JPH03128954A - Flame-retarding composition - Google Patents

Abstract

PURPOSE:To provide a flame-retarding composition excellent in flame retardancy, extruding workability, etc., freed from a problem of forming mildews or the like and desirable as a sheathing material or for CTV cables, etc., by mixing a polyvinyl chloride resin with a zinc compound, a lead stabilizer, an epoxy oligomer and a flame retardant. CONSTITUTION:A flame-retarding composition is produced by mixing a polyvinyl chloride resin (A) with a zinc compound (B) (e.g. zinc borate), a lead stabilizer (C) (e.g. dibasic lead stearate), an epoxy oligomer (D) (e.g. bisphenol A glycidyl ether oligomer) and a flame retardant (E) (e.g. aluminum hydroxide) as the essential components. The mixing ratio among the respective components is suitably such that 3-30 pts.wt. component B, 3-20 pts.wt. component C, 0.5-10 pts.wt. component D and 20-100 pts.wt. component E are used per 100 pts.wt. component A, and a heat stabilizer, an acid acceptor, etc., may be added to the composition.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to flame retardant compositions, more specifically polyvinyl chloride (
This invention relates to a flame-retardant composite material (hereinafter referred to as pvc).

[Conventional technology]

It has been used as a sheath material for electric cables with PVC composite bottoms for a long time, and it has also been common practice to make PVC sheath materials flame retardant in order to maintain electrical properties, such as in high-voltage CVT cables. There is.

In order to make this sheath material flame retardant, it is necessary not only to make the sheath material itself difficult to burn, but also to make the so-called molten drip that flows down when the sheath melts even when it comes into contact with flames small, and to have excellent carbonization ability. required to be present.

To achieve this objective, zinc-based compounds such as zinc borate and zinc oxide (ZnO) have conventionally been incorporated. However, if this zinc-based compound is blended, especially if it is blended to a sufficient extent to prevent melt dripping and form carbonization, it will promote the pvcO de-C1 reaction at the temperature during cable manufacturing, particularly during extrusion, and the pvc will harden. A so-called zinc burning phenomenon occurs, which not only deteriorates the appearance but also, in severe cases, causes holes, etc., which greatly impedes the bottom shape of the product after long-term extrusion.

[Problem to be solved by the invention]

The problem to be solved by the present invention is to solve the above-mentioned problems of the conventional technology. P suitable as a flammable sheath material
It is to develop the composition of the VC group precepts.

[Means to solve the problem]

This problem is solved by the particular choice of epoxy oligomers as fillers in the PVC compositions for the sheaths of CVT cables of this type and their use in combination with zinc compounds.

[Function and structure of the invention]

In the present invention, by blending a zinc compound into this type of PVC composition, it not only imparts flame retardancy, but also prevents melting and formation of charring by preventing flame retardation. improve. By further blending an epoxy oligomer with this, it is possible to overcome the problems caused by blending a zinc compound, that is, the occurrence of burns and holes during extrusion molding, and the difficulty of forming a bottom shape by extrusion for a long time.

According to the research conducted by the present inventor, there is a problem in that mold grows when an epoxy compound such as epoxidized soybean oil is used as an epoxy compound, but such a problem occurs when an epoxy oligomer is used. It has been found that the intended purpose can be achieved without the generation of mold, in other words, it is necessary to select and use epoxy oligomers among epoxy compounds.

Preferred examples of the zinc compound used in the present invention include zinc borate, Mo compound of boric acid, ZnO, etc., and as the lead-based stabilizer, any ordinary PVC stabilizer can be used. .

The epoxy oligomer used in the present invention refers to an epoxy resin as a resin component that is a precursor of a cured epoxy resin and an epoxy resin as a resin component of its curing agent. As the epoxy resin, for example, glycidyl ether type, glycidyl ester type, glycidyl amine type, aliphatic epoxide type, alicyclic epoxide type, etc. can be used. More specifically, glycidyl ether types include bisphenol A glycidyl ether, bisphenol F glycidyl ether, brominated bisphenol A glycidyl ethyl, novolac glycidyl ether, etc., and glycidyl ester types include hexahydrophthalic acid glycidyl ester, dimer acid glycidyl ester, etc. etc., triglycidyl isocyanurate, tetraglycidyl diaminophenylmethane, etc. as glycidylamine type, epoxidized polybutadiene as aliphatic epoxide type, and 3,4 epoxy-6-methylcyclohexylmethyl as alicyclic epoxy type. Examples include carboxylate, 34 epoxycyclohexylmethyl carboxylate, and the like. However, in the present invention, among the aliphatic epoxide types, epoxidized soybean oil is not used for the above-mentioned reason.

As a flame retardant, any of the usual oxidants used in pvcMi can be used, such as aluminum hydroxide,
Examples include magnesium hydroxide, halogen flame retardants containing bromine and chlorine, and antimony flame retardants such as 5b20:+.

