DE3625188A1 - Process for the antistatic finishing of polyamides/polyimides, materials which have been provided with an antistatic finish and their use - Google Patents

Abstract

The invention relates to a process for the antistatic finishing of materials based on polyamides (nylons), polyimides or polyamideimides, where the material mouldings are treated with a 0.1-30% strength by weight solution of salt mixtures of a) CaCl2, MgCl2, LiCl, NaCl and/or KCl, and b) AlCl3, FeCl3, TiCl4, SbCl5, CuCl2, FeCl2, CaCl2 and/or MoCl5, or chelate complexes thereof with Schiff bases, amines, carboxylic acids, diketones, alpha , beta -unsaturated ketones and phosphines, in an alcohol, preferably at temperatures of 15-40 DEG C, and the mouldings are dried after washing with water or solvents. The invention also relates to antistatic mouldings treated by the process, and to their use.

Description

The invention relates to a method for antistatic Finishing of materials based on polyamides, Polyimides or polyamideimides, where the molded material with a 0.1-30% by weight solution from salt mixtures

• a) CaCl₂, MgCl₂, LiCl, NaCl and / or KCl and
• b) AlCl₃, FeCl₃, TiCl₄, SbCl₅, CuCl₂, FeCl₂, CaCl₂ and / or MoCl₅
  or their chelate complexes with Schiff bases, amines, carboxylic acids, diketones, α , β- unsaturated ketones and phosphines,

in an alcohol, preferably at temperatures of Treated 15-40 ° C and the moldings after washing with Water or solvents can be dried.  

Claims are also made according to the procedure antistatic moldings and their use.

Organic, synthetic and natural polymers are generally electrical insulators. Your specific Resistance is between 10¹⁰ and 10¹⁸ Ω · cm.

Are special polymers with a polyconjugated structure the main chain with strong oxidizing or reducing agents treated, their specific resistance falls from approx. 10⁹ to approx. 10 Ω · cm (see for example "Organic Semiconductors, F. Gutmann and L.E. Lyons, John Wiley and Sons, Inc., New York (1967)). Such conjugated However, polymers are not used in plastics technology usual methods such as injection molding, extrusion, Calendering processable and not in common organic and inorganic solvents soluble.

Another way of anti-static equipment in polymers is the addition of charge transfer complexes, for example based on tetrathiofulvalene or tetracyanquinodimethane (cf. for example DE-B 31 31 251), the incorporation of these complexes in polymer matrices is very complex and therefore for the plastics processing industry - except in whole special cases - not interesting.

It is also possible to apply antistatic agents to the surface to apply a finished plastic part or directly into the polymer matrices during production to incorporate, e.g. B. ethoxylated fatty amines, long-chain Phosphoric acid ester and long chain paraffin salts. in the  first case is due to the low adhesion of the antistatic agent achieves a temporary antistatic effect, in the second case, their familiarization is impaired in many cases the original physical and chemical properties of the polymer material. In this Context should be mentioned that the said antistatic agents under very specific conditions, such as when there are enough high humidity have an antistatic effect.

Furthermore, DE-A 34 35 841 shows that salts of sulfonic acids as used in the sufonation of Alkenylalkyl polyglycol ethers of the formula

R₁, -O (C _n H _{2 n} O) R₂

with sulfur trioxide and subsequent hydrolysis, are suitable as antistatic agents for polyamides (PA). The above, modified by an SO₃ aftertreatment Antistatic agents have a useful effect on PA, but due to external influences such as low humidity or by light mechanical or chemical After a few weeks.

Furthermore, the literature z. B. DE-A 34 09 462 taken be based on thermoplastic mixtures of polymeric compounds and pyrrole polymers, the polymerized with oxidants containing oxygen are distinguished by their good electrical conductivity award.

In this case too, the physical properties of the matrix polymer such as impact and notched impact strength,  Tensile, elongation or elasticity behavior affected by the polypyrrole.

It should also be mentioned that films which permit pyrrole permeation or diffusion are pretreated with pyrrole on one side and then the pyrrole taken up is polymerized on the other side with the aid of aqueous FeCl 3 solution to give the doped polypyrrole. This technically very complex process is limited to some materials that are highly permeable to pyrrole, such as polypropylene nonwovens, etc., and leads to products with very high conductivity values of approx. 10-30 Ω ^-1 · cm ^-1 (see e.g. V. Bocchi and GP Gardini, J. Chem. Soc., Chem. Communications, p. 148 (1986)). As is known, however, such electrically highly conductive materials can be used in the antistatic field.

