Reduced-inflammability pvc cable plasticate

FIELD: electrical engineering; polymeric compositions based on reduced-inflammability plasticized polyvinyl chloride.

SUBSTANCE: proposed suspended polyvinyl chloride based polymeric composition designed for insulating internal and external sheaths of wires and cables has following ingredients, mass percent: suspended polyvinyl chloride, 100; ester plasticizer, 45-70; chlorinated wax and/or chlorinated alpha-olefins, 15-20; tribasic lead sulfate, 5-7; calcium stearate, 1-2; aluminum hydroxide or magnesium hydroxide, 45-60; antimony trioxide, 5-10; diphenyl propane, 0.1-0.5; 4.4'-isopropylidenediphenol epoxy resin, 23-4; carbon black, 0.5-2.0.

EFFECT: reduced inflammability, enhanced volume resistivity, thermal stability, and melt fluidity of composition.

2 cl, 1 tbl, 11 ex

 

The invention relates to a cable technique, namely to polymeric compositions based on plasticized polyvinyl chloride (PVC) with reduced Flammability, smoke and hydrogen chloride during combustion, designed to isolate the inner and outer layers of wires and cables, operating in conditions of high fire risk.

Wires and cables are often the cause of the fire and flame spread. So to cable compounds are always high requirements.

There are a large number of publications in reducing fire hazard in various combinations based on PVC. Part of PVC compound with low Flammability, as a rule, fire retardants to reduce Flammability, dumpdevice, scavengers of hydrogen chloride to reduce the allocation corrosive volatile combustion products, plasticizers, fillers, stabilizers.

Known polymer composition on the basis of suspension polyvinyl chloride, characterized by lower Flammability, low smoke and hydrogen chloride during combustion, containing parts by weight of:

Suspension PVC100
Ester plasticizer40-80
Lead stabilizer is PR 3-7
Calcium carbonate30-500
The trihydrate of alumina10-100
Antimony trioxide4-7,5
Boric acid0,4-0,6
BHT0,1-0,6
The diphenylolpropane0,1-0,6

(patent RF №2195729, CL L 27/06, 2002).

The disadvantages of this composition are low technological properties, namely the fluidity of the melt and thermal stability.

The closest set of features to the proposed technical solution is flame-retardant polymer composition on the basis of suspension polyvinyl chloride containing parts by weight of:

Suspension PVC100
Ester plasticizer45-52
Lead stabilizer4-6
The hydrate of aluminum oxide10-30
Antimony trioxide4-9
Aerosil3-5
Epoxy Dianova resin2-4

(patent RF №2034874, 08L 27/06, 1995).

The disadvantages of this composition are poor indicators of thermal stability and melt fluidity, lack of fire is th and increased adhesiveness of their granules.

The processing composition in modern high-speed extruders creates in the melt polymer significant shear forces, to reduce which should increase the melt flow of the polymer to prevent overheating it in extruders.

The objective of the invention is to provide polymeric compositions with low Flammability based on suspension of polyvinyl chloride with a high specific volume resistance, high technological properties, thermal stability, fluidity of the melt, decreased adhesiveness of their granules, pore agglomerates of filler.

The problem is solved in that the polymer composition is reduced combustibility comprising suspension PVC, dioctylphthalate, dioctylsebacate, rejonowy sulphate of lead, antimony trioxide, flame retardant epoxy Dianova resin further comprises a secondary plasticizer is a chlorinated paraffin and/or chlorinated α-olefins, calcium stearate, diphenylolpropane, soot, and as a flame retardant - fine aluminum hydroxide or magnesium hydroxide with an average particle size of not more than 5 μm, in the following ratio of components, parts by weight:

Suspension PVC100
Ester plasticizer45-70
Chlorinated paraffin and/or
chlorinated α-olefins15-20
Rejonowy lead sulfates5-7
Calcium stearate1-2
The aluminum hydroxide or magnesium hydroxide45-60
Antimony trioxide5-10
The diphenylolpropane0,1-0,5
Epoxy Dianova resin2-4
Soot0,5-2,0

Chlorinated alpha-olefins produced by chlorination of waste produced by oligomerization of ethylene alpha-olefin fraction With14-C32in the presence of initiator dicetylperoxydicarbonate (solidox), taken in an amount of 0.1-0.3 wt.% by weight of alpha-olefins at a temperature of 35-70°and a feed rate of chlorine 0.1-0.3 g/min to the degree of chlorination 24-53,7 wt.%.

