JPS6284103A - Production of chlorinated vinyl chloride resin forming transparent solution at low viscosity - Google Patents

Abstract

PURPOSE:To obtain the titled chlorinated vinyl chloride resin, by copolymerizing vinyl chloride with an alpha-olein in an aqueous medium using only a cellulosic derivative as a dispersion medium and chlorinating the resultant resin. CONSTITUTION:Vinyl chloride and an alpha-olefin, e.g. ethylene, are dispersed in an aqueous medium containing preferably 0.01-0.2pt.wt., based on the monomers to be polymerized, only substantially cellulosic derivative, e.g. methyl cellulose or hydroxypropyl methyl cellulose, present as a dispersion medium and copolymerized in the presence of an oil-soluble polymerization initiator, e.g. benzoyl peroxide, to produce a copolymer of the vinyl chloride containing 2-10wt% alpha-olefin, which is then chlorinated to give normally 60-65wt% chlorine content.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a chlorinated vinyl chloride resin that produces a low-viscosity, transparent solution.0 Vinyl chloride resin is a resin with good chemical resistance. Therefore, vinyl chloride resin is suitable for coating on the surface of objects to prevent corrosion caused by chemicals. The easiest way to apply the resin is to dissolve it in a solvent to form a solution. However, when vinyl chloride resin is dissolved in an organic solvent,
Produces highly viscous solutions, making them unsuitable for application. Therefore, there was a need for a vinyl chloride vdIFF that would produce a low viscosity solution.

Among vinyl chloride # fats, 1 g of copolymerization obtained by copolymerizing vinyl chloride with other suitable m-acids produces a solution with lower viscosity than homopolymerization of vinyl chloride ## decoys. It is known. It is also known that chlorinated vinyl chloride resin obtained by later chlorinating vinyl chloride resin produces a solution with a lower viscosity than vinyl chloride resin. Therefore, when used as a solution, such as in paints or adhesives, chlorinated vinyl chloride resin may be used.

Chlorinated cyclovinyl resin (hereinafter referred to as CPVC) has a lower viscosity than vinyl chloride resin (hereinafter referred to as PvC), but in order to generate a solution with a low viscosity suitable for brush application, it is necessary to use CPVC as a Further improvement was required regarding the composition. Furthermore, when conventional CVPC is dissolved in an organic solvent to form a solution, the solution becomes cloudy and cannot be transparent. Transparency is required for paints, and transparency was also required in the field of adhesives. Therefore, there was a need for a CPVC that would produce clear solutions with low viscosity.

The inventor attempted various experiments in order to meet the above demand. As a result, when vinyl chloride is copolymerized with an α-olefin such as ethylene or propylene, and the copolymer resin thus obtained is chlorinated to produce CPVC,
It was confirmed that this CPVC produces a low viscosity solution. Furthermore, if only a cellulose derivative is selected as a dispersant from among the CPVC obtained in this way and used as a dispersant in the copolymerization process, when the obtained copolymer resin is later chlorinated to make CPVC, the CPVC becomes transparent. It was confirmed that a suitable solution was produced. This invention was completed based on such confirmation.

This invention involves dispersing vinyl chloride and α-olefin in an aqueous medium in which substantially only a cellulose derivative is present as a dispersant, and combining vinyl chloride and α-olefin in the presence of an oil-soluble polymerization initiator. Polymerization to produce a copolymer of vinyl chloride containing 2 to 10% by weight of α-olefin, followed by chlorination of the copolymer,
The present invention relates to a method for producing a chlorinated cyclized vinyl resin that produces a low viscosity, transparent solution.

In this invention, a vinyl chloride copolymer containing 2 to 10% by weight of α-olefin is produced by a suspension polymerization method in a previous step, and the resulting copolymer is chlorinated in a later step. , consists of a combination of processes. It is already known to produce CPVC by a combination of such steps.

