DE2131845B2 - Curable plastic molding compounds for the production of molded parts with increased arc resistance - Google Patents

Description

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The production of the molding compounds takes place in itself lower than the decomposition temperature of the polymer

known manner, with peroxide compounds used instead of fumaric acid also

Maleic acid can be used, which is the case with the gene

customary production of polyesters at least as copolymerizable unsaturated monomers

Part m fumaric acid rearranged 5 such vinyl and / or allylver-

Molded parts made from molding compounds built up in this way have bonds with a boiling point above 14O ⁰ C,

even under extreme conditions surprisingly preferably about 170 ⁰ C, used for example advertising

wise a very high arc resistance, which is called styrene, m- or p-vinyl-toluene, halogen

Large order in molded parts made from the well-known nated styrene, α-methylstyrene, diallyl maleate, diallyl fumarate,

Masses could not be observed so far you io -itaconate, -succinate, -adipate, -azelate, -sebacate, -phtha-

also have a high tracking resistance and lat-, -isophthalate, triallyl cyanurate, triallyl phosphate,

a greatly improved flame resistance.

Molding compounds are therefore for the production of Isola- tetraallylather or Tnmethylolpropane-tallylather,

gates of all kinds, especially for high voltage technology, ethylene glycol dimethacrylate, hexahydro-l ^ .S-triacryl-

and for switch parts or switch linings, 15 otriazm or the like. In general, the proportion is

especially suitable, also for other applications in the monomers between 3 and 50, preferably

in electrical engineering, such as quenching chambers, in the range between 10 and 40%, based on the weight of the

stungselektromk ζ ß. Thyristor parts and all iso-polyester monomer mixtures

parts for high voltages and / or currents As organic peroxides, for example

For the diol component of the unsaturated polyester ao benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert -buke symmetrical diols with 2 equally reactive tylperoxide or hydroperoxide, lauroyl peroxide, cyclo-OH groups, preferably ethylene glycol, in behexanone peroxide, cumene hydroperoxide, tert-butyl peroxide, but also unsymmetrical diols with different acetate, tert-butyl perbenzoate, monotert-butyl-permaden reactive OH groups Mol percent, 25 zoylperoxy) -hexane, 2,5-dimethyl-2,5-di (tert -butyl based on the total applied diol, are peroxy) -hexane, 2,5-dimethyl-2,5-di (tert -butylperoxy ) -The symmetrical diols are preferred if hexyne or the like are used 4%, based on the G all a polyester with a lower degree of plasticity 30 weight of the polyester and the monomer, desired. Further suitable symmetrical diols are det. The decomposition temperature of the peroxide compounds ζ B diethylene glycol, 1,3-propanediol, 1,4-butanediol, is 60 to 8O ⁰ C, butanediol-2,3, Δ-2,3-butenediol-1, depending on the type of catalyst, 4,2,2-Dimethylpro- partly also above 80 and even above 100 ⁰ C by pandiol-1,3, 1,4-dimethylolcyclohexane, 4,4'-Dihy- the process according to the invention is thus because of hydroxydicyclohexylpropane or its homologues or 35 the reduced melting temperature the processing of bisethylene, bispropylene or bisbutylene glycol- tungsicherheit when mixing the ingredients increases ether or such ethers of 4,4'-dihydroxydiphenyl Their alkali or alkaline earth diol is preferably 1,2-propanediol, salts, so-called ester waxes, esters of stearic acid, especially when the symmetrical diol used is ethylene with high molecular weight alcohols, so-called polyglycol , since the composition of the amide waxes, reaction products of high molecular weight mixtures due to the similar molecular weight of polyamines with fatty acids, degraded polyethylenes of propanediol and ethylene glycol would otherwise not grow, which have a molecular weight of not more than 10,000, preferably not more than 5,000, as well

The use of 1,2-propanediol results in 45 silicon compounds.

