DE3733570A1 - Thermoplastic moulding compositions comprising an aromatic polyester, a graft polymer and a fluorinated polyolefin - Google Patents

Abstract

Compositions based on a fully aromatic polyester, a graft polymer and a fluorinated polyolefin can be converted into mouldings having excellent properties.

Description

The invention relates to thermoplastic molding compositions Basis of fully aromatic polyester, graft polymer with a glass transition temperature below -10 ° C and fluorinated Polyolefin, a process for making this Molding compounds by mixing the components at elevated Temperature and the use of the molding compositions for production of moldings, primarily by injection molding.

"Fully aromatic polyester" in the sense of the invention also include fully aromatic polyester carbonates.

Fully aromatic polyester based on aromatic Dicarboxylic acids, diphenols and possibly carbonic acid have excellent mechanical properties and can withstand high thermal loads.

Fully aromatic polyesters are already available with graft polymers mixed; the resulting masses should improved impact strength, high heat resistance Have hydrolysis stability and good surface gloss (DE-OS 22 14 199, EP-A 30 414 and 1 31 188, US-PS 43 27 012).

From JP-A 56 005 848 it was known that 1 to 100 Parts by weight of a fluorinated resin, such as. B. Polytetrafluoroethylene (hereinafter: PTFE), based on 100 Parts by weight of fully aromatic polyester carbonate, the Processability and increased abrasion resistance.

In addition, JP-A 60 035 048 molding compounds from 20 to 80% by weight of fully aromatic polyester carbonate, 10 to 70% by weight of fibrous reinforcing agent or inorganic filler and 0.5 to 20% by weight fluorinated resin such as B. PTFE known. These molding compounds supposed to be excellent mechanical Properties, high heat resistance, low Have shrinkage and good release properties.

Indications of improved properties of polyester / Graft polymer mixtures can be mentioned Do not remove registrations.

Surprisingly, it has now been found that minor Amounts of fluorinated polyolefin have the properties of Mixtures of fully aromatic polyester and chews Further improve the Schukelastic graft polymer.  

The invention relates to thermoplastic molding compositions based on

• A. fully aromatic polyester,
• B. 0.1 to 30, preferably 0.1 to 12, in particular 0.1 to 3% by weight, based on component A, Graft polymer with a glass transition temperature below -10 ° C and
• C. 0.02 to 5, preferably 0.05 to 1, in particular 0.1 to 0.5% by weight, based on component A, fluorinated polyolefin.

A particularly preferred embodiment relates Molding compositions containing a mixture of components B and C made by mixing aqueous dispersion of this two components and through common coagulation has been obtained.

Fully aromatic polyester A in the sense of the invention aromatic polyesters and aromatic polyester carbonates, the predominantly to exclusively from aromatic C₈-C₁₄ dicarboxylic acids, C₆-C₃₀ diphenols and optionally carbonic acid derivatives, e.g. B. phosgene, are set up.

Examples of preferred aromatic dicarboxylic acids are: Isophthalic acid, terephthalic acid, diphenyl ether 4,4'-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid.  

Isophthalic acid and terephthalic acid are particularly preferred. The preferred carbonic acid derivative is phosgene.

Preferred diphenols for the production of fully aromatic Polyester A are compounds of the formula:

HO - Z - OH (I)

where Z is a divalent mono- or multinuclear aromatic radical with 6-30 C atoms means, where Z is built such that the two OH groups directly bound to one carbon atom of an aromatic system are.

Particularly preferred diphenols are compounds of Formula II

in the
Y is a single bond, an alkylene or alkylidene radical with 1-7 C atoms, a cycloalkylene or cycloalkylidene radical with 5-12 C atoms,

means  as well as their nuclear alkylated and nuclear halogenated Derivatives, e.g. B.

Hydroquinone,
Resorcinol,
Dihydroxydiphenyls,
Bis (hydroxyphenyl) alkanes,
Bis (hydroxyphenyl) cycloalkanes,
Bis (hydroxyphenyl) ether,
Bis (hydroxyphenyl) ketones,
Bis (hydroxyphenyl) sulfoxides,
Bis (hydroxyphenyl) sulfones and
a , α ′ -Bis- (hydroxyphenyl) -diisopropylbenzenes,
as well as their nuclear alkylated and nuclear halogenated derivatives.

The most important diphenols are: bisphenol A, tetra methylbisphenol A, 1,1-bis (4-hydroxyphenyl) isobutane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4'-dihydroxy diphenyl sulfide, 4,4'-dihydroxydiphenyl sulfone, and their di- and tetrahalogenated derivatives. Especially bisphenol A is preferred. Any can also be used Mixtures of the diphenols mentioned are used.

Possible branching agents are in DE-OS 29 40 024 and called 30 07 934.

