JPH02269710A - 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 an alkyl maleate. CONSTITUTION:A vinyl chloride copolymer is produced by copolymerizing 99-1wt.% vinyl chloride monomer (A) with 1-99wt.% alkyl maleate (B) of the formula (wherein R<1> and R<2> are each H or a 10C or higher alkyl, and at least either of them is a 10C or higher alkyl), e.g. mono-n-decyl maleate or distearyl maleate). The obtained copolymer has a good balance between thermal property and mechanical property, is remarkably improved in heat resistance, impact 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 nanatsumer.

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 heat resistance of PvC which has been well known for a long time, there is a method (2) of improving heat resistance by chlorinating PvC. Chlorinated PV produced by the method
The heat distortion temperature of C (C-PVC) varies depending on the degree of chlorination of PVC, but for example, at a degree of chlorination of 70% by weight,
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-
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 (ii) improving heat resistance by copolymerizing with a rigid monomer, British Patent No. 1062872 describes a method of producing PVC with excellent heat resistance by copolymerizing vinyl chloride monomer and N-phenylmaleimide. is disclosed. Also, in Special Publication No. 44-124338,
A method for copolymerizing 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, none of the methods has been able to obtain a satisfactory heat-resistant PVC with a well-balanced thermal and mechanical properties.
The emergence of this is now desired.

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 conventional vinyl chloride resins (PVC), the present inventors discovered that vinyl chloride monomers and maleic acid alkyl esters with a specific structure By copolymerizing PvC, it is possible not only to significantly improve the heat distortion temperature compared to PvC, but also to have excellent thermal and mechanical properties with good impact resistance and moldability. They discovered that it was possible to obtain a resin that could be used in a variety of ways, leading to the completion of 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 are hydrogen or an alkyl group having 10 or more carbon atoms). and at least one of which is an alkyl group having 10 or more carbon atoms. In addition, the present invention includes (^) 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 are hydrogen or an alkyl group having 10 or more carbon atoms) and at least one is an alkyl group having 10 or more carbon atoms.
C) Other copolymerizable vinyl monomers - >0 to 40% by weight (with the exception of components (A), (B) and (C)
) is 100% by weight. This invention relates to a method for producing a vinyl chloride copolymer, which comprises copolymerizing a vinyl chloride copolymer.

The present invention will be explained in more detail below.

The maleic acid alkyl esters (B) used in the present invention are represented by the above general formula, and specific examples include mono-n-decyl maleate, monolauryl maleate, monomyristyl maleate, and monocetyl maleate. monomargaryl maleate, monostearyl maleate, monoeicosyl maleate, monoceryl maleate, monomyricyl maleate, mono(5-ethyl-2-nonyl)
malate, mono(7-ethyl-2-methyl-4-undecyl)malate, mono(3,9-diethyl-6-tridecyl)malate, di-n-decylmalate, dilaurylmalate, simiristylmalate, dicetylmalate,
dimargalyl maleate, distearyl maleate, dilauryl maleate, diseryl maleate, similycyl maleate, di(5-ethyl-2-nonyl) maleate, di(7-ethyl-2-methyl-4-undecyl) maleate, di (3
, 9-diethyl-6-tridecyl) maleate, lauryl (stearyl) maleate, lauryl (cetyl) maleate, lauryl (eicosyl) maleate, and stearyl (eicosyl) maleate.

Further, other vinyl monomers (C) copolymerizable with vinyl chloride monomer (8) and maleic acid alkyl esters (B) include, for example, vinyl acetate, vinylidene chloride,
Vinyl ethers, maleic anhydride, vinyl esters, allyl esters, acrylamide, N-alkylacrylamide, N.