This invention utilizes only cellulose derivatives as dispersants during suspension polymerization to produce a clear solution.
Cellulose derivatives, which are novel in terms of obtaining VC, are known as dispersants. Further, as the dispersant, those belonging to surfactants and protective colloids can generally be used, so there are many types. That is, in addition to cellulose derivatives, there are many others such as polyvinyl alcohol, polyvinylpyrrolidone, sodium silicate, and sodium phenate. These dispersants are actually used as a mixture of several types. However, in this invention, a cellulose derivative is selected from among these many dispersants, and this cellulose derivative is used alone.As a result, the resulting PvC is further chlorinated to form CPVC, and a transparent solution is produced. It is particularly different in that it has obtained a cpvc.

In addition, this invention specifically selects a vinyl chloride copolymer resin containing 2 to 10 weight percent of α-olefin as the composition of CPVC, and chlorinates this to produce a low viscosity solution. It is particularly different in that it obtains such CPVC.

Therefore, the CPVC obtained in this invention is easy to handle as a solution by dissolving it in a solvent, and is suitable for applying to other materials as a paint or adhesive.

The dispersant that can be used in this invention is a cellulose derivative. Cellulose derivatives that can be used include:
For example, methylcellulose, ethylcellulose,
Hydroxypropylcellulose, hydroxypropylmethylcellulose, carboxymethylcellulose, etc. Two or more of these cellulose derivatives can be used in combination if necessary, but they cannot be used in combination with a dispersant other than cellulose derivatives, such as polyvinyl alcohol.

The cellulose derivative has a ratio of 0.01 to the monomer to be polymerized.
It is used after being dissolved in water in a proportion of 0.2 parts by weight to 0.2 parts by weight. The mixing ratio and dissolution operation in this case are the same as those that have been performed up to now.

Something other than a dispersant can be present in the aqueous medium obtained in the presence of a cellulose derivative.

In this invention, the aqueous medium described above is placed in a polymerization vessel. In order to prevent gases such as oxygen from remaining in the polymerization container that interfere with polymerization, the gas inside the polymerization container is removed by reducing the pressure. Thereafter, the concentrated vinyl and σ-olefin are forced into an aqueous medium, and the vinyl chloride and α-olefin are dispersed in the aqueous medium and copolymerized in the presence of a polymerization initiator.

α-olefins are, for example, ethylene, propylene, butylene, and the like. These may be used alone or in combination of two or more.

Either vinyl chloride or α-olefin may be placed in the polymerization container first and then the other. The ratio of vinyl chloride to α-olefin is such that α-olefin is added in excess of the ratio of the desired copolymer.

The ratio of the cyclized vinyl and the σ-olefin to the aqueous medium is such that the former accounts for 3 to 5 parts by weight of the latter.

In this invention, an oil-soluble polymerization initiator is present in the polymerization vessel. As the oil-soluble polymerization initiator, one already known as a catalyst for one-pot polymerization of vinyl chloride or olefin is added according to a known procedure. The oil-soluble polymerization initiator is, for example, an organic peroxide such as benzoyl peroxide, laautetrayl peroxide, 2-ethylhexyl peroxycarbonate, etc., or an azo compound such as azobisisobutyronitrile. The addition ratio of these polymerization initiators is 0.01 parts by weight to 0.01 parts by weight per 100 parts by weight of monomers to be polymerized.
The proportion is 1 part by weight.

In the aqueous medium, substances other than those mentioned above, such as antioxidants and FA'w1 moderators, may be added. Further, a small amount of an acrylic monomer or other vinyl monomer may be added as the eighth component, as long as it does not adversely affect the intended use. The amount thereof is within the range of 1 to 10% by weight based on the total amount of α-olefin and vinyl chloride.

In order to carry out turbid polymerization in an aqueous medium, the aqueous medium is heated. It is preferable that the heating is carried out at a temperature of 50 to 80°C. The resulting copolymer is separated from the aqueous medium and transferred to a chlorination step.

The chlorination step in this invention is no different from conventional methods. That is, chlorination can be performed in a suspended state, in a solution state, or in a solid state. When it is in a suspended state, the above copolymer is dispersed in water and chlorine is passed through it to chlorinate it. At this time, chlorination may be promoted by irradiation with ultraviolet rays.

