JPH0617370B2 - Polymer scale adhesion prevention method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for preventing polymer scale from adhering to the inner wall surface of a polymerization vessel or the like in the polymerization of a monomer having an ethylenic double bond.

[Conventional technology]

In a method of producing a polymer by polymerizing monomers in a polymerization vessel, it is known that the polymer adheres to the inner wall surface of the polymerization vessel as a scale. If polymer scale adheres to the inner wall surface of the polymerization vessel, the yield of the polymer and the cooling capacity of the polymerization vessel will decrease, and the adhered polymer scale will peel off and enter the product, resulting in deterioration of the quality of the product polymer. Further, there are disadvantages such that a great amount of labor and time are required for removing the polymer scale.

Conventionally, as a method of preventing the adhesion of polymer scale to the inner wall surface of the polymerization vessel, for example, a method of applying a polar compound, dye, pigment, etc. to the inner wall surface (Japanese Patent Publication Nos. 45-30343 and 45-3).
No. 0835), a method of applying an aromatic amine compound (Japanese Patent Application Laid-Open No. Sho.
51-50887), a method of applying a reaction product of a phenolic compound and an aromatic aldehyde (JP-A-55-54317), and the like.

These methods are effective for preventing polymer adhesion in the polymerization of vinyl halide monomers such as vinyl chloride or a monomer mixture containing the monomer as a main component and a small amount of a monomer copolymerizable therewith. Is.

[Problems to be Solved by the Invention]

However, in the above-mentioned conventional method, the scale prevention effect depends on various conditions of the polymerization such as the type of monomer used, the mixing ratio of each component used, the type of polymerization catalyst, the type of polymerization, the material of the inner wall of the polymerization vessel, etc. However, it was difficult to effectively and surely prevent the polymer scale from adhering to the inner wall surface of the polymerization vessel, the stirring blade, the stirring shaft, the baffle, etc. with which the monomer comes into contact during the polymerization.

Therefore, an object of the present invention is to provide a method capable of always effectively preventing scale adhesion regardless of various polymerization conditions such as the type of monomer used.

[Means for Solving the Problems]

The present invention is a method for preventing the adhesion of polymer scale in the polymerization of a monomer having an ethylenic double bond in a polymerization vessel, as a solution to the above-mentioned problems, and a polymerization vessel inner wall surface, and preferably (A) at least one selected from a reaction product of tannins and aldehydes and an ester derivative of tannins, and (B) a dye and a pigment in advance in the other portion with which the monomer contacts during the polymerization. The present invention provides a method for preventing adhesion of a polymer scale, which comprises performing the above-mentioned polymerization in a polymerization vessel in which a coating film containing at least one selected from the above is formed.

The production of a reaction product of tannins and aldehydes (hereinafter referred to simply as "reaction product"), which is the component (A) of the coating film,
For example, C.I. A98-35, 649q, Minoru Imoto "Adhesion"
383 to 386, No. 8 (1980), Japanese Patent Laid-Open No. 57-192414, and other highland methods. For example, it can be carried out by a reaction in which tannins and aldehydes are co-condensed in an aqueous medium or an organic solvent under a nitrogen atmosphere at 30 to 180 ° C. In this reaction, an acid such as hydrochloric acid, sulfuric acid or phosphoric acid can be used as a catalyst.

Examples of tannins used for producing the reaction product include tannic acid, quintuple tannin, gallic tannin,
Smack tannin, tara tannin, valonia tannin,
Hydrolyzable tannins such as chestnut tannins, myrobalan tannins, oak tannins, dividivitannins, argalovia tannins; gambier tannins, quebracho tannins, mimosa tannins, mangrove tannins,
Examples thereof include condensed tannins such as hemlock tannin, sprue stannin, burmacattaninine, oak bark tannin, and oyster astringent tannin. These may be used alone or in combination of two or more. Among these, tannic acid, quintuple tannin, gallic tannin, kebracho tannin, mimosa tannin, oak bark tannin, and oyster astringent tannin are preferable.

