JPS61275342A - Antproofing vinyl chloride resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin compsn. which can keep potent antproofness and can prevent buildings, cables from being attacked by termite, by incorporating an org. phosphorus insecticide in a vinyl chloride resin. CONSTITUTION:0.01-10wt%, pref. 0.05-5wt% isopropyl 2-[ethoxy(isopropylamino)thiophosphoryloxy]benzate (general name: isophenphos) is incorporated in a vinyl chloride resin compsn. In plastics mainly composed of vinyl chloride resin, a stabilizer is usually used to prevent the resin from releasing hydrochloric acid. When a stabilizer contg. Ba, Cd or Pb is used, the antproofing effect of the compsn. of the present invention is particularly remarkable. Examples of such stabilizers are barium stearate and tribasic lead sulfate.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a termite-proofing vinyl chloride resin composition, and its purpose is to maintain strong termite-proofing properties and prevent termites from building houses, buildings, etc. floorboards, nosifs, tapes, tubes,
An object of the present invention is to provide a termite-proof vinyl chloride resin composition that can prevent damage to cables, etc. over a long period of time.

[Conventional technology]

Vinyl chloride resin is inexpensive and has excellent physical and chemical properties, so it is used in large quantities in a wide range of fields, from daily necessities and headgear to agricultural and industrial materials, and architectural and civil engineering materials.

Among them, for example, electric wire cables buried in the ground,
These include various types of pipes, the tapes that cover them, the heat shrink tubes and adhesives used to connect them, and many other items that are used at least partially in contact with or close to soil.

However, despite its excellent physical and chemical properties, this vinyl chloride resin has the disadvantage of being eaten by termites when used in contact with or close to soil. In fact, there have been many reports of accidents in which the covering portion of a vinyl chloride resin-coated electric wire has been damaged by termites, and metal corrosion has progressed from that portion, making it impossible to conduct electricity or communicate.

Termites are harmful pests that feed on all kinds of natural and synthetic organic materials, including wood, trees, crops, textiles, leather, plastics, and rubber, and sometimes even damage metals such as lead. It is.

Methods for preventing termite damage are adopted depending on the type of termite, the environment in which termites live, etc., but basically, (a) imparting termite-proofing properties to the object itself; Methods can be roughly divided into two: (b) providing anti-termite properties to the vicinity of the object.

In other words, the method (a) involves imparting anti-termite properties to the object itself, or making the object exhibit anti-termite properties through its material structure; for example, by creating a layer containing an anti-termite agent, Examples include methods such as coating or coating with a material (for example, metal such as copper) that has termite-proofing properties itself. Among these methods, from the viewpoint of processability and cost of the object, particularly the molded object, the most commonly adopted method has been to incorporate termiticides such as thorin-based drugs and chlordane into the material itself.

However, it became clear that Thorin-based drugs were harmful to humans and animals and caused environmental pollution, and on October 2, 1981,
Its use was prohibited by Japanese Cabinet Order No. 302. In addition, like these Torine agents, chlordane, which is widely used as a termite control agent, also has similar problems, and on December 2, 1982,
According to Japanese Cabinet Order No. 246, substances with a content of 6% or less are designated as deleterious substances, and their use is subject to regulations.

In addition to torin-based drugs, for example, plastics containing extracts of hinokiasunaro wood (Utility Model Publication No. 52-14623
), plastics containing 10% by weight or more of creosote oil (Japanese Patent Publication No. 57-30787), PVC containing polyester plasticizers (molecular weight 3000 or more) (Japanese Patent Publication No. 55-8810), indicated by a lidene group Resin composition containing 5 to 50 parts by weight of one or more compounds (Utility Model Application No. 57-140016)
, P mixed with fenitrothion or phoxim or chlorpyrifos and zinc octylate or zinc persate, etc.
VC (Japanese Unexamined Patent Publication No. 58-25012 or Unexamined Japanese Patent Application No. 58-14
No. 292'1, JP-A-58-169810), etc. are known.

However, it goes without saying that termiticides that are mixed into electric wire cables, pipes, tubes, tapes, etc. that are buried in the ground must maintain long-term termite-proofing properties when mixed with vinyl chloride resin. Must be. In particular, heating during resin molding and processing, specifically 140 to 220°C1
The anti-termite component should not be decomposed or volatilized even by heating for several minutes to one hour, the resin should not bloom even after molding, and the physical and chemical properties such as electrical insulation should not be deteriorated.

However, a vinyl chloride resin composition that satisfies all of these conditions has not yet appeared.

