JPS6144939A - Vinyl chloride polymer composition - Google Patents

Abstract

PURPOSE:The titled composition which can give a low-viscosity plastisol of a reduced viscosity change with time and give a molding of good heat stability, prepared by mixing a vinyl chloride polymer with a specified alkylphenyl ether sulfonate compound. CONSTITUTION:100pts.wt. vinyl chloride polymer comprising vinyl chloride and 0-30wt% monomer copolymerizable therewith (e.g., ethylene) is mixed with 0.1-5pts.wt. alkylphenyl ether sulfonate compound of formula I (wherein R is a 6-18C alkyl, n is 0-4, X is a group of formula II or -CH2-CH2-, and M is an alkali metal or ammonium), a plasticizer (e.g., dioctyl phthalate), a stabilizer, etc.

Description

Detailed Description of the Invention "Industrial Application Field" The present invention provides a plastisol with low viscosity and little change in viscosity over time, and the use of polyvinyl chloride, which makes it possible to obtain molded products with excellent thermal stability. The present invention relates to a polymer composition.

``Prior art'' Vinyl chloride polymers for pastes are produced by mechanically dissolving vinyl chloride in water uniformly and finely using an emulsion polymerization method using a water-soluble polymerization catalyst or using a so-called oil-soluble catalyst that dissolves in vinyl chloride. It is produced by a fine suspension polymerization method, in which it is dispersed (homogenized) in water and then polymerized. At this time, anionic surfactants such as alkyl alcohol sulfate salts, alkyl sulfonate salts, and alarlyl sulfonate salts are used as emulsifiers. The vinyl chloride polymer for paste obtained in this way has a high initial viscosity, for example, in a best dispersion such as plastisol or organosol prepared by blending the polymer with a plasticizer, diluent, stabilizer, etc. Moreover, the sol viscosity increases orally, and even if the initial viscosity is low, the sol viscosity increases after a few days, making molding difficult. Furthermore, molded articles obtained from the polymer also had the disadvantage of poor thermal stability.

Therefore, for the purpose of reducing sol viscosity, etc., the above-mentioned anionic surfactants, polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene block copolymer, sorbitan ester, etc. are added to the latex after polymerization.
A method for producing a vinyl chloride polymer for paste in which an appropriate amount of one or more nonionic surfactants such as glycerin alkyl ester is added and dried, or the above-mentioned surfactants may be added at the time of sol preparation. It is being said. However, such general methods do not necessarily yield satisfactory results in terms of viscosity reduction and thermal stability.

On the other hand, alkyl sulfate esters are used as emulsifiers when producing vinyl chloride polymers for pastes in order to improve the state of foam cells of vinyl chloride paste sol, high expansion ratio, processing temperature range, and foaming properties with low plasticizer formulations. Alternatively, a method using an alkali metal salt or ammonium salt of an ethoxylated alkyl sulfate is described in Tokkosho, t/-, 2/J7.
! It is publicly known in the publication No. However, the vinyl chloride polymer for paste produced by this method has a large increase in sol viscosity over time, and for the purpose of producing or blending a vinyl chloride resin composition for paste that can provide thermal stability of molded products, The use of an alkali metal salt or ammonium salt of polyoxyethylene alkylphenol ether sulfate as an emulsifier was published in JP-A-Shojter 10! It is disclosed in the publication No. Similar to the above-mentioned ethoxylated alkyl sulfate, the vinyl chloride resin composition for paste using this emulsifier also shows large changes in viscosity over time and has poor thermal stability.

The present inventor has developed a vinyl chloride polymer that does not have the above-mentioned conventional drawbacks, that is, can provide a plastisol with low viscosity and little change in viscosity upon oral administration, and can also yield molded products with good thermal stability. As a result of careful consideration of the composition,
The present inventors have discovered that the objects of the present invention can be achieved by incorporating a specific sulfonate compound into a vinyl chloride polymer, and have completed the present invention.

That is, an object of the present invention is to provide a vinyl chloride polymer composition that provides a plastisol that has a low initial viscosity and a small change in oral viscosity, and that also allows molded articles with excellent thermal stability to be obtained.

