JPS62119210A - Vinyl chloride resin manufacturing method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention Field of Application of "fr, Length" 1 The present invention is directed to the use of vinyl chloride resins having favorable properties such as those obtained by emulsion polymerization, in a preferred form such as those obtained by suspension polymerization. The present invention relates to a method for producing a vinyl chloride resin that can be produced with less adhesion to can walls, easy particle size control, and a sharp particle size distribution.

"Prior Art" Vinyl chloride polymers produced by emulsion polymerization have fine polymer particles and excellent processability.

On the other hand, by the suspension polymerization method, vinyl chloride polymer was
Because the particles produced during polymerization are coarse, they can be easily dehydrated, washed, and dried after the polymerization reaction, and the resulting polymer has excellent thermal stability, electrical properties, transparency, weather resistance, etc.
Easy to handle during processing.

Attempts to produce vinyl chloride-based TH fats having favorable properties such as those obtained by emulsion polymerization in a preferred form such as polymers obtained by suspension polymerization are known, for example, as described in Japanese Patent Publication No. 30834/1983. It is.

According to this publication, 5 to 90% of the total amount of the polymer to be finally obtained is produced by emulsion polymerization, and then water, a suspending agent, an oil-soluble polymerization initiator are added to the reaction system, and the remaining amount is The polymerization was carried out by suspension polymerization method. This known method has similar characteristics to vinyl chloride fruit resin produced by emulsion polymerization, and although post-treatments similar to suspension polymerization can be carried out, the particle size distribution of the resulting polymer remains constant. It also has the disadvantage that the particle size distribution is quite wide.
In the current field of vinyl chloride resin processing, where technological progress is rapid, it has not always been possible to be satisfied. i4c
Physically speaking, in this method, after the latex is obtained by emulsion polymerization, the coarse particles that are produced as a by-product in the latex remain as they are, and because the latex agglomerated particles are not controlled at the latex stage, the latex is subsequently suspended. The particle size distribution of vinyl chloride resin produced by turbid polymerization is wide and has a large variation, which causes so-called clumps and fissures to occur in molded products, making it often impossible to put it to practical use. . Furthermore, during suspension polymerization, polymer scale often adhered to the can wall.

"Problems to be Solved by the Invention" The present inventors have made use of the features of the prior art to obtain a vinyl chloride resin that has favorable properties similar to those obtained by emulsion polymerization by suspension polymerization. The present invention was achieved through intensive research into a method for producing a vinyl chloride resin that can be produced in a preferred form, has less adhesion to can walls, is easy to control particle size, and has a sharp particle size distribution.

"Means for Solving the Problems" The gist of the present invention is to produce a vinyl polymer latex by an emulsion polymerization method or a fine suspension polymerization method. After removing the coarse grains, the latex is broken to form agglomerated latex particles, and in the presence of the agglomerated latex particles,
A method for producing a vinyl chloride-based If resin 5iI, which is characterized by carrying out suspension polymerization of vinyl chloride or a mixture of vinyl chloride and a monomer copolymerizable therewith.

The present invention will be explained in detail below.

The +1 mer to which the method of the present invention can be applied includes vinyl chloride alone and a combination of vinyl chloride and one or more vinyl monomers copolymerizable therewith.

Examples of vinyl monomers mentioned here include vinyl acetate, styrene, acrylonitrile, acrylic ester,
Oil-soluble monomers such as methacrylic acid ester and ethylene; Water-soluble monomers such as acrylic acid, methacrylic acid, maleic acid, and crotonic acid; Vinyl monomers such as sodium acrylate, sodium chloride, and calcium acrylate Examples include inorganic salts of polymers. In addition, examples of mono-European monomers include vinyl monomers having a polyfunctional group copolymerizable with vinyl chloride, such as novinylbenzene, diallyl phthalate,
Noarylmalae) etc. can be applied. These vinyl monomers having polyfunctional groups yield polymers having crosslinked structures.