Furthermore, it can be seen from the literature that polymer films coated with pyrrole and then post-treated in an aqueous FeCl₃ bath have surface conductivity in the range from 10 ^-1 -10 ^-9 Ω ^-1 · cm ^-1 . Here, the coating of polyol is achieved either by vapor deposition or by immersion in a mixture consisting of a solvent and the pyrrole. The solvents used do not cause swelling or partial roughening of the substrate surface.

Unfortunately, the conditions so applied are not abrasion- or adherent. Also their antistatic effect leaves  by external influences, such as light mechanical or chemical stress very quickly.

The object of the invention is conventional polymers Materials such as foils, nonwovens, fabrics, fibers and Injection molded parts etc. based on conventional polyamides / polyimides through subsequent treatment with a permanently antistatic, abrasion-resistant or good adhesive medium without the mechanical and chemical properties of the polymer To negatively influence base material.

Surprisingly, this object is achieved by by using polymer materials based on conventional Polyamides and polyimides with a solution Mix of

• a) CaCl₂ and / or KCl and / or LiCl and / or NaCl and / or MgCl₂ With
• b) AlCl₃ and / or FeCl₃ and / or TiCl₄ and / or SbCl₅ and / or SnCl₂ and / or ZnCl₂ and / or MoCl₅ and / or CuCl₂

or the chelate complexes of b) treated with Schiff bases, amines, carboxylic acids, diketones, α , β- unsaturated ketones and phosphines, in a technical alcohol. The alcohols suitable for carrying out the process according to the invention are primary, secondary and tertiary alcohols with 1-8 C atoms, in particular primary and secondary alcohols with 1-4 C atoms, for example ethanol, methanol, isopropanol, isobutanol, n-butanol and n -Propanol, or lower glycols or glycol monomethyl ether.

The substrates are generally treated at -15 ° C to the boiling point of the solvents used, preferably at 15-40 ° C, particularly preferably at RT (Room temperature) d. H. 17-25 ° C.

Another method variant is that the substrate with a mixture consisting of a commercially available Antistatic and the halogen-containing, treated alcoholic solvent system. As antistatic agents come long chain C₈-C₃₅ paraffin sulfone salts, quaternary ammonium salts such as tetrabutylammonium chloride, Tetramethylammonium bromide, diethyldibutylammonium sulfate, Tricapryl-methylammonium chloride, tetracaprylmethylammonium bromide, water-soluble salts of sulfonic acids RSO₃Na, where R is a straight-chain alkyl radical with 8- 30 C atoms, preferably with C₈-C₁₂ atoms, also alkenylalkyl polyglycol ether in question. For alkyl glycol polyglycol ethers of the formula

R₁-O- (C _n H _{2 n} -O) _x -R₂

means

R₁H or a straight-chain alkenyl radical with 8-35 C atoms, R₂H or an alkyl radical with 1-12 C atoms and n is an integer from 2-4, while x can assume values from 0 to 35.

Polyethers with n = 2 and / or 3 and molecular weights of 150 to 5000 are preferred.

Furthermore, salts of such sulfonic acids are in their starting material R is an unsaturated fatty alkyl radical and as a cation alkali, alkaline earth, ethanolammonium, diethanolammonium and have triethanolammonium ions for Suitable implementation of the method. Furthermore, for Implementation of the general phosphine oxide process formula

as described for example in US-A 37 09 852, preferably decyl / hexyl / octyl phosphine oxides (such as described in EP-A 01 34 482) be set.

The total amount of antistatic agents is preferably 0.2- / 10 wt .-%, particularly preferably 0.5-5 wt .-%, whole particularly preferably 1.0-2.5% by weight.  

Of course, the organometallic Connections of the elements of Al, Fe, Ti, Sb, Mo and Cu be used to carry out the method. To in our observations, such complex compounds the above Elements based on diketones such as pentanedione-2,4, unsaturated ketones such as mesityl oxide, aromatic and or aliphatic Schiff bases, aliphatic and aromatic amines or carboxylic acids suitable. As another, to carry out the Complex ligands suitable for the process are aromatic or aliphatic phosphines such as triphenylphosphine or Tributylphosphine mentioned.

