JPH0680137B2 - Chlorinated vinyl chloride resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a chlorinated vinyl chloride resin composition having good heat resistance, excellent processability, and high impact resistance.

(Prior Art) Vinyl chloride resin is widely used for pipes, plates, films, sheets, etc. because it has high rigidity and tensile strength and excellent weather resistance, flame resistance, and chemical resistance. However, vinyl chloride resin has a low softening point and lacks heat resistance. For example, 7
Since it softens at 0 to 80 ℃ and causes thermal deformation, it cannot be used at higher temperatures. In order to impart heat resistance to vinyl chloride resin, attempts have been made to further chlorinate it after the resin is manufactured. The heat resistance of such a chlorinated vinyl chloride resin improves as the degree of chlorination increases. However, a chlorinated vinyl chloride resin with a high degree of chlorination has poor flowability, resulting in poor processability. In order to improve the processability, it is possible to add a lubricant such as stearic acid or its ester to this chlorinated vinyl chloride resin. These are used for polyvinyl chloride to improve moldability. However, in order to obtain the desired processability, it is necessary to add a large amount of lubricant, which lowers the softening point of the obtained resin composition. Moreover, the lubricant leached out so much that it could not be used as a molded product.

In order to solve these drawbacks, attempts have been made to blend a modified resin with a chlorinated vinyl chloride resin. Examples of the modified resin include chlorinated polyethylene (Japanese Patent Publication No. Sho 38-12175).
No.), polypropylene, or a combination of polypropylene and polyethylene (JP-B-42-8224), ABS, or ABS and MBS
Combination (JP-B-43-5219), ethylene-vinyl acetate copolymer (JP-B-43-12010), ethylene-ethyl acrylate copolymer (JP-B-43-18464), acrylonitrile (JP-B-45- 1624), and polyolefin rubber or epichlorohydrin rubber (Japanese Patent Publication No. 47-45420). However, such a modified resin cannot obtain desired processability with a small amount of compounding, and if it is compounded with a large amount, the softening point of the obtained composition decreases and the heat resistance deteriorates.

(Problems to be Solved by the Invention) The present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide good heat resistance, excellent workability, and impact resistance. It is to provide a highly chlorinated vinyl chloride resin composition.

(Means for Solving Problems) In the present invention, a chlorinated polyvinyl chloride excellent in heat resistance and impact resistance is blended with a vinyl chloride copolymer having an N-substituted maleic acid imide unit. The work has been completed based on the inventor's knowledge that the workability can be improved while maintaining the heat resistance.

The chlorinated vinyl chloride resin composition of the present invention comprises (1) 70 to 95 parts by weight of chlorinated polyvinyl chloride obtained by post-chlorinating polyvinyl chloride having an average degree of polymerization of 400 to 2000, and (2) vinyl chloride unit. It contains 5 to 30 parts by weight of a vinyl chloride copolymer having an average degree of polymerization of 500 to 1500 and having 70 to 95% by weight and an N-substituted maleimide unit of 5 to 30% by weight, thereby achieving the above object. To be done.

The average degree of polymerization of polyvinyl chloride is 400 to 2000, preferably 60.
It is set to 0-1400. When the average degree of polymerization of polyvinyl chloride falls below 400, the impact resistance of chlorinated polyvinyl chloride decreases. When the average degree of polymerization exceeds 2000, the melt viscosity of chlorinated polyvinyl chloride becomes high and the moldability deteriorates. The chlorine content of chlorinated polyvinyl chloride is preferably 60 to 70% by weight. Below 60% by weight, the heat resistance of chlorinated polyvinyl chloride decreases. If it exceeds 70% by weight, the melt viscosity of chlorinated polyvinyl chloride becomes high and the workability deteriorates.

The N-substituted maleimide unit serving as a constitutional unit of the vinyl chloride copolymer is in the range of 5 to 30% by weight, preferably 10 to 25% by weight. If it is less than 5% by weight, the physical properties of the vinyl chloride-based copolymer will be close to those of polyvinyl chloride, and the heat resistance of the copolymer will decrease. If it exceeds 30% by weight, not only the impact resistance of the vinyl chloride-based copolymer decreases but also the melt viscosity increases, so that the moldability also deteriorates. There is no transparency. The N-substituted maleic imide is represented, for example, by the following formula: Here, R ¹ and R ₂ are the same or different and each is hydrogen, chlorine, bromine, fluorine, a cyano group or an alkyl group having 1 to ³ carbon atoms, and R ³ is an unsubstituted or substituted group having 1 to 30 carbon atoms. It is an aliphatic group, a cycloaliphatic group or an aromatic group. R
³ is preferably a t-butyl group, an isopropyl group, a cyclohexyl group, a phenyl group, or an o-chlorophenyl group.