also the water absorbency and the shrinkage. The red phosphorus, which reduces the deflagration of the moldings. Other suitable flammability is added to the asymmetrical diols according to the invention
1,3-butanediol, 1,4-pentanediol and asymmetrical fillers are inorganic, ground mate-hydroxyl-group-containing ethers of the dihydroxy chain in the form of oxides, sulfates and preferably diphenylpropane or its homologues, 1,3-dimen-wise carbonates, ζ B calcium carbonate, magnethylolcyclohexane or the like siumoxid, calcium sulfate, barium sulfate, but also

The use of polyesters made from certain clays is preferred, and also mixtures

approximately equimolecular amounts of acids and such substances

of the dihydric alcohols The excess of one i 55 As reinforcing substances to increase the mechani-reaction component should not see higher properties, organic, primarily 5 equivalent percent, preferably not higher but inorganic fibers are used, such as glass ais 2 equivalent percent by choosing the two fibers with customary known cut lengths and valued alcohols or by using known adhesion promoters and sizes, asbestos, mixtures of several alcohols, polyester 60 WoUastonit, polyamide, polyethylene terephthalate, polyamide, which to a greater or lesser extent lyacrylnitnl, - or natural fibers, such as cotton contain crystalline structural areas The subsequent perforated disk extrusion after the Lo-Mixing is composed in such a way that the solvent process ⁰ C, pastes that contain all the necessary components of the molding compound

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Keep, to impregnate, to dry if necessary. Arc resistance according to ASTM D 495

and grind into small even pieces <240 seconds

The processing of the molding compositions according to the invention can ζ B after the compression molding, transfer molding The arc resistance 40 kV / 100 mA was after or injection molding processes are carried out or the following method is determined. On one of the forms After the extrusion process for the production of mass-produced plate, two electrodes are in of endless profiles It is carried out under the mounted for a distance of 30 mm at 40 kV Saturated polyester molding compounds in favorable conditions- voltage becomes an electric arc with a strong current gen So ζ B is drawn between the electrodes for a perfect 30 mm thickness of 100 mA, the Plate in the compression process with tabletting and vorio touches the plastic surface and extremely warm in the high-frequency field at most one hard- ly loaded. The time is the arc resistance time of 5 minutes at 140 ° C mold temperature specified in seconds until the short-circuit. You need it carries well over 5 minutes while they are molded parts The molded parts are characterized by increased creep from the best known molding compounds under one current and arc resistance, ζ B is 15 minutes

(a) the tracking resistance according to DIN 53480, tracking resistance according to DIN 53480,

measured according to procedure KA with the test solution measured according to procedure KB with test solution A:

A. Level KA 3c and Level KB> 600,

measured according to KB method with the test solution glow resistance according to DIN 53459: grade 4,

A or F- level KB> 600, ^ao (weight loss 100 mg, flame path 0.5 cm)

(b) the arc resistance according to ASTM-D 495

> 240 seconds comparison test

(c) In addition, the molded part ζ B a. ,, _ "

30 mm long alternating current arc (40 kV, ⁵ ^ "of ^the talk proposed by the invention

100 mA) act for several hours without ² S becoming exclusively 42.5 as an inorganic fuel

A conductive bridge is formed and ground kaohnite is used without any weight

the molding material as a result of high temperature ⁱⁿ S ^le , | ^cher ^ f ^se ' ^WIC , T ^ T f ? ***

increase by melting, decomposing, cracking processed plate has the following properties

etc. Arc resistance according to ASTM D 495 is destroyed

",. "_, R> 1 ³ °> 182 seconds,

Molded parts made from normal unsaturated polyester arc resistance, tested according to the

But also molding compounds made from melamine-formaldehyde _layers | _rufmet ^ _ode ^ _{40 kv and} 100 mA

and epoxy compounds, of course also from c seconds

Phenol-formaldehyde, urea-formaldehyde and Knechstrom resistance according to DIN 53480,

Melamine-phenol-formaldehyde compounds, on the other hand, form 35 Procedure with test solution A: Level KB 480,

if in particular the tests (b) and (c) ember resistance according to DIN 53459. Grade 4