One goes into the practical implementation of the procedure Advantageously, before that the molded polyamide immersed in the antistatic finishing system according to the invention, after 0.5-30 minutes, preferably 1-15, completely particularly preferably 5-7.5 minutes, removed from the bath and freed of adhering solvent.

The solvent is generally removed by evaporation, if necessary under reduced pressure Print. Higher boiling solvents are expedient by extraction or rinsing with low-boiling Solvents removed.

The method according to the invention is applicable to all (in particular commercially available) aromatic and / or aliphatic Polyamide types, especially semi-crystalline Types such as polyamide-6, polyamide-6,6, polyamide-10, -11 and -12 and mixed types applicable.  

The process is also based on aromatic and aliphatic Polyamides or polyamide imides such as Kevlar® and Kapton® Types applicable. It can contain both filler and also unfilled polyamides, polyimides and polyamide imides treated with equal success. Filler admixtures shorten the required amount depending on the proportion Treatment time of the unfilled material.

In addition, extremely impact-resistant substrates, such as grafted with rubber, polyisoprene or polybutadiene or mixed polycondensates for implementation the process is ideally suited.

Example 1

A 90 × 100 × 3 (mm) thick glass fiber reinforced (30 wt .-%) plastic plate made of polyamide-6 is in an antistatic bath, which

1400 ml of methanol 125.0 15.0 gCaCl₂ gFeCl₃ 400 mlH₂O _least 2.0 gBenzyldodecyldimethylammoniumchlorid

contains, treated for 5 minutes at room temperature (RT), then washed with distilled water and 120 Dried for minutes at 80 ° C.

You get a permanently antistatic one Polymer plate with a surface resistance of 3 · 10⁸ Ω cm and a half-life of 2 seconds.

The surface _resistance R _OA was determined according to DIN 53 482 and the half-life according to DIN 53 486. The impact strength tests according to DIN 53 453 / ISO R 173 show that their impact strength is not influenced by the antistatic treatment process.

Example 2

An injection molded part made of rubber-modified polyamide-6 will turn into a solution

1500 ml methanol 125.0 g CaCl₂ 4.0 gTeCl₄

Treated for 10 minutes at RT and then washed with H₂O _dest , dried at 110 ° C for 3 h.

You get a permanently antistatic one Polymer plate with a surface resistance of 10⁸ Ω · cm, determined according to DIN 53 482 and a half-life of 1.5 seconds, determined according to DIN 53 486. The Impact or impact strength of the material is determined by does not affect the treatment process.

Example 3

A 90 × 150 × 3 (mm) injection molded plastic sheet a commercially available polyamide-6,6 becomes an antistatic bath out

1500 ml ethanol 110.0 g CaCl₂ 19.0 gFeCl₃

treated at RT for 3 minutes, 1 minute with distilled water and then 30 Dried minutes at 110 ° C. You get one permanently antistatic plate. The so antistatic one Shaped body was a modified temperature Exchange test according to DIN 53 496 suspended, the Heat storage at + 110 ° C and cold storage at -40 ° C took place. The "antistatic pad" is liable to the Molded body surface or on the molded body matrix so firmly that it shows no change. The impact or notched impact strength is not affected by the antistatic treatment influenced.

Example 4

A molded part made of a mineral fiber reinforced with 40 wt .-% Polyamide-6 is made in a solution

1000 ml n-butanol 100.0 gLiCl 19.0 gFeCl₃ 5.0 g benzyltriethylammonium chloride

Treated at 30 ° C for 8 minutes, rinsed according to Example 1 and then dried.

A molded article with a permanently antistatic finish is obtained, whose surface _resistance R _OA according to DIN 53 482 7 · 10⁷ Ω · cm or half-life according to DIN 53 486 is 0.9 seconds.

Example 5

A 90 × 150 × 3 mm thick plastic plate made of 30% rubber-offset polyamide-6 is in an antistatic bath, which

1000 ml isopropanol 100.0 g CaCl₂ 17.5 g FeCl₃ 200.0 ml H₂O _dest 8.0 g tetraethylene glycol dimethyl ether

contains, treated for 12.5 minutes at RT, then in distilled water rinsed and dried at 50 ° C overnight.