As the aldehydes used for producing the reaction product,
For example, aliphatic aldehydes such as formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, isobutyraldehyde, acrolein, crotonaldehyde, chloral; benzaldehyde, 2-methylbenzaldehyde, 3-methylbenzaldehyde,
Examples thereof include aromatic aldehydes such as 4-methylbenzaldehyde, 1,2-diformylbenzene, 1,3-diformylbenzene, and 1,4-diformylbenzene. These may be used alone or in combination of two or more. Among these, formaldehyde, acetaldehyde, acrolein, chloral, benzaldehyde,
1,2-diformylbenzene is preferred.

The ratio of tannins / aldehydes used in the production of the reaction product is usually 95/5 to 10/90, preferably 90/10 to 30/70, from the viewpoint of good yield of the reaction product.

The ester derivative of tannins (hereinafter referred to as "derivative"), which is the component (A) of the coating film, is obtained by adding an acid halide to tannins in an alkaline aqueous solution and heating them to react. . The tannins used are the same as those used to produce the reaction product.

Examples of the acid halide used for producing the derivative include formyl chloride, acetyl chloride, isobutyryl chloride, benzoyl chloride and the like. These may be used alone or in combination of two or more.

In the production of the derivative, the ratio of tannins / acid halides used is usually preferably 95/5 to 10/90, more preferably 90/10 to 30/70. If the amount of tannins used is too large or too small, the yield of the resulting derivative may decrease.

Examples of the alkaline aqueous solution used include aqueous solutions of alkaline substances such as sodium hydroxide and potassium hydroxide. The concentration of alkaline substances is usually
It is preferably 1 to 50% by weight, more preferably 5 to 30% by weight.

The reaction is usually at a temperature of 10 to 200 ° C., preferably 20 to 100 ° C., usually 0.1 to 24 hours, preferably about 0.5 to 10 hours,
It is carried out with stirring.

Examples of the dye and pigment that are the component (B) of the coating film include:
Azo dyes / pigments such as monoazo and polyazo dyes / pigments, metal complex salt azo dyes / pigments, stilbene azo dyes, thiazole azo dyes; anthraquinone dyes / pigments such as anthraquinone derivatives and anthrone derivatives; indigo dyes such as indigo derivatives and thioindigo derivatives.・ Pigment; Phthalocyanine dye / pigment; Carbonium dye / pigment such as diphenylmethane dye, triphenylmethane dye / pigment, xanthene dye, acridine dye; Quinoneimine dye such as azine dye, oxazine dye, thiazine dye; Methine such as polymethine or cyanine dye Dyes; quinoline dyes; nitro dyes; benzoquinone and naphthoquinone dyes; naphthalimide dyes and pigments; perinone dyes; sulfur dyes; fluorescent dyes; azoic dyes; and reactive dyes Come, it can also be used in more than one combination even alone. Among these dyes and pigments exemplified, azine dyes are particularly preferable. More specific examples of these dyes and pigments are as follows.

Examples of azo dyes and pigments include the following.