In order to effectively achieve the present invention, it is first necessary to carry out emulsion polymerization or fine suspension polymerization. vinyl chloride alone,
or vinyl chloride and a desired lI selected from the above monomer group
The tm compound, water, an emulsifier and a water-soluble polymerization initiator, or an oil-soluble polymerization initiator, and in some cases a pH control agent are placed in a reactor, and after substitution with an inert gas, polymerization is performed.

As the emulsifier that can be used in emulsion polymerization, water-soluble emulsifiers are suitable, and anionic emulsifiers are particularly desirable. The amount of emulsifier is 2. OP) 1M or less is desirable.

As the water-soluble polymerization initiator, hydrogen peroxide, potassium persulfate, ammonium persulfate, etc. are used.

As the oil-soluble polymerization initiator, an initiator that generates 7-lilanocal, such as benzoyl peroxide, lauroyl peroxide, and di-tert-butyl peroxide, is used. Additionally, oxidation-reduction (redox) initiators can also be used.

Using the composition described in -1- above, 80% or more of the latex was polymerized by an emulsion polymerization method or a fine suspension polymerization method, and coarse particles of 60 mesh or more were removed from the obtained latex, and water and suspension were added. A clouding agent and an electrolyte are added to break up the latex and form a coagulated latex.

When destroying the latex, add water so that the solid content ratio is 25% or less and destroy the @turbidity into the polyvinyl chloride.
0.5% is added, and while stirring at a temperature of 30 to 60°C, the electrolyte is gradually added and coagulated.

As the suspending agent, those commonly used in suspension polymerization can be used. For example, various saponified products of polyvinyl acetate,
Examples include various water-soluble cellulose derivatives, maleic acid copolymers, gelatin, etc., and these may be used alone or in combination with two or more types.
Can also be used in combination. Further, these suspensions M and a certain type of surfactant can also be used in combination.

Further, as the electrolyte, calcium chloride, calcium acetate, water-soluble alkali metal or alkaline earth metal salt, etc. are used.

A part or all of the coagulated latex, vinyl chloride alone or vinyl chloride and a desired monomer selected from monomer group 11, as well as water, a suspending agent, and an oil-soluble polymerization initiator are added to a reactor. After replacing with inert gas, suspension polymerization is carried out.

The oil-soluble polymerization initiator used as a suspending agent in suspension polymerization is +iiij
The ones mentioned above can be used.

As mentioned above, the method of the present invention is characterized by combining the emulsion polymerization method, the suspension molding method, and the S molding method, but the polymerization conditions for each of the emulsion polymerization method and the suspension polymerization method may be changed arbitrarily. For example, the polymerization temperature may be different, and the degree of polymerization of the polymer obtained by emulsion polymerization may be different from the degree of polymerization of the polymer obtained by suspension polymerization. Furthermore, during the polymerization process using both types of methods, the monomer can be added stepwise or continuously to the reaction system while the polymerization is continued. Further, when producing a copolymer, polymerization by emulsion polymerization and polymerization by suspension polymerization may be carried out using different monomers.

The polymer obtained by the method of the present invention is different from a mere mixture of fine particles produced by the emulsion polymerization method and the fine #I suspension type method and coarse particles produced by the suspension polymerization method. It has both characteristics. First, when polymerization is carried out by the emulsion polymerization method, ordinary fine particles of 2 microns or less are obtained using a conventional emulsion polymerization reactor 41t.

Furthermore, fine particles of 2 microns or less can be similarly obtained by microms turbidity polymerization. When these fine particles are broken into aggregated particles and subjected to suspension polymerization, the polymer produced in the suspension polymerization process wraps around the aggregated particles and has a particle diameter of 20 to 500 microns (average particle size). It grows to a size of approximately 150 mikuun.

Therefore, after the completion of the reaction, salting out as in the usual emulsion polymerization method is not required, and dehydration, washing and drying can be easily carried out as in the usual suspension polymerization method.

The method of the present invention and the vinyl chloride resin obtained by the method of the present invention have the following excellent characteristics.

1. In the conventional technology, the particle size distribution was not constant and spread over a wide range, but according to the present invention, the particle size distribution becomes sharp and can be easily controlled.

2. Because the particle size distribution has become sharper, fish eyes (hereinafter referred to as F and E) are reduced compared to conventional products.