In the inventive polymer compositions used finely dispersed hydrate of aluminum oxide (TU 6-47-107-88) or magnesium hydroxide (magnesium hydroxide 95%) average particle size of not more than 5 μm - country of origin: European community.

As the ester plasticizer composition using dioctylphthalate (DOP), diallylphthalate (DAP), dioctyl bazinet (DOC) according to GOST 8728-88 or a mixture of the above plasticizers.

Use in the formulation of non-combustible cable compound fine aluminum hydroxide or magnesium hydroxide, antimony trioxide, chlorinated paraffin wax CP-470 and/or chlorinated α-olefins, obtained from waste products of the oligomerization of ethylene in combination with stabilizers: trehosnovnoy the lead sulfate, calcium stearate, epoxy Dianova resin, diphenylolpropane, imparts increased resistance, thermal stability, fluidity of the melt, provides pores and agglomerates, prevents sticking of the granules, creates a glossy surface.

In addition, it becomes possible to reduce the composition through the use of secondary plasticizers-chlorinated paraffin wax CP-470, chlorinated alpha-olefins derived from waste oligomerization of ethylene.

The invention is illustrated by the following examples.

Example 1. In a mixer heated to 90°download all loose components, parts by weight: suspension PVC 100, rejonowy sulphate of lead 6, calcium stearate and 1.5, aluminum hydroxide, 49,5, antimony trioxide 9,5, diphenylolpropane 0,4, soot 1, stirred for 3-5 min, administered DOP 20, DOS 30,5, CP-470 20, epoxy Dianova resin 3, stirred for another 25 minutes the Obtained powder mixture is cooled to room temperature and roll at a temperature of 155-165°SV for 4-10 minutes

Flammability KI is determined according to GOST 21793, volume resistivity at 20°determined according to GOST 64332, the embrittlement temperature is determined according to GOST 16783, the fluidity of the melt is determined according to GOST 11645-73.

The composition and properties of the composition given in the table.

Examples 2-11 composition prepare and test as in example 1.

We offer a polyvinylchloride composition has a relatively low Flammability, high technological properties: stability, fluidity of the melt, also has frost, no sticking together of the granules, then and agglomerates, creates a glossy finish.

1. Polymer composition with low Flammability, including suspension polyvinyl chloride, ester plasticizer, rejonowy sulphate of lead, antimony trioxide, flame retardant epoxy Dianova resin, characterized in that the composition further comprises a secondary plasticizer - chloroparaffin CP-470 and/or chlorinated α-olefins, calcium stearate, diphenylolpropane, carbon black, aluminum hydroxide or magnesium hydroxide with an average particle size of not more than 5 μm in the following ratio of components, parts by weight:

Suspension PVC100
Slojnoe the RNA plasticizer 45-70
Chlorinated paraffin and/or
chlorinated α-olefins15-20
Rejonowy lead sulfates5-7
Calcium stearate1-2
The aluminum hydroxide or magnesium hydroxide45-60
Antimony trioxide5-10
The diphenylolpropane0,1-0,5
Epoxy Dianova resin2-4
Soot0,5-2,0

2. Polymer composition according to claim 1, characterized in that the chlorinated α-olefins is produced by chlorination of waste produced by oligomerization of ethylene alpha-olefin fraction With14-C32in the presence of initiator dicetylperoxydicarbonate (solidox), taken in an amount of 0.1-0.3 wt.% from mass α-olefins at a temperature of 35-70°and a feed rate of chlorine 0.1-0.3 g/min to the degree of chlorination 24-53,7 wt.%.