As monoazo and polyazo dyes, for example, Basic Yellow 32, 34 and 36; Basic Orange 2, 32, 33 and 34; Basic Red 17, 1
8, 22, 23, 24, 32, 34, 38, 39 and 40; Basic Violet 26 and 28; Basic Blue 58, 59, 64, 65, 66, 67 and 68; Basic Brown 1, 4, 11 and 12; Basic Black 8; Azoic Azo Components 4, 21, 27 and 38; Disperse Yellow 3,
4,5,7,8,23,50,60,64,66,7
1, 72, 76, 78 and 79; Disperse Orange 1, 3, 5, 13, 20, 21, 30, 32, 41,
43, 45, 46, 49, 50 and 51; Disperse Red 1, 5, 7, 12, 13, 17, 43, 52,
54, 56, 58, 60, 72, 73, 74, 75, 7
6,80,82,84,88,90,97,99,10
1, 103, 113, 117, 122, 125, 12
6,128 and 129; Disperse Violet 1
0, 24, 33, 38, 41, 43 and 96; Disperse Blue 85, 92, 94 and 106; Disperse Brown 3 and 5; Disperse Black 1,
2,10,26,27,28,29,30 and 31;
Solvent Yellow 2,6,14,15,16,19,
21 and 56; Solvent Orange 1, 2, 5, 6,
14 and 45; Solvent Red 1, 3, 23, 2
4, 25, 27 and 30; Solvent Brown 3, 5
And 20; Solvent Black 3; Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 1
3,14,15,16,17,23,65,73 and 83; Pigment Orange 1,2,5,13,14,1
5,16,17,24 and 31; Pigment Red 1,2,3,4,5,6,7,8,9,10,11,1
2,13,14,15,16,17,18,19,2
1, 22, 23, 30, 31, 32, 37, 38, 3
9, 40, 41, 48, 49, 50, 51, 52, 5
3,54,55,57,58,60,63,64,6
8, 112, 114 and 163; Pigment Blue 2
5: Pigment Green 10; Pigment Brown 1 and 2; Pigment Black 1; Direct Yellow 1, 8, 11, 12, 24, 26, 27, 28, 33,
44, 50, 58, 85, 86, 87, 88, 89, 9
8,100 and 110; Direct Orange 1,6
8, 10, 26, 29, 39, 41, 49, 51, 5
7, 102 and 107; Direct Red 1, 2,
4,13,17,20,23,24,28,31,3
3,37,39,43,46,62,63,75,7
9, 80, 81, 83, 84, 89, 95, 99, 11
3,197,201,218,220,224,22
5,226,227,228,229,230 and 2
31; Direct Violet 1, 7, 9, 12, 2
2,35,51,63,90,94 and 98; Direct Blue 1,2,6,8,15,22,25,71,
76, 77, 78, 80, 120, 123, 158, 1
60, 163, 165, 168, 192, 193, 19
4,195,196,203,207,225,23
6,237,246,248 and 249; Direct Greens 1,6,8,28,30,31,33,37,
59, 63, 64 and 74; Direct Brown 1
A, 2, 6, 25, 27, 44, 58, 59, 101,
106,173,194,195,209,210 and 211; Direct Black 17,19,22,3
2,38,51,56,71,74,75,77,9
4, 105, 106, 107, 108, 112, 11
3, 117, 118, 132, 133 and 146; Acid Yellow 11, 17, 19, 23, 25, 29,
36, 38, 40, 42, 44, 49, 61, 70, 7
2,75,76,78,79,110,127,13
1,135,141,142,164 and 165; Acid Orange 1,7,8,10,19,20,24,
28, 33, 41, 43, 45, 51, 56, 63, 6
4,65,67 and 95; Acid Red 1,6
8, 9, 13, 14, 18, 26, 27, 32, 35,
37, 42, 57, 77, 85, 88, 89, 97, 1
06,111,114,115,117,118,11
9,129,130,131,133,134,13
8,143,145,154,155,158,16
8,249,252,254,257,262,26
5,266,274,276,282,283 and 3
03; Acid Violet 7, 11, 97 and 10
6; Acid Blue 29, 60, 92, 113, 117
And 120; Acid Greens 19, 20 and 4
8; Acid Brown 2,4,13,14,20,5
3,92,100,101,236,247,266
268,276,277,282,289,301 and 302; Acid Black 1,7,24,26,2
9, 31, 44, 76, 77, 94, 109 and 11
0; Mordant Yellow 1, 3, 5, 23, 26, 3
0,38 and 59; Modant Orange 1,4,5,5
6,8,29 and 37; Mordant Red 7,9,1
7, 19, 21, 26, 30, 63 and 89; Mordant Violet 5 and 44; Mordant Blue 7,
13,44,75 and 76; Mordant Green 1
1,15,17 and 47; Mordant Brown 1,1
4,15,19,21,33,38,40,52 and 87; Modant Black 1,3,7,9,11,1
7, 26, 32, 38, 43, 44, 51, 54, 6
5,75,77,84,85,86 and 87; Food Yellow 3 and 4; Food Red 7 and 9; As metal complex azo dyes, for example, Solvent Yellow 61 and 80; Solvent Orange 37, 40 and 44; Solvent Red 8, 21,
83, 84, 100, 109 and 121; Solvent Brown 37; Solvent Black 23; Acid Black 51, 52, 58, 60, 62, 63, 64, 6
7, 72, 107, 108, 112, 115, 118,
119, 121, 122, 123, 131, 132, 1
39, 140, 155, 156, 157, 158, 15
9 and 191; Acid Yellow 59, 98, 99,
111, 112, 114, 116, 118, 119, 1
28, 161, 162 and 163; Acid Orange 74, 80, 82, 85, 86, 87, 88, 122,
123 and 124; Acid Red 180,183,
184, 186, 194, 198, 199, 209, 2
11,215,216,217,219,256,31
7,318,320,321 and 322; Acid Violet 75 and 78; Acid Blue 151,1
54, 158, 161, 166, 167, 168, 17
0,171,175,184,187,192,19
9,229,234 and 236; Acid Green 7,12,35,43,56,57,60,61,6
5, 73, 75, 76, 78 and 79; Acid Brown 19, 28, 30, 31, 39, 44, 45, 4
6,48,224,225,226,231,256,
257, 294, 295, 296, 297, 299 and 300; Direct Yellow 39; Direct Violet 47 and 48; Direct Blue 90, 98,
200, 201, 202 and 226; Direct Brown 95, 100, 112 and 170; Examples of stilbene azo dyes include Direct Black 62; Examples of thiazole azo dyes include Direct Red 9 and 11.