[Means to solve the problem]

As a result of intensive research to solve the above-mentioned problems, the present inventors have discovered that a vinyl chloride resin containing a specific organic phosphorus agent has high termite resistance over a long period of time, and can be molded at high temperatures. Based on this finding, we have developed the termite-proof vinyl chloride resin composition of the present invention. completed. That is, the present invention 1 is a termite-proofing vinyl chloride resin composition containing isopropyl-2-[ethoxy(isopropylamino)thiophosphoryloxy]benzoate.

The isopropyl-2-[ethoxy(isopropylamino]thiophosphoryloxy]benzoate according to the present invention is commonly referred to as isofenphos.

In the present invention, this infenphos is generally 0.01 to 10% by weight, preferably 0.01 to 10% by weight, preferably 0.
．． 05 to 5% by weight.

For plastics based on vinyl chloride resin (PVC), to prevent dehydrochlorination of these resins, for example, Ba-Zn stabilizers (including liquid and solid) are used as stabilizers.
, tin-based stabilizer, Zn-based stabilizer, Cd-Zn-based, Mg-
Many seed oils such as Zn-based, l;l:a-Zn-based, and other epoxidized soybean oils, or mixtures thereof, are used depending on their respective applications.

The present inventors have found that among these stabilizers, when one containing Ba, Cd or PB is used, the termite-proofing effect of the resin is further enhanced. That is, those that have vinyl chloride resin as the main ingredient and contain Ba or Pb as a stabilizer,
The termite-preventing vinyl chloride composition containing the above-mentioned isopropyl-2-[ethoxy(isopropylamino)thiophosphoryloxy]benzoate as a termite-preventing agent exhibits particularly excellent termite-proofing properties.

Specific examples of stabilizers containing Ba, Cd or Pb include barium stearate, tribasic lead sulfate, lead stearate, dibasic lead stearate, tribasic lead phosphite, basic sulfite. Examples include lead. The blending ratio of this stabilizer to the vinyl chloride resin composition is usually 0.1 to 10% by weight, preferably 1 to 5% by weight. These stabilizers are mixed with PVC, plasticizers, and fillers to prepare PVC compounds. Termiticides may be mixed into PVC compounds along with plasticizers, but
Generally, it is preferable to mix the PvC compound when heating and molding the PvC compound.

The vinyl chloride resin composition of the present invention has PVC as its main ingredient, and can be molded by conventionally known plastic molding methods, such as extrusion, injection, blow molding, and calender molding methods. In addition, it should be suitable for each shape to be molded (PVC,
Similarly, there is no problem in adding other compounding agents other than stabilizers and termiticides, such as lubricants, plasticizers, colorants, etc., which are usually added.

As a plasticizer, DOP (dioctyl phthalate), DI
DP (diisodecyl heptatarate, matearic acid, etc.) that is generally used for PvC can be used, and can be selected depending on the purpose.

When obtaining a heat-shrinkable tube from the composition of the present invention, first, the composition of the present invention is extruded to make a tube-molded product.
This is subjected to chemical crosslinking or electron beam irradiation crosslinking. When PVC is crosslinked by electron beam irradiation, a required amount (for example, 2 to 10 parts by weight) of a polyfunctional monomer may be blended in advance.

The crosslinked tube molded product is heated to a temperature higher than the softening point or crystal melting point of the resin composition to mechanically expand and expand the diameter of the tube molded product. Next, by cooling the expanded state to room temperature, a heat-shrinkable tube is obtained.

Example 1 The anti-termite vinyl chloride resin composition of the present invention containing infenphos not only has anti-termite effects, but also has superior anti-termite properties to electric wires, cables, etc., compared to those using other termiticides. The following shows that it has excellent electrical properties.

(Test termiticide) Table 1 shows the test termiticides used.

Table 1: Chlorbisphos 2 Prothiophos 3 Fenitrothion 4 Isofenphos Regarding the termiticide properties of the drugs listed in Table 1, the following termicidal efficacy test was conducted, and the results shown in Table 2 were obtained.

Anticidal efficacy test (knockdown test) (a) Diluent: acetone, drug concentration 0.1% and 1
%.

(b) Test termites: Termite worker ants (c) Test method 2. Evaluate the termiticidal properties of the drug based on the mortality rate after 24 hours (25'C) according to the method specified by the Japan Termite Countermeasures Association. did.

