JP2004263080A - Vinyl chloride based-resin composition and its molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a vinyl chloride-based resin composition having a good moldability and giving a molded article excellent in appearance and a strength. <P>SOLUTION: The vinyl chloride-based resin composition comprises a vinyl chloride-based resin, at least an acrylate-based copolymer and a reactive compatibilizer added to the resin. The quantity of the reactive compatibilizer added is not more than the quantity of the acrylate-based copolymer. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a vinyl chloride resin composition, and more particularly to a vinyl chloride resin composition capable of improving impact strength and tensile strength by a reaction during molding and a molded article thereof.
[0002]
[Prior art and its problems]
In a vinyl chloride resin composition, a core / shell type impact modifier, for example, ABS, MBS resin or acrylic rubber, is usually added to the vinyl chloride resin for the purpose of improving impact strength, and molded by various molding methods. You.
However, while the core / shell type impact modifier is effective in improving impact strength, it is known that on the other hand, there is a problem that tensile strength, particularly tensile strength, is reduced.
When such a core / shell type impact modifier is mixed with a polyvinyl chloride resin and molded, the impact modifier is not chemically bonded to polyvinyl chloride, so that the impact strength cannot be increased with the added amount to secure the tensile strength. Not expressed.
On the other hand, there is a copolymer obtained by previously copolymerizing a core-shell type impact modifier with polyvinyl chloride. However, in this case, there is a problem that the polymerization process of the polyvinyl chloride copolymer becomes complicated and industrial production is inferior. Further, there is known a technique in which hydrazine is added to a dispersion of a chlorinated vinyl chloride-based resin in a polymerization step while blowing nitrogen gas to form a chemical bond in order to improve thermal stability (for example, Patent Document 1). 1).
[0003]
However, when molding a vinyl chloride resin, there is no known technology that combines a specific additive and performs chemical bonding at a melting temperature to satisfy both the tensile strength and the impact strength of a molded product. Was.
[0004]
[Patent Document 1]
JP-A-5-239119 [0005]
[Means for Solving the Problems]
The present invention has found a vinyl chloride-based resin composition that can solve the above problems, and the gist of the present invention is as follows:
A vinyl chloride resin comprising at least an acrylate copolymer and a reactive compatibilizer added thereto, wherein the amount of the reactive compatibilizer is equal to or less than the acrylate copolymer. In the base resin composition.
[0006]
As the reactive compatibilizer, a hydrazine compound can be suitably used, and it is preferable to add the hydrazine compound in an amount of 0.1 to 2.0 parts by weight based on 100 parts by weight of the vinyl chloride resin.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
As the vinyl chloride resin (hereinafter referred to as "PVC") in the present invention, a normal polyvinyl chloride homopolymer can be used, and a small amount of a copolymerizable monomer such as vinyl acetate, vinylidene chloride, and styrene is copolymerized. Post-chlorinated products of copolymers and these resins can also be used. The average polymerization degree of this PVC can be suitably used in the range of about 600 to 1,700, preferably about 820 to 1,450.
[0008]
An ordinary stabilizer is added to the PVC, and as the stabilizer, an organotin-based stabilizer having low toxicity, for example, a dioctyltin compound, a monobutyltin compound, and a mixture thereof can be preferably used. The stabilizer may be used in an amount of 0.2 to 3.0 parts by weight, preferably 0.3 to 2.5 parts by weight, per 100 parts by weight of PVC.
[0009]
In the present invention, it is necessary to use a specific impact modifier for the PVC, and an acrylate copolymer is used. Examples of the acrylate copolymer include acrylic rubber-acrylate copolymer, butadiene rubber-acrylate copolymer, (butadiene-styrene) rubber-acrylate copolymer, (acryl-silicone rubber) -acrylate copolymer, and (acrylic). -Butadiene-styrene rubber) -acrylate copolymer.
It is necessary to use the acrylate copolymer in the range of 4.0 to 15.0 parts by weight, preferably 5.0 to 8.0 parts by weight, based on 100 parts by weight of PVC. If the amount is less than 4 parts by weight, the resulting molded article will have poor impact strength, and if it exceeds 15 parts by weight, the tensile strength will be poor.
[0010]
In the present invention, it is necessary to add a reactive compatibilizer together with the acrylate-based copolymer, and physical properties can be improved by reacting at a melting temperature during molding. As the reactive compatibilizer, a hydrazine-based compound can be suitably used. The following compounds can be used as the hydrazine-based compound.
(1) Hydrazine hydrate, hydrazine salt compound Hydrazine hydrate, hydrazine hydrochloride, hydrazine hydrobromide, hydrazine sulfate, hydrazine phosphate, hydrazine carbonate, etc. (2) Alkyl hydrazine compound benzyl hydrazine, butyl hydrazine hydrochloride, isopropyl hydrazine sulfate , Methyl hydrazinoacetate hydrochloride, etc.
{Circle around (3)} Hydrazide compounds adipic dihydrazide, zebacic dihydrazide, todecanediohydrazide, isophthalic dihydrazide, propionic hydrazide, salicylic hydrazide, hydroxynaphthoic hydrazide, carbohydrazide, thiocarbohydrazide, oxybisbenzenesulfonyl hydroxide Aminopolyacrylamide, etc. 4) Pyrazole compound 5) Triazole compound 6) Tetrazole compound 7) Thiadiazole compound 8) Pyridazine compound 9) Azo compound [0012]
The hydrazine compound is preferably used in an amount of 0.1 to 5.0 parts by weight, preferably 0.3 to 2.0 parts by weight, per 100 parts by weight of PVC. If the amount is less than 0.1 part by weight, the resulting molded article has poor tensile strength, and if it exceeds 5 parts by weight, there is a problem that the thermal stability tends to be inferior.