However, the gist of the present invention is that 100 parts of a vinyl chloride polymer is mixed with the general formula (1) (where R is the number of carbon atoms t~/which alkyl group n is an integer of θ~≠). X is -OHg -0H-CH- or -〇H, -OH
The group M represented by H represents an alkali metal atom or an ammonium group, respectively. ) A vinyl chloride polymer composition containing 0.1 to 1 part by weight of an alkylphenyl ether sulfonate compound represented by:

To explain the present invention in detail, the vinyl chloride polymer used in the composition of the present invention is a vinyl chloride homopolymer or vinyl chloride and other monomers copolymerizable therewith, such as ethylene, propylene, n- Olefins such as butene, vinyl acetate, vinyl esters, vinyl esters such as vinyl stearate, unsaturated acids such as acrylic acid, methacrylic acid, itaconic acid or their alkyl esters, methyl vinyl ether, ethyl vinyl ether ,
Examples include octyl vinyl ether, lauryl vinyl ether, unavinyl ether, maleic acid, fumaric acid or their anhydrides or esters, aromatic vinyl, unsaturated nitrile, etc., or copolymers with monomers such as l'la or two or more. It will be done. Monomers that can be copolymerized with vinyl chloride are
In the case of a copolymer, the content of the copolymerizable monomer is not more than 30% by weight of the copolymer, preferably not more than 20% by weight of the copolymer. Desirably, although not particularly limited, in the present invention, whose main purpose is to reduce the viscosity of plastisol and to minimize changes in viscosity over time, it is desirable that the plastisol be obtained by emulsion polymerization or fine suspension polymerization.

The alkylphenyl ether sulfonate compound represented by the general formula [I] which is one component of the composition of the present invention is:
R in the formula is a fatty acid hydrocarbon group having a carbon atom number of t to /r, and the aliphatic hydrocarbon group is preferably a straight chain, usually at the para-position with respect to the oxygen atom bonded to the benzene ring. There are many things. n is an integer of O-Hiro, particularly preferably in the range of 1 to 3. The sulfonate compound is
For example, alkali metal salts or acid ammonium salts of alkylphenyl-2-sulfoethyl ether, alkali metal salts or ammonium salts of alkylphenyl-3-sulfo-hydroxypropylethyl, alkali alkylphenyl polyoxyethylene-cosulfoethyl ethers, etc. Examples include metal salts or ammonium salts, alkali metal salts or ammonium salts of alkylphenylpolyoxyethylene-3-sulfo-hydroxypropyl ether, and the like. The sulfonate compound is preferably contained in an amount of 0.47 to 5 parts by weight, preferably 0.3 to 3 parts by weight, particularly 0.3 to 1 part by weight, based on 100 parts by weight of the vinyl chloride polymer. .

In order to incorporate the alkylphenyl ether sulfonate compound represented by the general formula [I] into the vinyl chloride polymer, the following various methods can be employed, for example.

(1) During emulsion polymerization or fine suspension polymerization, the sulfonate compound is present as an emulsifier or auxiliary emulsifier, and the resulting vinyl chloride polymer latex is directly spray-dried.

(2) The sulfonate compound is added as a dispersant (adjusting emulsifier) to a vinyl chloride polymer latex obtained by emulsion polymerization or fine suspension polymerization, and the latex is spray-dried.

(3) When preparing plastisol by adding a plasticizer, stabilizer, etc. from a vinyl chloride polymer obtained by emulsion polymerization or fine suspension polymerization, the sulfonate compound is added as a viscosity reducing agent.

(4) It is added when the vinyl chloride polymer produced by suspension polymerization is triblended with a plasticizer and the like.

Of course, the method for incorporating the sulfonate compound into the vinyl chloride polymer is not limited to the method described above, and various modified methods may be adopted. Preferably, those prepared by the method 3) are prepared, and in particular those prepared by emulsion polymerization or spray drying of a finely suspended vinyl chloride polymer latex containing a sulfonate compound, as in (1) and (2). This is a preferred embodiment in terms of composition production and sol adjustment.