As a chain terminator for the fully aromatic polyester A are preferably phenol, alkylphenols with C₁-C₁₂-  Alkyl groups, halogenated phenols, hydroxydiphenyl, Naphthols, chlorocarbonic acid esters from such phenolic Compounds and chlorides of aromatic Monocarboxylic acids, which are optionally substituted by C₁-C₂₂- Alkyl groups and halogen atoms can be substituted, in amounts of 0.1 to 10 mol% (in the case of phenols based on diphenols, in the case of acid chlorides based on acid dichlorides) used. Keep coming the chlorides of aliphatic monocarboxylic acids with up for 22 carbon atoms.

The structure of the fully aromatic polyester A can also up to 30, preferably up to 15, mol% of the dicarboxylic acids and dihydroxy compounds aliphatic assemblies, e.g. B. adipic acid, 1,4-butanediol, involved be.

Furthermore, the fully aromatic polyesters A partly from aromatic hydroxycarboxylic acids, e.g. B. p-Hydroxybenzoic acid. The proportion of such Hydroxycarboxylic acids can contain up to 100 mol% (based on Bisphenol).

If iso- and terephthalic acid together on the structure of fully aromatic polyester A may be involved whose ratio is 1:20 to 20: 1.

The fully aromatic polyester carbonates A can preferably up to 99 mol%, in particular up to 80 mol% particularly preferably up to 50 mol%, carbonate groups, based on the sum of ester and carbonate groups, contain.  

Both the ester and carbonate content of the full aromatic polyester carbonates A can be in the form of Blocks or randomly distributed in polycondensate A are available.

A desired carbonate group content can also by Mixing fully aromatic polyester with aromatic Polycarbonate can be adjusted.

The production of the fully aromatic polyester A is known and z. B. in DE-OS 14 95 626, 22 32 877, 27 03 376, 30 00 610, 27 14 544, 30 07 934. The phase interface method is particularly preferred.

The relative solution viscosity ( η rel) of the fully aromatic polyester A is in the range 1.18 to 1.4, preferably 1.22 to 1.3 (measured on solutions of 0.5 g polyester A in 100 ml CH₂Cl₂ solution at 25 ° C).

The graft polymers B comprise graft copolymers with rubber elastic properties that are essentially available from at least 2 of the following monomers are: chloroprene, 1,3-butadiene, isoprene, styrene, Acrylonitrile, ethylene, propylene, vinyl acetate and (meth) - Acrylic acid ester with 1 to 18 carbon atoms in the alcohol component; thus polymers such as z. B. in "Methods of Organic Chemistry "(Houben-Weyl), Vol. 14/1, Georg Thieme Verlag, Stuttgart 1961, pp. 393-406 and in C.B. Bucknall, "Toughened Plastics," Appl. Science Publishers,  London 1977. Preferred polymers B are at least partially cross-linked and possess Gel contents of over 20, preferably over 40% by weight, in particular over 60% by weight.

Preferred graft polymers B include graft polymers out

• B.1 5 to 90, preferably 30 to 80 parts by weight of a mixture
  • B1.1 50 to 95 parts by weight of styrene, α -methylstyrene, halogen- or methyl-substituted styrenes, methyl methacrylate or mixtures of these compounds and
  • B.1.2 5 to 50 parts by weight of acrylonitrile, methacrylonitrile, methyl methacrylate, maleic anhydride, C₁-C₄-alkyl or phenyl-N-substituted maleimides or mixtures of these compounds
• B.2 10 to 95, preferably 20 to 70 parts by weight Polymer with a glass transition temperature below -10 ° C.

Preferred graft polymers B are z. B. with styrene and / or acrylonitrile and / or (meth) acrylic acid alkyl esters grafted polybutadienes, butadiene / styrene copolymers and acrylate rubbers; d. H. Copolymers in DE-OS 16 94 173 (= US-PS 35 64 077) described type; with acrylic or methacrylic acid alkyl esters, vinyl acetate, acrylonitrile, styrene and / or  Alkylstyrenes grafted polybutadienes, butadiene / styrene or butadiene / acrylonitrile copolymers, polyisobutenes or polyisoprene, such as z. B. in DE-OS 23 48 377 (= US-PS 39 19 353) are described.

Particularly preferred polymers B are z. B. ABS Polymers such as z. B. in DE-OS 20 35 390 (= US-PS 36 44 574) or in DE-OS 22 48 242 (= GB-PS 14 09 275) are described.

