JPH02269713A - Production of vinyl chloride copolymer - Google Patents

Abstract

PURPOSE:To produce a vinyl chloride copolymer excellent in heat resistance, impact resistance and moldability by copolymerizing a vinyl chloride monomer with a phenylmethyl maleate. CONSTITUTION:A vinyl chloride copolymer is produced by copolymerizing 99-1wt.% vinyl chloride monomer (A) with 1-99wt.% phenylmethyl maleate (B) of the formula [wherein R<1> and R<2> are each H or a (nucleus-substituted) phenylmethyl, and at least either of them is a (nucleus-substituted) phenylmethyl], e.g. monophenylmethyl maleate or di(phenylmethyl) maleate. The obtained copolymer has a good balance between thermal property and mechanical property, is remarkably improved in heat resistance and moldability as compared with a conventional vinyl chloride resin, and is useful as the materials for piping materials, valves, automobile members, pipes, films, sheets, weak-current machine members, etc., which have been problematic in heat resistance, impact resistance and moldability.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for producing a vinyl chloride copolymer having excellent heat resistance, impact resistance and moldability.

<Object of the Invention> Vinyl chloride resin (PVC) is an inexpensive resin that is excellent in mechanical properties such as rigidity and tensile strength, as well as chemical resistance, oil resistance, and flame retardance.

However, it has a fatal drawback of poor thermal stability and low heat resistance, so its use is currently limited.

Therefore, various attempts have been made to improve the heat resistance of PvC, including: (1) blending it with a highly heat resistant polymer;

■Method of chlorinating.

■Method of copolymerizing with rigid monomers.

and so on.

■ In the method of blending with a highly heat-resistant polymer, P
Due to the low thermal stability of vC, it is not possible to raise the processing temperature extremely, and it is difficult to mix the polymer with PVC. In addition, good compatibility between the polymer and PVC is required. It is not easy to develop a resin that can satisfy these conditions, and at present no resin with a high heat distortion temperature has been developed by this method.

Further, as a method for improving the heat resistance of PvC which has been well known for a long time, there is a method (2) of improving the heat resistance by chlorinating PVC. Chlorinated PV produced by the method
The heat deformation temperature of C (C-PVC) varies depending on the degree of chlorination of PvC, but for example, when the degree of chlorination is 70,
Heat-resistant PVC with a glass transition temperature of 95° C. and high heat resistance has been obtained.

However, the disadvantage of c-pvc is that it has significantly poor moldability compared to PVC and is subject to severe thermal decomposition during molding. In particular, c- with a chlorine content exceeding 64%
In the case of PVC, severe thermal decomposition occurs during melt processing during molding. Therefore, in order to prevent this, the molding temperature cannot be raised, causing significant difficulty in molding the resin.

Regarding the method of improving heat resistance by copolymerizing with a rigid 7-mer, British Patent No. 1062872 describes a method for producing PvC with excellent heat resistance by copolymerizing polychloride monomer and N-phenylmaleimide. A method is disclosed. Also, in Special Publication No. 44-12433,
A method for co-merging vinyl chloride monomer and N-cyclohexylmaleimide is disclosed. however,
In any of these methods, although the heat resistance is improved by copolymerization with an imide compound, the impact resistance is reduced, so there is a problem that the uses of the resin are extremely limited.

In this way, both methods provide a satisfactory heat resistance p v c with a well-balanced thermal and mechanical properties.
h<n, and the emergence of heat-resistant PvC with such well-balanced physical properties has become desirable.

Thus, an object of the present invention is to provide a method for producing a vinyl chloride copolymer having excellent heat resistance, impact resistance, and moldability.

<Means and effects for solving the problems> As a result of intensive studies to improve the drawbacks of these conventional vinyl chloride resins (PVC), the present inventors discovered that vinyl chloride monomer and maleic acid phenylmethyl ester with a specific structure By copolymerizing PvC, it is possible not only to improve the heat distortion temperature to a greater degree than PvC, but also to create thermal and mechanical properties that have both good impact resistance and moldability. They discovered that a resin with excellent properties could be obtained and completed the present invention.