"Effects of the Invention" The vinyl chloride polymer of the present invention can be obtained by adding an alkylphenyl ether sulfonate compound represented by the general formula CI as an emulsifier during emulsion polymerization or fine suspension polymerization. It acts to uniformly emulsify or disperse a monomer such as vinyl chloride, has a favorable effect on the progress of polymerization, and can prevent the polymer from adhering to the can wall. Vinyl chloride polymer latex that has been subjected to emulsion polymerization or fine suspension polymerization is prepared by adding a sulfonate compound as an emulsifier during polymerization, or adding it after polymerization to improve dispersibility. After upgrading, the composition of the present invention can be obtained by simply spray drying, which is extremely advantageous economically and operationally.

In the composition of the present invention, when the vinyl chloride polymer is produced by emulsion polymerization or fine suspension polymerization and is in the form of a round product,
The viscosity of the plastisol prepared from the composition is initially low and changes little over time;
The plastisol has excellent fluidity due to its low viscosity not only in the low shear rate area but also in the high shear rate area, and this effect is particularly desired in the field of plastisol processing using coating methods. be.

For example, low sol viscosity in the low shear rate range facilitates handling of the paste sol, e.g. feeding, pouring, defoaming.
The low sol viscosity in the high shear rate range is a desirable property for the production of flooring, wall coverings, etc., as it allows high application rates.

Molded articles obtained from the composition of the present invention have excellent thermal stability. Therefore, in addition to being used as a vinyl chloride polymer composition for paste, the composition of the present invention can also be used in the Engel process, Heisler process, Hayashi process, etc.
As a vinyl chloride composition for powder molding such as dynamic dipping coating, electrostatic powder coating, and rotational molding, it is also a gel of round cyclized vinyl polymer produced by suspension polymerization because of its excellent thermal stability. It can be used as a composition for a temperature modifier.

"Examples" Next, the composition of the present invention will be explained in more detail in Examples, but the present invention is not limited to the following Examples as long as the gist thereof is not exceeded.

Note that "part" and "ch" described in the examples are based on weight.

The formulation of plastisol used in the test was as follows.

Vinyl chloride polymer composition 100 parts dioctyl phthalate) 40 parts Oa-Zn stabilizer
The test method for each of the three parts is as follows.

Type B viscosity (centiboise) Using a BE type viscometer (Tokyo Keiki Seisaku Rupture) 4x rotor,! It was measured at the rotational speed of Or, p, and m at -3°C. however,
A formulation was used in which the stabilizer was removed from the above formulation system.

Thermal Stability A sheet of ltm thickness that had been gelled at 19°C for 3 minutes was taken out every 5 minutes at 5°C, and the time until it turned dark brown was measured.

Example/Comparative Example 11λ 1rO of ion-exchanged water was placed in a θ01-volume polymerization tank equipped with a stirrer.
11.1 kg of vinyl chloride polymer seed latex with an average particle size of 0.2μ (emulsifier nilauryl sodium sulfate, catalyst persulfate potassium-sodium bisulfite system used) as polymer seeds.
After charging, it was degassed and 71.2 kg of vinyl chloride was added.

After raising the temperature to 50℃, the total amount was 0.0j% (
A redox catalyst of hydrogen peroxide-sodium formaldehyde sulfoxylate (vs. vinyl chloride) was added continuously. Furthermore, from the time when the polymerization rate reached 10% of the total amount of polymer seeds and vinyl chloride until the end of the polymerization, sodium lauryl sulfate was added as an emulsifier in an aqueous solution of about t to vinyl chloride at 0, θr per hour. It was added continuously at a rate of .

From the saturation pressure of vinyl chloride at a polymerization pressure of 10°C/k
y/-, the polymerization was stopped and unreacted monomers were collected. The average particle size of the obtained latex particles is
o, rμ. Divide the latex into three parts, part 2')
The sulfonate compounds and sodium dodecyl sulfate preparation emulsifiers shown in Table 1 were added to each polymer at 90°C.
After adding o and j%, the mixture was spray-dried, and then pulverized to obtain a vinyl chloride polymer.

The sol viscosity changes over time and thermal stability of plastisols prepared using these polymers were measured and are listed in Table 1.

