JPH01146906A - Preparation of chlorosulfonated polyolefin - Google Patents

Abstract

PURPOSE:To carry out the separation, drying and finishing of an object polymer after adding an org. polysiloxane compd. to the reaction liq. contg. a chlorosulfonated polyolefin, thereby preventing the polymer from adhering to the separation, drying and finishing equipment and from being deteriorated by heat. CONSTITUTION:A chlorosulfonated polyolefin is prepared by the chlorination and chlorosulfonation of a polyolefin dissolved in an org. solvent, and the product is separated from the reaction liq., dried and finished after adding to the reaction liq. at least 0.01 pt.wt. org. polysiloxane compd. per 100 pts.wt. chlorosulfonated polyolefin. The org. polysiloxane compd. used herein is a compd. having an average composition of formula I (where R is an alkyl, cycloalkyl, arkenyl, aryl, or aralkyl group, and a is 1.90-2.05), the both terminals of the molecular chain being blocked with trimethylsilyl groups.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to the production of chlorosulfonated polyolefins, and more particularly to a method for separating, drying, and finishing a polymer component from a solution of chlorosulfonated polyolefins.

(Prior Art) Chlorosulfonated polyolefins are produced by dissolving polyolefins in organic solvents and using chlorine and sulfur dioxide gas and/or sulfuryl chloride. Various methods have been proposed for separating and drying the polymer from the reaction-completed liquid containing the chlorosulfonated polyolefin obtained at this time. For example, there is a method using a drum dryer (US Pat. No. 2,923,979), a method using an extruder (Japanese Unexamined Patent Publication No. 57-123201), and the like.

(Problems to be Solved by the Invention) However, since chlorosulfonated polyolefin essentially has the property of softening and sticking at high temperatures, it may not adhere to equipment at the separation and drying operating temperatures of organic solvents. There was a problem that stagnation occurred, resulting in adverse effects on the product due to thermal deterioration.

(Means for Solving the Problems) The present inventor has conducted various studies to solve problems such as adhesion to equipment and deterioration when separating, drying, and finishing chlorosulfonated polyolefins from solvents. When separating, drying, and finishing the chlorosulfonated polyolefin from the reaction-completed solution of the chlorosulfonated polyolefin, at least 0.0% of an organic polysiloxane compound is added to the reaction-completed solution based on 10 parts by weight of the chlorosulfonated polyolefin.
The inventors have discovered that by separating, drying, and finishing the polymer after adding 0.1 part by weight, the adhesion of the polymer to the equipment can be reduced, and as a result, it is possible to prevent the adverse effects on the product caused by retention and thermal deterioration, leading to the present invention.

That is, in the present invention, when separating, drying, and finishing the chlorosulfonated polyolefin obtained by dissolving polyolefin in an organic solvent and chlorinating and chlorosulfonating it from the reaction-finished liquid, 100 weight of the chlorosulfonated polyolefin is added to the reaction-finished liquid. This is a method for producing a chlorosulfonated polyolefin, which comprises adding at least 0.01 part by weight of an organic polysiloxane compound per part of the chlorosulfonated polyolefin, followed by separation, drying, and finishing.

Polyethyl 7 (LLDPE, VLDPE), branched linear density polyethylene (LDPE) isodensity 0.88g/
cc ~ 0.97 g/cc, molecular weight of about 10,000 to 800,000 ethylene homopolymer or ethylene and monomers copolymerizable with ethylene (e.g. propylene, -butene,
Copolymers with α-olefins such as 4-methylpentene and octene, vinyl acetate, acrylic acid, acrylic esters, and polypropylene are used.

The organic solvent used in the reaction is an inert solvent for chlorination and chlorosulfonation reactions, and is usually carbon tetrachloride,
Preferred are halogenated hydrocarbons such as chloroform, methylene chloride, ethane tetrachloride, ethylene tetrachloride, and trichlorofluoromethane.