That is, the present invention comprises (A) 99 to 1% by weight of a vinyl chloride monomer, and (B) the following general formula (wherein R1 and R2 are the same or different groups and may be hydrogen or nuclear substituted. A vinyl chloride characterized by copolymerizing 1 to 99% by weight of a maleic acid phenylmethyl ester represented by a phenylmethyl group, at least one of which is a phenylmethyl group that may be nuclear-substituted. Regarding the method for producing the copolymer,
The present invention includes (A) 99 to 1% by weight of vinyl chloride monomer,
(B) The following general formula (wherein R1 and R2 are the same or different groups and represent hydrogen or a phenylmethyl group which may be substituted with a nucleus, and at least one is a phenylmethyl group which may be substituted with a nucleus. 1 to 99% by weight of a maleic acid phenylmethyl ester represented by The present invention relates to a method for producing a vinyl chloride copolymer, characterized in that the total amount of (C) and (C) is 100 Zr)

The present invention will be explained in more detail below.

The maleic acid phenylmethyl esters (B) used in the present invention are those represented by the above general formula,
Specific examples include monophenyl methyl malate,
Mono(2-chlorophenylmethyl)malate, mono(4
-chlorophenylmethyl)malate, mono(2-methylphenylmethyl)malate, mono(4-methylphenylmethyl)malate, mono(2-methoxyphenylmethyl)malate, mono(4-methoxyphenylmethyl)malate, mono(2- fluorophenylmethyl) malate,
Mono(2,4,6-difluorophenylmethyl)malate, mono(3-nitrophenylmethyl)malate, di(phenylmethyl)malate, di(2-chlorophenylmethyl)malate, di(4-chlorophenylmethyl)malate , di(2methylphenylmethyl)malate, di(
4-methylphenylmethyl)malate, di(2-methoxyphenylmethyl)malate, di(4-methoxyphenylmethyl)malate, di(2-fluorophenylmethyl)malate, di(2,4,6-dolifluorophenyl) methyl)malate, di(3-nitrophenylmethyl)malate, phenylmethyl(2chlorophenylmethyl)malate, phenylmethyl(4-chlorophenylmethyl)malate, phenylmethyl(2-methylphenylmethyl)
Malate, phenylmethyl (4-methylphenylmethyl) malate, phenylmethyl (2-methoxyphenylmethyl) malate, phenylmethyl (4-methoxyphenylmethyl) malate, phenylmethyl (2-fluorophenylmethyl) malate, phenylmethyl (2-methoxyphenylmethyl) malate, ,4,6
-dryfluorophenylmethyl)malate, and the like.

Furthermore, other vinyl monomers (C) copolymerizable with vinyl chloride monomer (A) and maleic acid phenylmethyl esters (B) include, for example, vinyl acetate, vinylidene chloride, vinyl ethers, maleic anhydride, and vinyl esters. , allyl esters, acrylamide, N-alkylacrylamide, N,N'-dialkyl acrylamide, acrylonitrile, isobutylene, 1,3-butadiene, isoprene, acrylic and methacrylic esters, styrene, nuclear alkyl-substituted styrenes, Examples include nuclear halogen-substituted styrenes.

The amount of each monomer used in the present invention is 99 to 1% by weight of vinyl chloride monomer (A), preferably 95 to 1% by weight.
50% by weight, maleic acid phenylmethyl esters (B
) 1 to 99% by weight, preferably 5 to 50% by weight, and when other vinyl monomers (C) are used, the upper limit of the usage amount of the monomer (C) is 40% by weight. If the amount of vinyl chloride monomer (A) used is less than 1% by weight, the inherent moldability and economic efficiency of the vinyl chloride resin will be impaired.

In addition, the amount of vinyl chloride monomer (A) used is 99% by weight.
If it exceeds this amount, a copolymer with excellent heat resistance and impact resistance cannot be obtained. Furthermore, another vinyl monomer (C)
If the amount exceeds %, the heat resistance, impact resistance, or moldability of the resulting copolymer tends to decrease.