31? &During the turbid polymerization, the amount of polymer scale attached to the can wall was significant, but it was reduced in the present invention.

4. The polymer obtained according to the present invention has good deltability and therefore has excellent processability.

Next, the first implementation of the present invention! The present invention will be explained in detail with reference to examples, but the present invention is not limited to the following examples unless the scope thereof is exceeded.

Example 1 Water 1000g Vinyl chloride 500g Sodium lauryl sulfate 0.5g Potassium persulfate 0.3° bisulfite
0.3g bicarbonate of soda 0.4g above,
The composition was added to a stainless steel autoclave with a capacity of 31 and equipped with a stirrer, and after replacing with nitrogen, emulsion polymerization was carried out at 58°C for 5 hours with stirring at 200 rpm, and unreacted vinyl chloride was degassed and kneaded. Separated by production. The polymerization rate of the initially charged monomer was 90%, the latex had a particle size of 0.2 microns, and a solid content of 30%.Since this contained coarse particles, it was filtered through a 100 mesh.

The latex was diluted with water to a solid content of 25%, 30% of a 2% polyvinyl alcohol aqueous solution was added, and the mixture was gradually stirred at 500 rpm in a stainless steel autoclave equipped with a Pit stirrer at a temperature of 30°C. A calcium chloride aqueous solution was added to cause flocculation. The particle size distribution of these eight fruits was measured using a particle size distribution analyzer after centrifugal sedimentation. The average particle size was 150 microns.

Next, using the latex, add 3 parts of water to a stainless steel autoclave equipped with a stirrer.
00g agglomerated latex 1000° vinyl chloride monomer 3001r polyvinyl alcohol 2% liquid io.

2.1 g of lauroyl peroxide was added to each, and suspension polymerization was carried out at 58° C. for 8 hours. After the polymerization reaction is completed, the dechlorinated vinyl monomer is washed, dehydrated, and dried.
A polyvinyl chloride resin was obtained.

The total amount of polyvinyl chloride at this time was 500 g.

In addition, almost no adhesion to the can wall of the stainless steel autoclave with a stirrer was observed. The average particle diameter of the obtained polyvinyl chloride was 150 microns, and the particle size distribution is shown in Table 1.

Table 1 Next, a sheet was prepared using the conventional method using this polyvinyl chloride in the following blending amount, and F and E (fish eye) were measured and found to be 1 piece/100 am2. For comparison, a sheet of polyvinyl chloride obtained by carrying out suspension polymerization without filtering the latex obtained by the emulsion polymerization method of Example 1 was similarly prepared, and F and E were measured. However, the number was 7 pieces/100 cm.

Polyvinyl chloride 100 parts by weight plasticizer (r
) OP Ni-2-ethylhexyl 7 tallate) 50 Stabilizer 1 Carbon 0.5 Also, 3 parts by weight of butyltin maleate was added to 100 parts by weight of this polyvinyl chloride, and after kneading with heated rolls, the mixture was heated at 180°C. As a result of a thermal stability test in an oven, the polymer obtained in this example was colored pale yellow in 90 minutes, and although the degree of coloration was slightly inferior to that of a commercially available suspension polymerization method, It showed much better thermal stability than similarly colored commercially available emulsified polymers.

In addition, using a formulation similar to that used for measuring F and E, the delta time at 170°C was measured using Prabender Blast Gras 7, and the result was 80 seconds. Average degree of polymerization obtained by polymerization method: 1
The deltation time of the 050 polymer was 150 seconds. The results show that the processability of the polymer obtained by the present invention is far superior to that of the polymer obtained by suspension polymerization.

Comparative Example 1 The latex obtained in Example 1 was filtered through a 100/y filter, diluted with water to a solid content of 25%, 30w1 of a 2% polyvinyl alcohol aqueous solution was added, and the latex was soaked without aggregation. .

