it is shown that as a result of Schleidlicher Incline and corresponding design of the housing 4 different zones are formed are who in turn adapted to the special reaction conditions can be.

A variant in which several planetary roller reactors are not shown is shown or central shafts 1 with surrounding planetary bodies 2 with the interposition of Chokes 12 are connected in series. In the embodiment described with zone division or with the series connection of several planetary roller reactors there is the possibility indicated in the figures, the housing wall with About the length distributed, the mentioned zones adapted holes 11 for feeding of accelerating or catalytically active substances or for gas or monomer extraction Mistake.

With the device described, inter alia. the following reactions carried out: Example 1 700 g of polymethyl methacrylate in powder form are in 1,500 g of monomeric methyl methaorylate dissolved, half of this viscous, colorless solution or 1,100 g are 15 g of benzoyl peroxide in the form of a 50% paste in dicbutyl phtahalate added. 2.0 g of p-dimethyl toluidine are added to the other half of 1,100 g added. The two solutions are continuously in a ratio of 1 to 1 Mixture fed to the feed device of the planetary roller reactor. The polymerization sets immediately. when mixing the two solutions. The temperature is through external cooling of the housing between 80 and 2000 C. or increased gradually from 800 to 2000 C. The lead time is less than 10 min. - The physical properties of the polymer obtained can be through the addition of other monomers to the methyl methacrylate can be modified. In connection with ethylene glycol dimethacrylate, for example, a harder polymer of low thermoplasticity, and by adding butyl methacrylate or 2- {thylhexyl methacrylate polymers of a softer nature can be produced. Instead of dimethyl-p-toluidine like other accelerators, e.g. Dimethylaniline or p-hydroxymethyl-p-dimethyl-toluylsulfone used in conjunction with benzoyl peroxide. - One made in this way Polymethyl methacrylate is suitable as a casting resin for the dental industry.

Example 2 75 parts by weight of formaldehyde gas produced by cleavage of paraformaldehyde, are converted into a solution of 800 parts by volume of carbon tetrachloride introduced, which contains 0.05 parts by weight of diphenylamine and oil78 parts by weight of tributylamine Contains, the gaseous formaldehyde can in a continuous process means the pressure supply device described introduced into the planetary roller reactor in which the solution of the aforementioned ingredients in carbon tetrachloride, given up by another feed device, is presented, whereupon the polymerization at 250 C immediately sets in and progresses. From the planetary roller extruder a suspension is discharged by filtration with simultaneous recycling of carbon tetrachloride is recycled into the process. A polymer is created of high molecular weight, which is produced at 1900 C in a subsequent planetary roller extrusion unit is carried out.

Other catalysts, e.g. triphenylphosphine, dissolved in pentane, give Polymers with similar properties, they can be fed as described.

Example 3 A polyester produced by esterifying a mixture of diethylene glycol, maleic anhydride and phthalate anhydride, is combined with dialyl phthalate diluted to a concentration of 60%. The viscosity is about 15,000 cop at 250 C. 4 ffi of a 50% fit of benzoyl peroxide in dialeyl phthalate are added to the resin solution or the components in this ratio to the Planetwalson reactor continuously fed. The maximum temperature in the reactor is Maintained at 1800 C by housing cooling or central shaft cooling. On whose Discharge part, a clear sheet of tough texture is extruded immediately, During or immediately after the extrusion, glass fibers or nonwovens may be incorporated be, for example, in such a way that two planetary roller extruder units .extruded Foils over a roller system with a fiber fleece insert merged and thus united, a procedure which has the advantage has that the fiber content is protected by the film on both sides and one improved weather resistance is guaranteed. Instead of plates or the The above-described laminate can optionally also directly pipes, profiles, rods or glass fiber reinforced willow boards can be extruded.

Example 4 A prepolymer is made by reacting 280 parts by weight Tolylene diisocyanate and 1,000 parts by weight of anhydrous POlytetramethylene glycol (Molecular weight 1,000), which thereby obtained polymerization of tetrahydrofuran thereby heating the mixture in an atmosphere of dry nitrogen in a closed vessel at 800 C for 3 - 4 hours until the free isoyanate content is 4.2 ß. The highly viscous prepolymer has a viscosity of 16,000 cp and an approximate molecular weight of 2,000. 1,280 g of the prepolymer are mixed with 60 g 1,4 butyl glycol and fed to the planetary roller reactor, wherein the Temperstur by cooling or heating the housing in stages between 60 to 100 ° C is regulated. This creates a polymer with a Kachuk-like texture, You can be extruded in the form of a film, the tensile strength of which is 70 op / cm2 and whose elongation is 600 ffi.

Expectations:

Claims (3)

Claims: 1. In the manner of a planetary roller extruder from a housing built with central shaft and planetary bodies, furnished for increased internal pressure Device for continuous polymerization, polycondensation or polyaddition of macromolecular synthesis products from their known starting materials, thereby characterized in that the central shaft and the planetary body with helical teeth have different incline in sections and the sections defined in this way Housing zones of different heating and / or cooling are assigned. 2. Apparatus according to claim 1, characterized in that the housing wall Distributed along its length and adapted to the zones, bores for the supply of accelerating and / or catalytically active substances and / or for gas or Has monomer suction. 3. Device according to claims 1 and 2, characterized in that that between the planetary bodies in itself known. Way locking bars arranged are.