 

Same patents:

FIELD: insulation materials.

SUBSTANCE: invention relates to polyethylene composition for insulation of conductors and cables, which exhibits improved scorching resistance and consists of (i) polyethylene and scorching inhibitor having melting point under atmospheric pressure below 50°C and being compound depicted by general formula I, wherein R1 represents optionally phenyl-substituted С120-alkyl, С220-alkenyl, С320-alkynyl, С39-cycloalkyl, phenyl, or tolyl; R2 and R3, independently from each other, represent С120-alkyl optionally substituted by following substituents: phenyl, one or two hydroxyls, cyano group, formyl, acetyl, and -O-COR5; R5 represents С120-alkyl, С220-alkenyl, С320-alkynyl, or optionally hydroxyl-substituted С39-cycloalkyl; phenyl, 4-chlorophenyl, 2-methoxycarbonylphenyl, p-tolyl, 1,3-benzothiazol-2-yl, -(CHR6)nCOOR7, or -(CHR6)nCONR8R9, wherein n=1 or 2, R6 represents hydrogen atom or С16-alkyl; R7 С120-alkyl optionally interrupted with 1-5 O or S atoms, С57-cycloalkyl, phenyl, benzyl, or tolyl; R8 and R9 each represents hydrogen atom or С16-alkyl; R4 represents hydrogen atom or methyl; and (ii) organic peroxide. Composition may be extruded with minimum preliminary cross-linking, even at sufficient cross-linking rate. Polyethylene composition for insulation of conductors and cables with improved scorching resistance is described, which composition additionally contains an amine selected from group consisting of diphenylamine, 4-tert-butyldiphenylamine, 4-tert-octyldiphenylamine, 4,4'-di-tert-butyldiphenylamine, 2,4,4'-tris-tert-butyldiphenylamine, 4-tert-butyl-4'-tert-octyldiphenylamine, o,o', m,m'- or p,p'-di-tert-octyldiphenylamine, 2,4-di-tert-butyl-4'-tert-octyldiphenylamine, 4.4'-di-tert-octyldiphenylamine, 2,4-di-tert-octyl-4'-tert-butyldiphenylamine. This composition may be extruded with minimum preliminary cross-linking, even at sufficient cross-linking rate. Method for preparing cross-linked polyethylene composition is also disclosed. (I).

EFFECT: enhanced resistance against preliminary vulcanization at simultaneously preserved satisfactory vulcanization rate and density of cross linkages formed.

3 cl, 5 tbl

FIELD: electrical communication components; cables whose conductors are covered with polymeric insulation extruded about conductor.

SUBSTANCE: proposed cable has its conductors covered with insulation that has at least one component incorporating maximum 20, and best of all 15, mass percent of polymer characterized in high degree of extrudate swelling. This polymer is defined as that characterized in extrudate swelling degree over 55% and higher, best of all that having extrudate swelling degree over 65%. Best insulation has at least second component of high degree of cracking resistance under stress; therefore, minimal combination of these polymers will provide for insulation layer possessing unique combination of physical properties, including high degree of foaming, fine uniform cellular structure, reduced attenuation, and cracking resistance under stress which is capable of sustaining temperature of 100 °C over 100 h without cracking in spirally coiled state at stress level one-fold higher than outer diameter of insulation.

EFFECT: improved electrical characteristics and mechanical strength of insulation.

23 cl, 6 dwg, 3 tbl

FIELD: cable industry.