You get a permanently antistatic polymer plate with a surface resistance of 10⁷ Ω · cm or a half-life of ∼1.5 seconds.

Example 6

A 90 × 150 × 3 (mm) thick glass fiber reinforced (30 wt .-%) plastic plate made of polyamide-6 is in an antistatic bath, which  

1500 ml methanol 125.0 gCaCl₂ 17.0 gSnCl₂ 8.0 g octadecylamine 400 mlH₂O _dest

contains, treated for 8 minutes at 35 ° C, with distilled Washed water and then at 80 ° C overnight dried.

You get a permanently antistatic and wear-resistant Material. This material was modified Temperature change test exposed according to Example 3. The "antistatic pad" adheres to or on the Molded surface so firm that there is no change shows.

Example 7

A 100 × 100 × 0.5 (mm) thick clear plastic sheet polyamide-6 and polyamide-11 become one Bathroom consisting of

1000 ml n-butanol 80.0 g CaCl₂ 25.0 gAlCl₃ 14.0 g octadecylsulfonic acid sodium salt

Treated at RT for 19 minutes and then according to example 1 dried.  

You get a transparent, permanently antistatic equipped polymer film with a surface resistance of 10 Ω · cm determined according to DIN 53 482 or one Half-life of ∼1.3 seconds determined according to DIN 53 486.

Example 8

A 100 × 100 × 0.5 mm Kapton® film from Dupont / Wilmington, U.S.A., consists of a bath out

1000 ml ethanol 175.0 g CaCl₂ 50.0 gZnCl₂

Treated at 37.5 ° C for 40 minutes and then dried according to Example 2.

You get a permanently antistatic or transparent Polymer plate.

Example 9

A 100 × 100 × 0.8 mm thick, glass mat reinforced, co-extruded plastic sheet made of polyamide-6 and Polyamide 11 is made up of in a bath  

1500 ml methanol 140.0 g CaCl₂ 25.0 gFeCl₃ 150 mlH₂O

Treated, washed and washed at 30 ° C for 9 minutes then dried according to Example 1.

You get a permanently antistatic one Plastic plate with a surface resistance of 10⁸ Ω · cm and a half-life of 2 seconds. The "antistatic equipment" adheres to the surface of the molded article or on the molded matrix so firmly that despite Storage in distilled water for several days at RT shows no change. From further investigations shows that the physical properties like Tensile strain or modulus of elasticity of the polymer material through the Antistatic treatment cannot be affected.  

Example 10

A 100 × 100 × 0.9 mm thick, wollastonite reinforced Polyamide 6 plate is made up of in a bath

100 ml ethylene glycol 100 ml H2O 150.0 g CaCl₂ 29.0 g Fe ^III acetylacetonate 3.0 g tetraethylene glycol dimethyl ether

Treated at 65 ° C for 10 minutes, with H₂O dest. washed and then dried according to Example 1.

You get a permanently antistatic one Plastic plate with a surface resistance of 10⁸ Ω · cm and a half-life of 1.5 seconds. The "antistatic equipment" adheres to the surface of the molded article so firm that they passed the adhesion test according to DIN 53 151 with Gt · O consists.

Example 11

A 100 × 100 × 0.8 mm thick polyamide sheet after Example 9 is made up of in a bath

1000 ml methanol 125.0 g CaCl₂ 100.0 ml H₂O 38.0 g of Fe III complex of the Schiff base Basis of benzaldehyde and aniline (see manufacture for example, P. S. Zacharias et al., Indian J. Chemistry, 24A, 936 (1985))

will  Treated at RT for 12 minutes, washed and then dried according to Example 1.

You get a permanently antistatic one Plastic plate with a surface resistance of 10⁸ Ω · cm and a half-life of 2 seconds.

Example 12

A polyamide sheet according to Example 5 is in one Antistatic medium, which

1000 ml ethanol 100.0 gKCl 20.0 g FeIII complex of the Schiff base Basis of aniline and salicylaldehyde (see manufacture for example, P. S. Zacharias et al, Indian J. Chemistry, 24A, 936 (1985))

contains, treated at RT for 12.5 minutes, washed and then dried according to Example 1.

You get a permanently antistatic one Plastic plate with a surface resistance of 10⁷ Ωcm. The half-life of the discharge is ∼1.5 Seconds.  