Particularly preferred graft polymers B are graft polymers obtained by grafting from

• I. 10 to 70, preferably 15 to 50, in particular 20 up to 40% by weight, based on the graft product, at least a (meth) acrylic acid ester or one Mixture of 10 to 50, preferably 20 to 35% by weight, based on Gemsisch, acrylonitrile or (Meth) acrylic acid esters and 50 to 90, preferably 65 to 80% by weight, based on the mixture, of styrene
• II. 30 to 90, preferably 50 to 85, in particular 60 up to 80% by weight, based on the graft product Butadiene polymers with at least 50% by weight, based on II, butadiene residues as a graft base is available

wherein preferably the gel fraction of the graft base II is at least 70% by weight (measured in toluene), the degree of graft G 0.15 to 0.55 and the average particle diameter d ₅₀ of the graft polymer B 0.1 to 2, preferably 0.2 to 0 , 6 µm.

(Meth) acrylic acid esters I are esters of acrylic acid or Methacrylic acid and monohydric alcohols with 1 to 8 carbon atoms. Methyl methacrylates are particularly preferred, ethyl ester and propyl ester.

The graft base II can next to butadiene residues up to 50 wt .-%, based on II, residues of other ethylenically unsaturated monomers, such as. B. styrene, acrylonitrile, Esters of acrylic or methacrylic acid with 1-4 carbon atoms in the alcohol component (such as methyl acrylate, ethyl acrylate, Methyl methacrylate, ethyl methacrylate), vinyl esters and Contain vinyl ether. The preferred graft base II consists of pure polybutadiene.

As is known in the graft reaction, the graft monomers I not necessarily entirely on the graft base II are grafted according to the invention under Graft polymers B also understood such products by the polymerization of the monomers I in the presence of the basics II.

The degree of grafting G denotes the weight ratio of grafted graft monomers to the graft base and is dimensionless.

The mean particle size d ₅₀ is the diameter above and below which 50% by weight of the particles lie. It can be determined by means of ultracentrifuge measurements (W. Scholtan, H. Lange, Kolloid. Z. and Z. Polymer 250 (1972), 782-796).

Particularly preferred graft polymers B are z. Belly Graft polymers

• a) 20 to 90 wt .-%, based on B, acrylate rubber with a glass transition temperature below -20 ° C as Graft base and
• b) 10 to 80 wt .-%, based on B, at least one polymerizable ethylenically unsaturated monomers, his or her in the absence of (a) resulting homo- or copolymers a glass transition temperature above 25 ° C as a graft monomers.

The acrylic rubbers (a) of the polymers B are preferably polymers of acrylic acid alkyl esters, if appropriate with up to 40% by weight, based on (a), other polymerizable ethylenically unsaturated Monomer. Among the preferred polymerizable acrylic acid esters include C₁-C₈ alkyl esters, for example Methyl, ethyl, n-butyl, n-octyl and 2-ethylhexyl esters Halogen alkyl esters, preferably halogen-C₁-C₈- alkyl esters such as chloroethyl acrylate; as well as mixtures of these monomers.  

The acrylate rubbers (a) can be uncrosslinked or crosslinked, preferably partially cross-linked.

Monomers with more than one poly copolymerizable double bond. Preferred Examples of crosslinking monomers are esters unsaturated monocarboxylic acids with 3 to 8 carbon atoms and unsaturated monohydric alcohols with 3 to 12 carbon atoms or saturated polyols with 2 to 4 OH groups and 2 up to 20 carbon atoms, such as B. ethylene glycol dimethacrylate, Allyl methacrylate; polyunsaturated heterocyclic Connections such as B. trivinyl and triallyl cyanurate; polyfunctional vinyl compounds such as di- and tri vinyl benzenes; but also triallyl phosphate and diallyl phthalate.

Preferred crosslinking monomers are allyl methacrylate, Ethylene glycol dimethacrylate, diallyl phthalate and hetero cyclic compounds that are at least 3 ethylenic have unsaturated groups.

Particularly preferred crosslinking monomers are cyclic monomers triallyl cyanurate, triallyliso cyanurate, trivinyl cyanurate, triacryloylhexahydro-s- triazine, triallylbenzenes.

The amount of crosslinking monomers is preferably 0.02 to 5, in particular 0.05 to 2% by weight, based on the graft base (a).  

In the case of cyclic crosslinking monomers with at least 3 ethylenically unsaturated groups it is advantageous the amount to less than 1% by weight of the graft base (a) restrict.

Preferred "other" polymerizable ethylenically unsaturated monomers which, in addition to the acrylic acid esters, can optionally be used to prepare the graft base (a) are, for. B. acrylonitrile, styrene, α -methyl styrene, acrylamides, vinyl C₁-C₆ alkyl ether, methyl methacrylate, butadiene. Preferred acrylate rubbers as the graft base (a) are emulsion polymers which have a gel content of at least 60% by weight.

The gel content of the graft base (a) is in at 25 ° C Dimethylformamide determined (M. Hoffmann, H. Krömer, R. Kuhn, Polymer Analytics I and II, Georg Thieme Verlag, Stuttgart 1977).

