JPS61222705A - Separating and drying of chlorinated polyolefin - Google Patents

Abstract

PURPOSE:To speedily obtain chlorinated polyolefin granules with high productivity by a method wherein a vented extruder is employed in order to obtain chlorinated polyolefin by separating from halogenating solvent solution. CONSTITUTION:Carbon tetrachloride solution, which consists in concentrating carbon tetrachloride solution having chlorine-containing chlorinated polyethylene dissolved therein at a concentration tank 14, is supplied through a Moyno screw pump 4 to a single-screw extruder 1. The gas evaporated through a vent, which is brought into vacuum state by a vacuum generating deice 2, is introduced through pipes 8, 9 and 10 to condensers 11, 12 and 13 to be condensed and collected to a recovery tank 3. Dried polymer is discharged through a die in rod form and, after being cut with cutters, made in pellet form.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Industrial Field of Application The present invention relates to polyethylene, poly-10-pyrene, polybutene, natural rubber, synthetic rubber, poly-4-methylpentene-1,
When producing a chlorinated polyolefin by dissolving a typical ethylene vinyl acetate polymer and a polyolefin modified with a carboxyl group, a hydroxyl group, etc. in a halogenated solvent solution and chlorinating it, the reaction solution has a chlorine content of 5 to 60 ml. Separate % of chlorinated polyolefins
It concerns a method of drying.

B. Prior art Among these chlorinated polyolefins, various methods are known for separating and drying chlorinated polyolefins with a chlorine content of 60% by weight or more.
There is a method of forming solid particles by spray drying, as seen in Japanese Patent No. 6310, and a method of solidifying and separating the polymer solution by adding it to boiling water, as shown in Japanese Patent No. 46-45s1. □It is well known that chlorinated polyolefins can be relatively easily separated from solvents using hot water assimilation methods.

Problems to be Solved by the C0 Invention On the other hand, chlorinated polyolefins with a chlorine content of 5 to 601 tS exhibit low-temperature softening properties and are highly adhesive; It is impossible to apply to the substance because it adheres to the substance. US Pat. However, in this method, in the initial stage of drying, the degree of fusion may vary depending on the amount of residual volatile matter in the Kuvolimer, from which the solution drops dropwise from the movable drum. Increased withdrawal/
It is difficult to put it into practical use because stretching is not performed smoothly.

Others: Special Publication No. 39-19230, Special Publication No. 40-1
As seen in Japanese Patent Publication No. 237 and Japanese Patent Publication No. 12386/1986, by adding a poor solvent for chlorinated polyolefin, such as alcohol, to the solution,
There is a method of precipitating and separating the bo-11mer. However, even in these methods, the bo-11mer aggregates and becomes lump-like, making it impossible to granulate it, and furthermore, solvent purification requires a great deal of time and processing costs, and post-processing such as drying is difficult and impractical. do not have.

Also, JP-A-57-47303.57-123201.5
As seen in No. 8-213004, there is a method of separating and drying chlorosulfonated polyolefin (PoI) ethylene) from a carbon tetrachloride solution using an extruder (single-screw or multi-screw type). However, in this method, the concentration equipment is not only expensive, but also the residence time during which the raw material polymer is heated is long, which is likely to cause deterioration. In order to avoid causes of deterioration such as
5-60%) is heated to reflux after the reaction,
Hydrogen chloride and chlorine removed (15 degrees
~45%) K was considered to be processed in an extruder.

On the other hand, the present inventor has previously developed a method for solidifying and separating chlorinated polyolefin with a chlorine content of 5 to 5oH1% by a dry spinning method, as shown in JP-A-59-112020 and JP-A-112-021, and a patent application filed in JP-A-59-112,021. In No. 94282, he devised a method for separating and drying internally plastic chlorinated polyolefin with a chlorine content of 50 to 60% by weight using a centrifugal thin film evaporator.

However, since chlorinated polyolefins have different physical properties such as raw material resin, softening temperature, and tensile strength, these methods are applied as a common separation and drying method for chlorinated polyolefins with a chlorine content of 5 to 60% by weight. That is difficult.

As a result of intensive study to solve these problems, we found that chlorine content of 5 to 60%, which has low softening temperature and strong adhesiveness, etc.
We have invented a rapid and highly productive separation and drying method that can easily granulate chlorinated polyolefins present in a wide range of weight percentages.

Means for Solving Problem D2 That is, the present invention uses a vented extruder when dissolving and separating chlorinated polyolefin with a chlorine content of 5 to 60% from a halogenated solvent solution. The present invention provides a method for separating and drying chlorinated polyolefin, which is characterized in that the polyolefin is dissolved in a halogenated solvent and the chlorine content is 5. When producing chlorinated polyolefin by chlorination with ~6o weight S1, after the reaction is completed, the produced polymer is separated from the reaction solution.
This is a method for separating and drying chlorinated polyolefin in which the reaction solution is supplied to a vented extruder equipped with 2 to 4 vents under reduced pressure in the drying step and dried.