Conductive bridges are commercially available (weight loss 100 mg, flame path 0.5 cm) Borrowed thermoplastics behave in the same way or

melt under the action of the arc. These values show the major disadvantages compared to

The values given under (a) to (c) were 40 moldings made from the compositions according to the invention from the moldings according to the invention
after 300 days of outdoor exposure in industrial air

A further increase in the weather resistance. ₂

This can be achieved through a suitable paintwork example

achieve that the electrical properties do not have 45 to 27 parts by weight of an unsaturated polyester

deteriorated and the molded parts especially from moisture an acid number of 32, made from 35 mole percent

Activity absorption protects fumaric acid, 15 mol percent isophthalic acid and

50 mole percent ethylene glycol in the melt

with 3 parts by weight of diallyl phthalate, 1 part by weight

Example I _go tert-butyl perbenzoate, 2 parts by weight of zinc stearate,

22 parts by weight of an unsaturated polyester with 2 parts by weight of red ground phosphorus, 45 parts by weight of 37 acid number, made from 30 mole percent by weight of ground talc, 5 parts by weight of ge-fumaric acid, 20 mole percent of terephthalic acid and ground limestone and 15 parts by weight of cut-50 mole percent of 1,4-butanediol In the melt, tener glass fiber, cutting length 3 mm, equipped with 2 parts by weight of diallyl phthalate, 1 part by weight of a vinylsilane size, are dry mixed and butyl peroctoate, 1.5 parts by weight of zinc stearate, and finally 1 part by weight of plastic in a heated Buss extruder are anterted red, ground phosphorus, 62.5 parts by weight of ground talc and 10 parts by weight of ground talc and 10 parts by weight after solidification , dry for 60 minutes at 160 ° C and 1 50 kp / cm ² pressure, laser-mixed and then plasticized on heated rollers, test specimens can be produced from them, which are then fied and processed into thin skins. After having excellent properties: The skins can be solidified into a fine-grained one

Grind press powder that is arc-proof in the compression molding process according to ASTM 495

in 3 minutes at 16O ⁰ C and under a pressure 65> 240 seconds

of 150 kg / cm ^{2 processed} to test rods and plates - arc resistance according to the in Example 1

The molded parts obtained in this way have the following fast method at 40 kV and 100 mA.

Properties to well over 5 minutes,

Tracking resistance according to DIN 53480,
Procedure with test solution A- level KB> 600,
Resistance to embers according to DlN 53459 grade 4 (weight loss 120 mg, flame path 0.4 cm)

Comparative experiment

Instead of the talc proposed according to the invention, the inorganic filler used is exclusively 50 parts by weight used ground limestone

One manufactured in the same way as in Example 2 and processed plate had the following characteristics

Arc resistance according to ASTM D 495 181 seconds,

Arc resistance according to that explained in Example 1 Procedure at 40 kV and 100 mA. 3 seconds,

Tracking resistance according to DIN 53480,
Procedure with test solution A * level KB 420,
Resistance to embers according to DIN 53459. Grade 4 (weight loss 130 mg, flame distance 0.5 cm).

These values show the major disadvantages compared to Molded parts made from the compositions according to the invention

409518/442

Claims (4)