The chlorinated vinyl chloride resin composition of the present invention comprises 70 to 95 parts by weight of chlorinated polyvinyl chloride, preferably 75 to 90 parts by weight, and 5 to 30 parts by weight of a vinyl chloride copolymer, preferably 10 to
Contains 25 parts by weight. If the vinyl chloride-based copolymer falls below this range, the desired processability of the chlorinated vinyl chloride resin composition cannot be obtained, and above this range, the heat resistance and resistance of the chlorinated vinyl chloride resin composition are reduced. Impact resistance decreases.

In this chlorinated vinyl chloride resin composition, in the above composition range, when the chlorine content of chlorinated polyvinyl chloride is low, the N-substituted maleic acid imide unit of the vinyl chloride copolymer is increased and the chlorinated polyvinyl chloride resin is chlorinated. The higher the chlorine content of polyvinyl chloride, the less N-substituted maleimide units. This maintains the balance between heat resistance, impact resistance and moldability of the chlorinated vinyl chloride resin composition.

The vinyl chloride-based copolymer of the present invention is optionally copolymerized with a monomer copolymerizable with vinyl chloride within a range that does not impair the characteristics of the obtained chlorinated vinyl chloride resin composition. May be. Any known polymerization method can be applied to the method for synthesizing the vinyl chloride copolymer, and examples thereof include emulsion polymerization method, suspension polymerization method, solution polymerization method, and precipitation polymerization method.

Here, as a method for producing the post-chlorinated polyvinyl chloride used, for example, polyvinyl chloride is suspended in an aqueous solvent containing a solvent such as chloroform, or in an aqueous medium containing no solvent, and There is a method of chlorinating with a photocatalyst, or a method of chlorinating with a photocatalyst or a peroxide catalyst by a gas phase flow method. In the present invention, post-chlorinated polyvinyl chloride means not only a chlorinated product of a vinyl chloride homopolymer but also a vinyl chloride-ethylene copolymer, a vinyl chloride-
It also includes a composition obtained by chlorinating a vinyl chloride copolymer, a chlorinated product of a vinyl chloride copolymer such as a vinyl chloride-vinylidene chloride copolymer, or a mixture thereof.

The chlorinated vinyl chloride resin composition of the present invention contains known additives such as impact modifiers, stabilizers, lubricants, processing aids, which are conventionally blended with chlorinated polyvinyl chloride or vinyl chloride resin.
Fillers, UV absorbers, pigments may be used. Molding of this composition is carried out by a usual molding method such as extrusion molding, injection molding or calender molding.

(Examples) The present invention will be described below with reference to Examples.

Example 1 (1) Preparation of chlorinated polyvinyl chloride Polyvinyl chloride having an average degree of polymerization of 1000 and obtained by suspension polymerization 30
0 g and 1500 g of demineralized water were put into a glass reactor equipped with a stirrer, and the inside of the reactor was replaced with N ₂ gas. Next, add 70% chlorine gas in the container.
The chlorination reaction was carried out for 5 hours by flowing it at a rate of 1 / Hr and irradiating it with a 100 W mercury lamp at 70 ° C. After the reaction was completed, the inside of the vessel was replaced with N ₂ gas to obtain chlorinated polyvinyl chloride. The chlorine content of this chlorinated polyvinyl chloride was 65%. The chlorine content was measured by the oxygen flask combustion method.

(2) Synthesis of vinyl chloride-based copolymer 14 liters of demineralized water containing 0.3% partially saponified polyvinyl alcohol as a dispersant for suspension polymerization, N-cyclohexyl maleic imide was added to a stainless steel autoclave with a stirrer with an internal volume of 25 liters. 0.92 kg, and 10 g of t-butyl peroxy neodecanoate as a polymerization initiator were charged. After evacuation under reduced pressure, 4.0 kg of vinyl chloride monomer was injected under pressure. While rotating the stirrer of the autoclave at 660 rpm, keep the temperature at 50 ° C.
And was polymerized for 8 hours. After completion of the polymerization reaction, unreacted vinyl chloride monomer was removed and then filtered. Filtered material
After vacuum drying at 50 ° C for 24 hours, 3.8 kg of a white powdery granular copolymer was obtained. The copolymer contained 80% by weight of vinyl chloride units and 20% by weight of N-cyclohexylmaleimide units. The average degree of polymerization of the copolymer was 700. The maleimide unit was measured by the oxygen flask combustion method. The average degree of polymerization is JIS K-67.
It measured according to 21 (vinyl chloride resin test method).

