JPH06287385A - High-elasticity resin composition of improved low-temperature rigidity - Google Patents

Abstract

PURPOSE:To provide the title composition scarcely changing in rigidity at low temperatures, having high rigidity and not suffering from blooming even on long-term weather exposure. CONSTITUTION:The composition comprises 100 pts.wt. vinyl chloride resin of an average degree of polymerization of 1500 or above, 10-300 pts.wt. acrylonitrile/butadiene copolymer containing 20-50wt.% acrylonitrile and having a degree of partial crosslinking of 10-95%, 10-60 pts.wt. low-temperature plasticizer, 30-200 pts.wt. general-purpose plasticizer and 0.02-2 pts.wt. antioxidant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition used for, for example, automobile glass run, trunk and bonnet packing material, or packing material for building materials,
In particular, the present invention relates to a high-elasticity resin composition that exhibits little change in rigidity even when used under low temperature environmental conditions.

[0002]

2. Description of the Related Art Soft vinyl chloride resin is easy to process,
Moreover, since it is cheap, the molded products are widely used from daily sundries to automobile parts.
In recent years, it has been used as a packing material for automobiles or building materials by adding an additive such as a plasticizer to the above resin used for such an application.

[0003]

However, in the above conventional technique, when used as a packing material or the like, the rigidity of the vinyl chloride resin used becomes high at low temperatures (particularly at temperatures of 0 ° C. or lower). There is a drawback that the packing material itself becomes hard and its elastic function is deteriorated, and its role cannot be fully fulfilled. For example, when used as a packing material for automobiles or the like, it becomes hard at 0 ° C. or lower and becomes elastic, so that there is a disadvantage that water leakage and rattling due to improper fixing of glass during traveling occur.

Therefore, such a drawback can be improved by using a plasticizer having a relatively low temperature property or adding a secondary plasticizer having a further low temperature property to the compounded plasticizer. However, the above-mentioned drawbacks could not be solved because the plasticizer was blown out or cracked due to deterioration of weather resistance.

Therefore, the present invention is intended to solve the above-mentioned problems of the prior art, and has a small change in rigidity at low temperatures, high elasticity, and low temperature rigidity that does not cause blowout even when exposed to long-term weather resistance. It is an object to provide a highly elastic resin composition having improved

[0006]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that vinyl chloride-based resin contains acrylonitrile-butadiene copolymer, cold-resistant plasticizer, general-purpose plasticizer. The inventors have completed the invention by finding that the above problems can be improved by containing a specific amount of an antioxidant. That is, the present invention comprises: A) 100 parts by weight of a vinyl chloride resin having an average degree of polymerization of 1500 or more; B) Acrylonitrile-butadiene copolymer containing 20 to 50% by weight of acrylonitrile and having a degree of partial crosslinking of 10 to 95%. To 300 parts by weight, C) 10 to 60 parts by weight of cold-resistant plasticizer, D) 30 to 200 parts by weight of general-purpose plasticizer, and E) 0.02 to 2 parts by weight of an antioxidant, improving low temperature rigidity. The gist is the high elasticity resin composition described above.

The present invention will be described in detail below. The vinyl chloride resin used as the component A constituting the highly elastic resin composition of the present invention has an average degree of polymerization of 1500 or more, preferably 2000 to 5000. If it is less than 1500, the elasticity is lowered and there is a problem in compression set, and if it exceeds 8,000, the meltability is very poor and there is a problem in workability, which is not preferable.

Examples of the vinyl chloride resin include those obtained by suspension polymerization, emulsion polymerization, or bulk polymerization of a monomer mixture of vinyl chloride and a comonomer copolymerized therewith. The vinyl monomers to be polymerized include vinyl acetates such as vinyl acetate, vinyl propionate and vinyl laurate, acrylic acid esters such as methyl acrylate, ethyl acrylate and butyl acrylate, and methacrylic acid such as methyl methacrylate and ethyl methacrylate. Examples thereof include acid esters, fumarate acid esters such as dibutyl fumarate and diethyl fumarate.