Examples of the anthraquinone dye / pigment include the following.

Examples of the anthraquinone derivative include Basic Vio Red 25; Basic Blue 21,
22, 44, 45, 47, 54 and 60; Azoic diazo component 36; Bat Yellow 2, 3, 1
0, 20, 22 and 33; bat orange 13 and 15; bat red 10, 13, 16, 31, 35 and 52; bat violet 13 and 21; bat blue 4, 6, 8, 12, 14, 64, 66, 67 and 72; Bat Greens 8, 13, 43, 44 and 4
5; Bat Brown 1, 3, 22, 25, 39, 41,
44, 46, 57, 68, 72 and 73; Bat Black 8, 14, 20, 25, 27, 36, 56, 59 and 60; Disperse Orange 11; Disperse Red 4, 9, 11, 15, 53, 55, 65, 91, 9
2,100,104,116 and 127; Disperse Violet 1,4,8,23,26,28,30 and 37; Disperse Blue 1,3,5,6,7,2
0, 26, 27, 54, 55, 56, 60, 61, 6
2, 64, 72, 73, 75, 79, 81, 87, 9
0, 91, 97, 98, 99, 103, 104 and 1
05; Disperse Yellow 51; Solvent Violet 13 and 14; Solvent Blue 11, 12, 3
5 and 36; Solvent Green 3; Pigment Red 83 and 89; Pigment Blue 22; Acid Violet 31, 34, 35, 41, 43, 47, 4
8, 51, 54, 66 and 68; Acid Blue 2
3,25,27,40,41,43,45,54,6
2, 72, 78, 80, 82, 112, 126, 12
7,129,130,131,138,140,14
2,143,182,183,203,204 and 2
05; Acid Green 25, 27, 28, 36, 4
0, 41 and 44; Acid Brown 27; Acid Black 48 and 50; Mordant Red 3 and 1
1; modant blue 8 and 48; modant black 13; pigment violet 5; as anthrone derivative, for example, bat yellow 1 and 4; bat orange 1, 2,
3, 4 and 9; Bat Violet 1, 9 and 1
0; Bat blue 18, 19 and 20; Bat green 1, 2, 3 and 9; Bat black 9, 13, 29
And 57; bat red 13; acid red 80,
82 and 83.

Examples of the indigoid dye / pigment include the following.

As indigo derivatives, for example, bat blue 1, 3, 5, 35 and 41; reduced bat blue 1; pigment violet 19 and 122; acid blue 74 and 102; solubilized bat blue 5 and 41; solubilize De Butt Black 1; Food Blue 1; Examples of thioindigo derivatives include Butt Orange 5; Butt Reds 1, 2 and 61; Butt Violet 2 and 3; Pigment Red 87 and 88; Butt Brown 3.

Examples of the phthalocyanine dye / pigment include Solvent Blue 55; Pigment Blue 15, 16 and 17;
Pigment Green 36, 37 and 38; Direct Blue 86 and 199; Modant Blue 58.

Examples of the carbonium dye / pigment include the following.