(Unit: Mortality rate after 24 hours) (Test sheet) PVC (degree of polymerization: approximately 1100-1300)
100 parts plasticizer (phthalate ester) 5 parts filler (heavy calcium carbonate) 30 parts stabilizer (tribasic lead sulfate) 5 parts Yosuru PvC
The termiticide shown in Table 1 is mixed with a plasticizer into the compound, mixed with a roll at 160℃ for about 10 minutes, taken out in the form of a 1-mark thick sheet, further preheated at 160℃ for 10 minutes, and pressed for 1 hour.
18anx with 0 minute press processing and 3% termiticide added
A 17an sample sheet was obtained. This IM-thickness PvC sheet was coated on 30 mm square pine sapwood, the overlapping portions and end portions were completely sealed with adhesive tape with metal tape, and the sheet was subjected to a field test. Field tests were conducted for three years, and the results are shown in Table 3.

Table 3 Table 4 also shows the electrical properties (insulation resistance) of the PVC sheets obtained in the same manner.

Table 4 First of all, it can be seen from Table 3 that Prothiophos has sufficient anti-termitic and termiticidal properties as a drug itself, but in a field test, even a PVC sheet with 3% additive was penetrated through one thickness. Oops. Therefore, no anti-termite effect can be expected even if it is mixed into the covering for electric wires and cables.

Chlorpyrifos is added to 3% PVC as shown in Table 4.
The insulation resistance value of the sheet decreased to about 171,433 compared to the additive-free product (a decrease of more than 8 orders of magnitude), making it unsuitable as a sheath material for electric wires and cables.

In this respect, isofenphos and fenitrothion only show a two-digit decrease, and can maintain the J012Ω/saliva, which is generally required as a sheath material for electric wires and cables.

(Cable extrusion test) A PvC compound with the same composition as the test sheet was extruded using an extruder as a sheath material, and crosslinked polyethylene P
A vC sheath cable (3CX22SQ) was obtained. Collect an appropriate amount of sample from the PvC sheath of this cable,
The remaining amount of added termiticide in the PvC compound was determined.

The results are shown in Table 5.

Table 5 (Unit: Residual Rate %) As shown in Table 5, most of the added amount of fenitrothion is decomposed and volatilized, making it impractical.

However, by lowering the material temperature during extrusion as much as possible, we can expect to improve the survival rate to some extent, but in order to do so, it is necessary to suppress heat generation in the extruder, so we have no choice but to reduce the screw rotation speed. As a result, the extrusion speed decreases and the extrusion time increases, which inevitably increases the extrusion cost. On the other hand, PVC doped with infenphos
Most of the compound remained, which shows that it is an extremely effective termiticide.

Infenphos does not cause blooming from the sheath surface even after molding.

Example 2 (field test) PVC (average degree of polymerization P = 1100) 1
00 stabilizer
3 Termiticide isofenphos 0.
5 (unit: parts by weight) A composition in which PVC, stabilizer, and termiticide in the above proportions were mixed with stabilizers II&lL1 to 20 shown in Table 6 below, and a composition without the stabilizer were subjected to a termite feeding damage experiment. The following results were obtained.

In the medium feeding damage experiment, 0.5% of the above PVC composition was applied to the sapwood of a 3an square x 15an long pine tree (no anti-termite treatment).
A sheet obtained by pressing to a thickness of mm was covered, and the overlapping portions and edges were sealed with metal tape, which was buried in the soil of a termite habitat and left for two years.

Of course, PvC sheets without the addition of the termiticide isofenphos, but even those with 0.5 parts added, all those with magnetic 1-6.8 and 15-20 stabilizers suffered no feeding damage. , stabilizer N17,9°10.11,12.1
The PVC sheets to which Nos. 3 and 14 were added did not suffer from feeding damage.

Example 3 (field test) Next, in order to evaluate the synergistic effect of the stabilizer and termiticide, the seventh
A feeding damage experiment was conducted using the formulations shown in the table.

Evaluation was performed after 1 year.

As is clear from the results shown in Table 7, a synergistic effect of the termiticide isofenphos and the stabilizer containing Ba, Cd, or PB on termitproofing properties is observed.

〔Effect of the invention〕

The present invention provides an anti-termite vinyl chloride resin composition that can maintain strong anti-termite properties for a long period of time.
It can prevent damage to buildings, floorboards, pipes, tubes, tapes, cables, etc. for a long time.

Claims (1)

[Claims] (1) Termite-proof vinyl chloride resin composition containing isopropyl-2-[ethoxy(isopropylamino)thiophosphoryloxy]benzoate