In the highly elastic resin composition of the present invention, the acrylonitrile-butadiene copolymer used as the component B is added in order to impart / improve thermal deformation and rubber elasticity of the resulting resin composition. Is acrylonitrile having a content of 20 to 50% by weight and a degree of partial crosslinking of 10 to 95%. When the content of this acrylonitrile is less than 20% by weight, heat resistance and compatibility with vinyl chloride resin deteriorate, and when it exceeds 50% by weight, hardness becomes high and impact resilience and flexibility deteriorate. 20 to 50% by weight, preferably 30 to 4
It is in the range of 5% by weight. The Mooney viscosity at this time is 30 to 88 ML1 + 4 (100 ° C.), preferably 40 to 70 ML1 + 4 (100 ° C.).

Thus, the acrylonitrile-butadiene copolymer containing a specific amount of acrylonitrile has a degree of partial cross-linking of less than 10% and does not have a degree of cross-linking sufficient to improve heat deformation, but exceeds 95%. The degree of partial cross-linking is 10 to 95%, preferably 6 because it is impossible to polymerize.
It is in the range of 0 to 90%.

The degree of partial cross-linking was determined by adding 100 g of acrylonitrile-butadiene copolymer to 100 cc of tetrahydrofuran (THF), stirring the mixture at 23 ° C. for 24 hours and mixing, and then mixing the mixed solution with 200 mesh filter paper. It is expressed in% of the residue which is filtered at 60 ° C. and dried at 60 ° C. for 15 hours.

If the blending ratio of the acrylonitrile-butadiene copolymer as the component B is less than 10 parts by weight with respect to the above vinyl chloride resin 100 resin, the heat deformation and rubber elasticity imparting effect of the obtained molded article will be insufficient. If the amount is more than 300 parts by weight, the flowability will deteriorate, and the resulting molded article will have irregularities on the surface, resulting in poor appearance and poor processability. 300 parts by weight, preferably 20-
It is desirable to add 250 parts by weight.

In the highly elastic resin composition of the present invention, the cold-resistant plasticizer used as the component C is an aliphatic dibasic acid ester, and examples thereof include dioctyl sebacate, dioctyl azelate, dioctyl adipate, diisooctyl adipate, Examples thereof include dibutyl sebacate and dioctyl tetrahydrophthalate, which are used in one kind or in two or more kinds, and with respect to 100 parts by weight of the above vinyl chloride resin,
Cold resistant plasticizer 10 to 90 parts by weight, preferably 15 to 75
Parts by weight are added. If the amount added is less than 10 parts by weight, the low-temperature rigidity effect will not be obtained, and if it exceeds 90 parts by weight, blowing out of the plasticizer cannot be suppressed.

Examples of general-purpose plasticizers used as the component D include phthalic acid esters and the like. Examples thereof include dioctyl phthalate, diisooctyl phthalate, diisononyl phthalate, diisodecyl phthalate, and the like, and 100 parts by weight of the above vinyl chloride polymer. On the other hand, the general-purpose plasticizer is added in an amount of 30 to 200 parts by weight, preferably 50 to 150 parts by weight. If the added amount is less than 30 parts by weight, it is too hard to obtain high elasticity, and there is a problem that sufficient elasticity cannot be obtained only with the plasticizer of the component C. If it exceeds 200 parts by weight, the vinyl chloride resin However, there is a problem that the plasticizer of the C component is blown out, which is close to the limit of the plasticizer absorption capacity.

Examples of the antioxidant used as the E component include amine-based, quinoline-based, monophenol-based, bis-, tris-, polyphenol-based, thiobisphenol-based, and phosphite-based antioxidants. 0.02 to 2 parts by weight, preferably 0.03 to 1.5 parts by weight, is added to the vinyl chloride resin. If the addition amount is less than 0.02 part by weight, the effect of preventing deterioration is not obtained, and 2
If the amount is more than parts by weight, the effects are balanced and the cost is increased.

The highly elastic resin composition of the present invention has the above-mentioned 5
In addition to the ingredients, stabilizers can be added if desired. The stabilizer may be any one as long as it does not detract from the weather resistance of vinyl chloride. In addition to this stabilizer, a UV absorber that can be used for vinyl chloride,
Inorganic filler, pigment, lubricant, processing aid, foaming agent, flame retardant,
You may mix additives, such as a smoke-proofing agent, a mildew-proofing agent, and an antibacterial agent, as needed.