In the present invention, as the copolymerization method used, any method such as bulk polymerization, solution polymerization, suspension polymerization, or emulsion polymerization can be adopted.

When producing a copolymer by emulsion polymerization, water, an emulsifier, and a polymerization initiator are charged into a reactor, and the atmosphere inside the reactor is replaced with an inert gas such as nitrogen, helium, argon, or carbon dioxide. Vinyl chloride monomer (A), maleic acid phenylmethyl esters CB) and, if necessary, other vinyl monomers (C) are added and polymerized with stirring. Further, if necessary, both or one of these seven polymers may be polymerized while being dropped. In this case, there are no particular restrictions on the emulsifier and polymerization initiator used, but sodium lauryl sulfate, sodium alkylbenzenesulfonate, sodium stearate, and the like are preferably used as the emulsifier.

The polymerization temperature is usually in the range of 30 to 100°C. The polymerization time varies depending on the polymerization initiator and polymerization temperature, but it is usually preferably 1 to 24 hours. Post-treatment of the product obtained by emulsion polymerization is carried out by known methods such as salting out, filtration, and drying.

When producing a copolymer by a suspension polymerization method, vinyl chloride monomer (A), maleic acid phenylmethyl esters (B), and if necessary other vinyl monomers (C) are added to water, and a dispersing agent is added. Polymerization may be carried out using a radical initiator while mechanically stirring and dispersing in the presence of the polymer. Also,
Even in this case, polymerization can be carried out while dropping the monomer as needed, and it is preferable to replace the atmosphere in the reactor with an inert gas such as nitrogen, helium, argon, carbon dioxide, or the like. As the polymerization initiator, organic peroxides such as benzoyl peroxide, di-t-butyl peroxide, and lauroyl peroxide, and azo compounds such as azobisisobutyronitrile and azobiscyclohexane are preferably used. Furthermore, as a dispersant for stabilizing the suspension, methylcellulose, polyvinyl alcohol, gelatin, polyvinylpyrrolidone, etc. are used. The polymerization temperature varies depending on the polymerization initiator, but is preferably in the range of 30 to 100°C.

The polymerization time varies depending on the type of polymerization initiator and the polymerization temperature, but is suitably 1 to 24 hours. Post-treatment of the polymer obtained by the suspension polymerization method is carried out by known methods such as oven separation and drying.

<Effects of the Invention> The petrified vinyl copolymer obtained by the method of the present invention has the following properties:
It has well-balanced thermal and mechanical properties, and in particular, it has significantly improved heat resistance, impact resistance, and moldability compared to conventional vinyl chloride resins.

Therefore, the vinyl chloride copolymer obtained by the present invention can be used in piping materials, valves, automobile parts, window frames, industrial boards, etc., which have conventionally had problems in heat resistance, impact resistance, and moldability. It is particularly effective as a material for blow bottles, pipes, film sheets, parts for light electrical equipment, etc.

<Examples> The present invention will be specifically described below with reference to Examples and Comparative Examples.

Example 1 1900 d of distilled water, 59 sodium lauryl sulfate, and 3 g of potassium peroxide were charged into an autoclave with a capacity of 51 equipped with a stirrer, a pressure gauge, and a thermometer. After degassing in vacuum, the gas phase of the autoclave was The atmosphere was replaced with nitrogen. The contents of the autoclave were heated to 50° C. over 15 minutes.

Next, vinyl chloride monomer 7009 was injected under stirring, and then a solution obtained by mixing 120 g of di(phenylmethyl)malate in 300 d of methanol was reacted while continuously adding at a rate of 3 d/win. After the addition is complete, the reaction is
After continuing for 50 minutes, the reaction solution was cooled to 40°C to obtain a copolymer latex.

A 15% aqueous calcium chloride solution was added to the obtained latex to solidify it, followed by filtering and drying to obtain copolymer (1) as a white powder.