The reaction may be carried out by a known method, in which the polyolefin is dissolved in an organic solvent, and chlorine and sulfur dioxide gas and/or sulfuryl chloride are reacted in the presence of a radical catalyst (for example, 2,2'-azobisisobutyronitrile) or ultraviolet light. It is implemented by letting

Furthermore, an amine compound such as pyridine may be added as a co-catalyst. The resulting chlorosulfonated polyolefin typically contains 15 to 50% by weight chlorine and 0.2 to 2.0% by weight.
Contains sulfur.

The average compositional formula of the organic polysiloxane compound added to the reaction-completed solution is Ra Si 05-w+1, where R is a methyl group, an ethyl group, a propyl group,
Alkyl groups such as butyl group, 2-ethylbutyl group, octyl group, cycloalkyl group such as cyclohexyl group, cyclopentyl group, alkenyl group such as vinyl group, hexenyl group, phenyl group, tolyl group, xylyl group, naphthyl group, diphenyl group aryl groups such as benzyl groups, aralkyl groups such as phenylethyl groups, or chloromethyl groups and trifluoropropyl groups in which some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with halogen atoms, cyano groups, etc. 2-cyanoethyl group, 3-cyanopropyl group, etc.; a is 1.90 to 2.05, 4, and both molecular chain ends are Although it is capped with a trimethylsilyl group, it may be capped with a hydroxyl group or a dialkoxy group at both ends of the molecular chain.

It is necessary to add at least 0.01 part by weight of these organic polysiloxanes to 100 parts by weight of the chlorosulfonated polyolefin. If the amount is less than this, the adhesion prevention effect will be insufficient. Further, even if the amount added is very large, it is not economical because it is expensive compared to the increased effect. Preferably it is about 0.1 to 10 parts by weight.

This organic polysiloxane is added to the reaction solution of the chlorosulfonated polyolefin. The timing of addition may be as long as it is after the completion of the reaction. If it is added before the reaction, the effect in the solvent separation and drying process will not be achieved.

The equipment used in the present invention for separating, drying, and finishing the chlorosulfonated polyolefin from an organic solvent solution is a double drum dryer or an extruder having a devolatilizing function.

A double drum dryer supplies the reaction-completed solution of chlorosulfonated polyolefin between two rotating rolls heated to 100 to 200°C, and while the solution is being carried on the roll surface, the solvent evaporates, resulting in chlorosulfonation. This is a method in which the polyolefin is rotated 374 times and then peeled off as a film. At this time, according to the method of the present invention, adhesion to the blade used for stripping the film is reduced, and no residue is left on the drum surface, thereby preventing thermal deterioration due to retention and adverse effects on the product.

An extruder with a devolatilization function is an extruder that has a vent function for discharging solvent vapor generated by volatilization within the extruder to the outside of the system, and usually contains 40% by weight or more of the reaction-completed liquid of chlorosulfonated polyolefin. The pre-concentrated solution is supplied to the tank, and while being heated from the barrel, it is kneaded and mixed by a screw.
Without stirring, the solvent is removed by applying a vacuum using a Robentok.

At this time, according to the method of the present invention, adhesion and retention on the screw surface is reduced, and thermal deterioration and adverse effects on the product are prevented.

Furthermore, the quality of the chlorosulfonated polyolefin obtained by the present invention is almost the same in physical properties as that obtained by known methods.

(Examples) The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited to these.

Furthermore, the reaction solutions used in these Examples and Comparative Examples were synthesized and used as follows.

100 parts by weight of carbon tetrachloride in a glass-lined reaction vessel;
Linear low density polyethylene (density 0.925g/cc
, °melt index 2.5) was charged, and after pressurizing to 2.0 kg/ctl (gauge) with nitrogen, the inner hot water was heated to 100°C and the polyethylene was dissolved by stirring. In this solution, 3.0 parts by weight of a solution of 0.3 parts by weight of α, α'-azobisisobutyronitrile dissolved in 100 parts by weight of carbon tetrachloride and 0.0001 parts by weight of pyridine were added.
After adding 14.5 parts by weight of sulfuryl chloride and 0.3 parts by weight of α,α'-azobisisobutyronitrile in 100 parts by weight of carbon tetrachloride, 6 parts by weight of a solution was added continuously for 4 hours. The reaction was allowed to proceed by addition of During this reaction, the temperature was 100°C, the pressure was 3.0 kg/
a+! (gauge). Hydrogen chloride and sulfur dioxide gases generated as the reaction progressed were neutralized and removed with an 8% by weight aqueous sodium hydroxide solution. As a result of analysis, the polymer in this reaction solution contained 34.0% by weight of chlorine and 1% by weight of chlorine.
．． It was a chlorosulfonated polyolefin containing 0.9% by weight sulfur.