Examples of the diphenylmethane dye include Basic Red 9; Basic Violet 1, 3 and 14; Basic Blue 1, 5, 7, 19, 26,
28, 29, 40 and 41; Basic Green 1 and 4; Solvent Violet 8; Solvent Blue 2 and 73; Pigment Violet 3; Pigment Blue 1, 2 and 3; Pigment Green 1, 2 and 7; Direct Blue 41; Acid Violet 1
5 and 49; Acid Blue 1,7,9,15,2
2, 83, 90, 93, 100, 103 and 104;
Acid Green 3, 9 and 16; Mordant Violet 1; Mordant Blue 1, 29 and 47; Food Violet 2; Food Blue 2; Food Green 2; As a xanthene dye, for example, Basic Red 1; Solvent Red 49; Pigment Red 81 and 90; Pigment Violet 1,
2 and 23; Acid Red 51, 52, 87, 92
And 94; Modant Red 15 and 27; Food Red 14; Examples of acridine dyes include Basic Orange 14 and 15.

The quinone imine dyes include the following.

As an azine dye, for example, Basic Red 2; Basic Black 2; Solvent Black 5 and 7; Acid Blue 59; Acid Black 2; As an oxazine dye, for example, Basic Blue 3; Direct Blue 106 and 1
08: Examples of thiazine dyes include Basic Yellow 1; Basic Blue 9, 24 and 25.

The following are mentioned as a methine dye.

As the polymethine (or cyanine) dye, for example, Basic Yellow 11, 13, 14, 19, 21, 2
5, 28, 33 and 35; Basic Orange 21 and 22; Basic Red 12, 13, 14, 15,
27, 29, 35, 36 and 37; Basic Violet 7, 15, 21 and 27.

Examples of quinoline dyes include Basic Green 6; Disperse Yellow 54 and 56; Solvent Yellow 33; Acid Yellow 3
Is mentioned.

Examples of the nitro dye include Disperse Yellow 1, 33, 39, 42, 49 and 54; Acid Yellow 1.

Examples of the benzoquinone and naphthoquinone dyes include Disperse Blue 58 and 108; Acid Brown 103, 104, 106, 160, 161, 165 and 188.

Examples of the naphthalimide dye / pigment include Pigment Red 123; Vat Violet 23 and 29; Acid Yellow 7.

Examples of the sulfur dye include Solubilised Sulfur Yellow 2; Sulfur Yellow 4; Sulfur Orange 3; Sulfur Red 2, 3, 5 and 7; Solubilized Sulfur Blue 15; Sulfur Blue 2, 3, 4 , 6, 7, 9
And 13; Sulfur Greens 2, 3, 6, 14 and 27; Solubilised Sulfur Browns 1 and 51; Sulfur Browns 7, 12, 15 and 3
1; Sulfur Black 1, 2, 5, 6, 10, 11 and 15; Vat Yellow 35, 42 and 43; Vat Blue 43 and 56.

Examples of fluorescent dyes include Fluorescent Brightening Agent 14,
22, 24, 30, 32, 37, 45, 52, 54, 5
5,56,84,85,86,87,90,91,10
4,112,121,134,135,153,16
2,163,164,166,167,168,16
9,170,171,172,173,174,17
5,176 and 177.

Examples of azoic dyes include azoic diazo components 17, 20, 22, 2
4, 26, 31, 35, 41, 47, 48, 109 and 121; Azoic coupling components 2,
3, 4, 5, 7, 8, 10, 11, 12, 14, 15,
16, 17, 18, 19, 20, 23, 26, 28, 2
9, 35, 36, 37, 41 and 108; Azoic Browns 2, 7, 11 and 15; Azoic Blacks 1 and 5; Azoic Yellows 1 and 2; Azoic Oranges 2, 3 and 7; Azoic Red 1 , 2,
6, 9, 16 and 24; Azoic Violet 1,
2, 6, 7, 9 and 10; azoic green 1.