Example 2 In Example 1, di(phenylmethyl)malate 12
0g of methanol 300#Ii! Di(2-methylphenylmethyl)malate 10 instead of the solution obtained by mixing
A white powder copolymer (2) was obtained by carrying out the same operation as in Example 1, except that a solution obtained by mixing 0 (J) with 400 d of methanol was used.

Example 3 2000 Id of distilled water in which 2 g of polyvinyl alcohol was dissolved and 1 g of lauroyl peroxide were added to a 51 volume autoclave equipped with a stirrer, a pressure gauge, and a thermometer, and the autoclave was heated to -20 methanol in a dry ice methanol bath.
While cooling to ℃, the atmosphere of the autoclave was replaced with nitrogen.

Next, 7000 grams of vinyl chloride and 100 grams of di(2-methylphenylmethyl)malate were added to 200 grams of methanol.
The solution obtained by mixing 1 dl and vinyl acetate monomer 5
0! + and heat the contents of the autoclave to 15
After raising the temperature to 60℃ in minutes, keep it at the same temperature and heat it for 300r.
The reaction was carried out by stirring at p, a+ for 8 hours.

After the polymerization reaction is complete, return the temperature of the autoclave to room temperature,
The residual vinyl chloride monomer was removed from the autoclave using Persil, and the autoclave was then purged with nitrogen. The produced copolymer was washed with water, filtered, and dried to obtain a white powder copolymer (3).

Comparative Example 1 Exactly the same operation as in Example 2 was carried out except that N-cyclohexylmaleimide 100Q was charged in place of di(2-methylphenylmethyl)malate 100 (It) together with the vinyl chloride monomer, and a white powder was prepared. Comparative copolymer (
1) was obtained.

Example 4 Copolymer (1) obtained in Examples 1 to 3 and Comparative Example 1
-(3) and comparative copolymer (1), 3.0 parts by weight of a dibutyltin malate stabilizer and 0.3 parts by weight of butyl stearate as a lubricant were blended, and the surface temperature was 190°C. The mixture was kneaded using the main roll for 4 minutes. The obtained rolled sheet was press-molded at 190° C. for 5 minutes, and the sheet obtained was used as a test piece, and its physical properties were measured by the method shown below. The results are shown in Table 1.

Comparative Examples 2 and 3 in Table 1 are for comparison between commercially available chlorinated PVC (C-PVC) and general-purpose PVC with an average degree of polymerization of 1000.

The method used for the evaluation is as follows.

1) Softening temperature: JIS K 67402)
Impact value: JIS K 71113) Molding processability: Evaluated by flow rate measured with a Koka type flow tester.

Claims (1)

[Claims] 1. (A) 99 to 1% by weight of vinyl chloride monomer, and (B
) The following general formula ▲ Numerical formulas, chemical formulas, tables, etc. is a phenylmethyl group which may be substituted with a nucleus.) 1 to 99% by weight of maleic acid phenylmethyl esters are copolymerized. 2. (B) The vinyl chloride system according to claim 1, wherein R^1 and R^2 in the general formula representing maleic acid phenylmethyl esters are phenylmethyl groups which may be substituted with nuclear alkyl or nuclear halogen. Method for producing copolymer. 3. (A) 99-1% by weight of vinyl chloride monomer, (B)
The following general formula ▲ includes mathematical formulas, chemical formulas, tables, etc. 1 to 99% by weight of maleic acid phenylmethyl esters (optionally substituted phenylmethyl group) and (C) more than 0 to 40% by weight of other copolymerizable vinyl monomers
% by weight or less (with the exception that components (A), (B) and (C)
) is 100% by weight. ) A method for producing a vinyl chloride copolymer, which comprises copolymerizing a vinyl chloride copolymer. 4. (B) The vinyl chloride system according to claim 3, wherein R^1 and R^2 in the general formula representing maleic acid phenylmethyl esters are phenylmethyl groups which may be substituted with nuclear alkyl or nuclear halogen. Method for producing copolymer.