After the completion of the reaction, the internal pressure of the reactor was increased to 3.0 kg/c++ in 2 hours.
! The pressure was lowered linearly from (gauge) to 400 mmHgabs to remove dissolved acidic gas. At this time, the temperature on the jacket side of the reaction can was controlled so that there was no difference in temperature from the polymer solution (temperature inside the reaction can). 1 per 100 parts by weight of the chlorosulfonated polyolefin as a stabilizer.
．． 4 parts by weight of 2.2'-bis(4-glycidyloxyphenyl)propane were added. The polymer content of this reaction-completed liquid was about 10% by weight.

Example 1 0.1 part by weight of methylphenylpolysiloxane (TSF431 manufactured by Toshiba Silicone ■) with a viscosity of 100 centistokes (25°C) was added to the reaction completed liquid per 100 weight of chlorosulfonated polyolefin, and the solvent was dried using a double drum dryer. Separation, drying, and finishing were carried out.

The double drum dryer used was composed of two cylindrical rolls with a diameter of 30 cm and a length of 30 cm, each with a chrome-plated surface. The roll was heated from inside using steam, and the surface temperature was adjusted to 150°C.

The rolls were rotated at a speed of 3 RPM in the meshing direction.

The clearance between the two rolls was 0.3 +u. The sides of the roll were also sealed with plates or weirs. The polymer solution is fed to the upper part of the roll, and the polymer solution concentrated at the upper part passes through a section with a clearance of 0.3 m, adheres to the lower surface of the mouth in the form of a film, and is dried.

The polymer film was then stripped with a knife held at an angle to the roll by a spring to yield a dry film of chlorosulfonated polyolefin.

A solution containing 10% by weight of polymer was fed to this double drum dryer at a rate of 20 kg/hour. The amount of solvent contained in the dried chlorosulfonated polyolefin obtained was 0.25% by weight, and the quality was also good. Furthermore, no film was observed to adhere to the blade for stripping the film from the roll, and no film was observed to adhere to the roll surface. Therefore, no stains due to polymer deterioration were observed on the roll surface after 168 hours of operation, and no deteriorated deposits were found on the blade surface.

Example 2 After adding 5 parts by weight of dimethylpolysiloxane having a vinyl group (SH-410 Silicone Gum Tore Silicone ■) to 100 parts by weight of chlorosulfonated polyolefin to the reaction completed liquid, the preheater was turned on using a pump. The chlorosulfonated polyolefin was flushed from the upper part of the chamber under reduced pressure to obtain a polymer solution having a concentration of 45% by weight. This was separated from the solvent, dried, and finished using an extruder with a devolatilizing function.

The extrusion dryer used was Toshiba Machine's TEM-50, with a shaft diameter of 57 mm and a cylinder-to-diameter ratio L/D of approximately 31.6.
It is. This twin-screw extruder is composed of 11 cylinder blocks. This block configuration is C1,
When expressed as C2, C3,...Ctr, C1 is the raw material supply block, Ca % Cb, Ctr
, Coo is a professional mouth with vent l. The depressurization degree of each vent is C4; 300m
ml1gabs%C6; 100wHgabs,
Ca; 15 mHgabs% C10; 15 m
mHgabs. Also, the temperature of each block is 160℃ for C, C, C3, C4, Cs, C
b is 150 ”c, C,, C, is 130℃, C1, C1
° and C11 were adjusted to 100°C using an electric heater and cooling water. The screw is helically grooved, with a disc in the middle to seal each vent zone, and 15 ORPM in the same direction.
is rotating at a speed of A single-screw extruder with a shaft diameter of 90 m and a cylinder-to-diameter ratio L/D of about 7 was attached to the tip of this twin-screw extruder. The screw of this -screw extruder was rotated at a speed of 15 RPM. A die with a hole of 101 m in diameter was installed at the tip of this extrusion molding machine, and dried chlorosulfonated polyolefin was discharged in the form of a rope from this die.