(3) Preparation of Chlorinated Vinyl Chloride Resin Composition 90 parts by weight of the chlorinated polyvinyl chloride obtained in (1) and 10 parts by weight of the vinyl chloride-based copolymer obtained in (2) were blended. 2 parts by weight of octyltin mercapto as a stabilizer, 1 part by weight of octyltin maleate polymer, 0.3 parts by weight of fatty acid ester as a lubricant, and 100 parts by weight of this mixture.
As an impact modifier, 10 parts by weight of methylmethacrylate-butadiene-styrene copolymer (MBS) was mixed and kneaded for 4 minutes on a mixing roll having a surface temperature of 190 ° C. A part of the obtained material sheet was crushed, and the outflow amount was measured by a Koka type flow tester. As a result, the outflow amount is 1.5 × 10 ^-2 c
It was c / s. The remaining material sheet is pressed with a press at 190 ℃.
After preheating for 1 minute, a test piece was prepared by pressing at a surface pressure of 75 kg / cm ² G for 4 minutes. The soft temperature, tensile strength, and impact value of this test piece were measured. The softening temperature and tensile strength were measured according to JIS K-6745 (hard vinyl chloride plate), and the impact value was measured according to JIS K-7111. As a result, the soft temperature was 93 ° C and the tensile strength was 570 kg / cm.
² (20 ° C.) and ^{450kg / cm 2 (60 ℃)} , and impact value 12
It was kg · cm / cm ² . The results are shown in the table below.

Example 2 Except that N-phenylmaleic acid imide was used in place of N-cyclohexylmaleic acid imide and the N-phenylmaleic acid imide unit was contained in the copolymer at a ratio of 15% by weight. A vinyl chloride copolymer was synthesized in the same manner as in 1. The average degree of polymerization of this vinyl chloride-based copolymer was 1,000. A chlorinated vinyl chloride resin composition was prepared in the same manner as in Example 1 except that 15 parts by weight of this vinyl chloride copolymer and 85 parts by weight of chlorinated polyvinyl chloride of Example 1 were blended. When the physical properties of this chlorinated vinyl chloride resin composition were measured by the same method as in Example 1, the outflow rate was 1.8 × 10 ^-2 cc / s, the flexible temperature was 93 ° C., the tensile strength was 580 kg / cm ² (20 ° C. ), And 460 kg / cm ² (60 ° C), and the impact value was 10 kg · cm / cm ² . The results are shown in the table below.

Example 3 Polyvinyl chloride having an average degree of polymerization of 1200 was used, and the chlorine content was changed.
A chlorinated polyvinyl chloride was prepared in the same manner as in Example 1 except that the amount was 62% by weight. A chlorinated vinyl chloride resin composition was prepared in the same manner as in Example 1 except that 80 parts by weight of this chlorinated polyvinyl chloride and 20 parts by weight of the vinyl chloride-based copolymer of Example 1 were blended. When the physical properties of this chlorinated vinyl chloride resin composition were measured by the same method as in Example 1, the outflow rate was 2.0 × 10 ^-2 cc / s, the flexible temperature was 94 ° C,
The tensile strength is 600kg / cm ² (20 ℃) and 490kg / cm ² (60
℃), and the impact value was 13 kg · cm / cm ² .

Example 4 Except that polyvinyl chloride having an average degree of polymerization of 800 was used,
Chlorinated polyvinyl chloride was synthesized in the same manner as in Example 1. On the other hand, as in Example 1, except that N-phenylmaleimide was used instead of N-cyclohexylmaleimide and the N-phenylmaleimide unit was contained in the copolymer at a ratio of 10% by weight. Similarly, a vinyl chloride copolymer was synthesized. The average degree of polymerization of this vinyl chloride copolymer was 1200. A chlorinated vinyl chloride resin composition was prepared in the same manner as in Example 1 except that 5 parts by weight of the vinyl chloride copolymer and 95 parts by weight of the chlorinated polyvinyl chloride were added. When the physical properties of this chlorinated vinyl chloride resin composition were measured by the same method as in Example 1, the outflow rate was 1.6 × 10 ^-2 cc / s, the softening temperature was 94 ° C., and the tensile strength was
620kg / cm ² (20 ℃), 500kg / cm ² (60 ℃), and the impact value was 16kg · cm / cm ² . The results are shown in the table below.