As the reactive dye, for example, reactive yellow 1, 2, 3, 4, 6, 7, 11,
12, 13, 14, 15, 16, 17, 18, 22, 2
3,24,25,26,27,37 and 42; Reactive Orange 1,2,4,5,7,13,14,1
5,16,18,20,23 and 24; Reactive Red 1,2,3,4,5,6,7,8,11,12,
13,15,16,17,19,20,21,22,2
3,24,28,29,31,32,33,34,3
5,36,37,38,39,40,41,42,4
3,45,46,49,50,58,59,63 and 64; Reactive Violet 1,2,4,5,8,
9 and 10; Reactive Blue 1, 2, 3, 4,
5,7,8,9,13,14,15,17,18,1
9, 20, 21, 25, 26, 27, 28, 29, 3
1, 32, 33, 34, 37, 38, 39, 40, 4
1,43,44 and 46; Reactive Green 5,
6, 7 and 8; Reactive Brown 1, 2, 5,
7,8,9,10,11,14 and 16; Reactive Black 1,3,4,5,6,8,9,10,12,
13, 14 and 18.

Furthermore, examples of the pigment include inorganic pigments such as chrome yellow, zinc yellow, ZTO type zinc chromate, red lead, iron oxide powder, zinc white, aluminum powder and zinc dust.

In the method of the present invention, the coating film formed on the inner wall surface of the polymerization vessel, the inner wall surface of the polymerization vessel is a coating solution prepared by dissolving or dispersing the components (A) and (B) in a suitable solvent. And the like. The total concentration of the components (A) and (B) in the coating liquid is not particularly limited as long as the coating amount described below can be obtained, but is usually 0.005 to 10% by weight, preferably 0.01 to 5% by weight. Further, the content ratio of each component in the coating liquid,
In terms of good scale prevention effect, usually (A) component 100
0.1 to 1000 parts by weight of component (B), preferably 1 part by weight
~ 600 parts by weight.

Examples of the solvent used for preparing the coating liquid include water;
Methanol, ethanol, propanol, butanol,
Alcohol solvents such as 2-butanol, 2-methyl-1 propanol, 2-methyl-2-propanol, 3-methyl-1-butanol, 2-methyl-2-butanol, 2-pentanol; acetone, methyl ethyl ketone,
Ketone solvents such as methyl isobutyl ketone; ester solvents such as methyl formate, ethyl formate, methyl acetate, methyl acetoacetate; ether solvents such as 4-methyldioxolane, ethylene glycol diethyl ether, 1,4-dioxane; tetrahydrofuran, etc. And aprotic solvents such as dimethylformamide, dimethylsulfoxide, acetonitrile and the like, and these are appropriately used alone or as a mixed solvent of two or more kinds.

In the method of the present invention, in order to form a coating film for preventing the adhesion of polymer scale on the inner wall surface of the polymerization vessel, the inner wall surface of the polymerization vessel and a coating solution containing the above components (A) and (B), Preferably, it may be applied to other portions with which the monomer comes into contact during the polymerization, such as a stirring shaft and a stirring blade, and then sufficiently dried at a temperature of room temperature to about 100 ° C. Further, the coating solution may be applied after heating the inner wall of the polymerization vessel and the portion in contact with other monomers in advance (to about 30 to 80 ° C.). In either case, the coating surface can be sufficiently dried and then washed with water as needed to obtain a coating film.

The coating film obtained as described above, the total coating amount of the component (A) and the component (B) is usually 0.005 to 5 g / m ² or more, particularly 0.05.
It is preferably ˜2 g / m ² .

In the present invention, the above-mentioned work of forming a coating film may be carried out for each batch of polymerization, but since the formed coating film has considerable durability and the scale preventing action is connected, it is not always necessary for each batch. It is not necessary to carry out the above procedure, and usually, it may be carried out 1 to 10 times for each batch.

In this way, after the coating treatment is completed on the inner wall of the polymerization vessel and other portions where the monomer contacts during the polymerization, the monomer having an ethylenic double bond and the polymerization initiator are added to the polymerization vessel according to a conventional method. In addition, other necessary polymerization medium and additives such as a dispersion aid of a monomer may be charged and polymerized.

As the monomer having an ethylenic double bond to which the method of the present invention is applied, for example, vinyl halide such as vinyl chloride, vinyl acetate, vinyl ester such as vinyl propionate, acrylic acid, methacrylic acid or their Examples thereof include esters or salts, maleic acid or fumaric acid, and their esters or anhydrides, diene-based monomers such as butadiene, chloroprene and isoprene, and styrene, acrylonitrile, vinylidene halide, vinyl ether and the like.