Example 13

A molded part according to Example 4 is in a solution consisting of

1000 ml of n-propanol 100.0 g CaCl₂ 30.0 g of tetrabutyl titanate 2.0 g tetrabutylammonium bromide

Treated for 15 minutes at RT, washed with H₂O and then dried according to Example 1. You get a permanently antistatic plastic plate with a surface resistance of 10⁸ Ω · cm and a half-life of ∼2 seconds. The "antistatic equipment" adheres to the surface of the molded part so firmly that it passes the adhesion test according to DIN 53 151 with Gt0-Gt1.

Example 14

A polyamide sheet according to Example 6 is placed in an antistatic bath, consisting of

1000 ml n-butanol 100.0 mlH₂O dest. 19.0 g5-methyl-5-hexen-2,4-dione FeCl₃ complex (See production, for example, M. T. Teyssie et al. J. Polym. Sci. 50, 154- and 253 (1961)

Treated for 8 minutes at RT, with H₂O dest. washed and then at 90 ° C in a drying cabinet for 60 minutes dried long. You get a permanent antistatic equipped plastic plate with a surface resistance of 10⁷ Ω · cm and a half-life of 1.5 Seconds. The "antistatic equipment" adheres to the surface of the molded article so firm that they pass the adhesion test according to DIN 53 151 with Gt1.

Example 15

A polymer plate according to Example 8 is in a medium consisting of

1000 ml ethanol 55.0 g CaCl₂ 8.0 g CuCl₂-1,4,8,12-tetraazacyclopentadecane (s. Manufactured for example D.H. Bush, Inorganic Syntheses, XX, 108 John Wiley and Sons New York (1980)

treated and then cleaned according to Example 14 or dried. You get a permanent anti-static Plastic plate with a surface resistance of 10⁹ Ω · cm and a half-life of ∼3 seconds.

Claims (12)

1. A process for the antistatic finishing of materials based on polyamides or polyimides or polyamide-imides, characterized in that they are mixed with a solution of

• a) CaCl₂ and / or KCl and / or LiCl and / or NaCl and / or MgCl₂
• b) AlCl₃ and / or FeCl₃ and / or TiCl₄ and / or SbCl₅ and / or SnCl₂ and / or ZnCl₂ and / or FeCl₃ and / or CuCl₂ and / or MoCl₅, or their chelates with Schiff bases, amines, carboxylic acids, diketones, α , β - unsaturated ketones or phosphines,

treated in an alcohol. 2. The method according to claim 1, characterized in that that one uses a salt mixture of CaCl₂ and FeCl₃. 3. The method according to claim 1, characterized in that the treatment in a solution of CaCl₂, FeCl₃ in methanol or ethanol. 4. The method according to claim 1, characterized in that polyamides, polyimides or polyamide-imides with a solution of a mixture of

• a) CaCl₂ and / or KCl and / or LiCl and / or NaCl and / or MgCl₂
• b) Chelate complexes with Schiff bases, amines, carboxylic acids, diketones, α , β- unsaturated ketones and phosphines of the salts AlCl₃, FeCl₃, TiCl₄, SbCl₅, CuCl₂, FeCl₂, CaCl₂ and / or MoCl₅

treated in an alcohol. 5. The method according to claim 4, characterized in that one uses pentadione-2,4-complexes of the salts b). 6. The method according to claims 1 to 5, characterized in that the solutions quaternary ammonium salts in amounts of 0.1-5.0% by weight as an additional Antistatic agents included. 7. The method according to claims 1 to 5, characterized in that the solutions are organic sulfonic acid salts in amounts of 0.1-5.0% by weight as an additional Antistatic agents included. 8. The method according to claims 1 to 5, characterized in that said media oligo or poly (C₂- to C₄-oxyalkylene) ether with molecular weights from 150 to 6000 in quantities of 0.1-5.0% by weight included as additional antistatic agents.   9. Antistatic moldings made of materials based on polyamides or polyimides or polyamide / imides according to claims 1 to 8, characterized characterized that they are in the matrix or on the surface cations of the elements Al and / or Fe and / or Ti and / or Sb and / or Sn and / or Zn and / or Fe and / or Cu and / or Mo exhibit. 10. Use of antistatic materials according to claims 1-9 in household, electrical, Electronics, automotive, mining, plant and Refinery area.