N'-dialkyl acrylamide, acrylonitrile,
Examples include isobutylene, 1,3-butadiene, isoprene, acrylic acid and methacrylic esters, styrene, nuclear alkyl-substituted styrenes, and 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 alkyl esters (B) 1~
The proportion is 99% by weight, preferably 5 to 50% by weight (6)%, and when other vinyl monomers (C) are used, the upper limit of the usage amount of the monomer (C) is 40% by weight. be. 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 was 99%.
If it exceeds % by weight, a copolymer with excellent heat resistance and impact resistance cannot be obtained. Furthermore, other vinyl monomer (C)
If a large amount exceeding 0 multilayers is used, the resulting copolymer will have poor heat resistance and resistance! '! 11 properties or moldability tend 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 using the emulsion polymerization method, 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. , a vinyl chloride monomer (^), a maleic acid alkyl ester (B) and, if necessary, another vinyl monomer (C), and polymerize with stirring. Further, if necessary, both or one of these monomers may be added dropwise during polymerization. In this case, there are no particular restrictions on the emulsifier and polymerization initiator used, but
As the emulsifier, sodium lauryl sulfate, sodium alkylbenzenesulfonate, sodium stearate, etc. are preferably used. The polymerization temperature is usually 30~
Polymerization is carried out at a temperature of 100°C. The polymerization time varies depending on the polymerization initiator and polymerization temperature, but it is usually preferably carried out for 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, add vinyl chloride monomer (A), maleic acid alkyl ester (B), and other vinyl monomer (C) to water if necessary.
) and polymerize using a radical initiator while mechanically stirring and dispersing in the presence of a dispersant. Also, in this case, polymerization can be carried out while dropping the 7-mer as necessary, and the atmosphere inside the reactor can be replaced with an inert gas such as nitrogen, helium, argon, carbon dioxide gas, etc. is preferred. As the polymerization initiator, organic peroxides such as benzoyl peroxide, di-t-butyl peroxide, lau[coil peroxide], and azo compounds such as azobisisobutyronitrile and azobiscyclohexane are preferably used. . Furthermore, methyl cellulose, polyvinyl alcohol, gelatin, polyvinylpyrrolidone, etc. are used as a dispersing agent for suspension stabilization. The polymerization temperature varies depending on the polymerization initiator, but is preferably in the range of 30 to 100°C. Polymerization time varies depending on the type of polymerization initiator and polymerization temperature, but
1 to 24 hours is appropriate. 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 vinyl chloride copolymer obtained by the method of the invention has the following properties:
It has well-balanced thermal properties and mechanical properties, and in particular, has improved heat resistance, impact resistance, and moldability by -8 times compared to conventional vinyl chloride resins.

Therefore, the vinyl chloride copolymer obtained by the present invention can be used in piping materials, valves, automatic width members, window frames, and industrial boards, which have conventionally had problems in heat resistance, impact resistance, and moldability. , blow bottle, vibrator, film sheet, weak II
It is particularly effective as a material for equipment parts, etc.

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

Example 1 1,900 ml of distilled water, 5 g of sodium lauryl sulfate, and 5 g of potassium persulfate were charged into an autoclave with a capacity of 51 equipped with a stirrer, a pressure gauge, and a thermometer. After degassing in a vacuum, the gas phase of the autoclave was purged with nitrogen. Replaced. The contents of the autoclave were heated to 50° C. over 15 minutes.

Next, under stirring, 700 (1) of vinyl chloride was injected under pressure, and then 120 g of dilauryl male (1-1) was added with 3 (3) methanol.
3 at! of the solution obtained by mixing with 00d! The reaction was carried out while continuously adding at a rate of /InO. After the addition is complete, the reaction is
After continuing for 40 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 filtration and drying to obtain copolymer (1) as a white powder.

Example 2 In Example 1, a solution obtained by mixing 100 g of distearyl maleate with 400 df of methanol was used instead of a solution obtained by mixing dilauryl maleate 1209 with 300 df of methanol. The same operation as in Example 1 was carried out to obtain a white powder copolymer (2).

Example 3 2000 d of distilled water in which 2 g of polyvinyl alcohol was dissolved and 2 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 ml in a dry ice-methanol bath.
While cooling to ℃, the atmosphere of the autoclave was replaced with nitrogen.

Next, vinyl chloride monomer 700 (1, a solution obtained by mixing 100 g of distearyl malate in 200 m of methanol and vinyl acetate monomer 509 were charged, and the contents of the autoclave were heated to 60 ° C. in 15 minutes. The reaction was carried out by maintaining the same temperature and stirring at 300 r, l) and 111 for 12 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 A white powder comparative copolymer (1) was obtained by carrying out exactly the same operation as in Example 2 except that N-cyclohexylmaleimide 100Q was charged together with the vinyl chloride monomer instead of 100 g of distearyl maleate. I got it.

Example 4 Co-Φ coalescence (1) obtained in Examples 1 to 3 and Comparative Example 1
-(3) and comparative copolymer (1), 3.0 parts by weight of dibutyltin malate stabilizer and 0.31 parts by weight of butyl stearate as a lubricant were added, and the surface temperature was 190°C. The mixture was kneaded for 4 minutes using two rolls. 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: Jrs K 67402) 1
1 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 formula, chemical formula, table, etc. ▼ (In the formula, R^1 and R^2 are the same or different groups and represent hydrogen or an alkyl group having 10 or more carbon atoms, and at least one has a carbon number A method for producing a vinyl chloride copolymer, which comprises copolymerizing 1 to 99% by weight of a maleic acid alkyl ester represented by 10 or more alkyl groups. 2. (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 alkyl esters represented by
% by weight or less (however, components (A), (B) and (C)
) is 100% by weight. ) A method for producing a vinyl chloride copolymer, comprising copolymerizing.