As the halogenated solvent, for example, carbon tetrachloride chloroform, chlorobenzene, etc. are used.

CO action The vented extruder used in the present invention is equipped with a heating device whose temperature can be adjusted from the outside of the cylinder, and 2 to 4 vents under reduced pressure to evaporate the solvent, and is capable of extruding the debathing agent and polymer. This equipment simultaneously separates and dries the chlorinated polyolefin from the halogenated solvent solution. As for the type of extruder, a multi-screw type extruder such as an axle-shaft, two-shaft, or four-shaft extruder can be applied. A shaft type extruder is preferred. Of course, the present invention can be applied to single-axis or double-axis
The extruder is not limited to a multi-screw extruder such as a four-screw extruder.

As a specific example of these vented extruders, a single screw extruder is
There are Toshiba Machine's SE (product name), ■Japan Steel Works' P (product name), etc. For twin screw extruders, ■Toshiba Machine's TEM (product name), ■Japan Steel Works' TEX (product name), and Welne.
There is ZSR (trade name) manufactured by Y Company.The shape of the shaft is generally spiral, but the shape of the shaft of the two twin screw extruders is not only spiral, but also the shape of the shaft for mixing in the cylinder 11, Various types of discs, seal rings, rotors, etc. can be combined for the purpose of crosstalk, heat generation enhancement due to mechanical bending, sealing performance, etc.It is sufficient to have two or more vents for removing evaporated solvent, but preferably. The solvent that evaporates from these vents is condensed and recovered in a condenser.

The pressure in each vent zone may be normal pressure or reduced pressure, but in order to improve dryness, the pressure should be 5 OsmHg.
Aba, ~400 wHg aba, is desirable, and as an example, 400 mHg from the stock solution supply side.
aba, 170mHg aba, 9 Os
mHgabs, etc., but are not limited to this combination.

In order to further improve drying performance, the vacuum should be higher toward the extruder exit2, and the final vent zone should be 50 snu
It is also important to manage so that the following conditions are met.

Heating a part of the cylinder of an extruder with a vent Generally, electric heating, steam heating, hot water heating, etc. are used. This heating device is divided into several blocks and the temperature is adjusted for each block. On the raw solution supply side with low BoImer concentration, the temperature is 100 to 170℃, and the solvent evaporates and BoI
On the discharge side, where the 1mer concentration is high, it is important to adjust the temperature to a range of 70 to 100° C. in order to prevent quality deterioration due to thermal deterioration of the 11mer. The temperature of the cylinder is 100
It is difficult to efficiently evaporate the nitrous agent at temperatures below ℃.
Moreover, at temperatures above 170° C., thermal deterioration occurs due to overheating of Bo IImer. Preferably it is 80-160°C. The solvent-degassed Bolmer is discharged from several holes in the die in the form of a rod or a plate with a rectangular cross section, and is delivered to the cutter in pieces at 4°F. The present invention will be specifically explained using an example based on FIG. 2, but the present invention is not limited to this example.

[Example-1] A carbon tetrachloride solution in which chlorinated bo-11 ethylene with a chlorine content of 52.5% by weight was dissolved was concentrated to a polymer concentration of 38.0% by weight in a concentration tank [Co., Ltd.]. The liquid was supplied via Mono pump 0 at a rate of 20 Kt to a single-screw extruder (2) with a shaft diameter of 40φ shown in FIG. At this time, the shaft rotation speed was 105 R/M, the shape of the shaft was spiral, and it was heated by an electric heater that was divided into 5 blocks from the outside of cylinder II, and each block was heated by Ct.

If Cs is Cs, then each temperature is C
1 is 120℃, Cm, Cs is 128℃, C4 is 110℃
, C1 is adjusted to 90°C. The vent zone is in a reduced pressure state by the vacuum generator ■, and the degree of pressure reduction is such that 40 OswiJ (g) is applied from the stock solution supply side.
abs, , Vs is 170 waHg abs,
, Adjust the valve so that Vs is 90■Hg aba
Adjust with ■■. The evaporated gas through this vent is introduced into the condenser ■@@@ which is connected with the pipe ■■・, where the gas is condensed and collected in the recovery tank ■.

The dried polymer II is discharged from a die in the form of a rod and passed through a cutter to form pellets.

The residual solvent in this dried Bomer II was 0.90% by weight, which is good in terms of quality. The operating conditions and results at this time are shown in Table-1.

[Examples 2 and 3] The equipment and supply liquid were the same as in Example 1, but the degree of vacuum in each vent zone and the temperature in each cylinder block were varied. The operating conditions and results at this time are shown below.
Shown in 1.