Comparative Example 1 Using chlorinated polyvinyl chloride prepared in the same manner as in Example 1, a chlorinated vinyl chloride resin composition was prepared without adding a vinyl chloride copolymer. When the physical properties of this chlorinated vinyl chloride resin composition were measured by the same method as in Example 1,
Outflow rate is 0.7 × 10 ^-2 cc / s, flexible temperature is 94 ℃, tensile strength is 590k.
The g / cm ² (20 ℃), 460kg / cm ² (60 ℃), and impact value were 8kg · cm / cm ² . The results are shown in the table below.

Comparative Example 2 Except that polyvinyl chloride having an average degree of polymerization of 350 was used,
Chlorinated polyvinyl chloride was prepared in the same manner as in Example 1. On the other hand, except that the average degree of polymerization is 1000 and the N-cyclohexylmaleimide unit is 15% by weight,
A vinyl chloride copolymer was synthesized in the same manner as in Example 1. A chlorinated vinyl chloride resin composition was prepared in the same manner as in Example 1 except that 15 parts by weight of this vinyl chloride copolymer and 85 parts by weight of the above vinyl chloride copolymer were blended. The physical properties of this chlorinated vinyl chloride resin composition are shown in Example 1.
When measured by the same method as above, the outflow was 3.5 × 10
^-2 cc / s, flexible temperature 94 ℃, tensile strength 560kg / cm ² (20 ℃),
And 450kg / cm ² (60 ℃), and the impact value is 2kg ・ cm / cm ²
Met. The results are shown in the table below.

Comparative Example 3 A chlorinated vinyl chloride resin composition was prepared in the same manner as in Example 1 except that the N-cyclohexylmaleimide unit was 40% by weight. When the physical properties of this chlorinated vinyl chloride resin composition were measured by the same method as in Example 1, the outflow rate was 0.8 × 10 ^-2 cc / s, the flexible temperature was 95 ° C., and the tensile strength was
The values were 640kg / cm ² (20 ℃) and 530kg / cm ² (60 ℃), and the impact value was 2kg · cm / cm ² . The results are shown in the table below.

Comparative Example 4 Example 1 was repeated except that N-phenylmaleic acid imide was used in place of N-cyclohexyl maleic acid imide and the N-phenylmaleic acid imide unit was contained in the copolymer in a proportion of 20% by weight. A vinyl chloride copolymer was synthesized in the same manner as in. The average degree of polymerization of this vinyl chloride copolymer is
It was 700. A chlorinated vinyl chloride resin composition was prepared in the same manner as in Example 1 except that 50 parts by weight of the vinyl chloride copolymer and 50 parts by weight of the chlorinated polyvinyl chloride of Example 1 were blended. When the physical properties of this chlorinated vinyl chloride resin composition were measured by the same method as in Example 1,
Outflow rate is 1.0 × 10 ^-2 cc / s, flexible temperature is 93 ℃, tensile strength is 590k.
g / cm ² (20 ℃), 450kg / cm ² (60 ℃), and impact value were 3kg · cm / cm ² . The results are shown in the table below.

Comparative Example 5 Polyvinyl chloride with an average degree of polymerization of 2500 was used to measure the chlorine content.
A chlorinated polyvinyl chloride was prepared in the same manner as in Example 1 except that the amount was 62% by weight. On the other hand, Example 1 was repeated except that N-phenylmaleic acid imide was used in place of N-cyclohexyl maleic acid imide and the N-phenylmaleic acid imide unit was contained in the copolymer at a ratio of 20% by weight. A vinyl chloride copolymer was synthesized in the same manner as in.
The average degree of polymerization of this vinyl chloride-based copolymer was 700. A chlorinated vinyl chloride resin composition was prepared in the same manner as in Example 1 except that 15 parts by weight of this vinyl chloride copolymer and 85 parts by weight of the above chlorinated polyvinyl chloride were blended. The physical properties of this chlorinated vinyl chloride resin composition are shown in Example 1.
When measured by the same method as above, the outflow amount is 0.3 × 10
^-2 cc / s, flexible temperature 95 ℃, tensile strength 610kg / cm ² (20 ℃),
And 480kg / cm ² (60 ℃), and the impact value is 11kg ・ cm / cm
^{Was 2} . The results are shown in the table below.

