JPS61207417A - Production of vinyl chloride copolymer emulsion - Google Patents

Abstract

PURPOSE:The titled emulsion excellent in viscosity stability and storage stability and stable in quality, by polymerizing part of vinyl chloride in the initial stage of polymerization and emulsion-copolymerizing the balance of the vinyl chloride with an acrylate. CONSTITUTION:3-30wt%, based on the total feed, vinyl chloride is added to a solution in which an emulsifier such as an alkyl-(aryl)sulfonate, a polymerization initiator such as potassium persulfate, etc., are dissolved. After initiating the polymerization of the obtained mixture, an acrylate such as methyl (meth) acrylate and, optionally, at most 10wt% monomer such as acrylonitrile are added to the reaction system continuously or in portions to effect emulsion copolymerization.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing a vinyl chloride resin emulsion having excellent viscosity stability and storage stability of a plasticized emulsion.

[Conventional technology]

Conventional vinyl chloride-based four fat emulsion YK111! Known methods for producing such materials include the two-batch charging method, the Motsumer addition method, the emulsion addition method, and the 31H1 polymerization method.

For this purpose, it is effective to add vinyl chloride and a monomer copolymerizable with it continuously or in batches.

The vinyl chloride resin emulsion polymerized in this way is used in adhesives, paints, various binders, cement admixtures, etc., but when lowering the minimum film forming temperature, plasticizers are added to reduce the temperature from room temperature to 15"C. Plasticized to a certain extent.

However, if the plasticized product obtained here is stored for a long period of time, the viscosity increases and the plasticizer tends to separate. Savings R
@When the temperature reaches 50゛C or higher, their current R is promoted,
When the process is too difficult, the plasticized material turns into rubber.

References Emulsion latex hendopook Taiseisha P-277-288 Tanbi to Polymer 13 (4) 10-25 [@Problems to be decided by Ming 5] Viscosity stability of vinyl chloride resin emulsion plastics Stable storage! Improve P.

[Means for solving problems]

This BA is made by adding vinyl chloride and acrylic ester to a hard salt via milk powder, and then using a vinyl rod, number λ ~ 60% by weight.
This is a method for producing a vinyl chloride copolymer emulsion, which is characterized in that polymerization is started by adding 7M of monomer at the initial stage of polymerization, and then 7M of monomer is added continuously or in portions.

In the present invention, the amount of vinyl chloride cap added at the initial stage of polymerization is 3 to 30%
(weight ink % tare'), particularly preferably 5 to 15 weight t%^. If it is less than 6% by weight, the viscosity stability and storage stability of the plasticized emulsion will not be improved, and if it exceeds 60% by weight, the polymer composition in the emulsion particles cannot be made uniform.

In the emulsion polymerization method of the present invention, the monomer addition method is as follows:
Any method may be used, including adding the monomer component alone or as a mixture of each monomer, adding the monomer after mixing with an emulsion, or adding continuously or in parts, without any particular limitation. Alternatively, seeding polymerization using a monomer addition method may be used.

For example, methyl acrylate, ethyl acrylate, ethyl acrylate or acrylic acid 2-
These include acrylic esters such as ethylhexyl, methacrylic esters such as methyl methacrylate, ethyl methacrylate, and butyl methacrylate.

In the present invention, in addition to vinyl chloride and acrylic acid esters, monomers copolymerizable with these, such as styrene, acrylonitrile, vinylidene chloride, unsaturated acids and salts thereof such as acrylic acid and methacrylic acid, and itaconic acid are used. , unconjugated dibasic acids such as maleic acid and their salts,
and half-esters, hydroxyl-containing vinyl compounds such as 12-hydroxyethylacrylamide or N-methylol acrylamide, allyl compounds such as triallyl cyanurate, trimethylolpropane sialyl ether or sialyl phthalate, and epoxy-containing compounds such as glycysol methacrylate. Unsaturated compound, methacrylic acid-2-(1-
An aziridine compound such as (azilysyl)ethyl can be used within a range of 10 or less.

The emulsifier and protective colloid used in this polymerization may be conventionally known ones, such as various alkyl gold W4 salts, alkylaryl sulfone fIN groups, alkyl sulfonic acid groups, polyoxyethylene alkylaryl ethers, and polyoxyethylene sorbitan derivatives. anionic and nonionic surfactants such as, reactive interfacial agents such as vinyl sulfonate, water-soluble stabilizing colloids such as polyvinyl alcohol, alkyl cellulose, hydroxyalkyl cellulose, and polyacrylate. .

Further, the polymerization initiator may be a conventionally known one, such as a water-soluble polymerization initiator such as potassium persulfate and amthonium persulfate, penzoylpero! ? An oil-based initiator such as SIDE, or a dox-based polymerization initiator made of a peroxide of these and a reducing agent, etc., are used.

In addition, chain transfer agents, inorganic metal salts, heptammonicum salts, and other known agents may also be used.

Examples 1 to 8 (Polymerization) A polymerization can (50 mm with a stirrer) was charged with the initial additives listed in Table 1, such as an emulsifier, ash emulsion sodium pyrophosphate, potassium ammonium persulfate solution, and pure water, and then heated under vacuum. After degassing, nitrogen was filled in, and vacuum degassing was repeated 5 times to sufficiently deoxidize, and then the temperature was raised to 50°C. Therefore, vinyl chloride was added to 155
After adding 011, vinyl chloride, the second monomer, and the sixth monomer/emulsion listed in Table 1 were added continuously (however, vinyl chloride was added in portions for 750 minutes at a time).

The continuous addition 7FD was carried out for 60 hours, and the polymerization was continued for an additional 5 hours to complete the polymerization. The polymerization temperature was kept constant at 50°C.
It was placed in an autoclave (made of stainless steel) and plasticized under the following conditions.

Plasticized chronic emulsion 700 II pure water 1
60I Dioctyl phthalate 140I Neopellex A66 151128% ammonia water 6.5Ii Plasticity 120"0 Plasticization time 2 hours The emulsion a obtained here is shown in Table 6.

Comparative Examples 1 to 8 Polymerization and plasticization were performed in the same manner as Examples 1 to 8 (
Table 2). Table 4 shows the emulsion a obtained here.

〔Effect of the invention〕

The viscosity stability and storage stability of the vinyl chloride-based mqa emulsion plastic product were improved, and it became possible to withstand long-term storage at high temperatures, resulting in a vinyl chloride-based resin emulsion with stable quality.

Patent applicant: Denki Kagaku Kogyo Co., Ltd. Procedural amendment June 13, 1985 Manabu Shiga, Commissioner of the Patent Office1, Indication of the case Patent Application No. 48157, filed in 19852, Name of the invention: Vinyl chloride copolymer Emulsion manufacturing method 3, relationship with the amended case Patent applicant address 1-4-1 Yurakucho, Chiyoda-ku, Tokyo 0100
Column 5 of the detailed description of the invention in the specification, content of amendment ■) Post-added vinyl chloride r4 in Example No. 1 in Table 1 on page 8
Correct 64J to r420J.

Claims (1)

[Claims] When emulsion copolymerizing vinyl chloride and acrylic ester,
Production of a vinyl chloride copolymer emulsion, characterized in that polymerization is started by adding 3 to 30% of the total amount of vinyl chloride charged at the initial stage of polymerization, and then the entire amount of monomer is added continuously or in portions. Law.