[Example-4] The equipment and feed liquid were the same as in Examples-1, 2, and 3, but the polymer concentration of the feed liquid was changed to 45.0% by weight, and the degree of vacuum in the pento zone and the temperature of the cylinder block were changed. It was carried out in the same manner as in Example-3. The operating conditions and results at this time are shown in Table-1.

[Example-5] A carbon tetrachloride solution in which chlorinated propylene with a chlorine content of 28.5 m1i- was dissolved was added to a polymer at a temperature of 21.5 tons.
Using a carbon tetrachloride solution concentrated to H as a stock solution, Example-
It was supplied to the same equipment as 1 to 4. The shaft rotation speed at this time is 7
5 R/IVI, the stock solution feed rate was 18Kii/H. The operating conditions and results at this time are shown in Table-1.

[Example-6] A carbon tetrachloride bath solution in which a chlorinated ethylene vinyl acetate copolymer with a chlorine content of 20.0% by weight was dissolved was concentrated to a polymer concentration of 30.5% by weight, and a carbon tetrachloride solution was used as the stock solution. 1. It was supplied to the same equipment as in Examples 1 to 5. The shaft rotation speed at this time was 70 R/M, and the feed rate of stock solution was 16 Kf/). The operating conditions and results at this time are shown in Table 1.

[Example 7] In Examples 1 to 6, a single screw extruder was used, but here, as shown in Fig. 2 L7, an example using a twin screw extruder was used, and the stock solution was The chlorine content was 52.5% by weight, and the polymer concentration was 38.0% by weight.
It is the same variety as the one used in. The twin-screw extruder used was TEX-65 manufactured by Japan Steel Works, Ltd., with a shaft diameter of 65φ and a cylinder-to-diameter ratio L/D If of 33. In addition, the shape of the shaft is a spirally grooved one, and three seal rings are installed in the middle to seal each vent zone.
Rotates in different directions at a speed of R/M. The raw solution is 150 Kt
The drying bottle 117- was discharged from the die in the form of a rod, and the temperature of the polymer immediately after discharge was 140°C. The operating conditions and results at this time are shown in Table 2.

[Example-8] The reaction solution obtained in Example-5 was changed to a bo-11mer concentration of 20.0% by weight, and this was used as a stock solution, and the same apparatus as in Example-7 was used. The stock solution was supplied at a rate of 1501'l/H, and the rotation speed of the shaft was 120 R/M.

The dried polymer II polymer was discharged in the form of a rod, and the temperature of the polymer immediately after discharge was 110°C. The operating conditions and results at this time are shown in Table 2.

[Example-9] The equipment and feed liquid were the same as in Example jyIU-8, but the degree of vacuum in each vent zone and the temperature of the cylinder block were varied. The dried polymer was discharged in the form of a rod, and the temperature of the boiler II immediately after discharge was 135°C. The operating conditions and results at this time are shown in Table 2.

[Example 10] The stock solution was the same as in Examples 1, 2, 3, 4, and 7, but the polymer concentration was changed, and the twin screw extruder used was are of different Welner types.

The shaft diameter is 36φ, the shape of the shaft is a shallow groove with three grooves, and a companion seal ring that seals the vent zone in the middle rotates in the same direction at a speed of 150 R/M. The stock solution is supplied at a rate of soKg/IH, and the dried polymer is discharged from the die in the form of a rod, and the temperature of the polymer immediately after discharge is 1.
The temperature was 30°C. Table 3 shows the operating conditions and results at this time.
Shown below.

[Example-11] The stock solution had a concentration of 15 wt%, and the rest was the same as Example 9.
The device is the same as Example-10, but the rotation speed of the shaft is t-!
90 R/M, the supply rate was 30 Kf/H. The dried polymer was discharged in the form of a rod, and the temperature of the polymer immediately after discharge was 140°C. The operating conditions and results at this time are shown below.
Shown in 3. The results of Examples 7 to 11 above were obtained using a twin-screw type extruder, but the products obtained had no changes at all and were good.

[Brief explanation of the drawing]

FIGS. 1 and 2 are explanatory diagrams showing embodiments of the present invention, and each reference numeral in one drawing indicates the following. ■Single-screw extruder or twin-screw extruder ■Vacuum generator ■Recovery tank ■Mono pump ■Pulp ■Balloon. ■Pulp ■Pipe ■Pipe [Phase] Pipe ■Condenser @ Condenser @ Condenser [Phase] Concentration tank Procedural Amendment Form Translated August 15, 1985

Claims (1)

[Claims] A method for separating and drying chlorinated polyolefin, which comprises using a vented extruder when separating and obtaining chlorinated polyolefin having a chlorine content of 5 to 60% by weight from a halogenated solvent solution in which it is dissolved.