1 2 is built, which cause a short circuit Patent claims was <■ The effects that occur when the plastic surface 1 Hardable molding compounds made from (A) unsaturated flat are triggered by an electric arc Polyesters made from tere- and / or isophthalic acid, 5 extremely difficult to identify Fumaric acid and, optionally, maleic acid, depolymerization and cracking occur and diols on the other hand, (B) copolymerization coking and graphitization, presumably unsaturated monomers, (C) hardening catalysts that increase the conductivity particularly quickly, (D) fine red phosphorus, named phenomena often lead to splitting off easily- (E) other inorganic fillers and (F) io volatile compounds that may be omitted other common additives, ignites and the fire of the entire part where the molding compound introduces at least 10 weight. On the other hand, the correlates with certainty percent consists of components (A) + (B), resistance to leakage current with the arc resistance marked that the speed is a prerequisite for arc resistance inorganic filler talc or a combination 15 is therefore a high tracking resistance and a good one tion of talc and alkaline earth carbonate as essential flame retardancy Contains borrowed component The known experiments were therefore less concerned 2 molding compositions according to claim 1, characterized in that the chemical degradation is reduced indicates that the red phosphorus in the action of an electric arc than with the possibility of Amount of from 0.2 to 10, preferably from 0.5 to 20, which has arisen or arises once, mainly from 5 percent by weight, based on the entire graphite existing conductive layers by secondary mass, contains is to break down reactions So it is described that additives 3 molding compositions according to claim 1 or 2, characterized by hydrates, for example aluminum oxide hydrate, characterized in that talc and alkaline earth carbonate can eliminate graphitization formed, inin a weight ratio of 5 1 to 20 · 1 25 that which is released when the hydrate is heated water and carbon are present according to the equation 4 Use of the masses according to one of the C + HO = CO + H
Claims 1 to 3 for the manufacture of electrotechnical ^{2 2} nischer components with increased arc resistance and converted into gaseous products 30 Since this reaction is by no means quantitative, the resulting conductive graphite layer is also not quantitatively degraded, so the effect is not The invention relates to one eliminated under pressure and heat, but at most braked at the same time is a hardenable molding compound based on unsaturated polyester, therefore the addition of inorganic hydrate is problematic, polymerisable monomers, red phosphorus, because the water released under heat breaks up the synthetic organic fillers, hardening catalysts and composite materials and partially destroys them usual components as well as molded parts from it leads to the molded part tion Molding compositions based on unsaturated polyester with the disadvantage that the known fillers a The structure described above will usually only cause decreased arc resistance in the hardened state, excellent electrical properties are thereby remedied according to the invention and even over- properties and are therefore often compensated for as iso- lation parts used For molding compounds on the basis of the formula _Mff unu \ ς succeeds in achieving specific resin compositions. ο 1 Further, the tracking resistance of manufactured therefrom ^{Sa ll} ^ ^{2 4 loj} raised molded parts and 45 has to be used as the sole filler or in combination with this class of substances is used for the manufacture of parts to fillers containing carbonate, ζ B calcium carbonate use that are particularly resistant to knechstrom or other alkaline earth carbonates A Knechstrom arises when the surface of the subject matter of the invention are now those in the anlsoher material become conductive due to pollution claim 1 specified hardenable molding compounds, which for Is however this conductive connection between under 50 production of molded parts with increased arc voltage Standing parts are not complete or strength is particularly suitable as anorgasia due to the effect of the leakage current, Unter- nisch filler is a combination of talc and broken, can - especially at higher voltages alkaline earth carbonate preferred The polyester and mo- ignite an arc. In addition, luminomers are present in it in an amount of at least 10, bent during switching operations by a light 55 preferably at least 15 percent by weight, the red one But plastics are bent as a rule as much phosphorus in an amount of 0.2 to 10, preferably thermally stressed that on their surface by 0.5 to 5 percent by weight, the talc in one Decomposition in the foreseeable future a conductive layer amount of 10 to 70, preferably 20 to 60 Ge, which leads to the short circuit contain weight percent, with the percentages There has therefore been no shortage of attempts; molded parts 60 are always based on the total molding compound, talc to develop on the basis of unsaturated polyester, which and alkaline earth carbonate are preferred in one ge eme have increased arc resistance to a weight ratio of 5 1 to 20 1 present They are also used in heavy current engineering with high electricity - total amount of talc, red phosphorus and, if Applying tensions The technical advantage over alkaline earth carbonate is present, also on this, should above the state of the art there would be 65 no more than 85 and those of lime and red phosphorus if a permanent on the plastic surface is preferably not more than 70 percent by weight The term »fillers« includes reinforcing materials little thermal degradation that no conductive layer a