Water 300
g latex 1000FK vinyl chloride monomer 300FI polyvinyl alcohol 2% solution 10 g lauroyl peroxide 2.1 g were each added to 31 stainless steel autoclaves equipped with a stirrer, and suspension polymerization was carried out at 58° C. for 8 hours. After the polymerization reaction was completed, there was a lot of adhesion to the can wall of the stainless steel autoclave with a stirrer, and the waste water became cloudy, and the amount of polyvinyl chloride in the waste water was 25. Met. The amount of polyvinyl chloride obtained at this time was 400 g, and the average particle size was 300 microns, which was very coarse.

The particle size distribution is shown in Table 2.6 Table 2 Unless the latex is coagulated and polymerized, the wastewater becomes cloudy and good polyvinyl chloride cannot be obtained, so Comparative Example 1 cannot be said to be an appropriate polymerization.

Example 2 1000g of latex obtained in the same manner as Example 1
After 100 meshes were diluted with water to a solid content of 25%, 30ml of 2% methyl cellulose aqueous solution was added, and the mixture was stirred at 500 rpl+1 in a stainless steel autoclave with a stirrer prepared separately at a temperature of 30°C. While doing so, an aqueous calcium chloride solution was gradually added to cause flocculation. This al! The particle size distribution of the product was measured using a particle size distribution analyzer after centrifugal sedimentation, and the average particle size was 150 microns.

Next, using the latex, add 3 parts of water to a stainless steel autoclave with a stirrer.
00g agglomerated latex 1000° vinyl chloride monomer 300° methylcellulose 10g lauroyl peroxide 2.1g were added and suspension polymerized at 58°C for 8 hours. After the polymerization reaction is completed, dechlorination and nil monomer, washing,
After dehydration and drying, a polyvinyl chloride resin was obtained. The total amount of polyvinyl chloride at this time was 500 g.

In addition, adhesion to the can wall of a stainless steel autoclave with an agitator,
was rarely seen.

The average particle diameter of the obtained polyvinyl chloride was 150 microns, and the particle size distribution was shown in Table 3.Next, a sheet was prepared using the conventional method using this polyvinyl chloride in the following blending amount,
F and E were measured and found to be 3 pieces/100 cm.For comparison, the latex obtained by the emulsion polymerization method of Example 2 was subjected to suspension polymerization without filtration. When sheets of vinyl chloride were prepared in the same manner and F and E were measured, 10 sheets were 7100 cm''.

Polyvinyl chloride 100 parts by weight plasticizer (D
OP: No 2-ethylhexynyl 7 tallate) 50 Stabilizer.

Carbon 0,5 and this polyvinyl chloride 100w'W#, dibutyltin maleny)
Lira (after adding it part and kneading with a heating roll,
As a result of testing thermal stability in gear open at 180℃,
The polymer obtained in this example was colored pale yellow in 85 minutes, and the degree of coloration was slightly inferior to that of a polymer produced by a commercially available suspension polymerization method, but it was comparable to a polymer produced by a commercially available emulsion method that was similarly colored in 40 minutes. showed much better thermal stability in comparison.

In addition, using the same formulation as used for the measurement of F and E,
When the gelation time was measured using Brabender Plastogura 7, it was 75 seconds, and for comparison, the gelation time of a polymer with an average degree of polymerization of 1050 obtained by a commercially available suspension polymerization method was 150 seconds. there were. The results show that the processability of the polymer obtained by the present invention is far superior to that of the polymer obtained by suspension polymerization.

Example 3 Water 120
0cc Vinyl chloride 600g Sodium lauryl sulfate 0.7g Potassium persulfate 0.4g The above composition was added to a volume of 3
The autoclave was placed in a stainless steel autoclave equipped with a stirrer, and the mixture was purged with nitrogen. After emulsion polymerization was carried out at 58°C for 5 hours with stirring at 200 rpm, unreacted vinyl chloride was separated by degassing. Initially, the polymerization rate of the monomers charged was 9
6 or less, which was a latex with a particle size of 0.2 microns and a solid content of 30%, was filtered and coagulated in the same manner as in Example 1.