SUBSTANCE: proposed composition designed for insulating sheaths of cables and wires operating under high fire hazard conditions has following proportion of ingredients, part by mass: suspension polyvinyl chloride, 100; ester plasticizer, 35 - 65; lead stabilizer, 2 - 7; calcium carbonate, 5 - 45; aluminum oxide trihydrate, 20 - 100; antimony trioxide, 5 - 9; zinc oxide, 0.5 - 8; and newly introduced zinc borate, 0.5 - 8; calcium stearate, 1 - 3; calcium chloride, 0.1 - 2 or calcium oxide, 0.1 - 2.

EFFECT: enhanced fire resistance at low degree of smoke emission under fire conditions.

1 cl, 1 tbl

FIELD: cable industry.

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EFFECT: reduced inflammability and smoke-forming capacity due to introduction of zinc oxide, zinc borate, and calcium chloride or calcium oxide.

3 cl, 1 tbl

FIELD: electrical engineering.

SUBSTANCE: proposed polymeric insulating composition given in description of invention together with description of cables and wires covered with such composition to ensure their excellent performance in service has 60 to 90 mass percent of copolymer A of ethylene and α-olefin produced by copolymerization with aid of concentric catalyst and 40 to 10 mass percent of polyolefin resin B other than copolymer A and includes polyolefin incorporating grafted substituents with dipole moment 4 D or higher. One of alternative compositions uses semiconducting composition as semiconductor layer. In particular cases ethylene and α-olefin copolymer is produced by polymerization with aid of Ziegler-Natta catalyst.

EFFECT: facilitated production.

8 cl, 2 tbl

FIELD: cable industry.

SUBSTANCE: proposed composition designed for insulating and sheathing cables and wires meant for operation under high fire hazard conditions incorporates following ingredients, parts by weight: suspension polyvinyl chloride, 100; ester plasticizer, 30 - 70; tribasic lead sulfate, 2 - 6; calcium carbonate, 20 - 300; zinc oxide, 0.5 - 10; aluminum oxide trihydrate, 20 - 70; antimony trioxide, 3 - 8; zinc borate, 0.5 - 8; zinc stearate, 0.25 - 4. Zinc borate and stearate introduced in definite proportion into proposed composition have made it possible to improve fire-safety characteristics of the latter.

EFFECT: reduced emission of smoke and hydrogen chloride in burning, enhanced degree of inflammability.

1 cl, 1 tbl

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8 cl, 1 tbl, 1 ex

The invention relates to the field of electrical engineering, in particular to electrical insulating compositions for the manufacture of insulation Marco different cables, including insulation of heat-resistant wires and cables, and insulation of wires and cables for use in corrosive environments

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The invention relates to insulation for electric wires or cables

FIELD: insulating materials for telecommunication cables.

SUBSTANCE: polyolefin insulation of conductors in hydrocarbon lubricant filled telecommunication cable which is then placed in junction box operating in the open is susceptible in particular to adverse impact of heat, oxygen, and moisture. In order to ensure reliable functioning of these conductors under mentioned conditions, use can be made of combination of one or more primary phenolic antioxidants chosen from N,N'-hexane-1.6-diilbis-(3(3.5-di-tertiary-butyl-4-hydroxyphenylpropionamide)), tris(3.5-di-tertiary-butyl-4-hydroxybenzyl)isocyanin-rhata, and tris(2-(3.5-di-tertiary-butyl-4-hydroxyhydrocinnamoyloxy)-ethyl)isocyanourate together wit one or more alkyl hydroxyphenyl alkanoylhydrazine metal deactivators.

EFFECT: enhanced oxidation resistance of polyolefin insulation of conductors.

8 cl, 1 tbl, 1 ex

FIELD: cable industry.

SUBSTANCE: proposed composition designed for insulating and sheathing cables and wires meant for operation under high fire hazard conditions incorporates following ingredients, parts by weight: suspension polyvinyl chloride, 100; ester plasticizer, 30 - 70; tribasic lead sulfate, 2 - 6; calcium carbonate, 20 - 300; zinc oxide, 0.5 - 10; aluminum oxide trihydrate, 20 - 70; antimony trioxide, 3 - 8; zinc borate, 0.5 - 8; zinc stearate, 0.25 - 4. Zinc borate and stearate introduced in definite proportion into proposed composition have made it possible to improve fire-safety characteristics of the latter.