The common for the preferred embodiment Precipitation to be used with the fluorinated polyolefin C. possess aqueous dispersions of graft polymer B. generally solids contents of 25 to 60, preferably from 30 to 45% by weight.

The fluorinated polyolefins C are high molecular weight and have glass transition temperatures of above -30 ° C., generally above 100 ° C., fluorine contents from 59 to 76, preferably from 65 to 76, in particular from 70 to 76% by weight and average particle diameter d ₅₀ from 0.05 to 20, preferably 0.08 to 10 µm. Preferred fluorinated polyolefins C are polytetrafluoroethylene, polyvinylidene fluoride, tetrafluoroethylene / hexafluoropropylene and ethylene / tetrafluoroethylene copolymers. The fluorinated polyolefins are known (cf. "Vinyl and Related Polymers" from Schildknecht, John Wilex & Sons, Inc., New York, 1962, pages 484-494; "Fluoropolymers" from Wall, Wiley-Intersience, John Wiley & Sons, Inc., New York, Vol. 13, 1970, pages 623-654; "Modern Plastics Encyclopedia", 1970-1971, Vol. 47, No. 10 A, October 1970, Mc Graw-Hill, Inc., New York, page 134 and 774; "Modern Plastics Encyclopedia", 1975-1976, October 1975, Vol. 52, No. 10 A, Mc Graw-Hill, Inc., New York, pp. 27, 28 and 472, and U.S. Patent No. 36 71 487, 37 23 373 and 38 38 092).

Have particularly preferred fluorinated polyolefins C. Densities in the range of 1.2 to 1.9 g / cm³ and show Melting points of <300 ° C. The fluorinated polyolefins C are preferably in non-sintered form used.

Preferred dispersions of fluorinated polyolefin C have solids contents of 30 to 70, in particular from 50 to 60% by weight. The mixtures of dispersions of the graft polymer B and the fluorinated polyolefin C can be worked up as usual, e.g. B. by Spray drying or freeze drying preferably at Temperatures of 20-150 ° C, especially 50-100 ° C.  

Drying can take place at 50-200 ° C, preferably between 70 ° C and 100 ° C.

The weight ratio of graft polymer B and the fluorinated polyolefin C in the co-precipitated product can preferably be 95: 5 to 60:40.

The molding compositions according to the invention can contain conventional additives, such as lubricants and mold release agents, nucleating agents, Antistatic agents, stabilizers, fillers and reinforcing materials, Flame retardants as well as dyes and pigments contain.

The filled or reinforced molding compounds can be up to 60, preferably 10 to 60 wt .-%, based on the filled or reinforced molding compound, filling and / or Reinforcing fabrics included. Preferred reinforcing materials are glass fibers. Preferred fillers that are also reinforcing glass balls, mica, silicates, Quartz, talc, titanium dioxide, wollastonite.

The molding compositions according to the invention can be mixed the components at elevated temperature, preferably in the range of 250 to 350 ° C, so e.g. B. in conventional devices, such as internal kneaders, Extruders or twin shaft screws, melt compounded or melt extruded. The components can into the mixing unit at the same time or in succession be introduced.  

Another object of the invention is a method to produce the molding compositions according to the invention Mix the components at elevated temperature.

The molding compositions according to the invention can be used for production of moldings of any kind, e.g. B. by injection molding will. Examples of molded articles are: housing parts for electronic computers and electrical devices, Cover plates for the construction industry, automotive parts.

Moldings can also be made by deep drawing from beforehand produced plates or foils.

Another object of the invention is therefore Use of the molding compositions for the production of moldings.

Claims (9)

1. Thermoplastic molding compositions based on

• A. fully aromatic polyester,
• B. 0.1 to 30 wt .-%, based on component A, graft polymer with a glass transition temperature below -10 ° C and
• C. 0.02 to 5% by weight based on component A, fluorinated polyolefin.

2. Molding compositions according to claim 1, wherein the component B in amounts of 0.1 to 15 wt .-%, based on Component A is included. 3. Molding compositions according to claim 1, wherein the component B in amounts of 0.1 to 3% by weight, based on the component A, is included. 4. Molding compositions according to claims 1-3, wherein component C in amounts of 0.05 to 1% by weight on component A, is included. 5. Molding compositions according to claims 1-3, wherein the Component C in amounts of 0.1 to 0.5 wt .-%, based on component A, is included.   6. Molding compositions according to claims 1-5, wherein component C consists of polytetrafluoroethylene. 7. Molding compositions according to claims 1-6, wherein component C is contained as a mixture with component B, by mixing aqueous dispersions of both components and subsequent joint precipitation has been obtained. 8. Process for the preparation of the molding compositions Claims 1-7 by mixing the components elevated temperature. 9. Use of the molding compositions according to claims 1-7 for Manufacture of molded articles.