Here, the number of parts to be added of the hydrazine-based compound must be equal to or less than the above-mentioned acrylate-based copolymer. There is a problem that the cross-linking of the base resin itself is promoted, and the molding process becomes difficult due to an increase in viscosity and thermal decomposition.
[0013]
In the composition of the present invention, a metal soap such as calcium stearate, a polyhydric alcohol such as dipentaerythritol, a coloring agent, a lubricant, and an ultraviolet absorber can be appropriately added.
[0014]
The vinyl chloride resin composition according to the present invention can be prepared by a conventionally known method. For example, a method of weighing a predetermined amount of a vinyl chloride resin, a hydrazine compound, an acrylate copolymer, and further, if necessary, other resin additives, and mixing them with a mixer to form a dry blend, A method of kneading the form with a kneading machine is exemplified.
[0015]
There are no particular limitations on the mixers and kneaders that can be used, and examples thereof include conventionally known mixers such as a ribbon mixer, a change can mixer, and a super mixer (Henschel mixer). Examples of the kneading machine include a mixing roll, a Banbury mixer, a blade-type kneading machine, a high-speed twin-screw continuous mixer, and an extruder-type kneading machine.
[0016]
The vinyl chloride-based resin composition according to the present invention can be used to produce a desired product or part having excellent transparency by a conventionally known molding method such as extrusion molding, injection molding, and compression molding. As products and parts, extruded products such as corrugated plates, flat plates, and pipes can be suitably manufactured.
[0017]
【Example】
Hereinafter, examples of the present invention will be described, but the present invention is not limited thereto.
Common formulation Vinyl chloride resin (degree of polymerization 1300) 100 parts by weight tin stabilizer (dioctyltin mercapto) 1 part by weight lubricant (polyethylene wax / dipentaerythritol stearate = 1/1 mixed lubricant One pack) 1 part by weight chlorinated polyethylene 1.5 parts by weight Colorant 0.3 part by weight [0018]
[Example 1]
5 parts by weight of an acrylic impact modifier (silicone acrylic: "METABLEN S2001" manufactured by Mitsubishi Rayon Co., Ltd.) and 0.5 part of a hydrazine compound (adipic dihydrazide: "ADH" manufactured by Nippon Hydrazine Co., Ltd.) were added to the above-mentioned common formulation. Parts by weight were blended.
After mixing 1 kg of the above compound with a Henschel mixer, the mixture was kneaded at 190 ° C. for 5 minutes using two rolls to obtain a sheet having a thickness of 0.5 mm. The obtained sheet was heated and pressed at 100 kg / cm ² at 195 ° C. for 15 minutes using a heating press machine to obtain 1 mm and 5 mm thick samples. The impact strength and tensile strength were measured using the obtained sample.
As a result, the impact strength was 97 cm and the tensile strength was 46.0 MPa.
Usually, an impact strength of 85 cm or more and a tensile strength of 44 MPa or more can be said to be good as an impact-resistant hard vinyl chloride resin molded article.
[0019]
In addition, the measuring method of an impact strength and a tensile strength is as follows.
-Impact strength Measured according to JIS7211. Using a sample having a thickness of 1 mm, a weight drop test was performed in a 2 Kg tip R = 5 mm, -10 ° C. atmosphere, and a 50% breaking height was measured.
-Tensile strength Measured according to JIS K 6745. Sample thickness 5 mm, measurement temperature 23 ° C.
[0020]
[Example 2]
A sample was obtained in the same manner as in Example 1 except that acetone thiosemicarbazone ("ATS" manufactured by Nippon Hydrazine Co., Ltd.) was used instead of the hydrazine compound used in Example 1. The impact strength and the tensile strength were measured using the obtained sample.
As a result, the impact strength was 87 cm and the tensile strength was 46.5 MPa.
[0021]
[Comparative Example 1]
A sample was obtained in the same manner as in Example 1 except that the hydrazine compound was not used in the composition of Example 1. The impact strength and the tensile strength were measured using the obtained sample.
As a result, the impact strength was 80 cm, and the tensile strength was 45.9 MPa, which was low.
[0022]
[Comparative Example 2]
The same content as in Example 1 except that the acrylic impact modifier (silicone acrylic: "METABLEN S2001" manufactured by Mitsubishi Rayon Co., Ltd.) was changed to 7 parts by weight and the hydrazine compound was not used in the composition of Example 1. A sample was obtained. The impact strength and tensile strength were measured using the obtained sample.
As a result, the impact strength was 85 cm and the tensile strength was 41.0 MPa. The impact strength was good, but the tensile strength was low.
[0023]
【The invention's effect】
As described above, according to the resin composition of the present invention, it is excellent in moldability, appearance and strength of the obtained molded product, and is applicable to production of various molded products such as flat plates, pipes, and extruded products. Is big.

Claims (4)

A vinyl chloride resin, wherein at least an acrylate copolymer and a reactive compatibilizer are added to the vinyl chloride resin, and the amount of the reactive compatibilizer added is equal to or less than the acrylate copolymer. -Based resin composition. The vinyl chloride resin composition according to claim 1, wherein the reactive compatibilizer is a hydrazine compound. 3. The vinyl chloride resin composition according to claim 1, wherein 0.1 to 5.0 parts by weight of a reactive compatibilizer is added to 100 parts by weight of the vinyl chloride resin. A molded article obtained by extruding the vinyl chloride resin composition according to any one of claims 1 to 3.