The highly elastic resin composition of the present invention comprising these components is mixed and blended by a usual means such as a Henschel mixer and a ribbon blender, and molded and processed by a usual extruder such as an extruder and a roll Banbury mixer. To be done.

[0018]

【Example】

Examples 1 to 4 and Comparative Examples 1 to 7 A resin composition containing the components shown in Table 1 was subjected to a physical property test by the following methods, and the results are shown in Table 1. The details of each component used are as follows.

(Component) A. Vinyl chloride resin (manufactured by Shin-Etsu Chemical Co., Ltd., average degree of polymerization: 2500) B-1. Acrylonitrile-butadiene copolymer (Chemical gum P-83, Goodyear Co., containing 33% by weight of acrylonitrile, degree of partial crosslinking 86%) B-2. Acrylonitrile-butadiene copolymer (NBR, manufactured by Goodyear, containing 30% by weight of acrylonitrile, degree of partial crosslinking 6%) C.I. General-purpose plasticizer (dioctyl phthalate [DOP]) D. Cold-resistant plasticizer (dioctyl sebacate [DOS]) E. Antioxidant (Bisphenol Antioxidant) F. Stabilizer (Ba-Zn stabilizer)

Evaluation Test Method A compound was prepared by drying up to 90 ° C. with a 20 L super mixer, and using a 6 inch roll, the mixture was heated at 140 ° C. for 8 hours.
A roll sheet was kneaded for a minute, and this was pressed with a press at a temperature of 170 ° C. for 8 minutes to form a sheet having a thickness of 2 mm, which was used as a test sample.

(Workability test) The compound prepared by the above method was kneaded with a 16-inch roll and then pelletized using a sheet pelletizer. The pellets were molded into a sheet having a thickness of 2 mm and a width of 20 mm with an extruder having a compression ratio of 30 mmL / D26 of 3.0, and the melt elongation and the appearance were evaluated as described below. ◎: Smooth appearance and melt elongation ◯: Smooth appearance and slightly inferior or low melt elongation ×: Poor appearance and no melt elongation

(Blow-out) The test sample described above
Leave for 1000 hours at 3 ° C and observe the surface for stickiness.
It evaluated as follows. ⊚: No stickiness ◯: Some stickiness X: Large stickiness.

(Weathering resistance blowout) The test sample described above was heated at 63 ° C. for 8 hours using a sunshine weatherometer.
The stickiness of the surface when irradiated for 00 hours was observed and evaluated as follows. ⊚: No stickiness ◯: Some stickiness X: Large stickiness.

(Weather resistance crack) The test sample described above was heated to 8 ° C. at 63 ° C. using a sunshine weatherometer.
The stickiness of the surface when irradiated for 00 hours was observed and evaluated as follows. ⊚: No cracks occurred ◯: Some cracks were observed ×: Large number of large cracks were observed

(Compression Set) The above-mentioned test sample was subjected to JIS K-6301 at 70 ° C. for 22 hours to evaluate the compression set.

(Low Temperature Rigidity) The above-mentioned test sample was tested at -40 ° C. according to JIS K-6301 to evaluate the low temperature rigidity.

[0027]

[Table 1]

[0028]

According to the highly elastic resin composition of the present invention, since each component is blended in a specific ratio as described above,
Since the change in rigidity at low temperature is small, it has high elasticity, and it can be satisfied even in the physical property tests in the examples,
It is possible to provide a highly elastic resin composition that is extremely good in practical use.

Claims (1)

[Claims] 1. A) 100 parts by weight of vinyl chloride resin having an average degree of polymerization of 1500 or more, B) Acrylonitrile-butadiene copolymer containing 20 to 50% by weight of acrylonitrile and having a degree of partial crosslinking of 10 to 95%. 300 parts by weight, C) 10 to 60 parts by weight of cold-resistant plasticizer, D) 30 to 200 parts by weight of general-purpose plasticizer, E) 0.02 to 2 parts by weight of antioxidant, A highly elastic resin composition having improved low temperature rigidity.