Next, using the latex, water was added to a stainless steel autoclave equipped with a stirrer.
0 g of agglomerated latex 9 (10 g of vinyl chloride monomer, 600 g of 2% polyvinyl alcohol solution, 3 g of lauroyl peroxide) were added, and suspension polymerization was carried out at 58°C for 8 hours. After the completion of the polymerization reaction,
When the dechlorinated vinyl moamer was washed, dehydrated and dried to obtain polyvinyl chloride oil, the total amount of polyvinyl chloride was 7.
40 g, and almost no adhesion to the can wall of the stainless steel autoclave with a stirrer was observed.

The average particle diameter of the obtained polyvinyl chloride was 100 microns, and the particle size distribution is shown in Table 4.

Table 4 When this polyvinyl chloride was measured for F and E in the same manner as in Example 1, it was found to be 1 piece/100 cm2.

The polymer obtained in this example was prepared in the same manner as in Example 1.
When the gelation time was measured at 70'C, it was 80 seconds as in Example 1. This result shows that the processability of the polymer obtained by the present invention is far superior to that of the polymer obtained by suspension polymerization6. After adding 3 parts by weight of maleate and kneading with heated rolls, 1
As a result of a thermal stability test in a gear oven at 80°C, the polymer obtained in this example was colored pale yellow in 90 minutes, and the degree of coloration was slightly inferior to that of a commercially available suspension polymerization polymer. 4
It showed much better thermal stability than a similarly colored commercially available emulsified polymer at 0 minutes.

Example 4 Water 1000
g Vinyl chloride 475g Vinyl acetate 25g Sodium lauryl sulfate 0.5+? potassium persulfate
0.3g sodium bisulfite
0.3g bicarbonate of soda 0.4g
The above composition was added to a stainless steel autoclave with a stirrer of capacity I231, and after purging with nitrogen, 200 rp-
After emulsion polymerization was carried out at 58° C. for 5 hours with stirring, unreacted vinyl chloride and vinyl acetate were separated by degassing operation.

The polymerization rate of the initially charged monomer was 90% and the particle size was 0.2.
It is a latex with a solid content of 30% in microns, and because it contains coarse particles, it passes through 100 meshes.
Dilute 1000 g of the tex with water to a solid content of 25%, add 30 ml of 2% polyvinyl alcohol solution,
While stirring at 500 rpm in a separately prepared stainless steel autoclave equipped with a stirrer at a temperature of 0° C., a calcium chloride solution was gradually added to cause aggregation. The particle size distribution of this aggregate was measured using a particle size distribution analyzer after centrifugal sedimentation, and the average particle size was 150 microns.

Next, using the latex, add water to a stainless steel autoclave equipped with a stirrer.
00g agglomerated latex 1000g vinyl chloride moa 7- 300g polyvinyl alcohol 2% fi 10゜lauroyl peroxide 2.1+? was added, and suspension polymerization was carried out at 58°C for 8 hours. After the polymerization reaction was completed, the dechlorinated vinyl monomer was removed, washed, dehydrated and dried to obtain a polyvinyl chloride resin. The total amount of polyvinyl chloride at this time was 500 g.

In addition, almost no adhesion to the can wall of the stainless steel autoclave with a stirrer was observed.

The average particle diameter of the obtained polyvinyl chloride was 150 microns, and the particle size distribution is shown in Table 5.

Table 5 Next, a sheet was made using the conventional method using the following blending amount of polyvinyl chloride, and F and E were measured.
It was 00cI112. For comparison, a sheet of polyvinyl chloride obtained by carrying out suspension polymerization without filtration of the latex obtained by the emulsion polymerization method of Example 4 was prepared in the same manner, and F and E were measured. 7 pieces/100 am2
Met.

Polyvinyl chloride 100 heavy plastic plastic,'l
'1 (DOP di-2-ethylhexyl 7-talate) 5
0 Stabilizer 1 Carbon 0.5 Also, 100 parts by weight of this polyvinyl chloride was added with 3 parts dibutyltin maleate, kneaded with heated rolls, and then tested for thermal stability in a gear oven at 180°C. The polymer obtained in this example was colored pale yellow in 80 minutes, and although the degree of coloring was slightly inferior to that of the polymer produced by the commercially available suspension polymerization method, it was colored in the same way in 40 minutes as the polymer produced by the commercially available emulsion method. showed much better thermal stability in comparison.