Further, the type of polymerization to which the method of the present invention is applied is not particularly limited, and is effective in any type of polymerization such as suspension polymerization, emulsion polymerization, bulk polymerization and gas phase polymerization.

Therefore, as the additive substance to be added to the polymerization system, those usually used can be used without any restrictions. That is,
For example, t-butyl peroxyneodecanate, di-2
-Ethylhexyl peroxydicarbonate, 3,5
5-trimethylhexanoel peroxide, α-cumylperoxy neodecanoate, cumene hydroperoxide, cyclohexanone peroxide, t-butylperoxypivalate, di-2-ethoxyethylperoxydicarbonate, benzoyl peroxide, Lauroyl peroxide, 2,4-dichlorobenzoyl peroxide, diisopropyl peroxydicarbonate, α, α′-azobisisobutyronitrile, α,
Polymerization catalysts such as α'-azobis-2,4-dimethylvaleronitrile, potassium persulfate, ammonium persulfate and p-menthane hydroperoxide; partial oxides of polyvinyl acetate, polyacrylic acid, vinyl acetate and maleic anhydride Suspending agents such as copolymers, cellulose derivatives such as hydroxypropylmethyl cellulose, natural or synthetic polymer compounds such as gelatin; solid dispersants such as calcium phosphate and hydroxyapatite; sorbitan monolaurate, sorbitan trioleate, polyoxyethylene alkyl Nonionic emulsifiers such as ethers; sodium alkylbenzene sulfonates such as sodium lauryl sulfate and sodium dodecylbenzene sulfonate; anionic emulsifiers such as sodium dioctyl sulfosuccinate; calcium carbonate, oxidation Fillers such as Tan; tribasic lead sulfate,
Calcium stearate, dibutyltin dilaurate,
Stabilizers such as dioctyltin mercaptide; lubricants such as rice wax, stearic acid and cetyl alcohol; DO
Even in a polymerization system in which a plasticizer such as P or DBP, a chain transfer agent such as trichloroethylene or a mercaptan, and a pH adjusting agent are present, the method of the present invention can effectively prevent the adhesion of polymer scale.

〔Example〕

Next, the method of the present invention will be described with reference to Examples and Comparative Examples. In addition, in each of the following tables, the experiment numbers marked with * are comparative examples, and the other experiment numbers are examples of the present invention.

Example of production of reaction product of tannins and aldehydes (1) Production of reaction product No. 1 70 g of tannins, 25 g of 37% formalin solution and methanol
80 g were mixed and reacted at 75 ° C. for 2 hours with stirring. The reaction mixture obtained was dried under reduced pressure to give the reaction product N
90 g of o.1 was obtained.

(2) Production of reaction product No. 2 Kebrachotannin 50 g, 35% hydrochloric acid 3 g, chloral 10
g and 100 g of water were mixed and reacted at 100 ° C. for 3 hours while stirring. The obtained reaction mixture was dried under reduced pressure to obtain 60 g of a reaction product No. 2.

(3) Production of reaction product No. 3 Tannic acid 100 g, benzaldehyde 20 g, phosphoric acid 50
g and 400 g of water were mixed and reacted at 120 ° C. for 6 hours. The obtained reaction mixture was filtered, washed with hot water 5 to 6 times to remove excess phosphoric acid, and then dried to give a reaction product No. 3 70
g was obtained.

Production Example of Ester Derivative of Tannins (1) Production of Derivative No. 1 After dissolving 30 g of tannic acid in 300 g of water, 30 g of benzoyl chloride was added. Next, 25% 20% aqueous potassium hydroxide solution
g was added, and the mixture was reacted at 30 ° C. for 1 hour with stirring.

The obtained reaction mixture was filtered, washed with water 5 to 6 times, and then dried to obtain 45 g of derivative No. 1.

(2) Production of derivative No. 2 40 g of oyster astringent tannin was dissolved in 300 g of water, and 10 g of acetyl chloride was added. Next, 20% potassium hydroxide aqueous solution
20 g was added and reacted at 30 ° C. for 1 hour while stirring.

