DE1912302B2 - SEPARATION DEVICE AND METHOD FOR MOLTEN POLYMERS - Google Patents

Description

such channel or means is equipped and so flows in 25 of the inner surface of the pipe and in the

Relative to the surface of the polymer melt cross section represents a ring, while the steam

is arranged. that a free fall of polymers at a much greater linear velocity than that

through the gas between the outlet and the polyamide flows along the center. It was

Polymer melt is largely prevented. found that it is possible to melt the

3. The method according to claim 2, characterized by separating the polyamide from the steam in said pipe, draws that the polymer is a polyamide, which is in the end of the tube an opening that together with steam or nitrogen or, for example, above the melt of the melt both flows. spinning device is arranged, such a shape is provided that the polyamide along the wall

35 flows down the pipe and falls into the melt, during the

Steam flows out from the center of said opening and then turns upwards and through one

The invention relates to a new and suitable outlet being drained. The pipe is

improved device for use with the commonly extended, the extension being a

continuous production of high molecular weight 40 certain stretch before its Endi begins to the

Polymers and especially of fiber-forming poly- lower the speed of the steam when it

ineren. In particular, it relates to a sewing at the pipe outlet. For example, a

Separators for currents flowing in a pipe from such a device consist of a vertical pipe,

molten fiber-forming polyamide and steam. that ends in a vertical cone that extends above the

Although the invention is arranged with reference to 45 melt lake. The polymer flows the

Polyamides and steam are described, but they can fall down the inner wall of the cone and trickle off

of course also on streams flowing in a pipe open large end of the cone into the melt,

»Other liquids and gases and vapors are used while the steam is at a reduced speed

which has similar physical properties as digkeit leaves the wide, open lower end of the cone

Have molten polyamides and steam and move 50 and back up from the melt and

Behave in a similar manner For example, flowing through a suitable exhaust device,

lias gas or vapor consist of nitrogen. According to the application it has now been found that

In the manufacture of polyamides by a polymer, the polymer tends to form stalactites, which are dated

continuous process in which a pipe is hanging down the pipe or cone end, the

Is used, it happens not infrequently that high-molecular stalactites are thermally broken down,

kular polyamide in molten form together pieces of this degraded material can be put into the

is obtained with steam and that it is necessary to fall the latter melt and to catalytic gelation

to separate from the polyamide when they give rise to the polymer tube, whereby, for example, the

come out. The steam from moist extruded film can be of poor quality. the

that originally in the monomer out- 60 Catalytic gelation can also be new polymer

Gangsmaierialien was contained, or he can in the record, the about such degraded polymer stalactites

Polymerization reaction has been chemically developed flowing. The same disadvantage arises, of course, with

his or, as a non-oxidizing gaseous medium, other forms of objects emerging from the

have been introduced. It should be noted that polymers of the melt are produced,

the steam from the pipe usually with a high 65 The subject of the invention is a separation device

Speed exits. It is possible to use the polyamide device for molten polymers that work together with

and the steam in a heated vented container, steam or other gas or steam in

such as B. the melting chamber of a melt spinning before a line of a continuous polymerization

device flow, which is characterized in that the separation device has a widening outlet for said conduit, the said outlet has such a shape and m-t such a channel or Mutel is equipped that a Free fall of polymers through the gas between the outlet and the polymer melt to a large extent is prevented

The invention is also a method in which molten polymers, together with steam or other gas or steam in a line of a continuous polymerizer flow, are passed through a separation device, which is characterized is that the separation device has a widening outlet for the said line, said outlet having such a shape and being equipped with such a channel or means and so with respect to the surface of the Polymerert melt is arranged that a free fall of polymers through the gas between the outlet and the polymer clay is largely prevented.

The severing device can be made of any suitable material and can with the aid of a conventional device, such as. B. with the help of a jacket, which is made electrically or by steam Diphenyl or diphenyl oxide is heated to a temperature above the melting point of the polymer, such as B. nylon-66 are held.

The following is an exemplary embodiment the device according to the invention described.

In the drawings show:

F i g. 1 is a schematic cross-section of a prior art severing device, which has a simple conical outlet above a melt,

2 shows a schematic cross section of a severing device with an obliquely cut off conical outlet,

3 shows a schematic cross section of the lower edge of the conical part of a device according to the invention Disconnection device,

Fig. 4 is a cross-sectional view along the line 1V-1V of Fig. 3 and

F i (j,. 5 a cross-section on the line V-V of FIG. 4.

In order to avoid the formation of stalactites, there must be a free fall of polymers from the end of the Pipe exit into the melt can be avoided. When the cone of Fig. 4 at the end of the tube 2, as in F i g. 1 explained, is simply lowered so that its lower edge touches the melt 6, then the Steam 8 does not escape freely. This difficulty can be overcome to some extent by part of the cone, as in Γ i g. 2 is cut off. However, it has been found in practice that the highly viscous polymers 7 do not run on the edge of the cone to point 16, which is immersed in the melt, but also partly drips off the said edge in a free fall.

This difficulty can be eliminated in that a downward sloping lower edge of the conical structure is provided, wherein the edge is curved upwards, so that a channel 10 is formed, as shown in FIG. 3 is shown.

The channel is of a suitable size and dimensions to accommodate the polymer throughput so that the polymer flows down the channel and into the melt without the the above-mentioned undesirable free fall occurs. Both -Jie hatchets and the depth of the canal take off starting from a maximum at point V (see FIG. 3) at which the lower edge of the conical structure is closest to the apex, because the polymer is on this Point tends to accumulate. Preferably, but this is not essential, the accumulation can continue be reduced by providing the inside of the conical structure with a rib 12, facing inward and having a width that increases towards the base at point V, as shown in FIG Fig. 4 is shown. It has been found advantageous to give the cross-section of said rib approximately the shape shown in Figure 5, i.e. e., she with two To provide channels 14 along which the molten polymer can flow to free waste from the Prevent rib itself.

It is clear that one skilled in the art can make various changes in shape and size the separation device according to the invention can make that fall within the scope of the present invention fall as long as a free fall of the polymer is prevented by the gas into the polymer melt.

For this purpose 2 sheets of drawings

Claims (2)

ι L. direction, with the molten polyamide collecting at the bottom of the container to be drawn off as required, during which the 1. Separator for molten polymer vapor escapes through a vent. In practice, re which is, together with water vapor or a 5, however, due to the speed, mn of the outlet of the other gas or steam in a conduit of a vapor from the open end of the tubes, a part of continuous polymerization flie- the polyamide unavoidable on the walls des Ben, characterized in that the container is sprayed, which is therefore covered with a film separating device over an expanding area. It would be expected that this occurs for the named line, the polyamide film, which has a temperature above its named outlet and has such a shape and has a melting point, continuously downward into such a channel or means that polyamide melts was run, but at least a free fall of the polymer through the gas part remains hanging for a sufficient time so that an undesirable degradation of the polyamide occurs between the exit and the polymer melt
is largely prevented. 15 Various devices in the form of 2. Process in which molten polymer-modified ends for the pipe are developed, whereby re, which together with water vapor or one but not a satisfactory solution to the problem of other gas or steam in a line one of the separation of the effluent into steam on the one hand and in continuous polymerization device On the other hand, a steadily flowing stream of polyamide flows ben, passed through a separation device 20 was achieved. are characterized in that the separating The present invention is based on the fact device an expanding outlet for that the polyamide and the steam through the tube in said conduit, said conduit moving in an annular two-phase flow, d. i.e. that Exit has such a shape and along with a rather viscous molten polyamide