In addition, at this time, a small amount of ketones such as a7tone and methyl ethyl ketone may be added to the water, and if necessary, hydrochloric acid may also be added to the water. A chlorinated solvent such as trichlorethylene or carbon tetrachloride may be added.

During the jII purification process, the chlorine content of the obtained CPVC was 60 to 65 F! %.

The method of this invention is superior to the conventional method in that the obtained CPVC is easily dissolved in a polyhydric solvent, and the resulting solution has a low viscosity and is transparent. Since the solution viscosity is low and it is transparent, it is an excellent component for paints and adhesives, and is industrially useful. Here, the organic solvent refers to a solvent often used in adhesives and paints, and refers not only to a single organic solvent but also to a mixture of a plurality of organic solvents. For example, methyl isobutyl ketone, methyl ethyl ketone, acetone,
A single solvent such as tetrahydrofuran, dimethylformamide, cyclohexanone, methylene chloride, etc., or a mixed solvent such as methyl ethyl ketone/toluene, methyl isobutyl ketone/toluene, ethyl acetate/toluene, etc.

EXAMPLES Hereinafter, the present invention will be explained in detail with reference to Examples and Comparative Examples, and the superior effects of the present invention will be specifically clarified. In Examples and Comparative Examples, parts simply mean parts by weight.

Example 1 (Production of copolymer) In a stainless steel autoclave, 250 parts of ion-exchanged water, 0.25 parts of cellulose derivative (manufactured by Shin-Etsu Chemical Co., Ltd., trade name Metrose 605) 150) and 0.13 parts of oil-soluble polymerization were started. Agent (Product name: Perbutyl ND, manufactured by NOF Corporation)
After putting in the container and vacuum degassing it,
0 parts of vinyl chloride and 19 parts of ethylene were press-fitted.

Thereafter, polymerization was carried out at 60°C for 8 hours to obtain an ethylene-vinyl chloride copolymer. This copolymer had an ethylene content of 7% by weight and an average degree of polymerization of 690.

(#I hydrogenation process) 400 parts of pure water and 100 parts of ethylene-vinyl chloride copolymer were put into a glass reactor, and after vacuum degassing,
Nitrogen was put into the container to maintain normal pressure, and chlorine was blown into the container at 70° C. while irradiating it with a high-pressure mercury lamp to perform chlorination. When the chlorine content reached 63%, the chlorination reaction was stopped, the residual chlorine was removed, and CPVC was obtained by drying.

(Solubility) When the above CPVC was added at a ratio of 15% by weight to a mixed solvent of 4 parts of methyl ethyl ketone and 1 part of toluene, it was easily dissolved. The viscosity of the solution was measured at 25°C using a B-type viscometer.

As a result, the viscosity was 1400 cp, which was found to be low. Moreover, this solution was colorless and transparent.

Comparative Example 1 (Manufacture of copolymer) Except for using 0.2 parts of partially saponified polyvinyl alcohol (manufactured by Nippon Gosei Kagaku Co., Ltd., trade name Go-Sevenol KH-17) instead of the cellulose derivative as a dispersant. An ethylene-vinyl chloride copolymer having an ethylene content of 7% by weight was obtained in exactly the same manner as in Example 1.

(Chlorination Step) The above copolymer was treated in exactly the same manner as in Example 1 to obtain CPVC with a chlorine content of 63% by weight.

(Solubility) When the viscosity of the above CPVC was measured in exactly the same manner as in Example 1, it was found that the viscosity was 1800 cp, which was low viscosity, but the solution was cloudy, which was the same as in Example 1. It was inferior to what I got.