A solution containing 145% by weight of polymer was fed to this extruder at a rate of 90 kg/hour. The amount of solvent contained in the chlorosulfonated polyolefin discharged from the extrusion molding machine was 0.
The content was 37% by weight, which was good in terms of quality. Furthermore, no degraded polymer was observed in the dried polymer rope after 480 hours of continuous operation.

After 480 hours of operation, the apparatus was disassembled and the screw and cylinder of the twin-screw extruder were inspected, but there was almost no polymer adhesion and no deposits due to thermal deterioration were observed.

Example 3 After adding 1 part by weight of vinyl group-containing dimethylpolysiloxane (SH-410 silicone gum manufactured by Toray Silicone Co., Ltd.) used in Example 2 to the reaction completed liquid, 1 part by weight per 100 parts by weight of chlorosulfonated polyolefin was added. The solution was flushed from the upper part of the chamber under reduced pressure via a preheater to obtain a polymer solution of chlorosulfonated polyolefin having a concentration of 18% by weight. This was separated from the solvent, dried, and finished using a double drum dryer.

The equipment and conditions used were the same as in Example 1.

The polymer solution was fed at a rate of 15 kg/hour, and the amount of solvent contained in the obtained chlorosulfonated polyolefin was 0.1
It was 8% by weight, and there was no problem in terms of quality. No film was observed to adhere to the blade for stripping the film from the roll, and there was no adhesion to the roll surface. After 240 hours of operation, there was no deposit due to polymer deterioration on the roll surface, and there was no deteriorated material on the blade surface.

Comparative Example 1 To 100 parts by weight of chlorosulfonated polyolefin, 1 part by weight of methylphenylpolysiloxane O, OO, which was used in Example 1, was added to the reaction-completed liquid, and separated from the solvent under the same conditions as in Example 1. , drying and finishing. The amount of solvent contained in the dried chlorosulfonated polyolefin obtained was 0.27 [t%].

Looking at the operating conditions, it was observed that the film was attached to the blade for stripping the film from the roll, and it seemed to be a little sticky.

After 168 hours of operation, the roll surface showed brown adhesion due to polymer deterioration, and some of the blade surfaces were also degraded due to accumulation of adhesion. At this time, it was also confirmed that brownish polymer was mixed into the film that was peeled off from the roll.

Comparative Example 2 Separation from the solvent, drying, and finishing were carried out in the same manner and under the same conditions as in Example 2 without adding organic polysiloxane to the reaction-completed liquid. The amount of solvent contained in the obtained chlorosulfonated polyolefin was 0.33% by weight.

In this case, the amount started to be seen after 450 hours of continuous operation. After 480 hours of operation, the operation was stopped and the equipment was inspected, and a brown-brown deposit was observed partially in the middle of the screw of the twin-screw extruder, which was thought to be caused by the adhesion and retention of the polymer.

(Effects of the Invention) According to the present invention, when the chlorosulfonated polyolefin is separated from the solvent, dried, and finished, it is possible to prevent the adverse effects on the product due to adhesion and retention in the equipment.

Patent applicant: Denki Kagaku Kogyo Co., Ltd.

Claims (1)

[Claims] When separating, drying, and finishing the chlorosulfonated polyolefin obtained by dissolving polyolefin in an organic solvent and chlorinating and chlorosulfonating it from the reaction-finished liquid, chlorosulfonated polyolefin 10 is added to the reaction-finished liquid.
A method for producing a chlorosulfonated polyolefin, which comprises adding at least 0.01 parts by weight of an organic polysiloxane compound to 0 parts by weight, followed by separation, drying, and finishing.