In addition, when the delification time was measured using Brabender Blastography 7 using the same formulation used in the measurements of F and E, it was 75 seconds. The deltation time of the polymer with a y homopolymerization degree of 1050 was 150 seconds. The results show that the processability of the polymer obtained by the present invention is far superior to that of the polymer obtained by suspension polymerization.

Example 5 Water 1000
cc fluoroyl peroxide 9g lauryl sulfate 6g lauryl alcohol 3g The above composition was added to a stainless steel autoclave equipped with a stirrer made by Yongen 31, and after purging with nitrogen, 60g of vinyl chloride was added and the mixture was heated at 200 rpm.
t' The temperature was maintained at 35° C. with stirring. After stirring uniformly, the emulsifier was used for several months to disperse the dispersion to the desired droplet size. After completing the transfer, the dispersion was transferred to a stainless steel autoclave equipped with a stirrer, which had been purged with nitrogen. The temperature of the tank was raised to 58°C, and fine suspension polymerization was carried out. The latex had a particle size of 0.4 microns and a solid content of 32%, and since it contained coarse particles, it was filtered through a 100-mesh filter.

Dilute 1ooo8 of the latex with water to a solid content of 25%, add 32ml of 2% polyvinyl alcohol aqueous solution,
While stirring at 500 m in a separately prepared stainless steel autoclave with a stirrer at a temperature of 30°C, an aqueous calcium chloride solution was added to cause aggregation.

The particle size distribution of this aggregate was measured using a precision distribution measuring device after centrifugal sedimentation, and the average particle size was 150 microns.

Next, using the latex, add water to a stainless steel autoclave equipped with a stirrer.
300g agglomerated latex 100
g Vinyl chloride Vinyl chloride - 300g Polyvinyl alcohol 2% fi 10g Add lauroyl peroxide 2.1g, 58"
Suspension polymerization was carried out at C for 8 hours. After the polymerization reaction is completed, the dechlorinated vinyl monomer is washed, dehydrated and dried to obtain polyvinyl chloride 4j (
I got *. The total weight of polyvinyl chloride at this time was 500 g.

In addition, almost no adhesion to the can wall of the stainless steel autoclave with a stirrer was observed.

The average diameter of the obtained polyvinyl chloride was 150 microns, and the particle size distribution is shown in Table 6.

Table 6 Next, m
When I made a sheet and measured F and E, it was 1 piece/
It was 100 cra2. For comparison, a sheet of polyvinyl chloride obtained by carrying out suspension polymerization without filtration of the latex obtained by fine suspension polymerization in Example 5 was prepared in the same manner, and F and E were measured. 7 pieces/100cm
It was 2.

Polyvinyl chloride, 100 parts by weight plasticizer (D
OP: No 2-ethylhexyl 7 tallate) 50 Stabilizer 1 Carbon Q, 5 Add 3 parts of diptyltin maleate to this polyvinyl chloride 100i1'f part, and knead with a heating roll.
As a result of testing thermal stability in a gear oven at 180°C,
The polymer obtained in this example was colored pale yellow in 90 minutes, and although the degree of coloration was slightly stronger than that obtained by the commercially available suspension polymerization method, it was compared with a polymer obtained by the commercially available emulsification method that was similarly colored in 40 minutes. showed much better thermal stability.

In addition, when the gelation time was measured using Prabender Plastogura 7 using the same formulation as in the measurement method of F and E, it was 85 seconds, which was compared to the average obtained by the commercially available suspension polymerization method. The gelation time of the polymer with a polymerization degree of 1050 was 150 seconds. The results show that the processability of the polymer obtained by the present invention is far superior to that of the polymer obtained by suspension polymerization.

Claims (1)

[Claims] A vinyl chloride polymer latex is produced by an emulsion polymerization method and a fine suspension polymerization method, and after removing coarse particles of 60 mesh or more that are produced as a by-product during the production of the latex, this latex is destroyed to obtain aggregated latex particles. 1. A method for producing a vinyl chloride resin, which comprises suspending and polymerizing vinyl chloride or a mixture of a monomer copolymerizable with vinyl chloride in the presence of the latex particles.