Comparative Example 2 (Production of copolymer) In a stainless steel autoclave, 200 parts of ion-exchanged water and 0.08 parts of cellulose derivative (manufactured by Shin-Etsu Chemical Co., Ltd.) were placed in a stainless steel autoclave.
Metrose (trade name: 90SH100) and 0.04 part of an oil-soluble polymerization initiator (trade name: Baroyl Shi, manufactured by Nihon Yushi Co., Ltd.) were added, the inside of the container was vacuum degassed, and then 100 parts of vinyl chloride was press-fitted. Thereafter, polymerization was carried out at 68° C. for 7 hours to obtain a vinyl chloride polymer having an average polymerization weight of OO.

(Chlorination Step) The above vinyl chloride polymer was chlorinated in exactly the same manner as in Example 1 to obtain CPVC.

(Solubility) When the thus obtained CPVC was dissolved in the mixed solvent of methyl ethyl ketone and toluene of Example 1, the solution became colorless and transparent, but the solution viscosity was high and it was 87.0 OOc.
It was p.

Example 2 (Manufacture of copolymer) In Example 1, 1% propylene was used instead of ethylene.
Propylene
A propylene-vinyl chloride copolymer of k% was obtained. This copolymer had an average degree of polymerization of 450.

(Chlorination Step) The above copolymer was chlorinated in exactly the same manner as in Example 1 to obtain CPVC with a chlorine content of 68% by weight.

(Solubility) When the above CPVC was dissolved in a mixed solvent of methyl ethyl ketone and toluene in exactly the same manner as in Example 1, it was easily dissolved, and the obtained solution was clear and colorless, and had a viscosity of ?
It was criticized for its low viscosity in OOcp.

Comparative Example 8 (Production of copolymer@) Except for using 0.2 parts of polyvinyl alcohol (trade name Go-Sana-nol KH-17, manufactured by Nippon Gosei Kagaku Co., Ltd.) instead of the cellulose derivative as a dispersant, In exactly the same manner as in Example 2, a propylene-vinyl chloride copolymer containing 4% by weight of propylene was obtained. This copolymer had an average degree of polymerization of 450. - (Chlorination step) The above copolymer was chlorinated in exactly the same manner as in Example 2 to obtain CPVC with a chlorine content of 63% by weight.

(Solubility) When the above CPVC was dissolved in a mixed solvent of methyl ethyl ketone and toluene in exactly the same manner as in Example 2, it was easily dissolved and a solution with a viscosity of 50 cp was produced, although the viscosity was low. However, the solution became cloudy and could not become colorless and transparent.

Comparative Example 4 (Production of copolymer) As a dispersant, 0.15 parts of a cellulose derivative (manufactured by Shin-Etsu Chemical Co., Ltd., trade name Metrose 9QSH-100) was used, and propylene was not used at all.
Furthermore, a vinyl chloride homopolymer was obtained in exactly the same manner as in Example 2, except that the polymerization temperature was 85°C. The average degree of polymerization of this polymer was 480.

(Chlorination Step) The above polymer was chlorinated in exactly the same manner as in Example 2 to obtain CPVC with a chlorine content of 63% by weight.

(Solubility) When the above CPVC was dissolved in a mixed solvent of methyl ethyl ketone and toluene in exactly the same manner as in Example 2, the solubility was good and the resulting solution was colorless and transparent, but the viscosity was low. The viscosity was 5000 cp.

Example 8 (Production of copolymer) In Example 1, 0.25 parts of a cellulose derivative (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: Metrose 90) was used as a dispersant.
SH100), 16 parts of ethylene, and 0.5 parts of ethylene.
Add 0.5 parts of chain transfer agent (mercaptoethanol),
The same procedure as in Example 1 was carried out except that the polymerization temperature was set at 65°C, and ethylene-containing 1% a5% ethylene-
A vinyl chloride copolymer was obtained.

This copolymer had an average degree of polymerization of 470.

(Chlorination step) In exactly the same manner as in Example 1, the above copolymer was chlorinated,
A CPVC with a chlorine content of 63% by weight was obtained.

(Solubility) When the above CPVC was dissolved in a mixed solvent of methylethyl+)ton and toluene in exactly the same manner as in Example 1, it was easily dissolved, and the obtained solution was colorless and transparent, and the viscosity was low. 2
00 cp, and was recognized as having a low viscosity.