EFFECT: reduced emission of smoke and hydrogen chloride in burning, enhanced degree of inflammability.

1 cl, 1 tbl

FIELD: electrical engineering.

SUBSTANCE: proposed polymeric insulating composition given in description of invention together with description of cables and wires covered with such composition to ensure their excellent performance in service has 60 to 90 mass percent of copolymer A of ethylene and α-olefin produced by copolymerization with aid of concentric catalyst and 40 to 10 mass percent of polyolefin resin B other than copolymer A and includes polyolefin incorporating grafted substituents with dipole moment 4 D or higher. One of alternative compositions uses semiconducting composition as semiconductor layer. In particular cases ethylene and α-olefin copolymer is produced by polymerization with aid of Ziegler-Natta catalyst.

EFFECT: facilitated production.

8 cl, 2 tbl

FIELD: cable industry.

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3 cl, 1 tbl

FIELD: cable industry.

SUBSTANCE: proposed composition designed for insulating sheaths of cables and wires operating under high fire hazard conditions has following proportion of ingredients, part by mass: suspension polyvinyl chloride, 100; ester plasticizer, 35 - 65; lead stabilizer, 2 - 7; calcium carbonate, 5 - 45; aluminum oxide trihydrate, 20 - 100; antimony trioxide, 5 - 9; zinc oxide, 0.5 - 8; and newly introduced zinc borate, 0.5 - 8; calcium stearate, 1 - 3; calcium chloride, 0.1 - 2 or calcium oxide, 0.1 - 2.

EFFECT: enhanced fire resistance at low degree of smoke emission under fire conditions.

1 cl, 1 tbl

FIELD: electrical communication components; cables whose conductors are covered with polymeric insulation extruded about conductor.

SUBSTANCE: proposed cable has its conductors covered with insulation that has at least one component incorporating maximum 20, and best of all 15, mass percent of polymer characterized in high degree of extrudate swelling. This polymer is defined as that characterized in extrudate swelling degree over 55% and higher, best of all that having extrudate swelling degree over 65%. Best insulation has at least second component of high degree of cracking resistance under stress; therefore, minimal combination of these polymers will provide for insulation layer possessing unique combination of physical properties, including high degree of foaming, fine uniform cellular structure, reduced attenuation, and cracking resistance under stress which is capable of sustaining temperature of 100 °C over 100 h without cracking in spirally coiled state at stress level one-fold higher than outer diameter of insulation.

EFFECT: improved electrical characteristics and mechanical strength of insulation.

23 cl, 6 dwg, 3 tbl

FIELD: insulation materials.

SUBSTANCE: invention relates to polyethylene composition for insulation of conductors and cables, which exhibits improved scorching resistance and consists of (i) polyethylene and scorching inhibitor having melting point under atmospheric pressure below 50°C and being compound depicted by general formula I, wherein R1 represents optionally phenyl-substituted С120-alkyl, С220-alkenyl, С320-alkynyl, С39-cycloalkyl, phenyl, or tolyl; R2 and R3, independently from each other, represent С120-alkyl optionally substituted by following substituents: phenyl, one or two hydroxyls, cyano group, formyl, acetyl, and -O-COR5; R5 represents С120-alkyl, С220-alkenyl, С320-alkynyl, or optionally hydroxyl-substituted С39-cycloalkyl; phenyl, 4-chlorophenyl, 2-methoxycarbonylphenyl, p-tolyl, 1,3-benzothiazol-2-yl, -(CHR6)nCOOR7, or -(CHR6)nCONR8R9, wherein n=1 or 2, R6 represents hydrogen atom or С16-alkyl; R7 С120-alkyl optionally interrupted with 1-5 O or S atoms, С57-cycloalkyl, phenyl, benzyl, or tolyl; R8 and R9 each represents hydrogen atom or С16-alkyl; R4 represents hydrogen atom or methyl; and (ii) organic peroxide. Composition may be extruded with minimum preliminary cross-linking, even at sufficient cross-linking rate. Polyethylene composition for insulation of conductors and cables with improved scorching resistance is described, which composition additionally contains an amine selected from group consisting of diphenylamine, 4-tert-butyldiphenylamine, 4-tert-octyldiphenylamine, 4,4'-di-tert-butyldiphenylamine, 2,4,4'-tris-tert-butyldiphenylamine, 4-tert-butyl-4'-tert-octyldiphenylamine, o,o', m,m'- or p,p'-di-tert-octyldiphenylamine, 2,4-di-tert-butyl-4'-tert-octyldiphenylamine, 4.4'-di-tert-octyldiphenylamine, 2,4-di-tert-octyl-4'-tert-butyldiphenylamine. This composition may be extruded with minimum preliminary cross-linking, even at sufficient cross-linking rate. Method for preparing cross-linked polyethylene composition is also disclosed. (I).