The composition of the present invention also contains hydrotalcite to improve thermal stability. z(OR)
Not only can so-called acid acceptors such as +3CO, .3.5H20) and MgO be used together, but other usual additives may be added as necessary. Other common additives include calcium carbonate, silica, clay,
Fillers such as talc, colorants such as carbon blank, EV
A, NBR, (1,-polymer plasticizer compatible with polyvinyl chloride such as PE, powdered polyethylene,
Examples include processing aids such as stearic acid and powdered methylmethacrylate.

In the composition of the present invention, the blending ratio of each component is PVC1
00 parts by weight, 3 to 30 parts by weight of zinc compound, 3 to 20 parts by weight of lead stabilizer, 0.5 to 10 parts by weight of epoxy oligomer.
The flame retardant is preferably 20 to 100 parts by weight. At this time, if the zinc compound does not reach 3 parts by weight, the effect of drip resistance will be low, and if it exceeds 30 parts by weight, the physical properties will deteriorate, and in particular, the amount of water absorption will increase. Also, epoxy oligomer is 0.
If it is less than 5 parts by weight, the effect of improving heat resistance is low, and if it exceeds 10 parts by weight, there is a risk of bleeding. If the flame retardant is less than 20 parts by weight, the flame retardancy will be low, and if it exceeds 100 parts by weight, the physical properties will deteriorate and the amount of water absorbed will increase.

〔Example〕

Examples and comparative examples are given below to make the features of the present invention more clear.

Examples 1 to 7 Various compositions were obtained by blending the prescribed components shown in Table 1 below. However, the blending ratios in the table indicate parts by weight.

Comparative Examples 1 to 4 Various compositions were obtained by blending the prescribed components shown in Table 1 below.

The physical properties of the various compositions obtained in Examples 1 to 7 and Comparative Examples 1 to 4 were measured. The results are also listed in Table 1.

However, the measurement methods for each component and physical properties in Table 1 are as follows.

Ingredients Diacizer D-11: Mixed group alkyl phthalate, Trimex NO, 8: ) Sn-octyl trimellitate, TCP:) Recresyl phosphate, DOS Nidioctyl sebacate, Alkanesox FRC500: Surface treatment zinc borate, Hijirai) H42M: Almonium hydroxide, Epoxidizer W100: Epoxidized soybean oil,
Hydrotalcite DHT-4^: Mga, sA
1! (Off) + 5cOi・3.5H20 (basic magnesium aluminum hydroxy carbonate hydrate), Satent No. 1: Clay league foot friend feces flame retardant 6.6kV 3 x 60sq CVT cable was made and sheathed. Only the formulations of each example and comparative example are covered.

Flame retardancy was evaluated in accordance with the group cable flame retardancy test method of IEEE383-1974. A cable where the fire did not spread to the top was marked as ○, a cable where the fire spread was marked as ×, and a cable where the fire partially spread was marked as Δ.

Thermal stability: 200℃, 6.
Changes in torque over time for each sheath composition were measured under the conditions of 0 g and 80 rpm rotor rotation. Thermal stability was evaluated based on the length of time it takes for torque to suddenly rise.

Under the above conditions, 90 minutes or more was marked as ○, and 60 minutes or less was marked as ×.

Mold Resistance Test In a test conducted in accordance with JIS Z 2911-1981, a compound composition with a mold growth area of less than 10% was rated as ○, and a composition with a mold growth area of less than 10% was rated as x.

Water Absorption A sample of each composition having a thickness of 1 mm, a width of 25 nm, and a length of 60 mm was immersed in warm water at 70°C for 5 days, and the water absorption (% by weight) was determined from the weight change before and after immersion. Water absorption is 2.5
The case where it was less than % was rated as ○, and the case where it was 2.5% or more was rated as ×.

Extrusion workability Using a PVC extruder with a diameter of 90 mm, for each compounding composition, die = 180°C, cylinder 3: 170°C,
It was extruded into a tube shape under the following conditions: cylinder 2: 170°C, cylinder 1: 160°C, screw rotation speed: 25 rpm. In extrusion into a tube shape, those with no change in appearance for 2 hours or more were rated ○, and those with rough appearance after less than 2 hours were rated x.

〔effect〕

As is clear from Table 1, the composition of the present invention has excellent flame retardancy, good extrusion workability, and does not generate mold, making it an extremely excellent material for the sheath of CTV cables. It is.

Claims (2)

[Claims] (1) A flame-retardant composition comprising polyvinyl chloride, a zinc compound, a lead-based stabilizer, an epoxy oligomer, and a flame retardant. (2) 100 parts by weight of polyvinyl chloride, 3 to 3 parts of zinc compound
A composition according to claim 1, comprising: 0 parts by weight, 3 to 20 parts by weight of a lead-based stabilizer, 0.5 to 10 parts by weight of an epoxy oligomer and 20 to 100 parts by weight of a flame retardant.