Comparative Example 5 (Production of copolymer) In Example 3, no chain transfer agent was used, the amount of cellulose derivative was 0.2 parts, the amount of ethylene injected was 8 parts, and the polymerization temperature was 82°C. An ethylene-vinyl chloride copolymer having an ethylene content of 1% by weight was obtained in exactly the same manner as in Example 3 except that δ This copolymer had an average degree of polymerization of 440.

(Chlorination step) In exactly the same manner as in Example 8, the above copolymer was chlorinated,
A CPVC with a chlorine content of 68% was obtained.

(Solubility) When the above CPVC was dissolved in a mixed solvent of methyl ethyl ketone and toluene in exactly the same manner as in Example 3, it was easily dissolved and the resulting solution was clear and colorless, but the viscosity was high. , 4000 cp.

Comparative Example 6 (Manufacture of copolymer) As a dispersant, 0.16 parts of polyvinyl alcohol (trade name, manufactured by Nippon Gosei Kagaku Co., Ltd.) was used instead of the cellulose derivative.
Except for using Go-Sevenol KH-17),
In exactly the same manner as Comparative Example 5, the ethylene content was 1% by weight.
An ethylene-vinyl chloride copolymer was obtained. This copolymer had an average degree of polymerization of 440.

(Chlorination step) In exactly the same manner as in Example 8, the above copolymer was chlorinated,
A CPVC with a chlorine content of 63% was obtained.

(Solubility) When the above CPVC was dissolved in a mixed solvent of methyl ethyl ketone and toluene in exactly the same manner as in Example 3, it was easily dissolved, but the resulting solution was cloudy and not colorless and transparent. In addition, the viscosity was high at 4000 cp.

Example 4 (Manufacture of copolymer) In Example 1, 0.23 parts of a cellulose derivative (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: Metro-X" 60) was used as a dispersant.
An ethylene-vinyl chloride copolymer was obtained in exactly the same manner as in Example 1, except that 10 parts of ethylene was used and the polymerization temperature was 62°C. This copolymer is
It was a copolymer containing 4 ff#% of ethylene and had an average degree of polymerization of 700.

(Chlorination step) In exactly the same manner as in Example 1, the above copolymer was chlorinated,
A CPVC with a chlorine content of 65% by weight was obtained.

(Solubility) The above CPVC was dissolved in a 4:1 mixed solvent of methyl ethyl ketone and toluene in exactly the same manner as in Example 1, and it was easily dissolved. The resulting solution was colorless and transparent, and had a viscosity of 950 cp, which was considered to be low viscosity.

Example 5 (Production of copolymer) In Example 1, 0.2 parts of a cellulose derivative (manufactured by Shin-Etsu Chemical Co., Ltd., trade name Metrose 9QSI) was used as a dispersant.
An ethylene-vinyl chloride copolymer was obtained in exactly the same manner as in Example 1, except that (100) was used, 5 parts of ethylene was used as the α-olefin, and the polymerization temperature was 64°C.

This copolymer had an ethylene content of 2% by weight and an average degree of polymerization of 590.

(Chlorination step) In exactly the same manner as in Example 1, the above copolymer was chlorinated,
A CPVC with a chlorine content of 64% by weight was obtained.

(Solubility) The above CPVC was dissolved in a 4:1 mixed solvent of methyl ethyl and toluene in exactly the same manner as in the actual mfll, and it was easily dissolved. The obtained solution was clear and colorless, and had a viscosity of 'l 50 Cp, which was recognized as low viscosity.

Claims (1)

[Claims] Dispersing vinyl chloride and α-olefin in an aqueous medium in which substantially only a cellulose derivative is present as a dispersant, copolymerizing vinyl chloride and α-olefin in the presence of an oil-soluble polymerization initiator, Chlorinated vinyl chloride resin that produces a low-viscosity, transparent solution, characterized by making a copolymer of vinyl chloride containing 2 to 10% by weight of α-olefin, and then chlorinating the copolymer. manufacturing method.