EFFECT: enhanced resistance against preliminary vulcanization at simultaneously preserved satisfactory vulcanization rate and density of cross linkages formed.

3 cl, 5 tbl

FIELD: electrical engineering; polymeric compositions based on reduced-inflammability plasticized polyvinyl chloride.

SUBSTANCE: proposed suspended polyvinyl chloride based polymeric composition designed for insulating internal and external sheaths of wires and cables has following ingredients, mass percent: suspended polyvinyl chloride, 100; ester plasticizer, 45-70; chlorinated wax and/or chlorinated alpha-olefins, 15-20; tribasic lead sulfate, 5-7; calcium stearate, 1-2; aluminum hydroxide or magnesium hydroxide, 45-60; antimony trioxide, 5-10; diphenyl propane, 0.1-0.5; 4.4'-isopropylidenediphenol epoxy resin, 23-4; carbon black, 0.5-2.0.

EFFECT: reduced inflammability, enhanced volume resistivity, thermal stability, and melt fluidity of composition.

2 cl, 1 tbl, 11 ex

FIELD: cable engineering.

SUBSTANCE: proposed smoke-emitting plasticized PVC based polymeric composition used for manufacturing insulation and cable sheaths has following ingredients, mass by part: suspension polyvinyl chloride, 100; ester plasticizer, 40-90; lead stabilizer, 2-8; antimony trioxide, 2-10; zinc oxide, 2-4; boron acid, 2-5; ocher, 10-70; calcium stearate, 1-3; diphenylolpropane, 0.1-0.4.

EFFECT: enhanced heat resistance of composition, its compliance with requirements to smoking under conditions of burning, smoldering, and hydrogen chloride emission in burning.

1 cl, 2 tbl

FIELD: chemistry; insulation.

SUBSTANCE: invention pertains to a cable with a coating layer, made from waste materials. The cable consists of at least, one conductor with at least one transfer element and at least one layer of coating. The coating material contains between 30 mass % and 90 mass % of the overal mass of the coating material, at least, first polyethylene with density not more than 0.940 g/cm3 and melt flow index from 0.05 g/10 min. to 2 g/10 min., measured at 190°C and a load of 2.16 kg in accordance with standard ASTM D1238-00, and quantity from 10 mass % to 70 mass % of the overall mass of the coating material, at least, second polyethylene with density of more than 0.940 g/cm3. The first polyethylene is obtained from waste material. Use of at least, one polyethylene with density of more than 0.940 g/cm3 in the recycled polyethylene allows for obtaining a layer of coating, capable of providing for mechanical characteristics, in particular, breaking stress and tensile strength, comparable to characteristics of primordial polyethylene. The stated coating layer is preferably used as an external protective coating.

EFFECT: obtaining of a new type of cable insulation.

43 cl, 9 dwg, 4 tbl, 10 ex

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