Example C, Comparative Example 3 The vinyl chloride polymer produced in Comparative Example C (without emulsifier for adjustment) was added with the sulfonate compounds shown in Table 2 and 2
Uryl sodium sulfate OJ% (relative to vinyl chloride polymer) K
, was added to prepare plastisol. Oral changes in sol viscosity and thermal stability were measured and are also listed in Table 1.

Example 3: Micro-seeding fine suspension polymerization method Ion-exchanged water LOOO*1. lauroyl peroxide (hereinafter referred to as LPO) toof, lauryl sulfate soda go o o y,
Lauryl alcohol co.

After adding f, the premix tank was degassed, 40 kg of vinyl chloride monomer was added, and the mixture was maintained at Jt° C. without stirring. After stirring uniformly, the mixture was dispersed into a desired droplet size using a porous machine and transferred to a 2001 volume reaction tank equipped with a stirrer, which had been previously degassed. After the transfer of the dispersion liquid was completed, the temperature of the reaction tank was raised and polymerization was carried out by a known method. The emulsifying pressure of the emulsifying machine,
2! The average particle diameter of the seed polymer particles in the latex obtained by Okg/cfIIK is 0. It became ≠〃.

Next, the seed polymer particles were held at 10°C for 2 hours to decompose the excess LPO and reduce the amount of LPO contained in the core particles in order to produce a vinyl chloride polymer with an average particle size of lμ. It was adjusted.

Seed polymerization was performed using the seed polymer prepared as described above.

Add ion-exchanged water rO to a λoot volume polymerization tank equipped with a stirrer.
kg, average adjusted for I and PO amount above.

Seed latex with particle size O, Uμ as seed polymer≠
, Akg, sodium bicarbonate, 202, and then carefully prepared vinyl chloride monomer 7! , 4 A kg were charged, and the temperature was raised to Q° C., and then a 0.3 aqueous solution of sodium bisulfite, which had been dissolved in advance, was continuously added little by little to the polymerization tank to start polymerization. After starting the continuous addition of sodium bisulfite, the reaction was maintained at a constant rate.

Furthermore, the polymerization rate is 10% of the total amount of seed polymer and vinyl chloride.
From the time when IIC was reached until the end of the polymerization, the emulsifier shown in Table 3 was continuously added as an aqueous solution of about r% to the chloride and nil monomers at a rate of 0.0♂-/hour. The amount of gold added to the emulsifier was 0.s% based on vinyl chloride. The polymerization pressure decreased from the saturation pressure of vinyl chloride at 10°C to /kg, /(-J, and the polymerization was stopped during running and unreacted monomers were collected.Even if the emulsifier was different, the average particle size of the latex obtained was i, o~/, 1174!μ in sb
A lateated vinyl polymer was obtained. The emulsifier contained in the polymer was approximately o.s.%. Plastisol prepared using this polymer was measured for sol viscosity change over time and thermal stability using the above test method. The results are shown in Table 3.

Comparative Example ≠, j Using the seed polymer latex produced in Example 3, seed polymerization was conducted in the same manner as in Example 3 using various emulsifiers listed in Table 3 to produce a vinyl chloride polymer. . The viscosity and thermal stability of plastisols of these polymers were measured and are also listed in Table 3.

Claims (3)

[Claims] (1) To 100 parts by weight of vinyl chloride polymer, add the general formula [
I 〕 ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼…………〔 I 〕 (In the formula, R is an alkyl group having 6 to 18 carbon atoms. There is ▼ or -CH_
A group represented by 2-CH_2-, M represents an alkali metal atom or an ammonium group, respectively. ) A vinyl chloride polymer composition containing 0.1 to 5 parts by weight of an alkylphenyl ether sulfonate compound represented by: (2) The chloride according to claim 1, wherein the sulfonate compound represented by the general formula [I] is an alkali metal salt or ammonium salt of P-octylphenyldioxyethylene-3-sulfo-2-hydroxypropyl ether. Vinyl polymer composition. (3) The vinyl chloride system according to claim 1, wherein the sulfonate compound represented by the general formula [I] is an alkali metal salt or ammonium salt of P-octylphenyldioxyethylene-2-sulfoethyl ether. Polymer composition.