SU1030386A1 - Self-extinguishing magnetic polymeric composition - Google Patents

Abstract

MAGNETIC SELF-DUMPING POLYMER COMPOSITION, including polyolefin, magnetic filler and flame retardant, characterized in that, with a view to improving the magnetic properties, as well as fire and heat resistance, it contains as a magnetic filler barium or strontium ferrite and as a flame retardant, as a magnetic flame retardant. the following ratio of components, wt.%: Ferrite barium or -. . Strontium 70-80 Decabromdiphenyl Oxide .5-12 Polyolefin Remaining g

Description

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The invention relates to polyolefin compositions, namely, self-damping, magnetizable compositions, used in the electronics industry for the manufacture of permanent magnets, in particular, centering magnets of televisions (ITC), a well-known composition intended. for the manufacture of permanent magnesium, including polyethylene and ferrite, barium fl. The composition has strong magnetic properties, but it burns and has low heat resistance. Also known is a composition containing polypropylene and barium ferrite 2. The composition intended for the manufacture of ITC has satisfactory magnetic properties and heat resistance, but it burns. The closest set of features and the effect achieved is a self-sintering composition containing a homo- or copolymer of olefin, barium ferrite and, as a pyrene, is - (2.4, b-tri-bromophenyl 2,3,5, 6-tetrachloro terephthalate { f-4b) 3 However, this composition is not satisfactory in terms of the magnetic properties, fire and heat resistance of modern tepevrani ji ,. presented to the centering magnets of the night TVs. - The aim of the invention is to increase the magnetic properties, as well as the fire and heat resistance of the magnetic sate of the composition. This goal is achieved by the fact that a magnetic polyolefin-based composite composition, including aa magnetic filler and a flame retardant, contains ferrite barium or strontium as the magnetic filler, and decabromobiphenyl oxide as the flame retardant, in the following ratio, wt.%: Barite ferrite or strontium 70 -80 Decabromodiphenyl Oxide (DBD) Sria Polyolefin Remaining As a polyolefin, the composition contains high density polyethylene (HDPE) or polypropylene (PP), and the magnetic filler is barium ferrite (BaO-eFe o) silt ferrite strab 1z (SrO6Fe2 (with a specific surface area of 0.5-2.0. The flame retardant content limits are set proportionally to the concentration of the polyolefin and magnetic filler in the composition: with a maximum of polyolefin and a minimum of magnetic filler of 12 wt.%, and with a minimum of polymer and maximum of magnetic filler - 5% by weight. If necessary, the composition may contain targeted additives, such as glidants, heat stabilizers, etc. Examples 1-8. The compositions are prepared in a Banbury type mixer by introducing into the polyolefin melt successively barium ferrite or ferrita and strontium, flame retardant and other additives c. followed by stirring at 1 ° -190 ° C for 25-40 minutes, depending on the type of polyolefin and the amount of additives. The resulting composition is rolled, and then by direct pressing, plates are obtained at 170–200 ° C and a specific pressure of 30–40 kgf / cm. Test plates are cut from the plates. Examples 9 and 10- (control) .. Compositions are prepared in a Banbury type by introducing a flame retardant into the melt of polyolefin with stirring at 170-180 ° C for 10-12 minutes. In tab. 1 shows the formulations of the compositions. The results of testing samples made according to examples i 2-10, are presented in table. 2. The Vicat softening temperature (heat resistance) is determined with a load of 5 ug according to GOST 15065-69. Flammability (fire resistance) - according to the PGA (IL-94) method, instructions 20154003 (CllIA). Magnetic properties were determined on an EM8-6 hysteresisograph by the Weiss method. Density was determined by a hydrostatic weighting method-j nor according to GOST 15130-69.

Table

Polypropylene brand 21060 (TU 6-05-1756-78) High density polyethylene brand 21008-075 (GOST 16338-77) Strontium ferrite (TU 6-094621-79) Barite ferrite (TU-6-09J591-77): Decabromylphenyl oxide ( TU 6-22-43-19) g -,,. U5is- (2,4,6-tibromophenyl) f2, 3,5, b-tetrachloroterephthalate (TU 6-14-22-141-76) Calcium stearate (TU-6-14722-76) S, Y-Dinaftil -P-phenylenediacia (diafen NN) TU 6-141054-76

The fire resistance imparted to pure polyolefin by the introduction of F-46 flame retardant is higher or is at the level of the properties of a non-magnetic composition with DBD flame retardant (example 9k and DOC). However, when replacing the flame retardant 18 16 - 18 - 18 -75 - 70 - 70 7 - - - 1 12 9 12 Ф-46 in the magnetic self-extinguishing composition based on polyolefin on the DVD fire retardant, the density of the composition increases, simultaneously its magnetic properties, fire resistance (tab. 2-).

- Table 2 6- 14,8514,98 85 85 -18 -. 5- - -70 8075 912 510 - 15 - - 15 0, 05 0.02.0, 1 - V

Given in Table. The preset values are that the proposed composition containing DBD has improved; properties of the properties compared to the composition containing the flame retardant

Continued table. 2

V-46. Thus, the magnetic properties and heat resistance of the compositions with DBD as a flame retardant increase by an average of 15%, and the average time of self-burning reduces this by a factor of 2-3.

Claims (1)

MAGNETIC SELF-EXTINGUISHING EXTINGUISHING POLYMER COMPOSITION, comprising a polyolefin, a magnetic filler and a flame retardant, characterized in that, in order to increase magnetic properties, as well as fire and heat resistance, it contains barium or strontium ferrite as a magnetic filler and decabromide as flame retardant in the following ratio, wt.%: Barium or strontium ferrite Decabromd diphenyl oxide Polyolefin 70-80 5-12 The rest of the fo oo o 10303B6