Comparative Example 6 Example 6 was repeated except that N-phenylmaleic acid imide was used in place of N-cyclohexylmaleic acid imide and the N-phenylmaleic acid imide unit was contained in the copolymer in a proportion of 20% by weight. A vinyl chloride copolymer was synthesized in the same manner as in 1. The average degree of polymerization of this vinyl chloride copolymer was 400. A chlorinated vinyl chloride resin composition was prepared in the same manner as in Example 1 except that 20 parts by weight of the vinyl chloride copolymer and 80 parts by weight of the chlorinated polyvinyl chloride of Example 1 were blended. When the physical properties of this chlorinated vinyl chloride resin composition were measured by the same method as in Example 1, the outflow rate was 2.3 × 10 ^-2 cc / s, the flexible temperature was 94 ° C, and the tensile strength was 580 kg / cm ² (20 ° C. ), And 440 kg / cm ² (60 ° C), and the impact value was 6 kg · cm / cm ² . The results are shown in the table below.

Comparative Example 7 A vinyl chloride homopolymer was synthesized in the same manner as in Example 1 except that N-cyclohexylmaleimide was not used. The average degree of polymerization of this vinyl chloride homopolymer is
It was 1000. A chlorinated vinyl chloride resin composition was prepared in the same manner as in Example 1 except that 10 parts by weight of the vinyl chloride homopolymer and 90 parts by weight of the chlorinated polyvinyl chloride of Example 1 were blended. When the physical properties of this chlorinated vinyl chloride resin composition were measured by the same method as in Example 1,
Outflow rate is 3.0 × 10 ^-2 cc / s, flexible temperature is 84 ℃, tensile strength is 580k.
The g / cm ² (20 ℃) and 320kg / cm ² (60 ℃), and the impact value were 15kg · cm / cm ² . The results are shown in the table below.

As is clear from the examples and comparative examples, the chlorinated vinyl chloride resin composition of the present invention has good heat resistance and excellent processability. High impact resistance. Average degree of polymerization is 35
A chlorinated vinyl chloride resin composition using 0 chlorinated polyvinyl chloride, a chlorinated vinyl chloride resin composition using a vinyl chloride copolymer having an average degree of polymerization of 400, and an N-cyclohexylmaleimide unit All of the chlorinated vinyl chloride resin compositions using 40% by weight of vinyl chloride copolymer have poor impact resistance. A chlorinated vinyl chloride resin composition using chlorinated polyvinyl chloride having an average degree of polymerization of 2500,
The resin composition containing no vinyl chloride copolymer (mainly chlorinated polyvinyl chloride) has a low outflow value,
Workability is poor. Even if 50 parts by weight of a vinyl chloride-based copolymer is added to 50 parts by weight of chlorinated polyvinyl chloride, a composition with low impact resistance is obtained. The composition containing the vinyl chloride homopolymer has good processability but lacks heat resistance.

(Effect of the Invention) The chlorinated vinyl chloride resin composition of the present invention is
-A vinyl chloride-based copolymer having a substituted maleic acid imide unit is blended with chlorinated polyvinyl chloride, so that it has good heat resistance, excellent workability, and high impact resistance. The workability is remarkably improved while maintaining the excellent heat resistance and impact resistance of chlorinated polyvinyl chloride. As a result, the chlorinated vinyl chloride resin composition of the present invention is suitably used as a thermoplastic material for hard molded products such as pipes, plates and calender films by the steps of extrusion, injection, compression or transfer molding. .

Claims (2)

[Claims] 1. A chlorinated polyvinyl chloride obtained by post-chlorinating polyvinyl chloride having an average degree of polymerization of 400 to 2000.
95 parts by weight, and (2) an average degree of polymerization 500 having 70 to 95% by weight of vinyl chloride units and 5 to 30% by weight of N-substituted maleimide units.
A chlorinated vinyl chloride resin composition containing from 5 to 30 parts by weight of a vinyl chloride copolymer of from 1500 to 5 parts by weight. 2. The chlorine content of the chlorinated polyvinyl chloride is
The chlorinated vinyl chloride resin composition according to claim 1, which is 60 to 70% by weight.