The obtained reaction mixture was filtered, washed with water 5 to 6 times and then dried to obtain 47 g of derivative No. 2.

(3) Production of derivative No. 3 After dissolving 30 g of gallic tannin in 300 g of water, 20 g of benzoyl chloride was added. Next, 20 g of 20% aqueous sodium hydroxide solution was added, and the reaction was carried out at 50 ° C. for 0.5 hours with stirring.

The obtained reaction mixture was filtered, washed with water 5 to 6 times and then dried to obtain 40 g of derivative No. 3.

Example 1 Polymerization was carried out as follows using a stainless steel polymerization vessel with an internal volume of 100 and equipped with a stirrer.

In each experiment, first, as shown in Table 1, the components (A) and (B) were dissolved in a solvent to prepare a coating solution with a total concentration of 0.5% by weight. It was applied to the part where the monomer was in contact with, heated at 50 ° C. for 15 minutes, dried, and washed with water. However, Experiment Nos. 1 to 4 are comparative examples in which the coating liquid was not applied or the coating liquid containing only one of the component (A) and the component (B) was applied. Used in each experiment
Table 1 shows the components (A) and (B), the weight ratio of (A) / (B) and the solvent used.

Then, 40 kg of water, 17 kg of vinyl chloride, 4 kg of vinyl acetate, 12 g of partially saponified polyvinyl alcohol, 4 g of hydroxypropylmethylcellulose, 200 g of trichloroethylene and α, α′- 0.5 kg of dimethylvaleronitrile was charged, and polymerization was carried out at 58 ° C. for 6 hours while stirring. After completion of the polymerization, the amount of polymer scale attached to the inner wall surface of the polymerization vessel was measured. The results are shown in Table 1.

Example 2 Polymerization was carried out as follows using a stainless steel polymerization vessel with an internal volume of 20 and equipped with a stirrer.

In each experiment, first, the components (A) and (B) shown in Table 2 were dissolved in a solvent to prepare a coating solution having a total concentration of 0.2% by weight. The solution was applied to the part in contact with the polymer, heated at 40 ° C for 15 minutes, dried, and washed with water. However, Experiment Nos. 16 to 19 are comparative examples in which the coating liquid was not applied or the coating liquid containing only one of the component (A) and the component (B) was applied. Table 2 shows the components (A) and (B) used in each experiment, the weight ratio of (A) / (B) and the solvent used.

Then, 26 kg of polybutadiene latex (solid content concentration: 45% by weight), 8 kg of pure water, 100 g of sodium oleate, 1.8 kg of styrene, 1 kg of acrylonitrile, t- Charge 8 g of dodecyl mercaptan and 28 g of cumene hydroperoxide, raise the internal temperature to 65 ° C, then charge 40 g of glucose, 0.4 g of ferrous sulfate and 20 g of sodium pyrophosphate, and stir at 65 ° C for 5 hours. Polymerized. After completion of the polymerization, the amount of polymer scale attached to the inner wall surface of the polymerization vessel was measured. The results are shown in Table 2.

[Effect of the Invention] According to the method of the present invention, it is possible to always and effectively prevent the adhesion of the polymer scale regardless of various polymerization conditions such as the type of the monomer used. For example, it is possible to effectively prevent the polymer scale from adhering to the inner wall surface of the polymerization vessel or the like in the polymerization of a monomer having an ethylenic double bond, which has been difficult in the past. In the method of the present invention, the coating liquid is applied once every batch or several batches to form a coating film, so that the polymerization vessel can be repeatedly used without adhering the polymer scale.

Claims (1)

[Claims] 1. A method for preventing adhesion of a polymer scale in the polymerization of a monomer having an ethylenic double bond in a polymerization vessel, wherein (A) tannins and aldehyde are previously formed on the inner wall surface of the polymerization vessel. Polymerization is carried out in a polymerization vessel formed with a coating film containing at least one selected from the group consisting of a reaction product of a class of compounds and an ester derivative of a tannin, and (B) at least one selected from a dye and a pigment. A method for preventing adhesion of polymer scale, which comprises: